A Claims Database Analysis of Dose-Dependency of Metformin and Incidence of Lactic Acidosis in Japanese Patients with Type 2 Diabetes.

INTRODUCTION: Patients with type 2 diabetes (T2D) in Japan are prescribed a lower dose of metformin that their counterparts in Western countries due to concerns for the risk of lactic acidosis incidence. Here we report our study on the association between high-dose metformin administration and the incidence of lactic acidosis in Japanese patients with T2D. METHODS: A Japanese claims database (April 2008-November 2018) was analyzed. Factors associated with the incidence of lactic acidosis were first identified from the database records by conducting a case-control study, and these were then used as confounding factors in subsequent analyses. The association between high-dose metformin administration (≥ 1000 mg/day) and the incidence of lactic acidosis was compared with that between low-dose metformin (< 1000 mg/day) or no metformin administration and lactic acidosis incidence by using the following approaches: a logistic regression analysis hypothesizing that metformin-associated lactic acidosis is short term; a time-dependent proportional hazard model hypothesizing that the influence of metformin is cumulative; and a case-control study in which lactic acidosis incidence was the case and metformin administration within 3 months prior to the incidence of lactic acidosis (or corresponding date for the control) was the exposure. RESULTS: Prescriptions for biguanide and vitamin B complex and volume depletion were identified as factors associated with the incidence of lactic acidosis. The incidence rate was higher in patients prescribed metformin than in those not receiving metformin; however, it was not higher in those prescribed high-dose metformin compared to those prescribed low-dose metformin. The estimated regression coefficient for high-dose metformin administration was 0.816 (p < 0.001); this was not higher than those for low-dose metformin (1.047), vitamin B complex (2.725) and volume depletion (3.301). The time-dependent proportional hazard analysis did not indicate any effect of metformin prescription. CONCLUSION: The results suggest an association between metformin administration and the incidence of lactic acidosis, but an increase in the incidence rate of lactic acidosis was not observed in those patients receiving high-dose metformin compared to those receiving low-dose metformin.

Effects of resistance training using elastic bands on muscle strength with or without a leucine supplement for 48 weeks in elderly patients with type 2 diabetes.

Type 2 diabetes is associated with sarcopenia. Resistance training and appropriate nutritional therapy are reported to be effective for muscle strength and mass. This study aimed to evaluate the effect of resistance training using elastic bands at home combined with a leucine-rich amino acid supplement on muscle strength, physical function, and muscle mass in elderly type 2 diabetes. We conducted a 48-week prospective single-center randomized controlled trial in 60 patients who were randomly allocated to one of three groups: control (C), resistance exercise (R), and resistance exercise plus supplement (RL). R and RL groups performed daily bodyweight resistance training with elastic bands exercises at home, and the RL group also took 6 g of a leucine-rich amino acid supplement daily. Knee extension strength (muscle strength), grip strength, usual gait speed (physical function), muscle mass, and cognitive function were assessed at 0 and 48 weeks. Although the change in knee extension strength from baseline was significantly increased by 6.4 Nm (95% CI 1.0, 11.7) in the RL group (p = 0.036), no significant difference was observed among the three groups (p = 0.090). Physical function, muscle mass, and cognitive function also had no changes during the study period among the three groups. No additive effect of a leucine-rich amino acid supplement on muscle strength or mass was observed. Although a post hoc analysis comparing with or without resistance training (C group vs. R + RL group) found that knee extension strength was significantly increased (p = 0.028), and cognitive decline was less (p = 0.046) than in the C group.

[Fixed-dose combination].

Many patients with type 2 diabetes mellitus(T2DM) do not achieve satisfactory glycemic control by monotherapy alone, and often require multiple oral hypoglycemic agents (OHAs). Combining OHAs with complementary mechanisms of action is fundamental to the management of T2DM. Fixed-dose combination therapy(FDC) offers a method of simplifying complex regimens. Efficacy and tolerability appear to be similar between FDC and treatment with individual agents. In addition, FDC can enhance adherence and improved adherence may result in improved glycemic control. Four FDC agents are available in Japan: pioglitazone-glimepiride, pioglitazone-metformin, pioglitazone-alogliptin, and voglibose-mitiglinide. In this review, the advantages and disadvantages of these four combinations are identified and discussed.

Modeling infection of spring onion by Puccinia allii in response to temperature and leaf wetness.

The influence of temperature and leaf wetness duration on infection of spring onion (Japanese bunching onion) leaves by Puccinia allii was examined in controlled-environment experiments. Leaves of potted spring onion plants (Allium fistulosum cv. Yoshikura) were inoculated with urediniospores and exposed to 6.5, 10, 15, 22, or 27 h of wetness at 5, 10, 15, 20, or 25 degrees C. The lesion that developed increased in density with increasing wetness duration. Relative infection was modeled as a function of both temperature and wetness duration using the modified version of Weibull's cumulative distribution function (R(2) = 0.9369). Infection occurred between 6.5 and 27 h of leaf wetness duration at 10, 15, 20, and 25 degrees C and between 10 and 27 h at 5 degrees C, and increased rapidly between 6.5 and 15 h of wetness at 10, 15, and 20 degrees C. At 25 degrees C, few uredinia developed regardless of the wetness duration. Parameter H, one of eight parameters used in the equation and which controls the asymmetry in the response curve, varied markedly according to the temperature, so that the model could be improved by representing H as a function of wetness duration (R(2) = 0.9501).

Protein-tyrosine phosphatase 1B as new activator for hepatic lipogenesis via sterol regulatory element-binding protein-1 gene expression.

Like hyperglycemia, postprandial (diet-induced) hypertriglyceridemia is thought to play crucial roles in the pathogenesis of insulin resistant/metabolic syndrome. Sterol regulatory element-binding protein-1 (SREBP-1) is a key transcription factor to induce postprandial hypertriglyceridemia. We found that insulin-resistant rats fed a diet high in fructose showed an increased proteintyrosine phosphatase 1B (PTP1B) content with strong expression of SREBP-1 mRNA in the liver. To clarify the association of PTP1B with SREBP-1 gene expression, we overexpressed PTP1B in rat hepatocytes, which led to increased mRNA content and promoter activity of SREBP-1a and -1c, resulting in the increased mRNA expression of fatty-acid synthase, one of the SREBP-1-responsive lipogenic genes. Because PTP1B overexpression increased phosphatase 2A (PP2A) activity, we inhibited PP2A activity by expression of its selective inhibitor, SV40 small T antigen and found that this normalized the PTP1B-enhanced SREBP-1a and -1c mRNA expressions through activation of the Sp1 site. These results indicate that PTP1B may regulate gene expression of SREBP-1 via enhancement of PP2A activity, thus mediating hepatic lipogenesis and postprandial hypertriglyceridemia. We demonstrate here a unique serial activation of the PTP1B-PP2A axis as a novel mechanism for the regulation of gene expression in the biosynthesis of triglyceride.