The Elk-3 target Abhd10 ameliorates hepatotoxic injury and fibrosis in alcoholic liver disease

Chaihuang Yishen Granule ameliorates mitochondrial homeostasis by upregulating PRDX5/TFAM axis to inhibit renal fibrosis in CKD

BACKGROUND

Chaihuang Yishen Granules (CHYS) has been clinically proven to be effective for the treatment of chronic kidney disease (CKD), yet its underlying molecular mechanisms remain largely unexplored.

OBJECTIVE

To explore the innovative mechanisms by which CHYS alleviates CKD, focusing on its role in modulating PRDX5/TFAM-mediated mitochondrial homeostasis in renal cells.

METHODS

In this study, CKD mouse model was established by unilateral ureteral obstruction (UUO) and adenine (Ade) diet. Treatment interventions were administered by gavage with CHYS at doses of 3.8g/kg (low dose) and 7.6g/kg (high dose). The ameliorative effects of CHYS on CKD were evaluated by changes in renal function, kidney tissue structure, renal fibrosis, and mitochondrial dysfunction markers. Tert‑butyl hydroperoxide (t-BHP)-induced oxidative stress in TCMK1 cells was used to simulate CKD renal fibrosis induced by mitochondrial dysfunction in vitro.

RESULTS

CHYS significantly improves renal function and mitigates fibrosis while restoring mitochondrial homeostasis. Notably, PRDX5 expression, which is markedly reduced in CKD patients and mouse models, is substantially upregulated following CHYS treatment. Meanwhile, we demonstrate that ultrasound microbubble-mediated in situ overexpression of PRDX5 confers considerable renal protection in the UUO model. In vitro data show that CHYS effectively prevents t-BHP-induced mtDNA leakage in renal tubular cells, preserving mitochondrial function and stability, an effect compromised by PRDX5 knockdown. Moreover, our protein binding assays uncover a previously unreported interaction between PRDX5 and TFAM, with TFAM knockdown reversing the mitochondrial functional and fibrotic improvements achieved through PRDX5 overexpression and CHYS intervention.

CONCLUSION

These findings introduce a pioneering perspective on CHYS's mechanism of action. CHYS enhance TFAM activation through PRDX5 upregulation, counteract ROS-induced mitochondrial damage, and restoring mitochondrial homeostasis, and alleviates the progression of renal fibrosis in CKD, highlighting the innovative therapeutic potential of CHYS in mitochondrial-related renal pathologies.

Enzymatic hydrolysis of acyl glucuronide metabolites in human liver microsomes correlates to the risk of idiosyncratic drug toxicity

Acyl glucuronide (AG) is a reactive metabolite that causes idiosyncratic drug toxicity (IDT). Although the instability of AG is used to predict the IDT risk of novel drug candidates, it sometimes overestimates the IDT risk. We investigated whether the rate of enzymatic AG hydrolysis in human liver microsomes (HLM) can predict the risk of IDT. We used 16 drugs classified into three categories in terms of IDT risk: drugs withdrawn from the market owing to severe IDT (withdrawn, WDN) and drugs still being on the market, regardless of IDT risk (warning, WA) or not (safe, SA). AG was incubated with HLM, and the resulting parent drugs for AG hydrolysis were quantified using HPLC. The rate of enzymatic AG hydrolysis in the HLM of WDN was higher than that in WA and SA, and no difference was observed between WA and SA. We categorized WA and SA as commercially available (CA) drugs and performed a logistic regression analysis. The rate of enzymatic AG hydrolysis in HLM significantly distinguished WDN drugs from CA drugs, with an estimated classification value of 0.189 nmol/min/mg protein. In conclusion, the rate of enzymatic AG hydrolysis in HLM may be useful for predicting the risk in drug development.

Protein palmitoylation in hepatic diseases: Functional insights and therapeutic strategies

BACKGROUND

Liver pathologies represent a spectrum of conditions ranging from fatty liver to the aggressive hepatocellular carcinoma (HCC), as well as parasitic infections, which collectively pose substantial global health challenges. S-palmitoylation (commonly referred to as palmitoylation), a post-translational modification (PTM) characterized by the covalent linkage of a 16-carbon palmitic acid (PA) chain to specific cysteine residues on target proteins, plays a pivotal role in diverse cellular functions and is intimately associated with the liver's physiological and pathological states.

AIM OF REVIEW

This study aims to elucidate how protein palmitoylation affects liver disease pathophysiology and evaluates its potential as a target for diagnostic and therapeutic interventions.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Recent studies have identified the key role of protein palmitoylation in regulating the development and progression of liver diseases. This review summarizes the intricate mechanisms by which protein palmitoylation modulates the pathophysiological processes of liver diseases and explores the potential of targeting protein palmitoylation modifications or the enzymes regulating this modification as prospective diagnostic biomarkers and therapeutic targets.

Deacylases-structure, function, and relationship to diseases

Reversible S-acylation plays a pivotal role in various biological processes, modulating protein functions such as subcellular localization, protein stability/activity, and protein-protein interactions. These modifications are mediated by acyltransferases and deacylases, among which the most abundant modification is S-palmitoylation. Growing evidence has shown that this rivalrous pair of modifications, occurring in a reversible cycle, is essential for various biological functions. Aberrations in this process have been associated with various diseases, including cancer, neurological disorders, and immune diseases. This underscores the importance of studying enzymes involved in acylation and deacylation to gain further insights into disease pathogenesis and provide novel strategies for disease treatment. In this Review, we summarize our current understanding of the structure and physiological function of deacylases, highlighting their pivotal roles in pathology. Our aim is to provide insights for further clinical applications.