Vildagliptin, a dipeptidyl peptidase-4 inhibitor, for the treatment of type 2 diabetes

Vildagliptin showed anti-epileptic effects and promoted subthreshold A-type potassium currents by regulating DPPs and Kv4s binding

The subthreshold A-type potassium current (Isa), mediated by Kv4, is a hyperpolarizing current that decreases neuronal excitability. The Kv4 accessory proteins, DPP6 and DPP10 (DPPs), modulate the current. Thus, agents that modify the binding of DPPs to these channels affect neuronal excitability. Vildagliptin inhibits DPP4, a protein with structural similarities to DPPs. In this study, we investigated whether vildagliptin, an antidiabetic medication, exhibits anti-epileptic properties. Seizures were induced in rats by injecting pentylenetetrazole (PTZ), and vildagliptin at different doses was administered one hour before the PTZ injection. Vildagliptin treatment delayed the onset of epileptiform activity and reduced seizure duration and frequency. A dose-dependent decrease in DPPs was observed in vildagliptin-treated rats. We induced epileptic activity in cultured hippocampal neurons and found that treatment with vildagliptin suppressed the firing frequency. We found that the Isa current in cultured neurons was mediated by Kv4s and suppressed in epileptic neurons. Furthermore, the Kv4s to DPPs ratio in the channel complex was decreased in epileptic neurons, but was restored to a normal level in vildagliptin-treated neurons. In conclusion, the anti-epileptic effects of vildagliptin were likely mediated by the suppression of seizure-induced DPP6 and DPP10 expression and decreased membrane excitability by restoring Isa current density via the regulation of DPPs and Kv4s binding, indicating that vildagliptin may be a novel treatment option for epileptic patients.

Changes in clinical trials of endocrine disorder and metabolism and nutrition disorder drugs in mainland China over 2010-2019

With the improvements in relevant policies, laws, and regulations regarding drug clinical trials in China, the quantity and quality of drug clinical trials have gradually improved, and the development prospects of drug clinical trials for endocrine disorders and metabolism and nutrition disorders are promising. Based on information from the clinical trials from the online drug clinical trial registration platform of the National Medical Products Administration, we aimed to review and evaluate the development of clinical trials of drugs for endocrine disorders and metabolism and nutrition disorders in mainland China from 2010 to 2019, as well as the trends over time. A total of 861 trials were carried out on 254 types of drugs for endocrine disorders and metabolism and nutrition disorders, among which 531 (61.67%) involved endocrine disorders, and 330 (38.33%) addressed metabolism and nutrition disorders. The annual number of clinical trials has been increasing gradually, with a significant increase in 2017. Among them, the proportion of clinical trials with Chinese epidemiological characteristics was relatively large (Wu, Annual Report on Development Health Management and Health Industry in China, 2018). The largest number of trials were for diabetes drugs (55.63%), followed by trials of drugs for hyperlipidemia (19.4%) and those for hyperuricemia (7.9%). It was found that the geographical area of the leading units also showed obvious unevenness according to the analysis of the test unit data. Based on the statistics and evaluation of the data, comprehensive information is provided to support the cooperation of global pharmaceutical R&D companies and research units in China and the development of international multicenter clinical trials in China. This work additionally provides clinical trial units with a self‐evaluation of scientific research competitiveness and hospital development strategies. At the same time, it provides a reference with basic data for sponsors and stakeholders in these trials to determine their development strategy goals.

Combined dipeptidyl peptidase-4 inhibitor with low-dose testosterone exerts greater efficacy than monotherapy on improving brain function in orchiectomized obese rats

Both obesity and orchiectomy lead to the development of brain pathologies and cognitive decline. Testosterone replacement therapy (2 mg/kg/day TRT) and dipeptidyl peptidase-4 inhibitor (vildagliptin) improved cognition in orchiectomized rats, and obese rats. However, both had no beneficial effects in brain of orchiectomized-obese rats. TRT (>2 mg/kg/day) is possible to attenuate brain defects in those rats, but high dose of TRT causes adverse effects. Then, combined effect of low-dose TRT (1 mg/kg/day) and vildagliptin on brain and cognitive functions in orchiectomized-obese rats should be investigated. Sixty male rats were fed with either a normal diet (ND) or a high-fat diet (HFD) for 28 weeks. At week 13, both ND and HFD-fed rats had either a sham-operation or an orchiectomy. At week 25, orchiectomized rats were treated with either: a vehicle, 2 mg/kg/day TRT, vildagliptin (3 mg/kg/day) or a combined vildagliptin with 1 mg/kg/day TRT for 4 weeks. Then, metabolic parameters, brain and cognitive functions were determined. Hippocampal oxidative stress, apoptosis, dendritic spine loss, microglial hyperactivity, and cognitive decline were found in orchiectomized ND-fed rats and sham-operated HFD-fed rats. Interestingly, orchiectomy aggravated these brain pathologies and cognitive decline in HFD-fed rats. In orchiectomized ND-fed rats, all treatments restored brain and cognitive functions. In orchiectomized HFD-fed rats, monotherapies ameliorated these brain pathologies, while the combined therapies had the greatest beneficial effect on the brains. These findings suggest the combined therapies may be the best therapeutic approach for restoring brain functions in the orchiectomized-obese condition.

DIABETES MELLITUS IN PATIENTS WITH LIVER CIRRHOSIS: NEW TREATMENT OPTIONS

In economically developed countries, cirrhosis is one of the six leading causes of death at the age of 35–60 years and ranges from 14 to 30 cases per 100000 population. In the world 40 million people die of cirrhosis each year. At 6% of the population of the Russian Federation there is a diabetes mellitus. The combination of diabetes mellitus in patients with cirrhosis of the liver is a common comorbid pathology. Diabetes mellitusis a risk factor for the development of liver cirrhosis, and the incidence of combination of both diseases is quite high, although the frequency of occurrence varies. About 80% of patients with LC may have impaired glucose metabolism, and 30% have diabetes mellitus. Prospective studies have shown that diabetes is associated with an increased risk of developing hepatic complications and death in patients with cirrhosis of the liver. Diabetes mellitus increases the risk of complications of liver cirrhosis of any etiology (varicose veins of the esophagus, hepatic encephalopathy, hepatic-cell insufficiency) and subsequent survival. The incidence, frequency of hospitalizations and mortality from this combined pathology are very high. There are common mechanisms that provoke metabolic and autoimmune disorders in the development of chronic hepatitis and cirrhosis, leading to steatosis, insulin resistance, impaired glucose tolerance and the development of diabetes mellitus. There are certain features of the evaluation of the compensation of carbohydrate metabolism in patients with cirrhosis of the liver, anemia and impaired protein metabolism. Effective control of glycemia can have a beneficial effect on the treatment of these patients. However, few studies have evaluated the efficacy and safety of antidiabetic drugs and the effect of diabetes treatment on morbidity and mortality in patients with cirrhosis. Previously it was believed that in the presence of cirrhosis the only treatment remains insulin. At present, in connection with the emergence of modern groups of hypoglycemic drugs, as well as new approaches to the treatment of type 2 diabetes, this concept has radically changed. Unfortunately, the issues of correction of carbohydrate metabolism in patients with cirrhosis of the liver are practically not covered in the world literature. This article deals with the correction of carbohydrate metabolism in patients with cirrhosis and hepatocellular insufficiency of insulin analogs, biguanides, drugs with incretin effect — dipeptidyl peptidase‑4 inhibitors, agonists of glucagon-like peptide‑1, inhibitors of sodium-glucose cotransporter 2 diabetes. Particular attention is paid to the development of hepatocellular insufficiency and portal hypertension in patients with cirrhosis and type 2 diabetes, as well as processes for their prevention and insulin alternative correction methods.

Effectiveness of Vildagliptin in Clinical Practice: Pooled Analysis of Three Korean Observational Studies (the VICTORY Study)

The present observational study aimed to evaluate the clinical effectiveness of vildagliptin with metformin in Korean patients with type 2 diabetes mellitus (T2DM). Data were pooled from the vildagliptin postmarketing survey (PMS), the vildagliptin/metformin fixed drug combination (DC) PMS, and a retrospective observational study of vildagliptin/metformin (fixed DC or free DC). The effectiveness endpoint was the proportion of patients who achieved a glycemic target (HbA1c) of ≤7.0% at 24 weeks. In total, 4303 patients were included in the analysis; of these, 2087 patients were eligible. The mean patient age was 56.99 ± 11.25 years. Overall, 58.94% patients achieved an HbA1c target of ≤7.0% at 24 weeks. The glycemic target achievement rate was significantly greater in patients with baseline HbA1c < 7.5% versus ≥7.5% (84.64% versus 43.97%), receiving care at the hospital versus clinic (67.95% versus 52.33%), and receiving vildagliptin/metformin fixed DC versus free DC (70.69% versus 55.42%). Multivariate logistic regression analysis indicated that disease duration (P < 0.0001), baseline HbA1c (P < 0.0001), and DC type (P = 0.0103) had significant effects on drug effectiveness. Vildagliptin plus metformin appeared as an effective treatment option for patients with T2DM in clinical practice settings in Korea.