ABSTRACT
OBJECTIVE@#Acute liver failure (ALF) is characterized by severe liver dysfunction, rapid progression and high mortality and is difficult to treat. Studies have found that sulforaphane (SFN), a nuclear factor E2-related factor 2 (NRF2) agonist, has anti-inflammatory, antioxidant and anticancer effects, and has certain protective effects on neurodegenerative diseases, cancer and liver fibrosis. This paper aimed to explore the protective effect of SFN in ALF and it possible mechanisms of action.@*METHODS@#Lipopolysaccharide and D-galactosamine were used to induce liver injury in vitro and in vivo. NRF2 agonist SFN and histone deacetylase 6 (HDAC6) inhibitor ACY1215 were used to observe the protective effect and possible mechanisms of SFN in ALF, respectively. Cell viability, lactate dehydrogenase (LDH), Fe2+, glutathione (GSH) and malondialdehyde (MDA) were detected. The expression of HDAC6, NRF2, glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4) and solute carrier family 7 member 11 (SLC7A11) were detected by Western blotting and immunofluorescence.@*RESULTS@#Our results show that NRF2 was activated by SFN. LDH, Fe2+, MDA and ACSL4 were downregulated, while GSH, GPX4 and SLC7A11 were upregulated by SFN in vitro and in vivo, indicating the inhibitory effect of SFN on ferroptosis. Additionally, HDAC6 expression was decreased in the SFN group, indicating that SFN could downregulate the expression of HDAC6 in ALF. After using the HDAC6 inhibitor, ACY1215, SFN further reduced HDAC6 expression and inhibited ferroptosis, indicating that SFN may inhibit ferroptosis by regulating HDAC6 activity.@*CONCLUSION@#SFN has a protective effect on ALF, and the mechanism may include reduction of ferroptosis through the regulation of HDAC6. Please cite this article as: Zhang YQ, Shi CX, Zhang DM, Zhang LY, Wang LW, Gong ZJ. Sulforaphane, an NRF2 agonist, alleviates ferroptosis in acute liver failure by regulating HDAC6 activity. J Integr Med. 2023; 21(5): 464-473.
Subject(s)
Humans , Ferroptosis , NF-E2-Related Factor 2/genetics , Liver Failure, Acute/drug therapy , Isothiocyanates/pharmacology , Glutathione , Histone Deacetylase 6ABSTRACT
<p><b>BACKGROUND</b>Studies suggested that anesthetics administered upon the early reperfusion or "anesthetic postconditioning" could protect post-ischemic hearts against myocardial ischemia reperfusion injury (MIRI). However, the mechanism responsible for such protection was not well-elucidated. We investigated the cardioprotection induced by sevoflurane postconditioning (SpostC) in rat hearts in vitro, and the respective role of phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated kinase 1 and 2 (ERK 1/2), mitochondrial K(ATP) channels (mitoK(ATP)) and mitochondrial permeability transition pore (mPTP), by selectively inhibiting PI3K, ERK 1/2, mitoK(ATP), with LY294002 (LY), PD98059 (PD), 5-hydroxydecanoate (5-HD) and by directly opening of mPTP with atractyloside (ATR), respectively.</p><p><b>METHODS</b>Isolated rat hearts were randomly assigned to one of the 12 groups (n = 15): Time control (continuous perfusion), ISCH (30 minutes of ischemia followed by 60 minutes of reperfusion alone), SpostC (3% sevoflurane postconditioning was administered during the first 15 minutes of reperfusion after 30 minutes of ischemia), ISCH + LY, ISCH + PD, ISCH + ATR, ISCH + 5-HD and ISCH + dimethyl sulfoxide (DMSO) groups (LY, PD, ATR, 5-HD and DMSO (the vehicle) was administered respectively during the first 15 minutes of reperfusion following test ischemia), SpostC + LY, SpostC + PD, SpostC + ATR and SpostC + 5-HD groups (LY, PD, ATR and 5-HD was coadministered with 3% sevoflurane, respectively). Hemodynamics was compared within and between groups. Infarction size was determined at the end of experiments using triphenyltetrazolium chloride (TTC) staining. Lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) released from necrotic myocardium, were compared among TC, ISCH and SpostC groups. To investigate the relationships between RISK and mPTP implicated in SpostC, NAD(+) content in myocardium, a marker of mPTP opening, was compared among some experimental groups (TC, ISCH, ISCH + LY, ISCH + PD, ISCH + DMSO, SpostC, SpostC + LY, SpostC + PD). To further investigate whether the anti-apoptotic mechanism is implicated in SpostC-induced cardioprotection and its association with mitochondria, TUNEL staining was performed in some experimental groups (TC, ISCH, ISCH + 5-HD, ISCH + ATR, ISCH + DMSO, SpostC, SpostC + 5-HD, SpostC + ATR).</p><p><b>RESULTS</b>When compared with unprotected hearts subjected to 30 minutes of ischemia, exposure to 3% sevoflurane for 15 minutes during early reperfusion significantly improved functional recovery, decreased myocardial infarct size, decreased LDH, CK-MB and cTnI release, and decreased cardiomyocyte apoptosis (P < 0.05). However, such cardioprotective effects of hemodynamic recovery and infarct size reduction by sevoflurane was completely abolished by any one of LY294002, PD98059, atractyloside and 5-hydroxydecanoate (P < 0.05). Additionally, either LY294002 or PD98059 could reverse the inhibitory effect of SpostC over mPTP opening upon reperfusion (P < 0.05). Both atractyloside and 5-hydroxydecanoate could abrogate the anti-apoptotic effects of SpostC (P < 0.05).</p><p><b>CONCLUSION</b>These findings demonstrate that PI3K, ERK 1/2, mitoK(ATP) and mPTP are key players in sevoflurane postconditioning induced cardioprotective mechanisms in isolated rat hearts subjected to MIRI.</p>