Niacin improves adiponectin secretion, glucose tolerance and insulin sensitivity in diet-induced obese rats
11
Citation
40
Reference
10
Related Paper
Citation Trend
Abstract:
The present study examined the effect of dietary niacin supplementation on fat mass, glucose control, insulin sensitivity, lipid profile, and adiponectin level in diet-induced obese rats. Male Sprague-Dawley rats (n = 21) were initially divided into 2 groups of seven and fourteen rats; the group of 14 rats was fed with a high-fat diet (HFD) and the other group of 7 rats consumed the control diet. Eight weeks after the diet regimen started, half of the rats from the HFD group were shifted to the niacin-supplemented diet (HFND; 1 mg niacin/kg diet) while the remaining rats continued on the HFD for another 6 weeks. Results obtained showed that HFD-fed obese rats exhibited significant increase in body weight gain, reduced glucose tolerance, insulin sensitivity and increased adiposity, as well as altered lipid profile after 8 weeks of feeding compared with the controls. However, niacin-supplemented rats showed reduced weight gain and body weight compared with HFD-induced obese rats even in the absence of a significant difference in the food intake among the groups in the experiment. In addition, the rats showed an improved time-course glucose control and insulin sensitivity as demonstrated by a significantly lower area under curve (AUC) values for the glucose curves. The plasma levels of cholesterol, triglycerides and low density lipoprotein (LDL) returned towards control values in rats supplemented with niacin compared with obese rats. The findings suggest that niacin exerts beneficial effect on adiposity, glucose tolerance and insulin sensitivity, and plasma lipids, and that it specifically modulates the level of serum adiponectin under obese condition.Keywords:
Niacin
Glucose tolerance test
Niacin
Cite
Citations (25)
To identify the proportion of low adiponectin level and to evaluate the role of low adiponectin level, age, body mass index, and waist circumference on the occurrence of metabolic syndrome in women with insulin resistance.The study was done by a cross-sectional survey on adult women aged 30-60 years. The study was conducted at Fatmawati Hospital-Jakarta from January to March 2008 with a total sample of 33. The sample was selected consecutively based on the presence of metabolic syndrome according to the IDF 2005 criteria. The examination of plasma adiponectin level was done by ELISA method. Insulin resistance was defined if HOMA IR > or = 2 (calculated by fasting insulin (microU/mL) x Fasting blood sugar (mmol/L) divided by 22.5). Association of low adiponectin level with insulin resistance was evaluated by calculating the Odds Ratio.Seventeen of 33 subjects with metabolic syndrome have insulin resistance, in which 7 of them (41.18%) show low adiponectin level. While in 16 subjects without insulin resistance, only one subject (6.25%) has low adiponectin level. From 8 subjects with low adiponectin level, 7 of them (87.5%) have insulin resistance. In other words, low adiponectin level is associated with increased risk of insulin resistance (Odds Ratio 10.5, P = 0.040 (CI 95% : 1.12-98.91).Low adiponectin concentration increases the risk of developing insulin resistance much more than normal adiponectin level.
Cite
Citations (12)
Niacin
Cite
Citations (33)
Polycystic ovary syndrome (PCOS) is frequently associated with insulin resistance and a consequent increased risk of metabolic diseases. The aim of the present study was to investigate the role of adiponectin in insulin resistance in PCOS women.Forty-seven patients with PCOS and 23 control subjects, matched for age and body mass index (BMI), were enrolled in the study. Clinical, metabolic and hormonal parameters and adiponectin levels were measured, and HOMA-IR score (homeostasis model assessment-insulin resistance index) was calculated for each subject.There was no difference in adiponectin levels between PCOS patients and the control group. However, adiponectin levels were negatively correlated with obesity-associated parameters and HOMA-IR score in PCOS patients and controls. As adiponectin is modulated by BMI we adjusted for BMI among the PCOS patients, and found a negative correlation between adiponectin levels and HOMA-IR score (r = -0.51, p < 0.001). Adiponectin and BMI were independent determinants of insulin resistance in PCOS patients (adjusted R2 = 0.66, p < 0.001).Adiponectin did not seem to be actively involved in the pathogenesis of PCOS. However, adiponectin levels were independently associated with insulin resistance in PCOS patients, suggesting that adiponectin might play a role in the complicated metabolic abnormalities of PCOS.
Cite
Citations (32)
Introduction: Adiponectin has been known to play an important role in the glucose and lipid metabolism, and thereby may be considered as a potential treatment target for diabetes mellitus or atherosclerotic diseases. Recently, some basic studies showed that adiponectin might not function in an insulin-resistant condition, a concept called “adiponectin resistance.” However, this concept has not been confirmed in human. Therefore, we assessed the hypothesis that the well-known inverse association between adiponectin and insulin resistance is weakened in the insulin-resistant state. Methods: We studied 2,316 middle-aged Japanese men without a medical history of cancer, cardiovascular disease, diabetes, hypertension, or dyslipidemia to determine whether or not the association between serum adiponectin levels and the insulin resistance index (HOMA-IR) differed according to insulin resistant states. Results: Mean age and body mass index of study subjects were 48±7 and 23±3, respectively. A multiple linear regression analysis revealed that log-adiponectin was inversely associated with log-HOMA-IR independently of covariates (β= − 0.235, P <0.001). Subsequently, we re-analyzed after dividing study subjects according to the tertile of HOMA-IR. As shown in the Table , the inverse association between adiponectin and HOMA-IR was considerably weakened with the escalation of insulin resistance. Specifically, adiponectin was almost positively associated with HOMA-IR in insulin-resistant subjects (β= 0.114, P =0.059). Interestingly, statistically significant associations of adiponectin with triglyceride and HDL-C were uniformly observed in all tertiles. Conclusion: The inverse association of adiponectin with insulin resistance weakened with the escalation of insulin resistance, suggesting the existence of “adiponectin resistance” in insulin-resistant individuals. This adiponectin resistance may be restricted in glucose metabolism. Table. Coefficients of adiponectin in multiple linear regression analyses with independent variables
Dyslipidemia
Cite
Citations (1)
Objective To explore the relationships between Serum levels of tumor necrosis factor-alpha TNFα,1L-6,adiponectin and insulin resistance in type 2 diabetes.Methods 80 T2DM patients and 40 healthy controls were recruited.Levels of serum TNF-α,IL-6,adiponectin,plasma glucose,insulin and BMI were measured.Insulin resistance was evaluated by HOMA-IR.Results The levels of TNF-α and IL-6 in T2DM group were significantly higher than that in control group(all P＜0.05);The levels of adiponeetin in T2DM group was significantly lower than that in control group(P＜0.05).The levels of TNF-α and IL-6 were positively correlated with HOMA-IR(P＜0.05),adiponeetin was egatively correlated nwith HOMA-IR(P＜0.01).Conclusion TNF-α,IL-6 and adiponectin were closely related with insulin resistance,and should take parts in development of T2DM.
Key words:
Diabetes mellitus,type 2; Insulin resistance; Cytokines; Adiponectin
Cite
Citations (0)
To assess insulin resistance and adiponectin profile in patients with chronic hepatitis C (CHC), according to the presence or absence of metabolic syndrome (MS).One hundred and fifty-two patients with histologically proven CHC, genotype I were prospectively studied. Parameters of MS according to the IDF criteria were evaluated. Insulin resistance was established by homeostasis model assessment (HOMA-IR]. An index > or = 2.0 was designated as IR and > or = 4 as prediabetic state. Serum adiponectin levels were measured by ELISA:MS was found in 61.48% of cases. HOMA-IR was significantly higher in patients with CHC and MS vs those without MS (7.88 +/- 1.11 vs 4.29 +/- 0.5, p=0.023]. Adiponectin levels had an inverse behaviour (9,946.1 +/- 5,811 ng/ml vs 13,215.5 +/- 815.5 ng/ml, p< 0.001]. By multiple linear regression analysis the independent predictors associated with HOMA-IR > or = 4 in patients with CHC and MS were visceral obesity, adiponectin levels, activity and degree of steatosis. Only visceral obesity and HOMA-IR were independently associated with adiponectin. A significant negative correlation was established between adiponectin and insulin (r = -0.169, p=0.003] and between adiponectin and HOMA-IR (r = -0.188, p=0.02].CHC with MS was associated with a higher insulin resistance and lower adiponectin level. Adiponectin level and insulin resistance were significantly correlated.
Steatosis
Homeostatic model assessment
Cite
Citations (35)
Adiponectin is one of the novel adipocytokines participates in the development of insulin resistance which is the common pathological basis of Type 2 Diabetes Mellitus and Metabolic Syndrome.Numerous studies have demonstrated that adiponectin is significantly correlated with the development of insulin resistance.It can ameliorate insulin sensitivity,improves glucose and lipid metabolism in vivo.The levels of adiponectin in vivo could predict the development of insulin resistance.Simultaneously,various of methods could ameliorate insulin resistance by increasing the levels of adiponectin in vivo in Traditional Chinese Medicine.Discovery of adiponectin provides a new idea for the theoretical studies and clinical preventions to insulin resistance.
Carbohydrate Metabolism
Cite
Citations (0)
Objective To investigate serum adiponectin levels in metabolic syndrome patients without diabetes and to analyse the relationship between serum adiponectin levels,and Insulin resistance(IR).Methods 92 metabolic syndrome patients without diabetes and 30 health persons were investigated. Serum adiponectin levels of all subjects were determined by using enzyme linked immunosorbent assay(ELISA).Homeostasis insulin resistance index (Homa-IR) and insulin sensitivity index(ISI) were calculated.And then,the relationship between serum adiponectin levels and Insulin resistance(IR) wil be analysed.Results 1.The serum level of adiponectin was significantly lower in metabolic syndrome without diabetes group than in normal control group (1.15±0.81mg/l,4.81±1.20 mg/1,P0.01 =).2.The serum adiponectin level was negatively correlated with Homa-IR(P0.01).and positively correlated with ISI through linear correlation analysis(P0.01).However,the serum adiponectin level was only negatively correlated with Homa-IR through multiple linear regression analysis.Conclusions The level of serum adiponectin in metabolic syndrome cases without diabetes was significantly decreased.The serum adiponectin level was negatively correlated with Homa-IR.This shows that level of serum adiponectin was correlated with metabolic syndrome and insulin resistance.
Cite
Citations (1)
Niacin has long been used as an effective lipid-altering therapy, particularly for raising HDL-C and lowering triglyceride levels. In addition, niacin modestly lowers LDL-C levels. LDL-C circulates in the blood as a heterogeneous population of various sized particles, with smaller LDL particles widely considered to be more closely associated with atherosclerosis and coronary heart disease. Recent evidence suggests that it is the total number of circulating LDL-C particles of various sizes that most closely predicts atherosclerosis risk. This review focuses on the growing body of literature suggesting that niacin favorably alters the number of circulating LDL particles of various sizes. Niacin Overview It was initially reported in 1955 that nicotinic acid (niacin) lowered cholesterol levels in normal subjects as well as in patients with hypercholesterolemia. [1] There have been many subsequent studies that have supported niacin as a broad-spectrum lipid-regulating medication. [2] Niacin reduces total cholesterol, triglycerides, VLDL-C, LDL-C and lipoprotein (a) (Lp[a]) levels, in addition to increasing HDL-C levels. [3] In its present clinical use, niacin is available in a number of formulations. Extended-release niacin (ERN) is the most widely used prescription niacin and has a better side-effect profile than the other available preparations, including dietary supplement versions of niacin. Dietary supplement niacin comes in many forms, including immediate-release or crystalline, sustained- or time-released and no-flush or flush-free formulations. Immediate-release niacin is effective and safe, even at relatively high doses (up to 12 g/day), but it has the highest incidence of flushing. Sustained-release niacin causes flushing less frequently, but it is associated with increased hepatotoxicity. Flush-free niacin is safe and well tolerated, but it has low efficacy because of limited bioavailability. [4] In an analysis of the US FDA adverse event reporting (AER) database, Alsheikh-Ali et al. described that the rate of serious AERs associated with dietary supplement formulations of niacin was 6.2-fold higher and the rate of liver toxicity was 6.7-fold higher when compared with ERN. [5] Of note, in this database, there
Niacin
B vitamins
Cite
Citations (0)