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Nature Reviews. Endocrinology Aug 2023Currently, metformin is the first-line medication to treat type 2 diabetes mellitus (T2DM) in most guidelines and is used daily by >200 million patients. Surprisingly,... (Review)
Review
Currently, metformin is the first-line medication to treat type 2 diabetes mellitus (T2DM) in most guidelines and is used daily by >200 million patients. Surprisingly, the mechanisms underlying its therapeutic action are complex and are still not fully understood. Early evidence highlighted the liver as the major organ involved in the effect of metformin on reducing blood levels of glucose. However, increasing evidence points towards other sites of action that might also have an important role, including the gastrointestinal tract, the gut microbial communities and the tissue-resident immune cells. At the molecular level, it seems that the mechanisms of action vary depending on the dose of metformin used and duration of treatment. Initial studies have shown that metformin targets hepatic mitochondria; however, the identification of a novel target at low concentrations of metformin at the lysosome surface might reveal a new mechanism of action. Based on the efficacy and safety records in T2DM, attention has been given to the repurposing of metformin as part of adjunct therapy for the treatment of cancer, age-related diseases, inflammatory diseases and COVID-19. In this Review, we highlight the latest advances in our understanding of the mechanisms of action of metformin and discuss potential emerging novel therapeutic uses.
Topics: Humans; Metformin; Diabetes Mellitus, Type 2; Hypoglycemic Agents; COVID-19; Glucose
PubMed: 37130947
DOI: 10.1038/s41574-023-00833-4 -
JAMA May 2019Metformin is the first-line pharmacologic treatment for type 2 diabetes and the most commonly prescribed drug for this condition worldwide, either alone or in... (Review)
Review
Metformin is the first-line pharmacologic treatment for type 2 diabetes and the most commonly prescribed drug for this condition worldwide, either alone or in combination with insulin or other glucose-lowering therapies. Metformin is a biguanide, a drug class of herbal origin that has been widely used to treat diabetes since the 1950s. Two other biguanides were withdrawn from clinical use because they caused lactic acidosis. Metformin was also taken off the US market due to concerns over lactic acidosis, but it subsequently has been proven safe and effective in lowering glucose levels and was reintroduced in 1995. Optimal metformin use requires clear understanding of its effects, dosing, safety, and alternatives.
Topics: Contraindications, Drug; Diabetes Mellitus, Type 2; Humans; Hypoglycemic Agents; Metformin; Practice Guidelines as Topic
PubMed: 31009043
DOI: 10.1001/jama.2019.3805 -
Frontiers in Endocrinology 2021The numerous beneficial health outcomes associated with the use of metformin to treat patients with type 2 diabetes (T2DM), together with data from pre-clinical studies... (Review)
Review
The numerous beneficial health outcomes associated with the use of metformin to treat patients with type 2 diabetes (T2DM), together with data from pre-clinical studies in animals including the nematode, C. elegans, and mice have prompted investigations into whether metformin has therapeutic utility as an anti-aging drug that may also extend lifespan. Indeed, clinical trials, including the MILES (Metformin In Longevity Study) and TAME (Targeting Aging with Metformin), have been designed to assess the potential benefits of metformin as an anti-aging drug. Preliminary analysis of results from MILES indicate that metformin may induce anti-aging transcriptional changes; however it remains controversial as to whether metformin is protective in those subjects free of disease. Furthermore, despite clinical use for over 60 years as an anti-diabetic drug, the cellular mechanisms by which metformin exerts either its actions remain unclear. In this review, we have critically evaluated the literature that has investigated the effects of metformin on aging, healthspan and lifespan in humans as well as other species. In preparing this review, particular attention has been placed on the strength and reproducibility of data and quality of the study protocols with respect to the pharmacokinetic and pharmacodynamic properties of metformin. We conclude that despite data in support of anti-aging benefits, the evidence that metformin increases lifespan remains controversial. However, its ability to reduce early mortality associated with various diseases, including diabetes, cardiovascular disease, cognitive decline and cancer, metformin can improve healthspan thereby extending the period of life spent in good health. Based on the available evidence we conclude that the beneficial effects of metformin on aging and healthspan are primarily indirect its effects on cellular metabolism and result from its anti-hyperglycemic action, enhancing insulin sensitivity, reduction of oxidative stress and protective effects on the endothelium and vascular function.
Topics: Aging; Animals; Caenorhabditis elegans; Diabetes Mellitus, Type 2; Humans; Longevity; Metformin; Mice; Oxidative Stress
PubMed: 34421827
DOI: 10.3389/fendo.2021.718942 -
Theranostics 2022Aging is a natural process, which plays a critical role in the pathogenesis of a variety of diseases, i.e., aging-related diseases, such as diabetes, osteoarthritis,... (Review)
Review
Aging is a natural process, which plays a critical role in the pathogenesis of a variety of diseases, i.e., aging-related diseases, such as diabetes, osteoarthritis, Alzheimer disease, cardiovascular diseases, cancers, obesity and other metabolic abnormalities. Metformin, the most widely used antidiabetic drug, has been reported to delay aging and display protective effect on attenuating progression of various aging-related diseases by impacting key hallmark events of aging, including dysregulated nutrient sensing, loss of proteostasis, mitochondrial dysfunction, altered intercellular communication, telomere attrition, genomic instability, epigenetic alterations, stem cell exhaustion and cellular senescence. In this review, we provide updated information and knowledge on applications of metformin in prevention and treatment of aging and aging-related diseases. We focus our discussions on the roles and underlying mechanisms of metformin in modulating aging and treating aging-related diseases.
Topics: Aging; Cellular Senescence; Genomic Instability; Humans; Metformin; Telomere
PubMed: 35401820
DOI: 10.7150/thno.71360 -
Cell Metabolism Feb 2024Here, we summarize the current knowledge on eight promising drugs and natural compounds that have been tested in the clinic: metformin, NAD precursors, glucagon-like... (Review)
Review
Here, we summarize the current knowledge on eight promising drugs and natural compounds that have been tested in the clinic: metformin, NAD precursors, glucagon-like peptide-1 receptor agonists, TORC1 inhibitors, spermidine, senolytics, probiotics, and anti-inflammatories. Multiple clinical trials have commenced to evaluate the efficacy of such agents against age-associated diseases including diabetes, cardiovascular disease, cancer, and neurodegenerative diseases. There are reasonable expectations that drugs able to decelerate or reverse aging processes will also exert broad disease-preventing or -attenuating effects. Hence, the outcome of past, ongoing, and future disease-specific trials may pave the way to the development of new anti-aging medicines. Drugs approved for specific disease indications may subsequently be repurposed for the treatment of organism-wide aging consequences.
Topics: Humans; NAD; Aging; Metformin; Cardiovascular Diseases; Neoplasms
PubMed: 38181790
DOI: 10.1016/j.cmet.2023.12.007 -
Drugs Jul 2015People with elevated, non-diabetic, levels of blood glucose are at risk of progressing to clinical type 2 diabetes and are commonly termed 'prediabetic'. The term... (Review)
Review
People with elevated, non-diabetic, levels of blood glucose are at risk of progressing to clinical type 2 diabetes and are commonly termed 'prediabetic'. The term prediabetes usually refers to high-normal fasting plasma glucose (impaired fasting glucose) and/or plasma glucose 2 h following a 75 g oral glucose tolerance test (impaired glucose tolerance). Current US guidelines consider high-normal HbA1c to also represent a prediabetic state. Individuals with prediabetic levels of dysglycaemia are already at elevated risk of damage to the microvasculature and macrovasculature, resembling the long-term complications of diabetes. Halting or reversing the progressive decline in insulin sensitivity and β-cell function holds the key to achieving prevention of type 2 diabetes in at-risk subjects. Lifestyle interventions aimed at inducing weight loss, pharmacologic treatments (metformin, thiazolidinediones, acarbose, basal insulin and drugs for weight loss) and bariatric surgery have all been shown to reduce the risk of progression to type 2 diabetes in prediabetic subjects. However, lifestyle interventions are difficult for patients to maintain and the weight loss achieved tends to be regained over time. Metformin enhances the action of insulin in liver and skeletal muscle, and its efficacy for delaying or preventing the onset of diabetes has been proven in large, well-designed, randomised trials, such as the Diabetes Prevention Program and other studies. Decades of clinical use have demonstrated that metformin is generally well-tolerated and safe. We have reviewed in detail the evidence base supporting the therapeutic use of metformin for diabetes prevention.
Topics: Diabetes Mellitus, Type 2; Humans; Hypoglycemic Agents; Metformin; Prediabetic State
PubMed: 26059289
DOI: 10.1007/s40265-015-0416-8 -
Biomedicine & Pharmacotherapy =... May 2021Metformin is the first-line option for treating newly diagnosed diabetic patients and also involved in other pharmacological actions, including antitumor effect,... (Review)
Review
Metformin is the first-line option for treating newly diagnosed diabetic patients and also involved in other pharmacological actions, including antitumor effect, anti-aging effect, polycystic ovarian syndrome prevention, cardiovascular action, and neuroprotective effect, etc. However, the mechanisms of metformin actions were not fully illuminated. Recently, increasing researches showed that autophagy is a vital medium of metformin playing pharmacological actions. Nevertheless, results on the effects of metformin on autophagy were inconsistent. Apart from few clinical evidences, more data focused on kinds of no-clinical models. First, many studies showed that metformin could induce autophagy via a number of signaling pathways, including AMPK-related signaling pathways (e.g. AMPK/mTOR, AMPK/CEBPD, MiTF/TFE, AMPK/ULK1, and AMPK/miR-221), Redd1/mTOR, STAT, SIRT, Na/H exchangers, MAPK/ERK, PK2/PKR/AKT/ GSK3β, and TRIB3. Secondly, some signaling pathways were involved in the process of metformin inhibiting autophagy, such as AMPK-related signaling pathways (AMPK/NF-κB and other undetermined AMPK-related signaling pathways), Hedgehog, miR-570-3p, miR-142-3p, and MiR-3127-5p. Thirdly, two types of signaling pathways including PI3K/AKT/mTOR and endoplasmic reticulum (ER) stress could bidirectionally impact the effectiveness of metformin on autophagy. Finally, multiple signal pathways were reviewed collectively in terms of affecting the effectiveness of metformin on autophagy. The pharmacological effects of metformin combining its actions on autophagy were also discussed. It would help better apply metformin to treat diseases in term of mediating autophagy.
Topics: Animals; Autophagy; Autophagy-Related Proteins; Humans; Hypoglycemic Agents; Metformin; Signal Transduction
PubMed: 33524789
DOI: 10.1016/j.biopha.2021.111286 -
Journal of Translational Medicine Jun 2023Metformin is a well-known anti-diabetic drug that has been repurposed for several emerging applications, including as an anti-cancer agent. It boasts the distinct... (Review)
Review
Metformin is a well-known anti-diabetic drug that has been repurposed for several emerging applications, including as an anti-cancer agent. It boasts the distinct advantages of an excellent safety and tolerability profile and high cost-effectiveness at less than one US dollar per daily dose. Epidemiological evidence reveals that metformin reduces the risk of cancer and decreases cancer-related mortality in patients with diabetes; however, the exact mechanisms are not well understood. Energy metabolism may be central to the mechanism of action. Based on altering whole-body energy metabolism or cellular state, metformin's modes of action can be divided into two broad, non-mutually exclusive categories: "direct effects", which induce a direct effect on cancer cells, independent of blood glucose and insulin levels, and "indirect effects" that arise from systemic metabolic changes depending on blood glucose and insulin levels. In this review, we summarize an updated account of the current knowledge on metformin antitumor action, elaborate on the underlying mechanisms in terms of the hallmarks of cancer, and propose potential applications for repurposing metformin for cancer therapeutics.
Topics: Humans; Metformin; Blood Glucose; Drug Repositioning; Neoplasms; Insulins; Hypoglycemic Agents; Diabetes Mellitus, Type 2
PubMed: 37344841
DOI: 10.1186/s12967-023-04263-8 -
The Lancet. Diabetes & Endocrinology Apr 2023Tackling the mechanisms underlying ageing is desirable to help to extend the duration and improve the quality of life. Life extension has been achieved in animal models... (Review)
Review
Tackling the mechanisms underlying ageing is desirable to help to extend the duration and improve the quality of life. Life extension has been achieved in animal models by suppressing the growth hormone-insulin-like growth factor 1 (IGF-1) axis and also via dietary restriction. Metformin has become the focus of increased interest as a possible anti-ageing drug. There is some overlap in the postulated mechanisms of how these three approaches could produce anti-ageing effects, with convergence on common downstream pathways. In this Review, we draw on evidence from both animal models and human studies to assess the effects of suppression of the growth hormone-IGF-1 axis, dietary restriction, and metformin on ageing.
Topics: Animals; Humans; Growth Hormone; Insulin-Like Growth Factor I; Metformin; Quality of Life; Aging; Human Growth Hormone
PubMed: 36848915
DOI: 10.1016/S2213-8587(23)00001-3 -
Annals of Oncology : Official Journal... Dec 2016Metformin use has been associated with a reduced risk of developing cancer and an improvement in overall cancer survival rates in meta-analyses, but, to date, evidence... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Metformin use has been associated with a reduced risk of developing cancer and an improvement in overall cancer survival rates in meta-analyses, but, to date, evidence to support the use of metformin as an adjuvant therapy in individual cancer types has not been presented.
PATIENTS AND METHODS
We systematically searched research databases, conference abstracts and trial registries for any studies reporting cancer outcomes for individual tumour types in metformin users compared with non-users, and extracted data on patients with early-stage cancer. Studies were assessed for design and quality, and a meta-analysis was conducted to quantify the adjuvant effect of metformin on recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS), to inform future trial design.
RESULTS
Of 7670 articles screened, 27 eligible studies were identified comprising 24 178 participants, all enrolled in observational studies. In those with early-stage colorectal cancer, metformin use was associated with a significant benefit in all outcomes [RFS hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.47-0.85; OS HR 0.69, CI 0.58-0.83; CSS HR 0.58, CI 0.39-0.86]. For men with early-stage prostate cancer, metformin was associated with significant, or borderline significant, benefits in all outcomes (RFS HR 0.83, CI 0.69-1.00; OS HR 0.82, CI 0.73-0.93; CSS HR 0.58, CI 0.37-0.93); however, there was significant heterogeneity between studies. The data suggest that prostate cancer patients treated with radical radiotherapy may benefit more from metformin (RFS HR 0.45, CI 0.29-0.70). In breast and urothelial cancer, no significant benefits were identified. Sufficient data were not available to conduct analyses on the impact of metformin dose and duration.
CONCLUSIONS
Our findings suggest that metformin could be a useful adjuvant agent, with the greatest benefits seen in colorectal and prostate cancer, particularly in those receiving radical radiotherapy, and randomised, controlled trials which investigate dose and duration, alongside efficacy, are advocated.
Topics: Chemotherapy, Adjuvant; Disease-Free Survival; Humans; Metformin; Neoplasm Staging; Neoplasms
PubMed: 27681864
DOI: 10.1093/annonc/mdw410