The Current and Potential Therapeutic Use of Metformin-The Good Old Drug

The Effect of Genetic Variants of SLC22A2 (rs662301 and rs315978) on the response to Metformin in type 2 Saudi diabetic patients

PURPOSE

To investigate the allelic and genotypic frequencies of the two genetic variations, NC_000006.12: g.160275887C > T (rs662301) and NC_000006.12:g.160231826 T > C (rs315978), in the SLC22A2 gene among the Saudi population. The primary goal is to elucidate potential associations with these genetic variations and the response to metformin therapy over 6 months to enhance our knowledge of the genetic basis of Type 2 Diabetes Mellitus (T2DM) and its clinical management in the Saudi population.

MATERIALS/METHODS

76 newly diagnosed T2DM patients, aged 30 to 60, of both sexes and Saudi origin, were treated with metformin monotherapy. Blood samples were collected before and after 6 months of therapy,80 healthy individuals were included as controls. Genomic DNA was extracted. Genotyping of the SLC22A2 genetic variations was performed using TaqMan® SNP Genotyping Assays. Binary logistic regression was utilized to evaluate how certain clinical parameters influence T2DM concerning the presence of SLC22A2 gene variants.

RESULTS

Among these patients, 73.3 % were responders, and 26.7 % were non-responders. For these variants, no statistically significant differences in genotype or allele frequencies were observed between responders and non-responders (p = 0.375 and p = 0.384 for rs662301; p = 0.473 and p = 0.481 for rs315978, respectively). For the SLC22A2 variant rs662301, the C/C genotype was significantly associated with increased T2DM risk with age and elevated HbA1c levels. Similarly, rs315978 revealed higher T2DM susceptibility and HbA1c elevation in C/C genotype carriers, specifically with advancing age compared to individuals with C/T and T/T genotypes.

CONCLUSION

The study offers insights into the genetic landscape of T2DM in Saudi Arabia. Despite the absence of significant associations with treatment response, the study suggests potential age-specific associations, this highlights the complexity of the disease. This research underscores the necessity for expanded research, considering diverse populations and genetic factors, to develop personalized treatment approaches. This study serves as a foundation for future investigations into the Saudi population, recognizing the need for a larger sample size.

Metformin in combination with chemotherapy increases apoptosis in gastric cancer cells and counteracts senescence induced by chemotherapy

Gastric cancer (GC) is the fourth leading cause of cancer death in the world, and there is a demand for new therapeutic agents to treat GC. Metformin has been demonstrated to be an antineoplastic agent in some types of cancer; however, it has not been sufficiently valued in treating GC because the effect of metformin in combination with chemotherapy regimens has not yet been evaluated. The present study aimed to evaluate the mechanisms underlying cell death induced by metformin alone or when combined with chemotherapy. The cytogenetic characteristics of the NCI-N87 cell line were determined by fluorescence in situ hybridization (FISH). To determine viability, the cells were treated with metformin, epirubicin, cisplatin, docetaxel and 5-fluorouracil (individually and at different concentrations). Subsequently, the cells were treated with metformin alone, and in combination with the chemotherapeutic drugs and the epirubicin + cisplatin + 5-fluorouracil, docetaxel + cisplatin + 5-fluorouracil, and cisplatin + 5-fluorouracil regimens. Cell viability, proliferation and mitochondrial membrane potential (ΔΨm) were analyzed by spectrophotometry. Apoptosis, caspase activity and cell cycle progression were assessed by flow cytometry. Finally, light microscopy was used to evaluate senescence and clonogenicity. The results revealed that metformin, alone and when combined with chemotherapy, increased the proportion of apoptotic cells, promoted the loss of ΔΨm, and induced apoptosis through caspase activity in GC cells. Moreover, metformin decreased cell proliferation. In addition, metformin alone did not induce senescence and it counteracted the effects of chemotherapy-induced senescence in GC cells. Additionally, metformin, alone and when combined with chemotherapy, decreased the clonogenic capacity of NCI-N87 GC cells. In conclusion, metformin may increase the effects of chemotherapy on NCI-N87 cell death and could represent an option to improve the treatment of GC.

Metformin enhances the survival ability of ovarian granulosa cells in polycystic ovary syndrome by promoting LINC00548 to suppress androgen receptor/klotho pathway

BACKGROUND

Metformin (Met) has been reported to play the key role in the pathogenesis of polycystic ovary syndrome (PCOS). However, the precise mechanisms underlying the actions of Met in PCOS remain incompletely understood. This study aimed to confirm the mechanism of Met interacting with a long non-coding RNA LINC00548 in PCOS.

METHODS

Ovarian granulosa cells (OGCs) were incubated 500 nM dihydrotestosterone (DHT) to construct PCOS in vitro model and then were treated 20 μM Met. A series of cell experiments including Cell Counting Kit-8, Terminal uridine nucleotide end labeling, and flow cytometry were performed to confirm the changes of OGC survival ability. Quantitative real-time polymerase chain reaction was conducted to determine the levels of LINC00548, whereas Western blotting was applied to determine the levels of androgen receptor (AR) and klotho.

RESULTS

Met improved the cell viability and suppressed cell apoptosis in DHT-treated OGCs. LINC00548 downregulated in DHT-treated OGCs was upregulated by Met, and its overexpression further enhanced the positive effects of Met on the survival ability of DHT-treated OGCs. In addition, Met could induce the upregulation of LINC00548 to suppress the activation of AR/klotho pathway in DHT-treated OGCs.

CONCLUSION

Overall, this study discovers that Met enhances the survival ability of OGCs in PCOS by elevating LINC00548 expression to suppress AR/klotho pathway.

Transcriptome-Guided Characterization of the Environmental Toxicity of Metformin: Disruption of Energy Homeostasis and Inhibition of Embryonic Development of Zebrafish at Environmentally Relevant Concentrations

Metformin has been widely detected in aquatic ecosystems, yet the knowledge of its impact on aquatic organisms, particularly at environmentally relevant concentrations, remains limited. In the present study, we characterized the developmental toxicity of metformin in zebrafish, utilizing a transcriptome-guided toxicological assessment framework. Transcriptomic analysis conducted at metformin concentrations within the μg/L range revealed significant disruptions in biological processes associated with nucleotide, hydrocarbon, and amino acid metabolism, suggesting a significant disturbance in energy homeostasis. This observation was corroborated by energy-targeted metabolomic analysis, wherein a considerable number of metabolites involved in purine metabolism, pyrimidine metabolism, and the citrate cycle displayed significant alterations. Notably, most intermediates in the citrate cycle such as acetyl-CoA exhibited remarkable decreases. Additionally, our study identified significant impediments in zebrafish embryonic development, including decreased yolk extension progress, spontaneous contraction and body length, and increased yolk sac area and yolk/while body lipid content ratio, at metformin concentrations as low as 0.12 μg/L. Furthermore, the disruption of energy homeostasis by metformin was observed to persist into adulthood even after a prolonged recovery period. The present findings highlighted the disruptive effects of metformin on energy homeostasis and embryonic development in teleost at environmentally relevant concentrations, thereby prompting a reevaluation of its environmental risk to nontarget aquatic organisms.

Metformin-associated lactic acidosis: a serious complication of a common drug

Metformin-associated lactic acidosis (MALA) is a rare and potentially life-threatening complication of metformin use. It typically occurs in patients who are diabetic and also have other risk factors for lactic acidosis, including kidney and liver conditions, malignancy, or use of certain medications. We report a case of MALA in a man in his 70s with diabetes who presented with gradually worsening gastrointestinal symptoms, including severe abdominal pain and nausea. He reported these symptoms in the setting of metformin use with an acute kidney injury (AKI), likely brought on by poor oral intake and excessive antibiotic use for a urinary tract infection. He was promptly started on intravenous fluids with a bicarbonate drip to concurrently treat his prerenal AKI and lactic acidosis, which resulted in rapid resolution of his symptoms. Renal function normalised within 12 days of admission. Since diabetic patients commonly use metformin and are also at higher risk of renal dysfunction, this case highlights the vulnerability of this group of patients and the need for increased knowledge and awareness of MALA.

Is it time to revise the fighting strategy toward type 2 diabetes? Sex and pollution as new risk factors

Diabetes mellitus, a metabolic condition affecting around 537 million individuals worldwide, poses significant challenges, particularly among the elderly population. The etiopathogenesis of type 2 diabetes (T2D) depends on a combination of the effects driven by advancing age, genetic background, and lifestyle habits, e.g. overnutrition. These factors influence the development of T2D differently in men and women, with an obvious sexual dimorphism possibly underlying the diverse clinical features of the disease in different sexes. More recently, environmental pollution, estimated to cause 9 million deaths every year, is emerging as a novel risk factor for the development of T2D. Indeed, exposure to atmospheric pollutants such as PM2.5, O3, NO2, and Persistent Organic Pollutants (POP)s, along with their combination and bioaccumulation, is associated with the development of T2D and obesity, with a 15 % excess risk in case of exposure to very high levels of PM2.5. Similar data are available for plasticizer molecules, e.g. bisphenol A and phthalates, emerging endocrine-disrupting chemicals. Even though causality is still debated at this stage, preclinical evidence sustains the ability of multiple pollutants to affect pancreatic function, promote insulin resistance, and alter lipid metabolism, possibly contributing to T2D onset and progression. In addition, preclinical findings suggest a possible role also for plastic itself in the development of T2D. Indeed, pioneeristic studies evidenced that micro- or nanoplastics (MNP)s, particles in the micro- or nano- range, promote cellular damage, senescence, inflammation, and metabolic disturbances, leading to insulin resistance and impaired glucose metabolism in animal and/or in vitro models. Here we synthesize recent knowledge relative to the association between air-related or plastic-derived pollutants and the incidence of T2D, discussing also the possible mechanistic links suggested by the available literature. We then anticipate the need for future studies in the field of candidate therapeutic strategies limiting pollution-induced damage in preclinical models, such as SGLT-2 inhibitors. We finally postulate that future guidelines for T2D prevention should consider pollution and sex an additional risk factors to limit the diabetes pandemic.

Energy Metabolism and Metformin: Effects on Ischemia-Reperfusion Injury in Kidney Transplantation

Metformin (MTF) is the only biguanide included in the World Health Organization's list of essential medicines; representing a widespread drug in the management of diabetes mellitus. With its accessibility and affordability being one of its biggest assets, it has become the target of interest for many trying to find alternative treatments for varied pathologies. Over time, an increasing body of evidence has shown additional roles of MTF, with unexpected interactions of benefit in other diseases. Metformin (MTF) holds significant promise in mitigating ischemia-reperfusion injury (IRI), particularly in the realm of organ transplantation. As acceptance criteria for organ transplants expand, IRI during the preservation phase remain a major concern within the transplant community, prompting a keen interest in MTF's effects. Emerging evidence suggests that administering MTF during reperfusion may activate the reperfusion injury salvage kinase (RISK) pathway. This pathway is pivotal in alleviating IRI in transplant recipients, potentially leading to improved outcomes such as reduced rates of organ rejection. This review aims to contextualize MTF historically, explore its current uses, pharmacokinetics, and pharmacodynamics, and link these aspects to the pathophysiology of IRI to illuminate its potential future role in transplantation. A comprehensive survey of the current literature highlights MTF's potential to recondition and protect against IRI by attenuating free radical damage, activating AMP-activated protein kinase to preserve cellular energy and promote repair, as well as directly reducing inflammation and enhancing microcirculation.

Beneficial effects of metformin treatment on memory impairment

Memory issues are a prevalent symptom in different neurodegenerative diseases and can also manifest in certain psychiatric conditions. Despite limited medications approved for treating memory problems, research suggests a lack of sufficient options in the market. Studies indicate that a significant percentage of elderly individuals experience various forms of memory disorders. Metformin, commonly prescribed for type 2 diabetes, has shown neuroprotective properties through diverse mechanisms. This study explores the potential of metformin in addressing memory impairments. The current research gathered its data by conducting an extensive search across electronic databases including PubMed, Web of Science, Scopus, and Google Scholar. Previous research suggests that metformin enhances brain cell survival and memory function in both animal and clinical models by reducing oxidative stress, inflammation, and cell death while increasing beneficial neurotrophic factors. The findings of the research revealed that metformin is an effective medication for enhancing various types of memory problems in numerous studies. Given the rising incidence of memory disorders, it is plausible to utilize metformin, which is an affordable and accessible drug. It is often recommended as a treatment to boost memory.

Management of Cardiovascular Risk in the Non-alcoholic Fatty Liver Disease Setting

Non-alcoholic fatty liver disease (NAFLD) is an overlooked and undetected pathology, which affects more than 32% of adults worldwide. NAFLD is becoming more common in Western industrialised countries, particularly in patients with central obesity, type 2 diabetes, dyslipidaemia and metabolic syndrome. Although NAFLD has traditionally been interpreted as a liver disease with a high risk of liver-related complications, NAFLD is an underappreciated and independent risk factor for atherosclerotic cardiovascular disease, which is the principal cause of death in patients with NAFLD. Treatment options to counteract both the progression and development of cardiovascular disease and NAFLD include lifestyle interventions, such as weight loss, increased physical activity and dietary modification, and optimal medical therapy of comorbid conditions; nevertheless, further studies are needed to define optimal treatment strategies for the prevention of both hepatic and cardiovascular complications of NAFLD.

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.

Efficacy of metformin on different adipocytokines in type 2 diabetes mellitus patients

Background

Type 2 diabetes mellitus is a major medical condition that constitutes a significant financial burden on most healthcare systems.

Objective

The current research aimed to evaluate the antidiabetic, anti-inflammatory, and antihyperlipidemic effects of 500 mg metformin twice daily for 6 months on various adipocytokines in type 2 diabetes mellitus patients.

Patients and methods

The participants in this study were divided into three groups: the control, the untreated diabetic, and the metformin-treated diabetic groups.

Results and conclusion

Metformin treatment significantly improved the poor oral glucose tolerance and the lowered serum levels of insulin and C-peptide with subsequent better homeostatic model assessment for insulin resistance and sensitivity and β-cell function results. Moreover, metformin treatment significantly decreased the elevated serum levels of glycosylated hemoglobin, high, low, and very low-density lipoproteins, adipokines (visfatin and resistin), and retinol-binding protein-4 expression, with a significant increase in total cholesterol and triglycerides. Metformin also reduced the proinflammatory cytokine expressions (interleukin-1β, interferon-γ, and tumor-necrosis factor-α). In conclusion, metformin can alleviate adipocytokines through anti-inflammatory effects, synergizing with its antidiabetic actions.

An effective treatment approach of liposomally encapsulated metformin in colon cancer

Metformin is a drug that is widely used in the treatment of type-2 diabetes and its anticarcinogenic effect has been detected in many studies since the 2000s. Metformin has a short half-life and poor biocompatibility, which limits the activity of the drug. As a solution to this situation, our study aimed to increase the anticarcinogenic effects and reduce the side effects of metformin in colon cancer by liposomal encapsulation. For this purpose, in our study, liposome production was carried out using the thin film hydration method. The amount of metformin loaded in liposomes was determined by a standard absorbance curve at 237 nm. Size distributions and membrane zeta potentials of the liposomes were evaluated with Malvern Zetasizer ZS90. Transmission electron microscopy was performed by staining the liposomes negatively with uranyl acetate. Cultured HT-29 cells were treated with liposomal metformin or free metformin at concentrations of 0, 10, 20, and 40 mM for 24 and 48 h. At the end of the treatment period, cell viability was evaluated by CellTiter-Glo luminescent cell viability test. The anticarcinogenic effects of liposomal and free metformin on HT-29 cells were compared. As a result, liposome encapsulated metformin treatment for 24 h was more effective on HT-29 cells at 20- and 40-mM concentrations causing significantly greater decrease in the IC-50 dose compared to the free metformin. The result suggests that liposomal encapsulated metformin may offer a promising approach to increase the efficacy of the drug in the treatment of colon cancer.

TorS - Reframing a rational for type 2 diabetes treatment

The mammalian target of rapamycin complex 1 syndrome (Tors), paradigm implies an exhaustive cohesive disease entity driven by a hyperactive mTORC1, and which includes obesity, type 2 diabetic hyperglycemia, diabetic dyslipidemia, diabetic cardiomyopathy, diabetic nephropathy, diabetic peripheral neuropathy, hypertension, atherosclerotic cardiovascular disease, non-alcoholic fatty liver disease, some cancers, neurodegeneration, polycystic ovary syndrome, psoriasis and other. The TorS paradigm may account for the efficacy of standard-of-care treatments of type 2 diabetes (T2D) in alleviating the glycaemic and non-glycaemic diseases of TorS in T2D and non-T2D patients. The TorS paradigm may generate novel treatments for TorS diseases.

Comparison of SGLT1, SGLT2, and Dual Inhibitor biological activity in treating Type 2 Diabetes Mellitus

Diabetes Mellitus Type 2 (T2D) is an emerging health burden in the USand worldwide, impacting approximately 15% of Americans. Current front-line therapeutics for T2D patients include sulfonylureas that act to reduce A1C and/or fasting blood glucose levels, or Metformin that antagonizes the action of glucagon to reduce hepatic glucose production. Next generation glucomodulatory therapeutics target members of the high-affinity glucose transporter Sodium-Glucose-Linked-Transporter (SGLT) family. SGLT1 is primarily expressed in intestinal epithelium, whose inhibition reduces dietary glucose uptake, whilst SGLT2 is highly expressed in kidney - regulating glucose reabsorption. A number of SGLT2 inhibitors are FDA approved whilst SGLT1 and dual SGLT1 & 2 inhibitor are currently in clinical trials. Here, we discuss and compare SGLT2, SGLT1, and dual inhibitors' biochemical mechanism and physiological effects.

Restoring autophagic function: a case for type 2 diabetes mellitus drug repurposing in Parkinson's disease

Parkinson's disease (PD) is a predominantly idiopathic pathological condition characterized by protein aggregation phenomena, whose main component is alpha-synuclein. Although the main risk factor is ageing, numerous evidence points to the role of type 2 diabetes mellitus (T2DM) as an etiological factor. Systemic alterations classically associated with T2DM like insulin resistance and hyperglycemia modify biological processes such as autophagy and mitochondrial homeostasis. High glucose levels also compromise protein stability through the formation of advanced glycation end products, promoting protein aggregation processes. The ability of antidiabetic drugs to act on pathways impaired in both T2DM and PD suggests that they may represent a useful tool to counteract the neurodegeneration process. Several clinical studies now in advanced stages are looking for confirmation in this regard.

Effect of Metformin Use on Vitamin B12 Deficiency Over Time (EMBER): A Real-World Evidence Database Study

OBJECTIVE

To examine the extent to which metformin increases the risk of vitamin B12 deficiency and borderline deficiency over time in participants with type 2 diabetes mellitus (T2DM).

METHODS

Using the All of Us database, adults aged ≥18 years with T2DM and a documented history of metformin use were included for the evaluation of B12 deficiency. Those with B12 deficiency before metformin use were excluded. Adjusted logistic regression models were used to evaluate the association between metformin use and long-term metformin use (≥4 years) and the risk of B12 deficiency. We conducted a subgroup analysis comparing differences in borderline B12 deficiency in metformin and non-metformin users.

RESULTS

Of 36 740 participants with T2DM, 6221 (16.9%) had documented metformin use. The mean age of metformin users was 65.3 years. B12 deficiency was confirmed in 464 (7.5%) metformin users, and 1919 of 30 519 participants (6.3%) did not use metformin. Metformin users had a 4.7% increased risk of developing B12 deficiency compared with nonmetformin users (P = .44). Each additional year of metformin use was associated with 5% increased likelihood of deficiency (P < .05). Metformin use for ≥4 years resulted in a 41.0% increased odds of B12 deficiency, compared with those who used <4 years of metformin (P < .05). Metformin use increased the odds of borderline B12 deficiency by 27.0% (P < .05).

CONCLUSION

Long-term metformin use was associated with an increased risk of B12 deficiency in patients with T2DM, with compounding risk over time.

Mechanisms of Regulation of the Expression of miRNAs and lncRNAs by Metformin in Ovarian Cancer

Ovarian cancer (OC) is one of the most lethal gynecological malignancies. The use of biological compounds such as non-coding RNAs (ncRNAs) is being considered as a therapeutic option to improve or complement current treatments since the deregulation of ncRNAs has been implicated in the pathogenesis and progression of OC. Old drugs with antitumoral properties have also been studied in the context of cancer, although their antitumor mechanisms are not fully clear. For instance, the antidiabetic drug metformin has shown pleiotropic effects in several in vitro models of cancer, including OC. Interestingly, metformin has been reported to regulate ncRNAs, which could explain its diverse effects on tumor cells. In this review, we discuss the mechanism of epigenetic regulation described for metformin, with a focus on the evidence of metformin-dependent microRNA (miRNAs) and long non-coding RNA (lncRNAs) regulation in OC.

Insights Into Metformin XR Pharmacotherapy Knowledge Among Community Pharmacists: A Cross-Sectional Study

Background

There is a little knowledge on the extent to which healthcare providers understand and accept the professional recommendations and appropriate dosing strategy regarding metformin XR.

Objectives

To evaluate UAE community pharmacists' knowledge, attitude, and practices (KAP) concerning metformin XR.

Methods

This is a cross-sectional research study conducted amongst licensed community pharmacists. The survey took place via a questionnaire and physical interviews were held. The survey used in this study included questions on demographics and questions on the participants' attitudes, knowledge and practices concerning metformin XR. The factors influencing KAP regarding metformin XR were examined via simple logistic regression analysis.

Results

Threehundred fifty-three (n = 353) participants were recruited in the study. Independent pharmacies constituted 57.5% of this study sample and 42.5% were chain pharmacies. The average knowledge score about metformin XR tablets was 42.5% with a confidence interval (CI) of 95% [37.3%, 47.4]. Better knowledge scores on metformin XR tablets was observed in respondents aged ⩾40 years (OR 2.97, 95% CI 1.63-5.4), having greater than 10 years in terms of experience (OR 2.28; 95% CI 1.25-4.16) and pharmacist graduated from Regional or international universities (OR 2.08; 95% CI 1.34-3.24). About 78% (n = 275) of the participants believed that metformin XR tablets have better efficacy and 63.2% (n = 233) indicated that metformin IR was associated with greater adverse effects.

Conclusion

This study demonstrated a distinct gap in knowledge, attitude and practice pertaining to metformin XR among community pharmacists in the UAE. The community pharmacists need to enhance their practice by receiving accurate and reliable data to support their decision-making on the prescribing of metformin XR. The implementation of novel guidelines and evidence dissemination strategies may help bridge this gap.

Depiction of Branched-Chain Amino Acids (BCAAs) in Diabetes with a Focus on Diabetic Microvascular Complications

Type 2 diabetes mellitus (T2DM) still holds the title as one of the most debilitating chronic diseases with rising prevalence and incidence, including its complications such as retinal, renal, and peripheral nerve disease. In order to develop novel molecules for diagnosis and treatment, a deep understanding of the complex molecular pathways is imperative. Currently, the existing agents for T2DM treatment target only blood glucose levels. Over the past decades, specific building blocks of proteins-branched-chain amino acids (BCAAs) including leucine, isoleucine, and valine-have gained attention because they are linked with insulin resistance, pre-diabetes, and diabetes development. In this review, we discuss the hypothetical link between BCAA metabolism, insulin resistance, T2DM, and its microvascular complications including diabetic retinopathy and diabetic nephropathy. Further research on these amino acids and their derivates may eventually pave the way to novel biomarkers or therapeutic concepts for the treatment of diabetes and its accompanied complications.

Canagliflozin + metformin ER for the treatment of type 2 diabetes: the evidence to date

INTRODUCTION

Patients with type 2 diabetes (T2D) usually show progressive deterioration in glycemic control and sequential additions of therapy are generally needed. Many new options for glucose lowering therapy have been introduced recently and it is becoming common practice to use fixed-dose combinations (FDCs) of glucose lowering agents from different classes. This article reviews the FDC of canagliflozin with metformin extended release.

AREAS COVERED

A literature search was performed to identify publications describing the efficacy and safety of canagliflozin and metformin when used separately and in combinations.

EXPERT OPINION

Canagliflozin is a sodium-glucose cotransporter-2 (SGLT2) inhibitor which has shown benefits in reducing progression of renal disease and heart failure in patients with T2D. There was an increased incidence of amputation with canagliflozin in one study, but canagliflozin results in weight loss and reduction of blood pressure which contribute to the overall benefit. Metformin has been the first line oral hypoglycemic agent for many years and is thought to have many advantages, but it should be avoided in patients with severely decreased renal function because of the risk of lactic acidosis. The combination in a single tablet given once daily should help to simplify therapy and improve medication adherence in T2D.

The Influence of Insulin Resistance on Outcomes in Hospitalizations for Alcohol-Related Liver Disease: A Nationwide Study

Background Alcoholic liver disease (ALD) is known to contribute to the onset of insulin resistance (IR), which has been speculated to worsen the outcome of the disease. This study examines the impact of IR on the severity and outcomes of hospitalizations for ALD. Methods A retrospective study was performed using the combined 2016 to 2018 Nationwide Inpatient Sample. All admissions for ALD were included. The association between IR and the clinical and resource utilization of hospitalizations for ALD was analyzed using multivariate regression models to adjust for confounding variables. Results About 294,864 hospitalizations for ALD were analyzed. Of these, 383 cases (0.13%) included a secondary diagnosis of IR, while the remaining 294,481 hospitalizations (99.87%) were considered as controls. The incidence of IR in the study was 1.3 per 1000 admissions for ALD. IR was not associated with any significant difference in the likelihood of mortality (adjusted odds ratio (aOR): 1.10, 95% confidence interval (CI): 0.370-3.251, p=0.867), acute liver failure, or the incidence of complications (aOR: 0.83, 95% CI: 0.535-1.274, p<0.001). However, the study found that ALD hospitalizations with IR had longer hospital stays (7.3 days vs. 6.0 days: IRR, 1.17; 95% CI, 1.09-1.26; p<0.001) and higher mean hospital costs ($91,124 vs. $65,290: IRR, 1.32; 95% CI, 1.20-1.46; p<0.001) compared to patients without IR. Conclusion IR alone does not worsen the outcomes of patients with ALD, and its association with longer hospital stays and higher mean hospital costs could be due to other confounding factors.

Pharmacometabolomic Approach to Investigate the Response to Metformin in Patients with Type 2 Diabetes: A Cross-Sectional Study

Metformin constitutes the foundation therapy in type 2 diabetes (T2D). Despite its multiple beneficial effects and widespread use, there is considerable inter-individual variability in response to metformin. Our objective is to identify metabolic signatures associated with poor and good responses to metformin, which may improve our ability to predict outcomes for metformin treatment. In this cross-sectional study, clinical and metabolic data for 119 patients with type 2 diabetes taking metformin were collected from the Qatar Biobank. Patients were empirically dichotomized according to their HbA1C levels into good and poor responders. Differences in the level of metabolites between these two groups were compared using orthogonal partial least square discriminate analysis (OPLS-DA) and linear models. Good responders showed increased levels of sphingomyelins, acylcholines, and glutathione metabolites. On the other hand, poor responders showed increased levels of metabolites resulting from glucose metabolism and gut microbiota metabolites. The results of this study have the potential to increase our knowledge of patient response variability to metformin and carry significant implications for enabling personalized medicine.

Progranulin is an FMRP target that influences macroorchidism but not behaviour in a mouse model of Fragile X Syndrome

A growing body of evidence has implicated progranulin in neurodevelopment and indicated that aberrant progranulin expression may be involved in neurodevelopmental disease. Specifically, increased progranulin expression in the prefrontal cortex has been suggested to be pathologically relevant in male Fmr1 knockout (Fmr1 KO) mice, a mouse model of Fragile X Syndrome (FXS). Further investigation into the role of progranulin in FXS is warranted to determine if therapies that reduce progranulin expression represent a viable strategy for treating patients with FXS. Several key knowledge gaps remain. The mechanism of increased progranulin expression in Fmr1 KO mice is poorly understood and the extent of progranulin's involvement in FXS-like phenotypes in Fmr1 KO mice has been incompletely explored. To this end, we have performed a thorough characterization of progranulin expression in Fmr1 KO mice. We find that the phenomenon of increased progranulin expression is post-translational and tissue-specific. We also demonstrate for the first time an association between progranulin mRNA and FMRP, suggesting that progranulin mRNA is an FMRP target. Subsequently, we show that progranulin over-expression in Fmr1 wild-type mice causes reduced repetitive behaviour engagement in females and mild hyperactivity in males but is largely insufficient to recapitulate FXS-associated behavioural, morphological, and electrophysiological abnormalities. Lastly, we determine that genetic reduction of progranulin expression on an Fmr1 KO background reduces macroorchidism but does not alter other FXS-associated behaviours or biochemical phenotypes.

Effect of clinical treatments for metabolic syndrome on albuminuria: a systematic review protocol

Introduction: Metabolic syndrome (MetS) predicts cardiovascular disease, and patients with this condition and type 2 diabetes have increased albuminuria, significantly impacting cardiovascular mortality and kidney disease progression. A considerable number of interventions to control MetS exist and are considered efficient, including the use of medication and changes in lifestyle. However, which approaches are effective in controlling albuminuria remains unclear. This systematic review protocol aims to map in the available literature whether lifestyle, medication, and surgical intervention for MetS have an impact on reducing albuminuria in adult patients. Methods: The Joanna Briggs Institute methodology for systematic reviews will be followed. Cochrane Database of Systematic Reviews, Scopus, Embase, and MEDLINE/PubMed databases will be used. For the Gray Literature, the DART-Europe E-theses Portal. There will be no language restriction. Studies written after 2009 will be included due to the consensus and definition of metabolic syndrome. This review will include studies considering pharmacological and non-pharmacological treatments for controlling albuminuria in patients with MetS. Studies where MetS is described in children and adolescents, animals, pregnant women, and patients with type 1 diabetes will be excluded. First, the selection will be based on reading the title and summary of the texts retrieved in the search strategy, followed by reading the relevant texts in full by two reviewers. After the selection of the studies, the extraction of the data, analysis, and synthesis will be conducted according to the JBI methodology.

Venom Peptides, Polyphenols and Alkaloids: Are They the Next Antidiabetics That Will Preserve β-Cell Mass and Function in Type 2 Diabetes?

Improvement of insulin secretion by pancreatic β-cells and preservation of their mass are the current challenges that future antidiabetic drugs should meet for achieving efficient and long-term glycemic control in patients with type 2 diabetes (T2D). The successful development of glucagon-like peptide 1 (GLP-1) analogues, derived from the saliva of a lizard from the Helodermatidae family, has provided the proof of concept that antidiabetic drugs directly targeting pancreatic β-cells can emerge from venomous animals. The literature reporting on the antidiabetic effects of medicinal plants suggests that they contain some promising active substances such as polyphenols and alkaloids, which could be active as insulin secretagogues and β-cell protectors. In this review, we discuss the potential of several polyphenols, alkaloids and venom peptides from snake, frogs, scorpions and cone snails. These molecules could contribute to the development of new efficient antidiabetic medicines targeting β-cells, which would tackle the progression of the disease.

Diabetes mellitus impairs bone regeneration and biomechanics

BACKGROUND

With the rise of high-calorie diets and the aging of populations, the incidence of diabetes was increased dramatically in the world and the number of people with diabetes was predicted to rise to 600 million by 2045. Numerous studies have confirmed that several organ systems, including the skeletal system, are seriously affected by diabetes. In that study, the bone regeneration and the biomechanics of the newly regenerated bone were investigated in diabetic rats, which may provide a supplement for previous studies.

METHODS

A total of 40 SD rats were randomly divided into the type 2 diabetes mellitus (T2DM) group (n = 20) and the control group (n = 20). Beyond that high fat diet and streptozotocin (STZ) were jointly used in the T2DM group, there were no differences between the two groups in terms of treatment conditions. Distraction osteogenesis was used in all animals for the next experimental observation. The evaluation criterion of the regenerated bone was based on radioscopy (once a week), micro-computed tomography (CT), general morphology, biomechanics (including ultimate load, modulus of elasticity, energy to failure, and stiffness), histomorphometry (including von Kossa, Masson trichrome, Goldner trichrome, and safranin O staining), and immunohistochemistry.

RESULTS

All rats in the T2DM group with fasting glucose levels (FGL, > 16.7 mmol/L) were allowed to complete the following experiments. The results showed that rats with T2DM have a higher body weight (549.01 g ± 31.34 g) than rats in the control group (488.60 g ± 33.60 g) at the end of observation. Additionally, compared to the control group, slower bone regeneration in the distracted segments was observed in the T2DM group according to radiography, micro-CT, general morphology, and histomorphometry. Furthermore, a biomechanical test showed that there was a worse ultimate load (31.01 ± 3.39%), modulus of elasticity (34.44 ± 5.06%), energy to failure (27.42 ± 5.87%), and stiffness (34.55 ± 7.66%) than the control group (45.85 ± 7.61%, 54.38 ± 9.33%, 59.41 ± 10.96%, and 54.07 ± 9.30%, respectively). Furthermore, the decreased expressions of hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) were presented in T2DM group by immunohistochemistry.

CONCLUSION

The present study demonstrated that diabetes mellitus impairs bone regeneration and biomechanics in newly regenerated bone, a phenomenon that might be related to oxidative stress and poor angiogenesis brought on by the disease.

Metformin and long non-coding RNAs in breast cancer

Breast cancer (BC) is the second most common cancer and cause of death in women. In recent years many studies investigated the association of long non-coding RNAs (lncRNAs), as novel genetic factors, on BC risk, survival, clinical and pathological features. Recent studies also investigated the roles of metformin treatment as the firstline treatment for type 2 diabetes (T2D) played in lncRNAs expression/regulation or BC incidence, outcome, mortality and survival, separately. This comprehensive study aimed to review lncRNAs associated with BC features and identify metformin-regulated lncRNAs and their mechanisms of action on BC or other types of cancers. Finally, metformin affects BC by regulating five BC-associated lncRNAs including GAS5, HOTAIR, MALAT1, and H19, by several molecular mechanisms have been described in this review. In addition, metformin action on other types of cancers by regulating ten lncRNAs including AC006160.1, Loc100506691, lncRNA-AF085935, SNHG7, HULC, UCA1, H19, MALAT1, AFAP1-AS1, AC026904.1 is described.

Results From a Randomized, Open-Label, Crossover Study Evaluating the Effect of the Aldosterone Synthase Inhibitor Baxdrostat on the Pharmacokinetics of Metformin in Healthy Human Subjects

BACKGROUND

Due to the high comorbidity of diabetes and hypertension, co-administration of metformin with anti-hypertensive drugs is likely. Baxdrostat is an aldosterone synthase inhibitor in development for the potential treatment of hypertension. In vitro data indicated that baxdrostat inhibits the multidrug and toxin extrusion 1 (MATE1) and MATE2-K renal transporters. Metformin is a MATE substrate, so this study assessed potential effects of baxdrostat on the pharmacokinetics of metformin.

METHODS

Twenty-seven healthy volunteers received 1000 mg metformin alone and 1000 mg metformin in the presence of 10 mg baxdrostat in a randomized, crossover manner. Each treatment was separated by 10 or more days. Blood and urine samples were collected over a 3-day period after each treatment to measure plasma and urine concentrations of metformin. Safety was assessed by adverse events (AEs), physical examinations, electrocardiograms, vital signs, and clinical laboratory evaluations.

RESULTS

There were no deaths, serious AEs, discontinuations due to treatment-emergent AEs, or noteworthy increases in AEs with either treatment, indicating that metformin and baxdrostat were well-tolerated when co-administered. Baxdrostat did not significantly affect plasma concentrations or renal clearance of metformin.

CONCLUSION

The results of this study suggest that diabetic patients with hypertension receiving both metformin and baxdrostat are unlikely to require dose adjustment.

REGISTRATION

ClinicalTrials.gov identifier no. NCT05526690.

Phosphoproteomic analysis of metformin signaling in colorectal cancer cells elucidates mechanism of action and potential therapeutic opportunities

BACKGROUND

The biguanide drug metformin is a safe and widely prescribed drug for type 2 diabetes. Interestingly, hundreds of clinical trials have been set to evaluate the potential role of metformin in the prevention and treatment of cancer including colorectal cancer (CRC). However, the "metformin signaling" remains controversial.

AIMS AND METHODS

To interrogate cell signaling induced by metformin in CRC and explore the druggability of the metformin-rewired phosphorylation network, we performed integrative analysis of phosphoproteomics, bioinformatics, and cell proliferation assays on a panel of 12 molecularly heterogeneous CRC cell lines. Using the high-resolute data-independent analysis mass spectrometry (DIA-MS), we monitored a total of 10,142 proteins and 56,080 phosphosites (P-sites) in CRC cells upon a short- and a long-term metformin treatment.

RESULTS AND CONCLUSIONS

We found that metformin tended to primarily remodel cell signaling in the long-term and only minimally regulated the total proteome expression levels. Strikingly, the phosphorylation signaling response to metformin was highly heterogeneous in the CRC panel, based on a network analysis inferring kinase/phosphatase activities and cell signaling reconstruction. A "MetScore" was determined to assign the metformin relevance of each P-site, revealing new and robust phosphorylation nodes and pathways in metformin signaling. Finally, we leveraged the metformin P-site signature to identify pharmacodynamic interactions and confirmed a number of candidate metformin-interacting drugs, including navitoclax, a BCL-2/BCL-xL inhibitor. Together, we provide a comprehensive phosphoproteomic resource to explore the metformin-induced cell signaling for potential cancer therapeutics. This resource can be accessed at https://yslproteomics.shinyapps.io/Metformin/.

Evaluating the safety and efficacy of the leukotriene receptor antagonist montelukast as adjuvant therapy in obese patients with type 2 diabetes mellitus: A double-blind, randomized, placebo-controlled trial

Background: Type 2 diabetes mellitus (T2DM) is common with obesity. Metformin is a first-line therapy for this condition. However, it has only a minor impact on weight loss in some patients. Aim: This study aimed to evaluate the effectiveness, tolerability, and safety of combining montelukast therapy with metformin in obese diabetic patients. Methods: One hundred obese diabetic adult patients were recruited and randomized into two equal groups. Group 1 received placebo plus metformin 2 g/d, and Group 2 received 2 g/d metformin plus 10 mg/d montelukast. Demographic, anthropometric measurements (e.g., body weight, body mass index [BMI], and visceral adiposity index), lipid profile, diabetes control measures (fasting blood glucose, glycated hemoglobin [HbA1c], and homeostatic model assessment for insulin resistance [HOMA-IR]), adiponectin, and inflammatory markers (e.g., TNF-α, IL-6, and leukotriene B4) were assessed and reported for each group at baseline and after 12 weeks of treatment. Results: Both interventions significantly reduced all the measured parameters, except for adiponectin and HDL-C, levels of which increased compared to baseline data (p < 0.001). The montelukast group significantly improved in all parameters compared to the placebo group (ANCOVA test p < 0.001). The percentage changes in BMI, HbA1c, HOMA-IR, and inflammatory markers were 5%, 9%, 41%, and 5%-30%, respectively, in the placebo group compared to 8%, 16%, 58%, and 50%-70%, respectively, in the montelukast group. Conclusion: Montelukast adjuvant therapy was superior to metformin-only therapy in diabetes control and weight loss, most likely due to its increased insulin sensitivity and anti-inflammatory properties. The combination was tolerable and safe throughout the study duration. Clinical Trial Registration: [Clinicaltrial.gov], identifier [NCT04075110].

Reassessing the evidence of a survival advantage in Type 2 diabetes treated with metformin compared with controls without diabetes: a retrospective cohort study

BACKGROUND

Previous research has suggested that individuals with Type 2 diabetes and initiated on metformin monotherapy present with a survival advantage compared with the general population without diabetes. This finding has generated considerable interest in the prophylactic use of metformin against age-related morbidity.

METHODS

Utilizing Danish National Health Registers, we assessed differences in survival associated with metformin monotherapy for Type 2 diabetes compared with no diagnosis of diabetes in both singleton and discordant twin populations between 1996 and 2012. Data were analysed in both nested case-control and matched cohort study designs, with incidence rate ratios (IRRs) and hazard ratios estimated using conditional logistic regression and Cox proportional hazards regression, respectively.

RESULTS

In case-control pairs matched on birth year and sex or co-twin (sex, birth year and familial factors), incident Type 2 diabetes with treatment by metformin monotherapy initiation compared with no diagnosis of diabetes was associated with increased mortality in both singletons (IRR = 1.52, 95% CI: 1.37, 1.68) and discordant twin pairs (IRR = 1.90, 95% CI: 1.35, 2.67). After adjusting for co-morbidities and social indicators, these associations were attenuated to 1.32 (95% CI: 1.16, 1.50) and 1.64 (95% CI: 1.10, 2.46), respectively. Increased mortality was observed across all levels of cumulative use and invariant to a range of study designs and sensitivity analyses.

CONCLUSIONS

Treatment initiation by metformin monotherapy in Type 2 diabetes was not associated with survival equal or superior to that of the general population without diabetes. Our contrasting findings compared with previous research are unlikely to be the result of differences in epidemiological or methodological parameters.

Metformin Acutely Mitigates Oxidative Stress in Human Atrial Tissue: A Pilot Study in Overweight Non-Diabetic Cardiac Patients

Metformin, the first-line drug in type 2 diabetes mellitus, elicits cardiovascular protection also in obese patients via pleiotropic effects, among which the anti-oxidant is one of the most investigated. The aim of the present study was to assess whether metformin can acutely mitigate oxidative stress in atrial tissue harvested from overweight non-diabetic patients. Right atrial appendage samples were harvested during open-heart surgery and used for the evaluation of reactive oxygen species (ROS) production by means of confocal microscopy (superoxide anion) and spectrophotometry (hydrogen peroxide). Experiments were performed after acute incubation with metformin (10 µM) in the presence vs. absence of angiotensin II (AII, 100 nM), lipopolysaccharide (LPS, 1 μg/mL), and high glucose (Gluc, 400 mg/dL). Stimulation with AII, LPS, and high Gluc increased ROS production. The magnitude of oxidative stress correlated with several echocardiographic parameters. Metformin applied in the lowest therapeutic concentration (10 µM) was able to decrease ROS generation in stimulated but also non-stimulated atrial samples. In conclusion, in a pilot group of overweight non-diabetic cardiac patients, acute incubation with metformin at a clinically relevant dose alleviated oxidative stress both in basal conditions and conditions that mimicked the activation of the renin-angiotensin-aldosterone system, acute inflammation, and uncontrolled hyperglycemia.

The Effectiveness and Safety of Metformin Compared to Sulfonylureas in Diabetic Nephropathy: A Systematic Review

Metformin and sulphonylureas are the most commonly used first-line anti-diabetic agents. However, medical practice guidelines and clinical experience caution against using these drugs in severe diabetic kidney disease. Consequently, the choice of anti-diabetic medicine in various stages of diabetic nephropathy should balance the benefits and risks to the patient. We aim to synthesize available evidence on the effectiveness and safety of metformin concerning sulfonylureas in patients with diabetic renal disease. The COSMOS-E (Guidance on conducting systematic reviews and meta-analyses of observational studies of etiology) and MOOSE (Meta-Analyses and Systematic Reviews of Observational Studies in Epidemiology) guidelines were followed when designing the systematic review. The present study assessed the effectiveness of metformin and sulphonylurea monotherapy regarding renal function. Studies published from 2001 to 2022 were included. We have identified 570 records from PubMed, BioMed Central, LILACS (Literatura Latino-Americana e do Caribe em Ciências da Saúde), ScienceDirect, and PLoS (The Public Library of Science) Medicine databases. Eight cohort studies met the inclusion criteria. All studies reported adjusted hazard ratios with confidence limits. Metformin was found to be more effective in the following events: all-cause mortality, GFR (glomerular filtration rate), ESRD (end-stage renal disease) or death events, one-year risk of death or end-stage renal disease, cardiovascular events, heart failure hospitalization, and hypoglycemic episodes. However, metformin was less effective in acute renal replacement therapy, end-stage renal disease, and/or death, with a one-year risk of acute dialysis. Lactic acidosis was not significant with metformin. The present study recommends that metformin therapy is safe compared to sulfonylurea therapy in diabetic nephropathy patients, provided that the contraindications given in the guidelines are strictly adhered to.

Scrophulariae Radix-Atractylodes sinensis pair and metformin inhibit inflammation by modulating gut microbiota of high-fat diet/streptozotocin-induced diabetes in rats

INTRODUCTION

Type 2 mellitus (T2DM), a chronic metabolic disorder, causes severe impairment of patients' quality of life and has attracted global attention. Many studies have suggested the importance of the gut microbiota in the occurrence of T2DM. The Scrophulariae Radix and Atractylodes sinensis (XC) pair, recommended in traditional Chinese medicine (TCM), have been used for treating diabetes for many years. However, research on the role of the XC pair in modulating gut microbial communities is lacking, but it is important to elucidate the underlying mechanism.

METHODS

In this study, we detected bacterial communities by high-throughput 16S rRNA gene sequencing.

RESULTS

The results showed that XC + MET reduced postprandial hyperglycemia and inflammatory response in diabetic rats more effectively than metformin (MET) alone. The XC + MET treatment reshaped the intestinal microbial composition of diabetic rats. XC can help MET regulate carbohydrate, amino acid, and lipid metabolism, particularly the insulin signaling pathway.

DISCUSSION

This research would help elucidate potential mechanisms and the treatment methods.

From Diabetes to Atherosclerosis: Potential of Metformin for Management of Cardiovascular Disease

Atherosclerosis is a common cause of cardiovascular disease, which, in turn, is often fatal. Today, we know a lot about the pathogenesis of atherosclerosis. However, the main knowledge is that the disease is extremely complicated. The development of atherosclerosis is associated with more than one molecular mechanism, each making a significant contribution. These mechanisms include endothelial dysfunction, inflammation, mitochondrial dysfunction, oxidative stress, and lipid metabolism disorders. This complexity inevitably leads to difficulties in treatment and prevention. One of the possible therapeutic options for atherosclerosis and its consequences may be metformin, which has already proven itself in the treatment of diabetes. Both diabetes and atherosclerosis are complex metabolic diseases, the pathogenesis of which involves many different mechanisms, including those common to both diseases. This makes metformin a suitable candidate for investigating its efficacy in cardiovascular disease. In this review, we highlight aspects such as the mechanisms of action and targets of metformin, in addition to summarizing the available data from clinical trials on the effective reduction of cardiovascular risks.

Metformin inhibits melanoma cell metastasis by suppressing the miR-5100/SPINK5/STAT3 axis

Melanoma is the most lethal skin cancer characterized by its high metastatic potential. It is urgent to find novel therapy strategies to overcome this feature. Metformin has been confirmed to suppress invasion and migration of various types of cancer. However, additional mechanisms underlying the antimetastatic effect of metformin on melanoma require further investigation. Here, we performed microarray analysis and uncovered an altered mRNA and miRNA expression profile between melanoma and nevus. Luciferase reporter assay confirmed that miR-5100 targets SPINK5 to activate STAT3 phosphorylation. Migration and wound healing assays showed that the miR-5100/SPINK5/STAT3 axis promotes melanoma cell metastasis; the mechanism was proven by initiation of epithelial–mesenchymal transition. Co-immunoprecipitation (Co-IP) further confirmed an indirect interaction between SPINK5 and STAT3. Furthermore, metformin dramatically inhibited miR-5100/SPINK5/STAT3 pathway, and decreased B16-F10 cell metastasis to lung in C57 mouse module. Intriguingly, pretreatment of metformin before melanoma cell injection improved this effect further. These findings exposed the underlying mechanisms of action of metformin and update the use of this drug to prevent metastasis in melanoma.

Can metformin relieve tibiofemoral cartilage volume loss and knee symptoms in overweight knee osteoarthritis patients? Study protocol for a randomized, double-blind, and placebo-controlled trial

Background

Osteoarthritis (OA) is the most common joint disease, and is most frequently seen in the knees. However, there is no effective therapy to relieve the progression of knee OA. Metformin is a safe, well-tolerated oral medication that is extensively used as first-line therapy for type 2 diabetes. Previous observational studies and basic researches suggested that metformin may have protective effects on knee OA, which needs to be verified by clinical trials. This study, therefore, aims to examine the effects of metformin versus placebo on knee cartilage volume loss and knee symptoms in overweight knee OA patients by a randomized controlled trial over 24 months.

Methods

This protocol describes a multicenter, randomized, double-blind, and placebo-controlled clinical trial aiming to recruit 262 overweight knee OA patients. Participants will be randomly allocated to the two arms of the study, receiving metformin hydrochloride sustained-release tablets or identical inert placebo for 24 months (start from 0.5 g/day for the first 2 weeks, and increase to 1 g/day for the second 2 weeks, and further increase to 2 g/day for the remaining period if tolerated). Primary outcomes will be changes in tibiofemoral cartilage volume and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score over 24 months. Secondary outcomes will be changes in visual analogue scale (VAS) knee pain, tibiofemoral cartilage defects, effusion-synovitis volume, and tibiofemoral bone marrow lesions maximum size over 24 months. The primary analyses will be intention-to-treat analyses of primary and secondary outcomes. Per-protocol analyses will be performed as the secondary analyses.

Discussion

If metformin is proved to slow knee cartilage volume loss and to relieve knee symptoms among overweight knee OA patients, it will have the potential to become a disease modifying drug for knee OA. Metformin is a convenient intervention with low cost, and its potential effects on slowing down the structural progression and relieving the symptoms of knee OA would effectively reduce the disease burden worldwide.

Trial registration

ClinicalTrials. gov NCT05034029. Registered on 30 Sept 2021.

A precision medicine approach to metabolic therapy for breast cancer in mice

Increasing evidence highlights approaches targeting metabolism as potential adjuvants to cancer therapy. Sodium-glucose transport protein 2 (SGLT2) inhibitors are the newest class of antihyperglycemic drugs. To our knowledge, SGLT2 inhibitors have not been applied in the neoadjuvant setting as a precision medicine approach for this devastating disease. Here, we treat lean breast tumor-bearing mice with the SGLT2 inhibitor dapagliflozin as monotherapy and in combination with paclitaxel chemotherapy. We show that dapagliflozin enhances the efficacy of paclitaxel, reducing tumor glucose uptake and prolonging survival. Further, the ability of dapagliflozin to enhance the efficacy of chemotherapy correlates with its effect to reduce circulating insulin in some but not all breast tumors. Our data suggest a genetic signature for breast tumors more likely to respond to dapagliflozin in combination with paclitaxel. In the current study, tumors driven by mutations upstream of canonical insulin signaling pathways responded to this combined treatment, whereas tumors driven by mutations downstream of canonical insulin signaling did not. These data demonstrate that dapagliflozin enhances the response to chemotherapy in mice with breast cancer and suggest that patients with driver mutations upstream of canonical insulin signaling may be most likely to benefit from this neoadjuvant approach.

Inflammatory Mechanisms of Diabetes and Its Vascular Complications

The main cause of death in patients with type 2 DM is cardiovascular complications resulting from the progression of atherosclerosis. The pathophysiology of the association between diabetes and its vascular complications is complex and multifactorial and closely related to the toxic effects of hyperglycemia that causes increased generation of reactive oxygen species and promotes the secretion of pro-inflammatory cytokines. Subsequent oxidative stress and inflammation are major factors of the progression of type 2 DM and its vascular complications. Data on the pathogenesis of the development of type 2 DM and associated cardiovascular diseases, in particular atherosclerosis, open up broad prospects for the further development of new diagnostic and therapeutic approaches.

Metformin in nucleus accumbens core reduces cue-induced cocaine seeking in male and female rats

This study investigated the potential therapeutic effects of the FDA‐approved drug metformin on cue‐induced reinstatement of cocaine seeking. Metformin (dimethyl‐biguanide) is a first‐line treatment for type II diabetes that, among other mechanisms, is involved in the activation of adenosine monophosphate activated protein kinase (AMPK). Cocaine self‐administration and extinction is associated with decreased levels of phosphorylated AMPK within the nucleus accumbens core (NAcore). Previously, it was shown that increasing AMPK activity in the NAcore decreased cue‐induced reinstatement of cocaine seeking. Decreasing AMPK activity produced the opposite effect. The goal of the present study was to determine if metformin in the NAcore reduces cue‐induced cocaine seeking in adult male and female Sprague Dawley rats. Rats were trained to self‐administer cocaine followed by extinction prior to cue‐induced reinstatement trials. Metformin microinjected in the NAcore attenuated cue‐induced reinstatement in male and female rats. Importantly, metformin's effects on cocaine seeking were not due to a general depression of spontaneous locomotor activity. In female rats, metformin's effects did generalize to a reduction in cue‐induced reinstatement of sucrose seeking. These data support a potential role for metformin as a pharmacotherapy for cocaine use disorder but warrant caution given the potential for metformin's effects to generalize to a natural reward in female rats.

Eating out of Home: Influence on Nutrition, Health, and Policies: A Scoping Review

Eating out of home (EOH) is a common practice worldwide but research gaps have been identified. The aims of this review were (a) to find a common definition for EOH, (b) to determine the nutritional contribution of EOH, and (c) to analyze the relationship of EOH with health parameters in adults. Fifty-seven articles were finally selected. The definition of EOH was not harmonized between researchers and the comparison between studies was quite difficult. Restaurant and fast food were the terms most used, followed by chain restaurant, à la carte, sit-down restaurant, eating at table, full service, ready to eat, takeaway, buffet and buffet by weight, bar, cafes, and cafeterias, either alone or attached to at least one of the above. The profile of the main EOH participant was a highly educated, high-income, and unmarried young man. EOH was related to a body mass index (BMI) or being overweight in a different way depending on age, sex, or EOH frequency. A high rate of EOH led to poorer diet quality, characterized by higher intakes of energy, total and saturated fats, sugar, and sodium, as well as lower intakes of fiber, dairy, fruit, vegetables, and micronutrients. Regarding beverages, a higher intake of soft drinks, sugar-sweetened beverages, fruit juices, beer, and other alcohol was observed when EOH. There is a need for a methodological consensus for analyzing the impact of EOH on dietary intake and health to avoid bias. Additionally, measures and policies should be utilized to help consumers to make healthier choices when EOH is compatible with business regarding those running EOH establishments.

Metformin Intervention—A Panacea for Cancer Treatment?

The molecular mechanism of action and the individual influence of various metabolic pathways related to metformin intervention are under current investigation. The available data suggest that metformin provides many advantages, exhibiting anti-inflammatory, anti-cancer, hepatoprotective, cardioprotective, otoprotective, radioprotective, and radio-sensitizing properties depending on cellular context. This literature review was undertaken to provide novel evidence concerning metformin intervention, with a particular emphasis on cancer treatment and prevention. Undoubtedly, the pleiotropic actions associated with metformin include inhibiting inflammatory processes, increasing antioxidant capacity, and improving glycemic and lipid metabolism. Consequently, these characteristics make metformin an attractive medicament to translate to human trials, the promising results of which were also summarized in this review.

Synergistic In Vitro Antimicrobial Activity of Triton X-100 and Metformin against Enterococcus faecalis in Normal and High-Glucose Conditions

The prevention and treatment of oral diseases is more difficult in diabetic patients with poorly controlled blood glucose levels. This study aims to explore an effective, low-cytotoxicity medication for root canal treatment in diabetic patients. The antibacterial effect of the combination of Triton X-100 (TX-100) and metformin (Met) on Enterococcus faecalis (E. faecalis) was evaluated by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration required to kill 99% bacteria (MBC₉₉) and by conducting dynamic time-killing assays. While the antibiofilm activity was measured by crystal violet (CV) assay, field emission scanning electron microscope (FE-SEM), confocal laser scanning microscope (CLSM) and colony-forming unit (CFU) counting assays. The expression of relative genes was evaluated by real-time quantitative polymerase chain reaction (RT-qPCR), and the cytotoxicity of the new combination on MC3T3-E1 cell was also tested. Results showed that the antibacterial and antibiofilm activities of Met could be significantly enhanced by very low concentrations of TX-100 in both normal and high-glucose conditions, with a much lower cytotoxicity than 2% chlorhexidine (CHX). Thus, the TX-100 + Met combination may be developed as a promising and effective root canal disinfectant for patients with diabetes.

The Effects of Separate and Combined Treatment of Male Rats with Type 2 Diabetes with Metformin and Orthosteric and Allosteric Agonists of Luteinizing Hormone Receptor on Steroidogenesis and Spermatogenesis

In men with type 2 diabetes mellitus (T2DM), steroidogenesis and spermatogenesis are impaired. Metformin and the agonists of luteinizing hormone/human chorionic gonadotropin(hCG)-receptor (LH/hCG-R) (hCG, low-molecular-weight allosteric LH/hCG-R-agonists) can be used to restore them. The aim was to study effectiveness of separate and combined administration of metformin, hCG and 5-amino-N-tert-butyl-2-(methylsulfanyl)-4-(3-(nicotinamido)phenyl)thieno[2,3-d]pyrimidine-6-carboxamide (TP3) on steroidogenesis and spermatogenesis in male rats with T2DM. hCG (15 IU/rat/day) and TP3 (15 mg/kg/day) were injected in the last five days of five-week metformin treatment (120 mg/kg/day). Metformin improved testicular steroidogenesis and spermatogenesis and restored LH/hCG-R-expression. Compared to control, in T2DM, hCG stimulated steroidogenesis and StAR-gene expression less effectively and, after five-day administration, reduced LH/hCG-R-expression, while TP3 effects changed weaker. In co-administration of metformin and LH/hCG-R-agonists, on the first day, stimulating effects of LH/hCG-R-agonists on testosterone levels and hCG-stimulated expression of StAR- and CYP17A1-genes were increased, but on the 3-5th day, they disappeared. This was due to reduced LH/hCG-R-gene expression and increased aromatase-catalyzed estradiol production. With co-administration, LH/hCG-R-agonists did not contribute to improving spermatogenesis, induced by metformin. Thus, in T2DM, metformin and LH/hCG-R-agonists restore steroidogenesis and spermatogenesis, with metformin being more effective in restoring spermatogenesis, and their co-administration improves LH/hCG-R-agonist-stimulating testicular steroidogenesis in acute but not chronic administration.

Clinical Targeting of Altered Metabolism in High-Grade Glioma

ABSTRACT

High-grade gliomas are among the deadliest of all cancers despite standard treatments, and new therapeutic strategies are needed to improve patient outcome. Targeting the altered metabolic state of tumors with traditional chemotherapeutic agents has a history of success, and our increased understanding of cellular metabolism in the past 2 decades has reinvigorated the concept of novel metabolic therapies in brain tumors. Here we highlight metabolic alterations in advanced gliomas and their translation into clinical trials using both novel agents and already established drugs repurposed for cancer treatment in an effort to improve outcome for these deadly diseases.

Metformin Transport Rates Between Plasma and Red Blood Cells in Humans

Background

Metformin has been used for the treatment of type 2 diabetes for over 60 years; however, its mechanism of pharmacological action is not fully clear. Different hypotheses exist regarding metformin distribution and redistribution mechanisms between plasma and erythrocytes/red blood cells (RBCs).

Objective

We aimed to test the hypothesis that the metformin distribution between plasma and RBC occurs via concentration difference-driven passive transport and estimated transport rate coefficient values based on metformin concentration time series in plasma and RBCs from in vivo studies.

Methods

An ordinary differential equation (ODE) system with two compartments was used to describe diffusion-based passive transport between plasma and RBCs. Metformin concentration time series in plasma and RBCs of 35 individuals were used for metformin transport parametrization. Plasma concentration has been approximated by biexponential decline.

Results

A single passive transport coefficient, k = 0.044 ± 0.014 (h^–1), can be applied, describing the uptake and release transport rate versus the linear equation v = k × (M_pl − M_RBC), where M_pl is the metformin concentration in plasma and M_RBC is the metformin concentration in RBCs.

Conclusions

Our research suggests that passive transport can explain metformin distribution dynamics between plasma and RBCs because transport speed is proportional to the metformin concentration difference and independent of the transport direction. Concentration difference-driven passive transport can explain the mechanism of faster metformin distribution to RBCs the first few hours after administration, and faster release and domination of the redistribution transport rate after metformin concentration in plasma becomes smaller than in RBCs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-021-01058-2.

Metformin Affects Cardiac Arachidonic Acid Metabolism and Cardiac Lipid Metabolite Storage in a Prediabetic Rat Model

Metformin can reduce cardiovascular risk independent of glycemic control. The mechanisms behind its non-glycemic benefits, which include decreased energy intake, lower blood pressure and improved lipid and fatty acid metabolism, are not fully understood. In our study, metformin treatment reduced myocardial accumulation of neutral lipids—triglycerides, cholesteryl esters and the lipotoxic intermediates—diacylglycerols and lysophosphatidylcholines in a prediabetic rat model (p < 0.001). We observed an association between decreased gene expression and SCD-1 activity (p < 0.05). In addition, metformin markedly improved phospholipid fatty acid composition in the myocardium, represented by decreased SFA profiles and increased n3-PUFA profiles. Known for its cardioprotective and anti-inflammatory properties, metformin also had positive effects on arachidonic acid metabolism and CYP-derived arachidonic acid metabolites. We also found an association between increased gene expression of the cardiac isoform CYP2c with increased 14,15-EET (p < 0.05) and markedly reduced 20-HETE (p < 0.001) in the myocardium. Based on these results, we conclude that metformin treatment reduces the lipogenic enzyme SCD-1 and the accumulation of the lipotoxic intermediates diacylglycerols and lysophosphatidylcholine. Increased CYP2c gene expression and beneficial effects on CYP-derived arachidonic acid metabolites in the myocardium can also be involved in cardioprotective effect of metformin.

Sustained In Vitro and In Vivo Delivery of Metformin from Plant Pollen-Derived Composite Microcapsules

We developed a dual microencapsulation platform for the type 2 diabetes drug metformin (MTF), which is aimed to increase its bioavailability. We report the use of Lycopodium clavatum sporopollenin (LCS), derived from their natural spores, and raw Phoenix dactylifera L. (date palm) pollens (DPP) for MTF microencapsulation. MTF was loaded into LCS and DPP via a vacuum and a novel method of hydration-induced swelling. The loading capacity (LC) and encapsulation efficiency (EE) percentages for MTF-loaded LCS and MTF-loaded DPP microcapsules were 14.9% ± 0.7, 29.8 ± 0.8, and 15.2% ± 0.7, 30.3 ± 1.0, respectively. The release of MTF from MTF-loaded LCS microcapsules was additionally controlled by re-encapsulating the loaded microcapsules into calcium alginate (ALG) microbeads via ionotropic gelation, where the release of MTF was found to be significantly slower and pH-dependent. The pharmacokinetic parameters, obtained from the in vivo study, revealed that the relative bioavailability of the MTF-loaded LCS-ALG beads was 1.215 times higher compared to pure MTF, following oral administration of a single dose equivalent to 25 mg/kg body weight MTF to streptozotocin (STZ)-induced diabetic male Sprague-Dawley rats. Significant hypoglycemic effect was obtained for STZ-induced diabetic rats orally treated with MTF-loaded LCS-ALG beads compared to control diabetic rats. Over a period of 29 days, the STZ-induced diabetic rats treated with MTF-loaded LCS-ALG beads showed a decrease in the aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglycerides, cholesterol, and low-density lipoprotein-cholesterol (LDL-C) levels, as well as an increase in glutathione peroxidase (GPx) and a recovery in the oxidative stress biomarker, lipid peroxidation (LPx). In addition, histopathological studies of liver, pancreas, kidney, and testes suggested that MTF-loaded LCS-ALG beads improved the degenerative changes in organs of diabetic rats. The LCS-ALG platform for dual encapsulation of MTF achieved sustained MTF delivery and enhancement of bioavailability, as well as the improved biochemical and histopathological characteristics in in vivo studies, opening many other intriguing applications in sustained drug delivery.