Review of Biguanide (Metformin) Toxicity

Advances in metformin-delivery systems for diabetes and obesity management

Metformin is a medication that is commonly prescribed to manage type 2 diabetes. It has been used for more than 60 years and is highly effective in lowering blood glucose levels. Recent studies indicate that metformin may have additional medical benefits beyond treating diabetes, revealing its potential therapeutic uses. Oral medication is commonly used to administer metformin because of its convenience and cost-effectiveness. However, there are challenges in optimizing its effectiveness. Gastrointestinal side effects and limitations in bioavailability have led to the underutilization of metformin. Innovative drug-delivery systems such as fast-dissolving tablets, micro/nanoparticle formulations, hydrogel and microneedles have been explored to optimize metformin therapy. These strategies enhance metformin dosage, targeting, bioavailability and stability, and provide personalized treatment options for improved glucose homeostasis, antiobesity and metabolic health benefits. Developing new delivery systems for metformin shows potential for improving therapeutic outcomes, broadening its applications beyond diabetes management and addressing unmet medical needs in various clinical settings. However, it is important to improve drug-delivery systems, addressing issues such as complexity, cost, biocompatibility, stability during storage and transportation, loading capacity, required technologies and biomaterials, targeting precision and regulatory approval. Addressing these limitations is crucial for effective, safe and accessible drug delivery in clinical practice. In this review, recent advances in the development and application of metformin-delivery systems for diabetes and obesity are discussed.

Metformin Therapy for Acne Vulgaris: A Meta-Analysis

Acne vulgaris is a common disease, which occurs in adolescents as well as adults and has a significant influence on the patient's quality of life (QoL) in every aspect. Due to resistance to standard therapies, it has become necessary to prospect for new treatment strategies. It is important to highlight that the diagnosis and treatment of the underlying cause of acne such as metabolic and hormonal disorders may significantly improve the effectiveness of acne treatment. The correlation between Insulin Resistance (IR) and acne has been proven. Both disorders share many common occurrence factors and activation pathways. Metformin, an antihyperglycemic agent, seems to be a possible therapy option, not only because of its insulin sensitizing ability but also via plenty of additional effects of this medicine. While the efficiency of metformin therapy in patients with acne and Polycystic Ovary Syndrome (PCOS) is well explored, it is still necessary to evaluate it in patients without any endocrinopathies. This meta-analysis aimed to estimate the effectiveness of oral metformin as a monotherapy in acne patients without PCOS or other endocrinopathies. Study selection was performed with included criteria such as no PCOS and other endocrinopathies diagnosed, oral administration of metformin, and metformin in monotherapy. Selected studies contained comparisons in the Global Acne Grading System (GAGS) before and after metformin therapy. Statistical analysis detected significant improvement in skin condition after treatment with metformin.

Therapeutic Effect of Desmodium caudatum Extracts on Alleviating Diabetic Nephropathy Mice

Desmodium caudatum extracts (DCE) were investigated for their potential therapeutic effects on diabetic nephropathy (DN). In our study, the high-fat diet (HFD) / streptozotocin (STZ)-induced DN model in C57BL/6 mice was treated with 100 mg/kg, 200 mg/kg DCE. The results showed that DCE decreased biochemical parameters and proteinuria levels. The kidney sections staining indicated that DCE treatment recovered glomerular atrophy and alleviated lipid droplets in the glomerular. Additionally, DCE inhibited lipid and glycogen accumulation down-regulated the expression of sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FAS) proteins. DCE also reduced collagenous fibrous tissue and the expression of transforming growth factor-β1 (TGF-β1) and alpha-smooth muscle actin (α-SMA) through Masson's trichrome staining and immunohistochemical analysis. We found that DCE alleviated hydroxyproline content, and epithelial-mesenchymal transition (EMT). Besides, the results shown that DCE enhanced the antioxidant enzymes to mitigate fibrosis by reducing oxidative stress. In conclusion, our study provided evidence of the protective effect of DCE which down-regulated hyperglycemia, hyperlipidemia and inhibition of TGF-β1 and EMT pathway but elevated antioxidant, suggesting its therapeutic implication for DN.

Kaempferol efficacy in metabolic diseases: Molecular mechanisms of action in diabetes mellitus, obesity, non-alcoholic fatty liver disease, steatohepatitis, and atherosclerosis

The incidence of metabolic diseases has progressively increased, which has a negative impact on human health and life safety globally. Due to the good efficacy and limited side effects, there is growing interest in developing effective drugs to treat metabolic diseases from natural compounds. Kaempferol (KMP), an important flavonoid, exists in many vegetables, fruits, and traditional medicinal plants. Recently, KMP has received widespread attention worldwide due to its good potential in the treatment of metabolic diseases. To promote the basic research and clinical application of KMP, this review provides a timely and comprehensive summary of the pharmacological advances of KMP in the treatment of four metabolic diseases and its potential molecular mechanisms of action, including diabetes mellitus, obesity, non-alcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), and atherosclerosis. According to the research, KMP shows remarkable therapeutic effects on metabolic diseases by regulating multiple signaling transduction pathways such as NF-κB, Nrf2, AMPK, PI3K/AKT, TLR4, and ER stress. In addition, the most recent literature on KMP's natural source, pharmacokinetics studies, as well as toxicity and safety are also discussed in this review, thus providing a foundation and evidence for further studies to develop novel and effective drugs from natural compounds. Collectively, our manuscript strongly suggested that KMP could be a promising candidate for the treatment of metabolic diseases.

A Case of Metformin-Associated Lactic Acidosis Complicated by Acute Liver Failure, Acute Renal Failure, and Shock

Metformin is an oral antihyperglycemic agent used for type 2 diabetes mellitus (T2DM) management and is considered to be the first-line treatment for diabetic patients. It works by improving insulin sensitivity, reducing intestinal absorption, and decreasing glucose production in the liver, leading to decreased blood glucose levels. It is generally considered a safe drug; however, it is associated with an uncommon but serious side effect known as metformin-associated lactic acidosis (MALA), a potentially life-threatening condition. Patients with renal failure and liver disease are at high risk of developing MALA; therefore, the medication should be used cautiously in these patients. The diagnosis of MALA requires high suspicion from the physician of this specific entity; otherwise, it may be easily missed. Herein, we report a case of a 63-year-old female with alcoholic liver disease on metformin who was found to have MALA complicated by acute decompensated liver failure, renal failure, and shock.

Fucoidan alleviates high sucrose-induced metabolic disorders and enhances intestinal homeostasis through modulation of Notch signaling

INTRODUCTION

The therapeutic potential of fucoidan (FUC), a natural polysaccharide, in metabolic disorders is recognized, yet its underlying mechanisms remain unclear.

METHODS

We conducted investigations into the therapeutic mechanisms of FUC sourced from Sargassum fulvellum concerning metabolic disorders induced by a high-sucrose diet (HSD), employing Drosophila melanogaster and mice models. Drosophila larvae were subjected to HSD exposure to monitor growth inhibition, reduced pupation, and developmental delays. Additionally, we examined the impact of FUC on growth- and development-related hormones in Drosophila. Furthermore, we assessed the modulation of larval intestinal homeostasis by FUC, focusing on the regulation of Notch signaling. In mice, we evaluated the effects of FUC on HSD-induced impairments in intestinal epithelial barrier integrity and gut hormone secretion.

RESULTS

FUC supplementation significantly enhanced pupal weight in Drosophila larvae and effectively countered HSD-induced elevation of glucose and triglyceride levels. It notably influenced the expression of growth- and development-related hormones, particularly augmenting insulin-like peptides production while mitigating larval growth retardation. FUC also modulated larval intestinal homeostasis by negatively regulating Notch signaling, thereby protecting against HSD-induced metabolic stress. In mice, FUC ameliorated HSD-induced impairments in ileum epithelial barrier integrity and gut hormone secretion.

CONCLUSIONS

Our findings demonstrate the multifaceted therapeutic effects of FUC in mitigating metabolic disorders and maintaining intestinal health. FUC holds promise as a therapeutic agent, with its effects attributed partly to the sulfate group and its ability to regulate Notch signaling, emphasizing its potential for addressing metabolic disorders.

Metformin: From Diabetes to Cancer-Unveiling Molecular Mechanisms and Therapeutic Strategies

Metformin, a widely used anti-diabetic drug, has garnered attention for its potential in cancer management, particularly in breast and colorectal cancer. It is established that metformin reduces mitochondrial respiration, but its specific molecular targets within mitochondria vary. Proposed mechanisms include inhibiting mitochondrial respiratory chain Complex I and/or Complex IV, and mitochondrial glycerophosphate dehydrogenase, among others. These actions lead to cellular energy deficits, redox state changes, and several molecular changes that reduce hyperglycemia in type 2 diabetic patients. Clinical evidence supports metformin's role in cancer prevention in type 2 diabetes mellitus patients. Moreover, in these patients with breast and colorectal cancer, metformin consumption leads to an improvement in survival outcomes and prognosis. The synergistic effects of metformin with chemotherapy and immunotherapy highlights its potential as an adjunctive therapy for breast and colorectal cancer. However, nuanced findings underscore the need for further research and stratification by molecular subtype, particularly for breast cancer. This comprehensive review integrates metformin-related findings from epidemiological, clinical, and preclinical studies in breast and colorectal cancer. Here, we discuss current research addressed to define metformin's bioavailability and efficacy, exploring novel metformin-based compounds and drug delivery systems, including derivatives targeting mitochondria, combination therapies, and novel nanoformulations, showing enhanced anticancer effects.

Metformin-Associated Lactic Acidosis-Is This on Your Radar?

BACKGROUND

Metformin is a biguanide hyperglycemic agent used to manage non-insulin-dependent diabetes mellitus. Adverse reactions include mainly mild gastrointestinal adverse effects, but severe complications, such as metformin-associated lactic acidosis (MALA) can occur. Metformin is excreted renally and, therefore, not recommended in patients with renal impairment. The reported incidence of MALA is 3 cases per 100,000 patient-years.

CASE REPORT

A 79-year-old woman with a complex medical history, including end-stage renal disease on dialysis and type 2 diabetes, presented to the emergency department (ED) for altered mental status. Prior to arrival, she was found to be hypoglycemic. Her laboratory results were significant for creatinine of 6.56 mg/dL and an anion gap of 52 mmol/L. The venous blood gas revealed a venous pH of 6.857 [reference range (7.32-7.43)], pCO2 of 15.9 mm Hg (40.6-60 mm Hg), HCO3 of 2.7 mmol/L (21-30 mmol/L), lactate of 27 mmol/L (0.5-2 mmol/L), and ammonia of 233 µmol/L. The patient was dialyzed emergently in the ED; repeat laboratory test results showed blood urea nitrogen of 10 mg/dL, creatinine of 1.65 mg/dL, carbon dioxide of 26 mmol/L, and anion gap of 13 mmol/L. The repeat ammonia was 16 µmol/L. The patient's metabolic encephalopathy resolved, and she was discharged home on hospital day 3. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: MALA has a high mortality rate (36%). Laboratory markers have not been found to be a reliable predictor of mortality. Sodium bicarbonate is controversial, but a pH < 7.15 indicates consideration of its use. A pH < 7.1 and a lactate level > 20 mmol/L indicate the need for emergent hemodialysis. Prompt recognition and management in the ED with early hemodialysis can result in good patient outcomes, with a return to their baseline function despite severe laboratory findings.

Bioequivalence and Safety Assessment of 2 Formulations of Low-Dose Metformin Hydrochloride under Fasting Conditions in Healthy Chinese Participants: A Randomized Phase 1 Clinical Trial

The incidence of type 2 diabetes is high, and the existing metformin hydrochloride (MH) tablets of 250 mg cannot meet the demands of the Chinese drug market. This study aimed to evaluate the bioequivalence and safety of generic formulations of MH tablets (test formulation [T], 250 mg/tablet) and innovative products (reference formulation [R], 250 mg/tablet) under fasting conditions. This was an open-label, single-dose, 2-period, 2-sequence crossover, single-center, randomized phase I clinical trial. T and R were considered bioequivalent if the adjusted geometric mean ratios (GMRs) and 90% confidence intervals of the area under the curve (AUC) and maximum concentration (Cmax ) were within the range of 0.8-1.25. Thirty-five participants completed the trial. The T/R adjusted GMRs (95.7% for Cmax , 98.7% for AUC0→t , 98.8% for AUC0→∞ ) were within the acceptable bioequivalence range of 80%-125%. No serious adverse events or suspected or unexpected serious adverse reactions occurred during this trial. The study findings confirmed that generic MH is a well-tolerated and bioequivalent alternative to innovative products under fasting conditions in healthy Chinese participants. (www.chinadrugtrials.org.cn; registration no. CTR20190356).

Impacts of chitosan and its nanoformulations on the metabolic syndromes: a review

A significant public health issue worldwide is metabolic syndrome, a cluster of metabolic illnesses that comprises insulin resistance, obesity, dyslipidemia, hyperglycemia, and hypertension. The creation of natural treatments and preventions for metabolic syndrome is crucial. Chitosan, along with its nanoformulations, is an oligomer of chitin, the second-most prevalent polymer in nature, which is created via deacetylation. Due to its plentiful biological actions in recent years, chitosan and its nanoformulations have drawn much interest. Recently, the chitosan nanoparticle-based delivery of CRISPR-Cas9 has been applied in treating metabolic syndromes. The benefits of chitosan and its nanoformulations on insulin resistance, obesity, diabetes mellitus, dyslipidemia, hyperglycemia, and hypertension will be outlined in the present review, highlighting potential mechanisms for the avoidance and medication of the metabolic syndromes by chitosan and its nanoformulations.

Therapeutic effects of anti-diabetic drugs on traumatic brain injury

AIMS

In this narrative review, we have analyzed and synthesized current studies relating to the effects of anti-diabetic drugs on traumatic brain injury (TBI) complications.

METHODS

Eligible studies were collected from Scopus, Google Scholar, PubMed, and Cochrane Library for clinical, in-vivo, and in-vitro studies published on the impact of anti-diabetic drugs on TBI.

RESULTS

Traumatic brain injury (TBI) is a serious brain disease that is caused by any type of trauma. The pathophysiology of TBI is not yet fully understood, though physical injury and inflammatory events have been implicated in TBI progression. Several signaling pathways are known to play pivotal roles in TBI injuries, including Nuclear factor erythroid 2-related factor 2 (Nrf2), High mobility group box 1 protein/Nuclear factor kappa B (HMGB1/NF-κB), Adiponectin, Mammalian Target of Rapamycin (mTOR), Toll-Like Receptor (TLR), Wnt/β-catenin, Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT), Nod-like receptor protein3 (NLRP3) inflammasome, Phosphoglycerate kinase 1/Kelch-like ECH-associated protein 1 (PGK1/KEAP1)/Nrf2, and Mitogen-activated protein kinase (MAPK) . Recent studies suggest that oral anti-diabetic drugs such as biguanides, thiazolidinediones (TZDs), sulfonylureas (SUs), sodium-glucose cotransporter-2 inhibitors (SGLT2is), dipeptidyl peptidase-4 inhibitors (DPPIs), meglitinides, and alpha-glucosidase inhibitors (AGIs) could have beneficial effects in the management of TBI complications. These drugs may downregulate the inflammatory pathways and induce antioxidant signaling pathways, thus alleviating complications of TBI.

CONCLUSION

Based on this comprehensive literature review, antidiabetic medications might be considered in the TBI treatment protocol. However, evidence from clinical trials in patients with TBI is still warranted.

Successful use of methylene blue for catecholamine-refractory vasoplegic shock due to metformin intoxication: A case report and literature review

Background

Severe metformin intoxication can lead to lactic acidosis and vasoplegic shock, for which the optimal management strategy remains uncertain, especially in cases of severe circulatory collapse.

Case Presentation

A 45-year-old diabetic woman on metformin therapy presented with impaired consciousness and seizures. She had experienced a cardiac arrest and undergone extracorporeal cardiopulmonary resuscitation. Blood gas analysis showed severe lactic acidosis. A 71-g metformin packet was found at the patient's home, suggesting an overdose. Despite extracorporeal support and blood purification, severe lactic acidosis and hypotension persisted. Methylene blue was administered 32 h from the onset, which improved her metabolic and circulatory status. We examined her blood sample throughout the case to check the transition of metformin blood concentration.

Conclusion

Methylene blue may be beneficial for severe metformin toxicity, regardless of the blood concentration of metformin and the time since intoxication. However, further research is needed to establish its optimal use and effectiveness.

Communal interaction of glycation and gut microbes in diabetes mellitus, Alzheimer's disease, and Parkinson's disease pathogenesis

Diabetes and its complications, Alzheimer's disease (AD), and Parkinson's disease (PD) are increasing gradually, reflecting a global threat vis-à-vis expressing the essentiality of a substantial paradigm shift in research and remedial actions. Protein glycation is influenced by several factors, like time, temperature, pH, metal ions, and the half-life of the protein. Surprisingly, most proteins associated with metabolic and neurodegenerative disorders are generally long-lived and hence susceptible to glycation. Remarkably, proteins linked with diabetes, AD, and PD share this characteristic. This modulates protein's structure, aggregation tendency, and toxicity, highlighting renovated attention. Gut microbes and microbial metabolites marked their importance in human health and diseases. Though many scientific shreds of evidence are proposed for possible change and dysbiosis in gut flora in these diseases, very little is known about the mechanisms. Screening and unfolding their functionality in metabolic and neurodegenerative disorders is essential in hunting the gut treasure. Therefore, it is imperative to evaluate the role of glycation as a common link in diabetes and neurodegenerative diseases, which helps to clarify if modulation of nonenzymatic glycation may act as a beneficial therapeutic strategy and gut microbes/metabolites may answer some of the crucial questions. This review briefly emphasizes the common functional attributes of glycation and gut microbes, the possible linkages, and discusses current treatment options and therapeutic challenges.

Novel Approaches for the Management of Type 2 Diabetes Mellitus: An Update

Diabetes mellitus is an irreversible, chronic metabolic disorder indicated by hyperglycemia. It is now considered a worldwide pandemic. T2DM, a spectrum of diseases initially caused by tissue insulin resistance and slowly developing to a state characterized by absolute loss of secretory action of the β cells of the pancreas, is thought to be caused by reduced insulin secretion, resistance to tissue activities of insulin, or a combination of both. Insulin secretagogues, biguanides, insulin sensitizers, alpha-glucosidase inhibitors, incretin mimetics, amylin antagonists, and sodium-glucose co-transporter-2 (SGLT2) inhibitors are the main medications used to treat T2DM. Several of these medication's traditional dosage forms have some disadvantages, including frequent dosing, a brief half-life, and limited absorption. Hence, attempts have been made to develop new drug delivery systems for oral antidiabetics to ameliorate the difficulties associated with conventional dosage forms. In comparison to traditional treatments, this review examines the utilization of various innovative therapies (such as microparticles, nanoparticles, liposomes, niosomes, phytosomes, and transdermal drug delivery systems) to improve the distribution of various oral hypoglycemic medications. In this review, we have also discussed some new promising candidates that have been approved recently by the US Food and Drug Administration for the treatment of T2DM, like semaglutide, tirzepatide, and ertugliflozin. They are used as a single therapy and also as combination therapy with drugs like metformin and sitagliptin.

Synthesis of GG-g-P(NIPAM-co-AA)/GO and evaluation of adsorption activity for the diclofenac and metformin

The grafting of biopolymer gum ghatti (GG) over the PNIPAM and PAA was done and loaded with graphene oxide (GO). Aim of this work is carried out combine adsorption of sodium diclofenac (SD) and metformin (MF) by the prepared hydrogels under influence of various parameters. The adsorbent GG-g-P(NIPAM-co-PAA)/GO(3 mg) chosen for adsorption activity as it displayed highest swelling capacity. The effect of amount of both adsorbents GG-g-P(NIPAM-co-PAA and GG-g-P(NIPAM-co-PAA)/GO(3 mg) showed that highest adsorption capacity found at 40 mg of adsorbents for both drugs at conditions: 100 mg/L concentration, 30 °C, 24 h and pH 6 and subsequently became stable. Both the drugs were removed in greater amount at 25 mg/L concentration, 24 h of contact time, 30 °C, 40 mg amount of both adsorbents and pH 6. Effect of time revealed that as time elevated from 2 h to 12 (100 mg/L concentration,, 30 °C, 40 mg amount of both adsorbents and pH 6) led to increase adsorption efficiency and after that increase time did not much impact on adsorption activity. Adsorption activity of hydrogels declined with increase of temperature (100 mg/L concentration, 12 h, 40 mg amount of both adsorbents and pH 6). The acidic conditions favored adsorption of SD while MF adsorbed under the weak acidic(100 mg/L concentration, 30 °C, 12 h, 40 mg amount of both adsorbents). However, basic conditions did not much influence on adsorption of MF but effected on adsorption activity of SD. Adsorption isotherm and kinetic model suggested that adsorption is homogenous and chemical in nature. The maximum adsorption capacity (qm) found to be 289.01 and 154.55 mg/g for SD and MF respectively.

Graphical abstract

Supplementary information

The online version contains supplementary material available at 10.1007/s40201-023-00867-w.

Methylene blue as treatment for vasoplegic shock in severe metformin overdose: A case report

Introduction

Severe metformin overdose can result in life-threatening conditions such as metabolic acidosis with hyperlactatemia and vasoplegic shock. Current treatment guidelines recommend hemodialysis and supportive care. However, this case report presents the use of methylene blue as an additional treatment for severe metformin overdose-induced vasoplegic shock, which is not commonly described in the literature or guidelines.

Case report

A 55-year-old woman presented to the emergency department after ingesting 82.5 g of metformin, resulting in severe metabolic acidosis with hyperlactatemia and refractory vasoplegic shock. Despite continuous hemodialysis and high levels of noradrenalin and vasopressin, the shock persisted. Methylene blue was administered, leading to an immediate and persistent reduction in the noradrenalin dose and rapid shock resolution.

Discussion

This case illustrates the potential use of methylene blue in the treatment of severe metformin overdose. The mechanism for metformin-induced vasoplegia is likely mediated by nitric oxide (NO). Methylene blue has been used to treat NO-mediated vasoplegia in other conditions, such as sepsis and poisoning with beta-blockers and calcium channel blockers, but it is rarely described in metformin toxicity. Methylene blue has a rapid onset of action, with only a few mild side effects. This case report emphasizes the need for clinicians to consider methylene blue as a potential treatment option in cases of refractory vasoplegic shock due to severe metformin overdose.

Health impact assessment after Danio rerio long-term exposure to environmentally relevant concentrations of metformin and guanylurea

The antidiabetic drug metformin (MET) and its metabolite guanylurea (GUA) have been frequently and ubiquitously detected in surface water. Consequently, there has been a consistent rise in studying the toxicity of MET and GUA in fish over the past decade. Nonetheless, it is noteworthy that no study has assessed the harmful effects both compounds might trigger on fish blood and organs after chronic exposure. Taking into consideration the data above, our research strived to accomplish two primary objectives: Firstly, to assess the effect of comparable concentrations of MET and GUA (1, 40, 100 μg/L) on the liver, gills, gut, and brain of Danio rerio after six months of flow-through exposure. Secondly, to compare the outcomes to identify which compound prompts more significant oxidative stress and apoptosis in organs and blood parameter alterations. Herein, findings indicate that both compounds induced oxidative damage and increased the expression of genes associated with apoptosis (bax, bcl2, p53, and casp3). Chronic exposure to MET and GUA also generated fluctuations in glucose, creatinine, phosphorus, liver enzymes, red and white blood count, hemoglobin, and hematocrit levels. The observed biochemical changes indicate that MET and GUA are responsible for inducing hepatic damage in fish, whereas hematological alterations suggest that both compounds cause anemia. Considering GUA altered to a more considerable extent the values of all endpoints compared to the control group, it is suggested transformation product GUA is more toxic than MET. Moreover, based on the above evidence, it can be inferred that a six-month exposure to MET and GUA can impair REDOX status and generate apoptosis in fish, adversely affecting their essential organs' functioning.

Clinical efficacy of Huanglian Wendan decoction in treating type 2 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Huanglian Wendan decoction (HLWDD) is a traditional Chinese prescription, which has been used to treat type 2 diabetes mellitus (T2DM) in recent years. However, no studies have evaluated its underlying clinical efficacy. Therefore, we used systematic review and meta-analysis to explore the clinical efficacy of HLWDD in treating T2DM.

METHODS

The randomized controlled trials of HLWDD on T2DM were retrieved from Chinese and foreign databases. The primary outcomes included fasting blood glucose (FBG), 2-hour postprandial blood glucose (2hPG), and glycosylated hemoglobin, type A1c (HbA1c). The secondary outcomes included fasting serum insulin, homeostasis model assessment of insulin resistance (HOMA-IR), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c). Statistical analyses were performed using Review Manager and Stata software. Mean difference (MD) with 95% confidence intervals (CI) were used to describe results. The grades of recommendation assessment, development and evaluation approach was used to rate the quality of the evidence; and trial sequential analysis was used to evaluate the required information size and treatment benefits.

RESULTS

Twenty-three randomized controlled trials were included in this study. We showed that HLWDD can improve FBG (MD = -0.99, 95% CI: -1.10 to -0.88), 2hPG (MD = -1.57, 95% CI: -1.97 to -1.17), HbA1c (MD = -1.11, 95% CI: -1.42 to -0.80), HOMA-IR (MD = -0.80, 95% CI: -1.80 to -0.51), TC (MD = -0.65, 95% CI: -0.88 to -0.42), TG (MD = -0.32, 95% CI: -0.38 to -0.27), LDL-c (MD = -0.54, 95% CI: -0.66 to -0.41), and HDL-c (MD = 0.08, 95% CI: 0.02-0.15) levels in T2DM patients. Trial sequential analysis suggested that the eficacy of HLWDD in improving FBG, 2hPG, HbA1c, HOMA-IR, TC, TG, LDL-c, and HDL-c was sufficient to draw a firm conclusion. Grades of recommendation assessment showed that HLWDD only has high or moderate quality of evidence in improving FBG, and TG.

CONCLUSION

HLWDD can improve blood glucose and blood lipid levels in T2DM patients, and may be a potential drug to treat T2DM.

High risk and low prevalence diseases: Metformin toxicities

INTRODUCTION

Metformin toxicity is a rare but serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of metformin toxicity, including diagnosis, initial resuscitation, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Metformin is a common medication used for treatment of diabetes mellitus. Metformin toxicity is a spectrum of conditions that may be differentiated into three subgroups: metformin-associated lactic acidosis (MALA), metformin-induced lactic acidosis (MILA), and metformin-unrelated lactic acidosis (MULA). MILA is a condition found predominantly in patients chronically taking metformin or those with large acute overdoses. Conversely, MULA occurs in patients on metformin but with a critical illness stemming from a separate cause. MALA is rare but the most severe form, with mortality rates that reach 50%. Differentiating these entities is difficult in the ED setting without obtaining metformin levels. Patients with metformin toxicity present with nonspecific gastrointestinal symptoms and vital sign abnormalities. Laboratory analysis will reveal a high lactate with anion gap metabolic acidosis. Patients presenting with elevated lactate levels in the setting of metformin use should be considered at risk for the most severe form, MALA. Patients with MALA require aggressive treatment with intravenous fluids, treatment of any concomitant condition, and early consideration of hemodialysis, along with specialist consultation such as nephrology and toxicology.

CONCLUSIONS

An understanding of metformin toxicity can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Research Progress of Metformin in the Treatment of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies and has a high mortality, posing a great threat to both human physical and mental health. With the advancement of scientific research, a variety of cancer therapies have been used for OSCC treatment. However, the prognosis of OSCC shows no significant improvement. Metformin has been recognized as the first-line drug for the treatment of diabetes, and recent studies have shown that metformin has a remarkable suppressive effect on tumor progression. Metformin can not only affect the energy metabolism of tumor cells but also play an antitumor role by modulating the tumor microenvironment and cancer stem cells. In this review, the molecular mechanism of metformin and its anticancer mechanism in OSCC are summarized. In addition, this article summarizes the side effects of metformin and the future prospects of its application in the treatment of OSCC.

Metformin may be a viable adjunctive therapeutic option to potentially enhance immune reconstitution in HIV-positive immunological non-responders

ABSTRACT

Incomplete immune reconstitution remains a global challenge for human immunodeficiency virus (HIV) treatment in the present era of potent antiretroviral therapy (ART), especially for those individuals referred to as immunological non-responders (INRs), who exhibit dramatically low CD4 + T-cell counts despite the use of effective antiretroviral therapy, with long-term inhibition of viral replication. In this review, we provide a critical overview of the concept of ART-treated HIV-positive immunological non-response, and also explain the known mechanisms which could potentially account for the emergence of immunological non-response in some HIV-infected individuals treated with appropriate and effective ART. We found that immune cell exhaustion, combined with chronic inflammation and the HIV-associated dysbiosis syndrome, may represent strategic aspects of the immune response that may be fundamental to incomplete immune recovery. Interestingly, we noted from the literature that metformin exhibits properties and characteristics that may potentially be useful to specifically target immune cell exhaustion, chronic inflammation, and HIV-associated gut dysbiosis syndrome, mechanisms which are now recognized for their critically important complicity in HIV disease-related incomplete immune recovery. In light of evidence discussed in this review, it can be seen that metformin may be of particularly favorable use if utilized as adjunctive treatment in INRs to potentially enhance immune reconstitution. The approach described herein may represent a promising area of therapeutic intervention, aiding in significantly reducing the risk of HIV disease progression and mortality in a particularly vulnerable subgroup of HIV-positive individuals.

Type B Lactic Acidosis in a Patient with Mantle Cell Lymphoma

Type B lactic acidosis is an uncommon medical emergency in which acid production overwhelms hepatic clearance. This specific etiology of lactic acidosis occurs without organ hypoperfusion and has been most commonly described in patients with hematologic malignancies but also in patients with solid tumors. The mechanism by which cancer cells switch their glucose metabolism toward increasingly anaerobic glycolytic phenotypes has been described as the "Warburg effect." Without treating the underlying malignancy, the prognosis for patients diagnosed with malignancy-related type B lactic acidosis is extremely poor. Here, we present a case of a 66-year-old male who was diagnosed with type B lactic acidosis secondary to mantle cell lymphoma. Bicarbonate drip was started to correct the lactic acidosis. The patient was also immediately treated with rituximab chemotherapy combined with rasburicase to avoid the hyperuricemia associated with tumor lysis syndrome. He responded to the early treatment and was discharged with normal renal function. Type B lactic acidosis secondary to hematologic malignancy is important to recognize. In order to successfully treat this syndrome, early diagnosis and simultaneous treatment of the imbalance of lactic acid levels and the underlying malignancy are necessary.

Toxicology of pharmaceutical and nutritional longevity compounds

Aging is the most prominent risk factor for many diseases, which is considered to be a complicated biological process. The rate of aging depends on the effectiveness of important mechanisms such as the protection of DNA from free radicals, which protects the structural and functional integrity of cells and tissues. In any organism, not all organs may age at the same rate. Slowing down primary aging and reaching maximum lifespan is the most basic necessity. In this process, it may be possible to slow down or stabilise some diseases by using the compounds for both dietary and pharmacological purposes. Natural compounds with antioxidant and anti-inflammatory effects, mostly plant-based nutraceuticals, are preferred in the treatment of age-related chronic diseases and can also be used for other diseases. An increasing number of long-term studies on synthetic and natural compounds aim to elucidate preclinically and clinically the mechanisms underlying being healthy and prolongation of life. To delay age-related diseases and prolong the lifespan, it is necessary to take these compounds with diet or pharmaceuticals, along with detailed toxicological results. In this review, the most promising and utilised compounds will be highlighted and it will be discussed whether they have toxic effects in short/long-term use, although they are thought to be used safely.

A case of metformin-associated lactic acidosis with cardiogenic and vasoplegic shock supported by ECPella

Metfomin-associated lactic acidosis (MALA) is a rare but life-threatening complication of metformin use. We present a case of MALA with concurrent cardiogenic and vasoplegic shock which was successfully supported by ECPella (concurrent use of VA-ECMO and Impella). Early recognition, aggressive hemodynamic support with ECPella and early hemodialysis can be life-saving. Monitoring of both lactate and SvO2 trends can help understand the response to treatment.

A Case of Metformin-Associated Lactic Acidosis

Metformin is a US FDA-approved oral anti-hyperglycemic medication used to treat non-insulin-dependent diabetes mellitus (NIDDM). Metformin, a biguanide drug, works by reducing glucose production in the liver, decreasing intestinal absorption, and improving insulin sensitivity, leading to lower blood glucose levels. Metformin is generally considered to be a medication with a good safety profile and high tolerability. However, metformin therapy is associated with an uncommon but potentially serious complication known as metformin-associated lactic acidosis (MALA), which is marked by severe lactic acid accumulation in the bloodstream. This case introduces an elderly female with multiple comorbidities who presented with confusion, malaise, and lethargy. Her laboratory findings revealed acute renal failure, severe metabolic acidosis, and significantly elevated lactic acid levels consistent with sepsis and possibly MALA. Aggressive resuscitation with fluids and sodium bicarbonate was initiated. Antimicrobial drugs were started for urinary tract infections. She subsequently required endotracheal intubation with invasive ventilation, pressor support, and continuous renal replacement therapy. Her condition gradually improved over several days. The patient ultimately recovered, and at the time of discharge, metformin was discontinued, and a sodium-glucose cotransporter-2 (SGLT-2) inhibitor was initiated. This case underscores the relevance of MALA as a potential complication of metformin therapy, particularly in patients with underlying kidney disease or other risk factors. Timely detection and prompt management of MALA can prevent progression to a critical stage and thus avoid potentially fatal outcomes.

Adherence to Oral Antidiabetic Drugs in Patients with Type 2 Diabetes: Systematic Review and Meta-Analysis

Poor adherence to oral antidiabetic drugs (OADs) in patients with type 2 diabetes (T2D) can lead to therapy failure and risk of complications. The aim of this study was to produce an adherence proportion to OADs and estimate the association between good adherence and good glycemic control in patients with T2D. We searched in MEDLINE, Scopus, and CENTRAL databases to find observational studies on therapeutic adherence in OAD users. We calculated the proportion of adherent patients to the total number of participants for each study and pooled study-specific adherence proportions using random effect models with Freeman-Tukey transformation. We also calculated the odds ratio (OR) of having good glycemic control and good adherence and pooled study-specific OR with the generic inverse variance method. A total of 156 studies (10,041,928 patients) were included in the systematic review and meta-analysis. The pooled proportion of adherent patients was 54% (95% confidence interval, CI: 51-58%). We observed a significant association between good glycemic control and good adherence (OR: 1.33; 95% CI: 1.17-1.51). This study demonstrated that adherence to OADs in patients with T2D is sub-optimal. Improving therapeutic adherence through health-promoting programs and prescription of personalized therapies could be an effective strategy to reduce the risk of complications.

2,3-Dihydrosorbicillin and chrysopanol stimulate insulin secretion in INS-1 cells

Pancreatic β-cell function and insulin secretion are important in antidiabetic drug development. In an effort to discover small molecules to regulate insulin secretion, an endophytic fungus, Penicillium sp. SSP-1CLG, was selected for chemical investigation. Large scale cultures of the strain followed by extraction and chromatographic analysis led to the isolation of 10 anthraquinone and alkaloid-type compounds. The isolated compounds were identified by comprehensive analysis of NMR, MS, and ECD data. The effect of compounds 1-10 on insulin secretion in INS-1 cells was investigated. 2,3-Dihydrosorbicillin (1), chrysophanol (2), and glandicolin B (10) at non-cytotoxic concentrations resulted in an increase of glucose-stimulated insulin secretion (GSIS) in rat INS-1 pancreatic β-cells. Furthermore, we investigated the signaling pathway involved in 2,3-dihydrosorbicillin (1) and chrysophanol (2) action in the activation of peroxisome proliferator-activated receptor γ (PPARγ), pancreatic and duodenal homeobox-1 (PDX-1), insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3-kinase (PI3K), and Akt. Treatment of INS-1 cells with 2,3-dihydrosorbicillin (1) and chrysophanol (2) increased the expression of these proteins. Our findings indicate that 2,3-dihydrosorbicillin and chrysophanol may play roles in the regulation of insulin secretion in pancreatic β-cells, at least in part, by targeting PPARγ and PDX-1 via the IRS-2/PI3K/Akt signaling pathway.

Therapeutic Effect of Curcumin on Metabolic Diseases: Evidence from Clinical Studies

Metabolic diseases have become a serious threat to human health worldwide. It is crucial to look for effective drugs from natural products to treat metabolic diseases. Curcumin, a natural polyphenolic compound, is mainly obtained from the rhizomes of the genus Curcuma. In recent years, clinical trials using curcumin for the treatment of metabolic diseases have been increasing. In this review, we provide a timely and comprehensive summary of the clinical progress of curcumin in the treatment of three metabolic diseases, namely type 2 diabetes mellitus (T2DM), obesity and non-alcoholic fatty liver disease (NAFLD). The therapeutic effects and underlying mechanisms of curcumin on these three diseases are presented categorically. Accumulating clinical evidence demonstrates that curcumin has good therapeutic potential and a low number of side effects for the three metabolic diseases. It can lower blood glucose and lipid levels, improve insulin resistance and reduce inflammation and oxidative stress. Overall, curcumin may be an effective drug for the treatment of T2DM, obesity and NAFLD. However, more high-quality clinical trials are still required in the future to verify its efficacy and determine its molecular mechanisms and targets.

Action Mechanism of Metformin and Its Application in Hematological Malignancy Treatments: A Review

Hematologic malignancies (HMs) mainly include acute and chronic leukemia, lymphoma, myeloma and other heterogeneous tumors that seriously threaten human life and health. The common effective treatments are radiotherapy, chemotherapy and hematopoietic stem cell transplantation (HSCT), which have limited options and are prone to tumor recurrence and (or) drug resistance. Metformin is the first-line drug for the treatment of type 2 diabetes (T2DM). Recently, studies identified the potential anti-cancer ability of metformin in both T2DM patients and patients that are non-diabetic. The latest epidemiological and preclinical studies suggested a potential benefit of metformin in the prevention and treatment of patients with HM. The mechanism may involve the activation of the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway by metformin as well as other AMPK-independent pathways to exert anti-cancer properties. In addition, combining current conventional anti-cancer drugs with metformin may improve the efficacy and reduce adverse drug reactions. Therefore, metformin can also be used as an adjuvant therapeutic agent for HM. This paper highlights the anti-hyperglycemic effects and potential anti-cancer effects of metformin, and also compiles the in vitro and clinical trials of metformin as an anti-cancer and chemosensitizing agent for the treatment of HM. The need for future research on the use of metformin in the treatment of HM is indicated.

Natural Products as Outstanding Alternatives in Diabetes Mellitus: A Patent Review

Diabetes mellitus (DM) is a metabolic syndrome that can be considered a growing health problem in the world. High blood glucose levels are one of the most notable clinical signs. Currently, new therapeutic alternatives have been tackled from clinicians' and scientists' points of view. Natural products are considered a promising source, due to the huge diversity of metabolites with pharmaceutical applications. Therefore, this review aimed to uncover the latest advances in this field as a potential alternative to the current therapeutic strategies for the treatment of DM. This purpose is achieved after a patent review, using the Espacenet database of the European Patent Office (EPO) (2016-2022). Final screening allowed us to investigate 19 patents, their components, and several technology strategies in DM. Plants, seaweeds, fungi, and minerals were used as raw materials in the patents. Additionally, metabolites such as tannins, organic acids, polyphenols, terpenes, and flavonoids were found to be related to the potential activity in DM. Moreover, the cellular transportation of active ingredients and solid forms with special drug delivery profiles is also considered a pharmaceutical technology strategy that can improve their safety and efficacy. From this perspective, natural products can be a promissory source to obtain new drugs for DM therapy.

Bioequivalence and safety evaluation of two preparations of metformin hydrochloride sustained-release tablets (Boke® and Glucophage®-XR) in healthy Chinese volunteers: a randomized phase I clinical trial

BACKGROUND

As per the National Medical Products Administration (NMPA) requirements, the quality and efficacy of generic drugs must be consistent with those of the innovator drug. We aimed to evaluate the bioequivalence and safety of generic metformin hydrochloride sustained-release (MH-SR) tablets (Boke®) developed by Beijing Wanhui Double-crane Pharmaceutical Co. Ltd., China and the innovator product metformin hydrochloride extended-release tablets (Glucophage®-XR) manufactured by Bristol-Myers Squibb Company, New York, NY, in healthy Chinese volunteers.

MATERIALS AND METHODS

We performed a bioequivalence and safety assessment of MH-SR (500 mg/tablet) and Glucophage®-XR (500 mg/tablet) tablets in a randomized, open-label, two-period, two-sequence crossover, single-dose oral study in 48 healthy Chinese adult participants under fasting conditions (Chinese Clinical Trial Registration No. CTR20171306). The washout period was seven days. Bioequivalence (80.00-125.00%) was assessed using adjusted geometric mean ratios (GMRs) and two-sided 90% confidence intervals (CIs) of the area under the curve (AUC) and maximum concentration (Cmax) for each component.

RESULTS

The 90% CIs of the test/reference preparation for key pharmacokinetic parameters were 97.36-108.30% for AUC0→t, 97.26-108.09% for AUC0→∞ and 96.76-111.37% for Cmax. No severe adverse events (AEs) were observed. However, 38 adverse drug reactions (ADRs) occurred, including metabolic or nutritional conditions (n = 8), infections (n = 2), gastrointestinal conditions (n = 10) and abnormal inspection (n = 18). No significant difference was observed between MH-SR (23 ADRs, 10 participants) and Glucophage®-XR (15 ADRs, 12 participants) (p = .500). Bioequivalence was concluded since the 90% CIs of the main pharmacokinetic parameters were within the equivalence interval (80.00-125.00%).

CONCLUSIONS

MH-SR (500 mg/tablet) and Glucophage®-XR (500 mg/tablet) were found to be bioequivalent and safe under fasting conditions in healthy Chinese participants. Thus, the market demand for MH-SR tablets (500 mg/tablet) can be met using the generic alternative.KEY MESSAGESGeneric MH-SR tablets (500 mg, Beijing Wanhui Double-crane Pharmaceutical Co. Ltd., Beijing, China) and innovator MH-SR tablets (Glucophage®-XR, 500 mg, Bristol-Myers Squibb Company, New York, NY, USA) were bioequivalent and safe in healthy Chinese volunteers under single-dose administration and fasting conditions.The main goal of this study is to support an increase in the supply of MH-SR tablets in China by proving the efficacy and safety of a generic alternative.Although no sugar was administered in the BE trial of the MH-SR tablets under fasting conditions, no hypoglycaemic event occurred. The method used in this study is expected to serve as a reference for BE studies of different MH-SR formulations.

DEVELOPMENT OF MICROCAPSULES BASED ON COMBINED ANTIDIABETIC SUBSTANCE: PHARMACOLOGICAL CHARACTERISTICS

The comparative assessment results of the hypoglycemic activity of a combined preparation containing microcapsules with a phytocomposition consisting of Glycyrrhiza glabra L. extracts, a dry extract of Galega officinalis L., Mentha piperita L., and gliclazide, are discussed in the article. Methods for obtaining microcapsules with an original PEG-6000 shell are described.

The aim of the study was to develop an optimal technology for obtaining microcapsules with a PEG-6000 shell containing a combined antidiabetic substance, and conduct its detailed pharmacological study on the model of type 2 diabetes mellitus, to conduct a detailed comparative pharmacological study of a microencapsulated antidiabetic composition with a shell based on PEG-6000, including gliclazide and a sum of phytoextracts on the model of type 2 diabetes mellitus.

Materials and methods. As the main objects of the study, microcapsules with a PEG-6000 shell were obtained using methyl miristate as the base liquid. The capsules contained the amount of plant extracts in their composition: a dry extract of Glycyrrhiza glabra L., a dry extract of Galega officinalis L., a dry extract of Mentha piperita L., and gliclazide. The study of a hypoglycemic activity was carried out after a single administration of drugs to the animals with alloxan-induced type 2 diabetes mellitus. The cumulative effect assessment of the drugs was carried out within 14 days with a test for the resistance to oral glucose on days 7 and 14.

Results. Microcapsules with the original shell were obtained by dispersion in a liquid-liquid system with the adjustment of some technological stages. The effect of the drugs under study on the glycemic profile in the rats with an experimental model of type 2 diabetes mellitus was investigated. A comparative evaluation of the pharmacological effect was carried out with a separate and combined use of microencapsulated preparations.

Conclusion. The rationality of combining phytocomponents and a synthetic antidiabetic agent in microcapsules has been proven. The obtained results testify to the rationality of plant extracts combination and a synthetic hypoglycemic agent – gliclazide in microcapsules.

Glucose-lowering effects of orally administered superoxide dismutase in type 2 diabetic model rats

Superoxide dismutase (SOD) is an enzyme found in most food sources, might be a candidate to reduce oxidative damage to intestinal barrier, thereby ameliorating the vicious circle between hyperglycemia and the oxidative damage. Here we report the oral administration of SOD, liposome-embedded SOD (L-SOD), and SOD hydrolysate to type 2 diabetic model rats to confirm this hypothesis. Oxidative damage severity in model rat intestine was indicated by malondialdehyde level, GSSG/GSH ratio, and antioxidant enzyme activity. The damage was significantly repaired by L-SOD. Furthermore, blood glucose and related indexes correlated well not only with oxidative damage results but also with indexes indicating physical intestinal damage such as colon density, H&E staining, immunohistochemical analysis of the tight junction proteins occludin and ZO-1 in the colon, as well as lipopolysaccharide and related inflammatory cytokine levels. The order of the magnitude of the effects of these SOD preparations was L-SOD > SOD > SOD hydrolysate. These data indicate that orally administered SOD can exhibit glucose-lowering effect via targeting the intestine of diabetic rats and systemic lipopolysaccharide influx.

Therapeutic Potential of Quercetin in the Management of Type-2 Diabetes Mellitus

Diabetes Mellitus (DM) is a metabolic disorder that is spreading alarmingly around the globe. Type-2 DM (T2DM) is characterized by low-grade inflammation and insulin resistance and is closely linked to obesity. T2DM is mainly controlled by lifestyle/dietary changes and oral antidiabetic drugs but requires insulin in severe cases. Many of the drugs that are currently used to treat DM are costly and present adverse side effects. Several cellular, animal, and clinical studies have provided compelling evidence that flavonoids have therapeutic potential in the management of diabetes and its complications. Quercetin is a flavonoid, present in various natural sources, which has demonstrated in vitro and in vivo antidiabetic properties. It improves oral glucose tolerance, as well as pancreatic β-cell function to secrete insulin. It inhibits the α-glucosidase and DPP-IV enzymes, which prolong the half-life of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Quercetin also suppresses the release of pro-inflammatory markers such as IL-1β, IL-4, IL-6, and TNF-α. Further studies are warranted to elucidate the mode(s) of action of quercetin at the molecular level. This review demonstrates the therapeutic potential of quercetin in the management of T2DM.

Pharmacological effects of polydatin in the treatment of metabolic diseases: A review

BACKGROUND

Metabolic diseases (MDs), a series of chronic disorders, severely decreases the quality of life for patients but also cause a heavy economic burden. Emerging evidence suggests that Polydatin (PD), an important glucoside of resveratrol, is widely distributed in many plants and has shown good therapeutic potential in metabolic diseases.

PURPOSE

To review the PD discovered before 2021 and their potential to treat metabolic diseases. The activities against diabetes, Obesity, atherosclerosis, NAFLD, NASH, hyperlipidemia, and gout with special emphasis on pharmacology, pharmacokinetics, mechanisms of action, possible roles in current medicine, and future perspectives are discussed.

METHODS

A comprehensive search of published literature was conducted to locate original publications pertaining to polydatin and MDs through the end of 2021 using MEDLINE, Elsevier, Springer, PubMed, Scholar, and CNKI databases. The main inquiry used was for the presence of the following keywords in various combinations in the abstracts: 'Polydatin', 'Metabolic diseases', 'Pharmacology', 'Toxicology', 'Pharmacokinetics', 'Diabetes', 'Obesity', 'Atherosclerosis', 'Non-alcoholic fatty liver disease', 'Non-alcoholic steatohepatitis', 'Hyperlipidemia', and 'Gout'.

RESULTS

The search yielded 987 articles, of which 33 articles were included in this review. Studies have revealed that PD can promote insulin secretion, alleviate insulin resistance, regulate glucose and lipid metabolism, reduce liver lipid deposition, inhibit inflammation, oxidative stress, and decrease uric acid deposition in preclinical experiments. The underlying mechanisms of PD in treatment MDs may be attributed to the regulation of multiple signaling pathways, including. NF-κB, AGEs/RAGE, MAPK/ERK, AMPK/LDLR, IRS1/PI3K/AKT, LKB1/AMPK, PPARβ-NO, SIRT1-PGC-1α-SOD2, PKC, etc., The pharmacokinetic profiles of PD provide valuable information on therapeutic efficacy in treating metabolic diseases.

CONCLUSION

This review summarizes the available reports and evidence which support the use of PD as a potential candidate in the treatment of MDs and provides an overview of the modulatory effects of PD in metabolic diseases and cell signaling pathways, which may have important implications in its future clinical use.

Two cases of suspected poisoning with goat's rue (Galega officinalis L.) in horses

The present report describes two novel cases of suspected intoxication with Galega officinalis in a 6- and 21-year-old Arabian mares displaying acute respiratory signs. Both animals showed signs of pulmonary edema at physical examination, with the oldest of the two also manifesting severe dyspnea and foamy nasal discharge. The mares were grazing on the same meadow with hay available ad libitum. Botanical analysis of the latter showed traces of the toxic plant Galega officinalis (L.), which has been daily ingested at a dose of around 14 g of dry matter for three days. Based on the respiratory signs and the presence of goat's rue in the mares' feed, a presumptive diagnosis of plant poisoning was assumed. Dietary change and treatment allowed the 6-year-old mare to fully recover in three days while a longer period of about two weeks was necessary for the older horse. Horses avoid eating fresh goat's rue as its palatability is low, yet poisoning may still happen in these species when the plant is found in dried and processed feed material.

A concealed history behind the disaster: Extremely rare presentations of metformin toxicity in a patient with body dysmorphic disorder

Metformin is a widely used anti-hyperglycemic agent with weight loss effect properties but besides its various utilities, despite being very rare, it has its characteristic toxicity and adverse effects when used in large doses and for the long-term or in patients with renal impairment. We presented here a case of a 36-year-old woman who developed several presentations with diverse features during three years comprising neuropathic symptoms, severe lactic acidosis, three episodes of cardiogenic shock, acute kidney injury, megaloblastic anemia, pancytopenia, and hyponatremia and did not receive a definite diagnosis after each presentation until when she inadvertently disclosed her abuse of extremely unusual doses of metformin during these three years with aim of weight reduction obsessively without knowing that her symptoms could pertain to metformin overdose. She was eventually diagnosed with a body dysmorphic disorder which led to unreasonable abuse of metformin pills that consequently caused its toxicity. Thereafter, with cease of metformin use and psychiatric treatment, her symptoms did not recur and she was doing well after one year of her last admission. Based on the review of the literature, this is the first case of metformin toxicity in a patient with body dysmorphic disorder who was affected with extremely rare features of this intoxication, nevertheless, every manifestation of the patient was discussed exhaustively according to the current and available medical literature.

The Function of Metformin in Aging-Related Musculoskeletal Disorders

Metformin is a widely accepted first-line hypoglycemic agent in current clinical practice, and it has been applied to the clinic for more than 60 years. Recently, researchers have identified that metformin not only has an efficient capacity to lower glucose but also exerts anti-aging effects by regulating intracellular signaling molecules. With the accelerating aging process and mankind’s desire for a long and healthy life, studies on aging have witnessed an unprecedented boom. Osteoporosis, sarcopenia, degenerative osteoarthropathy, and frailty are age-related diseases of the musculoskeletal system. The decline in motor function is a problem that many elderly people have to face, and in serious cases, they may even fail to self-care, and their quality of life will be seriously reduced. Therefore, exploring potential treatments to effectively prevent or delay the progression of aging-related diseases is essential to promote healthy aging. In this review, we first briefly describe the origin of metformin and the aging of the movement system, and next review the evidence associated with its ability to extend lifespan. Furthermore, we discuss the mechanisms related to the modulation of aging in the musculoskeletal system by metformin, mainly its contribution to bone homeostasis, muscle aging, and joint degeneration. Finally, we analyze the protective benefits of metformin in aging-related diseases of the musculoskeletal system.

Prescription Drugs and Mitochondrial Metabolism

Mitochondria are central to the physiology and survival of nearly all eukaryotic cells and house diverse metabolic processes including oxidative phosphorylation, reactive oxygen species buffering, metabolite synthesis/exchange, and Ca2+ sequestration. Mitochondria are phenotypically heterogeneous and this variation is essential to the complexity of physiological function among cells, tissues, and organ systems. As a consequence of mitochondrial integration with so many physiological processes, small molecules that modulate mitochondrial metabolism induce complex systemic effects. In the case of many common prescribed drugs, these interactions may contribute to drug therapeutic mechanisms, induce adverse drug reactions, or both. The purpose of this article is to review historical and recent advances in the understanding of the effects of prescription drugs on mitochondrial metabolism. Specific 'modes' of xenobiotic-mitochondria interactions are discussed to provide a set of qualitative models that aid in conceptualizing how the mitochondrial energy transduction system may be affected. Findings of recent in vitro high-throughput screening studies are reviewed, and a few candidate drug classes are chosen for additional brief discussion (i.e. antihyperglycemics, antidepressants, antibiotics, and antihyperlipidemics). Finally, recent improvements in pharmacokinetic models that aid in quantifying systemic effects of drug-mitochondria interactions are briefly considered.

Distinguishing characteristics of exposure to biguanide and sulfonylurea anti-diabetic medications in the United States

OBJECTIVES

Biguanides and sulfonylureas are anti-hyperglycemic drugs commonly used in the United States. Poisoning with these drugs may lead to serious consequences. The diagnosis of biguanide and sulfonylurea poisoning is based on history, clinical manifestations, and laboratory studies.

METHODS

This study is a six-year retrospective cohort analysis based on the National Poison Data System. Clinical effects of 6183 biguanide and sulfonylurea exposures were identified using binary logistic regression.

RESULTS

The mean age of patients with biguanide and sulfonylurea exposure was 39.27 ± 28.91 and 28.91 ± 30.41 years, respectively. Sulfonylurea exposure is most commonly seen via unintentional exposure, while biguanide exposure frequently occurs as a result of intentional ingestion. Minor and moderate outcomes commonly developed following biguanide and sulfonylurea exposure, respectively. Sulfonylurea exposure was less likely to develop clinical effects abdominal pain, metabolic acidosis, diarrhea, nausea, vomiting, and elevated creatinine than patients ingesting biguanides. However, sulfonylurea exposure was more likely to cause dizziness or vertigo, tremor, drowsiness or lethargy, agitation, diaphoresis, and hypoglycemia.

CONCLUSIONS

Our study is the first to use a wide range of national data to describe the clinical characteristics that differentiate the toxicologic exposure to biguanides and sulfonylureas. Sulfonylurea exposure is commonly seen via unintentional exposure, while metformin exposure is frequently seen via intentional exposure. Sulfonylurea toxicity is more likely to cause agitation, dizziness or vertigo, tremor, diaphoresis, and hypoglycemia, while metformin exposure induces abdominal pain, acidosis, diarrhea, nausea, vomiting, and elevated creatinine.

Biguanide MC001, a Dual Inhibitor of OXPHOS and Glycolysis, Shows Enhanced Antitumor Activity Without Increasing Lactate Production

Metformin and other biguanides represent a new class of inhibitors of mitochondrial complex I that show promising antitumor effects. However, stronger inhibition of mitochondrial complex I is generally associated with upregulation of glycolysis and higher risk of lactic acidosis. Herein we report a novel biguanide derivative, N-cystaminylbiguanide (MC001), which was found to inhibit mitochondrial complex I with higher potency while inducing lactate production to a similar degree as metformin.Furthermore, MC001 was found to efficiently inhibit a panel of colorectal cancer (CRC) cells in vitro and to suppress tumor growth in a HCT116 xenograft nude mouse model, while not enhancing lactate production relative to metformin, exhibiting a superior safety profile to other potent biguanides such as phenformin. Mechanistically, MC001 efficiently inhibits mitochondrial complex I, activates AMPK, and represses mTOR, leading to cell-cycle arrest and apoptosis. Notably, MC001 inhibits both oxidative phosphorylation (OXPHOS) and glycolysis. We therefore propose that MC001 warrants further investigation in cancer treatment.

Biguanide Pharmaceutical Formulations and the Applications of Bile Acid-Based Nano Delivery in Chronic Medical Conditions

Biguanides, particularly the widely prescribed drug metformin, have been marketed for many decades and have well-established absorption profiles. They are commonly administered via the oral route and, despite variation in oral uptake, remain commonly prescribed for diabetes mellitus, typically type 2. Studies over the last decade have focused on the design and development of advanced oral delivery dosage forms using bio nano technologies and novel drug carrier systems. Such studies have demonstrated significantly enhanced delivery and safety of biguanides using nanocapsules. Enhanced delivery and safety have widened the potential applications of biguanides not only in diabetes but also in other disorders. Hence, this review aimed to explore biguanides’ pharmacokinetics, pharmacodynamics, and pharmaceutical applications in diabetes, as well as in other disorders.

Refractory vasodilatory shock secondary to metformin overdose supported with VA ECMO

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Metformin overdose can lead to vasodilatory shock refractory to medical management.

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Extracorporeal circulatory support with venoarterial ECMO is an effective way to manage profound shock associated with metformin overdose.

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We report the highest recorded serum metformin level in the literature to date.

Metformin overdose may result in vasodilatory shock, lactic acidosis and death. Hemodialysis is an effective means of extracorporeal elimination, but may be insufficient in the shock setting. We present a case of a 39 yo male who presented with hypotension, coma, hypoglycemia, and lactate of 6.5 mmol/L after ingesting an unknown medication. Metformin overdose was suspected, and he was started on hemodialysis. He developed profound vasoplegia refractory to high doses of norepinephrine, vasopressin, epinephrine and phenylephrine. Venoarterial extracorporeal membrane oxygenation (VA ECMO) was initiated and he had full recovery. Serum analysis with high resolution liquid chromatography mass spectrometry revealed a metformin level of 678 μg/mL and trazodone level of 2.1 μg/mL. This case is one of only a handful of reported cases of metformin overdose requiring ECMO support, and we report the highest serum metformin levels in the literature to date. We recommend early aggressive hemodialysis and vasopressor support in all suspected cases of metformin toxicity as well as VA ECMO if refractory to these therapies.

Objective

We present a case of vasodilatory shock secondary to metformin overdose requiring venoarterial extracorporeal membrane oxygenation (VA ECMO) support. This case is one of only a handful of reported cases of metformin overdose requiring ECMO support, and we report the highest serum metformin levels in the literature to date.

Data sources

University of San Francisco, Fresno.

Study design

Case report.

Data extraction

Clinical records and high resolution liquid chromatography mass spectroscopy analysis.

Data synthesis

None.

Conclusions

Venoarterial ECMO provided an effective means of hemodynamic support for a patient with severe metformin toxicity.

Multi-target regulation of intestinal microbiota by berberine to improve type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) and its complications are major public health problems that seriously affect the quality of human life. The modification of intestinal microbiota has been widely recognized for the management of diabetes. The relationship between T2DM, intestinal microbiota, and active ingredient berberine (BBR) in intestinal microbiota was reviewed in this paper. First of all, the richness and functional changes of intestinal microbiota disrupt the intestinal environment through the destruction of the intestinal barrier and fermentation/degradation of pathogenic/protective metabolites, targeting the liver, pancreas, visceral adipose tissue (VAT), etc., to affect intestinal health, blood glucose, and lipids, insulin resistance and inflammation. Then, we focus on BBR, which protects the composition of intestinal microbiota, the changes of intestinal metabolites, and immune regulation disorder of the intestinal environment as the therapeutic mechanism as well as its current clinical trials. Further research can analyze the mechanism network of BBR to exert its therapeutic effect according to its multi-target compound action, to provide a theoretical basis for the use of different phytochemical components alone or in combination to prevent and treat T2DM or other metabolic diseases by regulating intestinal microbiota.

AMPK activators for the prevention and treatment of neurodegenerative diseases

INTRODUCTION

As the global population ages at an unprecedented rate, the burden of neurodegenerative diseases is expected to grow. Given the profound impact illness like dementia exert on individuals and society writ large, researchers, physicians, and scientific organizations have called for increased investigation into their treatment and prevention. Both metformin and aspirin have been associated with improved cognitive outcomes. These agents are related in their ability to stimulate AMP kinase (AMPK). Momordica charantia, another AMPK activator, is a component of traditional medicines and a novel agent for the treatment of cancer. It is also being evaluated as a nootropic agent.

AREAS COVERED

This article is a comprehensive review which examines the role of AMPK activation in neuroprotection and the role that AMPK activators may have in the management of dementia and cognitive impairment. It evaluates the interaction of metformin, aspirin, and Momordica charantia, with AMPK, and reviews the literature characterizing these agents' impact on neurodegeneration.

EXPERT OPINION

We suggest that AMPK activators should be considered for the treatment and prevention of neurodegenerative diseases. We identify multiple areas of future investigation which may have a profound impact on patients worldwide.