Miglitol attenuates non-alcoholic steatohepatitis in diabetic patients

Miglitol, an Oral Antidiabetic Drug, Downregulates Melanogenesis in B16F10 Melanoma Cells through the PKA, MAPK, and GSK3β/β-Catenin Signaling Pathways

Hyperpigmentation is a common condition that causes darker spots or patches on the skin, which often look brown, black, gray, red, or pink. This results in unresolved psychological impact due to high anxiety, depression, and somatoform disorder. We aimed to repurpose an antidiabetic drug, miglitol, as an effective compound against hyperpigmentation when applied as a cosmeceutical agent. The present study investigated the antimelanogenic effects of miglitol and the trehalase inhibitor validamycin A. Miglitol in isolation exhibited no cytotoxicity and significantly reduced the melanin production and intracellular tyrosinase activity in B16F10 melanoma cells. The Western blotting results showed that miglitol reduces the expression of melanogenic regulatory factors, including tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2, and microphthalmia-associated transcription factor (MITF). Mechanistically, miglitol appears to suppress melanin synthesis through cAMP-dependent protein kinase (PKA)-dependent downregulation of MITF, a master transcription factor in melanogenesis. The antimelanogenic effects of miglitol was mediated by downregulation of the p38 signaling pathway and upregulation of extracellular signal-regulated kinase (ERK). Moreover, miglitol decreases P-GSK3β and β-catenin levels compared to those in the untreated group. However, miglitol activated P-β-catenin expression compared to that in the untreated group. Finally, we tested the potential of miglitol in topical application through primary human skin irritation tests on the normal skin (upper back) of 33 volunteers. In these assays, miglitol (125 and 250 μM) did not induce any adverse reactions. Taken together, these findings suggest that the regulation of melanogenesis by miglitol may be mediated by the PKA, MAPK, and GSK3β/β-Catenin signaling pathways and that miglitol might provide new insights into drug repurposing for the treatment of hyperpigmentation symptoms.

The effects of the voglibose on non-alcoholic fatty liver disease in mice model

The α-glucosidase inhibitor (α-GI) delays the intestinal absorption of glucose, which reduces postprandial hepatic glucose intake. This mechanism is considered to be effective in treating non-alcoholic fatty liver disease (NAFLD). Here, we investigated the effect of voglibose, an α-glucosidase inhibitor, on high-fat, high-fructose (HFHFr) diet-induced NAFLD models. Seven-week-old male C57BL/6J mice were randomly placed in a chow diet group or an HFHFr diet group. After 10 weeks, mice in the HFHFr group were randomly assigned to one of three groups: HFHFr diet with vehicle, HFHFr with voglibose, or HFHFr with pioglitazone. Each diet and treatment was continued for 10 weeks. The HFHFr diet induced severe NAFLD in terms of steatosis, hepatitis, and fibrosis. Administration of voglibose improved all aspects of NAFLD, comparable to those of pioglitazone, a positive control. In voglibose-treated mice, gene expressions of hepatic lipogenesis markers were significantly downregulated. In the in vitro experiment, reducing the influx of glucose into hepatocytes significantly reduced steatosis and de novo lipogenesis even in the presence of sufficient fructose and fat, demonstrating that the mechanism of voglibose could be effective in treating HFHFr diet-induced NAFLD. These results indicate that voglibose improves HFHFr diet-induced NAFLD by suppressing hepatic de novo lipogenesis.

Tandem mass tag-based proteomics analysis of type 2 diabetes mellitus with non-alcoholic fatty liver disease in mice treated with acupuncture

OBJECTIVE

To explore the proteomics profiles of hepatocytes of mice treated with acupuncture for type 2 diabetes mellitus (T2DM) with non-alcoholic fatty liver disease (NAFLD).

METHODS

We used a Tandem mass tag (TMT)-based quantitative proteomics approach to identify proteins with potential molecular mechanisms associated with acupuncture interventions for T2DM with NAFLD.

RESULTS

Acupuncture effectively improved body weight, blood glucose, and insulin levels in T2DM with NAFLD mouse models and reversed steatosis within hepatocytes. Quantitative TMT-based proteomics analysis identified a total of 4710 quantifiable proteins and 1226 differentially expressed proteins (DEPs) in the model control group (MCG) compared with the normal control group (NCG). The Acupuncture Treatment Group (ATG) presented in 122 DEPs was compared with the MCG group. We performed a bioinformatics analysis, which revealed that DEPs enriched in the KEGG pathway after acupuncture treatment were mainly involved in the PPAR signaling pathway, fatty acid biosynthesis, fatty acid metabolism, fatty acid elongation, fat digestion and absorption. We used parallel reaction monitoring (PRM) technology to explore the association of aldehyde oxidase 1 (Aox1), acyl-coenzyme A thioesterase 2 (Acot2), perilipin-2 (Plin2), acetyl-CoA carboxylase 1 (Acc), NADP-dependent malic enzyme (Me1), fatty acid synthase (Fasn), ATP-citrate synthase (Acly), fatty acid-binding protein, intestinal (Fabp2) with lipid synthesis, fatty acid oxidation, and hepatocyte steatosis.

CONCLUSIONS

Our results show that acupuncture can regulate the protein expression of T2DM in the NAFLD mice model, and can effectively improve hepatocyte steatosis, and has potential benefits for the clinical treatment of this disease.

Pharmacotherapy for Non-Alcoholic Fatty Liver Disease: Emerging Targets and Drug Candidates

Non-alcoholic fatty liver disease (NAFLD), or metabolic (dysfunction)-associated fatty liver disease (MAFLD), is characterized by high global incidence and prevalence, a tight association with common metabolic comorbidities, and a substantial risk of progression and associated mortality. Despite the increasingly high medical and socioeconomic burden of NAFLD, the lack of approved pharmacotherapy regimens remains an unsolved issue. In this paper, we aimed to provide an update on the rapidly changing therapeutic landscape and highlight the major novel approaches to the treatment of this disease. In addition to describing the biomolecules and pathways identified as upcoming pharmacological targets for NAFLD, we reviewed the current status of drug discovery and development pipeline with a special focus on recent evidence from clinical trials.

Nonalcoholic fatty liver disease (NAFLD) from pathogenesis to treatment concepts in humans

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) comprises hepatic alterations with increased lipid accumulation (steatosis) without or with inflammation (nonalcoholic steatohepatitis, NASH) and/or fibrosis in the absence of other causes of liver disease. NAFLD is developing as a burgeoning health challenge, mainly due to the worldwide obesity and diabetes epidemics.

SCOPE OF REVIEW

This review summarizes the knowledge on the pathogenesis underlying NAFLD by focusing on studies in humans and on hypercaloric nutrition, including effects of saturated fat and fructose, as well as adipose tissue dysfunction, leading to hepatic lipotoxicity, abnormal mitochondrial function, and oxidative stress, and highlights intestinal dysbiosis. These mechanisms are discussed in the context of current treatments targeting metabolic pathways and the results of related clinical trials.

MAJOR CONCLUSIONS

Recent studies have provided evidence that certain conditions, for example, the severe insulin-resistant diabetes (SIRD) subgroup (cluster) and the presence of an increasing number of gene variants, seem to predispose for excessive risk of NAFLD and its accelerated progression. Recent clinical trials have been frequently unsuccessful in halting or preventing NAFLD progression, perhaps partly due to including unselected cohorts in later stages of NAFLD. On the basis of this literature review, this study proposed screening in individuals with the highest genetic or acquired risk of disease progression, for example, the SIRD subgroup, and developing treatment concepts targeting the earliest pathophysiolgical alterations, namely, adipocyte dysfunction and insulin resistance.

Cellular protein markers, therapeutics, and drug delivery strategies in the treatment of diabetes-associated liver fibrosis

Liver fibrosis is the excessive accumulation of extracellular matrix due to chronic injuries, such as viral infection, alcohol abuse, high-fat diet, and toxins. Liver fibrosis is reversible before it progresses to cirrhosis and hepatocellular carcinoma. Type 2 diabetes significantly increases the risk of developing various complications including liver diseases. Abundant evidence suggests that type 2 diabetes and liver diseases are bidirectionally associated. Patients with type 2 diabetes experience more severe symptoms and accelerated progression of live diseases. Obesity and insulin resistance resulting from hyperlipidemia and hyperglycemia are regarded as the two major risk factors that link type 2 diabetes and liver fibrosis. This review summarizes possible mechanisms of the association between type 2 diabetes and liver fibrosis. The cellular protein markers that can be used for diagnosis and therapy of type 2 diabetes-associated liver fibrosis are discussed. We also highlight the potential therapeutic agents and their delivery systems that have been investigated for type 2 diabetes-associated liver fibrosis.

Acupuncture for type 2 diabetes mellitus with nonalcoholic fatty liver disease: A protocol for systematic review and meta-analysis

BACKGROUND

T2DM with NAFLD is a common disorder of glucose and lipid metabolism affecting the quality of life of patients. Due to the limitations and adverse reactions of drug treatment, acupuncture has been proved to be an effective method for the treatment of T2DM with NAFLD. This study aims to evaluate the efficacy and safety of acupuncture in the treatment of NAFLD in T2DM class, and to provide high-quality evidence for acupuncture in the treatment of this disease.

METHODS

From establishment of the database to 31 July 2021, We will search the Cochrane Central Register of controlled trials, PubMed, MEDLINE, EMBASE, Web of science. Five Chinese databases, including China National Knowledge Infrastructure (CNKI), WanFang database, VIP, Chinese Biomedical Literature Database (CBM) and the Chinese clinical trial registry. There are no restrictions on language or publication, and they are independently screened and collected by two reviewers. Review Manager 5.3 software will be used for meta analysis. If necessary, heterogeneity testing, data synthesis, and subgroup analysis will be performed.

RESULTS

The effectiveness and safety of acupuncture in the treatment of T2DM with NAFLD will be assessed by the outcomes of test's, including: imaging indicators, biomarkers of hepatic steatosis, serological indicators of hepatic fibrosis, improvement of serum NAFLD liver fat score, BMI, blood glucose indexes, blood lipid indexes, insulin level and safety indicators.

CONCLUSION

This meta-analysis will further determine the beneficial efficacy and safety of acupuncture for T2DM combined with NAFLD.

1-Deoxynojirimycin and its Derivatives: A Mini Review of the Literature

1-Deoxynojirimycin (1-DNJ) is a naturally occurring sugar analogue with unique bioactivities. It is found in mulberry leaves and silkworms, as well as in the metabolites of certain microorganisms, including Streptomyces and Bacillus. 1-DNJ is a potent α-glucosidase inhibitor and it possesses anti-hyperglycemic, anti-obese, anti-viral and anti-tumor properties. Some derivatives of 1-DNJ, like miglitol, miglustat and migalastat, were applied clinically to treat diseases such as diabetes and lysosomal storage disorders. The present review focused on the extraction, determination, pharmacokinetics and bioactivity of 1-DNJ, as well as the clinical application of 1-DNJ derivatives.

Clinical implications, diagnosis, and management of diabetes in patients with chronic liver diseases

Diabetes mellitus (DM) negatively affects the development and progression of chronic liver diseases (CLD) of various etiologies. Concurrent DM and CLD are also associated with worse clinical outcomes with respect to mortality, the occurrence of hepatic decompensation, and the development of hepatocellular carcinoma (HCC). Unfortunately, early diagnosis and optimal treatment of DM can be challenging, due to the lack of established clinical guidelines as well as the medical complexity of this patient population. We conducted an exploratory review of relevant literature to provide an up-to-date review for internists and hepatologists caring for this patient population. We reviewed the epidemiological and pathophysiological associations between DM and CLD, the impact of insulin resistance on the progression and manifestations of CLD, the pathogenesis of hepatogenic diabetes, as well as the practical challenges in diagnosis and monitoring of DM in this patient population. We also reviewed the latest clinical evidence on various pharmacological antihyperglycemic therapies with an emphasis on liver disease-related clinical outcomes. Finally, we proposed an algorithm for managing DM in patients with CLD and discussed the clinical and research questions that remain to be addressed.

Beneficial effect of anti-diabetic drugs for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder and is associated with various metabolic diseases, including type 2 diabetes mellitus. There are no approved drugs for NAFLD, and the only approved treatment option is weight reduction. As insulin resistance plays an important role in the development of NAFLD, many anti-diabetic drugs have been evaluated for the treatment of NAFLD. Improvement of liver enzymes has been demonstrated by many anti-diabetic drugs, but histological assessment still remains insufficient. Pioglitazone could become the first-line therapy for T2DM patients with NAFLD, based on evidence of histological improvement in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liraglutide, another promising alternative, is not yet recommended in patients with NAFLD/NASH due to limited evidence. Therefore, well-designed randomized controlled trials should be performed in the near future to demonstrate if and how anti-diabetic drugs can play a role in the treatment of NAFLD.

Long-term luseogliflozin therapy improves histological activity of non-alcoholic steatohepatitis accompanied by type 2 diabetes mellitus

A 60-year-old Japanese woman was referred to our hospital for further examination of persistent liver dysfunction. She had been suffering from type 2 diabetes mellitus since the age of 50 years. Her hemoglobin A1c (HbA1c) value was as high as 7.8% despite treatment with dipeptidyl peptidase-4 inhibitor, metformin, and sulfonylurea. After excluding viral hepatitis, alcohol or drug-induced liver injury, and autoimmune liver diseases, liver histology evidence of macrovesicular steatosis, hepatocyte ballooning, and pericellular fibrosis confirmed a diagnosis of non-alcoholic steatohepatitis (NASH). Luseogliflozin (2.5 mg/day), a sodium-glucose cotransporter 2 inhibitor (SGLT2I), was co-administered to strengthen glycemic control. Liver enzymes and HbA1c gradually improved without any adverse events. A second liver biopsy at 15 months after luseogliflozin commencement revealed improvements in steatosis, fibrosis, and overall histological activity score. This case demonstrates that long-term luseogliflozin may be a good therapeutic option for diabetic NAFLD/NASH patients. The merits of persistent SGLT2I administration for NAFLD/NASH patients warrant validation in future studies.

Current status, problems, and perspectives of non-alcoholic fatty liver disease research

Non-alcoholic fatty liver disease (NAFLD) is a major chronic liver disease that can lead to liver cirrhosis, liver cancer, and ultimately death. NAFLD is pathologically classified as non-alcoholic fatty liver (NAFL) or non-alcoholic steatohepatitis (NASH) based on the existence of ballooned hepatocytes, although the states have been known to transform into each other. Moreover, since the detection of ballooned hepatocytes may be difficult with limited biopsied specimens, its clinical significance needs reconsideration. Repeated liver biopsy to assess histological NAFLD activity for therapeutic response is also impractical, creating the need for body fluid biomarkers and less invasive imaging modalities. Recent longitudinal observational studies have emphasized the importance of advanced fibrosis as a determinant of NAFLD outcome. Thus, identifying predictors of fibrosis progression and developing better screening methods will enable clinicians to isolate high-risk NAFLD patients requiring early intensive intervention. Despite the considerable heterogeneity of NAFLD with regard to underlying disease, patient age, and fibrosis stage, several clinical trials are underway to develop a first-in-class drug. In this review, we summarize the present status and future direction of NAFLD/NASH research towards solving unmet medical needs.