Potential effects of adropin on systemic metabolic and hormonal abnormalities in polycystic ovary syndrome

Hepatokines: the missing link in the development of insulin resistance and hyperandrogenism in PCOS?

The liver plays a critical role in several metabolic pathways, including the regulation of glucose and lipid metabolism. Non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease worldwide, is closely associated with insulin resistance (IR) and metabolic syndrome (MetS). Hepatokines, newly discovered proteins secreted by hepatocytes, have been linked to the induction of these metabolic dysregulations. Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, has been associated with NAFLD and IR, while hyperandrogenism additionally appears to be implicated in the pathogenesis of the latter. However, the potential role of hepatokines in the development of metabolic disorders in PCOS has not been fully investigated. Therefore, the aim of this review is to critically appraise the current evidence regarding the interplay of hepatokines with NAFLD, hyperandrogenism, and IR in PCOS.

Low-dose adropin stimulates inflammasome activation of macrophage via mitochondrial ROS involved in colorectal cancer progression

Adropin is encoded by the energy homeostasis-associated (ENHO) gene and widely present in liver, pancreas, heart, kidney, brain, and vascular tissues. Abnormal adropin is associated with metabolic, inflammatory, immune, and central nervous disorders. Whether adropin is involved in the development of colorectal cancer (CRC) is still unclear. Here, decreased adropin expression of tumor-nest cells in advanced-stage CRC was demonstrated. Adropin expressed by carcinoma cells was negatively correlated with macrophage infiltration in the matrix of CRC tissues. However, tumor macrophages enhanced adropin expression and were positively correlated with tumor invasion and metastasis. ENHO gene transfection into colon cancer (MC38) cells inhibited tumor growth in vivo, accompanying the increase of M1 macrophages. Treatment with low-dose adropin (< 100 ng/mL) on macrophages ex vivo directly increased mitochondrial reactive oxygen species for inflammasome activation. Furthermore, ENHO-/- mice had less M1 macrophages in vivo, and ENHO-/- macrophages were inert to be induced into the M1 subset ex vivo. Finally, low-dose adropin promoted glucose utilization, and high-dose adropin enhanced the expression of CPT1α in macrophages. Therefore, variations of adropin level in carcinoma cells or macrophages in tumor tissues are differently involved in CRC progression. Low-dose adropin stimulates the antitumor activity of macrophages, but high-dose adropin facilitates the pro-tumor activity of macrophages. Increasing or decreasing the adropin level can inhibit tumor progression at different CRC stages.

From NAFLD to HCC: Advances in noninvasive diagnosis

Non-alcoholic fatty liver disease (NAFLD) has gradually become one of the major liver health problems in the world. The dynamic course of the disease goes through steatosis, inflammation, fibrosis, and carcinoma. Before progressing to carcinoma, timely and effective intervention will make the condition better, which highlights the importance of early diagnosis. With the further study of the biological mechanism in the pathogenesis and progression of NAFLD, some potential biomarkers have been discovered, and the possibility of their clinical application is gradually being discussed. At the same time, the progress of imaging technology and the emergence of new materials and methods also provide more possibilities for the diagnosis of NAFLD. This article reviews the diagnostic markers and advanced diagnostic methods of NAFLD in recent years.

Longitudinal changes in serum adropin levels and liver fat content during liraglutide treatment in newly diagnosed patients with type 2 diabetes mellitus and metabolic dysfunction-associated fatty liver disease

AIMS

To explore the effect of liraglutide treatment on serum adropin and its relationship to the liver fat content in newly diagnosed patients with type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated fatty liver disease (MAFLD).

METHODS

Serum adropin level and liver fat content were assessed in patients with T2DM and MAFLD (n = 22), along with healthy controls (n = 22). Afterward, the patients received liraglutide treatment for 12 weeks. Serum adropin levels were examined by a competitive enzyme-linked immunosorbent assay. Liver fat content was quantified via magnetic resonance imaging-estimated proton density fat fraction (MRI-PDFF).

RESULTS

We found that patients with newly diagnosed T2DM and MAFLD had lower serum adropin levels [2.79 ± 0.47 vs. 3.27 ± 0.79 ng/mL, P < 0.05] and higher liver fat content [19.12 ± 9.46 vs. 4.67 ± 0.61%, P < 0.001], compared to healthy controls. Following 12-week liraglutide treatment, serum adropin levels increased from 2.83(2.44, 3.24) to 3.65(3.20, 3.85) ng/mL (P < 0.001), and liver fat content decreased from 18.04(11.08, 27.65) to 7.74(6.42, 13.49) % (P < 0.001) in patients with T2DM and MAFLD. Furthermore, increases in serum adropin were strongly associated with decreases in liver fat content (β = - 5.933, P < 0.001), liver enzyme and glucolipid metabolism parameters.

CONCLUSION

The increase in serum adropin level following liraglutide treatment was strongly correlated with the reduction in liver fat content and glucolipid metabolism. Hence, adropin might be a potential marker for the beneficial effects of liraglutide on treating T2DM and MAFLD.

Differences in metabonomic profiles of abdominal subcutaneous adipose tissue in women with polycystic ovary syndrome

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that often coexists with a metabolic disorder. Studies have demonstrated that the malfunction of adipose tissue, particularly abdominal adipose tissue, could exacerbate reproductive and metabolic problems in PCOS patients. Adipose tissue-secreted signaling mediators (e.g., lipids and metabolites) would then interact with other body organs, including the ovary, to maintain the systemic equilibrium.

METHODS

In this study, we examined adipose samples from PCOS patients and unaffected individuals using a liquid chromatography-mass spectrometry-based metabonomics approach (LC-MS/MS). PCOS biomarkers were selected using multivariate statistical analysis.

RESULTS

Our pathway analysis revealed that these differential metabolites could be engaged in inflammatory diseases and mitochondrial beta-oxidation. We further developed an in vitro PCOS cell model to examine the effects of hyperandrogenism on granulosa cells and related metabolic disorders. We noted that isoleucine recovered the promotive effect on cell apoptosis, inhibitory effect on cell proliferation, sex hormone secretion, and mitochondrial function induced by dehydroepiandrosterone. Our gas chromatography-mass spectrometry targeted analysis (GC-MS/MS) revealed that isoleucine was significantly decreased in PCOS patients.

DISCUSSION

Based on these results, we speculate that metabolome alterations are vital in ameliorating PCOS symptoms. This may be a novel therapeutic target for PCOS treatment. Our study provides preliminary evidence that these findings will enhance our ability to accurately diagnose and intervene in PCOS.

Correlation Between Circulating Adropin Levels and Patients with PCOS: An Updated Systematic Review and Meta-analysis

An increasing number of young women suffer from polycystic ovary syndrome (PCOS). Reasonable diagnosis and monitoring are important steps in the treatment of PCOS. Therefore, we performed an updated meta-analysis between adropin levels and PCOS to identify their relationship. We searched 8 databases (Pubmed, EMBASE, Cochrane Library, CNKI, Wanfang, CBM, clinicaltrials.gov, OpenGrey) for relevant studies using the following search items: 'PCOS or polycystic ovary syndrome or Stein-Leventhal syndrome' AND 'adropin'. Standardized mean difference (SMD) and 95% confidence intervals(CIs) were used as the outcomes. Data were analyzed using Revman 5.3, Stata 16, and MetaXL. Nineteen articles were include in this meta-analysis. The PCOS group had significantly lower adropin levels than the healthy groups (SMD = -2.79 ng/ml, 95%CI (-3.42, -2.16), p < 0.00001). Significant publication bias (p < 0.05) was observed; additionally, the results were robust based on metatrim and fail-safe number (Nfs). Meta-regression analysis showed that age, glucose ratio and luteinizing hormone (LH) may be sources of heterogeneity (univariate meta-regression analysis: P = 0.058 vs P = 0.026 vs P = 0.091). Furthermore, BMI, insulin, glucose, HOMA-IR, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) may be closely related to adropin levels (p < 0.05) owing to meta-analysis of correlation coefficient. We found there was a correlation between adropin levels and PCOS: circulating adropin levels were significantly lower in patients with PCOS than healthy controls, which may be helpful for clinical diagnosis and detection of PCOS.

Adropin levels and its associations as a fat-burning hormone in patients with polycystic ovary syndrome: a correlational meta-analysis

AIMS

Adropin is a peptide hormone with potential implications in patients with polycystic ovary syndrome (PCOS). The aim of this meta-analysis was to compare the circulating (serum/plasma) and follicular fluid adropin levels between human PCOS patients and non-PCOS controls.

METHODS

Relevant studies were retrieved by online database and manual searching. The standardized mean differences (SMDs) with 95% confidence intervals (CIs) were obtained by a random-effects meta-analysis. Meta-analysis of correlations was performed for the associations of adropin with anthropometric, lipid, insulin resistance and hormonal covariates. The funnel plot analysis with Begg's and Egger's tests was used for publication bias.

RESULTS

A total of 9 studies were included in this meta-analysis. The results indicated that the adropin levels were significantly decreased in PCOS patients as compared to non-PCOS controls (SMD = -1.87, 95% CI = -2.55 to -1.18, p < .0001). This decrease was more evident in overweight PCOS patients than their normoweight counterparts (SMD = -0.55, 95% CI = -0.80 to -0.30, p < .0001). A one-study leave-out sensitivity analysis indicated that no single study had a significant influence on the overall outcome, suggesting the robustness of this meta-analysis. There were significant associations of decreased adropin levels with the body mass index, dyslipidemia and insulin resistance in PCOS.

CONCLUSION

Adropin levels are significantly reduced in PCOS patients compared to controls, and this decrease was more evident in overweight PCOS patients.

Serum Adropin as a Potential Biomarker for Predicting the Development of Type 2 Diabetes Mellitus in Individuals With Metabolic Dysfunction-Associated Fatty Liver Disease

Background: Adropin, a peptide translated from the Energy Homeostasis Associated gene (ENHO), was mainly expressed in the liver and was a regulator in metabolic and energy homeostasis. This study aims to investigate the correlation between adropin and histological characteristics of the liver, and the clinical relevance of adropin in patients with metabolic dysfunction-associated fatty liver disease (MAFLD).

Methods: A total of 62 subjects, including 32 healthy controls and 30 MAFLD patients, were enrolled in this case-control study. The MAFLD patients were further divided into two subgroups, including NGT-M group and T2DM-M group. Serum adropin levels, metabolic parameters and intrahepatic lipids, the liver ENHO mRNA expressions and histological characteristics were investigated.

Results: MAFLD patients showed significantly lower circulating adropin compared with healthy controls (2.02 ± 2.92 vs. 5.52 ± 0.65 ng/mL, P < 0.0001). Subgroup analysis exhibited dramatically declined serum adropin levels in T2DM-M patients compared with NGT-M group (0.51 ± 0.73 vs. 4.00 ± 3.52 ng/mL, P < 0.001). H&E and Oil Red O staining show exacerbated steatohepatitis in T2DM-M patients in contrast with NGT-M group. Furthermore, serum adropin concentrations were negatively correlated with intrahepatic triglyceride (TG), total cholesterol (TC), and NAFLD activity score (NAS) (TG: r = −0.495; TC: r = −0.392; NAS: r = −0.451; all P < 0.05).

Conclusions: MAFLD patients showed significantly lower adropin levels than the healthy controls, especially in T2DM patients. Adropin maybe a potential biomarker for predicting the development of MAFLD, especially in T2DM individuals.