Mitochondria as an important target of metformin: The mechanism of action, toxic and side effects, and new therapeutic applications

Enhancing PD-1 blockade in NSCLC: Reprogramming tumor immune microenvironment with albumin-bound statins targeting lipid rafts and mitochondrial respiration

Non-small cell lung cancer (NSCLC) has shown limited response to immunotherapy, primarily due to an immunosuppressive tumor microenvironment characterized by hypoxia and lipid raft formation, which together inhibit T-cell infiltration and function, impeding effective immune responses. To address these challenges, we developed Abstatin, an albumin-bound fluvastatin formulation that targets lipid raft disruption and mitochondrial respiration inhibition, aiming to reduce hypoxia and destabilize lipid rafts to enhance T-cell activity within the tumor. Using bioinformatics analysis, in vitro assays, and in vivo studies in both murine and humanized PDX models, we demonstrated that Abstatin reprograms the NSCLC microenvironment by concurrently lowering hypoxia levels and lipid raft integrity, thereby restoring T-cell infiltration, enhancing cytotoxic T-cell function, and ultimately improving response to Anti-PD-1 therapy. Results showed that Abstatin significantly amplifies Anti-PD-1 efficacy with minimal toxicity, indicating a favorable safety profile for clinical use. This study highlights Abstatin as a promising immunotherapy adjuvant that addresses critical barriers in NSCLC by modulating metabolic pathways linked to immune resistance. Abstatin's approach, which combines modulation of cellular metabolism with immune sensitization, broadens the potential of immunotherapy and provides a practical, scalable strategy to enhance treatment outcomes in NSCLC and potentially other tumors, offering insights into combinatory cancer therapies.

Long-term effects of metformin on offspring health: A review of current evidence and future directions

Metformin is widely prescribed for the management of type 2 diabetes mellitus, polycystic ovary syndrome, and gestational diabetes mellitus in pregnancy. Its use is driven by factors including oral administration, lower patient and health system burden and cost, and benefits including lower risk of excess gestational weight gain and hypoglycemia compared with insulin. Metformin use appears safe in pregnancy; however, there remain concerns regarding long-term effects of intrauterine metformin exposure on offspring health. Randomized controlled trial follow-up studies suggest that metformin-exposed offspring may have altered postnatal growth trajectories and increased adiposity in childhood, although data are limited. Whether this is a transient adaptation or a precursor to long-term metabolic dysfunction is unclear, as data on cardiometabolic and neurodevelopmental parameters, including glucose homeostasis, lipid metabolism, and cognitive function, are sparse and inconsistent. Methodological challenges include heterogeneous study designs, high attrition rates, and inadequate control for confounding variables. Given these uncertainties, further well-powered, long-term prospective studies and individual patient data meta-analyses, harmonizing data and adjusting for confounders, are needed to clarify risks and benefits of metformin use in pregnancy. Until such data are available, clinicians must weigh the benefits and advantages of metformin use in pregnancy against the unknowns regarding potential long-term impact on offspring health. PLAIN LANGUAGE SUMMARY: Metformin is a medicine often used during pregnancy to help manage conditions such as type 2 diabetes, gestational diabetes, and polycystic ovary syndrome (PCOS). It is commonly chosen because it is taken as a tablet rather than by injection, has a lower risk of causing low blood sugar, and is generally easier and less expensive to use than insulin. Research has shown that metformin is safe for use during pregnancy in the short term. However, there are still questions about whether it has any lasting effects on children who were exposed to it before birth. This review explores this topic in detail. Some studies have found that children exposed to metformin during pregnancy may have slightly different growth patterns, such as having more body fat or being heavier in early childhood. However, these results are inconsistent and most studies show no clear differences in overall health outcomes, including in heart health, metabolism, or brain development. The results are mixed, and many studies are small or have design limitations, which makes it difficult to draw strong conclusions. At this stage, there is no clear evidence that metformin causes harm to children in the long term. However, because some studies suggest there may be effects on childhood growth and development, researchers emphasize the need for further long-term research. These future studies should follow children into adolescence and adulthood to better understand any lasting impacts. Until more is known, doctors and patients will need to carefully consider the known benefits of metformin in pregnancy alongside the current uncertainties about long-term effects on child health.

A meta-analysis on application and prospect of cell therapy in the treatment of diabetes mellitus

OBJECTIVE

Diabetes mellitus (DM) is a grave autoimmune disorder because of no insulin self-generation. Currently, mainly clinical methods exist, serious adverse effects leading to stem cell therapy are considered. The mesenchymal stem cells (MSCs), require high differentiation capacity and are judged as crucial in DM treatment. The meta-analysis aimed to systemically analyze the particular types of MSCs which play a more important role in DM and which DM is treated more effectively.

METHOD

A systematic review was conducted on the published literature, clinical trials and observational studies, utilizing databases such as PubMed, Embase, Cochrane and clinicaltrial.gov. RevMan software was adopted to draw Forest Plot and Funnel Plot, and subgroup analysis were employed to evaluate heterogeneity between different groups.

RESULTS

We identified the meta-analyses of 34 unique random controlled trials and divided our own systematic reviews into 8 groups. The MSCs were associated with placebo (OR = 2.79, 95% CI [1.63, 4.75]), Standard Clinical Treatment (SCT) (OR = 4.12, 95% CI [2.76, 6.14]), and monocyte (OR = 6.52, 95% CI [3.56, 9.48]). The comparison between Autologous MSCs and Allogenic MSCs (OR = 4.64, 95% CI [3.42, 6.31]), Autologous BMMSCs and other MSCs (OR = 5.28, 95% CI [3.64, 7.66]), Allogenic ASCs and UCMSCs (OR = 3.54, 95% CI [1.83, 6.86]), Type I DM and Type II DM (OR = 3.10, 95% CI [1.79, 5.38]), intravenous injection and other injections (OR = 4.81, 95% CI [3.34, 6.94]), diabetic foot ulcers and diabetic neurological disease (OR = 3.88,,95% CI [2.53,5.95]).

CONCLUSION

Current evidence suggests that MSCs hold significant potential for treating DM, demonstrating considerably high safety and efficacy. MSCs exhibit higher therapeutic benefits compared to monocytes, with autologous MSCs offering better clinical outcomes than allogenic sources. MSCs (BMMSCs) proved more effective than other types of MSCs. However, no significant differences were observed between adipose-derived MSCs (ASCs) and umbilical cord-derived MSCs (UCMSCs) in the allogeneic setting. Moreover, MSCs show more pronounced therapeutic effects in Type II DM, and the difference among the injection methods is minimally observed. In conclusion, the research scope on DM is relatively limited in this study and further research is necessary to improve the reliability of the estimates.

Bioactive fraction isolated from Curcuma angustifolia rhizome exerts anti-diabetic effects in vitro, in silico and in vivo by regulating AMPK/PKA signaling pathway

Curcuma angustifolia Roxb. is a therapeutic herb and a member of the Zingiberaceae family. A potential bioactive fraction was isolated from the methanolic extract of Curcuma angustifolia rhizome using column chromatography, and it was characterised using 1H-NMR, GCMS and FTIR analyses. The bioactive fraction showed no toxic effects on the HepG2 cell line and it demonstrated inhibition of α-amylase and α-glucosidase enzymes in vitro with IC50 values of 2.75 ± 0.09 and 4.9 ± 0.07 µM, respectively. Molecular docking analysis also showed that nerolidol, the major constituent of the bioacive fraction inhibits α-amylase and α-glucosidase enzymes competitively, supporting in vitro antihyperglycemic activity. ADMET analysis showed that nerolidol has the necessary physicochemical parameters for drug-likeness. It also complies with Lipinski's rule, indicating that its chemical structure is appropriate for designing safe and bioavailable oral drug. The antidiabetic efficacy of the isolated bioactive fraction was validated in type 2 diabetic albino wistar rats induced with a high-fat diet and a low dose (35 mg/kg bw) of streptozotocin. After 28 days of intervention, the lower and higher doses of the bioactive fraction (100 and 200 mg/kg BW) substantially decreased fasting blood glucose levels and ameliorated hyperglycemia, glucose intolerance, insulin resistance, and hyperlipidemia. The higher dose of bioactive fraction significantly ameliorated liver, kidney, and lipid profiles compared to the standard drug metformin and exhibited lower toxicity in the liver, kidney, pancreas, and epididymal adipose tissue than the lower dose of the bioactive fraction. Gene expression studies revealed that the bioactive fraction upregulated AMPK through downregulating PKA, a mechanism similar to the action of metformin. The results indicate that the isolated bioactive fraction could be a natural alternative to synthetic antidiabetic medications.

Metformin aggravates pancreatitis by regulating the release of oxidised mitochondrial DNA via the frataxin (FXN)/ninjurin 1 (NINJ1) signalling pathway

BACKGROUND AND PURPOSE

Patients with diabetes are at a higher risk of developing acute pancreatitis compared to those without diabetes. Therefore, it is essential to investigate the effects of metformin, a primary treatment for type 2 diabetes, on the progression of pancreatitis.

EXPERIMENTAL APPROACH

Network pharmacology was employed to investigate the potential effects of metformin on pancreatitis and to predict its underlying molecular mechanisms. Pharmacological and mechanistic studies of metformin were conducted utilising mtDNA depletion (ρ0) of 266-6 acinar cells, knockout mouse models and experimental models of both acute and chronic pancreatitis. The mitochondrial homeostasis and plasma membrane integrity were examined through phase-contrast microscopy and time-lapse video imaging.

KEY RESULTS

Network pharmacology analysis revealed that metformin possesses significant potential to modulate the pathogenesis of pancreatitis, likely through its regulation of mitochondrial function and cell membrane morphology. Further, the results revealed that metformin augmented the release of oxidised mitochondrial DNA (Ox-mtDNA) by enhancing NINJ1-mediated plasma membrane rupture, which subsequently ignited a cascade of acinar cell necrosis. Metformin exacerbated mitochondrial iron imbalance by suppressing Frataxin, thereby worsening mitochondrial homeostasis disruption and Ox-mtDNA generation. NINJ1 knockout eliminated the metformin-induced acinar cell necrosis and elevation of Ox-mtDNA levels, and mtDNA depletion reversed the effect of metformin on acinar cell death.

CONCLUSION AND IMPLICATIONS

Metformin exacerbates both acute and chronic pancreatitis, possibly because of increased release of Ox-mtDNA via modulation of mitochondrial iron homeostasis and NINJ1-mediated plasma membrane rupture, suggesting that extreme caution should be exercised when using metformin in diabetic patients with pancreatitis.

Evaluation of the toxicity potential of exercise and atorvastatin/metformin combination therapy on STZ-diabetic rats

Exercise is recommended for individuals with diabetes, and metformin and atorvastatin are commonly prescribed to diabetic patients. However, these two drugs have potential effects that may lead to toxicity in the skeletal muscle system. Therefore, the effects and potential interactions of combining these two drugs on skeletal muscle performance and structure were investigated in vivo in an experimental diabetes model. Male Wistar rats were divided into six groups: a sedentary control group (N) and five treatment groups-exercise (C), diabetes (D), diabetes with metformin (MET), diabetes with atorvastatin (ATO), and diabetes with metformin and atorvastatin (MET + ATO). In the diabetes model experimentally created with streptozotocin (STZ; 45 mg/kg, i.p.) and metformin (300 mg/kg/day), atorvastatin (10 mg/kg/day) was administered to drug groups by gavage during the 4-week study period. The rats were allowed to run (at moderate level) for 30 min, 5 days a week, on the treadmill. At the end of the study, blood samples and gastrocnemius muscle tissues of the rats were obtained under ketamine anesthesia (100 mg/kg; i.p). The effects of combining exercise and medication on skeletal muscle were assessed by examining the levels of significant biomarkers including PGC-1α, UCP-3, and MyHCs, as well as analyzing oxidative stress/antioxidant capacity parameters in muscle tissue samples. Additionally, relevant biochemical indicators were determined in serum samples. The quantity and morphology of mitochondria in muscle tissue were assessed using transmission electron microscopy. It was observed in the study that some toxic effects associated with the use of drugs alone were reduced by combination therapy. It is thought that this study will contribute to the literature in the evaluation of the effects of drugs and their combined use in Type 1 diabetes under exercise conditions.

Mitochondrial microRNAs (mitomiRs) as emerging biomarkers and therapeutic targets for chronic human diseases

Mitochondria are membrane-bound cell organelles that undertake the majority of the energetic and metabolic processes within the cell. They are also responsible for mediating multiple apoptotic pathways, balancing redox charges, and scavenging reactive oxygen species. MicroRNAs, which are short, non-coding RNAs widely known for regulating gene expression at the post-transcriptional level, regulate many of these processes. The specific microRNAs that directly or indirectly control mitochondrial dynamics are called mitochondrial miRNAs (mitomiRs). The broadest classification of this type of ncRNA encompasses nuclear-encoded miRNAs that interact with cytoplasmatic mRNAs associated with mitochondrial activity. At the same time, a more specific subset comprises nuclear-encoded miRNAs that translocate into the mitochondria to interact with mRNAs inside of this organelle. Finally, the smallest group of mitomiRs includes those codified by mtDNA and can regulate endogenous mitochondrial transcripts or be transported into the cytoplasm to modulate circulating mRNAs. Regardless of the origin or action mechanism, mitomiRs have been recently recognized to have a key role in the progression of a variety of chronic disorders, such as neurodegenerative and cardiovascular diseases, diabetes, asthma, depression, and even cancer. All of these progressive pathologies have been tightly linked to mitochondrial dysregulation. They are further associated with an aberrant expression of specific miRNAs that regulate cellular metabolism, positioning mitomiRs as reliable biomarkers for diagnosing several chronic diseases. These molecular indicators have also provided insights into how these conditions progress, allowing for the development of different miRNA-based treatment strategies that target dysregulated mitochondrial-related genes, reestablishing their baseline activity and restricting further disease progression.

Heterozygous Kmt2d loss diminishes enhancers to render medulloblastoma cells vulnerable to combinatory inhibition of LSD1 and OXPHOS

The histone H3 lysine 4 (H3K4) methyltransferase KMT2D (also called MLL4) is one of the most frequently mutated epigenetic modifiers in many cancers, including medulloblastoma (MB). Notably, heterozygous KMT2D loss frequently occurs in MB and other cancers. However, its oncogenic role remains largely uncharacterized. Here, we show that heterozygous Kmt2d loss in murine cerebellar regions promotes MB genesis driven by heterozygous loss of the MB-suppressor gene Ptch via the upregulation of tumor-promoting programs (e.g., oxidative phosphorylation [OXPHOS]). Downregulation of the transcription-repressive tumor suppressor NCOR2 by heterozygous Kmt2d loss, along with Ptch+/--increased MYCN, upregulated tumor-promoting genes. Heterozygous Kmt2d loss substantially diminished enhancer marks (H3K4me1 and H3K27ac) and the H3K4me3 signature, including those for Ncor2. Combinatory pharmacological inhibition of the enhancer-decommissioning H3K4 demethylase LSD1 and OXPHOS significantly reduced the tumorigenicity of MB cells bearing heterozygous Kmt2d loss. Our findings suggest the molecular and epigenetic pathogenesis underlying the MB-promoting effect of heterozygous KMT2D loss.

Metabolic anomalies in vitiligo: a new frontier for drug repurposing strategies

Vitiligo is a chronic autoimmune condition characterized by the destruction of melanocytes, leading to patchy loss of skin depigmentation. Although its precise cause remains unclear, recent evidence suggests that metabolic disturbances, particularly oxidative stress and mitochondrial dysfunction, may play a significant role in the pathogenesis of the disease. Oxidative stress is thought to damage melanocytes and trigger inflammatory responses, culminating in melanocyte immune-mediate destruction. Additionally, patients with vitiligo often exhibit extra-cutaneous metabolic abnormalities such as abnormal glucose metabolism, dyslipidemia, high fasting plasma glucose levels, high blood pressure, out of range C-peptide and low biological antioxidant capacity, suggesting a potential link between metabolic impairment and vitiligo development. This implies that the loss of functional melanocytes mirrors a more general systemic targetable dysfunction. Notably, therapies targeting metabolic pathways, particularly those involving mitochondrial metabolism, such as the peroxisome proliferator-activated nuclear receptor γ (PPARγ) agonists, are currently being investigated as potential treatments for vitiligo. PPARγ activation restores mitochondrial membrane potential, mitochondrial DNA copy number and, consequently, ATP production. Moreover, PPARγ agonists counteract oxidative stress, reduce inflammation, inhibit apoptosis, and maintain fatty acid metabolism, in addition to the well-known capability to enhance insulin sensitivity. Additionally, increasing evidence of a strong relationship between metabolic alterations and vitiligo pathogenesis suggests a role for other approved anti-diabetic treatments, like metformin and fibrates, in vitiligo treatment. Taken together, these data support the use of approaches alternative to traditional immune-suppressive treatments for the treatment of vitiligo.

Preventive Effect of Metformin in Radiation-Induced Xerostomia

Radiation induced structural damage of salivary gland including reducing acinar cell and fibrosis. These changes result in hypofunction of salivary gland which has a significant impact on the quality of life of head and neck cancer patients who treated with radiotherapy. Nevertheless, no preventive method has been found. Metformin, a diabetes drug, has recently attracted considerable attention because it can cause tissue regeneration by anti-inflammatory action and influencing stem cells. This study examined the effects of metformin on salivary gland tissue damage caused by radiation therapy. Cultured human parotid epithelial cells are irradiated with 15 Gy of 4MV X-rays. The analysis including DNA damage, inflammatory markers and proliferation, is conducted to confirm the effect of metformin. Similarly, an in vivo mouse model is established. Histologic and functional analyses, such as salivary flow rate and lag time, are performed. The in vitro experiment revealed irradiation increased DNA damage, NF-кB, IL-6, and apoptosis with reduced proliferation. The treatment with metformin decreased the radiation-induced DNA damage and inflammation, and increased proliferation. The in vivo model also shows the same results. The group taking metformin after irradiation has preserved salivary gland parenchyma compared to irradiation only group, and the functional analysis results are comparable to the normal group. Histologic and functional analysis shows that metformin reduced radiation-induced hypofunction of salivary gland. Hence, metformin can be used to prevent radiation-induced salivary gland dysfunction.

Repurposing mitochondria-targeted therapeutics for kidney diseases

The kidney is one of the most metabolically demanding organs in the human body and requires a large amount of energy, in the form of adenosine triphosphate (ATP), to perform and maintain normal kidney functions. To meet this energy demand, proximal tubule cells within the nephron segments of the renal cortex are mitochondrially dense with high oxygen consumption rates. Mitochondria are complex organelles involved in diverse cellular and molecular functions, including the production of ATP, calcium homeostasis, and phospholipid regulation. Mitochondrial dysfunction is critical in the onset and progression of kidney disease. Dysfunctional renal mitochondria have been linked with alterations in redox homeostasis, impaired bioenergetics, oxidative stress, and inflammation, all of which result in renal cell injury and death, as well as fibrotic accumulation in kidney injury and disease. As such, interest in the development and/or repurposing of mitochondria-targeted therapeutics for the potential treatment of kidney diseases has recently surged. Although novel therapeutics and promising new drug targets have been identified, drug repurposing for kidney diseases offers numerous advantages over traditional drug discovery initiatives, including reduced cost, time of therapeutic development, and preclinical testing, in addition to known pharmacokinetics/pharmacodynamics and safety profiles. Here, we provide an overview of mitochondrial dysfunction in the context of kidney injury and disease and shed light on promising mitochondria-targeted therapeutic agents that display repurposing potential for the restoration of kidney function and/or acceleration of renal recovery.

Inulin and hyaluronic acid-based oral liposome for enhanced photo-chemotherapy against orthotopic colon cancer and its reversal effects on tumor hypoxia and intestinal microbiota

Colon cancer has a complex microenvironment and course, and conventional chemotherapy is hindered by low permeability and immunosuppression at the cancer site, leading to poor efficacy. Integrating intestinal environment regulation and molecularly targeted drugs are more attractive strategies. This study aimed to developed an oral colonic targeted delivery system (5-Flu/MET@MSNs/Ce6@HIL) using hyaluronic acid (HA) and inulin (IN) as key components. IN is a polymer with colon-specific targeting capabilities, while HA targets CD44 on the surface of colon cancer cells. We used IN and HA-modified liposomes to co-encapsulate three therapeutic agents, chemotherapy drug 5-Fluorouracil (5-Flu), photosensitizer chlorin e6 (Ce6), and hypoxia reliever metformin (MET). 5-Flu and Ce6 effectively induced cell apoptosis, whereas MET downregulated Hypoxia-Inducible Factor 1-α (HIF-1α) and alleviate the hypoxic microenvironment. In orthotopic colon-tumor-bearing-mice, the final product of 5-Flu@MET@MSNs/Ce6@HIL effectively hindered growth of tumors, which was inhibited by 3.31, 14.31, and 7.88 times when compared to 5-Flu, MET, or Ce6 single-loaded formulations, respectively. Furthermore, after oral administration, the multifunctional liposomes showed good in vivo safety and compliance. In conclusion, this study proposes a novel orthotopic colon-targeted cancer treatment strategy with accurate tumor targeting capabilities, which has certain potential and development value in future clinical applications.

Pinitol Improves Lipopolysaccharide-Induced Cellular Damage in Human Dermal Microvascular Endothelial Cells

3-O-Methyl-D-chiro-inositol (pinitol) has been reported to possess insulin-like effects and is known as one of the anti-diabetic agents for improving muscle and liver function. However, the beneficial effects of pinitol on human dermal microvascular endothelial cells (HDMECs) are not well understood. In this study, we investigated whether pinitol could protect HDMECs from damage induced by lipopolysaccharides (LPSs), which cause various cell defects. We observed that pinitol enhanced wound healing for LPS-damaged HDMECs. We found that pinitol significantly downregulated the LPS-induced upregulation of reactive oxygen species (ROS). Pinitol also significantly restored the mitochondrial membrane potential in these cells. Immunofluorescence analysis revealed that pinitol notably reduced the nuclear localization of NF-κB in LPS-damaged HDMECs. Furthermore, we demonstrated that pinitol decreased the phosphorylation levels of the MAPK family in LPS-damaged HDMECs. Interestingly, we observed that pinitol improved tube formation in LPS-damaged HDMECs. Taken together, we suggest that pinitol exerts several beneficial effects on LPS-damaged HDMECs and may be a promising therapeutic agent for improving vascular-related skin diseases.

High-content screening identifies ganoderic acid A as a senotherapeutic to prevent cellular senescence and extend healthspan in preclinical models

Accumulated senescent cells during the aging process are a key driver of functional decline and age-related disorders. Here, we identify ganoderic acid A (GAA) as a potent anti-senescent compound with low toxicity and favorable drug properties through high-content screening. GAA, a major natural component of Ganoderma lucidum, possesses broad-spectrum geroprotective activity across various species. In C. elegans, GAA treatment extends lifespan and healthspan as effectively as rapamycin. Administration of GAA also mitigates the accumulation of senescent cells and physiological decline in multiple organs of irradiation-stimulated premature aging mice, natural aged mice, and western diet-induced obese mice. Notably, GAA displays a capability to enhance physical function and adapts to conditional changes in metabolic demand as mice aged. Mechanistically, GAA directly binds to TCOF1 to maintain ribosome homeostasis and thereby alleviate cellular senescence. These findings suggest a feasible senotherapeutic strategy for protecting against cellular senescence and age-related pathologies.

Oxidative Phosphorylation Is a Metabolic Vulnerability of Endocrine Therapy-Tolerant Persister Cells in ER+ Breast Cancer

Despite adjuvant treatment with endocrine therapies, estrogen receptor-positive (ER+) breast cancers recur in a significant proportion of patients. Recurrences are attributable to clinically undetectable endocrine-tolerant persister cancer cells that retain tumor-forming potential. Therefore, strategies targeting such persister cells may prevent recurrent disease. Using CRISPR-Cas9 genome-wide knockout screening in ER+ breast cancer cells, we identified a survival mechanism involving metabolic reprogramming with reliance upon mitochondrial respiration in endocrine-tolerant persister cells. Quantitative proteomic profiling showed reduced levels of glycolytic proteins in persisters. Metabolic tracing of glucose revealed an energy-depleted state in persisters, in which oxidative phosphorylation was required to generate ATP. A phase II clinical trial was conducted to evaluate changes in mitochondrial markers in primary ER+/HER2- breast tumors induced by neoadjuvant endocrine therapy (NCT04568616). In an analysis of tumor specimens from 32 patients, tumors exhibiting residual cell proliferation after aromatase inhibitor-induced estrogen deprivation with letrozole showed increased mitochondrial content. Genetic profiling and barcode lineage tracing showed that endocrine-tolerant persistence occurred stochastically without genetic predisposition. Pharmacologic inhibition of mitochondrial complex I suppressed the tumor-forming potential of persisters in mice and synergized with the antiestrogen drug fulvestrant to induce regression of patient-derived xenografts. These findings indicate that mitochondrial metabolism is essential in endocrine-tolerant persister ER+ breast cancer cells and warrant the development of treatment strategies to leverage this vulnerability for treating breast cancer. Significance: Persister cancer cells that survive endocrine therapy exhibit increased energetic dependence upon mitochondria for survival and tumor regrowth potential, indicating that therapies targeting this metabolic dependency could help prevent disease recurrence.

Metformin-Loaded Tannic Acid Nanoparticles Attenuate Osteoarthritis by Promoting Chondrocyte Mitochondria Homeostasis Based on Mitocytosis

The oxidative stress microenvironment and mitochondrial dysfunction in chondrocytes are key mechanisms in the development of osteoarthritis (OA). Metformin (Met) has demonstrated multiple effects on mitochondria and is regarded as a potential therapeutic agent for OA. The low blood flow characteristics in the joint cavity make targeted local delivery of metformin crucial for its clinical application. In this study, tannic acid (TA), with its natural antioxidant and anti-inflammatory properties, was used to prepare self-assemble Met-loaded TA nanoparticles (NPs). The NPs exhibit excellent reactive oxygen scavenging capability, stability in various media, and an acid-responsive release of Met. In Vitro experiments showed that NPs possess excellent biocompatibility, effectively protecting chondrocyte viability in OA's pathological environment and preventing the senescence phenotype. In addition, NPs promoted the expression of antioxidant elements in chondrocytes, restored mitochondrial membrane potential, and enhanced mitocytosis to improve mitochondrial quality. In vivo experiments further confirmed that intra-articular injection of NPs in rats with post-traumatic OA improves cartilage matrix degradation, osteophyte formation, and subchondral bone sclerosis over 8 weeks. Tissue staining further confirmed the protective effects of NPs on chondrocyte mitochondria. Importantly, both in vivo and in vitro experiments revealed that NPs provided superior cellular protection compared to TA or Met alone. Overall, this study demonstrates that NPs effectively against OA cartilage degeneration, with the advantages of easy preparation, high efficiency, and biosafety.

Vinegar-processed Schisandra chinensis polysaccharide ameliorates type 2 diabetes via modulation serum metabolic profiles, gut microbiota, and fecal SCFAs

Numerous studies indicate that Schisandra chinensis (Turcz.) Baill (SC) has anti-type 2 diabetes mellitus (T2DM) effects, and its processed products are commonly used in clinical practice. However, limited reports exist on the mechanisms of polysaccharides from its vinegar products and their role in T2DM. We purified a novel polysaccharide from vinegar-processed Schisandra chinensis (VSC) and used intestinal microbiota 16S rRNA analysis and metabolomics to study changes in T2DM mice after vinegar-processed Schisandra chinensis polysaccharide (VSP) intervention, aiming to elucidate how VSP alleviates T2DM. VSP has shown significant therapeutic effects in T2DM mice, which can regulate the imbalance of glucose and lipid metabolism, alleviate pancreatic and liver damage, restore the integrity of the intestinal barrier, and inhibit the inflammatory response. Serum metabolomics and microbiological analysis showed that VSP could significantly regulate 104 endogenous metabolites and rectify gut microbiota disorders in T2DM mice. Additionally, VSP enhanced the levels of short-chain fatty acids (SCFAs) and the expression of GPR41/43 in the colon of T2DM mice. Correlation analysis revealed significant correlations among specific gut microbiota, serum metabolites, and fecal SCFAs. Overall, these findings will provide a basis for further VSP development.

Metformin's Effects on Cognitive Function from a Biovariance Perspective: A Narrative Review

This study examines the effects of metformin on brain functions focusing on the variability of the results reported in the literature. While some studies suggest that metformin may have neuroprotective effects in diabetic patients, others report an insignificant impact of metformin on cognitive function, or even a negative effect. We propose that this inconsistency may be due to intrinsic cellular-level variability among individuals, which we term "biovariance". Biovariance persists even in demographically homogeneous samples due to complex and stochastic biological processes. Additionally, the complex metabolic actions of metformin, including its influence on neuroenergetics and neuronal survival, may produce different effects depending on individual metabolic characteristics.

Drug Repurposing and Nanotechnology for Topical Skin Cancer Treatment: Redirecting toward Targeted and Synergistic Antitumor Effects

Skin cancer represents a major health concern due to its rising incidence and limited treatment options. Current treatments (surgery, chemotherapy, radiotherapy, immunotherapy, and targeted therapy) often entail high costs, patient inconvenience, significant adverse effects, and limited therapeutic efficacy. The search for novel treatment options is also marked by the high capital investment and extensive development involved in the drug discovery process. In response to these challenges, repurposing existing drugs for topical application and optimizing their delivery through nanotechnology could be the answer. This innovative strategy aims to combine the advantages of the known pharmacological background of commonly used drugs to expedite therapeutic development, with nanosystem-based formulations, which among other advantages allow for improved skin permeation and retention and overall higher therapeutic efficacy and safety. The present review provides a critical analysis of repurposed drugs such as doxycycline, itraconazole, niclosamide, simvastatin, leflunomide, metformin, and celecoxib, formulated into different nanosystems, namely, nanoemulsions and nanoemulgels, nanodispersions, solid lipid nanoparticles, nanostructured lipid carriers, polymeric nanoparticles, hybrid lipid-polymer nanoparticles, hybrid electrospun nanofibrous scaffolds, liposomes and liposomal gels, ethosomes and ethosomal gels, and aspasomes, for improved outcomes in the battle against skin cancer. Enhanced antitumor effects on melanoma and nonmelanoma research models are highlighted, with some nanoparticles even showing intrinsic anticancer properties, leading to synergistic effects. The explored research findings highly evidence the potential of these approaches to complement the currently available therapeutic strategies in the hope that these treatments might one day reach the pharmaceutical market.

The Anti-Aging Mechanism of Metformin: From Molecular Insights to Clinical Applications

Aging represents a complex biological phenomenon marked by the progressive deterioration of physiological functions over time, reduced resilience, and increased vulnerability to age-related diseases, ultimately culminating in mortality. Recent research has uncovered diverse molecular mechanisms through which metformin extends its benefits beyond glycemic control, presenting it as a promising intervention against aging. This review delves into the anti-aging properties of metformin, highlighting its role in mitochondrial energy modulation, activation of the AMPK-mTOR signaling pathway, stimulation of autophagy, and mitigation of inflammation linked to cellular aging. Furthermore, we discuss its influence on epigenetic modifications that underpin genomic stability and cellular homeostasis. Metformin's potential in addressing age-associated disorders including metabolic, cardiovascular, and neurodegenerative diseases is also explored. The Targeting Aging with Metformin (TAME) trial aims to provide key evidence on its efficacy in delaying aging in humans. Despite these promising insights, significant challenges persist in gaining a more comprehensive understanding into its underlying mechanisms, determining optimal dosing strategies, and evaluating long-term safety in non-diabetic populations. Addressing these challenges is crucial to fully realizing metformin's potential as an anti-aging therapeutic.

PGC-1α activation to enhance macrophage immune function in mycobacterial infections

Nontuberculous Mycobacteria (NTM) are a heterogeneous group of environmental microorganisms with distinct human pathogenesis. Their incidence and prevalence are rising worldwide, due in part to elevated antimicrobial resistance which complicates treatment and potential successful outcomes. Although information exists on the clinical significance of NTMs, little is known about host immune response to infection. NTM infections alter macrophage mitochondrial capacity and decrease ATP production, efficient immune response, and bacterial clearance. Transcription factor peroxisome proliferator activated receptor (PPAR) γ coactivator-1α (PGC-1α) is a master regulator of mitochondrial biogenesis, influencing metabolism, mitochondrial pathways, and antioxidant response. Mitochondrial transcription factor A (TFAM) is a protein essential for mitochondrial DNA (mtDNA) genome stability, integrity, and metabolism. Both PGC-1α and TFAM regulate mitochondrial biogenesis and activity, and their disruption is linked to inflammatory signaling and altered macrophage function. We show that NTM causes macrophage mitochondrial damage and disrupted bioenergetics. Mechanistically we show that this is related to attenuation of expression of PGC-1α and TFAM in infected macrophages. Importantly, rescuing expression of PGC-1α and TFAM using pharmacologic approaches restored macrophage immune function. Our results suggest that pharmacologic approaches to enhance mitochondrial function provide a novel approach to target macrophage immune function and means to combat NTM infections.

Metabolic rewiring in skin epidermis drives tolerance to oncogenic mutations

Skin epithelial stem cells correct aberrancies induced by oncogenic mutations. Oncogenes invoke different strategies of epithelial tolerance; while wild-type cells outcompete β-catenin-gain-of-function (βcatGOF) cells, HrasG12V cells outcompete wild-type cells. Here we ask how metabolic states change as wild-type stem cells interface with mutant cells and drive different cell-competition outcomes. By tracking the endogenous redox ratio (NAD(P)H/FAD) with single-cell resolution in the same mouse over time, we discover that βcatGOF and HrasG12V mutations, when interfaced with wild-type epidermal stem cells, lead to a rapid drop in redox ratios, indicating more oxidized cellular redox. However, the resultant redox differential persists through time in βcatGOF, whereas it is flattened rapidly in the HrasG12Vmodel. Using 13C liquid chromatography-tandem mass spectrometry, we find that the βcatGOF and HrasG12V mutant epidermis increase the fractional contribution of glucose through the oxidative tricarboxylic acid cycle. Treatment with metformin, a modifier of cytosolic redox, inhibits downstream mutant phenotypes and reverses cell-competition outcomes of both mutant models.

Dysfunctional BCAA degradation triggers neuronal damage through disrupted AMPK-mitochondrial axis due to enhanced PP2Ac interaction

Metabolic and neurological disorders commonly display dysfunctional branched-chain amino acid (BCAA) metabolism, though it is poorly understood how this leads to neurological damage. We investigated this by generating Drosophila mutants lacking BCAA-catabolic activity, resulting in elevated BCAA levels and neurological dysfunction, mimicking disease-relevant symptoms. Our findings reveal a reduction in neuronal AMP-activated protein kinase (AMPK) activity, which disrupts autophagy in mutant brain tissues, linking BCAA imbalance to brain dysfunction. Mechanistically, we show that excess BCAA-induced mitochondrial reactive oxygen species (ROS) triggered the binding of protein phosphatase 2 A catalytic subunit (PP2Ac) to AMPK, suppressing AMPK activity. This initiated a dysregulated feedback loop of AMPK-mitochondrial interactions, exacerbating mitochondrial dysfunction and oxidative neuronal damage. Our study identifies BCAA imbalance as a critical driver of neuronal damage through AMPK suppression and autophagy dysfunction, offering insights into metabolic-neuronal interactions in neurological diseases and potential therapeutic targets for BCAA-related neurological conditions.

Metformin for Treating Gestational Diabetes: What Have We Learned During the Last Two Decades? A Systematic Review

There has been accumulating evidence over the past two decades that metformin can be an effective treatment for gestational diabetes mellitus (GDM) in women whose diet and exercise fail to attain optimal glycemic control. The objective of this review was to comprehensively analyze all studies investigating the effectiveness of metformin compared to insulin and other drugs utilized for the treatment of GDM. After a comprehensive literature review based on PRISMA 2020, 35 studies were included after a selection process utilizing predetermined inclusion and exclusion criteria. A variety of short-term maternal and neonatal outcomes were assessed. Metformin is a highly efficient medication for attaining optimal control of blood sugar levels in women with GDM, resulting in a significant reduction in the amount of weight gained during pregnancy. Regarding additional maternal outcomes, such as pregnancy-induced hypertension and cesarean deliveries, some studies demonstrate a link between metformin and a reduced occurrence of both conditions. In contrast, others do not find an association. Regarding short-term neonatal outcomes, metformin does not exhibit any changes in gestational age at delivery. In contrast, metformin demonstrated substantial decreases in the likelihood of greater gestational birth weight and neonatal hospitalization when compared to other drugs. When compared primarily to insulin, metformin decreases the probability of several short-term outcomes related to pregnancy and newborns. Additional data are necessary for extended follow-up studies, including patients with GDM treated with metformin.

piR-26441 inhibits mitochondrial oxidative phosphorylation and tumorigenesis in ovarian cancer through m6A modification by interacting with YTHDC1

Ovarian cancer (OC) is a heterogeneous cancer. In contrast to other tumor cells, which rely primarily on aerobic glycolysis (Warburg effect) as their energy source, oxidative phosphorylation (OXPHOS) is also one of its major metabolic modes. Piwi-interacting RNAs (piRNAs) play a regulatory function in various biological processes in tumor cells. However, the role and mechanisms of piRNAs in OC and mitochondrial OXPHOS remain to be elucidated. Here, we found that piR-26441 was aberrantly downregulated in OC, and its overexpression suppressed the malignant features of OC cells and tumor growth in a xenograft model. Moreover, overexpression of piR-26441 significantly reduced mitochondrial OXPHOS levels in OC cells. Furthermore, piR-26441 directly binds to and upregulates the expression of YTHDC1 in OC cells. piR-26441 also increased m6A levels, thereby interacting with YTHDC1 to destabilize the mRNA of TSFM. The resultant TSFM loss reduced mitochondrial complex I activity and mitochondrial OXPHOS, leading to mitochondrial dysfunction in OC cells, increased reactive oxygen species levels, and thus, DNA damage and apoptosis in OC cells, thereby inhibiting OC progression. Additionally, ago-piR-26441 suppressed tumor growth and mitochondrial metabolism in the patient-derived organoid model. Altogether, piR-26441 could inhibit OC cell growth via the YTHDC1/TSFM signaling axis, underscoring its significant importance in the context of OC, as well as offering potential as a therapeutic target.

Targeting mitochondrial function as a potential therapeutic approach for allergic asthma

Allergic asthma is a chronic complex airway disease characterized by airway hyperresponsiveness, eosinophilic inflammation, excessive mucus secretion, and airway remodeling, with increasing mortality and incidence globally. The pathogenesis of allergic asthma is influenced by various factors including genetics, environment, and immune responses, making it complex and diverse. Recent studies have found that various cellular functions of mitochondria such as calcium regulation, adenosine triphosphate production, changes in redox potential, and free radical scavenging, are involved in regulating the pathogenesis of asthma. This review explores the involvement of mitochondrial functional changes in the pathogenesis of asthma, and investigate the potential of targeting cellular mitochondria as a therapeutic approach for asthma. Those insights can provide a novel theoretical foundations and treatment strategies for understanding and preventing asthma.

Movement disorders related to antidiabetic medications: a real-world pharmacovigilance study

BACKGROUND

Diabetic Mellitus (DM) has progressively emerged as a worldwide health problem, leading to the widespread deployment of antidiabetic drugs as the primary therapy in the global population. The incidence of diabetes medications-related movement disorders (drMD) is noteworthy but underestimated by clinical practitioners.

RESEARCH DESIGN AND METHODS

In order to address the incidence of drMD in DM patients and realize the serious outcomes associated with drMD, we conducted a real-world pharmacovigilance study of 612,043 DM patients using the FDA Adverse Event Reporting System (FAERS) database from January 2004 to September 2023. Reporting Odd Ratio (ROR) was calculated to reflect the risk of drMD. A multivariable logistic regression analysis was employed to adjust crude ROR with the mixed factors including age, sex and various antidiabetic treatments. Afterward, a Mendelian Randomization (MR) study was performed to elucidate the underlying genetic correlation between the genetically proxied targets of antidiabetic drugs and motor disorders.

RESULTS

Among 11,729 cases of motor adverse events in DM patients, six categories of drMD were significantly associated with DM medications. Noticeably, metformin was revealed to drastically increase the incidence of parkinsonism (adjusted ROR:3.97; 95 %CI (3.03, 5.19), p = 5.68e-24), bradykinesia (adjusted ROR:1.69; 95 %CI (1.07,2.59), p = 0.02) and irregular hyperkinesia, including chorea, choreoathetosis and athetosis. Insulin/insulin analogues and GLP-1 analogues presented notably higher odds of tremor: the adjusted ROR (aROR) of insulin and GLP-1 analogue is respectively 1.24 (95 %CI (1.15,1.34), p = 2.51e-08) and 1.78 (95 %CI (1.65,1.91), p = 5.64e-54). The combined therapeutic effects of multiple genetic variants of metformin, especially AMP-activated protein kinase (AMPK) were markedly linked to a greater likelihood of developing secondary parkinsonism (OR:10.816, p = 0.049) according to MR analyses.

CONCLUSION

The use of antidiabetic medications was significantly related to an increased incidence of movement disorders in DM patients. Moreover, MR analyses provided further genetic evidence for the pharmacovigilance study. This comprehensive investigation might help physicians recognize neurological adverse events associated with antidiabetic treatments and administer effective interventions.

Exploring the clinical connections between epilepsy and diabetes mellitus: Promising therapeutic strategies utilizing agmatine and metformin

PURPOSE

Diabetes mellitus (DM) and epilepsy and the psychological and socio-economic implications that are associated with their treatments can be quite perplexing. Metformin is an antihyperglycemic medication that is used to treat type 2 DM. In addition, metformin elicits protective actions against multiple diseases, including neurodegeneration and epilepsy. Recent studies indicate that metformin alters the resident gut microbiota in favor of species producing agmatine, an arginine metabolite which, in addition to beneficially altering metabolic pathways, is a potent neuroprotectant and neuromodulant.

METHODS

We first examine the literature for epidemiological and clinical evidences linking DM and epilepsy. Next, basing our analyses on published literature, we propose the possible complementarity of agmatine and metformin in the treatment of DM and epilepsy.

RESULTS

Our analyses of the clinical data suggest a significant association between pathogeneses of epilepsy and DM. Further, both agmatine and metformin appear to be multimodal therapeutic agents and have robust antiepileptogenic and antidiabetic properties. Data from animal and clinical studies largely support the use of metformin/agmatine as a double-edged pharmacotherapeutic agent against DM and epilepsy, particularly in their concurrent pathological occurrences.

CONCLUSION

The present review explores the evidences and available data on possible uses of metformin/agmatine as pertinent antidiabetic and antiepileptic agents. Our hope is that this will stimulate further research on the therapeutic actions of these multimodal agents, particularly for subject-specific clinical outcomes.

Effects of Biguanide-PROTACs in Pancreatic Cancer Cells

This study focuses on the synthesis of Biguanide-PROTACs, formed by conjugating the biguanide motif with a spacer and a ligand for recognition subunits of two E3 ubiquitin ligases. Evaluation of their activity on pancreatic cancer cell (KP4) proliferation established a correlation between membrane permeability and median effective concentration. Mechanistic insights revealed that only two compounds exhibited biguanide-like AMPK activation, while only one hydrophobic compound uniquely altered mitochondrial protein levels. The prospect of developing and expanding the Biguanide-PROTAC library holds several promises, offering potential insights into biguanide mechanisms and the creation of more potent anticancer agents. This study contributes to understanding the intricate interplay between compound structure, permeability, and anticancer activity, paving the way for targeted drug development in pancreatic cancer treatment.

Functional co-delivery nanoliposomes based on improving hypoxia for increasing photoimmunotherapy efficacy of cold tumors

Cold tumors lack T cells infiltration and have low immunogenicity, resulting insufficient immunotherapy response. Therefore, how to realize the transformation from cold tumor to hot tumor is an urgent problem to be solved. Photodynamic therapy can induce immunogenic death of tumor cells (ICD) and activate T lymphocytes to produce tumor immune response. However, hypoxia in the cold tumor microenvironment limits the effectiveness of photodynamic therapy. So in this article, MET-HMME/CAT-HMME@Nlip as a functional co-delivery nanoliposomes was constructed based on overcoming the above problems. Firstly, the oxygen-deficient state could be improved by the following two ways, one is catalase loaded in CAT-HMME@Nlip can decompose high concentration hydrogen peroxide to produce oxygen, and the other is metformin loaded in MET-HMME@Nlip can decrease oxygen consumption by inhibiting of mitochondrial respiration. And then with the increase of substrate oxygen concentration, the sensitivity of photodynamic therapy can be greatly improved and the anti-tumor immune response by PDT-induced ICD can also be enhanced obviously. In addition, metformin could act as a small molecule immune checkpoint inhibitor to reduce the expression of PD-L1 on the surface of tumor cells, thereby effectively improving the specific killing ability of cytotoxic T cells to tumor cells which could not only erasing the primary tumor, but also inhibiting the growth of simulated distant tumors through the immune memory function. This study provides a new idea for improving the clinical treatment effect of hypoxic cold tumors, especially for tumors that could not benefit from immunotherapy due to low or no expression of PD-L1 protein on the surface of tumor cells.

Metformin impacts the differentiation of mouse bone marrow cells into macrophages affecting tumour immunity

Background

Epidemiological studies suggest that metformin reduces the risk of developing several types of cancer, including gliomas, and improves the overall survival in cancer patients. Nevertheless, while the effect of metformin on cancer cells has been extensively studied, its impact on other components of the tumour microenvironment, such as macrophages, is less understood.

Results

Metformin-treated mouse bone marrow cells differentiate into spindle-shaped macrophages exhibiting increased phagocytic activity and tumour cell cytotoxicity coupled with modulated expression of co-stimulatory molecules displaying reduced sensitivity to inflammatory cues compared with untreated cells. Transcriptional analyses of metformin-treated mouse bone marrow-derived macrophages show decreased expression levels of pro-tumour genes, including Tgfbi and Il1β, related to enhanced mTOR/HIF1α signalling and metabolic rewiring towards glycolysis.

Significance

Our study provides novel insights into the immunomodulatory properties of metformin in macrophages and its potential application in preventing tumour onset and in cancer immunotherapy.

Metformin augments major cytoplasmic organization except for spindle organization in oocytes cultured under hyperglycemic and hyperlipidemic conditions: An in vitro study

The present study aimed to investigate the role of antidiabetic drug metformin on the cytoplasmic organization of oocytes. Germinal vesicle (GV) stage oocytes were collected from adult female Swiss albino mice and subjected to in vitro maturation (IVM) in various experimental groups- control, vehicle control (0.3% ethanol), metformin (50 μg/mL), high glucose and high lipid (HGHL, 10 mM glucose; 150 μM palmitic acid; 75 μM stearic acid and 200 μM oleic acid in ethanol), and HGHL supplemented with metformin. The metaphase II (MII) oocytes were analyzed for lipid accumulation, mitochondrial and endoplasmic reticulum (ER) distribution pattern, oxidative and ER stress, actin filament organization, cortical granule distribution pattern, spindle organization and chromosome alignment. An early polar body extrusion was observed in the HGHL group. However, the maturation rate at 24 h did not differ significantly among the experimental groups compared to the control. The HGHL conditions exhibited significantly higher levels of oxidative stress, ER stress, poor actin filament organization, increased lipid accumulation, altered mitochondrial distribution, spindle abnormalities, and chromosome misalignment compared to the control. Except for spindle organization, supplementation of metformin to the HGHL conditions improved all the parameters (non-significant for ER and actin distribution pattern). These results show that metformin exposure in the culture media helped to improve the hyperglycemia and hyperlipidemia-induced cytoplasmic anomalies except for spindle organization. Given the crucial role of spindle organization in proper chromosome segregation during oocyte maturation and meiotic resumption, the implications of metformin's limitations in this aspect warrant careful evaluation and further investigation.

Metformin and its potential influence on cell fate decision between apoptosis and senescence in cancer, with a special emphasis on glioblastoma

Despite reaching enormous achievements in therapeutic approaches worldwide, GBM still remains the most incurable malignancy among various cancers. It emphasizes the necessity of adjuvant therapies from the perspectives of both patients and healthcare providers. Therefore, most emerging studies have focused on various complementary and adjuvant therapies. Among them, metabolic therapy has received special attention, and metformin has been considered as a treatment in various types of cancer, including GBM. It is clearly evident that reaching efficient approaches without a comprehensive evaluation of the key mechanisms is not possible. Among the studied mechanisms, one of the more challenging ones is the effect of metformin on apoptosis and senescence. Moreover, metformin is well known as an insulin sensitizer. However, if insulin signaling is facilitated in the tumor microenvironment, it may result in tumor growth. Therefore, to partially resolve some paradoxical issues, we conducted a narrative review of related studies to address the following questions as comprehensively as possible: 1) Does the improvement of cellular insulin function resulting from metformin have detrimental or beneficial effects on GBM cells? 2) If these effects are detrimental to GBM cells, which is more important: apoptosis or senescence? 3) What determines the cellular decision between apoptosis and senescence?

GPRC6A is a Potential Therapeutic Target for Metformin Regulation of Glucose Homeostasis in Mice

Understanding the mechanism of metformin actions in treating type 2 diabetes is limited by an incomplete knowledge of the specific protein targets mediating its metabolic effects. Metformin has structural similarities to L-Arginine (2-amino-5-guanidinopentanoic acid), which is a ligand for GPRC6A, a Family C G-protein coupled receptor that regulates energy metabolism. Ligand activation of GPRC6A results in lowering of blood glucose and other metabolic changes resembling the therapeutic effect of metformin. In the current study, we tested if metformin activates GPRC6A. We used Alphafold2 to develop a structural model for L-Arginine (L-Arg) binding to the extracellu-lar bilobed venus flytrap domain (VFT) of GPRC6A. We found that metformin docked to the site in the VFT that overlaps the binding site for L-Arg. Metformin resulted in a dose-dependent stimulation of GPRC6A activity in HEK-293 cells transfected with full-length wild-type GPRC6A but not in untransfected control cells. In addition, metformin failed to activate an alternatively spliced GPRC6A isoform lacking the putative binding site in the VFT. More specifically, mutation of the predicted metformin key binding residues Glu170 and Asp303 in the GPRC6A VFT resulted in loss of metformin receptor activation in vitro. The in vivo role of GPRC6A in mediating the effects of metformin was tested in Gprc6a-/- mice. Administration of therapeutic doses of metformin lowered blood glucose levels following a glucose tolerance test in wild-type but not Gprc6a-/- mice. Finally, we EN300, created by adding a carboxymethyl group from L-Arg to the biguanide backbone of metformin. EN300 showed dose-dependent stimulation of GPRC6A activity in vitro with greater potency than L-Arginine, but less than metformin. Thus, we suggest that GPRC6A is a potential molecular target for metformin which may be used to understand the therapeutic actions of metformin and develop novel small molecules to treat T2D.

Early Life Interventions: Impact on Aging and Longevity

Across mammals, lifespans vary remarkably, spanning over a hundredfold difference. Comparative studies consistently reveal a strong inverse relationship between developmental pace and lifespan, hinting at the potential for early-life interventions (ELIs) to influence aging and lifespan trajectories. Focusing on postnatal interventions in mice, this review explores how ELIs influence development, lifespan, and the underlying mechanisms. Previous ELI studies have employed a diverse array of approaches, including dietary modifications, manipulations of the somatotropic axis, and various chemical treatments. Notably, these interventions have demonstrated significant impacts on aging and lifespan in mice. The underlying mechanisms likely involve pathways related to mitochondrial function, mTOR and AMPK signaling, cellular senescence, and epigenetic alterations. Interestingly, ELI studies may serve as valuable models for investigating the complex regulatory mechanisms of development and aging, particularly regarding the interplay among somatic growth, sexual maturation, and lifespan. In addition, prior research has highlighted the intricacies of experimental design and data interpretation. Factors such as timing, sex-specific effects, administration methods, and animal husbandry practices must be carefully considered to ensure the reliability and reproducibility of results, as well as rigorous interpretation. Addressing these factors is essential for advancing our understanding of how development, aging, and lifespan are regulated, potentially opening avenues for interventions that promote healthy aging.

Diabetes and Osteoarthritis: Exploring the Interactions and Therapeutic Implications of Insulin, Metformin, and GLP-1-Based Interventions

Diabetes mellitus (DM) and osteoarthritis (OA) are prevalent chronic conditions with shared pathophysiological links, including inflammation and metabolic dysregulation. This study investigates the potential impact of insulin, metformin, and GLP-1-based therapies on OA progression. Methods involved a literature review of clinical trials and mechanistic studies exploring the effects of these medications on OA outcomes. Results indicate that insulin, beyond its role in glycemic control, may modulate inflammatory pathways relevant to OA, potentially influencing joint health. Metformin, recognized for its anti-inflammatory properties via AMPK activation, shows promise in mitigating OA progression by preserving cartilage integrity and reducing inflammatory markers. GLP-1-based therapies, known for enhancing insulin secretion and improving metabolic profiles in DM, also exhibit anti-inflammatory effects that may benefit OA by suppressing cytokine-mediated joint inflammation and supporting cartilage repair mechanisms. Conclusions suggest that these medications, while primarily indicated for diabetes management, hold therapeutic potential in OA by targeting common underlying mechanisms. Further clinical trials are warranted to validate these findings and explore optimal therapeutic strategies for managing both DM and OA comorbidities effectively.

Targeting cancer and immune cell metabolism with the complex I inhibitors metformin and IACS-010759

Metformin and IACS-010759 are two distinct antimetabolic agents. Metformin, an established antidiabetic drug, mildly inhibits mitochondrial complex I, while IACS-010759 is a new potent mitochondrial complex I inhibitor. Mitochondria is pivotal in the energy metabolism of cells by providing adenosine triphosphate through oxidative phosphorylation (OXPHOS). Hence, mitochondrial metabolism and OXPHOS become a vulnerability when targeted in cancer cells. Both drugs have promising antitumoral effects in diverse cancers, supported by preclinical in vitro and in vivo studies. We present evidence of their direct impact on cancer cells and their immunomodulatory effects. In clinical studies, while observational epidemiologic studies on metformin were encouraging, actual trial results were not as expected. However, IACS-01075 exhibited major adverse effects, thereby causing a metabolic shift to glycolysis and elevated lactic acid concentrations. Therefore, the future outlook for these two drugs depends on preventive clinical trials for metformin and investigations into the plausible toxic effects on normal cells for IACS-01075.

Metformin exposure and the incidence of lactic acidosis in critically ill patients with T2DM: A retrospective cohort study

OBJECTIVE

The objective of this study was to investigate the correlation between metformin exposure and the incidence of lactic acidosis in critically ill patients.

METHODS

The patients with type 2 diabetes mellitus (T2DM) were included from Medical Information Mart for Intensive Care IV database (MIMIC-IV). The primary outcome was the incidence of lactic acidosis. The secondary outcomes were lactate level and in-hospital mortality. Propensity score matching (PSM) method was adopted to reduce bias of the confounders. The multivariate logistic regression was used to explore the correlation between metformin exposure and the incidence of lactic acidosis. Subgroup analysis and sensitivity analysis were used to test the stability of the conclusion.

RESULTS

We included 4939 patients. There were 2070 patients in the metformin group, and 2869 patients in the nonmetformin group. The frequency of lactic acidosis was 5.7% (118/2070) in the metformin group and it was 4.3% (122/2869) in the nonmetformin group. There was a statistically significant difference between the two groups (P < 0.05). The lactate level in the metformin group was higher than in the nonmetformin group (2.78 ± 2.23 vs. 2.45 ± 2.24, P < 0.001). After PSM, the frequency of lactic acidosis (6.3% vs. 3.7%, P < 0.001) and lactate level (2.85 ± 2.38 vs. 2.40 ± 2.14, P < 0.001) were significantly higher in the metformin group compared with the nonmetformin group. In multivariate logistic models, the frequency of lactic acidosis was obviously increased in metformin group, and the adjusted odds ratio (OR) of metformin exposure was 1.852 (95% confidence interval (CI) = 1.298-2.643, P < 0.001). The results were consistent with subgroup analysis except for respiratory failure subgroup. Metformin exposure increased lactate level but did not affect the frequency of lactic acidosis in patients of respiratory failure with hypercapnia. However, the in-hospital mortality between metformin and nonmetformin group had no obvious difference (P = 0.215). In sensitivity analysis, metformin exposure showed similar effect as the original cohort.

CONCLUSIONS

In critically ill patients with T2DM, metformin exposure elevated the incidence of lactic acidosis except for patients of respiratory failure with hypercapnia, but did not affect the in-hospital mortality.

Potentials of Natural Antioxidants in Reducing Inflammation and Oxidative Stress in Chronic Kidney Disease

Chronic kidney disease (CKD) presents a substantial global public health challenge, with high morbidity and mortality. CKD patients often experience dyslipidaemia and poor glycaemic control, further exacerbating inflammation and oxidative stress in the kidney. If left untreated, these metabolic symptoms can progress to end-stage renal disease, necessitating long-term dialysis or kidney transplantation. Alleviating inflammation responses has become the standard approach in CKD management. Medications such as statins, metformin, and GLP-1 agonists, initially developed for treating metabolic dysregulation, demonstrate promising renal therapeutic benefits. The rising popularity of herbal remedies and supplements, perceived as natural antioxidants, has spurred investigations into their potential efficacy. Notably, lactoferrin, Boerhaavia diffusa, Amauroderma rugosum, and Ganoderma lucidum are known for their anti-inflammatory and antioxidant properties and may support kidney function preservation. However, the mechanisms underlying the effectiveness of Western medications and herbal remedies in alleviating inflammation and oxidative stress occurring in renal dysfunction are not completely known. This review aims to provide a comprehensive overview of CKD treatment strategies and renal function preservation and critically discusses the existing literature's limitations whilst offering insight into the potential antioxidant effects of these interventions. This could provide a useful guide for future clinical trials and facilitate the development of effective treatment strategies for kidney functions.

Candidate molecular targets uncovered in mouse lifespan extension studies

INTRODUCTION

Multiple interventions have demonstrated an increase in mouse lifespan. However, non-standardized controls, sex or strain-specific factors, and insufficient focus on targets, hinder the translation of these findings into clinical applications.

AREAS COVERED

We examined the effects of genetic and drug-based interventions on mice from databases DrugAge, GenAge, the Mouse Phenome Database, and publications from PubMed that led to a lifespan extension of more than 10%, identifying specific molecular targets that were manipulated to achieve the maximum lifespan in mice. Subsequently, we characterized 10 molecular targets influenced by these interventions, with particular attention given to clinical trials and potential indications for each.

EXPERT OPINION

To increase the translational potential of mice life-extension studies to clinical research several factors are crucial: standardization of mice lifespan research approaches, the development of clear criteria for control and experimental groups, the establishment of criteria for potential geroprotectors, and focusing on targets and their clinical application. Pinpointing the targets affected by geroprotectors helps in understanding species-specific differences and identifying potential side effects, ensuring the safety and effectiveness of clinical trials. Additionally, target review facilitates the optimization of treatment protocols and the evaluation of the clinical feasibility of translating research findings into practical therapies for humans.

Relevance of real-time analyzers to determine mitochondrial quality in endothelial cells and oxidative stress in preeclampsia

Oxidative stress and mitochondrial dysfunction are important elements for the pathophysiology of preeclampsia (PE), a multisystemic hypertensive syndrome of pregnancy, characterized by endothelial dysfunction and responsible for a large part of maternal and fetal morbidity and mortality worldwide. Researchers have dedicated their efforts to unraveling the intricate ways in which certain molecules influence both energy metabolism and oxidative stress. Exploring established methodologies from existing literature, shows that these investigations predominantly focus on the placenta, identified as a pivotal source that drives the changes observed in the disease. In this review, we discuss the role of oxidative stress in pathophysiology of PE, as well as metabolic/endothelial dysfunction. We further discuss the use of seahorse analyzers to study real-time bioenergetics of endothelial cells. Although the benefits are clear, few studies have presented results using this method to assess mitochondrial metabolism in these cells. We performed a search on MEDLINE/PubMed using the terms "Seahorse assay and endothelial dysfunction in HUVEC" as well as "Seahorse assay and preeclampsia". From our research, we selected 16 original peer-review papers for discussion. Notably, the first search retrieved studies involving Human Umbilical Vein Endothelial Cells (HUVECs) but none investigating bioenergetics in PE while the second search retrieved studies exploring the technique in PE but none of the studies used HUVECs. Additional studies are required to investigate real-time mitochondrial bioenergetics in PE. Clearly, there is a need for more complete studies to examine the nuances of mitochondrial bioenergetics, focusing on the contributions of HUVECs in the context of PE.

Polyphenols mediated attenuation of diabetes associated cardiovascular complications: A comprehensive review

Background

Diabetes mellitus is a common chronic metabolic disorder that is characterized by increased levels of glucose for prolonged periods of time. Incessant hyperglycemia leads to diabetic complications such as retinopathy, nephropathy, and neuropathy, and cardiovascular complications such as ischemic heart disease, peripheral vascular disease, diabetic cardiomyopathy, stroke, etc. There are many studies that suggest that various polyphenols affect glucose homeostasis and can help to attenuate the complications associated with diabetes.

Objective

This review focuses on the possible role of various dietary polyphenols in palliating diabetes-induced cardiovascular complications. This review also aims to give an overview of the interrelationship among ROS production (due to diabetes), inflammation, glycoxidative stress, and cardiovascular complications as well as the anti-hyperglycemic effects of dietary polyphenols.

Methods

Various scientific databases including Scopus, Web of Science, Google Scholar, PubMed, Science Direct, Springer Link, and Wiley Online Library were used for searching articles that complied with the inclusion and exclusion criteria.

Results

This review lists several polyphenols based on various pre-clinical and clinical studies that have anti-hyperglycemic potential as well as a protective function against cardiovascular complications.

Conclusion

Several pre-clinical and clinical studies suggest that various dietary polyphenols can be a promising intervention for the attenuation of diabetes-associated cardiovascular complications.

Inhibition of mammalian mtDNA transcription acts paradoxically to reverse diet-induced hepatosteatosis and obesity

The oxidative phosphorylation system1 in mammalian mitochondria plays a key role in transducing energy from ingested nutrients2. Mitochondrial metabolism is dynamic and can be reprogrammed to support both catabolic and anabolic reactions, depending on physiological demands or disease states. Rewiring of mitochondrial metabolism is intricately linked to metabolic diseases and promotes tumour growth3-5. Here, we demonstrate that oral treatment with an inhibitor of mitochondrial transcription (IMT)6 shifts whole-animal metabolism towards fatty acid oxidation, which, in turn, leads to rapid normalization of body weight, reversal of hepatosteatosis and restoration of normal glucose tolerance in male mice on a high-fat diet. Paradoxically, the IMT treatment causes a severe reduction of oxidative phosphorylation capacity concomitant with marked upregulation of fatty acid oxidation in the liver, as determined by proteomics and metabolomics analyses. The IMT treatment leads to a marked reduction of complex I, the main dehydrogenase feeding electrons into the ubiquinone (Q) pool, whereas the levels of electron transfer flavoprotein dehydrogenase and other dehydrogenases connected to the Q pool are increased. This rewiring of metabolism caused by reduced mtDNA expression in the liver provides a principle for drug treatment of obesity and obesity-related pathology.

Nanozyme as a rising star for metabolic disease management

Nanozyme, characterized by outstanding and inherent enzyme-mimicking properties, have emerged as highly promising alternatives to natural enzymes owning to their exceptional attributes such as regulation of oxidative stress, convenient storage, adjustable catalytic activities, remarkable stability, and effortless scalability for large-scale production. Given the potent regulatory function of nanozymes on oxidative stress and coupled with the fact that reactive oxygen species (ROS) play a vital role in the occurrence and exacerbation of metabolic diseases, nanozyme offer a unique perspective for therapy through multifunctional activities, achieving essential results in the treatment of metabolic diseases by directly scavenging excess ROS or regulating pathologically related molecules. The rational design strategies, nanozyme-enabled therapeutic mechanisms at the cellular level, and the therapies of nanozyme for several typical metabolic diseases and underlying mechanisms are discussed, mainly including obesity, diabetes, cardiovascular disease, diabetic wound healing, and others. Finally, the pharmacokinetics, safety analysis, challenges, and outlooks for the application of nanozyme are also presented. This review will provide some instructive perspectives on nanozyme and promote the development of enzyme-mimicking strategies in metabolic disease therapy.

View on Metformin: Antidiabetic and Pleiotropic Effects, Pharmacokinetics, Side Effects, and Sex-Related Differences

Metformin is a synthetic biguanide used as an antidiabetic drug in type 2 diabetes mellitus, achieved by studying the bioactive metabolites of Galega officinalis L. It is also used off-label for various other diseases, such as subclinical diabetes, obesity, polycystic ovary syndrome, etc. In addition, metformin is proposed as an add-on therapy for several conditions, including autoimmune diseases, neurodegenerative diseases, and cancer. Although metformin has been used for many decades, it is still the subject of many pharmacodynamic and pharmacokinetic studies in light of its extensive use. Metformin acts at the mitochondrial level by inhibiting the respiratory chain, thus increasing the AMP/ATP ratio and, subsequently, activating the AMP-activated protein kinase. However, several other mechanisms have been proposed, including binding to presenilin enhancer 2, increasing GLP1 release, and modification of microRNA expression. Regarding its pharmacokinetics, after oral administration, metformin is absorbed, distributed, and eliminated, mainly through the renal route, using transporters for cationic solutes, since it exists as an ionic molecule at physiological pH. In this review, particular consideration has been paid to literature data from the last 10 years, deepening the study of clinical trials inherent to new uses of metformin, the differences in effectiveness and safety observed between the sexes, and the unwanted side effects. For this last objective, metformin safety was also evaluated using both VigiBase and EudraVigilance, respectively, the WHO and European databases of the reported adverse drug reactions, to assess the extent of metformin side effects in real-life use.

Progress in the treatment of diabetic cardiomyopathy, a systematic review

Diabetic cardiomyopathy (DCM) is a condition characterized by myocardial dysfunction that occurs in individuals with diabetes, in the absence of coronary artery disease, valve disease, and other conventional cardiovascular risk factors such as hypertension and dyslipidemia. It is considered a significant and consequential complication of diabetes in the field of cardiovascular medicine. The primary pathological manifestations include myocardial hypertrophy, myocardial fibrosis, and impaired ventricular function, which can lead to widespread myocardial necrosis. Ultimately, this can progress to the development of heart failure, arrhythmias, and cardiogenic shock, with severe cases even resulting in sudden cardiac death. Despite several decades of both fundamental and clinical research conducted globally, there are currently no specific targeted therapies available for DCM in clinical practice, and the incidence and mortality rates of heart failure remain persistently high. Thus, this article provides an overview of the current treatment modalities and novel techniques pertaining to DCM, aiming to offer valuable insights and support to researchers dedicated to investigating this complex condition.

Integrated analyses revealed the potential role and immune link of mitochondrial dysfunction between periodontitis and type 2 diabetes mellitus

There is a reciprocal comorbid relationship between periodontitis and type 2 diabetes mellitus (T2DM). Recent studies have suggested that mitochondrial dysfunction (MD) could be the key driver underlying this comorbidity. The aim of this study is to provide novel understandings into the potential molecular mechanisms between MD and the comorbidity, and identify potential therapeutic targets for personalized clinical management. MD-related differentially expressed genes (MDDEGs) were identified. Enrichment analyses and PPI network analysis were then conducted. Six algorithms were used to explore the hub MDDEGs, and these were validated by ROC analysis and qRT-PCR. Co-expression and potential drug targeting analyses were then performed. Potential biomarkers were identified using LASSO regression. The immunocyte infiltration levels in periodontitis and T2DM were evaluated via CIBERSORTx and validated in mouse models. Subsequently, MD-related immune-related genes (MDIRGs) were screened by WGCNA. The in vitro experiment verified that MD was closely associated with this comorbidity. GO and KEGG analyses demonstrated that the connection between periodontitis and T2DM was mainly enriched in immuno-inflammatory pathways. In total, 116 MDDEGs, eight hub MDDEGs, and two biomarkers were identified. qRT-PCR revealed a distinct hub MDDEG expression pattern in the comorbidity group. Altered immunocytes in disease samples were identified, and their correlations were explored. The in vivo examination revealed higher infiltration levels of inflammatory immunocytes. The findings of this study provide insight into the mechanism underlying the gene-mitochondria-immunocyte network and provide a novel reference for future research into the function of mitochondria in periodontitis and T2DM.

Age-dependent effects of metformin on human oligodendrocyte lineage cell ensheathment capacity

Metformin restores the myelination potential of aged rat A2B5+ oligodendrocyte progenitor cells and may enhance recovery in children with post-radiation brain injury. Human late progenitor cells (O4+A2B5+) have a superior capacity to ensheath nanofibres compared to mature oligodendrocytes, with cells from paediatric sources exceeding adults. In this study, we assessed the effects of metformin on ensheathment capacity of human adult and paediatric progenitors and mature oligodendrocytes and related differences to transcriptional changes. A2B5+ progenitors and mature cells, derived from surgical tissues by immune-magnetic separation, were assessed for ensheathment capacity in nanofibre plates over 2 weeks. Metformin (10 µM every other day) was added to selected cultures. RNA was extracted from treated and control cultures after 2 days. For all ages, ensheathment by progenitors exceeded mature oligodendrocytes. Metformin enhanced ensheathment by adult donor cells but reduced ensheathment by paediatric cells. Metformin marginally increased cell death in paediatric progenitors. Metformin-induced changes in gene expression are distinct for each cell type. Adult progenitors showed up-regulation of pathways involved in the process of outgrowth and promoting lipid biosynthesis. Paediatric progenitors showed a relatively greater proportion of down- versus up-regulated pathways, these involved cell morphology, development and synaptic transmission. Metformin-induced AMP-activated protein kinase activation in all cell types; AMP-activated protein kinase inhibitor BML-275 reduced functional metformin effects only with adult cells. Our results indicate age and differentiation stage-related differences in human oligodendroglia lineage cells in response to metformin. Clinical trials for demyelinating conditions will indicate how these differences translate in vivo.

Targeting Neutrophil Extracellular Traps in Gouty Arthritis: Insights into Pathogenesis and Therapeutic Potential

Gouty arthritis (GA) is an immune-mediated disorder characterized by severe inflammation due to the deposition of monosodium urate (MSU) crystals in the joints. The pathophysiological mechanisms of GA are not yet fully understood, and therefore, the identification of effective therapeutic targets is of paramount importance. Neutrophil extracellular traps (NETs), an intricate structure of DNA scaffold, encompassing myeloperoxidase, histones, and elastases - have gained significant attention as a prospective therapeutic target for gouty arthritis, due to their innate antimicrobial and immunomodulatory properties. Hence, exploring the therapeutic potential of NETs in gouty arthritis remains an enticing avenue for further investigation. During the process of gouty arthritis, the formation of NETs triggers the release of inflammatory cytokines, thereby contributing to the inflammatory response, while MSU crystals and cytokines are sequestered and degraded by the aggregation of NETs. Here, we provide a concise summary of the inflammatory processes underlying the initiation and resolution of gouty arthritis mediated by NETs. Furthermore, this review presents an overview of the current pharmacological approaches for treating gouty arthritis and summarizes the potential of natural and synthetic product-based inhibitors that target NET formation as novel therapeutic options, alongside elucidating the intrinsic challenges of these inhibitors in NETs research. Lastly, the limitations of HL-60 cell as a suitable substitute of neutrophils in NETs research are summarized and discussed. Series of recommendations are provided, strategically oriented towards guiding future investigations to effectively address these concerns. These findings will contribute to an enhanced comprehension of the interplay between NETs and GA, facilitating the proposition of innovative therapeutic strategies and novel approaches for the management of GA.