Dajin Zou

Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine.

CONTEXT Berberine, a natural plant alkaloid, is usually used as an antibiotic drug. The potential glucose-lowering effect of berberine was noted when it was used for diarrhea in diabetic patients. In vitro and in vivo studies have then showed its effects on hyperglycemia and dyslipidemia. OBJECTIVE The objective of the study was to evaluate the efficacy and safety of berberine in the treatment of type 2 diabetic patients with dyslipidemia. DESIGN One hundred sixteen patients with type 2 diabetes and dyslipidemia were randomly allocated to receive berberine (1.0 g daily) and the placebo for 3 months. The primary outcomes were changes in plasma glucose and serum lipid concentrations. Glucose disposal rate (GDR) was measured using a hyperinsulinemic euglycemic clamp to assess insulin sensitivity. RESULTS In the berberine group, fasting and postload plasma glucose decreased from 7.0 +/- 0.8 to 5.6 +/- 0.9 and from 12.0 +/- 2.7 to 8.9 +/- 2.8 mm/liter, HbA1c from 7.5 +/- 1.0% to 6.6 +/- 0.7%, triglyceride from 2.51 +/- 2.04 to 1.61 +/- 1.10 mm/liter, total cholesterol from 5.31 +/- 0.98 to 4.35 +/- 0.96 mm/liter, and low-density lipoprotein-cholesterol from 3.23 +/- 0.81 to 2.55 +/- 0.77 mm/liter, with all parameters differing from placebo significantly (P < 0.0001, P < 0.0001, P < 0.0001, P = 0.001, P < 0.0001, and P <0.0001, respectively). The glucose disposal rate was increased after berberine treatment (P = 0.037), although no significant change was found between berberine and placebo groups (P = 0.063). Mild to moderate constipation was observed in five participants in the berberine group. CONCLUSIONS Berberine is effective and safe in the treatment of type 2 diabetes and dyslipidemia.

Effects of Metformin Versus Glipizide on Cardiovascular Outcomes in Patients With Type 2 Diabetes and Coronary Artery Disease

OBJECTIVE The two major classes of antidiabetic drugs, sulfonylureas and metformin, may differentially affect macrovascular complications and mortality in diabetic patients. We compared the long-term effects of glipizide and metformin on the major cardiovascular events in type 2 diabetic patients who had a history of coronary artery disease (CAD). RESEARCH DESIGN AND METHODS This study is a multicenter, randomized, double-blind, placebo-controlled clinical trial. A total of 304 type 2 diabetic patients with CAD, mean age = 63.3 years (range, 36–80 years), were enrolled. Participants were randomly assigned to receive either glipizide (30 mg daily) or metformin (1.5 g daily) for 3 years. The primary end points were times to the composite of recurrent cardiovascular events, including death from a cardiovascular cause, death from any cause, nonfatal myocardial infarction, nonfatal stroke, or arterial revascularization. RESULTS At the end of study drug administration, both groups achieved a significant decrease in the level of glycated hemoglobin (7.1% in the glipizide group and 7.0% in the metformin group). At a median follow-up of 5.0 years, 91 participants had developed 103 primary end points. Intention-to-treat analysis showed an adjusted hazard ratio (HR) of 0.54 (95% CI 0.30–0.90; P = 0.026) for the composites of cardiovascular events among the patients that received metformin, compared with glipizide. The secondary end points and adverse events were not significantly different between the two groups. CONCLUSIONS Treatment with metformin for 3 years substantially reduced major cardiovascular events in a median follow-up of 5.0 years compared with glipizide. Our results indicated a potential benefit of metformin therapy on cardiovascular outcomes in high-risk patients.

Glycemic control among patients in China with type 2 diabetes mellitus receiving oral drugs or injectables

BackgroundThe prevalence of type 2 diabetes mellitus (T2DM) is increasing rapidly among Chinese adults, and limited data are available on T2DM management and the status of glycemic control in China. We assessed the efficacy of oral antidiabetes drugs (OADs), glucagon-like peptide-1 (GLP-1) receptor agonists, and insulin for treatment of T2DM across multiple regions in China.MethodsThis was a multicenter, cross-sectional survey of outpatients conducted in 606 hospitals across China. Data from all the patients were collected between April and June, 2011.ResultsA total of 238,639 patients were included in the survey. Eligible patients were treated with either OADs alone (n=157,212 [65.88%]), OADs plus insulin (n=80,973 [33.93%]), or OADs plus GLP-1 receptor agonists (n=454 [0.19%]). The OAD monotherapy, OAD + insulin, and OAD + GLP-1 receptor agonist groups had mean glycosylated hemoglobin (HbA1c) levels (±SD) of 7.67% (±1.58%), 8.21% (±1.91%), and 7.80% (±1.76%), respectively. Among those three groups, 34.63%, 26.21%, and 36.12% met the goal of HbA1c <7.0%, respectively. Mean HbA1c and achievement of A1c <7.0% was related to the duration of T2DM.ConclusionsLess than one third of the patients had achieved the goal of HbA1c <7.0%. Glycemic control decreased and insulin use increased with the duration of diabetes.

Standards of care for type 2 diabetes in China

Department of Endocrinology and Metabolism, Guangdong Provincial Key Laboratory of Diabetology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China Department of Endocrinology, Peking University People’s Hospital, Beijing, China Shanghai Diabetes Institute, Shanghai Clinical Center for Diabetes, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China Department of Endocrinology, Chinese People’s Liberation Army General Hospital, Beijing, China Institute of Metabolism and Endocrinology, Key Laboratory of Diabetes Immunology, Ministry of Education, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital and the Diabetes Center, Central South University, Changsha, China Department of Endocrinology, Changhai Hospital, Second Military Medical University, Shanghai, China Department of Endocrinology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China Tianjin Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China Department of Endocrinology, Qilu Hospital of Shandong University, Ji’nan, China Department of Endocrinology, Beijing Hospital, Beijing, China Department of Endocrinology, Peking University First Hospital, Beijing, China Department of Endocrinology, Xijing Hospital, Fourth Military Medical University, Xi’an, China Department of Endocrinology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China Department of Endocrinology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China Department of Endocrinology, Gansu Provincial Hospital, Lanzhou, China Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China Department of Endocrinology, The First Hospital of China Medical University, Shenyang, China Department of Endocrinology, Affiliated Hospital of Guiyang Medical University, Guiyang, China Department of Endocrinology, Hebei General Hospital, Shijiazhuang, China Department of Endocrinology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China Department of Endocrinology, Heilongjiang Provincial Hospital, Harbin, China Department of Endocrinology, China Japan Friendship Hospital, Beijing, China

Rosiglitazone protects against palmitate-induced pancreatic beta-cell death by activation of autophagy via 5′-AMP-activated protein kinase modulation

Promoting beta-cell survival is crucial for the prevention of beta-cell failure in diabetes. Thiazolidinediones, a widely used drug to improve insulin sensitivity in clinical practice, is found to have a protective effect on islet beta-cell. To date, the mechanism underlying the protective role of thiazolidinedione on beta-cell survival remain largely unknown. Activation of autophagy was detected by transmission electron microscopy, western blot, and GFP-LC3 transfection. Cell viability was examined by WST-8. Cell apoptosis was demonstrated by DAPI and Annexin V/PI staining. Colony formation assay was used to detect long-term cell viability. We demonstrated that rosiglitazone-treated beta-cells were more resistant to palmitate-induced apoptosis. The conversion of LC3-I to LC3-II and accumulated autophagosomes were found to be upregulated in rosiglitazone-treated cells. Inhibition of autophagy augmented palmitate-induced apoptosis with rosiglitazone treatment, suggesting that autophagy plays an important role in the survival function of rosiglitazone on beta-cells. Furthermore, we showed that rosiglitazone could induce AMP-activated protein kinase (AMPK) phosphorylation and reduce p70S6 kinase phosphorylation. Inhibition of AMPK impaired autophagy activation and enhanced palmitate-induced apoptosis during rosiglitazone treatment. These findings reveal that rosiglitazone-induced autophagy contributes to its protective function on beta-cells during palmitate treatment.

Liraglutide protects pancreatic β-cells against free fatty acids in vitro and affects glucolipid metabolism in apolipoprotein E‑/‑ mice by activating autophagy

The aim of the present study was to determine whether liraglutide (LRG), a long acting glucagon-like peptide 1 analogue, exerted a protective effect on free fatty acid (FFA)-treated pancreatic β-cells via activating autophagy. INS-1 insulinoma pancreatic islet cell lines were treated with FFA and the levels of cell necrosis, apoptosis and autophagy were detected using an MTT assay, flow cytometry and electron microscopy (ECM). A type 2 diabetes mellitus mouse model was established through treatment of mice with a high-fat diet for 8 weeks and injection of streptozotocin. LRG and autophagy inhibitors were used to investigate the protective effect of LRG on pancreatic β-cells in vivo. Metabolic indices were measured and pancreatic autophagy was detected. In the INS-1 cells, viability was higher in the FFA + LRG group compared with the FFA group, while the apoptotic rate was lower (P<0.05). The light chain 3B and p62 autophagy-associated proteins were upregulated by LRG, while ATG7 and Beclin1 were downregulated. Autophagy inhibitors reduced the protective effect of LRG in the FFA-treated INS-1 cells. The type 2 diabetes mouse model was successfully established, termed the HF group, in which LRG was observed to reduce body weight and decrease levels of fasting blood glucose, total cholesterol, serum insulin, triglyceride, low density lipoprotein-cholesterol and glycosylated hemoglobin (P<0.05), compared with the HF group. However, chloroquine treatment abrogated these effects (P<0.05, compared with the HF + LRG group; P>0.05, compared with the HF group). Autophagosomes were also observed under ECM in the pancreatic tissues of mice in the HF + LRG group. Therefore, LRG induced autophagy and exerted protective effects on pancreatic β-cells in vitro and in vivo.

Observational Registry of Basal Insulin Treatment (ORBIT) in patients with type 2 diabetes uncontrolled with oral antihyperglycaemic drugs: Real-life use of basal insulin in China.

To examine treatment patterns following basal insulin (BI) introduction in type 2 diabetes mellitus (T2DM) patients under real‐world conditions across China.

Observational Registry of Basal Insulin Treatment (ORBIT) in Patients with Type 2 Diabetes Uncontrolled by Oral Hypoglycemic Agents in China--Study Design and Baseline Characteristics.

BACKGROUND Efficacy of basal insulin (BI) has been well studied by randomized controlled trials, but the impact of BI on glycemic control in the real world has not been well documented. The Observational Registry for BI Treatment (ORBIT) study is designed to evaluate the real-life outcomes of BI in China. MATERIALS AND METHODS Participants with type 2 diabetes (n=19,894), from December 2011 to June 2013, inadequately controlled on oral hypoglycemic agents (OHAs) were initiated on BI treatment from 209 hospitals in all the eight regions in Mainland China. Data for each patient on use of OHAs and insulin (type and dose), glycemic control, hypoglycemic episodes, body weight, quality of life, and costs were collected at baseline and 3 and 6 months. RESULTS For the 18,995 participants who were eligible for baseline analysis, mean±SD age was 55.4±10.4 years, with 52.5% males. The mean duration of diabetes was 6.4±5.3 years and was positively associated with the economic level of eight regions. Before initiation of BI, patients had a mean hemoglobin A1c level of 9.6±2.0% with a fasting plasma glucose level of 11.7±4.0 mmol/L. Of the patients, 35.5% had some diabetes complications. Metformin, sulfonylureas, and α-glycosidase inhibitors were the most commonly used OHAs. The proportions of patients using one, two, or more than two OHAs before BI initiation were 48.4%, 42.7%, and 8.9%, respectively. CONCLUSIONS To the best of our knowledge, the ORBIT study is the largest registry study to evaluate glycemic outcomes and safety of BI in real-world China. Baseline data indicate delays in initiation of BI in the majority of patients with type 2 diabetes in China.

Modulation of the gut microbiome: a systematic review of the effect of bariatric surgery

OBJECTIVE Bariatric surgery is recommended for patients with obesity and type 2 diabetes. Recent evidence suggested a strong connection between gut microbiota and bariatric surgery. DESIGN Systematic review. METHODS The PubMed and OVID EMBASE were used, and articles concerning bariatric surgery and gut microbiota were screened. The main outcome measures were alterations of gut microbiota after bariatric surgery and correlations between gut microbiota and host metabolism. We applied the system of evidence level to evaluate the alteration of microbiota. Modulation of short-chain fatty acid and gut genetic content was also investigated. RESULTS Totally 12 animal experiments and 9 clinical studies were included. Based on strong evidence, 4 phyla (Bacteroidetes, Fusobacteria, Verrucomicrobia and Proteobacteria) increased after surgery; within the phylum Firmicutes, Lactobacillales and Enterococcus increased; and within the phylum Proteobacteria, Gammaproteobacteria, Enterobacteriales Enterobacteriaceae and several genera and species increased. Decreased microbial groups were Firmicutes, Clostridiales, Clostridiaceae, Blautia and Dorea. However, the change in microbial diversity is still under debate. Faecalibacterium prausnitzii, Lactobacillus and Coprococcus comes are implicated in many of the outcomes, including body composition and glucose homeostasis. CONCLUSIONS There is strong evidence to support a considerable alteration of the gut microbiome after bariatric surgery. Deeper investigations are required to confirm the mechanisms that link the gut microbiome and metabolic alterations in human metabolism.

Gut microbiota after Roux-en-Y gastric bypass and sleeve gastrectomy in a diabetic rat model: Increased diversity and associations of discriminant genera with metabolic changes.

Recent work with gut microbiota after bariatric surgery is limited, and the results have not been in agreement. Given the role of the gut microbiota in regulating host metabolism, we explored the effect of Roux‐en‐Y gastric bypass (RYGB) and sleeve gastrectomy (SG) on the modifications of gut microbiota with regard to the potential influence of food intake and/or weight loss and examined their links with host metabolism. Zucker diabetic fatty rats were divided into the following groups: RYGB; sham‐operated with pair‐fed as RYGB; sham‐operated fed ad libitum; and SG. The metabolic effects and gut microbiota profile were analyzed 10 weeks postoperatively. Associations between discriminating genera and metabolic markers after RYGB were explored. The 2 procedures induced similar glucose improvement and increased flora diversity after 10 weeks compared with sham‐operated groups. RYGB induced a marked higher relative abundance of Proteobacteria/Gammaproteobacteria and Betaproteobacteria and increased emergence of Fusobacteria and Clostridium, whereas SG resulted in more abundant Actinobacteria compared with other groups. Most of the 12 discriminant genera correlated with changes in metabolic phenotype, but only 28.6% of these correlations were independent of weight, and 4 discriminant genera still negatively correlated with serum insulin level independent of food intake and weight loss after RYGB. These data demonstrate that RYGB and SG surgery produced similar diversity but different microbiota compositions changes in Zucker diabetic fatty rats. These findings stimulate deeper explorations of functions of the discriminate microbiota and the mechanisms linking postsurgical modulation of gut microbiota and improvements in insulin resistance.