Gefapixant,a Novel P2X3 Antagonist,Protects against Post Myocardial Infarction Cardiac Dysfunction and Remodeling Via Suppressing NLRP3 Inflammasome

Objective The ATP responsive P2 purinergic receptors can be subdivided into metabotropic P2X family and ionotropic P2Y family.Among these,P2X3 is a type of P2X receptor which is specifically expressed on nerves,especially on pre-ganglionic sensory fibers.This study investigates whether gefapixant possesses the potential of inhibiting cardiac sympathetic hypersensitivity to protect against cardiac remodeling in the context of myocardial infarction.Methods The Sprague-Dawley rats were divided randomly into three groups:sham group-myocardial infarction group,and myocardial infarction with gefapixant treatment group.Myocardial infarction was induced by left anterior descending branch ligation.The gefapixant solution was intraperitoneally injected each time per day for 7 days and the appropriate dosage of gefapixant was determined according to the results of hematoxylin-eosin(HE)staining and myocardial injury biomarkers.Conditions of cardiac function were assessed by echocardiograph and cardiac fibrosis was evaluated by Western blotting and immunofluorescence staining of collagen I and collagen III.The sympathetic innervation was detected by norepinephrine concentration(pg/mL),in-vivo electrophysiology,and typical sympathetic biomarkers.Inflammatory cell infiltration was shown from immunofluorescence staining and pro-inflammatory signaling pathway activation was checked by immunohistology,quantitative realtime PCR(qPCR)and Western blotting.Results It was found that gefapixant injection of 10 mg/kg per day had the highest dosage-efficacy ratio.Furthermore,gefapixant treatment improved cardiac pump function as shown by increased LVEF and LVFS,and decreased LVIDd and LVIDs.The expression levels of collagen I and collagen III,and TNF-αwere all decreased by P2X3 inhibition.Mechanistically,the decreased activation of nucleotide-binding and oligomerization domain-like receptors family pyrin-domain-containing 3(NLRP3)inflammasome and subsequent cleavage of caspase-1 which modulated interleukin-1β(IL-1β)and IL-18 level in heart after gefapixant treatment were associated with the suppressed cardiac inflammation.Conclusion It is suggested that P2X3 inhibition by gefapixant ameliorates post-infarct autonomic nervous imbalance,cardiac dysfunction,and remodeling possibly via inactivating NLRP3 inflammasome.

Effects of Traditional Chinese Medicine Shensong Yangxin Capsules on Heart Rhythm and Function in Congestive Heart Failure Patients with Frequent Ventricular Premature Complexes：A Randomized, Double-blind, Multicenter Clinical Trial

Background：Pharmacological therapy for congestive heart failure （CHF） with ventricular arrhythmia is limited.In the study,our aim was to evaluate the effects of Chinese traditional medicine Shensong Yangxin capsules （SSYX） on heart rhythm and function in CHF patients with frequent ventricular premature complexes （VPCs）.Methods：This double-blind,placebo-controlled,multicenter study randomized 465 CHF patients with frequent VPCs to the SSYX （n =232） and placebo groups （n =233） for 12 weeks of treatment.The primary endpoint was the VPCs monitored by a 24-h ambulatory electrocardiogram.The secondary endpoints included the left ventricular ejection fraction （LVEF）,left ventricular end-diastolic diameter,N-terminal pro-brain natriuretic peptide （NT-proBNP）,New York Heart Association （NYHA） classification,6-min walking distance （6MWD）,Minnesota Living with Heart Failure Questionnaire （MLHFQ） scores,and composite cardiac events （CCEs）.Results：The clinical characteristics were similar at baseline.SSYX caused a significantly greater decline in the total number of VPCs than the placebo did （-2145 ± 2848 vs.-841 ± 3411,P 〈 0.05）.The secondary endpoints of the LVEE NYHA classification,NT-proBNP,6MWD,and MLHFQ scores showed a greater improvements in the SSYX group than in the placebo group （ALVEF at 12th week：4.75 ± 7.13 vs.3.30 ± 6.53;NYHA improvement rate at the 8th and 12th week：32.6% vs.21.8%,40.5% vs.25.7%;mean level of NT-proBNP in patients with NT-proBNP 〉125 pg/ml at 12th week：-122 [Q1,Q3：-524,0] vs.-75 [Q1,Q3：-245,0];A6MWD at 12th week：35.1 ± 38.6 vs.17.2 ± 45.6;AMLHFQ at the 4th,8th,and 12th week：-4.24 ± 6.15 vs.-2.31 ± 6.96,-8.l 9 ± 8.41 vs.-3.25 ± 9.40,10.60 ± 9.41 vs.-4.83 ± 11.23,all P 〈 0.05）.CCEs were not different between the groups during the study period.Conclusions：In this 12-week pilot study,SSYX was demonstrated to have the benefits of VPCs suppression and cardiac function improvement with good compliance on a background of standard treatment for CHF.

Effect of Shensong Yangxin on the Progression of Paroxysmal Atrial Fibrillation is Correlated with Regulation of Autonomic Nerve Activity

Background： Shensong Yangxin （SSYX）, a traditional Chinese herbal medicine, has long been used clinically to treat arrhythmias in China. However, the mechanism of SSYX on atrial fibrillation （AF） is unknown. In this study, we tested the hypothesis that the effect of SSYX on the progression of paroxysmal AF is correlated with the regulation of autonomic nerve activity. Methods： Eighteen mongrel dogs were randomly divided into control group （n = 6）, pacing group （n = 6）, and pacing ＋ SSYX group （n = 6）. The control group was implanted with pacemakers without pacing; the pacing group was implanted with pacemakers with long-term intermittent atrial pacing; the pacing ＋ SSYX group underwent long-term intermittent atrial pacing and SSYX oral administration. Results： Compared to the pacing group, the parameters of heart rate variability were lower after 8 weeks in the pacing ＋ SSYX group （low-frequency [LF] component： 20.85± 3.14 vs. 15.3±1.89 ms2, P =0.004; LF component/high-frequency component： 1.34 ± 0.33 vs. 0.77± 0.15, P 〈 0.001 ）. The atrial effective refractory period （AERP） was shorter and the dispersion of the AERP was higher after 8 weeks in the pacing group, while the changes were suppressed by SSYX intake. The dogs in the pacing group had more episodes and longer durations of AF than that in the pacing ＋ SSYX group. SSYX markedly inhibited the increase in sympathetic nerves and upregulation of tumor necrosis factor-alpha and interleukin-6 expression in the pacing ＋ SSYX group. Furthermore, SSYX suppressed the decrease of acetylcholine and α7 nicotinic acetylcholine receptor protein induced by long-term intermittent atrial pacing. Conclusions： SSYX substantially prevents atrial electrical remodeling and the progression of AF. These effects of SSYX may have association with regulating the imbalance of autonomic nerve activity and the cholinergic anti-inflammatory pathway.

Contemporary characteristics,management,and outcomes of patients hospitalized for atrial fibrillation in China:results from the real-world study of Chinese atrial fibrillation registry

Atrial fibrillation(AF)is a growing public health problem in the context of the epidemiologic transition from communicable to non-communicable diseases,and a high prevalence of AF was found in Chinese patients who died in hospital.[1]Indeed,most understanding of AF is based on findings from clinical trials and observational studies performed in North America and Western Europe,[2]and some studies have described the characteristics of patients with AF in other regions.These data have highlighted the important differences in the clinical characteristics and treatment of patients with AF in these regions.[3,4]However,few studies have investigated the characteristics of patients with AF in China.Hence,the aim of this study was to investigate the clinical demographics,management,and outcomes of patients hospitalized for AF using data from a recently registered AF-specific nationwide cohort study in China,the real-world study of Chinese atrial fibrillation(RWS-CAF)registry.The RWS-CAF registry(registration number:ChiCTR1900021250)comprises a multicenter,observational,prospective cohort that includes consecutive patients requiring hospitalization with a diagnosis of AF made according to the Chinese AF guidelines,spanning from November 1,2017,to October 31,2018.All of the enrolled hospitals are grade A class three hospitals.Individual patients hospitalized with AF who were aged 18 years or older were recruited.