Shensong Yangxin Capsule Reduces the Susceptibility of Arrhythmia in db/db Mice via Inhibiting the Inflammatory Response Induced by Endothelium Dysfunction.

Purpose: The aim of our study was to investigate the mechanism by which the Chinese compound Shensong Yangxin Capsule (SSYX) reduces susceptibility to arrhythmia in db/db mice. Methods: The db/db mice without drug treatment served as the model group. Other-treated db/db mice were administered SSYX for 8 weeks. Electrocardiogram (ECG), electrical mapping, pathological changes, immunofluorescence staining, real-time quantitative PCR, and Western blot analyses were then conducted. Results: SSYX decreased arrhythmia susceptibility and shortened the abnormal ECG parameters of db/db mice. Meanwhile, SSYX restored irregular conduction direction and shortened the conduction time of the isolated heart. HE and Masson staining showed that SSYX alleviated inflammatory infiltration and collagen fiber deposition. Western blot showed that SSYX decreased the protein expression of ICAM-1, VCAM-1, and MCP-1 and increased the protein expression of occludin, ZO-1, eNOS, and Cx43. SSYX also increased the content of NO, decreased ET-1, TNF-α, IL-1ß, IL-6, MCP-1, and CCR-2 mRNA expression, and increased Kv 4.2, Kv 4.3, Cav 1.2, and Nav 1.5 mRNA expression. Furthermore, SSYX decreased the fluorescence intensity of F4/80 and iNOS, increased the fluorescence intensity of CD31 and eNOS, and improved the Cx43 and α-actinin connection structure in cardiac tissues. The above therapeutic effects of SSYX were inhibited by L-NAME. Conclusion: SSYX reduced the susceptibility of db/db mice to arrhythmia by inhibiting the inflammatory response and macrophage polarization, and this effect of SSYX occurred through protection of endothelial cell function.

Bazi Bushen mitigates epigenetic aging and extends healthspan in naturally aging mice.

Bazi Bushen (BZBS), a traditional Chinese medicine, has been proven effective in the treatment of age-related disease in mouse models. However, whether its therapeutic effects are due to antiaging mechanism has not yet been explored. In the present study, we investigated the antiaging effects of BZBS in naturally aging mice by using behavioral tests, liver DNA methylome sequencing, methylation age estimation, and frailty index assessment. The methylome analysis revealed a decrease of mCpG levels in the aged mouse liver. BZBS treatment tended to restore age-associated methylation decline and prune the methylation pattern toward that of young mice. More importantly, BZBS significantly rejuvenated methylation age of the aged mice, which was computed by an upgraded DNA methylation clock. These results were consistent with enhanced memory and muscular endurance, as well as decreased frailty score and liver pathological changes. KEGG analysis together with aging-related database screening identified methylation-targeted pathways upon BZBS treatment, including oxidative stress, DNA repair, MAPK signaling, and inflammation. Upregulation of key effectors and their downstream effects on elevating Sod2 expression and diminishing DNA damage were further investigated. Finally, in vitro experiments with senescent HUVECs proved a direct effect of BZBS extracts on the regulation of methylation enzymes during cellular aging. In summary, our work has revealed for the first time the antiaging effects of BZBS by slowing the methylation aging. These results suggest that BZBS might have great potential to extend healthspan and also explored the mechanism of BZBS action in the treatment of age-related diseases.

Tongxinluo Attenuates Myocardiac Fibrosis after Acute Myocardial Infarction in Rats via Inhibition of Endothelial-to-Mesenchymal Transition.

Endothelial-to-mesenchymal transition (EndMT) is an essential mechanism in myocardial fibrosis (MF). Tongxinluo (TXL) has been confirmed to protect the endothelium against reperfusion injury after acute myocardial infarction (AMI). However, whether TXL can inhibit MF after AMI via inhibiting EndMT remained unknown. This study aims to identify the role of EndMT in MF after AMI as well as the protective effects and underlying mechanisms of TXL on MF. The AMI model was established in rats by ligating left anterior descending coronary artery. Then, rats were administered with high- (0.8 g·kg-1·d-1), mid- (0.4 g·kg-1·d-1), and low- (0.2 g·kg-1·d-1) dose Tongxinluo and benazepril for 4 weeks, respectively. Cardiac function, infarct size, MF, and related indicators of EndMT were measured. In vitro, human cardiac microvascular endothelial cells (HCMECs) were pretreated with TXL for 4 h and then incubated in hypoxia conditions for 3 days to induce EndMT. Under this hypoxic condition, neuregulin-1 (NRG-1) siRNA were further applied to silence NRG-1 expression. Immunofluorescence microscopy was used to assess expression of endothelial marker of vWF and fibrotic marker of Vimentin. Related factors of EndMT were determined by Western blot analysis. TXL treatment significantly improved cardiac function, ameliorated MF, reduced collagen of fibrosis area (types I and III collagen) and limited excessive extracellular matrix deposition (mmp2 and mmp9). In addition, TXL inhibited EndMT in cardiac tissue and hypoxia-induced HCMECs. In hypoxia-induced HCMECs, TXL increased the expression of endothelial markers, whereas decreasing the expression of fibrotic markers, partially through enhanced expressions of NRG-1, phosphorylation of ErbB2, ErbB4, AKT, and downregulated expressions of hypoxia inducible factor-1a and transcription factor snail. After NRG-1 knockdown, the protective effect of TXL on HCMEC was partially abolished. In conclusion, TXL attenuates MF after AMI by inhibiting EndMT and through activating the NRG-1/ErbB- PI3K/AKT signalling cascade.

Qiliqiangxin Attenuates Oxidative Stress-Induced Mitochondrion-Dependent Apoptosis in Cardiomyocytes via PI3K/AKT/GSK3ß Signaling Pathway.

Qiliqiangxin capsule (QLQX) is a well-known traditional Chinese medicine that exhibits cardioprotective effects in heart failure patients. However, it remains unclear whether and by which mechanism QLQX attenuates oxidative stress-induced mitochondria-dependent myocardial apoptosis. In vivo, Sprague Dawley (SD) rats received left anterior descending coronary artery ligation for 4 weeks to establish a model of heart failure after acute myocardial infarction, and then were treated with QLQX for another 4 weeks. We evaluated cardiac function, oxidative stress injury, as well as the expressions of mitochondria-dependent apoptosis and its signaling factors. The results indicated that QLQX protected cardiac function and attenuated oxidative stress-induced myocardial apoptosis. Meanwhile, QLQX elevated the Bcl-2 expression, declined the expressions of Bax, cytochrome c, apoptotic protease activating factor-1 (Apaf-1), cleaved-caspase 9 and cleaved-caspase 3, and up-regulated the ratios of phospho-AKT/AKT and phospho-glycogen synthase kinase-3ß (GSK3ß)/GSK3ß. In vitro, H9c2 cardiomyocytes were pretreated with QLQX, then exposed to H2O2 for 24 h. QLQX promoted the proliferation of H9c2 cardiomyocytes induced by H2O2 and reversed oxidative stress damage. Moreover, QLQX inhibited the apoptosis rate and the pro-apoptosis protein expressions, but improved the Bcl-2 expression as well as the ratios of phospho-AKT/AKT and phospho-GSK3ß/GSK3ß. Meanwhile, it further ameliorated mitochondrion-related apoptosis by inhibiting the mitochondrial fission, mitochondrial permeability transition pore (MPTP) opening, and mitochondrial membrane potential (MMP) decline in H9c2 cardiomyocytes induced by H2O2. In addition, all the effects of QLQX on H2O2-induced mitochondria-dependent apoptosis could be blocked by the phosphoinositide 3-kinase (PI3K) inhibitor, LY294002. We conclude that QLQX may ameliorate oxidative stress-induced mitochondria-dependent apoptosis in cardiomyocytes through PI3K/AKT/GSK3ß signaling pathway.

Tongxinluo Regulates Expression of Tight Junction Proteins and Alleviates Endothelial Cell Monolayer Hyperpermeability via ERK-1/2 Signaling Pathway in Oxidized Low-Density Lipoprotein-Induced Human Umbilical Vein Endothelial Cells.

Vascular hyperpermeability resulting from distortion of endothelial junctions is associated with a number of cardiovascular diseases. Endothelial tight junction regulates the paracellular permeability of macromolecules, a function of Human Umbilical Vein Endothelial Cells (HUVEC) monolayers that can be regulated by oxidized Low-density Lipoprotein (ox-LDL). However, the understanding of drug regulation of vascular hyperpermeability is so far limited. This study thus aimed to investigate the role of Tongxinluo (TXL) in the maintenance of the vascular endothelial paracellular permeability. Here, changes in permeability were determined by measuring the paracellular flux of FITC-dextran 40000 (FD40), while protein expression and intercellular distribution were examined by western blot and immunofluorescence assay, respectively. We found that TXL alleviated the ox-LDL-induced increase in flux of FD40 and then reduced the hyperpermeability. Moreover, ox-LDL-induced disruptions of ZO-1, occludin, and claudin1 were also restored. This is via the activation of ERK1/2 in the vascular endothelial cells. Our results provide insights into the molecular mechanism by which TXL alleviates ox-LDL-induced hyperpermeability and provide the basis for further investigations of TXL as regulators of vascular barrier function.

[Effect of Tongxinluo on Apoptosis of Rat Cardiac Microvascular Endothelial Cells].

OBJECTIVE: To observe the protective effects of Tongxinluo (TXL) on apoptosis of rat cardiac microvascular endothelial cells (RCMECs) resulting from homocysteine (Hcy) induced endoplasmic reticulum stress (ERS), and to determine the signaling pathway behind its protection. METHODS: Primary cultured RCMECs were isolated from neonatal rats using tissue explant method. The morphology of RCMECs was observed using inverted microscope, identified and differentiated by CD31 immunofluorescence method. Selected were well growing 2nd-4th generations of RCMECs. The optimal action time was determined by detecting the expression of glucose regulated protein 78 (GRP78) using immunofluorescence method. In the next experiment RCMECs were divided into 5 groups, i.e., the blank control group, the Hcy induced group (Hcy 10 mmol/L, 10 h), the Hcy + TXL group (Hcy 10 mmol/L + TXL 400 µg/mL), the Hcy +LY294002 group (Hcy 10 mmol/L + LY294002 5 µmol/L, LY294002 as the inhibitor of PI3K), the Hcy + LY294002 + TXL group (Hcy 10 mmol/L + LY294002 5 µmol/L + TXL 400 µg/mL). The apoptosis rate of RCMECs was detected by flow cytometry. mRNA and protein expressions of GRP78, C/ EBP homologous protein (CHOP), and cysteinyl aspartate specific proteinase-12 (caspase12) were detected by real-time reverse transcription PCR (RT-PCR) and Western blot respectively. Expression levels of phosphorylation of phosphatidylinositol 3-kinase (P-PI3K), total phosphatidylinositol 3-kinase (T- P13K) , phosphorylation of kinase B (P-Akt) , and total kinase B (T-Akt) were detected by Western blot. RESULTS: Ten hours Hcy action time was determined. Compared with the blank control group, the apoptosis rate was increased (22.77%), mRNA and protein expressions of GRP78, CHOP, and Caspase-12 were increased, protein expressions of P-PI3K and P-Akt,ratios of P-PI3K/T-PI3K and P-Akt/T-Akt were decreased in the Hcy induced group (P < 0.05, P < 0.01). Compared with the Hcy induced group, the apoptosis rate was decreased (10.17%), mRNA and protein expressions of GRP78, CHOP, and Caspase-12 were decreased, and expression levels of P-PI3K, P-Akt, P-PI3K/T-PI3K, and P-Akt/T-Akt were increased in the Hcy + TXL group (P < 0.05, P < 0.01). Compared with the Hcy + TXL group, the apoptosis rate was increased (17.9%), mRNA and protein expressions of GRP78, CHOP, and Caspase-12 were increased, expression levels of P-PI3K and P-Akt, ratios of P-PI3K/T-PI3K and P-Akt/T-Akt were decreased in the Hcy + TXL + LY294002 group (P < 0.05, P < 0.01). CONCLUSION: TXL could inhibit the apoptosis of RCMECs resulting from Hcy-induced ERS and its mechanism might be associated with activating PI3K/Akt signaling pathway.