A primer on metabolic memory: why existing diabesity treatments fail

Mechanism of metabolic memory: progression in diabetic nephropathy—a descriptive review

Diabetes mellitus and its complications exploit significantly impact global human well-being and economic burden. Previous studies and clinical trials have provided insights into the concept of metabolic memory, which sustains even after hyperglycemia has been resolved, causing diabetic complications completely. The term “metabolic memory” refers to the body’s abnormal metabolism, which can have long-term effects and influence both health and disease conditions. It involves various molecular processes causing cellular shifts, tissue and organ dysfunctions, disease progression, and effects on offspring. The conceptual framework of metabolic memory is defined and strengthened, offering a comprehensive understanding of the underlying causes of diabetic nephropathy (DN) and providing a potential new approach for diagnosing and treating the disease. In this review, we elucidated the importance, characteristics, cellular and molecular importance, and therapeutic intervention to eradicate metabolic memory in DN once hyperglycemia has been eliminated. The regulation of metabolic memory is assisted based on an epigenetic mechanism. Therefore, this report traces the significant factors involved in regulating epigenetic modifications such as DNA methylation, histone modification, and chromatin remodeling. This mechanism significantly triggers epigenetic regulation, leading to glucose stress, oxidative stress induction, and apoptosis, causing DN. It occurs beyond various signaling cascades, resulting in alterations in transcription factors and receptor molecules, which enhance the metabolic memory in the post-sustenance of hyperglycemia. This condition can be modulated based on therapeutic interventions involving lifestyle modification and the inclusion of natural substances like bioactive compounds, polyphenols, and terpenoids in the diet, followed by medications acting as epigenetic modifiers.

An analysis of urodynamic parameters in diabetic and nondiabetic women

OBJECTIVES

Diabetes is highly prevalent worldwide, with an estimated 536 million living with diabetes in 2021, and that number projected to increase to 783 million by 2045. Diabetic bladder dysfunction is thought to affect up to 60%-90% of individuals with diabetes and can significantly impact quality of life. Despite the prevalence of diabetic bladder dysfunction, the exact pathophysiological mechanism, and resulting clinical presentation, remains debated. Our objective was to compare urodynamic parameters between diabetic and nondiabetic women, assessing the impact of various markers of diabetes severity on bladder function.

METHODS

A retrospective chart review was conducted on female patients aged 18 and above who underwent urodynamic studies at a single tertiary care university hospital system from 2014 to 2020. Patients were categorized based on diabetes status, and diabetes severity including duration of disease, hemoglobin A1c levels, insulin dependence, and markers of end-organ dysfunction. Urodynamic variables, including compliance, bladder voided efficiency, bladder contractility index, postvoid residual, maximum flow rate, capacity, voided volume, and detrusor overactivity, were assessed by two independent reviewers. Statistical analyses were performed to assess the impact of diabetes and diabetic severity on urodynamic parameters.

RESULTS

A total of 652 female patients were included in the study, of which, 152 (23.3%) had diabetes, with an average duration of diagnosis of 82.3 months. Diabetic women were older and had higher body mass index compared to nondiabetic women. Diabetic retinopathy and neuropathy were present in 18% and 54.6% of diabetic patients, respectively. Significant differences in urodynamic parameters were observed between diabetic and nondiabetic women, with diabetic women showing higher rates of detrusor overactivity (p = 0.01), particularly associated with increasing BMI (p = 0.03). However, classic markers of diabetes severity including duration, as well as markers of end-organ damage, showed mixed associations with urodynamic changes.

CONCLUSIONS

Despite the prevalence of diabetic bladder dysfunction and its impact on patient quality of life, the exact mechanisms and clinical presentation remain elusive. Our study highlights the significant differences in urodynamic parameters between diabetic and nondiabetic women, emphasizing the need for further research into the relationship between diabetes and diabetic bladder dysfunction.

A New Application for Cenicriviroc, a Dual CCR2/CCR5 Antagonist, in the Treatment of Painful Diabetic Neuropathy in a Mouse Model

The ligands of chemokine receptors 2 and 5 (CCR2 and CCR5, respectively) are associated with the pathomechanism of neuropathic pain development, but their role in painful diabetic neuropathy remains unclear. Therefore, the aim of our study was to examine the function of these factors in the hypersensitivity accompanying diabetes. Additionally, we analyzed the analgesic effect of cenicriviroc (CVC), a dual CCR2/CCR5 antagonist, and its influence on the effectiveness of morphine. An increasing number of experimental studies have shown that targeting more than one molecular target is advantageous compared with the coadministration of individual pharmacophores in terms of their analgesic effect. The advantage of using bifunctional compounds is that they gain simultaneous access to two receptors at the same dose, positively affecting their pharmacokinetics and pharmacodynamics and consequently leading to improved analgesia. Experiments were performed on male and female Swiss albino mice with a streptozotocin (STZ, 200 mg/kg, i.p.) model of diabetic neuropathy. We found that the blood glucose level increased, and the mechanical and thermal hypersensitivity developed on the 7th day after STZ administration. In male mice, we observed increased mRNA levels of Ccl2, Ccl5, and Ccl7, while in female mice, we observed additional increases in Ccl8 and Ccl12 levels. We have demonstrated for the first time that a single administration of cenicriviroc relieves pain to a similar extent in male and female mice. Moreover, repeated coadministration of cenicriviroc with morphine delays the development of opioid tolerance, while the best and longest-lasting analgesic effect is achieved by repeated administration of cenicriviroc alone, which reduces pain hypersensitivity in STZ-exposed mice, and unlike morphine, no tolerance to the analgesic effects of CVC is observed until Day 15 of treatment. Based on these results, we suggest that targeting CCR2 and CCR5 with CVC is a potent therapeutic option for novel pain treatments in diabetic neuropathy patients.

Bioactive alkaloidal and phenolic phytochemicals as promising epidrugs for diabetes mellitus 2: A review of recent development

Type 2 diabetes (T2D) remains a major chronic metabolic disorder affecting hundreds of millions of the global population, mostly among adults, engendering high rates of morbidity and mortality. It is characterized by complex aetiologies including insulin deficiency and resistance, and hyperglycemia, and these significantly constitute therapeutic challenges. Several pathways have been implicated in its pathophysiology and treatment including the epigenetic regulatory mechanism, notably, deoxyribonucleic acid (DNA) methylation/demethylation, histone modification, non-coding ribonucleic acid (ncRNA) modulation and other relevant pathways. Many studies have recently documented the implications of phytochemicals on the aforementioned biomarkers in the pathogenesis and treatment of T2D. In this review, the cellular and molecular mechanisms of the epigenetic effects of some bioactive alkaloidal and phenolic phytochemicals as potential therapeutic alternatives for T2D have been overviewed from the recent literature (2019-2024). From the survey, the natural product-based compounds, C1-C32 were curated as potent epigenetic modulators for T2D. Their cellular and molecular mechanisms of anti-T2D activities with relevant epigenetic biomarkers were revealed. Although, more comprehensive experimental analyses are observably required for validating their activity and toxicological indices. Thus, perspectives and challenges were enumerated for such demanding future translational studies. The review reveals advances in scientific efforts towards reversing the global trend of T2D through epigenetic phytotherapeutics.

The efficacy and safety of Chinese herbal medicine as an add-on therapy for type 2 diabetes mellitus patients with carotid atherosclerosis: An updated meta-analysis of 27 randomized controlled trials

Background: Type 2 diabetes mellitus (T2DM) is a clinical metabolic syndrome characterized by persistent hyperglycemia. Patients with T2DM are more likely to have carotid atherosclerosis (CAS), which can lead to dizziness, amaurosis or even stroke. Chinese herbal medicine (CHM) has shown possible efficacy and safety in treating T2DM patients with CAS. However, the existing evidence was not robust enough and the results were out of date. Objective: This meta-analysis aimed to summarize the current evidence and systematically evaluate the effects of CHM on carotid plaque, glucose and lipid metabolism and vascular endothelial parameters in T2DM patients with CAS, providing a reference for subsequent research and clinical practice. Methods: This study was registered in PROSPERO as CRD42022346274. Both Chinese and English databases were searched from their inceptions to 16 July 2022. All retrieved studies were screened according to inclusion and exclusion criteria. Randomized controlled trials (RCTs) using oral CHM to treat T2DM patients with CAS were included. The literature quality was assessed using the risk of bias assessment tool in the Cochrane Handbook. Data extraction was conducted on the selected studies. Review Manager 5.4 and Stata 16.0 were used for meta-analysis. Sources of heterogeneity were explored by meta-regression or subgroup analysis. Funnel plot and Egger's test were used to assess publication bias and the evidence quality was assessed by Grading of Recommendations Assessment, Development and Evaluation (GRADE). Results: 27 eligible studies, involving 2638 patients, were included in this study. Compared with western medicine (WM) alone, the addition of CHM was significantly better in improving carotid intima-media thickness (CIMT) [mean difference (MD) = -0.11mm, 95% confidence interval (CI): -0.15 to -0.07, p < 0.01], carotid plaque Crouse score [MD = -1.21, 95%CI: -1.35 to -1.07, p < 0.01], total cholesterol (TC) [MD = -0.34 mmol/L, 95%CI: -0.54 to -0.14, p < 0.01], triglyceride (TG) [MD = -0.26 mmol/L, 95%CI: -0.37 to -0.15, p < 0.01], low-density lipoprotein cholesterol (LDL-C) [MD = -0.36 mmol/L, 95%CI: -0.47 to -0.25, p < 0.01], high-density lipoprotein cholesterol (HDL-C) [MD = 0.22 mmol/L, 95%CI: 0.13 to 0.30, p < 0.01], glycated hemoglobin (HbA1c) [MD = -0.36%, 95%CI: -0.51 to -0.21, p < 0.01], fasting blood glucose (FBG) [MD = -0.33 mmol/L, 95%CI: -0.50 to -0.16, p < 0.01], 2-h postprandial glucose (2hPG) [MD = -0.52 mmol/L, 95%CI: -0.95 to -0.09, p < 0.01], homeostasis model assessment of insulin resistance (HOMA-IR) [standardized mean difference (SMD) = -0.88, 95%CI: -1.36 to -0.41, p < 0.01] and homeostasis model assessment of beta-cell function (HOMA-β) [MD = 0.80, 95%CI: 0.51 to 1.09, p < 0.01]. Due to the small number of included studies, it is unclear whether CHM has an improving effect on nitric oxide (NO), endothelin-1 (ET-1), peak systolic velocity (PSV) and resistance index (RI). No serious adverse events were observed. Conclusion: Based on this meta-analysis, we found that in the treatment of T2DM patients with CAS, combined with CHM may have more advantages than WM alone, which can further reduce CIMT and carotid plaque Crouse score, regulate glucose and lipid metabolism, improve insulin resistance and enhance islet β-cell function. Meanwhile, CHM is relatively safe. However, limited by the quality and heterogeneity of included studies, the efficacy and safety of CHM remain uncertain. More high-quality studies are still needed to provide more reliable evidence for the clinical application of CHM. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022346274.

Inflammation triggered by the NLRP3 inflammasome is a critical driver of diabetic bladder dysfunction

Diabetes is a rapidly expanding epidemic projected to affect as many as 1 in 3 Americans by 2050. This disease is characterized by devastating complications brought about high glucose and metabolic derangement. The most common of these complications is diabetic bladder dysfunction (DBD) and estimates suggest that 50-80% of patients experience this disorder. Unfortunately, the Epidemiology of Diabetes Interventions and Complications Study suggests that strict glucose control does not decrease ones risk for incontinence, although it does decrease the risk of other complications such as retinopathy, nephropathy and neuropathy. Thus, there is a significant unmet need to better understand DBD in order to develop targeted therapies to alleviate patient suffering. Recently, the research community has come to understand that diabetes produces a systemic state of low-level inflammation known as meta-inflammation and attention has focused on a role for the sterile inflammation-inducing structure known as the NLRP3 inflammasome. In this review, we will examine the evidence that NLRP3 plays a central role in inducing DBD and driving its progression towards an underactive phenotype.