leptin and Diabetic-Retinopathy

Diabetic retinopathy (DR) is a common complication of diabetes. The adipocytokines are closely associated with the occurrence and development of diabetes and its related complications. Literature confirms that the level of adiponectin in patients with DR is significantly higher; however, the relationship between other adipocytokines (leptin, chemerin, apelin, and omentin-1) and DR remains unclear.. This study aimed to systematically evaluate the association between adipocytokines (leptin, chemerin, apelin, and omentin-1) and DR.. The PubMed, Web of Science, Embase, EBSCO and Willy databases were used to search for potential studies with keywords such as "diabetic retinopathy" or "DR" in combination with the terms "leptin," "chemerin", "apelin" or "omentin-1" in the search titles or abstracts. Standardized mean differences (SMD) with corresponding 95% confidence intervals (CIs) were determined as the results of the meta-analysis.. After screening, 18 articles were included in the meta-analysis including 750 DR cases and 993 controls. Leptin and chemerin levels in patients with DR were significantly higher than those in the control group (SMD: 0.68, 95% CI [0.1, 1.26]; SMD: 0.79, 95% CI [0.35, 1.23]). The omentin-1 levels in patients with DR were significantly lower than those in the controls (SMD: -0.85, 95% CI [-1.08, -0.62]).. To the best of our knowledge, this is the first meta-analysis to evaluate the leptin, chemerin, apelin, and omentin-1 levels in patients with DR. Further high-quality studies are warranted to support the association between these adipocytokines and DR.. https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=443770, identifier CRD42023443770.

Topics: Adipokines; Adiponectin; Apelin; Diabetes Mellitus; Diabetic Retinopathy; Humans; Leptin

Stroke is an important cause of morbidity and mortality, and is an economic burden. Diabetes and obesity are two important modifiable risk factors for stroke. Patients with diabetes have a higher incidence of stroke and a poorer prognosis after stroke. Risk-factor modification is the most important aspect of prevention of stroke in diabetes and obesity. This includes lifestyle modifications and different therapeutic modalities to control conditions, such as diabetes, hypertension, dyslipidemia and arrhythmia. Recent landmark studies have shown the beneficial effects of statins in diabetic patients even with close to normal or normal low-density lipoprotein cholesterol. Obesity, which is a risk factor for diabetes, hypertension and hyperlipidemia has been shown to be an independent risk factor for stroke. Increased leptin, dysregulation of adipocyte proteins, increased insulin resistance and C-reactive protein may be factors involved in the increased incidence of cardiovascular morbidity and mortality directly related to obesity. Visceral fat is a much bigger health risk than subcutaneous fat. Lifestyle interventions and pharmacotherapeutic agents have been used to manage obesity. In morbidly obese patients, surgical intervention seems to be the best method of treatment with a long-lasting favorable metabolic outcome. In the 21st Century, with the advanced medical knowledge and the therapeutic modalities available, it should be possible to reduce the incidence of stroke associated with diabetes and obesity.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Atrial Fibrillation; Blood Glucose; Cardiovascular Agents; Carotid Stenosis; Diabetes Mellitus; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Dyslipidemias; Humans; Hypertension; Insulin Resistance; Ischemic Attack, Transient; Leptin; Life Style; Lipoproteins; Obesity; Plasminogen Activator Inhibitor 1; Risk Factors; Smoking; Stroke

The objective of this article is to evaluate the potential effects of beta-glucan and vitamin D supplementation in patients with diabetic retinopathy. We evaluated the levels of several parameters of inflammatory reactions (C-reactive protein [CRP], serum amyloid A [SAA], and interleukin- [IL-] 6), leptin, and vitamin D. Using a 3-month interval, we divided the patients into three groups: (1) supplemented with beta-glucan and vitamin D, (2) supplemented with vitamin D and placebo, and (3) supplemented with vitamin D alone. By this division, we aim not only to observe whether beta-glucan can increase the effects of vitamin D, but also to eliminate the potential effects of placebo. The doses of vitamin D corresponded to phototype, weight, age, and sex of the individual. Fifty-two diabetic retinopathy patients were selected for our study. We found significant vitamin D deficits in all cases, even after three months of supplementation with vitamin D. Significant changes in levels of CRP were observed in the beta-glucan-supplemented group; levels of SAA and IL-6 were not changed. Leptin levels were significantly lowered in the beta-glucan-supplemented group and increased in the other groups. More detailed studies and/or longer supplementation is necessary.

Topics: Aged; Aged, 80 and over; beta-Glucans; Body Mass Index; C-Reactive Protein; Czech Republic; Diabetic Retinopathy; Female; Humans; Inflammation; Interleukin-6; Leptin; Male; Middle Aged; Placebos; Serum Amyloid A Protein; Vitamin D; Vitamin D Deficiency

Accumulating evidence has suggested a link between adipokines and diabetic retinopathy (DR). This study is aimed at investigating the risk factors for sight-threatening DR (STDR) and establishing a prognostic model for predicting STDR among a high-risk population of patients with type 2 diabetes mellitus (T2DM).. Plasma concentrations of adipokines were determined by enzyme-linked immunosorbent assay. In the case-control set, principal component analysis (PCA) was performed to select optimal predictive cytokines for STDR, involving severe nonproliferative DR (NPDR) and proliferative DR. Support vector machine (SVM) was used to examine the possible combination of baseline plasma adipokines to discriminate the patients with mild NPDR who will later develop STDR. An individual prospective cohort with a follow-up period of 3 years was used for the external validation.. In both training and testing sets, involving 306 patients with T2DM, median levels of plasma adiponectin (APN), leptin, and fatty acid-binding protein 4 (FABP4) were significantly higher in the STDR group than those in mild NPDR. Except for adipsin, the other three adipokines, FABP4, APN, and leptin, were selected by PCA and integrated into SVM. The accuracy of the multivariate SVM classification model was acceptable in both the training set (AUC = 0.81, sensitivity = 71%, and specificity = 91%) and the testing set (AUC = 0.77, sensitivity = 61%, and specificity = 92%). 110 T2DM patients with mild NPDR, the high-risk population of STDR, were enrolled for external validation. Based on the SVM, the risk of each patient was calculated. More STDR occurred in the high-risk group than in the low-risk group, which were grouped by the median value of APN, FABP4, and leptin, respectively. The model was validated in an individual cohort using SVM with the AUC, sensitivity, and specificity reaching 0.77, 64%, and 91%, respectively.. Adiponectin, leptin, and FABP4 were demonstrated to be associated with the severity of DR and maybe good predictors for STDR, suggesting that adipokines may play an important role in the pathophysiology of DR development.

Topics: Adipokines; Adiponectin; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Humans; Leptin; Prospective Studies

To investigate serum leptin levels in patients with type 2 diabetes mellitus (T2DM) and the relationship between leptin levels and T2DM complications and prevalence.. A total of 355 patients, 282 cases with T2DM and 73 normal controls, were recruited at 1st Medical Centre, Chinese PLA General Hospital (Beijing, China) between November 2013 and July 2014. Levels of serum leptin, biochemical markers and sexual hormones were measured, and clinical characteristics were retrieved through the electronic medical record system.. Leptin levels in females were higher than that in males. Leptin levels in T2MD patients were positively correlated with body mass index, percent body fat, triglyceride, cystatin C homocysteine and salivary acid, and negatively correlated with glycosylated serum protein and glycosylated albumin levels. Leptin levels in males were positively correlated with systolic pressure and estradiol, and negatively correlated with testosterone and high density lipoprotein cholesterol. Sex (female) was positively correlated with the duration of disease. Leptin levels in T2DM patients with complications such as hypertension, diabetic nephropathy, diabetic peripheral neuropathy and coronary heart disease were higher than that in patients without such complications. Leptin levels in females with diabetic retinopathy and diabetic macroangiopathy were higher than that in patients without such complications, but there was no difference in males.. Leptin has significant gender differences. Leptin levels are related to body mass index, percent body fat and sex hormone level in T2DM patients and may affect short-term blood glucose control in T2DM patients. Leptin levels are related to complications in patients with T2DM and affect the prevalence rates of complications.

Topics: Albumins; Biomarkers; Body Mass Index; Cholesterol, HDL; Cystatin C; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Estradiol; Female; Homocysteine; Humans; Leptin; Male; Polyesters; Testosterone; Triglycerides

In our study, we focused on possible effects of supplementation with glucan and vitamin D on total numbers of NK cells in patients with diabetic retinopathy. We evaluated possible relations among nutritional state (BMI), leptin levels, and total numbers of NK cells in patients supplemented with (1) glucan and vitamin D, (2) vitamin D and placebo, and (3) vitamin D alone. Our results show that 3 months of supplementation with both glucan and vitamin D resulted in significant improvements of NK cell numbers. In addition, we found statistically significant correlation between NK cell numbers and leptin levels. Based on these results, we propose that the molecule responsible for these changes is glucan, as vitamin D alone or together with placebo caused no effects.

Topics: Aged; beta-Glucans; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Dietary Supplements; Female; Humans; Immunomodulation; Killer Cells, Natural; Leptin; Lymphocyte Count; Male; Middle Aged; Vitamin D

The link between diabetic retinopathy (DR) and adipokines is controversial. Some studies suggest that visceral fat and adipokines could be additional risk factors for DR. The aim of this study was to determine the relationship between abdominal fat or adipokine secretion and DR in patients with type 2 diabetes mellitus (DM).. A total of 179 patients with type 2 DM were included. Each patient underwent measurement of plasma adiponectin and leptin and an evaluation of body fat distribution (visceral and subcutaneous) with MRI. The severity of DR was evaluated according to the classification of the American Academy of Ophthalmology. Patients were classified in 3 groups: absence of DR, mild and moderate DR, and advanced DR (severe, proliferative and laser-treated DR).. There were no significant differences between the 3 groups for adiponectin, leptin and visceral or subcutaneous fat accumulation. Patients with DR had a mean duration of diabetes, serum creatinine concentration and percentage of macroalbuminuria significantly higher than patients without DR (p < 0.001, p = 0.003 and p < 0.001, respectively). Serum adiponectin increased with the diabetic nephropathy stage (p = 0.007).. Our study suggests that body fat distribution and adipokine secretion are not associated with DR in patients with type 2 DM.

Topics: Adiponectin; Adult; Aged; Aged, 80 and over; Albuminuria; Body Fat Distribution; Creatinine; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Humans; Leptin; Magnetic Resonance Imaging; Male; Middle Aged

The pathogenesis of diabetic retinopathy (DR) in metabolic syndrome (MetS) and type 2 diabetes (T2D) is not well studied, partly because an appropriate model has not been developed. Recently, we introduced a novel model of spontaneous T2D and MetS that replicates the relevant features of the human disease. In the current study, we investigated the retinal vascular changes in these animals. Experimental DR in streptozotocin (STZ)-injected rodents is described as an inflammatory disease, in which intercellular adhesion molecule 1 (ICAM-1) plays a key role. In comparison, advanced diabetes (HbA1c>10%) in the Nile grass rat (NGR) was associated with lower ICAM-1 protein expression when compared with that in normal or moderately diabetic animals. Vascular cell adhesion molecule 1 (VCAM-1) expression, however, was unaffected by the disease state. As opposed to the STZ-induced model of DR, in diabetic NGRs, most leukocytes accumulated in the retinal arteries. Consistent with the ICAM-1 reduction, leukocyte accumulation was significantly reduced in advanced disease. Similarly, leukocyte adhesions were significantly lower, with elevated plasma triglycerides (>200 mg/dl), and cholesterol (>240 mg/dl). However, these adhesions were significantly higher in animals with higher plasma insulin (>5 μIU/ml) and leptin (>20 ng/ml), suggesting a role for these hormones in diabetic retinal leukostasis. Diabetic NGRs showed substantial retinal endothelial injury, primarily in the microvessels, including vascular tortuosity, obliterated acellular capillaries, and pericyte ghosts. The NGR provides a convenient and realistic model for investigation of retinal changes in MetS/T2D with convincing advantages over the commonly used STZ-induced T1D.

Topics: Adiponectin; Animals; Blood-Retinal Barrier; Cell Adhesion; Diabetes Complications; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Disease Models, Animal; Female; Glycated Hemoglobin; Inflammation; Insulin; Intercellular Adhesion Molecule-1; Leptin; Leukocytes; Lipids; Male; Metabolic Syndrome; Rats; Retina; Retinal Vessels; Streptozocin; Triglycerides; Vascular Cell Adhesion Molecule-1

Inflammatory processes contribute to both diabetes and cardiovascular risk. We wanted to investigate whether circulating concentrations of proinflammatory immune mediators and adiponectin in diabetic patients are associated with incident cardiovascular events.. In 1,038 participants with diabetes of the population-based ESTHER study, of whom 326 showed signs of renal dysfunction, Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs for the association of increasing concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), IL-18, macrophage migration inhibitory factor (MIF), adiponectin, and leptin with cardiovascular events (myocardial infarction, stroke, or fatal cardiovascular event) during a follow-up period of 8 years.. During follow-up, 161 subjects with diabetes experienced a primary cardiovascular event. Proinflammatory markers were not associated with a higher risk for primary cardiovascular events in the total study population after adjustment for multiple confounders. However, IL-6 and MIF were associated with cardiovascular events in subjects with renal dysfunction (HR for the comparison of top vs. bottom tertile 1.98 [95% CI 1.12-3.52], P [trend] = 0.10 for IL-6; 1.48 [0.87-2.51], P [trend] = 0.04 for MIF). Adiponectin levels were associated with cardiovascular events in the total population (1.48 [1.01-2.21], P [trend] = 0.03), and the association was even more pronounced in the subgroup with renal dysfunction (1.97 [1.08-3.57], P [trend] = 0.02).. In particular, the absence of an association between CRP and a U-shaped association of adiponectin levels with incident cardiovascular events show that associations between circulating immune mediators and cardiovascular risk differ between diabetic patients and subjects of the general population.

Topics: Adiponectin; Aged; C-Reactive Protein; Cardiovascular Diseases; Cytokines; Diabetic Retinopathy; Female; Humans; Interleukin-18; Interleukin-6; Leptin; Macrophage Migration-Inhibitory Factors; Male; Middle Aged; Proportional Hazards Models

The aim of this study was to investigate the relationship between plasma leptin levels and the chronic complications in type 2 diabetic (T2DM) patients.. There were 157 T2DM patients (age, 56.7 ± 11.4 years; mean diabetes duration, 8.9 ± 3.6 years; mean body mass index, 28.1 ± 4.3 kg/m(2)) included to the study. Microvascular and macrovascular complications of diabetes were evaluated in all patients. There were 46 healthy subjects as control group. Plasma leptin levels were measured in both diabetic and healthy subjects.. Plasma leptin levels of the diabetic patients were not significantly different from the healthy subjects (26.4 ± 18.2 vs. 29.1 ± 13.1 ng/mL, P > 0.05). Plasma leptin levels in obese diabetic patients were higher than in nonobese (37.6 ± 20.9 vs. 20.0 ± 17.2 ng/mL, P = 0.001); in hypertensive diabetic patients than normotensive (35.2 ± 19.3 vs. 19.4 ± 13.9 ng/mL, P < 0.001); dyslipidemic diabetic patients than normolipidemic diabetic subjects (38.5 ± 18.3 vs. 31.3 ± 19.5 ng/mL, P = 0.038); diabetic patients with metabolic syndrome than diabetic patients without metabolic syndrome (37.9 ± 20.1 vs. 23.2 ± 15.3 ng/mL, P = 0.001). Plasma leptin levels were lower in diabetic patients who were smokers than nonsmokers (20.0 ± 15.5 vs. 24.7 ± 17.4 ng/mL, P = 0.023). There was no significant difference between patients with and without diabetic nephropathy, retinopathy, neuropathy, coronary artery disease or peripheral vascular disease (P > 0.05).. Our data suggest that obesity, hypertension, dyslipidemia, and metabolic syndrome in T2DM were associated with increased plasma leptin levels. We conclude that plasma leptin levels may not be strongly associated with microangiopathy and macroangiopathy in T2DM individuals.

Topics: Adult; Aged; Body Mass Index; Case-Control Studies; Chronic Disease; Diabetes Complications; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Leptin; Male; Middle Aged; Obesity

Topics: Adiponectin; Adult; Biomarkers; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Diet, Diabetic; Female; Humans; Insulin; Leptin; Lipodystrophy, Congenital Generalized

Previous studies have demonstrated that leptin is an angiogenic factor, and an increase in intravitreous leptin concentrations in diabetic patients with proliferative diabetic retinopathy (PDR) has also been described. The aim of the present study was to investigate the source of intravitreal leptin and to determine whether it is related to PDR activity.. Serum and vitreous fluid samples were obtained simultaneously at the time of vitreoretinal surgery from 25 patients with PDR and 32 nondiabetic patients with nonproliferative ocular diseases (controls). Both groups were matched by age, sex, and body mass index. Leptin levels were determined by ELISA.. We did not observe any significant differences in vitreal levels of leptin between diabetic patients with PDR and controls (4.22 [2.6-9.7] versus 3.49 [1.9-9.7] ng/mL; P = not significant). Leptin concentrations were lower in vitreous fluid than in serum samples from diabetic patients with PDR (P < 0.001) and controls (P < 0.001). A direct correlation between serum and vitreous leptin concentrations was detected in diabetic patients with PDR (r = 0.60; P = 0.01) and controls (r = 0.51; P = 0.01). Finally, we did not observe any relationship between intravitreous leptin levels and PDR activity.. The intraocular production of leptin is not critically involved in the etiopathogenesis of PDR. In addition, our results suggest that serum diffusion is a relevant source of leptin in vitreous fluid.

Topics: Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Enzyme-Linked Immunosorbent Assay; Female; Humans; Leptin; Male; Middle Aged; Vitreous Body

Diabetic retinopathy is the leading cause of new blindness in adults in developed countries. Leptin, an adipocyte-derived hormone, stimulates endothelial proliferation and angiogenesis. This study was designed to elucidate the pathophysiologic role of leptin in the progression of retinal neovascularization. Using the retinopathy of prematurity model, a mouse model of ischemia-induced retinal neovascularization, we have demonstrated more pronounced retinal neovascularization in 17-day-old transgenic mice overexpressing leptin than in age-matched wild-type littermates. Ischemia-induced retinal neovascularization was markedly suppressed in 17-day-old leptin-deficient ob/ob mice. Western blot analysis revealed that a biologically active leptin receptor isoform is expressed in mouse retinal endothelial cells. Leptin receptor expression was also detected in primary cultures of porcine retinal endothelial cells, where it upregulated vascular endothelial growth factor (VEGF) mRNA expression. This effect was thought to be mediated at least partly through the activation of signal transducers and activators of transcription (STAT)3, because adenoviral transfection of the dominant-negative form of STAT3 abolished the leptin-induced upregulation of VEGF mRNA expression in retinal endothelial cells. This study provides evidence that leptin stimulates the ischemia-induced retinal neovasucularization possibly through the upregulation of endothelial VEGF, thereby suggesting that leptin antagonism may offer a novel therapeutic strategy to prevent or treat diabetic retinopathy.

Topics: Animals; Diabetic Retinopathy; DNA-Binding Proteins; Female; Gene Expression; Ischemia; Leptin; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Oxygen; Pregnancy; Receptors, Cell Surface; Receptors, Leptin; Retinal Neovascularization; Retinal Vessels; RNA, Messenger; STAT3 Transcription Factor; Trans-Activators; Up-Regulation; Vascular Endothelial Growth Factor A

In advanced stages of diabetic retinopathy, new blood vessels are formed based on undefined mechanisms. Recently, leptin was shown to possess an angiogenic action in vitro and to induce neovascularization in vivo. The aim of the present study was to investigate the relationship between plasma leptin levels and the severity of diabetic retinopathy.. There were 70 patients with type 2 diabetes (age 47.9 +/- 9.7 years, BMI 26.4 +/- 3.3 kg/m2) who were seen in a retina outpatient clinic recruited and assigned to subgroups according to the stage of their diabetic retinopathy. There were 66 healthy volunteer subjects matched with the diabetic patients for age, BMI, and sex who served as control subjects (age 46.0 +/- 8.8 years, BMI 27.1 +/- 2.3 kg/m2). Fasting plasma leptin levels were measured.. Plasma leptin level of the diabetic patients was not significantly different from the control subjects. In patients with proliferative diabetic retinopathy (n = 17), the mean plasma level of leptin (16.1 +/- 9.2 ng/ml) was significantly higher than that in patients with nonproliferative retinopathy (n = 20) (11.5 +/- 3.5 ng/ml, P = 0.039) or patients without retinopathy (n = 33) (5.8 +/- 3.7 ng/ml, P = 0.001). The mean leptin level in patients with nonproliferative diabetic retinopathy was also significantly higher than that in patients without retinopathy (P = 0.002).. Our results show that the more advanced the diabetic retinopathy, the higher the plasma leptin levels, even after adjusting the leptin levels for BMI. The presence of such a positive correlation need not imply a causal relationship. Nevertheless, previously observed leptin-induced promotion of angiogenesis and neovascularization lends support to the possibility that leptin may play a role in the progression of human diabetic retinopathy to a proliferative phase. This possibility deserves further investigation.

Topics: Biomarkers; Blood Glucose; Blood Pressure; Creatinine; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Leptin; Male; Middle Aged; Radioimmunoassay; Reference Values

Leptin is a cytokine that regulates energy metabolism and is linked to diabetes mellitus through its metabolic actions. Leptin is angiogenic and promotes wound healing, and therefore this investigation was conducted to determine whether leptin is associated with neovascular and fibrotic complications of diabetes and other retinopathies.. Serum and vitreous samples were collected from patients classified by the presence and type of diabetic retinopathy or other ocular diseases. Leptin was measured in serum and vitreous by radioimmunoassay, and leptin and leptin receptor were localized in epiretinal membranes immunohistochemically.. Leptin levels in serum and vitreous were higher in patients with diabetes than in those without, and vitreous leptin concentrations were especially elevated in patients with proliferative diabetic retinopathy or retinal detachment. Leptin and leptin receptor were detected in fibrovascular epiretinal membrane of patients with diabetes.. Leptin in human vitreous is elevated in proliferative diabetic retinopathy, and retinal detachment and is present in fibrovascular epiretinal tissue. These data suggest an involvement of leptin in retinal disease.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Carrier Proteins; Child; Diabetic Retinopathy; Epiretinal Membrane; Female; Humans; Immunoenzyme Techniques; Leptin; Male; Middle Aged; Radioimmunoassay; Receptors, Cell Surface; Receptors, Leptin; Retinal Detachment; Vitreous Body

Preperitoneal fat is an indicator of visceral fat deposition, which is closely related to atherosclerosis and coronary heart disease in obese patients. We assessed the relationship of preperitoneal fat deposition and various clinical characteristics in 90 patients with non-insulin-dependent diabetes mellitus (NIDDM). Preperitoneal and subcutaneous fat deposition were measured by ultrasonography. In both the male and female diabetics, preperitoneal fat levels were significantly higher than in age-matched healthy subjects. We also determined blood pressures, fasting plasma glucose, glycosylated hemoglobin A1c, serum lipids, fasting immunoreactive insulin (FIRI), daily urinary C-peptide (CPR), serum leptin, urinary albumin excretion and body mass index (BMI). Of these parameters, BMI, FIRI, leptin and daily urinary CPR were positively correlated with preperitoneal fat deposition. Patients with diet therapy alone showed significantly higher preperitoneal fat levels than those receiving insulin therapy. In female, patients with increased preperitoneal fat showed higher prevalence of hypertension than those with decreased fat. Macroalbuminuric patients had a lower preperitoneal fat than microalbuminuric and normoalbuminuric patients. Patients with proliferative retinopathy exhibited lower preperitoneal fat than did those without retinopathy. Preperitoneal fat levels were positively correlated with motor or sensory nerve conduction velocity.. The present findings suggest that in NIDDM patients, increased preperitoneal fat deposition is closely associated with obesity, hypertension and hyperinsulinemia, and negatively modulates diabetic microangiopathy including nephropathy, retinopathy and neuropathy.

Topics: Adipose Tissue; Albuminuria; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Fasting; Female; Humans; Hypoglycemic Agents; Insulin; Leptin; Male; Middle Aged; Neural Conduction; Peritoneum; Proteins; Reference Values; Sensation; Skin; Time Factors; Ultrasonography

Leptin levels are elevated in end-stage renal disease, suggesting an impairment of renal leptin degradation. The present study aimed to determine whether leptin levels are also elevated in patients with earlier stages of renal disease, ie, microalbuminuric and macroalbuminuric nephropathy. A total of 60 subjects were assigned to two study groups. Group A contained 10 type 2 diabetics with macroalbuminuria, 10 type 2 diabetics with normoalbuminuria, and 10 healthy control subjects. Group B contained 10 type 2 diabetics with microalbuminuria, 10 type 2 diabetics with normoalbuminuria, and 10 healthy controls. The subgroups of both study groups were matched for sex and body fatness. In group A, macroalbuminuric diabetic patients had higher serum leptin levels than the normoalbuminuric diabetics (11.90 +/- 2.98 v 4.13 +/- 0.92 ng/mL, P < .002) and control subjects (4.78 +/- 1.37 ng/mL, P < .006). In group B, microalbuminuric diabetics had higher serum leptin levels than the normoalbuminuric diabetics (21.16 +/- 5.80 v8.74 +/- 1.89 ng/mL, P < .04) and control subjects (10.06 + 3.00 ng/mL, P < .06). In both groups A and B, creatinine clearance was inversely correlated with the serum leptin level after adjusting for body fat. In conclusion, serum leptin levels are elevated in type 2 diabetic patients with microalbuminuria and macroalbuminuria, suggesting that renal leptin degradation is already impaired in the early stages of renal disease.

Topics: Adipose Tissue; Aged; Albuminuria; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Creatinine; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Humans; Hypertension; Leptin; Male; Middle Aged; Reference Values; Triglycerides

The beta 3-Adrenergic receptor (beta 3AR) and leptin are molecules involved in the regulation of energy balance. Recently, a mutation in the beta 3AR gene (Trp64Arg) has been reported to be associated with features of insulin resistance, weight gain and early onset of Type 2 Diabetes Mellitus. The aim of this study was to determine the frequency and clinical characteristics of the Trp64Arg mutation in the beta 3AR gene in Type 2 diabetic patients, its relationship with leptin levels, and its role in microangiopathic complications.. 187 Type 2 diabetic patients and 100 unrelated non-diabetic subjects were studied. There was no difference between the diabetic and nondiabetic subjects in the frequency of the Trp64 and Arg64 alleles (92.5% vs. 92.3% and 7.5% vs. 7.7%, respectively). Type 2 diabetic patients were divided into two groups according to the presence (n = 27) or absence of the mutation (n = 160).. Mutation of the beta 3AR gene was not associated with any differences either in the clinical and metabolic parameters or microangiopathic complications. Type 2 diabetic patients carrying the Arg64 allele tended to have a lower diabetes duration, but this was not statistically significant. Plasma leptin levels were not different according to the beta 3AR genotype.. The Trp64Arg mutation is not a major determinant of Type 2 diabetes and its microangiopathic complications. Moreover, this mutation was not clinically relevant in leptin regulation.

Topics: Aged; Alleles; Blood Pressure; Body Mass Index; Case-Control Studies; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Retinopathy; Female; Humans; Leptin; Male; Middle Aged; Polymorphism, Genetic; Proteins; Receptors, Adrenergic, beta; Receptors, Adrenergic, beta-3; Receptors, Leptin; Statistics, Nonparametric