curcumin and Glucose-Intolerance

Dysglycemia is a disease state preceding the onset of diabetes and includes impaired fasting glycemia and impaired glucose tolerance. This review aimed to collect and analyze the literature reporting the results of clinical trials evaluating the effects of selected nutraceuticals on glycemia in humans. The results of the analyzed trials, generally, showed the positive effects of the nutraceuticals studied alone or in association with other supplements on fasting plasma glucose and post-prandial plasma glucose as primary outcomes, and their efficacy in improving insulin resistance as a secondary outcome. Some evidences, obtained from clinical trials, suggest a role for some nutraceuticals, and in particular Berberis, Banaba, Curcumin, and Guar gum, in the management of prediabetes and diabetes. However, contradictory results were found on the hypoglycemic effects of Morus, Ilex paraguariensis, Omega-3, Allium cepa, and Trigonella faenum graecum, whereby rigorous long-term clinical trials are needed to confirm these data. More studies are also needed for Eugenia jambolana, as well as for Ascophyllum nodosum and Fucus vesiculosus which glucose-lowering effects were observed when administered in combination, but not alone. Further trials are also needed for quercetin.

Topics: Blood Glucose; Curcumin; Diabetes Mellitus; Diabetes Mellitus, Type 2; Dietary Supplements; Glucose Intolerance; Humans; Hypoglycemic Agents; Prediabetic State; Quercetin

The objective of this systematic review was to assess available scientific data on the efficacy and safety of medicinal food plants for the treatment of impaired glucose tolerance.. We included randomized controlled trials (RCTs) with a minimum follow-up period of 6weeks. The diagnosis was determined by fasting plasma glucose values after two-hour oral glucose tolerance testing (OGTT). Two authors independently extracted data and evaluated bias. The Cochrane tool of risk of Bias Tool was used.. This review included ten trials. Most studies were highly biased as data were incomplete or reporting was selective. The two-hour fasting plasma glucose after the curcumin extract intervention showed statistical significance after 3, 6 and 9months: p<0.01. Also, glycosylated haemoglobin levels A1c (HbA1c) values after curcumin extract intervention showed statistical significance after 3, 6 and 9months: p<0.01. Insulin resistance (HOMA-IR) after curcumin extract intervention showed statistical significance after 6months and after 9months: p<0.05 and p<0.01.. Curcumin has shown the confident results to be effective for the treatment of impaired glucose tolerance. Fenugreek and flaxseed may also be effective, but due to low quality of these studies the results must be interpreted with caution.

Topics: Blood Glucose; Curcuma; Curcumin; Glucose Intolerance; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin Resistance; Phytotherapy; Plant Extracts; Plants, Medicinal; Randomized Controlled Trials as Topic

Oxidative stress is enhanced by various mechanisms. Serum oxidized low-density lipoprotein (LDL) is a useful prognostic marker in diabetic patients with coronary artery disease. To examine the effects of Theracurmin®, a highly absorbable curcumin preparation, on glucose tolerance, adipocytokines, and oxidized LDL, we conducted a double-blind placebo-controlled parallel group randomized trial in patients with impaired glucose tolerance or non-insulin-dependent diabetes mellitus. We randomly divided the patients with impaired glucose tolerance or non-insulin-dependent diabetes mellitus and stable individuals into the placebo group and the Theracurmin® (180 mg daily for 6 months) group. Of the 33 patients analyzed, 18 (14 males and 4 females) were administered placebo and 15 (9 males and 6 females) were administered Theracurmin®. The patient characteristics did not differ between the two groups. The primary endpoint, HbA1c, did not differ significantly between the two groups. However, the level of

Topics: Adiponectin; Administration, Oral; Adult; Aged; Aged, 80 and over; Antioxidants; Biomarkers; Blood Glucose; Cholesterol, LDL; Curcumin; Diabetes Mellitus, Type 2; Double-Blind Method; Female; Gastrointestinal Absorption; Glucose Intolerance; Glycated Hemoglobin; Humans; Japan; Lipoproteins, LDL; Male; Middle Aged; Time Factors; Treatment Outcome; Young Adult

Weight regain, adipose tissue growth, and insulin resistance can occur within days after the cessation of regular dieting and exercise. This phenomenon has been attributed, in part, to the actions of stress hormones as well as local and systemic inflammation. We investigated the effect of curcumin, a naturally occurring polyphenol known for its anti-inflammatory properties and inhibitory action on 11β-HSD1 activity, on preserving metabolic health and limiting adipose tissue growth following the cessation of daily exercise and caloric restriction (CR). Sprague-Dawley rats (6-7 wk old) underwent a "training" protocol of 24-h voluntary running wheel access and CR (15-20 g/day; ~50-65% of ad libitum intake) for 3 wk ("All Trained") or were sedentary and fed ad libitum ("Sed"). After 3 wk, All Trained were randomly divided into one group which was terminated immediately ("Trained"), and two detrained groups which had their wheels locked and were reintroduced to ad libitum feeding for 1 wk. The wheel locked groups received either a daily gavage of a placebo ("Detrained + Placebo") or curcumin (200 mg/kg) ("Detrained + Curcumin"). Cessation of daily CR and exercise caused an increase in body mass, as well as a 9- to 14-fold increase in epididymal, perirenal, and inguinal adipose tissue mass, all of which were attenuated by curcumin ( P < 0.05). Insulin area under the curve (AUC) during an oral glucose tolerance test, HOMA-IR, and C-reactive protein (CRP) were elevated 6-, 9-, and 2-fold, respectively, in the Detrained + Placebo group vs. the Trained group (all P < 0.05). Curcumin reduced insulin AUC, HOMA-IR, and CRP vs. the placebo group (all P < 0.05). Our results indicate that curcumin has a protective effect against weight regain and impaired metabolic control following a successful period of weight loss through diet and exercise, perhaps via inhibition of glucocorticoid action and inflammation. NEW & NOTEWORTHY Weight regain after dieting and exercise is a common phenomenon plaguing many individuals. The biological mechanisms underlying weight regain are incompletely understood and are likely multifactorial. In this paper, we examined the metabolic implications of curcumin, a compound known for its anti-inflammatory properties and inhibitory action on the enzyme 11β-HSD1, in a rodent model of adiposity rebound after the cessation of diet and exercise.

Topics: 11-beta-Hydroxysteroid Dehydrogenase Type 1; Adipose Tissue; Animals; Caloric Restriction; Corticosterone; Curcumin; Diet; Glucose Intolerance; Glucose Tolerance Test; Inflammation; Insulin Resistance; Male; Muscle, Skeletal; Obesity; Physical Conditioning, Animal; Random Allocation; Rats; Rats, Sprague-Dawley; Weight Gain

Emerging evidence suggests that high fructose consumption may be a potentially important factor responsible for the rising incidence of insulin resistance and diabetes worldwide. The present study investigated the preventive effect of curcumin on inflammation, oxidative stress and insulin resistance in high fructose fed male Wistar rats at the molecular level. Fructose feeding for 10 weeks caused oxidative stress, inflammation and insulin resistance. Curcumin treatment attenuated the insulin resistance by decreasing IRS-1 serine phosphorylation and increasing IRS-1 tyrosine phosphorylation in the skeletal muscle of high fructose fed rats. It also attenuated hyperinsulinemia, glucose intolerance and HOMA-IR level. Curcumin administration lowered tumor necrosis factor alpha (TNF-α), C reactive protein (CRP) levels and downregulated the protein expression of cyclo-oxygenase 2 (COX-2), protein kinase theta (PKCθ). In addition, inhibitor κB alpha (IκBα) degradation was prevented by curcumin supplementation. Treatment with curcumin inhibited the rise of malondialdehyde (MDA), total oxidant status (TOS) and suppressed the protein expression of extracellular kinase ½ (ERK ½), p38 in the skeletal muscle of fructose fed rats. Further, it enhanced Glutathione Peroxidase (GPx) activity in the muscle of fructose fed rats. At the molecular level, curcumin inhibited the activation of stress sensitive kinases and inflammatory cascades. Our findings conclude that curcumin attenuated glucose intolerance and insulin resistance through its antioxidant and anti-inflammatory effects. Thus, we suggest the use of curcumin as a therapeutic adjuvant in the management of diabetes, obesity and their associated complications.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Curcumin; Fructose; Glucose Intolerance; Glucose Tolerance Test; Inflammation; Insulin Resistance; Male; Oxidative Stress; Phosphorylation; Protein Serine-Threonine Kinases; Rats; Rats, Wistar; Structure-Activity Relationship

A high fat meal, frequently known as western diet (WD), exacerbates atherosclerosis and diabetes. Both these diseases are frequently associated with renal failure. Recent studies have shown that lipopolysaccharide (LPS) leaks into the circulation from the intestine in the setting of renal failure and after WD. However, it is not clear how renal function and associated disorders are affected by LPS. This study demonstrates that circulatory LPS exacerbates renal insufficiency, atherosclerosis and glucose intolerance. Renal insufficiency was induced by 2/3 nephrectomy in LDL receptor knockout mice. Nx animals were given normal diet (Nx) or WD (Nx+WD). The controls were sham operated animals on normal diet (control) and WD (WD). To verify if LPS plays a role in exaggerating renal insufficiency, polymyxin (PM), a known LPS antagonist, and curcumin (CU), a compound known to ameliorate chronic kidney disease (CKD), was given to Nx animals on western diet (Nx+WD+PM and Nx+WD+CU, respectively). Compared to control, all other groups displayed increased circulatory LPS. The Nx+WD cohort had the highest levels of LPS. Nx group had significant renal insufficiency and glucose intolerance but not atherosclerosis. WD had intense atherosclerosis and glucose intolerance but it did not show signs of renal insufficiency. Compared to other groups, Nx+WD had significantly higher cytokine expression, macrophage infiltration in the kidney, renal insufficiency, glucose intolerance and atherosclerosis. PM treatment blunted the expression of cytokines, deterioration of renal function and associated disorders, albeit not to the levels of Nx, and was significantly inferior to CU. PM is a non-absorbable antibiotic with LPS binding properties, hence its beneficial effect can only be due to its effect within the GI tract. We conclude that LPS may not cause renal insufficiency but can exaggerate kidney failure and associated disorders following renal insufficiency.

Topics: Animals; Atherosclerosis; Cholesterol; Curcumin; Diet, High-Fat; Diet, Western; Dietary Fats; Disease Models, Animal; Gene Expression; Glucose Intolerance; Hyperglycemia; Intestinal Mucosa; Intestines; Kidney; Lipopolysaccharides; Macrophages; Mice; Mice, Knockout; Nephrectomy; Polymyxins; Receptors, LDL; Renal Insufficiency

Type 2 diabetes is growing at epidemic proportions, and pharmacological interventions are being actively sought. This study examined the effect of a novel neuroprotective curcuminoid, CNB-001 [4-((1E)-2-(5-(4-hydroxy-3-methoxystyryl-)-1-phenyl-1H-pyrazoyl-3-yl)vinyl)-2-methoxy-phenol], on glucose intolerance and insulin signaling in high-fat diet (HFD)-fed mice. C57BL6 mice (5-6 weeks old) were randomly assigned to receive either a HFD (45% fat) or a low-fat diet (LFD, 10% fat) for 24 weeks, together with CNB-001 (40 mg/kg i.p. per day). Glucose tolerance test revealed that the area under the curve of postchallenge glucose concentration was elevated on HF-feeding, which was attenuated by CNB-001. CNB-001 attenuated body weight gain, serum triglycerides, and IL-6, and augmented insulin signaling [elevated phosphoprotein kinase B (p-Akt), and phosphoinsulin receptor (p-IR)β, lowered endoplasmic reticulum (ER) stress, protein-tyrosine phosphatase 1B (PTP1B)] and glucose uptake in gastrocnemius muscle of HFD-fed mice. Respiratory quotient, measured using a metabolic chamber, was elevated in HFD-fed mice, which was unaltered by CNB-001, although CNB-001 treatment resulted in higher energy expenditure. In cultured myotubes, CNB-001 reversed palmitate-induced impairment of insulin signaling and glucose uptake. Docking studies suggest a potential interaction between CNB-001 and PTP1B. Taken together, CNB-001 alleviates obesity-induced glucose intolerance and represents a potential candidate for further development as an antidiabetic agent.

Topics: Adiposity; Animals; Catalytic Domain; Cell Line; Cell Survival; Curcumin; Dietary Fats; Endoplasmic Reticulum Stress; Energy Metabolism; Fatty Liver; Glucose Intolerance; Hypoglycemic Agents; Insulin Resistance; Male; Mice, Inbred C57BL; Molecular Docking Simulation; Muscle Fibers, Skeletal; Muscle, Skeletal; Neuroprotective Agents; Obesity; Palmitic Acid; Protein Binding; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Pyrazoles; Signal Transduction; Weight Gain

Curcuma comosa Roxb. (C. comosa) is an indigenous medicinal herb that has been used in Thailand as a dietary supplement to relieve postmenopausal symptoms. Recently, a novel phytoestrogen, (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol or compound 049, has been isolated and no study thus far has investigated the role of C. comosa in preventing metabolic alterations occurring in estrogen-deprived state. The present study investigated the long-term effects (12 weeks) of C. comosa hexane extract and compound 049 on insulin resistance in prolonged estrogen-deprived rats.. Female Sprague-Dawley rats were ovariectomized (OVX) and treated with C. comosa hexane extract (125 mg, 250 mg, or 500 mg/kg body weight (BW)) and compound 049 (50 mg/kg BW) intraperitoneally three times per week for 12 weeks. Body weight, food intake, visceral fat weight, uterine weight, serum lipid profile, glucose tolerance, insulin action on skeletal muscle glucose transport activity, and GLUT-4 protein expression were determined.. Prolonged ovariectomy resulted in dyslipidemia, impaired glucose tolerance and insulin-stimulated skeletal muscle glucose transport, as compared to SHAM. Treatment with C. comosa hexane extract and compound 049, three times per week for 12 weeks, markedly reduced serum total cholesterol and low-density lipoprotein levels, improved insulin sensitivity and partially restored uterine weights in ovariectomized rats. In addition, compound 049 or high doses of C. comosa hexane extract enhanced insulin-mediated glucose uptake in skeletal muscle and increased muscle GLUT-4 protein levels.. Treatment with C. comosa and its diarylheptanoid derivative improved glucose and lipid metabolism in estrogen-deprived rats, supporting the traditional use of this natural phytoestrogen as a strategy for relieving insulin resistance and its related metabolic defects in postmenopausal women.

Topics: Animals; Biological Transport; Cholesterol; Cholesterol, LDL; Curcuma; Diarylheptanoids; Dyslipidemias; Estrogens; Female; Glucose; Glucose Intolerance; Glucose Transporter Type 4; Heptanol; Insulin; Insulin Resistance; Muscle, Skeletal; Organ Size; Ovariectomy; Phytoestrogens; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Uterus