1.
Serum Vitamin D Affected Type 2 Diabetes though Altering Lipid Profile and Modified the Effects of Testosterone on Diabetes Status.
Wang, L, Liu, X, Hou, J, Wei, D, Liu, P, Fan, K, Zhang, L, Nie, L, Li, X, Huo, W, et al
Nutrients. 2020;(1)
Abstract
Numerous studies have investigated the associations between serum vitamin D or testosterone and diabetes; however, inconsistencies are observed. Whether there is an interaction between vitamin D and testosterone and whether the lipid profile (total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)) mediates the association between vitamin D and diabetes is unclear. To investigate the effect of vitamin D and testosterone on impaired fasting glucose (IFG) or type 2 diabetes mellitus (T2DM), 2659 participants from the Henan Rural Cohort were included in the case-control study. Generalized linear models were utilized to estimate associations of vitamin D with IFG or T2DM and interactive effects of vitamin D and testosterone on IFG or T2DM. Principal component analysis (PCA) and mediation analysis were used to estimate whether the lipid profile mediated the association of vitamin D with IFG or T2DM. Serum 25(OH)D3, 25(OH)D2, and total 25(OH)D levels were negatively correlated with IFG (odds ratios (ORs) (95% confidence intervals (CIs)): 0.99 (0.97, 1.00), 0.85 (0.82, 0.88), and 0.97 (0.96, 0.98), respectively). Similarity results for associations between serum 25(OH)D2 and total 25(OH)D with T2DM (ORs (95%CIs): 0.84 (0.81, 0.88) and 0.97 (0.96, 0.99)) were observed, whereas serum 25(OH)D3 was negatively correlated to T2DM only in the quartile 2 (Q2) and Q3 groups (both p < 0.05). The lipid profile, mainly TC and TG, partly mediated the relationship between 25(OH)D2 or total 25(OH)D and IFG or T2DM and the proportion explained was from 2.74 to 17.46%. Furthermore, interactive effects of serum 25(OH)D2, total 25(OH)D, and testosterone on T2DM were observed in females (both p for interactive <0.05), implying that the positive association between serum testosterone and T2DM was vanished when 25(OH)D2 was higher than 10.04 ng/mL or total 25(OH)D was higher than 40.04 ng/mL. Therefore, ensuring adequate vitamin D levels could reduce the prevalence of IFG and T2DM, especially in females with high levels of testosterone.
2.
Association between Normal Thyroid Hormones and Diabetic Retinopathy in Patients with Type 2 Diabetes.
Zou, J, Li, Z, Tian, F, Zhang, Y, Xu, C, Zhai, J, Shi, M, Wu, G, Zhang, Z, Yang, C, et al
BioMed research international. 2020;:8161797
Abstract
The relationship between normal thyroid function and type 2 diabetes mellitus (T2DM) has been a particular focus for concern. The present study determined the relationship between thyroid hormone levels and the prevalence of diabetic retinopathy (DR) in T2DM patients. A cross-sectional study (n = 633) was performed in Xi'an, Shaanxi Province, China. Subjects were evaluated for anthropometric measurements, thyroid function, and diabetic retinopathy. Logistic regression models were used to assess the relationships between thyroid hormones and DR. Of 633 patients, 243 (38.4%) patients suffered from DR. The prevalence of DR showed a significantly decreasing trend across the quartiles based on free triiodothyronine (FT3) (FT3 quartile 1 group [FT3-Q1] <4.35 pmol/L, FT3 quartile 2 group [FT3-Q2] 4.35-4.70 pmol/L, FT3 quartile 3 group [FT3-Q3] 4.70-5.08 pmol/L, and FT3 quartile 4 group [FT3-Q4] ≥5.08 pmol/L) (56.7%, 42.5%, 33.1%, 23.8%, P < 0.001). In comparison with all participants categorized in FT3-Q1, the multivariable adjusted odds ratios (95% confidence interval) of DR in FT3-Q2, FT3-Q3, and FT3-Q4 were 0.587 (0.340-1.012), 0.458 (0.258-0.813), and 0.368 (0.201-0.673), (P = 0.055, P = 0.008, P = 0.001), respectively. FT3 levels within the normal range are negatively associated with DR in euthyroid patients with type 2 diabetes. Further studies should be aimed at clarifying the relationship between thyroid hormones and T2DM.
3.
Dorzagliatin monotherapy in Chinese patients with type 2 diabetes: a dose-ranging, randomised, double-blind, placebo-controlled, phase 2 study.
Zhu, D, Gan, S, Liu, Y, Ma, J, Dong, X, Song, W, Zeng, J, Wang, G, Zhao, W, Zhang, Q, et al
The lancet. Diabetes & endocrinology. 2018;(8):627-636
Abstract
BACKGROUND Glucokinase acts as a glucose sensor in the pancreas and a glucose processor in the liver, and has a central role in glucose homoeostasis. Dorzagliatin is a new, dual-acting, allosteric glucokinase activator that targets both pancreatic and hepatic glucokinases. Dorzagliatin has good pharmacokinetic and pharmacodynamic properties in humans, and provides effective 24-h glycaemic control and improves glucose sensitivity in patients with type 2 diabetes. We aimed to assess the efficacy and safety of dorzagliatin monotherapy at different doses in Chinese patients with type 2 diabetes. METHODS In this multicentre, randomised, double-blind, placebo-controlled, phase 2 study, we randomly assigned (1:1:1:1:1) patients to receive oral placebo or one of four doses of oral dorzagliatin (75 mg once a day, 100 mg once a day, 50 mg twice a day, or 75 mg twice a day) using permuted-block randomisation, with a block size of ten and without stratification. Eligible patients were men or non-fertile women (aged 40-75 years) with type 2 diabetes who had a BMI of 19·0-30·0 kg/m2, were on a diet and exercise regimen, and were previously untreated or treated with metformin or α-glucosidase inhibitor monotherapy. The study started with a 4-week placebo run-in period followed by a 12-week treatment period. The primary endpoint was the change in HbA1c from baseline to week 12, which was assessed in all patients who received at least one dose of study drug and had both baseline and at least one post-baseline HbA1c value. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02561338. FINDINGS Between Sept 29, 2015, and Aug 17, 2016, we randomly assigned 258 patients to one of the five study groups. At the end of 12 weeks, the least squares mean change in HbA1c from baseline was -0·35% (95% CI -0·60 to -0·10) in the placebo group, -0·39% (-0·64 to -0·14) in the 75 mg once daily group, -0·65% (-0·92 to -0·38) in the 100 mg once daily group, -0·79% (-1·06 to -0·52) in the 50 mg twice daily group, and -1·12% (-1·39 to -0·86) in the 75 mg twice daily group. Compared with the placebo group, the change in HbA1c between baseline and 12 weeks was significant in the 50 mg twice daily (p=0·0104) and the 75 mg twice daily (p<0·0001) groups. The number of adverse events was similar between the treatment groups and the placebo group. There were no reports of drug-related serious adverse events or severe hypoglycaemia. INTERPRETATION Dorzagliatin had a beneficial effect on glycaemic control and was safe and well tolerated over 12 weeks in Chinese patients with type 2 diabetes. FUNDING Hua Medicine, National Major Scientific and Technological Special Project for Significant New Drugs Development, Shanghai Science and Technology Innovation Action Project, Shanghai Pudong District Science and Technology Innovation Action Project, and Shanghai Municipal Commission of Economy and Informatisation Innovation Action Project.