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BaCKgRoUND aND aIMS: Acetaminophen (APAP) overdose induces severe liver injury and hepatic failure. While the activation of c-Jun NH 2 -terminal kinase ( JNK) has been implicated as a mechanism in APAP-induced liver injury, the hepatic defense system controlled by nuclear factor erythroid 2-related factor 2 (Nrf2) plays a central role in the mitigation of APAP toxicity. However, the link between the two signaling pathways in APAP-induced liver injury (AILI) remains unclear. appRoaCH aND ReSUltS: In this study, we demonstrated that the activation of JNK in mouse liver following exposure to APAP was correlated with the phosphorylation of Nrf2 and down-regulation of the antioxidant response element (ARE)-driven genes, NAD(P)H:quinone dehydrogenase 1, glutathione S-transferase α3, glutathione S-transferase M1, glutathione S-transferase M5, and aldo-keto reductase 1C. The JNK inhibitor, SP600125, or knockdown of JNK by infection of adenovirus expressing JNK small interfering RNA, ameliorated the APAP induced liver toxicity, and inhibited the phosphorylation of Nrf2 and down-regulation of detoxifying enzymes by stabilizing the transcription factor. Mechanistically, JNK antagonized Nrf2-and ARE-driven gene expression in a Kelch-like ECH-associated protein 1-independent manner. Biochemical analysis revealed that phosphorylated JNK (P-JNK) directly interacted with the Nrf2-ECH homology (Neh) 1 domain of Nrf2 and phosphorylated the serine-aspartateserine motif 1 (SDS1) region in the Neh6 domain of Nrf2.CoNClUSIoNS: Mass spectrometric analysis identified serine 335 in the SDS1 region of mNrf2 as the major phosphorylation site for modulation of Nrf2 ubiquitylation by P-JNK. This study demonstrates that Nrf2 is a target of P-JNK in AILI. Our finding may provide a strategy for the treatment of AILI. (Hepatology 2020;71:1787-1801. N -acetyl-p-aminophenol (APAP; acetaminophen) is a commonly used non-narcotic analgesic drug used to reduce fever and relieve

Jian-Pi-Yi-Shen formula (JPYSF) is a Chinese herbal decoction used for treating chronic kidney disease (CKD) for over 20 years with good efficiency. However, the mechanism lacks solid evidence. In the present study, we tested the hypothesis that JPYSF may retard CKD progression via inhibition of inflammation in 5/6 nephrectomy (5/6 Nx) rat model. The 5/6 Nx rats were randomly divided into 2 groups: 5/6 Nx group and JPYSF group. Sham-operated rats served as control. JPYSF (2.06 g/kg/d) were administrated by gavage to 5/6 Nx rats daily for 6 weeks. Results showed that JPYSF treatment significantly improved kidney function and pathological injury in 5/6 Nx rats. Multiplex analysis of cytokines revealed that JPYSF reduced proinflammatory cytokines and increased anti-inflammatory cytokine production. Furthermore, JPYSF inhibited the activation of nuclear factor-kappa B (NF-κB) signaling pathway. In conclusion, our data demonstrated that JPYSF remarkably retards development and progression of CKD in a 5/6 Nx rat model, which may be associated with inhibition of inflammation via NF-κB signaling pathway.

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