The Role of Growth Hormone and Insulin Growth Factor 1 in the Development of Non-Alcoholic Steato-Hepatitis: A Systematic Review

Prolonged Cold Exposure Negatively Impacts Atlantic Salmon (Salmo salar) Liver Metabolism and Function

Large-scale mortality events have occurred during the winter in Atlantic salmon sea cages in Eastern Canada and Iceland. Thus, in salmon held at 3 °C that were apparently healthy (i.e., asymptomatic) and that had 'early' and 'advanced' symptoms of 'winter syndrome'/'winter disease' (WS/WD), we measured hepatic lipid classes and fatty acid levels, and the transcript expression of 34 molecular markers of fatty liver disease (FLD; a clinical sign of WS/WD). In addition, we correlated our results with previously reported characteristics associated with this disease's progression in these same individuals. Total lipid and triacylglycerol (TAG) levels increased by ~50%, and the expression of 32 of the 34 genes was dysregulated, in fish with symptoms of FLD. TAG was positively correlated with markers of inflammation (5loxa, saa5), hepatosomatic index (HSI), and plasma aspartate aminotransferase levels, but negatively correlated with genes related to lipid metabolism (elovl5b, fabp3a, cd36c), oxidative stress (catc), and growth (igf1). Multivariate analyses clearly showed that the three groups of fish were different, and that saa5 was the largest contributor to differences. Our results provide a number of biomarkers for FLD in salmon, and very strong evidence that prolonged cold exposure can trigger FLD in this ecologically and economically important species.

U-Shaped relationship of insulin-like growth factor I and incidence of nonalcoholic fatty liver in patients with pituitary neuroendocrine tumors: a cohort study

Context

Although the role of insulin-like growth factor I (IGF-1) in nonalcoholic fatty liver disease (NAFLD) has garnered attention in recent years, few studies have examined both reduced and elevated levels of IGF-1.

Objective

The aim of this study was to examine the potential relationship between IGF-1 levels and the risk of new-onset NAFLD in patients with pituitary neuroendocrine tumors (PitNET).

Methods

We employed multivariable Cox regression models and two-piecewise regression models to assess the association between IGF-1 and new-onset NAFLD. Hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated to quantify this association. Furthermore, a dose-response correlation between lgIGF-1 and the development of NAFLD was plotted. Additionally, we also performed subgroup analysis and a series sensitivity analysis.

Results

A total of 3,291 PitNET patients were enrolled in the present study, and the median duration of follow-up was 65 months. Patients with either reduced or elevated levels of IGF-1 at baseline were found to be at a higher risk of NAFLD compared to PitNET patients with normal IGF-1(log-rank test, P < 0.001). In the adjusted Cox regression analysis model (model IV), compared with participants with normal IGF-1, the HRs of those with elevated and reduced IGF-1 were 2.33 (95% CI 1.75, 3.11) and 2.2 (95% CI 1.78, 2.7). Furthermore, in non-adjusted or adjusted models, our study revealed a U-shaped relationship between lgIGF-1 and the risk of NAFLD. Moreover, the results from subgroup and sensitivity analyses were consistent with the main results.

Conclusions

There was a U-shaped trend between IGF-1 and new-onset NAFLD in patients with PitNET. Further evaluation of our discoveries is warranted.

LncRNA MIR22HG/microRNA-9-3p/IGF1 in nonalcoholic steatohepatitis, the ceRNA network increases fibrosis by inhibiting autophagy and promoting pyroptosis

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is known to progress due to the impact of long non-coding RNAs (lncRNAs), which have been linked to autophagy, pyroptosis, and fibrosis in NASH cells. However, the exact mechanisms underpinning these processes remain unclear. This study focuses on the role of lncRNA MIR22HG (MIR22HG) in NASH.

METHODS

The expression of differentially expressed lncRNA was analyzed by RNA sequencing. Mouse models of NASH induced by MCD and HFD were validated. The expression of MIR22HG in HFD and MCD mouse liver tissue samples, FFA cells constructed with HepG2 and Huh7, and human liver tissue samples were detected by QRT-PCR. In addition, We used RNA immunoprecipitation, luciferase reporting, miRNA transfection, plasmid construction, immunofluorescence, Western blot, qRT-PCR, ELISA, and hybridization techniques to elucidate the relationship between MIR22HG, microRNA-9-3p (miR-9-3p), and IGF1. In addition, the mechanism of MIR22HG and PTEN/AKT was explored by Western blot analysis.

RESULTS

RNA-seq found that 3751 mRNAs and 23 lncRNAs were differentially expressed, which constituted a lncRNA-miRNA-mRNA regulatory network. Studies demonstrated the downregulation of MIR22HG in HFD and MCD mouse liver tissue samples (p = 1.00E-04 and p = 4.6E-03). Our results showed that overexpression of MIR22HG promoted autophagy and inhibited pyroptosis and fibrosis through the miR-9-3p/IGF1 pathway, thus slowing the occurrence and development of NASH. Further, we observed a low expression of MIR22HG and IGF1, but a high expression of miR-9-3p in NASH patients, a finding in alignment with our in vivo and in vitro results.

CONCLUSION

Using MIR22HG as a biomarker and therapeutic target for NASH patients, we found that it plays a pivotal role in detecting autophagy, pyroptosis, and fibrosis through the ceRNA pathway.

The Role of mTOR Inhibitors after Liver Transplantation for Hepatocellular Carcinoma

Liver transplantation is a treatment option for nonresectable patients with early-stage HCC, with more significant advantages when Milan criteria are fulfilled. An immunosuppressive regimen is required to reduce the risk of graft rejection after transplantation, and CNIs represent the drugs of choice in this setting. However, their inhibitory effect on T-cell activity accounts for a higher risk of tumour regrowth. mTOR inhibitors (mTORi) have been introduced as an alternative immunosuppressive approach to conventional CNI-based regimens to address both immunosuppression and cancer control. The PI3K-AKT-mTOR signalling pathway regulates protein translation, cell growth, and metabolism, and the pathway is frequently deregulated in human tumours. Several studies have suggested the role of mTORi in reducing HCC progression after LT, accounting for a lower recurrence rate. Furthermore, mTOR immunosuppression controls the renal damage associated with CNI exposure. Conversion to mTOR inhibitors is associated with stabilizing and recovering renal dysfunction, suggesting an essential renoprotective effect. Limitations in this therapeutic approach are related to their negative impact on lipid and glucose metabolism as well as on proteinuria development and wound healing. This review aims to summarize the roles of mTORi in managing patients with HCC undergoing LT. Strategies to overcome common adverse effects are also proposed.