Objective To explore the role and mechanism of puerarin in ameliorating acetaminophen(APAP)-induced acute liver injury in mice based on ferroptosis signaling pathway.Methods Twenty-four C57BL/6J mice were randomly divided into normal group,model group,and puerarin low-and high-dose groups(50 and 200 mg·kg-1),6 mice in each group;all the administration groups were given continuous gavage(10 mL·kg-1)once a day pre-dosed for 3 days.One hour after the last dose,APAP(300 mg·kg-1)was intraperitoneally injected into the mice of the model group and the puerarin low-and high-dose groups to replicate the drug-induced liver injury(DILI)mouse model.After 24 hours,the serum levels of alanine transaminase(ALT),aspartate aminotransferase(AST),and lactate dehydrogenase(LDH)were measured by the microplate assay;HE staining was used to observe the histopathological changes in liver tissue;the apoptosis of hepatocytes was observed by the TUNEL staining assay;the levels of malondialdehyde(MDA)were measured by the TBA assay;the mRNA expression levels of reactive oxygen species(ROS),4-hydroxynonenal(4-HNE),glutathione peroxidase 4(GPX4),and solute carrier family 7 member 11(SLC7A11)were detected by immunofluorescence;qRT-PCR was performed to measure the mRNA levels of ferroptosis-related genes GPX4,transferrin receptor(TFRC),and solute carrier family 11 member 2(SLC11A2)in liver tissue.Results Compared with the normal group,the serum ALT,AST,and LDH levels of mice in the model group were significantly elevated(P＜0.01);the liver lobules showed obvious damage,with swelling and rupture of hepatocytes,cytoplasmic vacuolisation,fragmentation of nuclei,congestion of the hepatic blood sinusoids and infiltration of inflammatory cells,and an increase in apoptotic cells;the level of MDA in the hepatic tissues was significantly elevated(P＜0.05);the red fluorescence(positive expression)of ROS and 4-HNE was significantly enhanced(P＜0.05,P＜0.01),and the red fluorescence(positive expression)of GPX4 and SLC7A11 was significantly weakened in liver tissue(P＜0.01);the mRNA expressions of GPX4 and SLC11A2 in liver tissue were significantly down-regulated(P＜0.05),and there was a tendency for the down-regulation of TFRC expression but the difference was not statistically significant(P＞0.05).Compared with the model group,the serum AST and LDH levels of mice in the low-and high-dose groups of puerarin were significantly reduced(P＜0.05,P＜0.01),and there was a decrease in serum ALT,but the difference was not statistically significant(P＞0.05);the structure of the liver lobules was clearer,with radial arrangement of hepatic cords,and the area of necrotic liver tissue and apoptotic cells were significantly reduced;the level of MDA in the liver tissue was significantly reduced(P＜0.05);the red fluorescence(positive expression)of ROS and 4-HNE in liver tissue were significantly attenuated(P＜0.05,P＜0.01).The red fluorescence(positive expression)of GPX4 and SLC7A11 in liver tissue of the mice in the puerarin low-dose group were significantly enhanced(P＜0.05,P＜0.01),and there was a tendency to enhance the red fluorescence(positive expression)of GPX4 and SLC7A11 in the liver tissue of the mice in the puerarin high-dose group,but the difference was not statistically significant(P＞0.05).The mRNA expressions of GPX4 and TFRC in liver tissue of mice in low-dose puerarin group was significantly up-regulated(P＜0.05),while the mRNA expressions of GPX4 and SLC11A2 in high-dose puerarin group were significantly up-regulated(P＜0.05).Conclusion Puerarin had a significant protective effect on APAP-DILI,which may be related to its inhibition of cellular ferroptosis through the SLC7A11/GPX4 pathway.

Background::Parkinson’s disease (PD) is the second most common neurodegenerative disease after Alzheimer’s dementia. Mitochondrial dysfunction is involved in the pathology of PD. Coiled-coil-helix-coiled-coil-helix domain-containing 2 (CHCHD2) was identified as associated with autosomal dominant PD. However, the mechanism of CHCHD2 in PD remains unclear.Methods::Short hairpin RNA (ShRNA)-mediated CHCHD2 knockdown or lentivirus-mediated CHCHD2 overexpression was performed to investigate the impact of CHCHD2 on mitochondrial morphology and function in neuronal tumor cell lines represented with human neuroblastoma (SHSY5Y) and HeLa cells. Blue-native polyacrylamide gel electrophoresis (PAGE) and two-dimensional sodium dodecyl sulfate-PAGE analysis were used to illustrate the role of CHCHD2 in mitochondrial contact site and cristae organizing system (MICOS). Co-immunoprecipitation and immunoblotting were used to address the interaction between CHCHD2 and Mic10. Serotype injection of adeno-associated vector-mediated CHCHD2 and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration were used to examine the influence of CHCHD2 in vivo.Results::We found that the overexpression of CHCHD2 can protect against methyl-4-phenylpyridinium (MPP+)-induced mitochondrial dysfunction and inhibit the loss of dopaminergic neurons in the MPTP-induced mouse model. Furthermore, we identified that CHCHD2 interacted with Mic10, and overexpression of CHCHD2 can protect against MPP +-induced MICOS impairment, while knockdown of CHCHD2 impaired the stability of MICOS. Conclusion::This study indicated that CHCHD2 could interact with Mic10 and maintain the stability of the MICOS complex, which contributes to protecting mitochondrial function in PD.

Hepatic stellate cell(HSC)activation is a key link in the development of liver fibrosis.The metabolic reprogramming of activated HSC has become a hot topic in current research,especially the change of glycolysis is an important factor in regulating HSC activation.Based on the metabolic reprogramming in the process of HSC activation,this paper expounds the mechanism of regulating HSC activation and liver fibrosis through glycolysis,and reviews the research progress of traditional Chinese medicine and its active ingredients in regulating HSC glycolysis to prevent and treat liver fibrosis.Liver fibrosis is a complex pathological process involving multiple factors and pathways.From the perspective of regulating the glycolysis of activated HSC,it can provide a new idea for the development of anti-liver fibrosis drugs.

ObjectiveTo clarify whether epigallocatechin gallate （EGCG） is involved in the clearance of amyloid β-protein （Aβ） and autophagy induction by microglia， so as to explore the potential mechanisms of EGCG in the prevention and treatment of Alzheimer's disease （AD）. MethodsSix-month-old APP/PS1 mice were randomly divided into model and EGCG groups， with some additional wild type （WT） mice as the control group， each group consisting of 15 mice. The EGCG group received continuous gavage administration［5 mg/（kg·d）］ for 8 weeks， followed by the open field test and Y-maze to assess the learning and memory abilities of the mice. Thioflavin-S staining was used to evaluate the content and distribution of amyloid β-protein （Aβ）in the brain parenchyma of the mice， and immunofluorescence was employed to detect the expression levels of Aβ_1-42， glial fibrillary acidic protein （GFAP）， and ionized calcium-binding adapter molecule 1 （Iba1） in the hippocampal tissue of the mice. Additionally， N9 mouse microglial cells were induced with 20 µmol/L Aβ_1-42， and the cell viability was measured after treatment with different concentrations of EGCG （5 µmol/L， 10 µmol/L， 20 µmol/L）. Western blotting was used to detect the levels of Aβ_1-42， low density lipoprotein receptor-related protein 1（LRP1）， receptor for advanced glycation endproducts （RAGE）， amyloid precursor protein （APP）， insulin degrading enzyme （IDE）， neprilysin （NEP）， microtubule associated protein 1 hydrogen chain 3（LC3）-Ⅱ/LC3-Ⅰ， phosphatidylinositol 3-hydroxy kinase（PI3K）， p-PI3K， protein kinase B （AKT）， p-AKT， mammalian target of rapamycin （mTOR）， p-mTOR， and histone deacetylase 6（HDAC6）. Finally， through the co-culture of microglial cells and neuronal SH-SY5Y cells， cell viability and Caspase-3 levels were measured to verify the protective effect of EGCG-mediated Aβ clearance on neurons. ResultsEGCG increased the activity time and frequency of APP/PS1 mice in the central area of the open field （P<0.05）， and enhanced the percentage of alternation in the Y-maze test （P<0.01）； EGCG reduced Aβ deposition in the hippocampal tissue of APP/PS1 mice and increased the number of microglia； in vitro experiments showed that EGCG improved the survival rate of Aβ-induced N9 cells （P<0.01）， upregulated RAGE activity （P<0.05）， and promoted the internalization and phagocytosis of Aβ （P<0.01）. ECGC activated microglial autophagy by downregulating the level of HDAC6 （P<0.05）， inhibiting the phosphorylation of PI3K， AKT， mTOR （P<0.001）， and increasing the LC3-Ⅱ/LC3-I ratio （P<0.001）； EGCG improved the survival rate of SH-SY5Y cells （P<0.05） and reduced the activity of Caspase-3 （P<0.01） by clearing Aβ_1-42 through microglia， and had a protective effect on neurons. ConclusionEGCG activates microglial autophagy to clear Aβ by targeting and inhibiting the HDAC6-PI3K/AKT/mTOR axis.