Oxidative stress is the main cause of acute myocardial infarction (AMI), which is related to the disorder of the regulation of Bmal1 on the redox state. HSPB1 form homologous‐oxidized HSPB1 (homooxidized HSPB1) to resist oxidative damage via S‐thiolated modification. However, it is still unclarified whether there is an interaction between the circadian clock and HSPB1 in myocardial injury. A total of 118 AMI patients admitted and treated in our hospital from Sep. 2019 to Sep. 2020 were selected to detect the plasma HSPB1 expression and the redox state. We divided the AMI patients into three subgroups: morning‐onset AMI (5 : 00 am to 8 : 00 am; Am‐subgroup, n = 38), noon‐onset AMI (12 : 00 pm to 15 : 00; Pm‐subgroup, n = 45), and night‐onset AMI (20 : 00 pm to 23 : 00 pm; Eve‐subgroup, n = 35) according to the circadian rhythm of onset. The Am‐subgroup had remarkably higher cardiac troponin I (cTnI), creatine kinase MB (CK‐MB), and B‐type natriuretic peptide (BNP) but lower left ventricular ejection fraction (LVEF) than the Pm‐subgroup and Eve‐subgroup. Patients complicated with cardiogenic shock were significantly higher in the Am‐subgroup than in the other two groups. The homooxidized HSPB1 in plasma markedly decreased in the Am‐subgroup. The HSPB1C141S mutant accelerated H9c2 cell apoptosis, increased reactive oxygen species (ROS), and decreased reduced‐glutathione (GSH) and the ratio of reduced‐GSH and GSSG during oxidative stress. Importantly, we found that the redox state of HSPB1 was consistent with the oscillatory rhythm of Bmal1 expression in normal C57B/L mice. The circadian rhythm disorder contributed to decrease Bmal1 and homooxidized HSPB1 in cardiomyocytes of C57BL/6 mice. In addition, Bmal1 and homooxidized HSPB1 decreased in neonatal rat cardiomyocytes exposed to H₂O₂. Knockdown of Bmal1 led to significant attenuation in homooxidized HSPB1 expression, whereas overexpression of Bmal1 increased homooxidized HSPB1 expression in response to H₂O₂. Our findings indicated that the homooxidized HSPB1 reduced probably the AMI patients’ risk of shock and target organ damage, which was associated with Bmal1 regulating the redox state of HSPB1.

Objective: Paraquat (PQ) is a toxic compound that selectively accumulates in the lungs, inducing severe pulmonary inflammation and fibrosis. However, data on the metabolomic changes induced by the PQ remain scant. This study aimed to determine the metabolic changes in Sprague–Dawley rats subjected to PQ using UPLC-Q-TOF-MS/MS. Methods: We established groups of PQ-induced pulmonary injury rats for 14 or 28 days. Results: Our data showed that PQ decreased the survival of the rats and induced pulmonary inflammation at day 14 or pulmonary fibrosis at day 28. There was upregulation of IL-1β expression in the inflammation group as well as upregulation of fibronectin, collagen and α-SMA in the pulmonary fibrosis group. OPLS-DA revealed differential expression of 26 metabotites between the normal and the inflammation groups; 31 plasma metabotites were also differently expressed between the normal and the fibrosis groups. There was high expression of lysoPc160-, hydroxybutyrylcarnitine, stearic acid, and imidazolelactic acid in the pulmonary injury group compared to the normal group. Conclusion: Metabolomics analysis confirmed that the PQ-induced lung injury was not only related to the aggravation of inflammation and apoptosis but also to mediated histidine, serine, glycerophospholipid, and lipid metabolism. This study gives insights into the mechanisms of PQ-induced lung injury and highlights the potential therapeutic targets. Nonstructured The effect of PQ on lung injury in rats was detected by metabonomics, and the possible metabolic mechanism was investigated by KEGG analysis. OPLS-DA revealed the differential expression of 26 metabotites and 31 plasma metabotites between the normal and the pulmonary injury groups. Metabolomics analysis confirmed that the PQ-induced lung injury was not only related to the aggravation of inflammation and apoptosis but also to mediated histidine, serine, glycerophospholipid, and lipid metabolism. Oleoylethanolamine, stearic acid, and imidazolelactic acid are potential molecular markers in PQ-induced pulmonary injury.