A Molecular Perspective on the Potential Benefits of Metformin for the Treatment of Inflammatory Skin Disorders

Metformin Therapy for Acne Vulgaris: A Meta-Analysis

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

Extensive therapeutic effects, underlying molecular mechanisms and disease treatment prediction of Metformin: a systematic review

Metformin (Met), a first-line management for type 2 diabetes mellitus, has been expansively employed and studied with results indicating its therapeutic potential extending beyond glycemic control. Beyond its established role, this therapeutic drug demonstrates a broad spectrum of action encompassing over 60 disorders, encompassing metabolic conditions, inflammatory disorders, carcinomas, cardiovascular diseases, and cerebrovascular pathologies. There is clear evidence of Met's action targeting specific nodes in the molecular pathways of these diseases and, intriguingly, interactions with the intestinal microbiota and epigenetic processes have been explored. Furthermore, novel Met derivatives with structural modifications tailored to diverse diseases have been synthesized and assessed. This manuscript proffers a comprehensive thematic review of the diseases amenable to Met treatment, elucidates their molecular mechanisms, and employs informatics technology to prospect future therapeutic applications of Met. These data and insights gleaned considerably contribute to enriching our understanding and appreciation of Met's far-reaching clinical potential and therapeutic applicability.

Efficacy and safety of metformin for melasma treatment: a systematic review and meta-analysis

Objective: Metformin has recently been demonstrated to have an anti-melanogenic activity. Nevertheless, clinical evidence of the effectiveness of metformin in melasma is lacking. The objective of this study was to assess the efficacy and safety of metformin in the treatment of melasma. Methods: MEDLINE, Embase, PubMed, Cochrane Library (CENTRAL), Scopus, CINAHL, and grey literature databases were searched to 4 October 2022 and updated on 26 February 2023. Randomized controlled trials (RCTs), quasi-RCTs, observational studies, case series, and case reports investigating the efficacy and safety of metformin for melasma were included. The Melasma Area Severity Index (MASI) scores that changed from baseline were pooled using fixed-effects model and expressed as standardized mean differences (SMDs) and 95% confidence intervals (CIs). Results: Three RCTs including 140 patients with melasma were included. The results demonstrated that after 8 weeks, 15% topical metformin significantly reduced the Melasma Area Severity Index (MASI) score compared to placebo (1 trial; n = 60; MD, -0.56; 95% CI, -1.07 to -0.04; p = 0.034). Furthermore, when compared to triple combination cream (TCC), 30% topical metformin demonstrated similar efficacy in reducing the MASI score after 8 weeks (2 trials; n = 80; MD, 0.19, 95% CI, -0.25 to 0.63; p = 0.390). Patients using 30% topical metformin had fewer adverse events compared to TCC users, although no statistical difference was found. Conclusion: Topical metformin was as effective as triple combination cream (TCC) in decreasing changes in the MASI score in patients with melasma, with minimum adverse events. Further studies with larger sample sizes, longer follow-up times, and well-designed trials are required. Systematic Review Registration: Identifier PROSPERO (CRD42022351966).

Palmatine treats urticaria by reducing inflammation and increasing autophagy

Introduction

Chronic spontaneous urticaria (CSU) is mainly manifested as wheals and erythema on the skin accompanied by itching, which will cause emotional anxiety and seriously affect the quality of life in patients. Palmatine (PAL) is a main chemical component of Yajieshaba, which has been found to effectively alleviate the symptoms of food allergy. However, its role and mechanism in CSU remain unclear. The present study aimed to investigate the protective effect of PAL on CSU rats.

Methods

We replicated the CSU rat model by intraperitoneal injection of ovalbumin (OVA) in rats on days 0, 2, 4, and 14, with a double dose given on the last challenge. PAL, loratadine and saline were given by gavage from day 5 to day 14. We observed the skin pathologic changes, mast cell degranulation, immune factor levels, inflammatory response and autophagy-related protein expression in CSU rats.

Results

We found PAL treatment to be effective in alleviating CSU-like skin lesions and reducing itching and mast cell degranulation in rats. Compared with the OVA group, the levels of immune and inflammatory factors were significantly reduced, neutrophil recruitment was alleviated, suggesting a reduced inflammatory response. The autophagy results showed that PAL further increased the expression of LC3, Beclin-1 and p-LKB1, p-AMPK, Atg5, Atg12 and Atg5-Atg12, while P62 and p-p70S6K1 expression decreased. They collectively suggested that autophagic flux was activated after PAL treatment. However, there was an increase in the expression of LC3I, probably due to the fact that PAL induced its accumulation in order to provide substrate for the generation of more LC3II.

Discussion

Overall, PAL had a protective effect on CSU in normal rats, activated the expression of autophagy and improved the inflammatory response.

Overexpression of hypoxia-inducible factor-1α in hidradenitis suppurativa: the link between deviated immunity and metabolism

Hypoxia-inducible factor-1α (HIF-1α) is the master transcription factor of glycolysis, Th17 cell differentiation and suppression of regulatory T cells. In the skin and serum of patients with psoriasis vulgaris, increased expression of HIF-1α has been reported, whereas HIF-1α expression in the skin and serum of patients with hidradenitis suppurativa (HS) has not yet been studied. The objective of the study is to demonstrate is there a role for HIF-1α in the pathogenesis of hidradenitis suppurativa, and its relation to HS severity. Twenty patients suffering from hidradenitis suppurativa were included in the study. Punch biopsies were taken from lesional skin for the determination of HIF-1α expression by immunohistochemical staining, and HIF-1α gene expression by quantitative reverse transcription real time PCR. Quantification of HIF-1α protein concentration was done by enzyme-linked immunosorbent assay. Twenty socio-demographically cross-matched healthy volunteers served as controls. We found increased serum levels of HIF-1α. Literature-derived evidence indicates that the major clinical triggering factors of HS, obesity, and smoking are associated with hypoxia and enhanced HIF-1α expression. Pro-inflammatory cytokines such as tumor necrosis factor-[Formula: see text] via upregulation of nuclear factor [Formula: see text]B enhance HIF-1α expression. HIF-1α plays an important role for keratinocyte proliferation, especially for keratinocytes of the anagen hair follicle, which requires abundant glycolysis providing sufficient precursors molecules for biosynthetic pathways. Metformin via inhibition of mTORC1 as well as adalimumab attenuate HIF-1α expression, the key mediator between Th17-driven deviated immunity and keratinocyte hyperproliferation. In accordance with psoriasis, our study identifies HS as an HIF-1α-driven inflammatory skin disease and offers a new rationale for the prevention and treatment of HS by targeting HIF-1[Formula: see text] overexpression.

Metformin Treatment of Hidradenitis Suppurativa: Effect on Metabolic Parameters, Inflammation, Cardiovascular Risk Biomarkers, and Immune Mediators

Hidradenitis suppurativa (HS) is a common cutaneous and systemic inflammatory disease with a significant impact on mental health and quality of life. It is associated with obesity, insulin resistance, metabolic syndrome, cardiovascular (CV) disease, and increased all-cause mortality. Metformin is used frequently in HS treatment and is effective for some patients. The mechanism of action of metformin in HS is unknown. A case-control study of 40 patients with HS (20 on metformin and 20 controls) was conducted to assess differences in metabolic markers, inflammation (C-reactive protein [CRP], serum adipokines, and CV risk biomarkers), and serum immune mediators. Body mass index (BMI), insulin resistance (77%), and metabolic syndrome (44%) were high overall, but not significantly different between the groups. This highlights the need for co-morbidity screening and management. A significant reduction in fasting insulin and a trend towards a reduction in insulin resistance were identified in the metformin group compared with pre-treatment levels. CV risk biomarkers were significantly favourable in the metformin group (lymphocytes, monocyte-lymphocyte ratio, neutrophil-lymphocyte ratio, and platelet-lymphocyte ratio). CRP was lower in the metformin group but was not statistically significant. Adipokines were dysregulated overall but were not different between the two groups. Serum IFN-γ, IL-8, TNF-α, and CXCL1 trended lower in the metformin group but did not reach significance. These results suggest that metformin improves CV risk biomarkers and insulin resistance in patients with HS. When the results of this study are considered alongside other studies in HS and related conditions, it is likely that metformin also has beneficial effects on metabolic markers and systemic inflammation in HS (CRP, serum adipokines, and immune mediators), warranting further research.

Adolescent acne vulgaris: current and emerging treatments

Acne vulgaris is one of the commonest inflammatory skin diseases seen worldwide, affecting all ethnicities and races, with a peak prevalence between age 15 years and 20 years. The burden of this condition, and the resulting clinical and psychological sequelae, is substantial. The visual appearance of acne and its sequelae, including scarring and pigment changes, frequently results in psychological and social morbidity because of concerns about appearance. As understanding of the pathophysiology has evolved, approaches to achieving the optimal outcomes with effective treatment regimens continue to emerge. In the past few years, several novel therapeutics have been developed, including new agents aimed at reducing antimicrobial resistance and products with specific actions targeting retinoid receptors and androgen receptors. This Review considers the management approaches of an adolescent with acne vulgaris and reviews treatment options from the evidence base and international expert opinion. Approaches to selecting current treatments and novel and emerging treatment regimens are discussed.

A novel sprayable thermosensitive hydrogel coupled with zinc modified metformin promotes the healing of skin wound

A novel sprayable adhesive is established (ZnMet-PF127) by the combination of a thermosensitive hydrogel (Pluronic F127, PF127) and a coordination complex of zinc and metformin (ZnMet). Here we demonstrate that ZnMet-PF127 potently promotes the healing of traumatic skin defect and burn skin injury by promoting cell proliferation, angiogenesis, collagen formation. Furthermore, we find that ZnMet could inhibit reactive oxygen species (ROS) production through activation of autophagy, thereby protecting cell from oxidative stress induced damage and promoting healing of skin wound. ZnMet complex exerts better effects on promoting skin wound healing than ZnCl₂ or metformin alone. ZnMet complex also displays excellent antibacterial activity against Staphylococcus aureus or Escherichia coli, which could reduce the incidence of skin wound infections. Collectively, we demonstrate that sprayable PF127 could be used as a new drug delivery system for treatment of skin injury. The advantages of this sprayable system are obvious: (1) It is convenient to use; (2) The hydrogel can cover irregular skin defect sites evenly in a liquid state. In combination with this system, we establish a novel sprayable adhesive (ZnMet-PF127) and demonstrate that it is a potential clinical treatment for traumatic skin defect and burn skin injury.

The potential role of insulin-like growth factor 1 in acne vulgaris and its correlation with the clinical response before and after treatment with metformin

BACKGROUND

Acne vulgaris (AV) is a complex and multifactorial inflammatory disease affecting the pilosebaceous follicles. Optimum treatment of AV is important to reduce the disease severity and recurrence.

AIM

To evaluate the role of metformin in the treatment of acne vulgaris by reducing the level of insulin-like growth factor 1.

METHODS

Fifty patients with AV were included in the study. Their ages ranged from 16 to 30 years, and they had different grades of the disease. IGF-1 levels were measured in all patients before and after the treatment with metformin.

RESULTS

After 4 months of therapy, there was a clinical improvement detected by an improvement in the global acne grading system (GAGS) score and also a significant decrease in IGF-level.

CONCLUSION

IGF-1 may have an important role in the pathogenesis of acne; also we can presume that oral metformin is an effective and safe line in the treatment of AV.

Protective effects of metformin in various cardiovascular diseases: Clinical evidence and AMPK-dependent mechanisms

Metformin, a well-known AMPK agonist, has been widely used as the first-line drug for treating type 2 diabetes. There had been a significant concern regarding the use of metformin in people with cardiovascular diseases (CVDs) due to its potential lactic acidosis side effect. Currently growing clinical and preclinical evidence indicates that metformin can lower the incidence of cardiovascular events in diabetic patients or even non-diabetic patients beyond its hypoglycaemic effects. The underlying mechanisms of cardiovascular benefits of metformin largely involve the cellular energy sensor, AMPK, of which activation corrects endothelial dysfunction, reduces oxidative stress and improves inflammatory response. In this minireview, we summarized the clinical evidence of metformin benefits in several widely studied cardiovascular diseases, such as atherosclerosis, ischaemic/reperfusion injury and arrhythmia, both in patients with or without diabetes. Meanwhile, we highlighted the potential AMPK-dependent mechanisms in in vitro and/or in vivo models.

Metformin Inhibits HaCaT Cell Proliferation Under Hyperlipidemia Through Reducing Reactive Oxygen Species via FOXO3 Activation

Purpose

Metformin (MET) has been proved to be effective for the treatment of psoriasis. The mechanisms of its action under the hyperlipidemia have yet to be fully elucidated. Here, we investigated the effect of metformin on the cell proliferation induced by hyperlipidemia and the underlying mechanism in immortalized human keratinocyte cell line (HaCat).

Methods

Wild-type or FOXO3 knockdown HaCat cells were treated with free fatty acids (FFA) for 10 days and then co-treated with metformin for another 4 days. Triglyceride (TG) level, cell viability, proliferation, apoptosis, antioxidant enzymes, reactive oxygen species (ROS) levels, as well as the transcription activity of FOXO3 were analyzed.

Results

Metformin decreased HaCaT cell proliferation and induced cell apoptosis after FFA treatment. Metformin was found to significantly increase the expressions and the activities of superoxide dismutase (SOD) as well as catalase (CAT), and reduced the reactive oxygen species (ROS) level. Metformin significantly promoted the autophagy and increase FOXO3 protein level in the nucleus under hyperlipidemia. However, all of the effects from metformin were partially blocked by FOXO3 knockdown.

Conclusion

This study demonstrated that under the hyperlipidemia, metformin has significant antiproliferation and proapoptosis effects by reducing ROS level as well as increasing autophagy. All of these effects from metformin were through FOXO3-dependent pathway.

Diabetic Muscular Atrophy: Molecular Mechanisms and Promising Therapies

Diabetes mellitus (DM) is a typical chronic disease that can be divided into 2 types, dependent on insulin deficiency or insulin resistance. Incidences of diabetic complications gradually increase as the disease progresses. Studies in diabetes complications have mostly focused on kidney and cardiovascular diseases, as well as neuropathy. However, DM can also cause skeletal muscle atrophy. Diabetic muscular atrophy is an unrecognized diabetic complication that can lead to quadriplegia in severe cases, seriously impacting patients' quality of life. In this review, we first identify the main molecular mechanisms of muscle atrophy from the aspects of protein degradation and synthesis signaling pathways. Then, we discuss the molecular regulatory mechanisms of diabetic muscular atrophy, and outline potential drugs and treatments in terms of insulin resistance, insulin deficiency, inflammation, oxidative stress, glucocorticoids, and other factors. It is worth noting that inflammation and oxidative stress are closely related to insulin resistance and insulin deficiency in diabetic muscular atrophy. Regulating inflammation and oxidative stress may represent another very important way to treat diabetic muscular atrophy, in addition to controlling insulin signaling. Understanding the molecular regulatory mechanism of diabetic muscular atrophy could help to reveal new treatment strategies.

Killing Two Birds with One Stone: Potential Therapies Targeting Psoriasis and Atherosclerosis at the Same Time

Psoriasis is a chronic systemic inflammatory disease. Due to systemic inflammation, it is associated with many comorbidities. Among them, cardiovascular diseases represent the most common causes of morbidity and mortality in this population. Therefore, physicians treating patients with psoriasis should keep in mind that, as important as the treatment of psoriasis, awareness of cardiovascular risk deserves additional attention. Thus, in parallel with psoriasis treatment, a cardiovascular risk assessment must also be performed and addressed accordingly. In addition to encouraging non-pharmacologic strategies for a healthy lifestyle, physicians should be familiar with different pharmacologic options that can target psoriasis and reduce cardiovascular risk. In the present article, we present the pathophysiological mechanisms of the psoriasis and cardiometabolic interplay, our view on the interaction of psoriasis and cardiovascular disease, review the atherosclerotic effect of therapeutic options used in psoriasis, and vice versa, i.e., what the effect of medications used in the prevention of atherosclerosis could be on psoriasis.

Metformina en el tratamiento de enfermedades dermatológicas: una revisión narrativa

Objetivo

Revisar y discutir la evidencia actual del uso de la metformina como herramienta terapéutica en enfermedades cutáneas.

Diseño

Artículo original. Investigación cualitativa. Revisión narrativa.

Emplazamiento

Aragón y Murcia, España.

Participantes

Médicos Internos Residentes de Dermatología Médico-Quirúrgica y Venereología y de Atención Primaria y Comunitaria.

Métodos

Se ha realizado una revisión narrativa utilizando la base de datos bibliográfica PubMed con fecha de búsqueda el 27 de enero de 2022.

Resultados

La metformina ha demostrado ser efectiva en el tratamiento de dermatosis inflamatorias tales como el acné, hidrosadenitis supurativa, psoriasis y dermatitis de contacto alérgica. También ha demostrado propiedades antitumorales frente al carcinoma basocelular, carcinoma espinocelular y melanoma. De forma adicional, se ha descrito efectos beneficiosos del tratamiento adyuvante con metformina en pacientes con carcinoma basocelular que reciben terapia fotodinámica. En pacientes con dermatosis relacionadas con endocrinopatías tales como el hirsutismo, la acantosis nigricans y los xantomas eruptivos, el tratamiento con metformina ha demostrado efectividad terapéutica. El tratamiento tópico con metformina ha demostrado ser eficaz en el tratamiento del melasma. Finalmente se ha propuesto como un fármaco con propiedades antienvejecimiento cutáneo y favorecedoras de la cicatrización. Para ninguna de las indicaciones previamente descritas se han objetivado efectos adversos graves.

Conclusiones

La metformina es un tratamiento efectivo y seguro en el esquema terapéutico de dermatosis inflamatorias, neoplasias cutáneas, dermatosis relacionadas con endocrinopatías, melasma, envejecimiento cutáneo y cicatrización.

Repurposing approved therapeutics for new indication: Addressing unmet needs in psoriasis treatment

Psoriasis is a chronic inflammatory autoimmune condition manifested by the hyperproliferation of keratinocytes with buildup of inflammatory red patches and scales on skin surfaces. The available treatment options for the management of psoriasis have various drawbacks, and the clinical need for effective therapeutics for this disease remain unmet; therefore, the approaches of drug repurposing or drug repositioning could potentially be used for treating indications of psoriasis. The undiscovered potential of drug repurposing or repositioning compensates for the limitations and hurdles in drug discovery and drug development processes. Drugs initially approved for other indications, including anticancer, antidiabetic, antihypertensive, and anti-arthritic activities, are being investigated for their potential in psoriasis management as a new therapeutic indication by using repurposing strategies. This article envisages the potential of various therapeutics for the management of psoriasis.

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Psoriasis is an autoimmune inflammatory skin disorder with complex physiology.

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Conventional treatments for psoriasis cause severe adverse effects; therefore an unmet need remains for safer and more effective therapies for psoriasis.

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Various drugs that effectively decrease the inflammation and proliferation of skin cells can be repurposed for the management of psoriasis.

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Repurposed drugs provide various incentives to the pharmaceutical industry.

Dual anticancer role of metformin: an old drug regulating AMPK dependent/independent pathways in metabolic, oncogenic/tumorsuppresing and immunity context

Metformin has been known to treat type 2 diabetes for decades and is widely prescribed antidiabetic drug. Recently, its anticancer potential has also been discovered. Moreover, metformin has low cost thus it has attained profound research interest. Comprehensing the complexity of the molecular regulatory networks in cancer provides a mode for advancement of research in cancer development and treatment. Metformin targets many pathways that play an important role in cancer cell survival outcome. Here, we described anticancer activity of metformin on the AMPK dependent/independent mechanisms regulating metabolism, oncogene/tumor suppressor signaling pathways together with the issue of clinical studies. We also provided brief overwiev about recently described metformin's role in cancer immunity. Insight in these complex molecular networks, will simplify application of metformin in clinical trials and contribute to improvement of anti-cancer therapy.

Potential Therapeutic Approaches through Modulating the Autophagy Process for Skin Barrier Dysfunction

Autophagy is an attractive process to researchers who are seeking novel potential treatments for various diseases. Autophagy plays a critical role in degrading damaged cellular organelles, supporting normal cell development, and maintaining cellular homeostasis. Because of the various effects of autophagy, recent human genome research has focused on evaluating the relationship between autophagy and a wide variety of diseases, such as autoimmune diseases, cancers, and inflammatory diseases. The skin is the largest organ in the body and provides the first line of defense against environmental hazards, including UV damage, chemical toxins, injuries, oxidative stress, and microorganisms. Autophagy takes part in endogenous defense mechanisms by controlling skin homeostasis. In this manner, regulating autophagy might contribute to the treatment of skin barrier dysfunctions. Various studies are ongoing to elucidate the association between autophagy and skin-related diseases in order to find potential therapeutic approaches. However, little evidence has been gathered about the relationship between autophagy and the skin. In this review, we highlight the previous findings of autophagy and skin barrier disorders and suggest potential therapeutic strategies. The recent research regarding autophagy in acne and skin aging is also discussed.

The Effect of Metformin in Diabetic and Non-Diabetic Rats with Experimentally-Induced Chronic Kidney Disease

This work aimed to investigate whether treatment with the antidiabetic drug metformin would affect adenine-induced chronic kidney disease (CKD) in non-diabetic rats and rats with streptozotocin (STZ)-induced diabetes. Rats were randomly divided into eight groups, and given either normal feed, or feed mixed with adenine (0.25% w/w, for five weeks) to induce CKD. Some of these groups were also simultaneously treated orally with metformin (200 mg/kg/day). Rats given adenine showed the typical signs of CKD that included detrimental changes in several physiological and traditional and novel biochemical biomarkers in plasma urine and kidney homogenates such as albumin/creatinine ratio, N-acetyl-beta-D-glucosaminidase, neutrophil gelatinase-associated lipocalin, 8-isoprostane, adiponectin, cystatin C, as well as plasma urea, creatinine, uric acid, indoxyl sulfate, calcium, and phosphorus. Several indices of inflammation and oxidative stress, and renal nuclear factor-κB and nuclear factor erythroid 2-related factor 2 levels were also measured. Histopathologically, adenine caused renal tubular necrosis and fibrosis. The activation of the intracellular mitogen-activated protein kinase signaling pathway was inhibited in the groups that received metformin and STZ together, with or without adenine induced-CKD. Induction of diabetes worsened most of the actions induced by adenine. Metformin significantly ameliorated the renal actions induced by adenine and STZ when these were given singly, and more so when given together. The results suggest that metformin can be a useful drug in attenuating the progression of CKD in both diabetic and non-diabetic rats.

Is Metformin a Possible Beneficial Treatment for Psoriasis? A Scoping Review

Psoriasis is a chronic inflammatory condition with genetic, immunological, and metabolic etiology. The link between psoriasis and diabetes mellitus has been shown in genetic predisposition, environmental influences, inflammatory pathways, and insulin resistance, resulting in end-organ damage in both conditions. Because comorbidities often accompany psoriasis, the therapeutic management of the disease must also take into consideration the comorbidities. Given that metformin’s therapeutic role in psoriasis is not yet fully elucidated, we raised the question of whether metformin is a viable alternative for the treatment of psoriasis. We conducted this scoping review by searching for evidence in PubMed, Cochrane, and Scopus databases, and we used an extension for scoping reviews (PRISMA-ScR). Current evidence suggests that metformin is safe to use in psoriasis. Studies have shown an excellent therapeutic response to metformin in patients with psoriasis and comorbidities such as diabetes, metabolic syndrome, and obesity. There is no clear evidence supporting metformin monotherapy in patients with psoriasis without comorbidities. There is a need to further evaluate metformin in larger clinical trials, as a therapy in psoriasis.