[Mechanisms of NLRP3 inflammasome-mediated pyroptosis in chronic heart failure and research progress in traditional Chinese medicine].

Chronic heart failure(CHF) is a severe cardiovascular disease characterized by a complex pathogenesis involving myocardial structural and functional abnormalities and the activation of inflammatory responses. The NOD-like receptor thermal protein domain-associated protein 3(NLRP3) inflammasome, acting as a sensor for inflammatory cells, plays a pivotal role in the development of CHF. Research indicates that the activation of the NLRP3 inflammasome can induce inflammatory responses, leading to cardiac inflammation and impairing myocardial function, and it is correlated with the severity of CHF. Traditional Chinese medicine(TCM) has garnered increasing attention as a traditional therapeutic approach in recent years. Various TCM drugs and treatment methods have exhibited potential efficacy in suppressing inflammatory responses, alleviating myocardial cell pyroptosis, improving myocardial structure and function, and inhibiting myocardial fibrosis. Several TCM drugs and their extracts have been utilized in CHF treatment, with mechanisms potentially involving the inhibition of NLRP3 inflammasomes and the mitigation of inflammatory responses. The article provided an overview of the composition, structural characteristics, initiation, and activation modes of the NLRP3 inflammasome, its mechanisms in CHF, and the research progress of TCM in CHF treatment. It aims to offer references and foundations for a deeper understanding of CHF pathogenesis and subsequent development of new therapeutic strategies.

[Shenfu Injection regulates macrophage polarization via TLR4/NF-κB pathway to reduce inflammation in chronic heart failure].

This study aimed to investigate the therapeutic effect of Shenfu Injection on mice with chronic heart failure(CHF) and its effect on macrophage polarization. C57BL/6J mice were randomly assigned to the normal and model groups. The CHF model was established by intraperitoneal injection of isoproterenol(ISO, 7.5 mg·kg~(-1), 28 d). The successful modeling was determined by asses-sing the cardiac function and N-terminal pro-brain natriuretic peptide(NT-proBNP). The modeled mice were randomly divided into the model group, Shenfu Injection group, and TAK-242 group, and were injected intraperitoneally with the corresponding drugs for 15 days. Cardiac function was evaluated using echocardiography. Hematoxylin-eosin(HE) staining was used to detect the pathomorphology. Enzyme-linked immunosorbent assay(ELISA) was used to detect the values of serum NT-proBNP, interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), IL-10, and arginase 1(Arg-1). Flow cytometry was applied to detect the relative content and M1/M2 polarization of cardiac macrophages. Quantitative polymerase chain reaction(qPCR) and Western blot were used to detect the changes in the Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB) pathway-related mRNA and protein expressions. Compared with the normal group, mice in the model group had lower values of left ventricular ejection fraction(LVEF) and left ventricular fractional shorte-ning(LVFS), higher values of left ventricular internal diastolic end-diastolic(LVIDd), left ventricular internal diastolic end-systolic(LVIDs), NT-proBNP, TNF-α, and IL-6(P<0.01); the number of macrophages increased in cardiac tissues(P<0.05), and the values of M1-F4/80~+CD86~+ were increased(P<0.01), while the values of M2-F4/80~+CD163~+ decreased(P<0.05); the mRNA and protein expressions of TLR4, myeloid differentiation factor 88(MyD88), IκB kinase α(IKKα), and NF-κB p65 in myocardial tissues were significantly elevated(P<0.05, P<0.01). Compared with the model group, mice in the Shenfu Injection and TAK-242 groups showed elevated LVEF, LVFS, IL-10, and Arg-1 levels, and decreased LVIDd, LVIDs, NT-proBNP, TNF-α, and IL-6 levels(P<0.05, P<0.01); the cardiac F4/80~+CD11b~+(macrophage) and M1-F4/80~+ CD86~+ values were significantly down-regulated, while M2-F4/80~+CD163~+ values were increased(P<0.05, P<0.01); and the mRNA and protein expressions of TLR4, MyD88, IKKα, and NF-κB p65 in myocardial tissues were notably decreased(P<0.05, P<0.01). CHF mice have an imbalance of M1/M2 macrophage polarization, with M1-type macrophages predominating. Shenfu Injection promotes macrophage polarization towards M2, inhibits M1-type macrophage activation, and attenuates inflammatory responses in heart failure by regulating the TLR4/NF-κB signaling pathway.

[Pathogenesis of chronic heart failure in rats based on ferroptosis-mediated oxidative stress and intervention effect of Shenfu Injection].

This study aims to investigate the pathogenesis of chronic heart failure based on ferroptosis-mediated oxidative stress and predict the targets of Shenfu Injection in treating chronic heart failure. A rat model of chronic heart failure was established by the isoproterenol induction method. According to the random number table method, the modeled rats were assigned into three groups: a model group, a Shenfu Injection group, and a ferrostatin-1(ferroptosis inhibitor) group. In addition, a normal group was designed. After 15 days of intervention, the cardiac mass index and left ventricular mass index were determined. Echocardiography was employed to eva-luate the cardiac function. Hematoxylin-eosin staining and Masson staining were employed to reveal the pathological changes and fibrosis of the heart, and Prussian blue staining to detect the aggregation of iron ions in the myocardial tissue. Transmission electron microscopy was employed to observe the mitochondrion ultrastructure in the myocardial tissue. Colorimetry was adopted to measure the levels of iron metabolism, lipid peroxidation, and antioxidant indicators. Flow cytometry was employed to measure the content of lipid-reactive oxygen species(ROS) and the fluorescence intensity of ROS. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of ferroptosis-related factors in the myocardial tissue. The results showed that the rats in the model group had reduced cardiac function, elevated levels of total iron and Fe~(2+), lowered level of glutathione(GSH), increased malondialdehyde(MDA), decreased superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px), and rising levels of ROS and lipid-ROS. In addition, the model group showed fibrous tissue hyperplasia with inflammatory cell infiltration and myocardial fibrosis, iron ion aggregation, and characteristic mitochondrial changes specific for iron death. Moreover, the model group showcased upregulated protein and mRNA levels of p53 and COX2 and downregulated protein and mRNA levels of GPX4, FTH1, SLC7A11, and Nrf2 in the myocardial tissue. The intervention with Shenfu Injection significantly improved the cardiac function, recovered the iron metabolism, lipid peroxidation, and antioxidant indicators, decreased iron deposition, improved mitochondrial structure and function, and alleviated inflammatory cell infiltration and fibrosis. Furthermore, Shenfu Injection downregulated the mRNA and protein levels of p53 and COX2 and upregulated the mRNA and protein levels of GPX4, FTH1, SLC7A11, and Nrf2 in the myocardial tissue. Shenfu Injection can improve the cardiac function by regulating iron metabolism, inhibiting ferroptosis, and reducing oxidative stress injury.

[Protective effect of Shenfu Injection on regulation of autophagy in rats with chronic heart failure based on PI3K/Akt/mTOR pathway].

This study aimed to investigate the mechanism and target sites of Shenfu Injection in the intervention of chronic heart fai-lure based on the PI3K/Akt/mTOR autophagy signaling pathway. The chronic heart failure model was induced in rats by subcutaneous injection of isoproterenol. The model rats were randomly divided into model group, Shenfu Injection group, and 3-methyladenine autophagy inhibitor(3-MA) group. A normal group was also set up. After 15 days of administration, cardiac function indexes of the rats were detected by echocardiography. The serum N-terminal pro-B-type natriuretic peptide(NT-proBNP) levels were measured using the ELISA. HE and Masson staining was performed to observe the morphological changes in myocardial tissues, and electron microscopy was used to observe the autophagosomes in myocardial tissues. Western blot was conducted to measure the changes in autophagy-related proteins(LC3 Ⅱ/Ⅰ and p62), PI3K, Akt, mTOR, and phosphorylation levels. The results showed that compared with normal group, model group in rats led to reduced cardiac function, significant activation of cardiac autophagy, increased fibrotic lesions in myocardial tissues, structural disorder of the myocardium, increased autophagosomes, and cytoplasmic vacuolization. Compared with model group, Shenfu Injection group in rats led to cardiac function significantly improved, myocardial fibrosis decreased, and the number of autophagosomes and cytoplasmic vacuolization decreased. The phosphorylation levels of PI3K, Akt, and mTOR were significantly increased(P<0.01). In the 3-MA group, autophagy was inhibited through the activation of the PI3K/Akt/mTOR signaling pathway, resulting in improved cardiac function, reduced myocardial fibrosis, and no significant cytoplasmic vacuolization. The findings suggest that Shenfu Injection can activate the PI3K/Akt/mTOR signaling pathway and inhibit autophagy, thereby improving cardiac function.

[Shenfu Injection improves chronic heart failure by regulating pyroptosis based on NLRP3/caspase-1 pathway].

This study investigated the mechanisms and targets of Shenfu Injection in the intervention in chronic heart failure(CHF) through the NOD-like receptor thermal protein domain associated protein 3(NLRP3)/caspase-1 signaling pathway. A CHF model was induced in rats by subcutaneous injection of isoproterenol. Model rats were randomly divided into a model group, a Shenfu Injection group, and a MCC950(NLRP3 inhibitor) group, and a blank group was also set up as a control. After 15 days of treatment, echocardiography was performed to measure cardiac function parameters [left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS)]. Enzyme-linked immunosorbent assay(ELISA) was used to measure serum levels of N-terminal pro-brain natriuretic peptide(NT-proBNP), interleukin(IL)-1ß, and IL-18. Hematoxylin-eosin(HE) and Masson staining were used to observe morphological changes in myocardial tissues, and Western blot was used to measure the expression levels of NLRP3/caspase-1 pathway-related proteins [NLRP3, caspase-1, apoptosis-associated speck-like protein containing a CARD(ASC), gasdermin D(GSDMD), IL-1ß, and IL-18]. The study found that isoproterenol-induced CHF in rats resulted in decreased cardiac function, worsened myocardial fibrosis, increased expression levels of NLRP3, ASC, caspase-1, GSDMD-N, IL-1ß, and IL-18 in myocardial tissues, elevated serum inflammatory factors, and induced myocardial cell pyroptosis. Following Shenfu Injection intervention, the Shenfu Injection group showed significantly improved LVEF and LVFS, a significant decrease in NT-proBNP, a marked downregulation of NLRP3, ASC, caspase-1, GSDMD-N, IL-1ß, and IL-18 protein expression levels, reduced serum inflammatory factors IL-1ß and IL-18 expression in CHF rats, and a decrease in the rate of TUNEL-positive cells. Shenfu Injection can significantly improve cardiac function in CHF, inhibit myocardial fibrosis, and alleviate the progression of myocardial cell pyroptosis through the inhibition of the NLRP3/caspase-1 pathway.