Metformin and Diammonium Glycyrrhizinate Enteric-Coated Capsule versus Metformin Alone versus Diammonium Glycyrrhizinate Enteric-Coated Capsule Alone in Patients with Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus

A Review of Metabolic Dysregulation in Lymphocytic Cicatricial Alopecia: Exploring the Connections and Therapeutic Implications

Lymphocytic primary cicatricial alopecia (LPCA) is an inflammatory disorder characterized by permanent hair follicle destruction and fibrosis. Recent evidence suggests a significant link between LPCA and metabolic dysregulation, particularly diabetes and dyslipidemia. This review examines the emerging role of metabolism in LPCA pathogenesis and its implications for novel therapeutic approaches. Epidemiologic studies demonstrate increased prevalence of metabolic disorders among patients with LPCA, whereas molecular investigations reveal altered metabolic pathways in affected hair follicles, including disruptions in peroxisome proliferator-activated receptor γ signaling and adenosine monophosphate-activated protein kinase activation, mechanisms that parallel those observed in other fibrotic diseases. These pathways appear to precede inflammatory changes, suggesting metabolic dysfunction as a primary trigger rather than a secondary effect. Preliminary treatments targeting these pathways, such as pioglitazone and metformin, have shown promising results in normalizing lipid metabolism and reducing inflammation, although their clinical efficacy across LPCA subtypes requires further investigation. The review also explores emerging therapeutic possibilities, including glucagon-like peptide-1 agonists. Understanding the interplay between metabolic disturbances, fibrosis, and inflammation in the pathogenesis of LPCA offers new avenues for both research and treatment. This paradigm shift suggests the need for metabolic screening in patients with LPCA and highlights the potential for developing more comprehensive, metabolism-targeted therapies to improve outcomes in these challenging hair disorders.

Diammonium glycyrrhizinate ameliorates alcohol-induced liver injury by reducing oxidative stress, steatosis, and inflammation

Alcohol-induced liver injury (ALI) is a serious global health issue. Diammonium glycyrrhizinate (DG), a pharmaceutical form of glycyrrhizic acid, has been reported to have anti-inflammatory and anti-oxidative stress properties. We investigated the potential hepatoprotective effects of DG against ALI and explored the mechanisms of it. In vivo, C57BL/6J mice were used to investigate the protective effect of DG on ALI induced by chronic plus binge alcohol exposure. In vitro, AML-12 cells were applied to evaluate the role of DDX5 in the hepatic protection of DG and explore the possible mechanism of STAT1 activation regulated by DDX5. The results showed that DG significantly alleviated liver injury, inflammation, and lipid deposition in hepatocytes. It also beneficially influenced oxidative stress dysregulation. RNA-seq expression in mouse liver tissue indicated that Dead-box helicase 5 (DDX5) might be a potential target of DG. Compared with the control group, the expression of DDX5 decreased significantly in the ethanol-fed group, while DDX5 was restored in the DG treatment group. In addition, the protective effects of DG against ALI were impaired by DDX5 deficiency. DDX5 inhibited the phosphorylation of signal transducer and activator of transcription 1 (STAT1) by recruiting the protein inhibitor of activated STAT1 (PIAS1) to STAT1. The protective effect of DG against ALI associated with oxidative stress, steatosis, and inflammation was probably via regulating the DDX5/STAT1 axis.

Low-Dose Metformin and Profibrotic Signature in Central Centrifugal Cicatricial Alopecia

Importance

Central centrifugal cicatricial alopecia (CCCA) is a scarring alopecia predominantly affecting Black female individuals. Current conventional treatments target inflammation but not the underlying fibrotic processes, often leading to permanent hair loss.

Objective

To investigate the associations of low-dose oral metformin, an antidiabetic medication with antifibrotic properties, with clinical symptoms and scalp gene expression patterns in patients with CCCA.

Design, Setting, and Participants

This retrospective clinical case series and transcriptomic analysis included patients treated at a single tertiary academic medical center between January 2023 and March 2024. All patients had biopsy-confirmed CCCA refractory to standard treatments. Transcriptomic analysis was performed on patients with previously banked, paired scalp biopsies before and after treatment with adjuvant metformin for at least 6 weeks.

Exposure

Extended-release metformin, 500 mg, once daily was added to participants' baseline CCCA treatment regimens.

Main Outcomes and Measures

Clinical assessments included pruritus, inflammation, scalp resistance, and hair regrowth. Gene expression profiling via bulk RNA sequencing analysis evaluated differential gene expression and pathway enrichment.

Results

A total of 12 Black female participants were included in the study, and transcriptomic analysis was performed in 4 participants. After at least 6 months of metformin treatment, 9 participants experienced improvement in disease, including scalp pain, inflammation, and/or pruritus, and 6 demonstrated clinical evidence of hair regrowth. The addition of metformin led to reversal of many prominent gene pathways previously identified in CCCA. Transcriptomic analysis revealed upregulation of pathways and genes (keratin-associated proteins [KRTAPs]) involved in keratinization, epidermis development, and the hair cycle (absolute log2-fold change > 4), with concomitant downregulation of fibrosis-related pathways and genes (eg, MMP7, COL6A1) (fold change >1.5; all false discovery rate <.05). Gene set analysis showed reduced expression of helper T cell 17 and epithelial-mesenchymal transition pathways and elevated adenosine monophosphate kinase signaling and KRTAPs after metformin treatment.

Conclusions and Relevance

In this case series of patients with treatment-refractory CCCA, low-dose oral metformin was associated with symptomatic improvement and dual modulation of gene expression, stimulating hair growth pathways while suppressing fibrosis and inflammation markers. These findings provide a rationale for future clinical trials studying metformin as a targeted therapy for CCCA and other cicatricial alopecias.

Metformin: Beyond Type 2 Diabetes Mellitus

Metformin was developed from an offshoot of Guanidine. It is known to be the first-line medication for type 2 diabetes mellitus, polycystic ovarian syndrome, and weight reduction. Metformin has also been shown to have effectiveness in the management of non-alcoholic fatty liver disease (NAFLD), liver cirrhosis, and various carcinomas like hepatocellular, colorectal, prostate, breast, urinary bladder, blood, melanoma, bone, skin, lung and so on. This narrative review focuses on the effect of metformin on non-alcoholic fatty liver disease, liver cirrhosis, and hepatocellular carcinoma. The search platforms for the topic were PubMed, Scopus, and Google search engine. Critical words for searching included 'Metformin,' AND 'Indications of Metformin,' AND 'Non-Alcoholic Fatty Liver Disease,' AND 'Metformin mechanism of action,' AND 'NAFLD management,' AND 'NAFLD and inflammation,' AND 'Metformin and insulin,' AND 'Metformin and inflammation,' AND 'Liver cirrhosis,' AND 'Hepatocellular carcinoma.' Lifestyle modification and the use of hypoglycemic agents can help improve liver conditions. Metformin has several mechanisms that enhance liver health, including reducing reactive oxygen species, nuclear factor kappa beta (NF-κB), liver enzymes, improving insulin sensitivity, and improving hepatic cell lipophagy. Long-term use of metformin may cause some adverse effects like lactic acidosis and gastrointestinal disturbance. Metformin long-term overdose may lead to a rise in hydrogen sulfide in liver cells, which calls for pharmacovigilance. Drug regulating authorities should provide approval for further research, and national and international guidelines need to be developed for liver diseases, perhaps with the inclusion of metformin as part of the management regime.

Licorice and liver function in patients with primary liver disease: A systematic review and meta-analysis of RCTs

Licorice (Glycyrrhiza spp.) has been a cornerstone of traditional Chinese and Japanese medicine. This systematic review and meta-analysis aimed to evaluate the efficacy of licorice formulations, alone or in combination with other herbs, on liver function enzymes in patients with primary liver disease. We systematically searched MEDLINE, Embase, Scopus, Web of Science, and Cochrane Library up to April 2024. Randomized controlled trials (RCTs) comparing the effects of Glycyrrhiza spp. preparations versus placebo or standard of care controls were included. Standard Cochrane methods were used to extract data and appraise eligible studies. A total of 15 RCTs, involving 1367 participants, were included in the analysis. The studies varied widely in geographical location, duration, and licorice preparations used. Licorice significantly reduced alanine aminotransferase (ALT) by 15.63 U/L (95% CI: -25.08, -6.18; p = 0.001) and aspartate aminotransferase (AST) by 7.37 U/L (95% CI: -13.13, -1.61; p = 0.01) compared to control groups. Subgroup analyses revealed that purified glycyrrhizic acid compounds were particularly effective, showing greater reductions in ALT and AST without significant heterogeneity. Although licorice treatment did not significantly impact gamma-glutamyl transferase and total bilirubin (TBIL) levels overall, specific licorice-herb preparations did show a notable reduction in TBIL. The safety profile of licorice was consistent with known side effects, predominantly mild and related to its mineralocorticoid effects. Despite heterogeneity and potential language bias, the findings suggest that licorice can enhance liver function. Further studies should standardize licorice preparations and explore its role in multifaceted herbal formulations to better understand its hepatoprotective mechanisms.

Regulation of Fructose Metabolism in Nonalcoholic Fatty Liver Disease

Elevations in fructose consumption have been reported to contribute significantly to an increased incidence of obesity and metabolic diseases in industrial countries. Mechanistically, a high fructose intake leads to the dysregulation of glucose, triglyceride, and cholesterol metabolism in the liver, and causes elevations in inflammation and drives the progression of nonalcoholic fatty liver disease (NAFLD). A high fructose consumption is considered to be toxic to the body, and there are ongoing measures to develop pharmaceutical therapies targeting fructose metabolism. Although a large amount of work has summarized the effects fructose exposure within the intestine, liver, and kidney, there remains a gap in our knowledge regarding how fructose both indirectly and directly influences immune cell recruitment, activation, and function in metabolic tissues, which are essential to tissue and systemic inflammation. The most recent literature demonstrates that direct fructose exposure regulates oxidative metabolism in macrophages, leading to inflammation. The present review highlights (1) the mechanisms by which fructose metabolism impacts crosstalk between tissues, nonparenchymal cells, microbes, and immune cells; (2) the direct impact of fructose on immune cell metabolism and function; and (3) therapeutic targets of fructose metabolism to treat NAFLD. In addition, the review highlights how fructose disrupts liver tissue homeostasis and identifies new therapeutic targets for treating NAFLD and obesity.

Myeloid AMPK signaling restricts fibrosis but is not required for metformin improvements during CDAHFD-induced NASH in mice

Metabolic programming underpins inflammation and liver macrophage activation in the setting of chronic liver disease. Here, we sought to identify the role of an important metabolic regulator, AMP-activated protein kinase (AMPK), specifically within myeloid cells during the progression of non-alcoholic steatohepatitis (NASH) and whether treatment with metformin, a firstline therapy for diabetes and activator of AMPK could stem disease progression. Male and female Prkaa1fl/fl/Prkaa2fl/fl (Flox) control and Flox-LysM-Cre+ (MacKO) mice were fed a low-fat control or a choline-deficient, amino acid defined 45% Kcal high-fat diet (CDAHFD) for 8 weeks, where metformin was introduced in the drinking water (50 or 250 mg/kg/day) for the last 4 weeks. Hepatic steatosis and fibrosis were dramatically increased in response to CDAHFD-feeding compared to low-fat control. While myeloid AMPK signaling had no effect on markers of hepatic steatosis or circulating markers, fibrosis as measured by total liver collagen was significantly elevated in livers from MacKO mice, independent of sex. Although treatment with 50 mg/kg/day metformin had no effect on any parameter, intervention with 250 mg/kg/day metformin completely ameliorated hepatic steatosis and fibrosis in both male and female mice. While the protective effect of metformin was associated with lower final body weight, and decreased expression of lipogenic and Col1a1 transcripts, it was independent of myeloid AMPK signaling. These results suggest that endogenous AMPK signaling in myeloid cells, both liver-resident and infiltrating, acts to restrict fibrogenesis during CDAHFD-induced NASH progression but is not the mechanism by which metformin improves markers of NASH.

The role of anti-diabetic drugs in NAFLD. Have we found the Holy Grail? A narrative review

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) has become a leading cause of liver disease, affecting 30% of the global population. NAFLD prevalence is particularly high in obese individuals and patients with type 2 diabetes mellitus (T2DM). NAFLD ranges from simple fat deposition in the liver to necroinflammation and fibrosis (non-alcoholic steatohepatitis (NASH)), NASH-cirrhosis, and/or hepatocellular carcinoma. Insulin resistance plays a key role in NAFLD pathogenesis, alongside dysregulation of adipocytes, mitochondrial dysfunction, genetic factors, and changes in gut microbiota. Since insulin resistance is also a major predisposing factor of T2DM, the administration of anti-diabetic drugs for the management of NAFLD seems reasonable.

METHODS

In this review we provide the NAFLD-associated mechanisms of action of some of the most widely used anti-diabetic drugs, namely metformin, pioglitazone, sodium-glucose transport protein-2 inhibitors (SGLT2i), glucagon-like peptide 1 receptor analogs (GLP1 RAs), and dipeptyl-peptidase-4 inhibitors (DPP4i) and present available data regarding their use in patients with NAFLD, with and without T2DM.

RESULTS

Both metformin and DPP4i have shown rather contradictory results, while pioglitazone seems to benefit patients with NASH and is thus the only drug approved for NASH with concomitant significant liver fibrosis by all major liver societies. On the other hand, SGLT2i and GLP1 RAs seem to be beneficiary in patients with NAFLD, showing both remarkable results, with SGLT2i proving to be more efficient in the only head-to-head study so far.

CONCLUSION

In patients with NAFLD and diabetes, pioglitazone, GLP1 RAs, and SGLT2i seem to be logical treatment options. Larger studies are needed before these drugs can be recommended for non-diabetic individuals.

PPAR-alpha/gamma agonists, glucagon-like peptide-1 receptor agonists and metformin for non-alcoholic fatty liver disease: A network meta-analysis

OBJECTIVE

To undertake a network meta-analysis to compare the relative efficacy of a dual peroxisome proliferator-activated receptor (PPAR)α and PPARγ agonist, glucagon-like peptide-1 receptor agonists (GLP-1RAs) and metformin in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

Electronic databases, including Embase®, PubMed® and The Cochrane Library, were searched systematically for eligible studies from inception to 20 July 2022. Randomized controlled trials (RCTs) that investigated aspartate aminotransferase, alanine aminotransferase (ALT) and triglyceride levels were considered for inclusion. Data were extracted using a standardized data collection table. A network meta-analysis was performed. Relative risk and 95% confidence interval were calculated for continuous data and I2 was used to assess the heterogeneity of studies.

RESULTS

A total of 22 RCTs involving 1698 patients were eligible for inclusion in the analysis. Both direct analysis and indirect analysis showed that saroglitazar was significantly superior to GLP-1RAs in improving ALT levels. Metformin improved ALT levels, but the effect was not as good as saroglitazar.

CONCLUSION

Saroglizatar was the most effective drug for improving NAFLD.INPLASY registration number: INPLASY202340066.

Research progress of metformin in the treatment of liver fibrosis

Liver fibrosis is a disease with significant morbidity and mortality. It is a chronic pathological process characterized by an imbalance of extracellular matrix production and degradation in liver tissue. Metformin is a type of hypoglycemic biguanide drug, which can be used in the treatment of liver fibrosis, but its anti-fibrotic effect and mechanism of action are unclear. The purpose of this article is to review the research progress of metformin in the treatment of liver fibrosis and to provide a theoretical basis for its application in the treatment of liver fibrosis.

Glycyrrhizic Acid and Its Derivatives: Promising Candidates for the Management of Type 2 Diabetes Mellitus and Its Complications

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease, which is characterized by hyperglycemia, chronic insulin resistance, progressive decline in β-cell function, and defect in insulin secretion. It has become one of the leading causes of death worldwide. At present, there is no cure for T2DM, but it can be treated, and blood glucose levels can be controlled. It has been reported that diabetic patients may suffer from the adverse effects of conventional medicine. Therefore, alternative therapy, such as traditional Chinese medicine (TCM), can be used to manage and treat diabetes. In this review, glycyrrhizic acid (GL) and its derivatives are suggested to be promising candidates for the treatment of T2DM and its complications. It is the principal bioactive constituent in licorice, one type of TCM. This review comprehensively summarized the therapeutic effects and related mechanisms of GL and its derivatives in managing blood glucose levels and treating T2DM and its complications. In addition, it also discusses existing clinical trials and highlights the research gap in clinical research. In summary, this review can provide a further understanding of GL and its derivatives in T2DM as well as its complications and recent progress in the development of potential drugs targeting T2DM.

Effects of Metformin on Hepatic Steatosis in Adults with Nonalcoholic Fatty Liver Disease and Diabetes: Insights from the Cellular to Patient Levels

Nonalcoholic fatty liver disease (NAFLD) patients with diabetes constitute a subgroup of patients with a high rate of liver-related complications. Currently, there are no specific drug recommendations for these patients. Metformin, a conventional insulin sensitizer agent, has been widely prescribed in patients with diabetes. Metformin treatment has been shown to be effective at alleviating hepatic lipogenesis in animal models of NAFLD, with a variety of mechanisms being deemed responsible. To date, most studies have enrolled diabetic patients who are treated with metformin, with the drug being taken continuously throughout the study. Although evidence exists regarding the benefits of metformin for NAFLD in preclinical studies, reports on the efficacy of metformin in adult NAFLD patients have had some discrepancies regarding changes in liver biochemistry and hepatic fat content. Evidence has also suggested possible effects of metformin as regards the prevention of hepatocellular carcinoma tumorigenesis. This review was performed to comprehensively summarize the available in vitro, in vivo and clinical studies regarding the effects of metformin on liver steatosis for the treatment of adult NAFLD patients with diabetes. Consistent reports as well as controversial findings are included in this review, and the mechanistic insights are also provided. In addition, this review focuses on the efficacy of metformin as a monotherapy and as a combined therapy with other antidiabetic medications.

Diammonium glycyrrhizinate lipid ligand ameliorates lipopolysaccharide-induced acute lung injury by modulating vascular endothelial barrier function

The aim of the present study was to investigate the effects of diammonium glycyrrhizinate lipid ligand (DGLL) treatment on acute lung injury (ALI) and pulmonary edema induced by lipopolysaccharide (LPS) in Sprague-Dawley rats. Rats orally received 30, 60 and 120 mg/kg DGLL. After 1 h, the rat ALI model was established by LPS (10 mg/kg) intraperitoneal injection. After 6 h, lung injury was evaluated using hematoxylin and eosin staining techniques. Pulmonary edema was evaluated using lung wet-dry weight ratio, protein concentrations in the bronchoalveolar lavage fluid (BALF) and Evans blue (EB) extravasation in lung tissue. The expression levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in lung tissues were measured using ELISA. Myeloperoxidase (MPO) expression levels were detected by immunohistochemical staining. Western blotting was used to measure the expression level changes of intercellular adhesion molecule (ICAM)-1, as well as adherent and tight junction proteins, including vascular endothelial (VE)-cadherin, zonula occludens (ZO)-1, occludin and junctional adhesion molecule (JAM)-1 that were associated with pulmonary inflammation and microvascular permeability. DGLL treatment significantly alleviated ALI induced by LPS, which was demonstrated by reduction of MPO-positive cells and expression levels of TNF-α, IL-1β and ICAM-1 in rat lung tissues. In addition, DGLL abrogated LPS-induced pulmonary edema, decreased the protein concentration in BALF and reduced EB extravasation. DGLL also reversed the reduced expression of VE-cadherin and tight junction proteins, including ZO-1, occludin and JAM-1 in the lung tissues caused by LPS. In conclusion, DGLL exhibits a protective effect on LPS-induced rat ALI, which is associated with the inhibition of inflammatory cell infiltration and microvascular barrier disruption. The present results provide a theoretical basis for the application of DGLL for the potential clinical treatment of ALI.

Diammonium Glycyrrhizinate Protects against Nonalcoholic Fatty Liver Disease in Mice through Modulation of Gut Microbiota and Restoration of Intestinal Barrier

Nonalcoholic fatty liver disease (NAFLD), as a common chronic liver disorder, is prevalent in the world. Recent evidence demonstrates that the "gut-liver axis" is related well to the progression of NAFLD, which regards gut microbiota and the intestinal barrier as two critical factors correlated with NAFLD. Diammonium glycyrrhizinate (DG), a compound of the natural bioactive pentacyclic triterpenoid glycoside, is the main component of licorice root extracts. The anti-inflammatory and liver protection effects of DG have already been reported, but to date, the mechanism has not been fully elucidated. In this research, we observed that DG reduced body weight, liver steatosis, as well as hepatic inflammation in NAFLD model mice induced by a high-fat diet. Illumina sequencing of the 16S rRNA revealed that DG intervention notably altered the composition of the gut microbiota in NAFLD mice. The richness of gut microbiota was significantly increased by DG. Specifically, DG reduced the Firmicutes-to- Bacteroidetes ratio and the endotoxin-producing bacteria such as Desulfovibrio and elevated the abundance of probiotics such as Proteobacteria and Lactobacillus. DG could augment the levels of short-chain fatty acid (SCFA)-producing bacteria such as Ruminococcaceae and Lachnospiraceae and promote SCFA production. In addition, DG supplementation dramatically alleviated the intestinal low-grade inflammation. Meanwhile, DG improved the expression of tight junction proteins, the goblet cell number, and mucin secretion and sequentially enhanced the function of intestinal barrier. Collectively, the prevention of NAFLD by DG might be mediated by modulating gut microbiota and restoring the intestinal barrier.