Metformin: evidence from preclinical and clinical studies for potential novel applications in cardiovascular disease

Development of novel osteoarthritis therapy by targeting AMPK-β-catenin-Runx2 signaling

Osteoarthritis (OA) is a debilitating chronic joint disease affecting large populations of patients, especially the elderly. The pathological mechanisms of OA are currently unknown. Multiple risk factors are involved in OA development. Among these risk factors, alterations of mechanical loading in the joint leading to changes in biological signaling pathways have been known as a key event in OA development. The importance of AMPK-β-catenin-Runx2 signaling in the initiation and progression of OA has been recognized in recent years. In this review, we discuss the recent progress in understanding the role of this signaling pathway and the underlying interaction mechanisms during OA development. We also discuss the drug development aiming to target this signaling pathway for OA treatment.

Protective effect of metformin on the NG-nitro-l-arginine methyl ester (l-NAME)-induced rat models of preeclampsia

BACKGROUND

Preeclampsia (PE) is a complex multi-organ disorder characterized by systemic inflammation, endothelial dysfunction, and vasoconstriction, which manifests as hypertension, with or without proteinuria. Effective preventive strategies for PE are currently lacking in clinical practice, leading to significant morbidity and mortality among mothers and newborns.

OBJECTIVE

This study aims to investigate the impact of metformin (MET) on the l-NAME-induced PE rat model, focusing on the mechanisms through which MET may exert its effects.

METHODS

Thirty pregnant Sprague-Dawley (SD) rats were randomly assigned to three groups: Control, PE, and PE + MET, on gestational day 0 (GD0). Regularly measure blood pressure and 24-h proteinuria, and collect tissue samples on GD20. Enzyme-linked immunosorbent assay (ELISA) was used to analyze inflammatory factors, endothelial function biomarkers, angiogenic factors, and apoptosis-related factors in the rat plasma. Western blot, RT-qPCR, and immunohistochemistry techniques were employed to determine the expression levels of key apoptotic proteins in placental tissue.

RESULTS

The study findings demonstrate that MET administration improves blood pressure and 24-h proteinuria, alleviates fetal growth restriction, ameliorate inflammation cytokines, and restores the balance of angiogenic factors and endothelial function. Moreover, MET inhibits the expression levels of critical apoptotic proteins in the plasma and placental tissue of PE-like rats.

CONCLUSION

The results suggest that MET shows promise in alleviating symptoms associated with l-NAME-induced PE in rats, preserving endothelial function, enhancing angiogenesis, reducing inflammation, inhibiting placental apoptosis, improving placental function, and promoting fetal growth. These findings highlight MET as a potential therapeutic agent for the prevention and treatment of preeclampsia.

Revolutionary drug repositioning: the preventive and therapeutic potential of metformin and other antidiabetic drugs in age-related macular degeneration

Age-related macular degeneration (AMD) is a leading cause of blindness among the elderly worldwide. Anti-vascular endothelial growth factor (anti-VEGF) injections remain the first-line therapy for AMD. However, their high cost and the need for frequent administration pose challenges to long-term adherence, highlighting the need for accessible and cost-effective preventive strategies. Emerging evidence suggests that traditional antidiabetic drugs, such as metformin, sulfonylureas, and thiazolidinediones, may offer neuroprotective benefits, opening new avenues for AMD prevention. Among these, metformin has emerged as the most promising candidate, demonstrating significant potential in reducing AMD risk, even at low cumulative doses, primarily through AMP-activated protein kinase (AMPK) activation. Sulfonylureas, although effective in stimulating insulin secretion, carry risks such as hypoglycemia, hyperinsulinemia, and a possible association with increased cancer risk. Similarly, thiazolidinediones, while improving insulin sensitivity, are associated with adverse effects, including cardiovascular risks and macular edema, limiting their broader application in AMD prevention. This paper explores the preventive potential and underlying mechanisms of these antidiabetic drugs in AMD and discusses the role of artificial intelligence in optimizing individualized prevention strategies. By advancing precision medicine, these approaches may improve public health outcomes and reduce the burden of aging-related vision loss.

Overexpression of miR-199b-5p in Colony Forming Unit-Hill's Colonies Positively Mediates the Inflammatory Response in Subclinical Cardiovascular Disease Model: Metformin Therapy Attenuates Its Expression

Well-controlled type 1 diabetes (T1DM) is characterized by inflammation and endothelial dysfunction, thus constituting a suitable model of subclinical cardiovascular disease (CVD). miR-199b-5p overexpression in murine CVD has shown proatherosclerotic effects. We hypothesized that miR-199b-5p would be overexpressed in subclinical CVD yet downregulated following metformin therapy. Inflammatory and vascular markers were measured in 29 individuals with T1DM and 20 matched healthy controls (HCs). miR-199b-5p expression in CFU-Hill's colonies was analyzed from each study group, and correlations with inflammatory/vascular health indices were evaluated. Significant upregulation of miR-199b-5p was observed in T1DM, which was significantly downregulated by metformin. miR-199b-5p correlated positively with vascular endothelial growth factor-D and c-reactive protein (CRP: nonsignificant). ROC analysis determined miR-199b-5p to define subclinical CVD by discriminating between HCs and T1DM individuals. ROC analyses of HbA1c and CRP showed that the upregulation of miR-199b-5p in T1DM individuals defined subclinical CVD at HbA1c > 44.25 mmol and CRP > 4.35 × 106 pg/mL. Ingenuity pathway analysis predicted miR-199b-5p to inhibit the target genes SIRT1, ETS1, and JAG1. Metformin was predicted to downregulate miR-199b-5p via NFATC2 and STAT3 and reverse its downstream effects. This study validated the antiangiogenic properties of miR-199b-5p and substantiated miR-199b-5p overexpression as a biomarker of subclinical CVD. The downregulation of miR-199b-5p by metformin confirmed its cardio-protective effect.

Metformin Monotherapy With and Without Lifestyle Changes Affects Anthropometric Parameters, Blood Pressure, Blood Glucose, and Lipid Profile in Indian Patients With Newly Diagnosed Type 2 Diabetes

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a consequence of insulin resistance, insulin deficiency, or both. It is usually seen in adults and is a consequence of genetic (polygenic inheritance), endogenous (obesity and or hormonal factors), and environmental factors (e.g., obesogenic environment, endocrine disrupting chemicals, stress, and medicines). The prevalence of T2DM has increased over the past few decades. South Asians, including Indians, are more prone to central adiposity and develop lifestyle diseases like T2DM at body mass index values lower than those considered normal for the Western population. Generally, the first line of treatment is metformin monotherapy with lifestyle changes in patients with T2DM. Most of the research conducted on this drug is on Western subjects. Since the Indian population has genetic differences in the site of deposition of adipose and is more prone to develop lifestyle diseases, the effect of metformin may be different in Indians.

METHODS

Seventy-one (34 female, non-pregnant, non-lactating) adults with newly diagnosed T2DM were recruited in this short-duration pilot study after obtaining written informed consent. Patients regularly taking any drug were excluded, as were patients with chronic comorbidities. Treatment was initiated with metformin 500 mg OD. Lifestyle changes were recommended according to the age and physical condition of the patients. Anthropometric parameters (age, weight, height, BMI, waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR)), blood pressure, glycemic status (fasting and 2 h PP glucose and HbA1c), and lipid profile of the subjects were recorded before initiating and six months after initiating metformin monotherapy with lifestyle changes.

RESULTS

Small but statistically significant improvements were observed in the WHR,WHtR, blood pressure, blood glucose, and glycated hemoglobin. Although improvement was also observed in weight and lipid profile, these changes were not statistically significant.

CONCLUSION

This study shows that metformin monotherapy with lifestyle changes is suitable for patients of Indian origin and results in improvement in the WHR, WHtR, blood pressure, plasma glucose, and glycated hemoglobin.

Unraveling genetic causality between metformin and myocardial infarction on the basis of Mendelian randomization

Background

In recent years, several studies have explored the effect of metformin on myocardial infarction (MI), but whether metformin has an improvement effect in patients with MI is controversial. This study was aimed to investigate the causal relationship between metformin and MI using Mendelian randomization (MR) analysis.

Methods

The genome-wide significant (P<5×10-8) single-nucleotide polymorphisms (SNPs) in patients with metformin and patients with MI were screened from the Open genome-wide association study (GWAS) project as instrumental variables (IVs). The study outcomes mainly included MI, old MI, acute MI, acute transmural MI of inferior wall, and acute transmural MI of anterior wall. The inverse variance weighted (IVW) method was applied to assess the main causal effect, and weighted median, simple mode, weighted mode methods, and MR-Egger regression were auxiliary applied for supplementary proof. The causal relationship between metformin and MI was assessed using odds ratios (OR) and 95% confidence intervals (95% CI). A leave-one-out method was used to explore the effect of individual SNPs on the results of IVW analyses, and a funnel plot was used to analyze the potential bias of the study results, thus ensuring the robustness of the results.

Results

In total, 16, 84, 39, 26, and 34 SNPs were selected as IVs to assess the genetic association between metformin and outcomes of MI, old MI, acute MI, acute transmural MI of inferior wall, and acute transmural MI of anterior wall, respectively. Treatment with metformin does not affect the risk of acute transmural MI of anterior wall at the genetic level (P>0.05; OR for inverse variance weighted was 1.010). In the cases of MI, old MI, acute MI, and acute transmural MI of inferior wall, metformin may even be a risk factor for patients (P<0.05; ORs for inverse variance weighted were 1.078, 1.026, 1.022 and 1.018 respectively). There was no horizontal pleiotropy or heterogeneity among IVs. The results were stable when removing the SNPs one by one.

Conclusion

Metformin is not protective against the risk of myocardial infarction in patients and may even be a risk factor for MI, old MI, acute MI, and acute transmural MI of inferior wall.

Biotherapeutic approaches against cardio-metabolic dysfunctions based on extracellular vesicles

Among the different pathways involved in the cell-to-cell communication, extracellular vesicles (EVs) are defined as key players in the transport of different signalling molecules, such as lipids, proteins, and RNA, from the originating cells to specific target cells. The biogenesis and composition of EVs are complex and confer them a unique ability to more effectively reach tissues and cells as compared to other types of synthetic carriers. Owing to these properties, EVs have been suggested as new therapeutic tools for personalized medicine. Since cardiometabolic diseases have reached pandemic proportions, new therapies are needed to be developed. In this context, EVs appear as promising therapeutic tools against cardiometabolic disorders associated with obesity and diabetes. This review focuses on the latest research on preclinical applications of EVs for cardiometabolic diseases, and draw primarily on our experience in this area.

Potential Geroprotectors - From Bench to Clinic

Geroprotectors are substances that slow down aging process and can be used for prevention of age-related diseases. Geroprotectors can improve functioning of various organ systems and enhance their homeostatic capabilities. We have developed a system of criteria for geroprotectors and proposed their classification based on the mechanisms of their action on the aging processes. Geroprotectors are required to reduce mortality, improve human aging biomarkers, have minimal side effects, and enhance quality of life. Additionally, there are approaches based on combining geroprotectors targeted to different targets and mechanisms of aging to achieve maximum effectiveness. Currently, numerous preclinical studies are being conducted to identify new molecular targets and develop new approaches to extend healthy aging, although the number of clinical trials is limited. Geroprotectors have the potential to become a new class of preventive medicines as they prevent onset of certain diseases or slow down their progression.