enalapril has been researched along with Inflammation* in 26 studies
7 trial(s) available for enalapril and Inflammation
Article | Year |
---|---|
Inhibition of the renin-angiotensin system does not reduce platelet activity at rest or during stress in hypertension.
We investigated the influence of angiotensin receptor blockade and angiotensin-converting enzyme inhibition on stress-induced platelet activation in hypertensive patients. Secondary aims were effects on inflammation, coagulation, and endothelial function.. Following a 4-week placebo period, 25 hypertensive patients entered a double-blind, crossover study comparing enalapril (20 mg once daily) and losartan (100 mg once daily) treatment (each for 8 weeks). Patients were studied at rest and after a standardized exercise test.. Mean arterial pressure was reduced from 119 ± 2 to 104 ± 2 (enalapril) and 106 ± 2 (losartan) mmHg (both P <0.001). Plasma angiotensin II decreased from 2.4 ± 0.4 to 0.5 ± 0.1 pmol/l with enalapril, and increased to 7.2 ± 1.3 pmol/l with losartan (both P <0.001). Exercise-evoked platelet activation, as evidenced by increased numbers of P-selectin-positive platelets (P <0.01), elevated circulating platelet-platelet aggregates (P <0.01) and soluble P-selectin levels (P <0.001), and increased platelet responsiveness to adenosine diphosphate and thrombin (both P <0.05). Neither drug influenced these markers of platelet activation at rest or following exercise. Markers of inflammation (high-sensitivity C reactive protein, interleukin-6, tissue necrosis factor-α), coagulation (tissue plasminogen activator antigen, prothrombin fragment F1+2), and endothelial function (von Willebrand factor, soluble vascular cellular adhesion molecule-1, and intercellular adhesion molecule-1) were also uninfluenced by treatment.. Enalapril and losartan failed to reduce platelet activity both at rest and during exercise in hypertensive patients. Markers of inflammation, coagulation, and endothelial function were similarly unaffected. Inhibition of the renin-angiotensin system promotes its beneficial effects in hypertension through mechanisms other than platelet inhibition. Topics: Adult; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Blood Coagulation; Blood Platelets; Cross-Over Studies; Double-Blind Method; Enalapril; Endothelium, Vascular; Exercise Test; Female; Flow Cytometry; Humans; Hypertension; Inflammation; Losartan; Male; Middle Aged; Placebos; Renin-Angiotensin System; Treatment Outcome | 2013 |
Changes in urinary albumin excretion, inflammatory and oxidative stress markers in ADPKD patients with hypertension.
Autosomal dominant polycystic kidney disease (ADPKD) progresses more quickly to end-stage renal disease in patients with hypertension than in their normotensive counterparts. The authors investigated the effect of telmisartan versus enalapril on systolic and diastolic blood pressure (SBP and DBP), urinary albumin excretion (UAE), serum high mobility group box-1 protein (HMGB1), serum interleukin (IL)-6 and urinary 8-hydroxydeoxyguanosine (8-OHdG) levels in patients with hypertensive ADPKD.. Twenty patients with hypertensive ADPKD with good renal function were randomly assigned to 1 of 2 treatments: telmisartan 80 mg once daily (n = 10) or enalapril 10 mg once daily (n = 10). Treatment lasted 12 months. SBP, DBP, serum creatinine, UAE, HMGB1, IL-6 and urinary 8-OHdG levels were measured before and 6 and 12 months after treatment.. Both SBP and DBP were significantly reduced after treatment (P < 0.001) in both groups. Serum creatinine changed little during the experimental period in either group. UAE, serum HMGB1, serum IL-6 and urinary 8-OHdG levels were significantly decreased after treatment (UAE, HMGB1 and IL-6, P < 0.001; and 8-OHdG, P < 0.01 versus baseline levels) in both groups. However, the decreases in UAE, serum HMGB1 and serum IL-6 were significantly greater in the telmisartan group than in the enalapril group at 6 months (P < 0.05, P < 0.01 and P < 0.01, respectively) and 12 months (all, P < 0.05).. Telmisartan seems to be equivalent to enalapril in lowering BP, but telmisartan has more potent renoprotective, anti-inflammatory and antioxidative effects than enalapril in patients with hypertensive ADPKD. Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Albuminuria; Angiotensin-Converting Enzyme Inhibitors; Benzimidazoles; Benzoates; Biomarkers; Creatinine; Deoxyguanosine; Enalapril; Female; HMGB1 Protein; Humans; Hypertension; Inflammation; Interleukin-6; Male; Middle Aged; Oxidative Stress; Polycystic Kidney, Autosomal Dominant; Telmisartan | 2012 |
Inflammatory activation during coronary artery surgery and its dose-dependent modulation by statin/ACE-inhibitor combination.
On-pump coronary artery bypass graft (CABG) surgery triggers an inflammatory response (IR) which may impair revascularization. The study aimed at (1) characterizing the temporal profile of the IR by assaying appropriate markers in both systemic and coronary blood, and (2) determining whether (and which doses of) cardiovascular drugs known to have antiinflammatory properties, namely statins and ACE-inhibitors (ACEI), inhibit the response.. Patients scheduled for CABG (n=22) were randomized to statin/ACEI combination treatment at standard doses (STD, ramipril 2.5/simvastatin 20 mg, or atorvastatin 10 mg), or at high doses (HiDo, ramipril 10 mg, or enalapril 20 mg/simvastatin 80 mg, or atorvastatin 40 mg). Plasma levels of interleukin 6, tumor necrosis factor alpha, E-selectin, von Willebrand factor (vWF), and sVCAM-1 were serially assayed (ELISA) before, during, and after CABG. Blood was drawn from an artery, a systemic vein, and the coronary sinus. Myocardial perfusion scans were obtained before and 2 months after surgery in 19 out of 22 subjects. In the STD group both IL-6 and TNF displayed striking increases which were similar at all sites and peaked 10 to 60 minutes after aortic declamping. Such increases were drastically attenuated in the HiDo group. Instead, only modest increases in venous E-selectin, vWF, and sVCAM-1 were observed. Scintigraphic ischemia scores were entirely normalized after versus before CABG in the HiDo but not in the STD treatment group.. On-pump CABG surgery is associated with an intense systemic inflammatory response, which can be almost completely prevented by early treatment with high (but not standard) doses of ACE-inhibitors and statins. Topics: Aged; Angiotensin-Converting Enzyme Inhibitors; Anti-Inflammatory Agents; Atorvastatin; Coronary Artery Bypass; Coronary Artery Disease; Coronary Circulation; Creatine Kinase; Dose-Response Relationship, Drug; E-Selectin; Enalapril; Female; Heptanoic Acids; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Inflammation; Inflammation Mediators; Interleukin-6; Leukocyte Count; Male; Middle Aged; Platelet Count; Pyrroles; Ramipril; Simvastatin; Stroke Volume; Time Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1; von Willebrand Factor | 2007 |
Effects of nifedipine GITS 20 mg or enalapril 20 mg on blood pressure and inflammatory markers in patients with mild-moderate hypertension.
Calcium antagonists, angiotensin-converting enzyme (ACE) inhibitors and other drug classes either alone or in combination have been recommended for the treatment of hypertension. Nifedipine gastrointestinal therapeutic system (GITS) 20 mg is a new low-dose formulation with an improved tolerability. The aim of the present study was to compare the effects of nifedipine GITS 20 mg and enalapril 20 mg on blood pressure and circulating adhesion molecules in hypertensive patients.. This randomized, double-blind, multicentre trial compared the blood pressure lowering effects of a 12-week treatment of nifedipine GITS 20 mg vs enalapril 20 mg in 264 patients with mild-to-moderate hypertension.. Nifedipine GITS 20 mg induced a reduction of clinic blood pressure, which was similar to that observed with enalapril 20 mg. Nifedipine GITS and enalapril lowered mean sitting diastolic blood pressure by 11.8 and 12.4 mmHg, respectively, while systolic blood pressure was reduced by 15.3 and 16.3 mmHg, respectively. Ambulatory blood pressure monitoring-derived blood pressure data showed similar results in both groups without any statistically significant differences between treatments. Both enalapril and nifedipine tended to reduce ICAM-1 and E-selectin, while only nifedipine reduced von Willebrand factor. Both treatments were well tolerated.. Our findings demonstrate a similar antihypertensive effectiveness of a low dose (20 mg) of nifedipine GITS in comparison with a standard dose of enalapril (20 mg). Given its clinical efficacy and good tolerability, low-dose nifedipine GITS may be considered a valuable treatment option for hypertensive patients. Topics: Adult; Aged; Angiotensin-Converting Enzyme Inhibitors; Blood Pressure; Blood Pressure Determination; Blood Pressure Monitoring, Ambulatory; E-Selectin; Enalapril; Female; Humans; Hypertension; Inflammation; Intercellular Adhesion Molecule-1; Male; Middle Aged; Nifedipine; Treatment Outcome; Vasodilator Agents; von Willebrand Factor | 2005 |
Exploring the effects of ACE inhibitor tissue penetration on vascular inflammation following acute myocardial infarction.
Questions remain as to the existence of a class effect amongst angiotensin converting enzyme (ACE) inhibitors, and some literature suggests that pharmacological effects and outcomes may be determined by an ACE inhibitor's propensity to penetrate and inhibit the ACE enzyme at the vascular tissue level. Because vascular inflammation contributes to adverse outcomes following acute myocardial infarction (AMI), and angiotensin II influences inflammation at the vascular level, we hypothesized that high-tissue penetrating ACE inhibitors would provide more favorable effects on C-reactive protein (CRP) after AMI compared to low-tissue penetrating ACE inhibitors.. In a randomized open-label trial, patients received the high-tissue penetrating quinapril (n = 15) or low-tissue penetrating enalapril (n = 15) following AMI. C-reactive protein was measured at baseline and periodically over 14 days following drug initiation. All baseline characteristics and blood pressure response to treatment between groups were equivalent. Prior to initiating study medication, CRP concentrations (mg/g) were similar between enalapril and quinapril (0.327 +/- 0.571 versus 0.273 +/- 0.380, respectively, p = 0.77). The percent magnitude of change in CRP concentrations favored quinapril at all time points, starting 12 h after treatment initiation. When characterizing CRP production during treatments, the time courses were significantly different and demonstrated lower CRP concentrations with quinapril (p = 0.0107).. Overall, this investigation into the importance of ACE inhibitor tissue penetration on a common marker of vascular inflammation, suggests a potential vascular anti-inflammatory benefit with a more highly tissue penetrating ACE inhibitor following AMI. Further investigation into the true pharmacological similarities and differences amongst this class of drugs is warranted. Topics: Adult; Angiotensin-Converting Enzyme Inhibitors; C-Reactive Protein; Chi-Square Distribution; Coronary Vessels; Enalapril; Female; Humans; Inflammation; Male; Middle Aged; Myocardial Infarction; Quinapril; Tetrahydroisoquinolines | 2004 |
Comparative effects of AT1-antagonism and angiotensin-converting enzyme inhibition on markers of inflammation and platelet aggregation in patients with coronary artery disease.
We evaluated whether renin-angiotensin system (RAS) blockade attenuates cardiovascular events.. Because inflammation and enhanced thrombogenesis are hallmarks of atherosclerosis, we assessed whether RAS inhibition elicits anti-inflammatory and anti-aggregatory effects.. Interleukin 6 (IL-6), high-sensitivity C-reactive protein (hsCRP), metalloprotease 9 (MMP-9), and interleukin 10 (IL-10) were determined in patients with coronary artery disease (CAD) and arterial hypertension six to eight weeks after coronary angioplasty (low-density lipoprotein serum levels <150 mg/dl). Patients were randomized double-blind to either 20 mg enalapril (ENAL, n = 27) or 300 mg irbesartan (IRB, n = 21) for 3 months. Blood samples were drawn at baseline and at three months. Thromboxane A2-induced platelet aggregation was determined turbidimetrically; urine bicyclo-prostaglandin E2 (PGE(2)) and inflammatory markers were measured by enzyme-linked immunosorbent assay technique.. Both treatment regimens enhanced serum IL-10 levels (IRB p < 0.001, ENAL p < 0.03) and reduced serum MMP-9 protein (IRB p < 0.001, ENAL p < 0.05) and MMP-9 activity (IRB p < 0.005, ENAL p < 0.05). Only IRB reduced serum IL-6 and hsCRP levels significantly compared with baseline (p < 0.01), whereas ENAL did not (hsCRP p < 0.02 IRB vs. ENAL, p < 0.01 IRB vs. ENAL). Platelet aggregation was only reduced by IRB (p < 0.001, ENAL p < 0.06, IRB vs. ENAL p < 0.001) while urine PGE(2) levels remained unchanged.. Angiotensin-converting enzyme (ACE) inhibition and angiotensin II type 1 receptor (AT1) blockade reduced serum MMP-9 protein/activity to a similar extent, and only AT1 blockade reduced hsCRP, IL-6, and platelet aggregation in patients with CAD. Thus, AT1-blockade appears to exert stronger systemic anti-inflammatory and anti-aggregatory effects compared with ACE inhibition. Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Biomarkers; Biphenyl Compounds; C-Reactive Protein; Coronary Artery Disease; Dinoprostone; Double-Blind Method; Enalapril; Female; Humans; Hypertension; Inflammation; Interleukin-10; Interleukin-6; Irbesartan; Male; Matrix Metalloproteinase 9; Middle Aged; Platelet Aggregation; Tetrazoles; Thromboxane A2 | 2004 |
Angiotensin receptor blockade decreases markers of vascular inflammation.
A protective role against atherosclerosis can be attributed to angiotensin converting enzyme inhibitors (ACE-I), since they have been shown to reduce mortality in patients at cardiovascular risk. Since plasma levels of adhesion molecules are considered surrogate markers of endothelial cell activation and atherogenesis, we compared the levels of adhesion molecules after treatment with the ACE-I enalapril or the direct angiotensin- receptor antagonist losartan or placebo. In a randomized, controlled trial, 21 hypercholesterolemic volunteers received 50 mg/d losartan or 20 mg/d enalapril or placebo for twelve weeks. Plasma levels of circulating intercellular adhesion molecule-1 (cICAM-1), vascular adhesion molecule-1 (cVCAM-1), and E-selectin (cE-SEL) were measured by ELISA. Surface expression of ICAM-1 on circulating leukocytes was determined by flow cytometry. Enalapril and losartan but not placebo induced a small but stable decrease of cICAM-1 and cVCAM-1, while cE-SEL and leukocyte expression of ICAM-1 remained unchanged. The lowering of plasma adhesion molecules may indicate an antiatherogenic effect of angiotensin II blockade in hypercholesterolemia. While such preventive effect will have to be proven in clinical trials, our results do not support a preference for either enalapril or losartan with regard to their possible vasoprotective role. Topics: Angiotensin Receptor Antagonists; Blood Pressure; Cholesterol; Double-Blind Method; E-Selectin; Enalapril; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Humans; Hypercholesterolemia; Inflammation; Intercellular Adhesion Molecule-1; Leukocytes; Losartan; Male; Middle Aged; Pilot Projects; Receptors, Angiotensin; Vascular Cell Adhesion Molecule-1; Vascular Diseases | 2004 |
19 other study(ies) available for enalapril and Inflammation
Article | Year |
---|---|
Effect of angiotensin II pathway inhibitors on post-surgical adhesion band formation: a potential repurposing of old drugs.
In this study we investigated the therapeutic potential of angiotensin II pathway inhibitors in attenuating post-surgical adhesion band formation in tendon injury.. We assigned 30 Wistar albino rats to 5 groups, including negative control, positive control, sham, Telmisartan- and Enalapril-treated groups (n=6). Telmisartan and Enalapril at a dose of 10 mg/kg were administered intraperitoneally for 21 days. Hematoxylin-Eosin, and Masson's trichrome staining were used to measure the inflammatory cell accumulation and collagen deposition in the Achilles tendon tissue sections. Oxidative stress markers were analyzed in tissue samples by spectrophotometric methods. Properties of Achilles tendon adhesions were compared based on Tang and Ishiyama scoring systems in the presence and absence of angiotensin II pathway inhibitors.. Telmisartan and Enalapril reduced severity, length, and density of surgical-induced tendon adhesion at site of injury (***p < 0.001). Our results showed that administration of angiotensin II pathway inhibitors decreased infiltration of inflammatory cells to the injured area (*p < 0.05) and suppressed inflammation by regulating oxidative stress markers including MDA (***p < 0.001), total thiol (***p < 0.001), CAT (***p < 0.001), and SOD (***p < 0.001), in post-operative Achilles tendon tissues. Significant lower collagen deposition and formation of fibrotic tissues was seen in Telmisartan- and Enalapril-treated groups as detected by Masson's trichrome staining which correlated with a decrease in quantity (**p < 0.01) and grading of fibrosis score (***p < 0.001), in adhesive tissues. Moreover, inhibition of angiotensin II pathway could also ameliorate mechanical properties including ultimate load (***p < 0.001), and ultimate stress (*p < 0.05) in injured Tendons.. Our results showed that ssuppression of inflammation and fibrosis are two mechanisms by which Telmisartan and Enalapril elicit potent protective responses post Achilles tendon injuries. Topics: Angiotensin II; Angiotensin-Converting Enzyme Inhibitors; Animals; Benzimidazoles; Drug Repositioning; Enalapril; Eosine Yellowish-(YS); Fibrosis; Hematoxylin; Inflammation; Pharmaceutical Preparations; Rats; Rats, Wistar; Sulfhydryl Compounds; Superoxide Dismutase; Telmisartan; Tissue Adhesions | 2022 |
Angiotensin-converting enzyme inhibitor treatment early after myocardial infarction attenuates acute cardiac and neuroinflammation without effect on chronic neuroinflammation.
Myocardial infarction (MI) triggers a local inflammatory response which orchestrates cardiac repair and contributes to concurrent neuroinflammation. Angiotensin-converting enzyme (ACE) inhibitor therapy not only attenuates cardiac remodeling by interfering with the neurohumoral system, but also influences acute leukocyte mobilization from hematopoietic reservoirs. Here, we seek to dissect the anti-inflammatory and anti-remodeling contributions of ACE inhibitors to the benefit of heart and brain outcomes after MI.. C57BL/6 mice underwent permanent coronary artery ligation (n = 41) or sham surgery (n = 9). Subgroups received ACE inhibitor enalapril (20 mg/kg, oral) either early (anti-inflammatory strategy; 10 days treatment beginning 3 days prior to surgery; n = 9) or delayed (anti-remodeling; continuous from 7 days post-MI; n = 16), or no therapy (n = 16). Cardiac and neuroinflammation were serially investigated using whole-body macrophage- and microglia-targeted translocator protein (TSPO) PET at 3 days, 7 days, and 8 weeks. In vivo PET signal was validated by autoradiography and histopathology.. Myocardial infarction evoked higher TSPO signal in the infarct region at 3 days and 7 days compared with sham (p < 0.001), with concurrent elevation in brain TSPO signal (+ 18%, p = 0.005). At 8 weeks after MI, remote myocardium TSPO signal was increased, consistent with mitochondrial stress, and corresponding to recurrent neuroinflammation. Early enalapril treatment lowered the acute TSPO signal in the heart and brain by 55% (p < 0.001) and 14% (p = 0.045), respectively. The acute infarct signal predicted late functional outcome (r = 0.418, p = 0.038). Delayed enalapril treatment reduced chronic myocardial TSPO signal, consistent with alleviated mitochondrial stress. Early enalapril therapy tended to lower TSPO signal in the failing myocardium at 8 weeks after MI (p = 0.090) without an effect on chronic neuroinflammation.. Whole-body TSPO PET identifies myocardial macrophage infiltration and neuroinflammation after MI, and altered cardiomyocyte mitochondrial density in chronic heart failure. Improved chronic cardiac outcome by enalapril treatment derives partially from acute anti-inflammatory activity with complementary benefits in later stages. Whereas early ACE inhibitor therapy lowers acute neuroinflammation, chronic alleviation is not achieved by early or delayed ACE inhibitor therapy, suggesting a more complex mechanism underlying recurrent neuroinflammation in ischemic heart failure. Topics: Acute Disease; Angiotensin-Converting Enzyme Inhibitors; Animals; Chronic Disease; Enalapril; Heart; Inflammation; Mice; Mice, Inbred C57BL; Myocardial Infarction; Nervous System Diseases | 2020 |
Enalapril inhibits inflammatory osteolysis induced by wear debris in a mouse model.
Aseptic loosening, the most frequent complication after total joint replacement, is probably caused by an inflammatory response to the shedding of wear debris from the implant. The only effective treatment is surgical revision. Using a mouse model, we investigated whether enalapril inhibits wear debris-induced inflammatory osteolysis.. Titanium (Ti) alloy particles were introduced, and calvarial bone from syngeneic mice was implanted into air pouches established in BALB/c mice. Histological and molecular analyses were performed with inflammatory tissue samples obtained from mice treated with and without enalapril.. Enalapril inhibited tissue inflammation and inflammatory osteolysis induced by Ti particles, reducing pouch membrane thickness and decreasing inflammatory cell infiltration. In addition, enalapril inhibited the expression of the inflammatory cytokines vascular endothelial growth factor and tumor necrosis factor-α.. Our study provides evidence that enalapril inhibits Ti particle-induced inflammatory osteolysis, and it may be a potentially useful treatment for aseptic loosening. Topics: Animals; China; Disease Models, Animal; Enalapril; Female; Inflammation; Mice; Mice, Inbred BALB C; Osteoclasts; Osteolysis; Prostheses and Implants; Prosthesis Failure; Titanium; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A | 2020 |
Açaí seed extract prevents the renin-angiotensin system activation, oxidative stress and inflammation in white adipose tissue of high-fat diet-fed mice.
The role of the renin-angiotensin system (RAS), oxidative stress, and inflammation on the development of obesity and its comorbidities has been extensively addressed. Euterpe oleracea Mart. (açaí) seed extract (ASE), with antioxidant and anti-inflammatory properties and capable to modulate plasma renin levels, has been evidenced as a potential regulator of body mass. We hypothesized that the supplementation with ASE might exert beneficial effects on obesity-related white adipose tissue changes and metabolic disorders by interfering with the local adipose tissue overexpression of RAS, inflammation, and oxidative stress in C57BL/6 mice fed a high-fat (HF) diet. The animals were fed a standard diet (10% fat, control), 60% fat (HF), HF + ASE (300 mg/kg per day) and HF + ENA (enalapril, 30 mg/kg per day) for 12 weeks. ASE and ENA prevented weight gain and adiposity, adipocyte hypertrophy, dyslipidemia, and insulin resistance. In adipose tissue, ASE increased the insulin receptor expression and reduced renin and AT1 receptor expression, which was associated with decreased plasma levels of renin and angiotensin II. Differently, ENA increased the expression of angiotensin-conversing enzyme 2, AT2, B2, and Mas receptors in adipose tissue. Also, ASE but not ENA decreased malondialdehyde and 8-isoprostane levels in adipose tissue. Finally, ASE and ENA reduced the adipose tissue inflammatory markers tumor necrosis factor alpha and interleukin 6. These results demonstrate that ASE prevented the adipocyte hypertrophy, obesity, hyperlipidemia, hyperglycemia, and insulin resistance in HF diet-fed mice. The downregulation of RAS in adipose tissue, reducing oxidative stress and inflammation, may contribute to the prevention of obesity-related disorders. Topics: Adipocytes; Adipose Tissue; Adipose Tissue, White; Angiotensin-Converting Enzyme Inhibitors; Animals; Blood Glucose; Blood Pressure; Body Weight; Diet, High-Fat; Eating; Enalapril; Energy Intake; Euterpe; Inflammation; Insulin; Lipids; Male; Mice; Mice, Inbred C57BL; Oxidative Stress; Plant Extracts; Renin-Angiotensin System; Seeds | 2020 |
Tangeretin ameliorates renal failure via regulating oxidative stress, NF-κB-TNF-α/iNOS signalling and improves memory and cognitive deficits in 5/6 nephrectomized rats.
Chronic kidney disease (CKD) is a significant global health concern with limited treatment options. Oxidative stress and inflammatory responses have been implicated in the pathology of CKD. Patients with CKD are frequently affected with neurological complications that affect both the central and peripheral nervous system. Identification of effective treatment strategies are of much clinical value in the therapy of CKD. Tangeretin, a plant-derived flavonoid has been described to retain extensive pharmacological properties. In the present study, we explored whether tangeretin exerted protective effects in 5/6 nephrectomized rats. CKD was induced in Sprague-Dawley rats by 5/6 nephrectomy (Nx). Separate groups of 5/6 Nx rats were treated with tangeretin (50, 100 or 200 mg/kg b.wt.) or enalapril for 30 days (starting 5 days after surgery for 35 days). Control animals were not subjected to Nx nor were treated with tangeretin or enalapril. Renal dysfunction, as evinced by raised serum urea, serum creatinine, proteinuria, and histological alterations were significantly reduced by tangeretin and enalapril treatment. 5/6 Nx animals exhibited raised levels of malondialdehyde (MDA) and reactive oxygen species. Elevated TNF-α, nitric oxide (NO) and cytokines-IL-6 and IL-1β with upregulated NF-κB/TNF-α/iNOS signalling pathways were effectively down-regulated by tangeretin. Cognitive disturbances and memory impairments observed in Nx rats were substantially improved by tangeretin. Collectively, the experimental data indicate that the anti-oxidant and anti-inflammatory effects of tangeretin effectively improved renal function and reduced the cognitive and memory impairments in CKD-induced animals. Topics: Animals; Cognition; Cognition Disorders; Cytokines; Disease Models, Animal; Down-Regulation; Enalapril; Flavones; Inflammation; Kidney; Male; Memory; Nephrectomy; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Rats; Rats, Sprague-Dawley; Renal Insufficiency; Renal Insufficiency, Chronic; Signal Transduction; Tumor Necrosis Factor-alpha; Up-Regulation | 2018 |
Enalapril in Combination with Benznidazole Reduces Cardiac Inflammation and Creatine Kinases in Mice Chronically Infected with Trypanosoma cruzi.
The protozoan Trypanosoma cruzi triggers an inflammatory process in mammalian heart causing events such as fibrosis, changes in the architecture and functionality in this organ. Enalapril, an angiotensin II-converting enzyme inhibitor, is a drug prescribed to ameliorate this heart dysfunction, and appears to exert a potential role in immune system regulation. Our aim was to evaluate the chronic cardiac inflammatory parameters after therapeutic treatment with enalapril and benznidazole in C57BL/6 mice infected with the VL-10 strain of T. cruzi. After infection, animals were treated with oral doses of enalapril (25 mg/kg), benznidazole (100 mg/kg), or both during 30 days. Morphometric parameters and levels of chemokines (CCL2, CCL5), IL-10, creatine kinases (CKs), and C-reactive protein were evaluated in the heart and serum at the 120th day of infection. Enalapril alone or in combination with benznidazole did not change the number of circulating parasites, but reduced cardiac leukocyte recruitment and total collagen in the cardiac tissue. Interestingly, the combination therapy (enalapril/benznidazole) also reduced the levels of chemokines, CK and CK-MB, and C-reactive proteins in chronic phase. In conclusion, during the chronic experimental T. cruzi infection, the combination therapy using enalapril plus benznidazole potentiated their immunomodulatory effects, resulting in a low production of biomarkers of cardiac lesions. Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Chagas Cardiomyopathy; Enalapril; Inflammation; Male; Mice; Mice, Inbred C57BL; Nitroimidazoles; Trypanocidal Agents; Trypanosoma cruzi | 2015 |
Enalapril inhibits tubulointerstitial inflammation and NLRP3 inflammasome expression in BSA-overload nephropathy of rats.
Proteinuria is not only a common marker of renal disease, but also involved in renal tubulointerstitial inflammation and fibrosis. The aim of this study was to investigate the mechanisms underlying the protective effects of enalapril, an ACEI, against nephropathy in rats.. Wistar rats underwent unilateral right nephrectomy, and then were treated with BSA (5 g·kg(-1)·d(-1), ip), or BSA plus enalapril (0.5 g·kg(-1)·d(-1), po) for 9 weeks. The renal lesions were evaluated using histology and immunohistochemistry. The expression of NLRP3, caspase-1, IL-1β and IL-18 was analyzed using immunohistochemistry, RT-PCR and Western blot.. BSA-overload resulted in severe proteinuria, which peaked at week 7, and interstitial inflammation with prominent infiltration of CD68(+) cells (macrophages) and CD3(+) cells (T lymphocytes), particularly of CD20(+) cells (B lymphocytes). BSA-overload markedly increased the expression of NLRP3, caspase-1, IL-1β and IL-18 in the proximal tubular epithelial cells, and in inflammatory cells as well. Furthermore, the expression of IL-1β or IL-18 was significantly correlated with proteinuria (IL-1β: r=0.757; IL-18: r=0.834). These abnormalities in BSA-overload rats were significantly attenuated by concurrent administration of enalapril.. Enalapril exerts protective effects against BSA-overload nephropathy in rats via suppressing NLRP3 inflammasome expression and tubulointerstitial inflammation. Topics: Animals; B-Lymphocytes; Carrier Proteins; Caspase 1; Enalapril; Epithelial Cells; Inflammasomes; Inflammation; Interleukin-18; Interleukin-1beta; Kidney Tubules, Proximal; Macrophages; Male; Nephrectomy; Nephritis, Interstitial; NLR Family, Pyrin Domain-Containing 3 Protein; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear; Serum Albumin, Bovine; T-Lymphocytes | 2014 |
Differential gene expression profiles in spontaneously hypertensive rats induced by administration of enalapril and nifedipine.
Enalapril and nifedipine are used as antihypertensive drugs; however, the therapeutic target molecules regulated by enalapril and nifedipine have yet to be fully identified. The aim of this study was to identify novel target genes that are specifically regulated by enalapril and nifedipine in tissues from spontaneously hypertensive rats (SHR) using DNA microarray analysis. We found that administration of SHR with enalapril and nifedipine differentially regulated 33 genes involved in the pathogenesis of cardiovascular diseases. Furthermore, we identified 16 genes that have not previously been implicated in cardiovascular diseases, including interleukin-24 (IL-24). Among them, exogenous administration of IL-24 attenuated the expression of vascular inflammation and hypertension-related genes induced by H2O2 treatment in mouse vascular smooth muscle (MOVAS) cells. This study provides valuable information for the development of novel antihypertensive drugs. In addition, the genes identified may be of use as biomarkers and therapeutic targets for cardiovascular diseases, including hypertension. Topics: Animals; Antihypertensive Agents; Blood Pressure; Brain; Enalapril; Heart; Hydrogen Peroxide; Hypertension; Inflammation; Interleukins; Liver; Male; Mice; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nifedipine; Oligonucleotide Array Sequence Analysis; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Transcriptome | 2013 |
Curcumin and enalapril ameliorate renal failure by antagonizing inflammation in 5/6 nephrectomized rats: role of phospholipase and cyclooxygenase.
Previously, we showed that curcumin prevents chronic kidney disease (CKD) development in ⅚ nephrectomized (Nx) rats when given within 1 wk after Nx (Ghosh SS, Massey HD, Krieg R, Fazelbhoy ZA, Ghosh S, Sica DA, Fakhry I, Gehr TW. Am J Physiol Renal Physiol 296: F1146-F1157, 2009). To better mimic the scenario for renal disease in humans, we began curcumin and enalapril therapy when proteinuria was already established. We hypothesized that curcumin, by blocking the inflammatory mediators TNF-α and IL-1β, could also reduce cyclooxygenase (COX) and phospholipase expression in the kidney. Nx animals were divided into untreated Nx, curcumin-treated, and enalapril-treated groups. Curcumin (75 mg/kg) and enalapril (10 mg/kg) were administered for 10 wk. Renal dysfunction in the Nx group, as evidenced by elevated blood urea nitrogen, plasma creatinine, proteinuria, segmental sclerosis, and tubular dilatation, was comparably reduced by curcumin and enalapril, with only enalapril significantly lowering blood pressure. Compared with controls, Nx animals had higher plasma/kidney TNF-α and IL-1β, which were reduced by curcumin and enalapril treatment. Nx animals had significantly elevated kidney levels of cytosolic PLA(2), calcium-independent intracellular PLA(2), COX 1, and COX 2, which were comparably reduced by curcumin and enalapril. Studies in mesangial cells and macrophages were carried out to establish that the in vivo increase in PLA(2) and COX were mediated by TNF-α and IL-1β and that curcumin, by antagonizing the cytokines, could significantly reduce both PLA(2) and COX. We conclude that curcumin ameliorates CKD by blocking inflammatory signals even if it is given at a later stage of the disease. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antihypertensive Agents; Curcumin; Enalapril; Inflammation; Inflammation Mediators; Interleukin-1beta; Kidney; Nephrectomy; Phospholipases; Prostaglandin-Endoperoxide Synthases; Rats; Renal Insufficiency; Tumor Necrosis Factor-alpha | 2012 |
Inhibiting TGF-β activity improves respiratory function in mdx mice.
Respiratory function is the main cause of mortality in patients with Duchenne muscular dystrophy (DMD). Elevated levels of TGF-β play a key role in the pathophysiology of DMD. To determine whether therapeutic attenuation of TGF-β signaling improves respiratory function, mdx mice were treated from 2 weeks of age to 2 months or 9 months of age with either 1D11 (a neutralizing antibody to all three isoforms of TGF-β), losartan (an angiotensin receptor antagonist), or a combination of the two agents. Respiratory function was measured in nonanesthetized mice by plethysmography. The 9-month-old mdx mice had elevated Penh values and decreased breathing frequency, due primarily to decreased inspiratory flow rate. All treatments normalized Penh values and increased peak inspiratory flow, leading to decreased inspiration times and breathing frequency. Additionally, forelimb grip strength was improved after 1D11 treatment at both 2 and 9 months of age, whereas, losartan improved grip strength only at 2 months. Decreased serum creatine kinase levels (significant improvement for all groups), increased diaphragm muscle fiber density, and decreased hydroxyproline levels (significant improvement for 1D11 only) also suggested improved muscle function after treatment. For all endpoints, 1D11 was equivalent or superior to losartan; coadministration of the two agents was not superior to 1D11 alone. In conclusion, TGF-β antagonism may be a useful therapeutic approach for treating DMD patients. Topics: Animals; Biomarkers; Body Weight; Cell Adhesion Molecules; Creatine Kinase; Diaphragm; Dose-Response Relationship, Drug; Enalapril; Gene Expression Regulation; Hand Strength; Hydroxyproline; Inflammation; Losartan; Mice; Mice, Inbred mdx; Muscle Fibers, Skeletal; Myogenin; Organ Size; Respiration; Respiratory Function Tests; RNA, Messenger; Transforming Growth Factor beta | 2011 |
Temporal increases in subclinical levels of inflammation are associated with adverse clinical outcomes in patients with left ventricular dysfunction.
The implication of various cytokines in a subclinical inflammatory process has been documented in heart failure (HF). The role of temporal changes of more conventional markers of inflammation, such as the white blood cell (WBC) count, on clinical outcomes remains largely unknown.. We performed a retrospective analysis of patients included in the Studies Of Left Ventricular Dysfunction that had documented eligibility at the baseline visit, a documented WBC count at baseline and at least 1 measurement during follow-up. We evaluated the association between variations in WBC count, WBC subfractions and mortality and non-fatal events. An increase in WBC count during follow-up compared with baseline was associated with a significantly higher risk of all-cause and cardiovascular (CV) mortality, HF mortality and arrhythmic death (all P < .05). A relative increase in the neutrophil count was associated with higher risk of all-cause and CV mortality, HF mortality and cardiac ischemic events (all P < .05). No significant interaction was present in regards to the etiology of HF.. Temporal increases in WBC and neutrophil counts are associated with increased risks of death and CV events. This relationship appears to be independent of HF etiology. Topics: Aged; Blood Cell Count; Cardiovascular Diseases; Enalapril; Female; Follow-Up Studies; Humans; Inflammation; Leukocyte Count; Lymphocyte Count; Male; Middle Aged; Neutrophils; Prognosis; Retrospective Studies; Risk Assessment; Time Factors; Ventricular Dysfunction, Left | 2006 |
Dual angiotensin-converting enzyme/neutral endopeptidase inhibition on cardiac and renal fibrosis and inflammation in DOCA-salt hypertensive rats.
The relative roles of angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) inhibition on cardiac and renal fibrosis in deoxycorticosterone acetate (DOCA)-salt hypertensive rats were studied.. The ACE/NEP inhibitor omapatrilat (40 mg/kg per day), the ACE inhibitor enalapril (10 mg/kg per day) and the NEP inhibitor CGS 25462(100 mg/kg per day) were administrated for 3 weeks to DOCA rats. Collagen was stained with Sirius red, and mediators of inflammation were identified by immunolabeling (vascular cell adhesion molecule, nuclear factor-kappaB, infiltrating ED-1-positive macrophages and monocyte chemotactic protein-1) or by western blot (platelet-endothelial cell adhesion molecule-1).. Elevated systolic blood pressure of DOCA rats was significantly reduced (P < 0.05) by omapatrilat and CGS 25462. Omapatrilat and CGS 25462 significantly (P < 0.05) decreased interstitial collagen density in the left ventricle of DOCA rats compared with untreated DOCA rats. Enalapril only decreased the subepicardial collagen of DOCA rats. Omapatrilat significantly (P < 0.05) decreased renal mesangial collagen deposition in DOCA rats. Cardiac and renal expression of surface adhesion molecules, nuclear factor-kappaB, monocyte chemotactic protein and ED-1-positive cells were decreased in omapatrilat-treated DOCA rats compared with untreated DOCA rats. Enalapril and CGS 25462 did not alter mesangial collagen of DOCA rats.. Dual ACE/NEP inhibition was more effective than ACE or NEP inhibition in decreasing inflammatory mediators, and improving cardiac and renal fibrosis. This suggests a role for NEP inhibition added to blockade of the renin-angiotensin system that may explain the greater efficacy of omapatrilat. Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Biphenyl Compounds; Blood Pressure; Cell Adhesion Molecules; Collagen; Desoxycorticosterone; Drug Therapy, Combination; Enalapril; Fibrosis; Heart Diseases; Hypertension; Inflammation; Kidney Diseases; Metalloendopeptidases; Neprilysin; NF-kappa B; Organophosphonates; Pyridines; Rats; Rats, Sprague-Dawley; Thiazepines | 2005 |
Glomerular activin A overexpression is linked to fibrosis in anti-Thy1 glomerulonephritis.
Activin A, a member of the transforming growth factor-beta (TGF-beta) superfamily of proteins, shares many biological features with the pro-fibrotic cytokine TGF-beta1, which is primarily responsible for the accumulation of extracellular matrix proteins in renal disease. This study was designed to identify regulators of activin A production in glomerular mesangial cells and test if activin A acts as a pro-fibrotic cytokine in mesangial cells.. The effect of inflammatory cytokines on activin A production and the effect of exogenous activin A on mediators of fibrosis were analysed in cultured rat mesangial cells. Expression of activin A and of established mediators of fibrosis was analysed in a rat model of glomerular fibrosis (anti-Thy1 glomerulonephritis).. In cultured mesangial cells, interleukin-1 and basic fibroblast growth factor, both mediators of glomerular inflammatory injury, dose-dependently increased activin A expression. Incubation with activin A significantly stimulated TGF-beta1, PAI-1 and connective tissue growth factor RNA expression and increased production of extracellular matrix proteins in mesangial cells. In rats with anti-Thy1 glomerulonephritis, expression of glomerular activin A mRNA and protein paralled the expression of TGF-beta and other indices of fibrosis, showing little change from normal on day 1, a marked, 70-fold increase of activin protein production on day 6, and a subsequent decrease at day 12. Antifibrotic therapy with the angiotensin-converting enzyme inhibitor enalapril significantly reduced glomerular activin A production.. Taken together, the results of this study link overexpression of activin A to glomerular matrix protein expansion in vivo and in vitro, suggesting that activin A acts as pro-fibrotic cytokine in renal disease. Topics: Activins; Animals; Cells, Cultured; Disease Models, Animal; Enalapril; Fibroblast Growth Factor 2; Gene Expression Regulation; Glomerular Mesangium; Inflammation; Inhibin-beta Subunits; Interleukin-1; Male; Rats; Rats, Sprague-Dawley; Reference Values; Reverse Transcriptase Polymerase Chain Reaction; Transcription, Genetic; Transforming Growth Factor beta; Transforming Growth Factor beta1 | 2005 |
The inhibitory effect of alacepril, an angiotensin-converting enzyme inhibitor, on endothelial inflammatory response induced by oxysterol and TNF-alpha.
The objectives were to determine the effects of alacepril, an angiotensin-converting enzyme inhibitor, on the expression of adhesion molecules and monocyte adherence to endothelial cells induced by 7-ketocholesterol (7-KC) and tumor necrosis factor (TNF)-alpha. We used human aortic endothelial cells (HAECs) and U937 monocytic cells. Surface expression and mRNA levels of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) were determined by EIA and RT-PCR. Adherence of U937 to HAECs was assessed by adhesion assay. Incubation of HAEC with 7-KC increased the surface expression of protein and mRNA levels of ICAM-1 and VCAM-1 on HAECs and the production of reactive oxygen species (ROS) in HAECs. Pretreatment with alacepril reduced the enhanced expression of these molecules in a dose-dependent manner. The inhibitory effect of alacepril against 7-KC or TNF-alpha-induced CAMs expression was stronger than that of captopril or enalapril. Alacepril inhibited the production of ROS in HAECs stimulated by 7-KC or TNF-alpha. These results suggest that alacepril works as anti-atherogenic agent through inhibiting endothelial-dependent adhesive interactions with monocytes induced by 7-KC and TNF-alpha. Topics: Angiotensin-Converting Enzyme Inhibitors; Captopril; Cell Adhesion; Dose-Response Relationship, Drug; Enalapril; Endothelium, Vascular; Inflammation; Intercellular Adhesion Molecule-1; Ketocholesterols; Monocytes; Reactive Oxygen Species; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1 | 2004 |
Osteogenic protein-1 prevents renal fibrogenesis associated with ureteral obstruction.
Unilateral ureteral obstruction (UUO) is a model of renal injury characterized by progressive tubulointerstitial fibrosis and renal damage, while relatively sparing the glomerulus and not producing hypertension or abnormalities in lipid metabolism. Tubulointerstitial fibrosis is a major component of several kidney diseases associated with the progression to end-stage renal failure. Here we report that when a critical renal developmental morphogen, osteogenic protein-1 (OP-1; 100 or 300 microg/kg body wt), is administered at the time of UUO and every other day thereafter, interstitial inflammation and fibrogenesis are prevented, leading to preservation of renal function during the first 5 days after obstruction. Compared with angiotensin-converting enzyme inhibition with enalapril treatment, OP-1 was more effective in preventing tubulointerstitial fibrosis and in preserving renal function. The mechanism of OP-1- induced renal protection was associated with prevention of tubular atrophy, an effect not shared with enalapril, and was related to preservation of tubular epithelial integrity. OP-1 blocked the stimulation of epithelial cell apoptosis produced by UUO, which promoted maintenance of tubular epithelial integrity. OP-1 preserved renal blood flow (RBF) during UUO, but enalapril also stimulated RBF. Thus OP-1 treatment inhibited tubular epithelial disruption stimulated by the renal injury of UUO, preventing tubular atrophy and diminishing the activation of tubulointerstitial inflammation and fibrosis and preserving renal function. Topics: Actins; Angiotensin-Converting Enzyme Inhibitors; Animals; Apoptosis; Atrophy; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Cell Size; Collagen; Enalapril; Epithelial Cells; Fibrosis; Immunohistochemistry; Inflammation; Kidney; Macrophages; Rats; Rats, Sprague-Dawley; Renal Circulation; Transforming Growth Factor beta; Ureteral Obstruction | 2000 |
Interrelationship of the kinin system, nitric oxide and eicosanoids in the antigen-induced arthritis in rabbits.
The aim of the present study was to investigate the interrelationship of the kinin system, nitric oxide and eicosanoids in the acute phase of antigen-induced arthritis (AIA) in rabbits. The arthritis was induced in immunized rabbits and the following parameters were evaluated 24 hours later: leukocyte influx (total and differential white cell count), vascular permeability (Evans's blue method), and synovial PMN cell infiltrate. PGE2 and LTB4 (radioimmunoassay) levels were quantified in the synovial fluid. The animals were pre-treated with 20mg/kg/day during 14 days with L-NAME or D-NAME and/or Enalapril (0.12 mg/kg/day-14 days), and/or the B2 antagonist of Bradykinin HOE 140 (0.9 mg/kg). Our results showed that L-NAME was effective in the prevention of AIA with reduction of all Inflammatory parameters analyzed. Enalapril partially reverted the L-NAME anti-inflammatory effects. The simultaneous treatment with HOE 140 abolished this reversion and returned the inflammatory parameters to the levels observed in L-NAME treated animals. Our results suggest that pressoric alterations induced by L-NAME could not account for all its anti-inflammatory action in this model of experimental arthritis. Additionally the contribution of the kinin system in AIA was characterized as well as its interaction with eicosanoids and nitric oxide. Topics: Animals; Arthritis, Experimental; Bradykinin; Bradykinin Receptor Antagonists; Capillary Permeability; Eicosanoids; Enalapril; Inflammation; Kinins; Leukocyte Count; Male; Neutrophils; NG-Nitroarginine Methyl Ester; Nitric Oxide; Rabbits; Receptor, Bradykinin B2; Synovial Fluid | 1999 |
[(1H-imidazol-1-yl)methyl]- and [(3-pyridinyl)methyl]pyrroles as thromboxane synthetase inhibitors.
Several [(1H-imidazol-1-yl)methyl]- and [(3-pyridinyl)methyl] pyrroles were prepared and evaluated in vitro as thromboxane synthetase inhibitors in human platelet aggregation studies. A number of structures, e.g. 10b,f,g,i (respective IC50 values: 1 microM, 50 nM, 42 nM, 44 nM) showed superior in vitro inhibition of TXA2 synthetase when compared to the standard dazoxiben (1). However, it was found that in vitro potency did not translate into nor correlate with in vivo activity when these compounds were evaluated in mice in a collagen-epinephrine-induced pulmonary thromboembolism model. (E)-1-Methyl-2-[(1H-imidazol-1-yl)methyl]-5-(2-carboxyprop-1-enyl) pyrrole (10b) was found to offer protection against collagen-epinephrine-induced mortality in mice, thereby demonstrating that oral administration is an effective route for absorption of this drug. Additional evidence for the oral effectiveness of 10b in lowering serum TXB2 levels was obtained by performing ex vivo radioimmunoassay experiments with rats. A 13-week study of 10b in rats with reduced renal mass was conducted in order to evaluate the role of TXA2 production in hypertension and renal dysfunction. Although serum and urinary TXB2 levels in rats were found to be lowered during this study by 10b, the levels of urinary protein excretion remained comparable to that of the control group. Topics: Animals; Aorta; Biological Availability; Blood Platelets; Chemical Phenomena; Chemistry; Humans; Imidazoles; Inflammation; Kidney Diseases; Male; Mice; Microsomes; Platelet Aggregation Inhibitors; Prostaglandin Endoperoxides, Synthetic; Prostaglandin H2; Prostaglandins H; Pyridines; Pyrroles; Rats; Structure-Activity Relationship; Swine; Thromboxane A2; Thromboxane B2; Thromboxane-A Synthase | 1989 |
Effects of an alpha-2 adrenoceptor agonist on angiotensin converting enzyme inhibitor-induced hypotension and potentiated allergen-evoked inflammatory skin responses.
Angiotensin converting enzyme (ACE) inhibitors have been demonstrated to possess proinflammatory properties. Persistent cough and increased broncho-obstruction have been reported frequently in hypertensive subjects on ACE inhibitor therapy. We have studied the effect of an alpha-2 adrenoceptor agonist, clonidine, on MK 422 (active parent diacid of enalapril)-induced hypotension and potentiated inflammatory skin responses in ovalbumin-sensitized guinea pigs. Clonidine was found to abolish dose-dependently MK 422-potentiated ovalbumin-evoked inflammatory dermal responses and it possesses additive hypotensive effects when combined with the ACE inhibitor. It would therefore be interesting to evaluate further alpha-2 adrenoceptor agonists and ACE inhibitors in a combination therapy in humans when single drug antihypertensive therapy of the drugs is insufficient. Topics: Adrenergic alpha-Agonists; Allergens; Angiotensin-Converting Enzyme Inhibitors; Animals; Blood Pressure; Clonidine; Enalapril; Enalaprilat; Female; Guinea Pigs; Inflammation; Skin Tests | 1988 |
Impairment of granulomatous inflammatory response to Histoplasma capsulatum by inhibitors of angiotensin-converting enzyme.
Systemic infection with Histoplasma capsulatum induced a granulomatous inflammatory response in the lymphoreticular organs of C57BL/6 mice that was associated with elevated levels of angiotensin-converting enzyme (ACE) in the spleens. To determine the influence of ACE on the granulomatous response, either captopril or MK 421, two inhibitors of ACE, were administered intraperitoneally to mice 6 h after intravenous injection of H. capsulatum and then daily for 1 week. Each ACE inhibitor sharply reduced ACE activity in the spleens of infected mice. Both drugs worsened the clinical severity of infection and significantly increased the growth of H. capsulatum in livers and spleens of mice infected for 1 week. The histopathological changes in mice given captopril were more severe, with massive infiltrates of macrophages in proximity to large aggregates of yeasts. Conversely, the administration of captopril for 2 weeks during the resolving phases of infection did not slow the healing of the granulomatous lesions, nor did it provoke a relapse of infection. Captopril did not promote the growth of H. capsulatum in artificial medium. This drug was not cytotoxic to peripheral blood leukocytes or to splenic leukocytes from normal and infected mice. Administration of captopril to normal mice for 1 week did not depress the response of splenocytes of concanavalin A or to phytohemagglutinin, nor did it diminish delayed-type hypersensitivity responses in vivo. Finally, captopril did not augment the growth of H. capsulatum within macrophages. Our results suggest that ACE may participate in the regulation of the granulomatous inflammatory response to H. capsulatum and that ACE inhibition impairs the protective effects of granulomatous inflammation during acute H. capsulatum infection. Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Captopril; Dipeptides; Enalapril; Granuloma; Histoplasma; Histoplasmosis; Hypersensitivity, Delayed; Inflammation; Liver; Lymphocyte Activation; Macrophages; Male; Mice; Mice, Inbred C57BL; Peptidyl-Dipeptidase A; Proline; Spleen | 1985 |