Yanda Li

Oxidative Stress-Mediated Atherosclerosis: Mechanisms and Therapies

Atherogenesis, the formation of atherosclerotic plaques, is a complex process that involves several mechanisms, including endothelial dysfunction, neovascularization, vascular proliferation, apoptosis, matrix degradation, inflammation, and thrombosis. The pathogenesis and progression of atherosclerosis are explained differently by different scholars. One of the most common theories is the destruction of well-balanced homeostatic mechanisms, which incurs the oxidative stress. And oxidative stress is widely regarded as the redox status realized when an imbalance exists between antioxidant capability and activity species including reactive oxygen (ROS), nitrogen (RNS) and halogen species, non-radical as well as free radical species. This occurrence results in cell injury due to direct oxidation of cellular protein, lipid, and DNA or via cell death signaling pathways responsible for accelerating atherogenesis. This paper discusses inflammation, mitochondria, autophagy, apoptosis, and epigenetics as they induce oxidative stress in atherosclerosis, as well as various treatments for antioxidative stress that may prevent atherosclerosis.

Effects of exercise-based cardiac rehabilitation in patients after percutaneous coronary intervention: A meta-analysis of randomized controlled trials.

In this study, we assessed the effect of rehabilitation exercise after percutaneous coronary intervention (PCI) in patients with coronary heart disease (CHD). We performed a meta-analysis to determine the effects of exercise in patients after PCI. The Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, the Embase database, China National Knowledge Internet (CNKI), China Biology Medicine (CBM), and the Wanfang Database were searched for randomized controlled trials (RCTs). The key words used for the searches were PCI, exercise, walking, jogging, Tai Chi, and yoga. Six studies with 682 patients met our inclusion criteria; we chose the primary endpoint events of cardiac death, recurrence of myocardial infarction (MI), repeated PCI, coronary artery bypass grafting (CABG), and restenosis, and the secondary endpoint measures included recurrent angina, treadmill exercise (total exercise time, ST-segment decline, angina, and maximum exercise tolerance). The results showed that exercise was not clearly associated with reductions in cardiac death, recurrence of MI, repeated PCI, CABG, or restenosis. However, the exercise group exhibited greater improvements in recurrent angina, total exercise time, ST-segment decline, angina, and maximum exercise tolerance than did the control group. Future studies need to expand the sample size and improve the quality of reporting of RCTs.

Meta-Analysis of the Effects of Xingnaojing Injection on Consciousness Disturbance.

AbstractXingnaojing (XNJ) is commonly extracted from Angongniuhuang, a classic Chinese emergency prescription, and widely used in the treatment of nervous system disorders including consciousness disturbance in China.To evaluate the beneficial and adverse effects of XNJ injection, on consciousness disturbance.Seven major electronic databases were searched to retrieve randomized controlled trials designed to evaluate the clinical efficacy of XNJ alone or combined with Western medicine in treating consciousness disturbance caused by conditions such as high fever, poisoning, and stroke. The methodological quality of the included studies was assessed using criteria from the Cochrane Handbook for Systematic Review of Interventions, and analyzed using the RevMan 5.3.0 software.Seventeen randomized controlled trials on XNJ were included in this study and the trials generally showed low methodological quality. The results revealed that XNJ alone or in combination with other medicines and adjuvant methods had a positive effect on patients with fever-, poisoning-, and stroke-induced coma.XNJ effectively treated consciousness disturbances that were caused by high fever, poisoning, or stroke.

Effects of Wenxin Keli on Cardiac Hypertrophy and Arrhythmia via Regulation of the Calcium/Calmodulin Dependent Kinase II Signaling Pathway

We investigated the effects of Wenxin Keli (WXKL) on the Calcium/Calmodulin dependent kinase II (CaMK II) signal transduction pathway with transverse aortic constriction (TAC) rats. Echocardiographic measurements were obtained 3 and 9 weeks after the surgery. Meanwhile, the action potentials (APDs) were recorded using the whole-cell patch clamp technique, and western blotting was used to assess components of the CaMK II signal transduction pathway. At both 3 and 9 weeks after treatment, the fractional shortening (FS%) increased in the WXKL group compared with the TAC group. The APD90 of the TAC group was longer than that of the Sham group and was markedly shortened by WXKL treatment. Western blotting results showed that the protein expressions of CaMK II, phospholamban (PLB), and ryanodine receptor 2 (RYR2) were not statistically significant among the different groups at both treatment time points. However, WXKL treatment decreased the protein level and phosphorylation of CaMK II (Thr-286) and increased the protein level and phosphorylation of PLB (Thr-17) and the phosphorylation of RYR2 (Ser-2814). WXKL also decreased the accumulation of type III collagen fibers. In conclusion, WXKL may improve cardiac function and inhibit the arrhythmia by regulating the CaMK II signal transduction pathway.

The Effects of Tai Chi Training in Patients with Heart Failure: A Systematic Review and Meta-Analysis

Heart Failure (HF) is associated with significantly high morbidity and mortality. We performed a meta-analysis and updated new evidences from randomized controlled trials (RCTs) to determine the effects of Tai Chi (TC) in patients with HF. Electronic literature search of Medline, PubMed, EMBASE, the Cochrane Library, China national knowledge infrastructure (CNKI), and Wan Fang Database was conducted from inception of their establishment until 2017. And we also searched Clinical Trials Registries (https://clinicaltrials.gov/ and www.controlled-trials.com) for on-going studies. A total of 11 trials with 656 patients were available for analysis. The results suggested that TC was associated with an obviously improved 6-min walk distance [6MWD, weighted mean difference (WMD) 65.29 m; 95% CI 32.55–98.04] and quality of life (Qol, WMD −11.52 points; 95% CI −16.5 to −6.98) and left ventricular ejection fraction (LVEF, WMD 9.94%; 95% CI 6.95 to 12.93). TC was shown to reduce serum B-type natriuretic peptide [BNP, standard mean difference (SMD) −1.08 pg/mL; 95% CI −1.91 to −0.26] and heart rate (HR, WMD −2.52 bpm; 95% CI −3.49 to −1.55). In summary, our meta-analysis demonstrated the clinical evidence about TC for HF is inconclusive. TC could improve 6MWD, Qol and LVEF in patients with HF and may reduce BNP and HR. However, there is a lack of evidence to support TC altering other important long-term clinical outcomes so far. Further larger and more sustainable RCTs are urgently needed to investigate the effects of TC.

Mitochondria and the Pathophysiological Mechanism of Atrial Fibrillation

Atrial fibrillation (AF) is the most common and significant cardiac arrhythmia in clinical practice, however the pathophysiological mechanism of AF has not been fully explained. At present, there are no available treatment options that can target the underlying pathophysiological processes of AF. Research on improving management strategies for AF can start with a further understanding of the changes of cells in AF. Mitochondria play central roles in the function of cardiac myocytes and many of the pathophysiological processes implicated in AF are relative to mitochondrial function, including formation of reactive oxygen species (ROS), calcium homeostasis, and alterations of oxygen consumption. The changes of levels of phosphocreatine, electron transfer chain proteins and differences in mitochondrial distribution further imply that mitochondria play a role in AF. Related studies of recent years are summarized, in order to elucidate the causal relationship between mitochondria and AF, and provide potential therapeutic target for the treatment and prevention of AF in clinical practice. In the article, we summarize the direct or indirect factors that affect mitochondria function and thus cause AF, including anticancer agents, surgery, gene, age, air pollution, oxidative stress, and β3-adrenoceptor (β3-AR). There is a close relationship between mitochondrial dysfunction and the occurrence of AF, which cannot be ignored, and further research in this area is needed.

Mechanisms and Treatments of Oxidative Stress in Atrial Fibrillation

Atrial fibrillation (AF) is a frequent cardiac arrhythmia. It is a common major cause of serious diseases and is an increasing health-care burden. AF is associated with an excess amount of reactive oxygen species. In this review, we summarize several possible reactive oxygen species pathways that induce AF based on atrial electrical and structural remodeling data. The sources and factors implicated in AF-related oxidative stress include NADPH oxidase activation, calcium overloading and mitochondrial damage, angiotensin system activation, nitric oxide synthase uncoupling, and xanthine oxidase activation-associated cardiovascular conditions. Scavenging oxidative stress markers and related substances are essential aspects of these molecular mechanisms, and may be a therapeutic target in AF.

Immediate/Early vs. Delayed Invasive Strategy for Patients with Non-ST-Segment Elevation Acute Coronary Syndromes: A Systematic Review and Meta-Analysis

Invasive coronary revascularization has been shown to improve prognoses in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS), but the optimal timing of intervention remains unclear. This meta-analysis is to evaluate the outcomes in immediate (<2 h), early (<24 h), and delayed invasive group and find out which is the optimal timing of intervention in NSTE-ACS patients. Studies were identified through electronic literature search of Medline, PubMed Central, Embase, the Cochrane Library, and CNKI. Data were extracted for populations, interventions, outcomes, and risk of bias. All-cause mortality was the pre-specified primary end point. The longest follow-up available in each study was chosen. The odds ratio (OR) with 95% CI was the effect measure. The fixed or random effect pooled measure was selected based on the heterogeneity test among studies. In the comparison between early and delayed intervention, we found that early intervention led to a statistical significant decrease in mortality rate (n = 6,624; OR 0.78, 95% CI: 0.61–0.99) and refractory ischemia (n = 6,127; OR 0.50, 95% CI: 0.40–0.62) and a non-significant decrease in myocardial infarction (MI), major bleeding and revascularization. In the analysis comparing immediate and delayed invasive approach, we found that immediate intervention significantly reduced major bleeding (n = 1,217; OR 0.46, 95% CI: 0.23–0.93) but led to a non-significant decrease in mortality rate, refractory ischemia and revascularization and a non-significant increase in MI. In conclusion, early invasive strategy may lead to a lower mortality rate and reduce the risk of refractory ischemia, while immediate invasive therapy shows a benefit in reducing the risk of major bleeding.

Comparative Effectiveness of Acupuncture and Antiarrhythmic Drugs for the Prevention of Cardiac Arrhythmias: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Introduction and Objectives: This study was designed to systematically evaluate the effectiveness of acupuncture treatment for arrhythmia compared to existing drug therapy. Methods: Randomized controlled trials (RCTs) were identified through searches of the MEDLINE, CNKI, Embase, and Cochrane databases (1970 through 2016) and hand searches of cross-references from original articles and reviews. Clinical trials that randomized arrhythmia patients to acupuncture therapy vs. conventional drugs, sham acupuncture, or bed rest were included for analysis. Results: A total of 13 trials with 797 patients met the criteria for analysis. The results of the meta-analysis showed no statistically significant difference between acupuncture and conventional treatment for paroxysmal supraventricular tachycardia (PSVT) (n = 203; RR, 1.18; 95% CI 0.78–1.79; I2 = 80%; P = 0.44). However, in the ventricular premature beat (VPB) group, it showed a significant benefit of acupuncture plus oral administration of anti-arrhythmic drug (AAD) on response rates compared with the oral administration of AAD (n = 286; RR, 1.15; 95% CI 1.05–1.27; I2 = 0%; P = 0.002). Finally, when compared with the sinus tachycardia (ST) cases without any treatment, acupuncture has benefited these patients (n = 120; MD, 18.80, 95% CI 12.68–24.92; I2 = 81%; P < 0.00001). Conclusions: In summary, our meta-analysis demonstrates that clinical efficacy of acupuncture is not less than AAD for PSVT. Furthermore, in sub-group analysis, acupuncture with or without AAD, shows a clear benefit in treating VPB and ST. However, more definitive RCTs are warranted to guide clinical practice.

The Role of Biologically Active Ingredients from Chinese Herbal Medicines in the Regulation of Autophagy in Treating Cardiovascular Diseases and Other Chronic Diseases

Autophagy, a highly conserved starvation response mechanism with both defensive and protective effects in eukaryotic cells, is a lysosome-mediated degradation process for non-essential or damaged cellular constituents. It plays an important role in the cell survival, differentiation and development to maintain homeostasis. Autophagy is involved in cardiovascular diseases, cerebrovascular diseases, and neurodegenerative diseases, as well as tumours. Thus, modulating autophagy may provide potential therapeutic strategies. Recently, many active components of Chinese herbal medicines (CHM) have been found to modulate autophagy in myocardial cells, cerebral vascular cells, endothelial cells and tumour cells. This paper reviews the advances in studies on the active components of CHM that modulating autophagy in treating cardiovascular diseases and other chronic diseases over the past five years.