Background: It has been documented that Helicobacter hepaticus (H hepaticus) infection is linked to chronic hepatitis and liver cancer. However, our understanding of the molecular mechanisms underlying progression of the H hepaticus‐induced hepatic inflammation to cellular hepatocarcinoma is still limited.Materials and methods: In our study, male BALB/c mice were infected by H hepaticus for 8, 12, 16, 20, and 24 weeks. Histopathology, H hepaticus colonization dynamics, select signaling pathways, and expression of key inflammatory cytokines in the liver were examined.Results: We found that H hepaticus was detectible in feces of mice at 7 days postinfection (DPI) by PCR, but it was not detected in the livers by PCR until 8 weeks postinfection (WPI). In addition, abundance of colonic and hepatic H hepaticus was progressively increased over the infection duration. H hepaticus‐induced hepatic inflammation and fibrosis were aggravated over the infection duration, and necrosis or cirrhosis developed in the infected liver at 24 WPI H hepaticus infection increased levels of alanine aminotransferase and aspartate aminotransferase. Moreover, mRNA levels of Il‐6 and Tnf‐α were significantly elevated in the livers of H hepaticus‐infected mice compared to uninfected control from 8 WPI to 24 WPI. Furthermore, Stat3, nuclear factor‐κB (p65), and MAPK (Erk1/2 and p38) were activated by H hepaticus infection.Conclusions: These data demonstrated that male BALB/c mice can be used as a new mouse model of H hepaticus‐induced liver diseases and that the H hepaticus‐induced liver injury is triggered by NF‐κB, Jak‐Stat, and MAPK signaling pathways.

Autophagy is a homoeostatic process by which cytoplasmic material is targeted for degradation by the cell. Viruses have learned to manipulate the autophagic pathway to ensure their own replication and survival. Although much progress has been achieved in dissecting the interplay between viruses and cellular autophagic machinery, it is not well understood how the cellular autophagic pathway is utilized by viruses and manipulated to their own advantage. In this review, we briefly introduce autophagy, viral xenophagy and the interaction among autophagy, virus and immune response, then focus on the interplay between NS-RNA viruses and autophagy during virus infection. We have selected some exemplary NS-RNA viruses and will describe how these NS-RNA viruses regulate autophagy and the role of autophagy in NS-RNA viral replication and in immune responses to virus infection. We also review recent advances in understanding how NS-RNA viral proteins perturb autophagy and how autophagy-related proteins contribute to NS-RNA virus replication, pathogenesis and antiviral immunity.

Deficiency of glycogen branching enzyme (GBE) causes glycogen storage disease type IV (GSD IV), which is characterized by the accumulation of a less branched, poorly soluble form of glycogen called polyglucosan (PG) in multiple tissues. We evaluate the efficacy of gene therapy with an adeno-associated viral (AAV) vector in a mouse model of adult form of GSD IV (Gbe1ys/ys). An AAV serotype 9 (AAV9) vector containing a human GBE expression cassette (AAV-GBE) was intravenously injected into 14-day-old Gbe1ys/ys mice at a dose of 5x1011 vector genomes per mouse. Mice were euthanized at 3 and 9 months of age. In the AAV-treated mice at age of 3 months, GBE enzyme activity was highly elevated in heart, which is consistent with the high copy number of the viral vector genome detected. GBE activity also increased significantly in skeletal muscles and the brain, but not in liver. Glycogen contents were reduced to wild-type levels in muscles and significantly reduced in liver and brain. At 9 months of age, though GBE activity was only significantly elevated in heart, glycogen levels were significantly reduced in liver, brain, and skeletal muscles of the AAV-treated mice. In addition, the AAV treatment resulted in an overall decrease in plasma activities of alanine transaminase, aspartate transaminase, and creatine kinase, and a significant increase in fasting plasma glucose concentration at age of 9 months. This suggests an alleviation of damage and improvement of function in liver and muscle by the AAV treatment. This study demonstrated a long-term benefit of a systemic injection of an AAV-GBE vector in the Gbe1ys/ys mice.

Host-pathogen interaction influences many non-infectious diseases, including metabolic diseases. Helicobacter hepaticus (H. hepaticus) has been found in some metabolic dysfunction-associated steatotic liver disease (MASLD) patients, however, the causal link and underlying mechanisms remain unclear. Here we report that H. hepaticus infection or overexpression of CdtB of H. hepaticus induces lipid deposition in hepatocytes, both in vivo and in vitro. Furthermore, we identify that CdtB translocates to mitochondria with the help of Hsp90, interacts with ATP5A1, reduces mitochondrial respiratory complex V activity, damages mitochondria, and disrupts lipid metabolism. Mechanistically, CdtB-induced lipogenesis depends on the CdtB-mitochondrial ROS-mTORC1-SREBP1 axis and CdtB-mediated NONO expression to enhance nuclear localization of SREBP1 that promote the de novo fatty acid synthesis in the hepatocytes. Neutralization of CdtB significantly alleviates hepatic lipidosis in mice upon H. hepaticus infection. Furthermore, the nucleic acid of H. hepaticus has been detected in the liver tissues of some patients with MASLD, which suggests a certain correlation between liver infection with H. hepaticus and the occurrence and progression of MASLD. Our findings highlight the critical role of CdtB in the pathogenesis of H. hepaticus infection-induced hepatic lipidosis and its potential as a therapeutic target.