Ling-Gui-Zhu-Gan decoction protects against doxorubicin-induced myocardial injury by downregulating ferroptosis.

OBJECTIVE: To investigate the mechanism of Ling-Gui-Zhu-Gan decoction (LGZGD) protects against doxorubicin (DOX)-induced myocardial injury. METHODS: In vivo experiment, rats were divided into six groups: normal group, model group (15 mg/kg, DOX), Dex group(150 mg/kg, Dex), LGZGD-L group (2.1 g/kg), LGZGD-M group (4.2 g/kg), and LGZGD-H group (8.4 g/kg). We used HE and Masson staining to observe the histopathological changes, echocardiography to assess the cardiac function, and western blot and RT-qPCR to detect the expressions of Nrf2, GPX4, Fpn1, and Ptgs2. In vitro experiment, we used immunofluorescence to detect ROS production, and RT-qPCR to detect gene expression of GPX4, Fpn1, and Ptgs2. KEY FINDINGS: In vivo, LGZGD improved cardiac systolic function. LGZGD significantly reduced MDA, LDH, and CK levels, increased SOD activity, enhanced the protein expression of Nrf2, GPX4, and Fpn1, and decreased Ptgs2 levels. In vitro, LGZGD-containing serum significantly reduced ROS, increased the gene expression of GPX4 and Fpn1, and decreased the gene expression of Ptgs2. Furthermore, compared with the LGZGD (si-NC) group, the LGZGD (si-Nrf2) group had decreased gene expression of Nrf2, GPX4, and Fpn1 and increased gene expression of Ptgs2. CONCLUSIONS: LGZGD can ameliorate DOX-cardiotoxicity by activating the Nrf2 signaling pathway and inhibiting ferroptosis in cardiomyocytes.

The Protective Effect of Sheng Mai Yin on Diabetic Cardiomyopathy via NLRP3/Caspase-1 Pathway.

Sheng Mai Yin (SMY) has therapeutic effects on myocardial infarction (MI), heart failure (HF), diabetic cardiomyopathy (DCM), and myocarditis. To study whether SMY can relieve pyroptosis and play a protective role in diabetic cardiomyopathy, a molecular docking technique was used to predict the possible mechanism of SMY against DCM. Then, a DCM rat model was induced by intraperitoneal injection of streptozotocin (STZ), divided into 5 groups: the DM group (model), SMY-L group (2.7 mL/kg SMY), SMY-M group (5.4 mL/kg SMY), SMY-H group (10.8 mL/kg SMY), and Met group (120 mg/kg metformin). Rats in the CTL group (control) and DM group were given normal saline. After 8 weeks, the levels of blood glucose, lipids, and myocardial enzymes were detected according to the kit instructions. Cardiac function was detected by echocardiography. HE and Masson were used to observing the pathological changes, collagen deposition, and collagen volume fraction (CVF). The apoptosis rate of cardiomyocytes was determined by Tunel. The IL-1ß level was determined by ELISA and RT-PCR. The expressions of NLRP3, caspase-1, and GSDMD were measured using RT-PCR and Western blotting. The docking results suggested that SMY may act on NLRP3 and its downstream signal pathway. The in vivo results showed that SMY could reduce blood glucose and lipid levels, improve heart function, improve histopathological changes and myocardial enzymes, and alleviate cardiomyocyte apoptosis and myocardial fibrosis. SMY inhibited the mRNA and protein expressions of NLRP3, ASC, Caspase-1, and GSDMD and IL-1ß production. SMY can reduce DCM by regulating the NLRP3/caspase-1 signaling pathway, providing a new research direction for the treatment of DCM.

In vivo and in vitro protective effects of shengmai injection against doxorubicin-induced cardiotoxicity.

CONTEXT: Shengmai injection (SMI) has been used to treat heart failure. OBJECTIVE: This study determines the molecular mechanisms of SMI against cardiotoxicity caused by doxorubicin (DOX). MATERIALS AND METHODS: In vivo, DOX (15 mg/kg) was intraperitoneally injected in model, Dex (dexrazoxane), SMI-L (2.7 mL/kg), SMI-M (5.4 mL/kg), and SMI-H (10.8 mL/kg) for 7 consecutive days. Hematoxylin-eosin (HE) and Masson staining were used to evaluate histological changes, and cardiomyocyte apoptosis was identified using TdT-mediated dUTP nick-end labelling (TUNEL). Enzymatic indexes were determined. mRNA and protein expressions were analysed through RT-qPCR and Western blotting. In vitro, H9c2 cells were divided into control group, model group (2 mL 1 µM DOX), SMI group, ML385 group, and SMI + ML385 group, the intervention lasted for 24 h. mRNA and protein expressions were analysed. RESULTS: SMI markedly improved cardiac pathology, decreased cardiomyocyte apoptosis, increased creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), decreased superoxide dismutase (SOD). Compared with the model group, the protein expression of nuclear factor erythroid2-related factor 2 (Nrf2) (SMI-L: 2.42-fold, SMI-M: 2.67-fold, SMI-H: 3.07-fold) and haem oxygenase-1(HO-1) (SMI-L: 1.64-fold, SMI-M: 2.01-fold, SMI-H: 2.19-fold) was increased and the protein expression of kelch-like ECH-associated protein 1 (Keap1) (SMI-L: 0.90-fold, SMI-M: 0.77-fold, SMI-H: 0.66-fold) was decreased in SMI groups and Dex group in vivo. Additionally, SMI dramatically inhibited apoptosis, decreased CK, LDH and MDA levels, and enhanced SOD activity. Our results demonstrated that SMI reduced DOX-induced cardiotoxicity via activation of the Nrf2/Keap1 signalling pathway. CONCLUSIONS: This study revealed a new mechanism by which SMI alleviates DOX-induced 45 cardiomyopathy by modulating the Nrf2/Keap1 signal pathway.