Disruptions in hepatic glucose metabolism are involved in the diminished efficacy after chronic treatment with glucokinase activator

Compromised chronic efficacy of a glucokinase activator AZD1656 in mouse models for common human GCKR variants

Glucokinase activators (GKAs) have been developed as blood glucose lowering drugs for type 2 diabetes. Despite good short-term efficacy, several GKAs showed a decline in efficacy chronically during clinical trials. The underlying mechanisms remain incompletely understood. We tested the hypothesis that deficiency in the liver glucokinase regulatory protein (GKRP) as occurs with common human GCKR variants affects chronic GKA efficacy. We used a Gckr-P446L mouse model for the GCKR exonic rs1260326 (P446L) variant and the Gckr-del/wt mouse to model transcriptional deficiency to test for chronic efficacy of the GKA, AZD1656 in GKRP-deficient states. In the Gckr-P446L mouse, the blood glucose lowering efficacy of AZD1656 (3 mg/kg body wt) after 2 weeks was independent of genotype. However after 19 weeks, efficacy was maintained in wild-type but declined in the LL genotype, in conjunction with raised hepatic glucokinase activity and without raised liver lipids. Sustained blood glucose lowering efficacy in wild-type mice was associated with qualitatively similar but more modest changes in the liver transcriptome compared with the P446L genotype, consistent with GKA therapy representing a more modest glucokinase excess than the P446L genotype. Chronic treatment with AZD1656 in the Gckr-del/wt mouse was associated with raised liver triglyceride and hepatocyte microvesicular steatosis. The results show that in mouse models of liver GKRP deficiency in conjunction with functional liver glucokinase excess as occurs in association with common human GCKR variants, GKRP-deficiency predisposes to declining efficacy of the GKA in lowering blood glucose and to GKA induced elevation in liver lipids.

Managing Post-Transplant Diabetes Mellitus after Kidney Transplantation: Challenges and Advances in Treatment

Kidney transplantation is the most effective treatment for end-stage renal failure but is associated with complications, including post-transplant diabetes mellitus (PTDM). It affects the quality of life and survival of patients and the transplanted organ. It can cause complications, including infections and episodes of acute rejection, further threatening graft survival. The prevalence of PTDM, depending on the source, can range from 4 to 30% in transplant patients. This article aims to discuss issues related to diabetes in kidney transplant patients and the latest treatments. Knowledge of the mechanisms of action of immunosuppressive drugs used after transplantation and their effect on carbohydrate metabolism is key to the rapid and effective detection of PTDM. Patient therapy should not only include standard management such as lifestyle modification, insulin therapy or pharmacotherapy based on well-known oral and injection drugs. New opportunities are offered by hypoglycemic drugs still in clinical trials, including glucokinase activators, such as dorzagliatin, ADV-1002401, LY2608204, TMG-123, imeglimine, amycretin and pramlintide. Although many therapeutic options are currently available, PTDM often creates uncertainty about the most appropriate treatment strategy. Therefore, more research is needed to individualize therapeutic plans and monitor these patients.

Efficacy and safety of dorzagliatin, a novel glucokinase activators, in the treatment of T2DM: A meta-analysis of randomized controlled trials

OBJECT

To evaluate the efficacy and safety of dorzagliatin for the treatment of type 2 diabetes (T2DM).

METHODS

Seven databases were systematically searched, spanning the interval from 2016 to August 2023. Randomized controlled trials (RCTS) comparing dorzagliatin with placebo for the treatment of T2DM were applicable for containing this study. The relevant data were extracted, and a meta-analysis was implemented using RevMan 5.4 software.

RESULTS

A total of 3 studies involving 1332 patients were included. We use glycated hemoglobin (HbA1c) levels as the major indicator of efficacy, FBG, 2h postprandial blood glucose, Homa-β and Homa-IR to be Secondary outcome measures. Compared with placebo group, dorzagliatin significantly reduced blood glucose levels as well as enhanced insulin resistance. In terms of safety, no serious adverse events occurred. However, lipid-related indicators, especially triglycerides levels, and the incidence of hypoglycemia were higher in patients in the dorzagliatin group compared with those in the control group, but the increase from baseline was mild.

CONCLUSIONS

Dorzagliatin exerted favorable effects in hypoglycemic control, effectively reduced the HbA1c, FBG, and 2h postprandial blood glucose levels in T2DM patients, stimulated the secretion of insulin during the initial phase, and exerted a consistent hypoglycemic effect. However, the incidence of adverse events such as elevated blood lipids and cardiovascular risk warrants further investigations through long-term clinical trials.