Insulin Resistance In Type 2 Diabetes Mellitus Patients Research Articles

Relationship between serum 1, 5-anhydroglucitol level and insulin resistance, microvascular complications in type 2 diabetes mellitus

Objective: To explore the relationship between serum 1, 5-dehydratoglucitol (1, 5-AG) level and insulin resistance, microvascular complications in patients with type 2 diabetes mellitus (T2DM). Methods: The clinical data of 836 patients with T2DM admitted to the Changsha Central Hospital Affiliated to University of South China from May to December 2023 were retrospectively and cross-sectionally analyzed. Serum 1, 5-AG levels were detected by pyranose oxidase method. According to the microvascular complications (diabetic peripheral neuropathy, diabetic nephropathy, diabetic retinopathy), the patients were divided into simple group (no microvascular complications, n=490), complication group 1 (1 microvascular complications, n=217), and complication group 2 (2 or more microvascular complications, n=129). The relationship between serum 1, 5-AG level and the related indicators of insulin resistance in T2DM patients were explored by Spearman correlation analysis, and the influencing factors of microvascular complications in T2DM patients were explored by multiple ordered logistic regression analysis. Results: The levels of FBG(fasting blood glucose) [(7.37±0.56) mmol/L], FINS(fasting insulin) [(11.34±1.86) mU/L] and HOMA-IR(homeostatic model assessment of insulin resistance) (0.96±0.31) in simple group were lower than those in complication group 1 [(8.37±1.02) mmol/L, (16.26±2.32) mU/L, (1.32±0.41)], complication group 2 [(10.25±2.13) mmol/L, (18.53±2.67) mU/L, (1.54±0.44)], and FBG, FINS and HOMA-IR in complication group 1 were lower than those in complication group 2, and the differences were statistically significant (F=537.470, 791.690, 136.340, P<0.001). Serum 1, 5-AG level in simple group [77.16 (16.30, 128.07) μg/ml] was higher than that in complication group 1 [51.05 (14.67, 63.18) μg/ml] and complication group 2 [30.42 (12.53, 47.26) μg/ml], and the serum level of 1, 5-AG in complication group 1 was higher than that in complication group 2, and the difference was statistically significant (H=210.020, P<0.001). The results of Spearman correlation analysis showed that serum 1, 5-AG level was negatively correlated with FBG, FINS and HOMA-IR in T2DM patients (r=-0.431, -0.372, -0.546, P<0.001). The results of multiple ordered logistic regression analysis showed that Longer duration of diabetes (OR=2.261, 95%CI: 1.564-3.269), increased HbA1c (OR=2.040, 95%CI: 1.456-2.858), and increased HOMA-IR (OR=2.158, 95%CI: 1.484-3.137) and decreased 1, 5-AG (OR=2.512, 95%CI: 1.691-3.732) were independent risk factors for microvascular complications in T2DM patients (P<0.05). The results of ROC curve analysis showed that the area under the curve of serum 1, 5-AG in the identification of one microvascular complication was 0.763 (95%CI: 0.731-0.795), and the area under the curve of serum 1, 5-AG in the identification of two or more microvascular complications was 0.730 (95%CI: 0.692-0.767). Conclusion: Serum 1, 5-AG level is negatively correlated with insulin resistance in T2DM patients. Low serum 1, 5-AG level may be an independent risk factor for microvascular complications in T2DM patients.

Correlation Between Serum Vitamin E and HOMA-IR in Patients with T2DM.

Peroxidation is one of the important causes of insulin resistance (IR), and vitamin E is a natural antioxidant, and there may be some correlation between serum vitamin E levels and insulin resistance. The correlation between serum vitamin E and insulin resistance in type 2 diabetes mellitus (T2DM) population. Two hundred and forty-two people (119 with T2DM) were included. One hundred and nineteen patients with T2DM were selected as the case group, and 123 people with non-T2DM were selected as the control group. People insulin resistance was detected by the homeostasis model assessment method (HOMA-IR) greater than 2.69 were included in the diabetic insulin resistance group, and those with HOMA-IR less than 2.69 were included in the diabetic non-insulin resistance group. Record the general body indicators, biochemical indicators, hepatic function indicators, vitamin E, and other indicators. Correlation analysis, logistic regression, trend analysis, and restricted cubic spline (RCS) were performed using SPSS 25.0 and R 4.1.1 software. Correlation analysis, logistic regression, trend analysis, restricted cubic spline (RCS) analysis were conducted on general body indicators, biochemical indicators, hepatic function indicators, vitamin E, and other indicators. The logistic regression results showed that after adjusting for confounding factors, vitamin E was an independent influencing factor for insulin resistance in T2DM patients (P < 0.001). The trend analysis results show that with the decrease of serum vitamin E levels, the risk of insulin resistance in T2DM patients gradually increases. The RCS results showed that the risk of insulin resistance was significantly increased when the serum vitamin E level was lower than 10,575.23 ng/mL. Serum vitamin E levels are lower in T2DM patients than in healthy populations; Vitamin E is an independent influencing factor for HOMA-IR in T2DM patients. The risk of insulin resistance gradually increases in T2DM patients as serum vitamin E levels decrease. Vitamin E is a risk factor for insulin resistance at serum vitamin E levels below 10,575.23 ng/mL. At higher serum vitamin E levels than 10,575.23 ng/mL, vitamin E is a protective factor for insulin resistance.

Effects of vitamin D supplementation on glucose and lipid metabolism in patients with type 2 diabetes mellitus and risk factors for insulin resistance.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease featured by insulin resistance (IR) and decreased insulin secretion. Currently, vitamin D deficiency is found in most patients with T2DM, but the relationship between vitamin D and IR in T2DM patients requires further investigation. To explore the risk factors of IR and the effects of vitamin D supplementation on glucose and lipid metabolism in patients with T2DM. Clinical data of 162 T2DM patients treated in First Affiliated Hospital of Harbin Medical University between January 2019 and February 2022 were retrospectively analyzed. Based on the diagnostic criteria of IR, the patients were divided into a resistance group (n = 100) and a non-resistance group (n = 62). Subsequently, patients in the resistance group were subdivided to a conventional group (n = 44) or a joint group (n = 56) according to the treatment regimens. Logistic regression was carried out to analyze the risk factors of IR in T2DM patients. The changes in glucose and lipid metabolism indexes in T2DM patients with vitamin D deficiency were evaluated after the treatment. Notable differences were observed in age and body mass index (BMI) between the resistance group and the non-resistance group (both P < 0.05). The resistance group exhibited a lower 25-hydroxyvitamin D3 (25(OH)D3) level, as well as notably higher levels of 2-h postprandial blood glucose (2hPG), fasting blood glucose (FBG), and glycosylated hemoglobin (HbA1c) than the non-resistance group (all P < 0.0001). Additionally, the resistance group demonstrated a higher triglyceride (TG) level but a lower high-density lipoprotein-cholesterol (HDL-C) level than the non-resistance group (all P < 0.0001). The BMI, TG, HDL-C, 25(OH)D3, 2hPG, and HbA1c were found to be risk factors of IR. Moreover, the post-treatment changes in levels of 25(OH)D3, 2hPG, FBG and HbA1c, as well as TG, total cholesterol, and HDL-C in the joint group were more significant than those in the conventional group (all P < 0.05). Patients with IR exhibit significant abnormalities in glucose and lipid metabolism parameters compared to the non-insulin resistant group. Logistic regression analysis revealed that 25(OH)D3 is an independent risk factor influencing IR. Supplementation of vitamin D has been shown to improve glucose and lipid metabolism in patients with IR and T2DM.

Clinical potential and mechanistic insights of mulberry (Morus alba L.) leaves in managing type 2 diabetes mellitus: Focusing on gut microbiota, inflammation, and metabolism.

Natural herbs are gradually gaining recognition for their efficacy and safety in preventing diabetes and improving quality of life. Morus alba L. is a plant widely grown in Asia and is a traditional Chinese herb with a long history of use. Furthermore, several parts of Morus alba L. have been found to have significant health benefits. In particular, mulberry (Morus alba L.) leaves (ML) have been shown in human and animal studies to be promising hypoglycemic agents that can reduce or prevent glucolipid metabolism disorders caused by imbalances in the gut microbiota, inflammation, and oxidative stress and have demonstrated significant improvements in glucose metabolism-related markers, effectively lowering blood glucose, and reducing hyperglycemia-induced target organ damage. This review briefly summarizes the methods for obtaining ML's bioactive components, elaborates on the clinical potential of the relevant components in managing type 2 diabetes mellitus (T2DM), and focuses on the therapeutic mechanisms of gut microbiota, inflammation, oxidative stress, and metabolism, to provide more inspiration and directions for future research in the field of traditional natural plants for the management of T2DM and its complications. Research on ML and its bioactive components was mainly performed using electronic databases, including PubMed, Google Scholar, and ScienceNet, to ensure the review's quality. In addition, master's and doctoral theses and ancient documents were consulted. In clinical studies, we found that ML could effectively reduce blood glucose, glycated hemoglobin, and homeostasis model assessment of insulin resistance in T2DM patients. Furthermore, many in vitro and in vivo experiments have found that ML is involved in various pathways that regulate glucolipid metabolism and resist diabetes while alleviating liver and kidney damage. As a potential natural anti-diabetic phytomedicine, an in-depth study of ML can provide new ideas and valuable references for applying traditional Chinese medicine to treat T2DM. While continuously exploring its clinical efficacy and therapeutic mechanism, the extraction method should be optimized to improve the efficacy of the bioactive components. in addition, further research on the dose-response relationship of drugs to determine the effective dose range is required.

Evaluating the role of homoeopathically potentised magnesium sulphate 30C on insulin resistance in type 2 diabetes mellitus patients in surat, India: A randomised controlled crossover clinical trial

The World Health Organization has declared type 2 diabetes mellitus (T2DM) to have reached pandemic proportions. The affected population worldwide has increased from 108 million in 1980 to 537 million in 2021. Recent studies have shown that T2DM is often associated with altered magnesium levels. The study aimed to assess the effects of homoeopathically potentised Magnesium sulphate 30C on insulin resistance in T2DM patients in Surat, India. The study design was a randomised controlled crossover trial conducted at the ZFR Multi-specialty Homoeopathy Clinic, Surat, India. A total of 79 participants were divided randomly into two groups. One group received the placebo and the other received the potentised Magnesium sulphate 30C in the first period (12 weeks). This was followed by a washout period and the groups were crossed over to receive the other intervention, again for 12 weeks. The analysis of variance was used to find the comparisons between both groups for the mean value of glycosylated haemoglobin (HbA1c), fasting blood sugar (FBS), fasting insulin, serum magnesium, homeostatic model assessment for insulin resistance (HOMA-IR), and estimated average glucose levels. HbA1c (%) (p&lt;0.001) showed a significant difference between both groups.

Combined effects of vitamin D supplementation and endurance exercise training on insulin resistance in newly diagnosed type 2 diabetes mellitus patients with vitamin D deficiency: study protocol for a randomized controlled trial

BackgroundAlthough approximately 50% of Chinese with type 2 diabetes mellitus (T2DM) patients have vitamin D deficiency, studies regarding vitamin D supplementation on insulin resistance (IR) have mainly focused on non-Asians. Endurance exercise training (ET) enhances insulin-mediated glucose metabolism, which plays a critical role in T2DM prevention and control. However, the combined effects of vitamin D supplementation and ET on IR in T2DM patients are unclear. The objectives of this study is to investigate the synergistic effect of vitamin D supplementation combined with exercise training intervention on IR in T2DM patients.Methods and analysisWe propose a 3-month randomized controlled trial among 60 T2DM patients aged 40–65, newly diagnosed with T2DM ≤ 1 year, and with stable HbA1c level (≤ 8.0%) in the past 3 months. The participants will be randomly allocated to the vitamin D group, vitamin D combined with exercise training group, exercise training group, and control group (CG) using a computer-generated random number sequence. At baseline, participants will undergo a medical review, anthropometric measurements, dual X-ray absorptiometry, a 75-g oral glucose tolerance test (OGTT), ankle-brachial index measurements, and physical fitness measurements and will complete related lifestyle questionnaires. Fasting blood lipid and glucose levels were also measured. In a 3-month intervention period, vitamin D intervention group will receive a dose of 1000 IU daily; exercise group will perform a 1-h endurance exercise 3 times per week (maximal heart rate, 60–80%), and the control group will receive apparently identical tablets. Additionally, all participants will be advised to maintain their normal diet and physical activities during the intervention. All measurements will be repeated at 3-month follow-up after the intervention with the primary outcome measure expressed as a change from baseline in insulin sensitivity and secretion. Secondary outcome measures will compare the changes in anthropometry, ankle-brachial index, and physical fitness factors (e.g., peak oxygen uptake, hand grip strength). Data will be managed and analyzed using the Statistical Package for the Social Sciences.DiscussionThis is the first study to conduct a randomized trial to clearly determine the independent and combined effects of vitamin D supplementation and endurance exercise trial on IR in Chinese T2DM patients as measured by OGTT. The findings from the proposed study will not only provide new evidences that vitamin D supplementation plays an important role in IR management but also develop a simple and efficient method to improve IR-associated metabolic diseases for T2DM patients.Trial registrationChinese Clinical Trial Registry ChiCTR1800015383, Registered on 28 March 2018

Insulin Therapy Is Associated With an Increased Risk of Carotid Plaque in Type 2 Diabetes: A Real-World Study.

Background: Controversies concerning the association between insulin therapy and atherosclerotic lesions in type 2 diabetes mellitus (T2DM) remain to exist. The purpose of this study was to investigate whether insulin therapy in T2DM patients is linked with the increased risk of carotid atherosclerosis in real-world settings.Methods: We retrospectively enrolled 2,356 hospitalized patients with T2DM, including 1,716 subjects receiving insulin therapy and 640 subjects without receiving insulin therapy. Carotid atherosclerotic lesions including carotid intima-media thickness (CIMT), carotid plaque and carotid stenosis were assessed by Doppler ultrasonography and were compared between T2DM patients treated with and without insulin.Results: After adjusting for age and duration of diabetes, there was a significant increase in the prevalence of carotid plaque in both men (52.0 vs. 41.7%, p = 0.007) and women (49.6 vs. 39.7%, p = 0.003) receiving insulin therapy than in those without receiving insulin therapy. After further controlling for other confounding factors, compared with the patients without receiving insulin therapy, the risk of carotid plaque was still significantly increased not only in women treated with insulin (OR: 1.810; 95% CI: 1.155–2.837, p = 0.010), but also in men treated with insulin (OR: 1.867; 95% CI: 1.307–2.666; p = 0.001). Additionally, HOMA2-B% was higher in both women and men without receiving insulin therapy compared with those receiving insulin therapy (p < 0.001 in both men and women), but HOMA-IR was significantly higher in patients treated with insulin than in those without receiving insulin therapy (p < 0.001 in both men and women).Conclusions: Insulin therapy is associated with markedly increased risk of carotid atherosclerotic lesions in type 2 diabetes, which partly attribute to the more serious insulin resistance in T2DM patients receiving insulin therapy.

Effect of self surrender practice on insulin resistance in individuals withtype 2 diabetes mellitus without depression: asingle-blinded randomized controlled trial

Self surrender practice (latihanpasrahdiri/LPD) is a form of relaxation therapy that has been increasingly used, not only in the treatment of psychosomatic diseases, but also of other non-psychosomatic diseases. Previous studies reported thatSSP shows modest improvement on clinical parameters of type 2diabetes mellitus(T2DM) patients,not onlydepression symptoms improvement, but also glycemic control.However, the effect of LPD on insulin resistance has not been investigated. The study aimed to investigate the effect of LPD on insulin resistance in T2DM patients without depression. This was a single-blinded, randomized, controlledtrial conducted in outpatient unit of the Department of Internal Medicine, Dr. Soeradji Tirtonegoro General Hospital, Klaten, Central Java.The subjects of the study were T2DM patients aged over 30 yearsand had no depression.Fourthy-four T2DM patients were randomized into two groups as the controlgroup and the treatment group who underwent SSP group for eight weeks. The data of insulin resistancemeasured by HOMA-IR, perceived stress scale (PSS), fasting plasma glucose (FBG), HbA1c, and two hour plasma glucose (PPG)levels of both groups werecollected and statistically analysed.No significantly different in the patient’scharacteristics of both groups was observed.At the end of the study period, the LPD group showed reduction of HOMA-IR and HbA1c but not statistically significant, (ΔHOMA-IR = -0.39±1.52; p = 0.976; HbA1c=-0.55±0.85%; p = 0.189). The FBG and PPGincreased in the LPD group compared to control but also not statistically significant (ΔFBG=10.16±50.33; p=0.294; PPG=40.74±69.35; p=0.062). We also observed the decrease of stress level in LPD group compared to control groupbut it was no statistical significance (ΔPSS=-5.09±6.47; p=0.655).Self surrender practice (LPD) decreasesHOMA-IR, improves glycemic control (HbA1c) and reduces stress levels in T2DM patients without depressionAlthough the theyarenot statisticallysignificant, however they may be clinically significant.

Skeletal Muscle Lipid Droplets and the Athlete's Paradox.

The lipid droplet (LD) is an organelle enveloped by a monolayer phospholipid membrane with a core of neutral lipids, which is conserved from bacteria to humans. The available evidence suggests that the LD is essential to maintaining lipid homeostasis in almost all organisms. As a consequence, LDs also play an important role in pathological metabolic processes involving the ectopic storage of neutral lipids, including type 2 diabetes mellitus (T2DM), atherosclerosis, steatosis, and obesity. The degree of insulin resistance in T2DM patients is positively correlated with the size of skeletal muscle LDs. Aerobic exercise can reduce the occurrence and development of various metabolic diseases. However, trained athletes accumulate lipids in their skeletal muscle, and LD size in their muscle tissue is positively correlated with insulin sensitivity. This phenomenon is called the athlete’s paradox. This review will summarize previous studies on the relationship between LDs in skeletal muscle and metabolic diseases and will discuss the paradox at the level of LDs.

Alterations in effective connectivity within the Papez circuit are correlated with insulin resistance in T2DM patients without mild cognitive impairment.

Insulin resistance (IR) can significantly affect the hippocampus, a component of a larger memory circuit called the Papez circuit. This study was performed to identify altered effective connectivity within the Papez circuit in type 2 diabetes mellitus (T2DM) patients without mild cognitive impairment (MCI) and to determine the relationships between these alterations and IR. T2DM patients without MCI (n = 105) and age-, sex-, and education-matched healthy controls (n = 106) were included in this study. Granger causality analysis (GCA) with seed regions in the hippocampus was performed to identify abnormal effective connectivity in the brains of T2DM patients without MCI. Furthermore, correlation analysis was conducted to detect the association between aberrant effective connectivity and IR in T2DM patients without MCI. Compared to healthy controls, T2DM patients without MCI demonstrated abnormal directional connectivity both to and from the hippocampus; the main abnormalities were located in several brain areas, including the cingulate cortex, amygdala, and prefrontal cortex, all of which are components of the Papez circuit. This altered effective connectivity network in the Papez circuit was correlated with IR in T2DM patients without MCI. Effective connectivity network alterations within the Papez circuit occurred prior to the appearance of mild cognitive deficits in T2DM patients and were correlated with IR. The current study may improve our understanding of the IR-related neurological mechanisms involved in T2DM.

Insulin Resistance the Link between T2DM and CVD: Basic Mechanisms and Clinical Implications.

Insulin resistance (IR) is a cardinal feature of type 2 diabetes mellitus (T2DM). It also is associated with multiple metabolic abnormalities which are known cardiovascular disease (CVD) risk factors. Thus, IR not only contributes to the development of hyperglycemia in T2DM patients, but also to the elevated CVD risk. Improving insulin sensitivity is anticipated to both lower the plasma glucose concentration and decrease CVD risk in T2DM patients, independent of glucose control. We review the molecular mechanisms and metabolic consequences of IR in T2DM patients and discuss the importance of addressing IR in the management of T2DM.

IRS-1 genetic polymorphism (r.2963G>A) in type 2 diabetes mellitus patients associated with insulin resistance.

BackgroundInsulin receptor substrate (IRS) molecules are key mediators in insulin signaling. Several polymorphisms in the IRS genes have been identified, but only the Gly to Arg 972 substitution of IRS-1 seems to have a pathogenic role in the development of type 2 diabetes mellitus (T2DM). Many polymorphisms described in IRS-1 gene, especially Gly972Arg substitution, are shown to be associated with insulin resistance (IR) in T2DM.Subjects and methodsThis prospective case–control study was performed during the period from November 2014 to May 2015. All patients were selected from the Department of Internal Medicine and were screened for eligibility for this study. Subjects were divided into two groups: first group consisted of 100 T2DM patients; second group consisted of 120 nondiabetic controls. First group was further divided into two subgroups: 66 IR patients and 34 insulin-sensitive (IS) patients (homeostatic model assessment [HOMA] was performed). Restriction fragment length polymorphism (RFLP) was performed using specific primers for scanning single-nucleotide polymorphisms (SNPs) such as Gly972Arg (rs1801278 SNP).ResultsTaking GG genotype and G allele as references, GA, GA+AA genotypes and A allele showed significantly higher frequency in the T2DM group when compared to the control group, with higher risk to develop T2DM in healthy controls. Taking GG as a reference, rs1801278GA+AA genotype and A allele showed significantly higher proportion in IR when compared to IS, with higher risk to develop IR in T2DM patients. Logistic regression analysis showed that higher FBG, fasting plasma insulin (FPI), HOMA-IR, GA+AA genotypes were associated with higher risk to develop IR in univariable analysis.ConclusionIRS-1 genetic factor may be a significant genetic determinant for IR in T2DM patients during severe/acute-phase hyperglycemia.

Pioglitazone inhibits mitochondrial pyruvate metabolism and glucose production in hepatocytes.

Pioglitazone is used globally for the treatment of type 2 diabetes mellitus (T2DM) and is one of the most effective therapies for improving glucose homeostasis and insulin resistance in T2DM patients. However, its mechanism of action in the tissues and pathways that regulate glucose metabolism are incompletely defined. Here we investigated the direct effects of pioglitazone on hepatocellular pyruvate metabolism and the dependency of these observations on the purported regulators of mitochondrial pyruvate transport, MPC1 and MPC2. In cultured H4IIE hepatocytes, pioglitazone inhibited [2-14 C]-pyruvate oxidation and pyruvate-driven oxygen consumption and, in mitochondria isolated from both hepatocytes and human skeletal muscle, pioglitazone selectively and dose-dependently inhibited pyruvate-driven ATP synthesis. Pioglitazone also suppressed hepatocellular glucose production (HGP), without influencing the mRNA expression of key HGP regulatory genes. Targeted siRNA silencing of MPC1 and 2 caused a modest inhibition of pyruvate oxidation and pyruvate-driven ATP synthesis, but did not alter pyruvate-driven HGP and, importantly, it did not influence the actions of pioglitazone on either pathway. In summary, these findings outline a novel mode of action of pioglitazone relevant to the pathogenesis of T2DM and suggest that targeting pyruvate metabolism may lead to the development of effective new T2DM therapies.

A Prospective Cohort Study on IRS Gene Polymorphisms in Type 2 Diabetes Mellitus Patients during Severe/Acute Hyperglycemia Phase 1: Association with Insulin Resistance

Purpose: To investigate the genetic polymorphisms that may contribute to the worsening of insulin resistance in type 2 diabetes mellitus (T2DM) with severe or acute hyperglycemia.Methods: This is a prospective cohort study involving 156 T2DM patients with severe or acute hyperglycemia from all medical wards of the National University of Malaysia Medical Centre (UKMMC) that were placed on insulin therapy. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to determine the genetic association of insulin receptor substrate (IRS) gene with insulin resistance. Insulin resistance status was determined using the homeostatic model assessment for insulin resistance (HOMA-IR) index.Results: IRS1 polymorphisms were associated with increased insulin resistance (X2 = 5.09, p = 0.023) in T2DM patients with severe/acute hyperglycemia. IRS2 polymorphisms were not associated with insulin resistance (X2 = 0.69, p = 0.406) in this group of patients.Conclusion: IRS1 genetic factor alone may be a significant genetic determinant for insulin resistance in T2DM patients during severe/acute phase hyperglycemia.Keywords: Insulin receptor substrate, Genetic, Polymorphism, Diabetes, Insulin resistance, Hyperglycemia, IRS1, IRS2

Serum Preadipocyte Factor-1 Concentrations in Females with Obesity and Type 2 Diabetes Mellitus: The Influence of Very Low Calorie Diet, Acute Hyperinsulinemia, and Fenofibrate Treatment

Appropriate differentiation capacity of adipose tissue significantly affects its ability to store lipids and to protect nonadipose tissues against lipid spillover and development of insulin resistance. Preadipocyte factor-1 (Pref-1) is an important negative regulator of preadipocyte differentiation. The aim of our study was to explore the changes in circulating Pref-1 concentrations in female subjects with obesity (OB) (n=19), females with obesity and type 2 diabetes mellitus (T2DM) (n=22), and sex- and age-matched healthy control subjects (C) (n=22), and to study its modulation by very low calorie diet (VLCD), acute hyperinsulinemia during isoglycemic-hyperinsulinemic clamp, and 3 months' treatment with PPAR-α agonist fenofibrate. At baseline, serum Pref-1 concentrations were significantly higher in patients with T2DM compared to control group, while only nonsignificant trend towards higher levels was observed in OB group. 3 weeks of VLCD decreased Pref-1 levels in both OB and T2DM group, whereas 3 months of fenofibrate treatment had no significant effect. Hyperinsulinemia during the clamp significantly suppressed Pref-1 levels in both C and T2DM subjects and this suppression was unaffected by fenofibrate treatment. In a combined population of all groups, circulating Pref-1 levels correlated positively with insulin, leptin and glucose levels and HOMA (homeostasis model assessment) index. We conclude that elevated Pref-1 concentrations in T2DM subjects may contribute to impaired adipose tissue differentiation capacity associated with insulin resistance in obese patients with T2DM. The decrease of Pref-1 levels after VLCD may be involved in the improvement of metabolic status and the amelioration of insulin resistance in T2DM patients.

Clinical study on the effect of puerarin on insulin resistance in patients with type 2 diabetes mellitus

Objective To evaluate the effect of puerarin on insulin resistance (IR)in type 2 diabetes mellitus(T2DM).Methods Fifty T2DM patients were selected and treated with puerarin and 30 healthy volunteers were selected as control group.The blood glucose and insulin levels were measured,and insulin sensitivity index was calculated before and after treatment.Results After the treatment for 2 weeks,the serum insulin levels were decreased significantly in T2DM patients after treatment (P＜0.05 ).Conclusion The puerarin has good effects on T2DM.It may decrease the serum insulin levels and improve insulin resistance in T2DM patients significantly. Key words: Type 2 diabetes mellitus; Prerarin; Insulin resistance