Interventional Clinical Trials on Diabetic Peripheral Neuropathy: A Retrospective Analysis

Ginsenoside Rb1 alleviates chronic intermittent hypoxia-induced diabetic cardiomyopathy in db/db mice by regulating the adenosine monophosphate-activated protein kinase/Nrf2/heme oxygenase-1 signaling pathway

OBJECTIVE

To examine the protective effect of ginsenoside Rb1 (Rb1), the main component of Renshen (), on cardiomyopathy in db/db mice exposed to chronic intermittent hypoxia (CIH) and explore the potential underlying mechanism of Rb1 in treating diabetic cardiomyopathy (DCM).

METHODS

The db/db mice were randomly separated into five groups: normal control group, model group, Rb1 20 mg/kg group, Rb1 40 mg/kg group, and glucagon-like peptide-1 (GLP-1) group. Mice were exposed to air-condition or CIH for 8 weeks, and Rb1 and GLP-1 were administrated before CIH exposure every day. Oral glucose tolerance test (OGTT), intraperitoneal insulin tolerance test (IPITT), total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) were detected to evaluate glycolipid metabolism. The level of insulin was detected by a mouse enzyme-linked immunosorbent assay (ELISA). Cardiac function was detected by echocardiography, and myocardial pathology was observed by hematoxylin-eosin and Masson staining. The expression of collagen Ⅰ and collagen Ⅲ was detected by immunohistochemistry. Adenosine monophosphate-activated protein kinase (AMPK)/Nrf2/heme oxygenase-1 (HO-1) signaling pathway was detected by Western blot and immunofluorescence.

RESULTS

Rb1 treatment could improve glucose tolerance and the level of cardiac function indexes, and inhibit the level of oxidative stress indexes and the expression of collagen Ⅰ and collagen Ⅲ. Moreover, Rb1 treatment enhanced AMPK phosphorylation and increased Nrf2 and HO-1 expression.

CONCLUSION

Rb1 treatment alleviated CIH-induced diabetic cardiomyopathy and glycolipid metabolism disorders in db/db mice by inhibiting oxidative stress and regulating the AMPK/Nrf2/HO-1 signaling pathway.

Issues and challenges in diabetic neuropathy management: A narrative review

Diabetic neuropathy (DN) is a devastating disorder with an increasing prevalence globally. This epidemic can pose a critical burden on individuals and com-munities, subsequently affecting the productivity and economic output of a country. With more people living a sedentary lifestyle, the incidence of DN is escalating worldwide. Many researchers have relentlessly worked on ways to combat this devastating disease. Their efforts have given rise to a number of commercially available therapies that can alleviate the symptoms of DN. Unfortunately, most of these therapies are only partially effective. Worse still, some are associated with unfavorable side effects. This narrative review aims to highlight current issues and challenges in the management of DN, especially from the perspective of molecular mechanisms that lead to its progression, with the hope of providing future direction in the management of DN. To improve the approaches to diabetic management, the suggested resolutions in the literature are also discussed in this review. This review will provide an in-depth understanding of the causative mechanisms of DN, apart from the insights to improve the quality and strategic approaches to DN management.

Association of Non-Dipping Blood Pressure Patterns with Diabetic Peripheral Neuropathy: A Cross-Sectional Study among a Population with Diabetes in Greece

Diabetic peripheral neuropathy (DPN) is present in 20-50% of cases with diabetes. The pathophysiology of DPN is not yet clear regarding hypertension (HTN). The aim of this study was to assess the association between the stages of DPN and HTN in a Greek population with diabetes. We examined 102 adults for diabetic neuropathy (DPN) from November 2020 to December 2021, using the Toronto Clinical Neuropathy Scale System (TCNSS) to categorize them into two groups (no/mild DPN versus medium/severe DPN). Ambulatory blood pressure monitoring was performed to evaluate their hypertensive status. Univariate and multivariate logistic regression analyses were performed to assess the association between the stage of DPN and HTN. The multivariate analysis, considering sex, age, and dipping status, did not show statistically significant associations between stages of HTN and DPN. However, in contrast to dippers, non-dippers had an almost four-times higher risk of developing medium-to-severe DPN (odds ratio (OR) 3.93; 95% confidence interval (CI) [1.33-11.64]); females, in contrast to males, had a 65% lower risk of developing moderate/severe DPN (OR 0.35; 95%CI [0.14-0.92]). In conclusion, our findings showed no statistically significant associations between DPN and HTN; however, dipping status, hyperglycemia, and female sex were shown to play a role in the pathophysiology of DPN.

First-in-Human Single-Ascending-Dose, Multiple-Dose, and Food Interaction Studies of NRD.E1, an Innovative Nonopioid Therapy for Painful Diabetic Peripheral Neuropathy

Painful diabetic peripheral neuropathy is characterized by burning, stabbing, or electric shock-type pain, which severely impacts day-to-day functioning and quality of life. Here, we report the results of 3 phase I studies with NRD135S.E1 (referred to as NRD.E1), a new, orally available chemical entity, presently developed for the treatment of painful diabetic peripheral neuropathy. The first study was a first-in-human, randomized, placebo-controlled, single-ascending-dose study, where NRD.E1 was administered to healthy male subjects in single dosages ranging from 300 to 1200 mg. The second study was a randomized, placebo-controlled multiple-dose study, where healthy male subjects received 300 mg of NRD.E1 once daily for 5 consecutive days. The third study was an open-label food interaction study in healthy men and women following a crossover design, where NRD.E1 was administered under fed and fasted conditions at 40 mg. The studies revealed dose-dependent absorption, increased exposure to NRD.E1 when administered with food, and no relevant accumulation after once-daily administration. All 3 phase I studies consistently showed rapid absorption of orally administered NRD.E1 followed by fast elimination, mainly via metabolization (glucuronidation), and small secondary increases in plasma concentrations. NRD.E1 was well tolerated, with no subject discontinuation due to treatment-emergent adverse events in any study.