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Aim: Following the coronavirus disease outbreak, a state of public emergency was declared worldwide, which enforced lifestyle changes. This study therefore aimed to investigate the changes in lifestyle, body composition, hepatic steatosis, and fibrosis in patients with chronic liver disease (CLD) under lockdown. Methods: During the lockdown period, 1344 patients with CLD answered a lifestyle questionnaire. In 298 patients, body composition and liver stiffness measure (LSM)/controlled attenuation parameter (CAP) were analyzed by InBody and FibroScan, respectively, and serial data were obtained in 137 patients. Results: More than half of the CLD patients answered decreases in physical activity and frequency of outings during lockdown, while diet was less affected. Overall, 58% of patients showed elevations in CAP values, which were not different statistically over time. Women, but not men, were more likely to increase CAP values during lockdown. Neither LSM nor serum fibrosis markers were elevated chronologically during lockdown. In men, body mass index (BMI), body fat percentage, and visceral fat area (VFA) were significantly increased, whereas in women, lower‐limb muscle mass was significantly decreased. Patients with decreased SMI showed elevations in CAP and VFA values, and patients who exercised less showed increases in BMI. Conclusion: In response to lockdown, men tended to increase body fat but the degree of hepatic steatosis was less affected, while women were more likely to exacerbate hepatic steatosis with skeletal muscle loss among CLD patients. Gender‐specific approaches need to be established for management of CLD patients to avoid exacerbation or comorbidity of steatotic liver disease. [ABSTRACT FROM AUTHOR]

Aim: Hepatic inclusion composed of autophagy‐specific substrate p62 is one of the histological features of non‐alcoholic fatty liver disease (NAFLD) and can be a precursor to hepatic carcinogenesis. The expression of p62 was enhanced by not only autophagic dysfunction but also oxidative stress and inflammation. M1/M2 phenotypic balance of macrophages plays a pivotal role in the progression of NAFLD. We evaluated the correlation between macrophage polarization and the formation of p62 aggregation in NAFLD. Methods: Liver biopsy specimens from NAFLD patients were analyzed by immunohistochemical staining for M1 macrophage marker CD11c, M2 macrophage marker CD163, and p62/SQSTM1 (p62). The histological severity of NAFLD is assessed by a NAFLD activity score (NAS). The number of autophagic vesicles in hepatocytes was visualized and counted by using transmission electron microscopy. Results: The aggregation of p62 was undetectable in control, whereas hepatocytes with p62 aggregation were observed in approximately 88% of NAFLD specimens. The number of hepatocytes with p62 aggregation was positively correlated with the number of autophagic vesicles, serum alanine aminotransferase, NAS, fibrosis, and the number of CD11c‐positive cells, but not CD163‐positive cells. Assembly of CD11c‐positive cells was observed around hepatocytes with p62 aggregation. The ratio of CD11c/CD163‐positive macrophages was significantly associated with the formation of p62 aggregation. Conclusions: These findings indicate that chronic inflammation by M1‐polarization of macrophages contributes to the disease progression from simple steatosis to non‐alcoholic steatohepatitis in concert with autophagic dysfunction. [ABSTRACT FROM AUTHOR]

Aim Pharmacological treatment for metabolic syndrome-related non-alcoholic steatohepatitis has not been established. We investigated the effect of L-carnitine, an essential substance for β-oxidation, on metabolic steatohepatitis in mice. Methods Male KK-Ay mice were fed a high-fat diet (HFD) for 8 weeks, with supplementation of L-carnitine (1.25 mg/mL) in drinking water for the latter 4 weeks. Results Serum total carnitine levels were decreased following HFD feeding, whereas the levels were reversed almost completely by L-carnitine supplementation. In mice given L-carnitine, exacerbation of hepatic steatosis and hepatocyte apoptosis was markedly prevented even though HFD feeding was continued. Body weight gain, as well as hyperlipidemia, hyperglycemia, and hyperinsulinemia, following HFD feeding were also significantly prevented in mice given L-carnitine. High-fat diet feeding elevated hepatic expression levels of carnitine palmitoyltransferase 1A mRNA; however, production of β-hydroxybutyrate in the liver was not affected by HFD alone. In contrast, L-carnitine treatment significantly increased hepatic β-hydroxybutyrate contents in HFD-fed mice. L-carnitine also blunted HFD induction in sterol regulatory element binding protein-1c mRNA in the liver. Furthermore, L-carnitine inhibited HFD-induced serine phosphorylation of insulin receptor substrate-1 in the liver. L-carnitine decreased hepatic free fatty acid content in 1 week, with morphological improvement of swollen mitochondria in hepatocytes, and increases in hepatic adenosine 5'-triphosphate content. Conclusions L-carnitine ameliorates steatohepatitis in KK-Ay mice fed an HFD, most likely through facilitating mitochondrial β-oxidation, normalizing insulin signals, and inhibiting de novo lipogenesis in the liver. It is therefore postulated that supplementation of L-carnitine is a promising approach for prevention and treatment of metabolic syndrome-related non-alcoholic steatohepatitis. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the role of natural killer (NK)T cells in the pathogenesis of non-alcoholic steatohepatitis (NASH), here we investigated the expression and function of hepatic NKT cells in KK-Ay mice, an animal model of metabolic syndrome. Methods: Male, 8-week-old KK-Ay and C57Bl/6 mice were fed a high-fat (HF) diet for 4 weeks. Some mice were given daily intragastric injections of pioglitazone for 5 days prior to or after dietary treatment. Results: In untreated KK-Ay mice, the percentages of NKT cells in liver mononucleolar cells were nearly one-third of those in C57Bl/6 controls. Elevations in interleukin (IL)-4 and interferon (IFN)-γ mRNA in the liver after a single injection of α-galactosylceramide (GalCer) were blunted in KK-Ay mice largely. Percentages of NKT cells, as well as GalCer-induced increases in IL-4 mRNA, were blunted significantly in both strains after HF diet feeding for 4 weeks. Interestingly, KK-Ay mice pretreated with pioglitazone showed significant increases in NKT cell proportion, and GalCer-induced increases in IL-4 and IFN-γ mRNA were also enhanced by pioglitazone. In KK-Ay mice, the percentages of annexin V positive NKT cells were nearly 2.5-fold higher than those in C57Bl/6 controls; however, pioglitazone decreased annexin V positive cells significantly. Moreover, pioglitazone increased NKT cell fraction in KK-Ay mice even after HF diet feeding. Conclusion: KK-Ay mice exhibit proportional and functional alterations in hepatic NKT cells in close relation with the development of steatohepatitis, and it is postulated that pioglitazone improves steatohepatitis in part through restoration of hepatic NKT cells. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated a dietary model of steatohepatitis caused by methionine- and choline-deficiency (MCD) in obese, diabetic KK–Ay mice. Male KK–Ay mice and C57Bl/6 mice were fed an MCD diet for up to 8 weeks, and liver pathology was evaluated. Hepatic steatosis and inflammatory infiltration were more prominent in KK–Ay mice than in C57Bl/6 mice 4 weeks after feeding with MCD diet. MCD diet-induced increases in tumor necrosis factor (TNF)-α mRNA levels, as well as lipid peroxidation, in the liver were also potentiated significantly in KK–Ay mice. Extended degree of hepatic fibrosis was observed in KK–Ay mice as compared to C57Bl/6 mice 8 weeks after feeding with MCD diet. Indeed, α1(I)procollagen and transforming growth factor (TGF)-β1 mRNA levels were significantly higher in KK–Ay mice following dietary treatment. Serum adiponectin levels were elevated nearly two-fold when C57Bl/6 mice were given MCD diet for 4 weeks; however, serum adiponectin levels in KK–Ay mice fed both the control- and MCD diet were the same, reaching the values almost 1/2 of those in C57Bl/6 mice. In conclusion, KK–Ay mice exhibit increased susceptibility to MCD diet-induced steatohepatitis, where hypoadiponectinemia most likely plays a key role in exacerbation of both inflammatory and profibrogenic responses. [Copyright &y& Elsevier]