Ginkgetin exhibits antifibrotic effects by inducing hepatic stellate cell apoptosis via STAT1 activation

Association between overt hepatic encephalopathy and liver pathology after transjugular intrahepatic portosystemic shunt creation in cirrhotic patients

To investigate the association between overt hepatic encephalopathy (OHE) and liver pathology after transjugular intrahepatic portosystemic shunt (TIPS) creation in cirrhotic patients. From July 2015 to April 2024, 73 patients from 4 hospitals in China who received TIPS creation and liver biopsy were retrospectively enrolled in this study. Based on whether OHE occurred within 3 months after TIPS creation, the patients were categorized into OHE (n = 29) and non-OHE (n = 44) groups. The liver pathology was assessed by hematoxylin-eosin (H&E), Sirius red staining, immunohistochemistry, and immunofluorescence. Liver pathology by H&E staining showed typical features of liver cirrhosis (including disordered structure and pseudolobule formation) in all the patients. No marked difference was observed in extracellular matrix (ECM) deposition between the OHE and non-OHE groups. However, the patients in the OHE group had a higher level of liver and systemic inflammation than in the non-OHE group. And there was a strong correction between intrahepatic macrophage infiltration and serum inflammatory indicators. Additionally, the OHE group had more liver neovascularization, which was consistent with liver inflammation. The emergence of OHE after TIPS creation is closely associated with liver pathology, especially in liver inflammation and angiogenesis, but not in ECM deposition.

Hepcidin inhibits hepatocyte apoptosis through the PERK pathway in acute liver injury and fibrosis

BACKGROUND

Hepcidin, a peptide hormone primarily produced by the liver, regulates iron metabolism by interacting with its receptor, ferroportin. Studies have demonstrated that hepcidin participates in the progression of liver fibrosis by regulating HSC activation, but its regulatory effect on hepatocytes remains largely unknown.

METHODS

A carbon tetrachloride (CCl4)-induced liver fibrosis model was established in C57BL/6 wild-type (WT) and hepcidin knockout (Hamp-/-) mice. Liver injury and inflammation were assessed in WT and Hamp-/- mice at 24 and 48 hours following acute CCl4 exposure. In addition, transcriptomic sequencing of primary hepatocytes was performed to compare gene expression profiles between WT and Hamp-/- mice 24 hours after liver injury. The function of the identified molecule Eif2ak3/PERK (protein kinase R(PKR)-like endoplasmic reticulum kinase), was evaluated both in vitro and in vivo.

RESULTS

We found that serum hepcidin significantly increased during the progression of liver fibrosis induced by CCl4 and bile duct ligation. In addition, CCl4-treated Hamp-/- mice developed more severe liver injury, liver fibrosis, and hepatocyte apoptosis, with elevated Bax and decreased Bcl-2 expression, compared to the WT mice. Transcriptomic analysis of primary hepatocytes revealed that PERK was upregulated in Hamp-/- mice after CCl4 treatment, promoting apoptosis by regulating Bax and Bcl-2 expression. Subsequently, we demonstrated that hepcidin prevents hepatocyte apoptosis by inhibiting PERK both in vitro and in vivo.

CONCLUSIONS

Hepcidin inhibits hepatocyte apoptosis through suppression of the PERK pathway, highlighting its protective role in liver fibrosis and identifying a potential therapeutic target for the treatment of liver fibrosis.

Evaluation of Aortic Hemodynamics Using Four-Dimensional Flow of Magnetic Resonance Imaging in Rabbits with Liver Fibrosis

BACKGROUND

Liver fibrosis (LF) precipitates systemic hemodynamic alterations, however, its impact on the aorta remaining undefined.

PURPOSE

To assess aorta hemodynamics changes during LF development in a rabbit model.

STUDY TYPE

Prospective, experimental.

ANIMAL MODEL

Thirty 7-month-old male rabbits underwent bile duct ligation (BDL) to induce LF.

FIELD STRENGTH/SEQUENCE

Biweekly four-dimensional (4D) flow imaging incorporating a 3D gradient-echo at 3.0 T scanner for 14 weeks post-BDL.

ASSESSMENT

Histopathological exams for 2-5 rabbits were performed at each time point, following each MRI scan. LF was graded using the Metavir scale by a pathologist. 4D flow was analyzed by two radiologists using dedicated postprocessing software. They recorded 4D flow parameters at four aorta sections (aortic sinus, before and after bifurcation of aortic arch, and descending aorta).

STATISTICAL TESTS

The linear mixed model; Bonferroni correction; Pearson correlation coefficient (r); receiver operating characteristic (ROC) curve; Delong test. The level of significance was set at P < 0.05.

RESULTS

Following BDL, the wall shear stress (WSS) (0.23-0.32 Pa), energy loss (EL) (0.27-1.55 mW) of aorta significantly increased at the second week for each plane, peaking at the sixth week (WSS: 0.35-0.49 Pa, EL: 0.57-2.0 mW). So did the relative pressure difference (RPD) (second week: 1.67 ± 1.63 mmHg, sixth week: 2.43 ± 0.63 mmHg) in plane 2. Notably, the RPD in plane 2 at the second week displayed the highest area under ROC curve of 0.998 (specificity: 1, sensitivity: 0.967). LF were found at the second, fourth, and sixth week after BDL, with grade F2, F3, and F4, respectively. The RPD in plane 2 was most strongly correlated with the severity of LF (r = 0.86).

DATA CONCLUSIONS

The occurrence of LF could increase WSS, EL, and RPD of aorta as early as the second week following BDL.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 2.

Bidirectional Impact of Varying Severity of Acute Kidney Injury on Calcium Oxalate Stone Formation

INTRODUCTION

Acute kidney injury (AKI) is a prevalent renal disorder. The occurrence of AKI may promote the formation of renal calcium oxalate stones by exerting continuous effects on renal tubular epithelial cells (TECs). We aimed to delineate the molecular interplay between AKI and nephrolithiasis.

METHODS

A mild (20 min) and severe (30 min) renal ischemia-reperfusion injury model was established in mice. Seven days after injury, calcium oxalate stones were induced using glyoxylate (Gly) to evaluate the impact of AKI on the formation of kidney stones. Transcriptome sequencing was performed on TECs to elucidate the relationship between AKI severity and kidney stones. Key transcription factors (TFs) regulating differential gene transcription levels were identified using motif analysis, and pioglitazone, ginkgetin, and fludarabine were used for targeted therapy to validate key TFs as potential targets for kidney stone treatment.

RESULTS

Severe AKI led to increased deposition of calcium oxalate crystals in renal, impaired kidney function, and upregulation of kidney stone-related gene expression. In contrast, mild AKI was associated with decreased crystal deposition, preserved kidney function, and downregulation of similar gene expression. Transcriptomic analysis revealed that genes associated with inflammation and cell adhesion pathways were significantly upregulated after severe AKI, while genes related to energy metabolism pathways were significantly upregulated after mild AKI. An integrative bioinformatic analysis uncovered a TF regulatory network within TECs, pinpointing that PKNOX1 was involved in the upregulation of inflammation-related genes after severe AKI, and inhibiting PKNOX1 function with pioglitazone could simultaneously reduce the increase of calcium oxalate crystals after severe AKI in kidney. On the other hand, motif analysis also revealed the protective role of STAT1 in the kidneys after mild AKI, enhancing the function of STAT1 with ginkgetin could reduce kidney stone formation, while the specific inhibitor of STAT1, fludarabine, could eliminate the therapeutic effects of mild AKI on kidney stones.

CONCLUSION

Inadequate repair of TECs after severe AKI increases the risk of kidney stone formation, with the upregulation of inflammation-related genes regulated by PKNOX1 playing a role in this process. Inhibiting PKNOX1 function can reduce kidney stone formation. Conversely, after mild AKI, effective cell repair through upregulation of STAT1 expression can protect TEC function and reduce stone formation, and activating STAT1 function can also achieve the goal of treating kidney stones.