Metformin selectively dampens the acute inflammatory response through an AMPK-dependent mechanism

Metformin as a Therapeutic Agent for Obesity-Associated Immune Dysfunction

Obesity is associated with impaired immune function, characterized by inflammation, and leading to poor response to infection, impaired vaccine response, increased susceptibility to autoimmune disease, and increased risk of cancer and cancer mortality. Worse, there is evidence that weight loss alone may be insufficient to reverse the immune dysfunction caused by obesity. It is therefore critically important to identify alternative therapeutic approaches to decrease the negative effects of obesity-associated inflammation. In this article, we will review evidence that the antidiabetic drug metformin may be considered as a therapeutic agent for obesity-associated immune dysfunction. Metformin has immunomodulatory effects, stimulating or suppressing the immune response in both a cell-specific and disease-specific manner. Although the mechanism of action of metformin on the immune system remains to be fully elucidated, there is strong evidence that metformin enters select immune cells and disrupts electron transport, leading to both AMP-activated protein kinase (AMPK)-dependent and AMPK-independent effects on immune cell differentiation and cytokine production. These effects of metformin on immune cells have been shown to improve immune responses to infection, autoimmunity, and cancer.

Deciphering the shared mechanisms of Gegen Qinlian Decoction in treating type 2 diabetes and ulcerative colitis via bioinformatics and machine learning

Background

Although previous clinical studies and animal experiments have demonstrated the efficacy of Gegen Qinlian Decoction (GQD) in treating Type 2 Diabetes Mellitus (T2DM) and Ulcerative Colitis (UC), the underlying mechanisms of its therapeutic effects remain elusive.

Purpose

This study aims to investigate the shared pathogenic mechanisms between T2DM and UC and elucidate the mechanisms through which GQD modulates these diseases using bioinformatics approaches.

Methods

Data for this study were sourced from the Gene Expression Omnibus (GEO) database. Targets of GQD were identified using PharmMapper and SwissTargetPrediction, while targets associated with T2DM and UC were compiled from the DrugBank, GeneCards, Therapeutic Target Database (TTD), DisGeNET databases, and differentially expressed genes (DEGs). Our analysis encompassed six approaches: weighted gene co-expression network analysis (WGCNA), immune infiltration analysis, single-cell sequencing analysis, machine learning, DEG analysis, and network pharmacology.

Results

Through GO and KEGG analysis of weighted gene co-expression network analysis (WGCNA) modular genes and DEGs intersection, we found that the co-morbidity between T2DM and UC is primarily associated with immune-inflammatory pathways, including IL-17, TNF, chemokine, and toll-like receptor signaling pathways. Immune infiltration analysis supported these findings. Three distinct machine learning studies identified IGFBP3 as a biomarker for GQD in treating T2DM, while BACE2, EPHB4, and EPHA2 emerged as biomarkers for GQD in UC treatment. Network pharmacology revealed that GQD treatment for T2DM and UC mainly targets immune-inflammatory pathways like Toll-like receptor, IL-17, TNF, MAPK, and PI3K-Akt signaling pathways.

Conclusion

This study provides insights into the shared pathogenesis of T2DM and UC and clarifies the regulatory mechanisms of GQD on these conditions. It also proposes novel targets and therapeutic strategies for individuals suffering from T2DM and UC.

Impact of Antidiabetic Drugs on Clinical Outcomes of COVID-19: A Nationwide Population-Based Study

BACKGRUOUND

Inconsistent results have been reported regarding the association between the use of antidiabetic drugs and the clinical outcomes of coronavirus disease 2019 (COVID-19). This study aimed to investigate the effect of antidiabetic drugs on COVID-19 outcomes in patients with diabetes using data from the National Health Insurance Service (NHIS) in South Korea.

METHODS

We analyzed the NHIS data of patients aged ≥20 years who tested positive for COVID-19 and were taking antidiabetic drugs between December 2019 and June 2020. Multiple logistic regression analysis was performed to analyze the clinical outcomes of COVID-19 based on the use of antidiabetic drugs.

RESULTS

A total of 556 patients taking antidiabetic drugs tested positive for COVID-19, including 271 male (48.7%), most of whom were in their sixties. Of all patients, 433 (77.9%) were hospitalized, 119 (21.4%) received oxygen treatment, 87 (15.6%) were admitted to the intensive care unit, 31 (5.6%) required mechanical ventilation, and 61 (11.0%) died. Metformin was significantly associated with the lower risks of mechanical ventilation (odds ratio [OR], 0.281; 95% confidence interval [CI], 0.109 to 0.720; P=0.008), and death (OR, 0.395; 95% CI, 0.182 to 0.854; P=0.018). Dipeptidylpeptidase-4 inhibitor (DPP-4i) were significantly associated with the lower risks of oxygen treatment (OR, 0.565; 95% CI, 0.356 to 0.895; P=0.015) and death (OR, 0.454; 95% CI, 0.217 to 0.949; P=0.036). Sulfonylurea was significantly associated with the higher risk of mechanical ventilation (OR, 2.579; 95% CI, 1.004 to 6.626; P=0.049).

CONCLUSION

In patients with diabetes and COVID-19, metformin exhibited reduced risks of mechanical ventilation and death, DPP- 4i was linked with lower risks of oxygen treatment and death, while sulfonylurea was related to the increased risk of mechanical ventilation.

Effects of different treatments for type 2 diabetes mellitus on mortality of coronavirus disease from 2019 to 2021 in China: a multi-institutional retrospective study

The coronavirus disease (COVID-19) pandemic has continued for 5 years. Sporadic cases continue to occur in different locations. Type 2 diabetes mellitus (T2DM) is associated with a high risk of a poor prognosis in patients with COVID-19. Successful control of blood glucose levels can effectively decrease the risks of severe infections and mortality. However, the effects of different treatments were reported differently and even adversely. This retrospective study included 4,922 patients who have been diagnosed as COVID-19 and T2DM from 138 Hubei hospitals. The clinical characteristics and outcomes were compared and calculated their risk for death using multivariate Cox regression and Kaplan-Meier curves. After adjustment of age, sex, comorbidities, and in-hospital medications, metformin and alpha-glucosidase inhibitor (AGI) use performed lower all-cause mortality (adjusted hazard ratio [HR], 0.41; 95% confidence interval [CI]: 0.24-0.71; p = 0.001 for metformin; 0.53, 0.35-0.80, p = 0.002 for AGIs), while insulin use was associated with increased all-cause mortality (adjusted HR, 2.07, 95% CI, 1.61-2.67, p < 0.001). After propensity score-matched (PSM) analysis, adjusted HRs for insulin, metformin, and AGIs associated with all-cause mortality were 1.32 (95% CI, 1.03-1.81; p = 0.012), 0.48 (95% CI, 0.23-0.83, p = 0.014), and 0.59 (95% CI, 0.35-0.98, p = 0.05). Therefore, metformin and AGIs might be more suitable for patients with COVID-19 and T2DM while insulin might be used with caution.

Anexelekto (AXL) no more: microRNA-155 (miR-155) controls the "Uncontrolled" in SARS-CoV-2

AXL is the gene that encodes the Anexelekto (AXL) receptor tyrosine kinase that demonstrates significant roles in various cellular processes, including cell growth, survival, and migration. Anexelekto is a Greek word meaning excessive and uncontrolled, semantically implying the crucial involvement of AXL in cancer and immune biology, and in promoting cancer metastasis. AXL overexpression appears to drive epithelial to mesenchymal transition, tumor angiogenesis, decreased antitumor immune response, and resistance to therapeutic agents. Recently, AXL has been reported to play important roles in several viral infections, including SARS-CoV-2. We have previously outlined the importance of microRNAs (miRNAs, miRs) and especially miR-155 in SARS-CoV-2 pathophysiology through regulation of the Renin-Angiotensin Aldosterone System (RAAS) and influence on several aspects of host innate immunity. MiRNAs are negative regulators of gene expression, decreasing the stability of target RNAs or limiting their translation and, enthrallingly, miR-155 is also involved in AXL homeostasis-both endogenously and pharmaceutically using repurposed drugs (e.g., metformin)-highlighting thrifty evolutionary host innate immunity mechanisms that successfully can thwart viral entry and replication. Cancer, infections, and immune system disturbances will increasingly involve miRNA diagnostics and therapeutics in the future.

Is Metformin Use Associated with a More Favorable COVID-19 Course in People with Diabetes?

Background: Diabetes Mellitus (DM) has been associated with a higher Coronavirus disease-19 (COVID-19) mortality, both in hospitalized patients and in the general population. A possible beneficial effect of metformin on the prognosis of COVID-19 has been reported in some observational studies, whereas other studies disagree. Methods: To investigate the possible effect of metformin on COVID-19 in-hospital mortality, we performed a retrospective study that included all SARS-CoV-2-positive patients with DM who were admitted to two Italian hospitals. In order to adjust for possible confounders accounting for the observed reduction of mortality in metformin users, we adopted the COVID-19 Mortality Risk Score (COVID-19 MRS) as a covariate. Results: Out of the 524 included patients, 33.4% died. A binomial logistic regression showed that metformin use was associated with a significant reduction in case fatality (OR 0.67 [0.45-0.98], p = 0.039), with no significant effect on the need for ventilation (OR 0.75 [0.5-1.11], p = 0.146). After adjusting for COVID-19 MRS, metformin did not retain a significant association with in-hospital mortality [OR 0.795 (0.495-1.277), p = 0.342]. Conclusions: A beneficial effect of metformin on COVID-19 was not proven after adjusting for confounding factors. The use of validated tools to stratify the risk for COVID-19 severe disease and death, such as COVID-19 MRS, may be useful to better explore the potential association of medications and comorbidities with COVID-19 prognosis.

Dysregulation of the mRNA Expression of Human Renal Drug Transporters by Proinflammatory Cytokines in Primary Human Proximal Tubular Epithelial Cells

Proinflammatory cytokines, which are elevated during inflammation or infections, can affect drug pharmacokinetics (PK) due to the altered expression or activity of drug transporters and/or metabolizing enzymes. To date, such studies have focused on the effect of cytokines on the activity and/or mRNA expression of hepatic transporters and drug-metabolizing enzymes. However, many antibiotics and antivirals used to treat infections are cleared by renal transporters, including the basal organic cation transporter 2 (OCT2), organic anion transporters 1 and 3 (OAT1 and 3), the apical multidrug and toxin extrusion proteins 1 and 2-K (MATE1/2-K), and multidrug resistance-associated protein 2 and 4 (MRP2/4). Here, we determined the concentration-dependent effect of interleukin-6 (IL-6), IL-1β, tumor necrosis factor (TNF)-α, and interferon-γ (IFN-γ) on the mRNA expression of human renal transporters in freshly isolated primary human renal proximal tubular epithelial cells (PTECs, n = 3-5). PTECs were exposed to either a cocktail of cytokines, each at 0.01, 0.1, 1, or 10 ng/mL or individually at the same concentrations. Exposure to the cytokine cocktail for 48 h was found to significantly downregulate the mRNA expression, in a concentration-dependent manner, of OCT2, the organic anion transporting polypeptides 4C1 (OATP4C1), OAT4, MATE2-K, P-glycoprotein (P-gp), and MRP2 and upregulate the mRNA expression of the organic cation/carnitine transporter 1 (OCTN1) and MRP3. OAT1 and OAT3 also appeared to be significantly downregulated but only at 0.1 and 10 ng/mL, respectively, without a clear concentration-dependent trend. Among the cytokines, IL-1β appeared to be the most potent at down- and upregulating the mRNA expression of the transporters. Taken together, our results demonstrate for the first time that proinflammatory cytokines transcriptionally dysregulate renal drug transporters in PTECs. Such dysregulation could potentially translate into changes in transporter protein abundance or activity and alter renal transporter-mediated drug PK during inflammation or infections.

Insulin feedback is a targetable resistance mechanism of PI3K inhibition in glioblastoma

BACKGROUND

Insulin feedback is a critical mechanism responsible for the poor clinical efficacy of phosphatidylinositol 3-kinase (PI3K) inhibition in cancer, and hyperglycemia is an independent factor associated with poor prognosis in glioblastoma (GBM). We investigated combination anti-hyperglycemic therapy in a mouse model of GBM and evaluated the association of glycemic control in clinical trial data from patients with GBM.

METHODS

The effect of the anti-hyperglycemic regimens, metformin and the ketogenic diet, was evaluated in combination with PI3K inhibition in patient-derived GBM cells and in an orthotopic GBM mouse model. Insulin feedback and the immune microenvironment were retrospectively evaluated in blood and tumor tissue from a Phase 2 clinical trial of buparlisib in patients with recurrent GBM.

RESULTS

We found that PI3K inhibition induces hyperglycemia and hyperinsulinemia in mice and that combining metformin with PI3K inhibition improves the treatment efficacy in an orthotopic GBM xenograft model. Through examination of clinical trial data, we found that hyperglycemia was an independent factor associated with poor progression-free survival in patients with GBM. We also found that PI3K inhibition increased insulin receptor activation and T-cell and microglia abundance in tumor tissue from these patients.

CONCLUSION

Reducing insulin feedback improves the efficacy of PI3K inhibition in GBM in mice, and hyperglycemia worsens progression-free survival in patients with GBM treated with PI3K inhibition. These findings indicate that hyperglycemia is a critical resistance mechanism associated with PI3K inhibition in GBM and that anti-hyperglycemic therapy may enhance PI3K inhibitor efficacy in GBM patients.

Metformin beyond an anti-diabetic agent: A comprehensive and mechanistic review on its effects against natural and chemical toxins

In addition to the anti-diabetic effect of metformin, a growing number of studies have shown that metformin has some exciting properties, such as anti-oxidative capabilities, anticancer, genomic stability, anti-inflammation, and anti-fibrosis, which have potent, that can treat other disorders other than diabetes mellitus. We aimed to describe and review the protective and antidotal efficacy of metformin against biologicals, chemicals, natural, medications, pesticides, and radiation-induced toxicities. A comprehensive search has been performed from Scopus, Web of Science, PubMed, and Google Scholar databases from inception to March 8, 2023. All in vitro, in vivo, and clinical studies were considered. Many studies suggest that metformin affects diseases other than diabetes. It is a radioprotective and chemoprotective drug that also affects viral and bacterial diseases. It can be used against inflammation-related and apoptosis-related abnormalities and against toxins to lower their effects. Besides lowering blood sugar, metformin can attenuate the effects of toxins on body weight, inflammation, apoptosis, necrosis, caspase-3 activation, cell viability and survival rate, reactive oxygen species (ROS), NF-κB, TNF-α, many interleukins, lipid profile, and many enzymes activity such as catalase and superoxide dismutase. It also can reduce the histopathological damages induced by many toxins on the kidneys, liver, and colon. However, clinical trials and human studies are needed before using metformin as a therapeutic agent against other diseases.

Anti‑inflammatory effect of metformin against an experimental model of LPS‑induced cytokine storm

Cytokine storm is one of the leading causes of death in patients with COVID-19. Metformin has been shown to inhibit the action of a wide range of proinflammatory cytokines such as IL-6, and TNF-α which may ultimately affect cytokine storm due to Covid-19. The present study analyzed the anti-inflammatory effect of oral and intraperitoneal (IP) metformin administration routes in a mouse model of lipopolysaccharide (LPS)-induced cytokine storm. A total of 60 female BALB/c mice were randomly assigned to one of six groups: i) Control; ii) LPS model; iii) oral saline + LPS; iv) oral metformin + LPS; v) IP saline + LPS; and vi) IP metformin + LPS. Metformin or saline were administered to the mice for 30 days, after which an IP injection of 0.5 mg/kg LPS induced a cytokine storm in the five treatment groups. Mice were sacrificed and serum cytokine levels were measured. Pretreatment of mice with either oral or IP metformin significantly reduced the increase in IL-1, IL-6 and TNF-α following LPS injection. Both metformin administration routes significantly reduced IL-1 and TNF-α levels, although IP metformin appeared to be significantly more effective at reducing IL-6 levels compared with oral metformin. Neither the oral or IP route of administration of metformin demonstrated a significant effect on IL-17 levels. Based on its ability to suppress the proinflammatory LPS-induced cytokine storm, metformin may have future potential benefits in ameliorating human diseases caused by elevated cytokine levels.

The Management of COVID-19-Related Coagulopathy: A Focus on the Challenges of Metabolic and Vascular Diseases

The course of COVID-19 is highly dependent on the associated cardiometabolic comorbidities of the patient, which worsen the prognosis of coronavirus infection, mainly due to systemic inflammation, endothelium dysfunction, and thrombosis. A search on the recent medical literature was performed in five languages, using the PubMed, Embase, Cochrane, and Google Scholar databases, for the review of data regarding the management of patients with a high risk for severe COVID-19, focusing on the associated coagulopathy. Special features of COVID-19 management are presented, based on the underlying conditions (obesity, diabetes mellitus, and cardiovascular diseases), emphasizing the necessity of a modern, holistic approach to thromboembolic states. The latest findings regarding the most efficient therapeutic approaches are included in the article, offering guidance for medical professionals in severe, complicated cases of SARS-CoV-2 infection. We can conclude that severe COVID-19 is closely related to vascular inflammation and intense cytokine release leading to hemostasis disorders. Overweight, hyperglycemia, cardiovascular diseases, and old age are important risk factors for severe outcomes of coronavirus infection, involving a hypercoagulable state. Early diagnosis and proper therapy in complicated SARS-CoV-2-infected cases could reduce mortality and the need for intensive care during hospitalization in patients with cardiometabolic comorbidities.

Clinically Evaluated COVID-19 Drugs with Therapeutic Potential for Biological Warfare Agents

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak resulted in hundreds of millions of coronavirus cases, as well as millions of deaths worldwide. Coronavirus Disease 2019 (COVID-19), the disease resulting from exposure to this pathogen, is characterized, among other features, by a pulmonary pathology, which can progress to "cytokine storm", acute respiratory distress syndrome (ARDS), respiratory failure and death. Vaccines are the unsurpassed strategy for prevention and protection against the SARS-CoV-2 infection. However, there is still an extremely high number of severely ill people from at-risk populations. This may be attributed to waning immune response, variant-induced breakthrough infections, unvaccinated population, etc. It is therefore of high importance to utilize pharmacological-based treatments, despite the progression of the global vaccination campaign. Until the approval of Paxlovid, an efficient and highly selective anti-SARS-CoV-2 drug, and the broad-spectrum antiviral agent Lagevrio, many pharmacological-based countermeasures were, and still are, being evaluated in clinical trials. Some of these are host-directed therapies (HDTs), which modulate the endogenic response against the virus, and therefore may confer efficient protection against a wide array of pathogens. These could potentially include Biological Warfare Agents (BWAs), exposure to which may lead to mass casualties due to disease severity and a possible lack of efficient treatment. In this review, we assessed the recent literature on drugs under advanced clinical evaluation for COVID-19 with broad spectrum activity, including antiviral agents and HDTs, which may be relevant for future coping with BWAs, as well as with other agents, in particular respiratory infections.

Metformin alleviates lung-endothelial hyperpermeability by regulating cofilin-1/PP2AC pathway

Background: Microvascular endothelial hyperpermeability is an earliest pathological hallmark in Acute Lung Injury (ALI), which progressively leads to Acute Respiratory Distress Syndrome (ARDS). Recently, vascular protective and anti-inflammatory effect of metformin, irrespective of glycemic control, has garnered significant interest. However, the underlying molecular mechanism(s) of metformin's barrier protective benefits in lung-endothelial cells (ECs) has not been clearly elucidated. Many vascular permeability-increasing agents weakened adherens junctions (AJ) integrity by inducing the reorganization of the actin cytoskeleton and stress fibers formation. Here, we hypothesized that metformin abrogated endothelial hyperpermeability and strengthen AJ integrity via inhibiting stress fibers formation through cofilin-1-PP2AC pathway. Methods: We pretreated human lung microvascular ECs (human-lung-ECs) with metformin and then challenged with thrombin. To investigate the vascular protective effects of metformin, we studied changes in ECs barrier function using electric cell-substrate impedance sensing, levels of actin stress fibers formation and inflammatory cytokines IL-1β and IL-6 expression. To explore the downstream mechanism, we studied the Ser³-phosphorylation-cofilin-1 levels in scramble and PP2AC-siRNA depleted ECs in response to thrombin with and without metformin pretreatment. Results: In-vitro analyses showed that metformin pretreatment attenuated thrombin-induced hyperpermeability, stress fibers formation, and the levels of inflammatory cytokines IL-6 and IL-β in human-lung-ECs. We found that metformin mitigated Ser³-phosphorylation mediated inhibition of cofilin-1 in response to thrombin. Furthermore, genetic deletion of PP2AC subunit significantly inhibited metformin efficacy to mitigate thrombin-induced Ser³-phosphorylation cofilin-1, AJ disruption and stress fibers formation. We further demonstrated that metformin increases PP2AC activity by upregulating PP2AC-Leu³⁰⁹ methylation in human-lung-ECs. We also found that the ectopic expression of PP2AC dampened thrombin-induced Ser³-phosphorylation-mediated inhibition of cofilin-1, stress fibers formation and endothelial hyperpermeability. Conclusion: Together, these data reveal the unprecedented endothelial cofilin-1/PP2AC signaling axis downstream of metformin in protecting against lung vascular endothelial injury and inflammation. Therefore, pharmacologically enhancing endothelial PP2AC activity may lead to the development of novel therapeutic approaches for prevention of deleterious effects of ALI on vascular ECs.

The effect of metformin on influenza vaccine responses in nondiabetic older adults: a pilot trial

BACKGROUND

Aging is associated with progressive declines in immune responses leading to increased risk of severe infection and diminished vaccination responses. Influenza (flu) is a leading killer of older adults despite availability of seasonal vaccines. Geroscience-guided interventions targeting biological aging could offer transformational approaches to reverse broad declines in immune responses with aging. Here, we evaluated effects of metformin, an FDA approved diabetes drug and candidate anti-aging drug, on flu vaccination responses and markers of immunological resilience in a pilot and feasibility double-blinded placebo-controlled study.

RESULTS

Healthy older adults (non-diabetic/non-prediabetic, age: 74.4 ± 1.7 years) were randomized to metformin (n = 8, 1500 mg extended release/daily) or placebo (n = 7) treatment for 20 weeks and were vaccinated with high-dose flu vaccine after 10 weeks of treatment. Peripheral blood mononuclear cells (PBMCs), serum, and plasma were collected prior to treatment, immediately prior to vaccination, and 1, 5, and 10 weeks post vaccination. Increased serum antibody titers were observed post vaccination with no significant differences between groups. Metformin treatment led to trending increases in circulating T follicular helper cells post-vaccination. Furthermore, 20 weeks of metformin treatment reduced expression of exhaustion marker CD57 in circulating CD4 T cells.

CONCLUSIONS

Pre-vaccination metformin treatment improved some components of flu vaccine responses and reduced some markers of T cell exhaustion without serious adverse events in nondiabetic older adults. Thus, our findings highlight the potential utility of metformin to improve flu vaccine responses and reduce age-related immune exhaustion in older adults, providing improved immunological resilience in nondiabetic older adults.

Diabetes mellitus: Lessons from COVID-19 for monkeypox infection

BACKGROUND AND AIMS

Type 2 Diabetes Mellitus is known to be linked to malfunctioning antiviral defense; however, its association with the severity of monkeypox is poorly understood. In this review, we discuss key immunological mechanisms in the antiviral response affected by poor glucose control that could impact the susceptibility and severity of monkeypox infection, leading to a heightened emphasis on the use of the available antidiabetic drugs.

METHODS

We searched PubMed and Google scholar for articles published from January 1985 to August 2022. No criteria for publication data were set, and all articles in English were included.

RESULTS

Currently, there are no studies about the risk or consequences of monkeypox infection in the diabetic population. A high incidence of diabetes is reported in countries such as China, India, Pakistan, EUA, Indonesia, Brazil, Mexico, Bangladesh, Japan, and Egypt, where unfortunately imported cases of monkeypox have been reported and the infection continues to spread.

CONCLUSIONS

High incidence of diabetes together with the cessation of smallpox vaccination has left large numbers of the human population unprotected against monkeypox. The best option for the population remains confined to the prevention of infection as well as the use of hypoglycemic agents that have also been shown to improve immune mechanisms associated with viral protection.

Psidium cattleianum fruit extract prevents systemic alterations in an animal model of type 2 diabetes mellitus: comparison with metformin effects

Objective: In this study, we aimed to determine the role of Psidium cattleianum extract (PCE) and compare its effects with those of metformin (Met) in an animal model with type 2 diabetes mellitus (T2DM).Methods: T2DM was induced in rats using a high-fat diet (HFD), followed by a single dose of streptozotocin (STZ). Met and PCE were administered intragastrically once a day throughout the experiment, and their effects on biochemical, inflammatory, oxidative, and histological parameters were evaluated.Results: Met and PCE prevented the increase in serum levels of glucose, total cholesterol (TC), triacylglycerol (TG), very low-density lipoprotein (VLDL) and interleukin-6 (IL-6) induced by T2DM, and restored redox homeostasis in the liver and brain. Met increased the serum levels of anti-inflammatory cytokine and interleukin-10 (IL-10). Furthermore, both treatments restored the liver and pancreas from marked cellular disorganisation, vacuolisation, and necrosis, with PCE being more effective than Met in recovering histological changes.Conclusion: PCE is a promising agent for the prevention of T2DM complications.

Research progress of p38 as a new therapeutic target against morphine tolerance and the current status of therapy of morphine tolerance

With the development of the medical industry, new painkillers continue to appear in people's field of vision, but so far no painkiller can replace morphine. While morphine has a strong analgesic effect, it is also easy to produce pain sensitivity and tolerance. Due to the great inter-individual differences in patient responses, there are few clear instructions on how to optimise morphine administration regimens, which complicates clinicians' treatment strategies and limits the effectiveness of morphine in long-term pain therapy. P38MAPK is a key member of the MAPK family. Across recent years, it has been discovered that p38MAPK rises dramatically in a wide range of morphine tolerance animal models. Morphine tolerance can be reduced or reversed by inhibiting p38MAPK. However, the role and specific mechanism of p38MAPK are not clear. In this review, we synthesise the relevant findings, highlight the function and potential mechanism of p38MAPK in morphine tolerance, as well as the present status and efficacy of morphine tolerance therapy, and underline the future promise of p38MAPK targeted morphine tolerance treatment.

B cells from old mice induce the generation of inflammatory T cells through metabolic pathways

We have measured the capacity of B cells from young and old mice to induce the differentiation of naïve CD4 + T cells from young mice into pro-inflammatory subsets. We found that only B cells from old mice are inflammatory and induce in vitro secretion of the pro-inflammatory cytokines IL-17A and IFN-γ by T cells. In co-culture experiments, B cells from old mice showed a strong helper function on T cells from young mice, making them pro-inflammatory, and this effect is regulated by metabolic pathways, mainly anaerobic glycolysis, leading to increased RNA expression of the enzyme lactate dehydrogenase (LDHA) and increased secretion of lactate. These results have indicated that lactate is a crucial player of the B cell-induced polarization of T cells. When we measured the effects of lactate on isolated CD4 + T cells from young mice, we found that lactate increases RNA expression of LDHA, secretion of pro-inflammatory cytokines and NF-kB activation. Moreover, lactate effects in culture can be abrogated in the presence of the specific inhibitor of LDHA, FX11. These results altogether may have relevant clinical implications and suggest novel targets for therapeutic interventions in patients with inflammatory conditions and diseases.

Design and optimization of metformin-loaded solid lipid nanoparticles for neuroprotective effects in a rat model of diffuse traumatic brain injury: A biochemical, behavioral, and histological study

BACKGROUND AND PURPOSE

Following traumatic brain injury, inflammation, mitochondrial dysfunction, oxidative stress, ischemia, and energy crisis can cause mortality or long-term morbidity. As an activator of AMP-activated protein kinase, metformin reduces the secondary injuries of traumatic brain injury by compensating for the lack of energy in damaged cells. But the blood-brain barrier prevents a hydrophilic drug such as metformin from penetrating the brain tissue. Solid lipid nanoparticles with their lipid nature can cross the blood-brain barrier and solve this challenge. so This study aimed to investigate the effect of metformin-loaded lipid nanoparticles (NanoMet) for drug delivery to the brain and reduce complications from traumatic brain injury.

METHOD

Different formulations of NanoMet were designed by Box-Behnken, and after formulation, particle size, zeta potential, and entrapment efficiency were investigated. For in vivo study, Male rats were divided into eight groups, and except for the intact and sham groups, the other groups underwent brain trauma by the Marmarou method. After the intervention, the Veterinary Coma Scale, Vestibular Motor function, blood-brain barrier integrity, cerebral edema, level of inflammatory cytokines, and histopathology of brain tissue were assessed.

RESULTS

The optimal formula had a size of 282.2 ± 9.05 nm, a zeta potential of -1.65 ± 0.33 mV, and entrapment efficiency of 60.61 ± 6.09% which released the drug in 1400 min. Concentrations of 5 and 10 mg/kg of this formula improved the consequences of trauma.

CONCLUSION

This study showed that nanoparticles could help target drug delivery to the brain and apply the desired result.

The effect of metformin or dipeptidyl peptidase 4 inhibitors on clinical outcomes in metastatic non-small cell lung cancer treated with immune checkpoint inhibitors

BACKGROUND

Preclinical data have shown the immunomodulatory effects of metformin and dipeptidyl peptidase 4 (DPP4) inhibitors in patients with diabetes. However, its clinical impact remains unclear in lung cancer.

METHODS

Between 2017 and 2021, 466 patients received ICI monotherapy. Patients were categorized into concurrent (MET; metformin or combination of metformin and DPP4 inhibitor) and without concomitant (NMET; nonmetformin/DPP4 inhibitors) administration of metformin and DPP4 inhibitors groups at least 8 weeks before and during ICI therapy. The primary objectives were the objective response rate (ORR) and progression-free survival (PFS). The second objective was to evaluate the overall survival (OS) and the occurrence of immune-related adverse events (irAEs).

RESULTS

Among 466 patients, 89 (19.0%) and 377 (81%) were categorized into the MET and NMET groups, respectively. MET group had a significantly higher ORR (MET group: 24.7% vs. NMET group: 14.8%, p = 0.025) and longer PFS than those in the NMET group (MET group 5.1 month vs. NMET group 2.8 months, p = 0.018). After patients were stratified based on the prior line of therapy and PD L1 expression status, the PFS of the second-line therapy and PD L1 ≥50 was significantly higher in the MET than in the NMET group. The proportion of patients experiencing all-grade irAEs was numerically higher in the MET group (19.1%) than in the NMET group (14.3%), without statistical significance (p = 0.382).

CONCLUSIONS

Concurrent use of metformin and DPP4 inhibitors with ICIs significantly improved the clinical outcomes without increasing the incidence of irAEs in NSCLC.

Repurposing metformin as a potential treatment for inflammatory bowel disease: Evidence from cell to the clinic

Inflammatory bowel disease (IBD) comprises a group of intestinal disorders, including ulcerative colitis and Crohn's disease. Currently, the incidence and prevalence of IBD are increasing globally. Although both biologic agents and small molecule drugs have been available for treatment of IBD patients, approximately one third of treated patients do not respond to these treatments. Therefore, novel therapy or repurposing of drugs have been extensively studied to obtain an effective therapy for IBD patients. Among these drugs, metformin has been reported to exert beneficial effects in many organs via its anti-inflammatory effect. Additionally, evidence from cellular to clinical models of IBD demonstrated significant positive effects of metformin on inflammatory pathways, oxidative stress, gut barrier integrity, and gut microbiota. In this review, the beneficial effects of metformin on IBD are comprehensively summarized and discussed using the results of in vitro, in vivo, and clinical studies. Increased understanding of these protective effects and the underlying mechanisms may pave the way for effective use of metformin in IBD patients.

Randomized Trial of Metformin, Ivermectin, and Fluvoxamine for Covid-19

BACKGROUND

Early treatment to prevent severe coronavirus disease 2019 (Covid-19) is an important component of the comprehensive response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic.

METHODS

In this phase 3, double-blind, randomized, placebo-controlled trial, we used a 2-by-3 factorial design to test the effectiveness of three repurposed drugs - metformin, ivermectin, and fluvoxamine - in preventing serious SARS-CoV-2 infection in nonhospitalized adults who had been enrolled within 3 days after a confirmed diagnosis of infection and less than 7 days after the onset of symptoms. The patients were between the ages of 30 and 85 years, and all had either overweight or obesity. The primary composite end point was hypoxemia (≤93% oxygen saturation on home oximetry), emergency department visit, hospitalization, or death. All analyses used controls who had undergone concurrent randomization and were adjusted for SARS-CoV-2 vaccination and receipt of other trial medications.

RESULTS

A total of 1431 patients underwent randomization; of these patients, 1323 were included in the primary analysis. The median age of the patients was 46 years; 56% were female (6% of whom were pregnant), and 52% had been vaccinated. The adjusted odds ratio for a primary event was 0.84 (95% confidence interval [CI], 0.66 to 1.09; P = 0.19) with metformin, 1.05 (95% CI, 0.76 to 1.45; P = 0.78) with ivermectin, and 0.94 (95% CI, 0.66 to 1.36; P = 0.75) with fluvoxamine. In prespecified secondary analyses, the adjusted odds ratio for emergency department visit, hospitalization, or death was 0.58 (95% CI, 0.35 to 0.94) with metformin, 1.39 (95% CI, 0.72 to 2.69) with ivermectin, and 1.17 (95% CI, 0.57 to 2.40) with fluvoxamine. The adjusted odds ratio for hospitalization or death was 0.47 (95% CI, 0.20 to 1.11) with metformin, 0.73 (95% CI, 0.19 to 2.77) with ivermectin, and 1.11 (95% CI, 0.33 to 3.76) with fluvoxamine.

CONCLUSIONS

None of the three medications that were evaluated prevented the occurrence of hypoxemia, an emergency department visit, hospitalization, or death associated with Covid-19. (Funded by the Parsemus Foundation and others; COVID-OUT ClinicalTrials.gov number, NCT04510194.).

N-cystaminylbiguanide MC001 prevents neuron cell death and alleviates motor deficits in the MPTP-model of Parkinson's disease

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN), which is highly associated with oxidative stress. Antioxidants are therefore considered as potential therapies in PD treatment. In this study, we examined the neuroprotective effect of a cysteamine-based biguanide N-cystaminylbiguanide (MC001) in the MPTP mouse model of PD. The results showed that MC001 prevented neuron cell death and alleviated motor deficits in the MPTP mouse model of PD. Both in vitro and in vivo data indicated that MC001 may exert its neuroprotective effect by alleviating ROS production, suppressing neuroinflammation, and upregulating BDNF expression. Further mechanistic studies revealed that MC001 promoted GSH synthesis by inducing the expression of Glutamate-cysteine ligase catalytic subunit (Gclc) and enhancing the activity of Glutamate-cysteine ligase (Gcl). Our results suggest that MC001 warrants further investigation as a potential candidate for the treatment of PD.

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 regulates macrophage polarization via the Shh signaling pathway to improve pulmonary vascular development in bronchopulmonary dysplasia

Metformin has potential anti-inflammatory properties and accelerates wound healing by enhancing vascular development. In this study, we aimed to investigate the effects of metformin on pulmonary vascular development and the underlying mechanism. Newborn mice were subcutaneously injected with metformin from day 2 after exposure to hyperoxia. Pulmonary vascular development, inflammation, and Shh signaling pathway-related protein expression were evaluated by western blotting and immunofluorescence staining. M2 macrophage polarization was measured by flow cytometry. The effect of metformin on macrophage polarization was determined using RAW264.7 macrophages exposed to 90% oxygen in vitro. The role of metformin and purmorphamine on M1 and M2 polarization was observed by flow cytometry. M2 polarization of pulmonary macrophages was inhibited after hyperoxic exposure, and metformin increased the number of M2 macrophages in the lung on postnatal day 14. Metformin upregulated CD31 expression and suppressed inflammation in the lung of mice exposed to hyperoxia on postnatal days 7 and 14. Metformin downregulated the Gli1 expression in macrophages in the lung after exposure to hyperoxia on postnatal day 14. In vitro studies showed that metformin inhibited the Gli1 expression in RAW264.7 macrophages exposed to 90% oxygen, which was reversed after purmorphamine pretreatment. Exposure to 90% oxygen inhibited the polarization of M2 macrophages, whereas metformin increased the number of M2 macrophages. Purmorphamine reversed the effects of metformin on M2 polarization and vascular endothelial growth factor (VEGF) upregulation in RAW264.7 macrophages exposed to hyperoxia. In conclusion, metformin regulates macrophage polarization via the Shh signaling pathway to improve pulmonary vascular development in bronchopulmonary dysplasia.