ß-sheets in serum protein are independent risk factors for coronary lesions besides LDL-C in coronary heart disease patients.

Background: Coronary heart disease (CHD) patients with standard low-density lipoprotein cholesterol (LDL-C) remain at risk of cardiovascular events, making it critical to explore new targets to reduce the residual risk. The relationship between ß-sheet conformation and CHD is gaining attention. This study was designed to compare the coronary lesions in CHD patients with varying LDL-C and evaluate whether serum ß-sheets are associated with coronary damage. Methods: Two hundred and one patients diagnosed with stable CHD were recruited and divided into four groups according to LDL-C. Baseline information, coronary lesion-related indicators, and peripheral blood samples were collected. Serum ß-sheet content was determined by thioflavin T fluorescence. Results: The baseline information was comparable in CHD patients with different LDL-C. No difference was found in indicators relevant to coronary lesions among groups. The content of ß-sheet was negatively correlated with LDL-C. Multiple linear regression revealed that serum ß-sheet was positively correlated with coronary lesion when risk factors such as age, smoking, and LDL-C were controlled. Conclusions: This is the first study that reports the serum ß-sheet levels of CHD patients being gradually increased with decreasing LDL-C when coronary lesions were comparable. Serum ß-sheet might exacerbate the coronary lesions in CHD patients independent of known risk factors such as LDL-C.

PGF2α-FP Receptor Ameliorates Senescence of VSMCs in Vascular Remodeling by Src/PAI-1 Signal Pathway.

Senescence in vascular smooth muscle cells (VSMCs) is involved in vascular remodeling of aged mice. ProstaglandinF2α- (PGF2α-) FP receptor plays a critical role in cardiovascular diseases (CVDs), hypertension, and cardiac fibrosis. However, its role in senescence-induced arteriosclerosis is yet to be fully elucidated. In this study, we found that FP receptor expression increased in aged mouse aortas and senescence VSMCs. FP receptor gene silencing can ameliorate vascular aging and inhibit oxidative stress, thereby reducing the expression of PAI-1, inhibiting the activation of MMPs, and ultimately improving the excessive deposition of ECM and delaying the process of vascular fibrosis. FP receptor could promote VSMC senescence by upregulated Src/PAI-1 signal pathway, and inhibited FP receptor/Src/PAI-1 pathway could ameliorate VSMCs aging in vitro, evidenced by the decrease of senescence-related proteins P16, P21, P53, and GLB1 expressions. These results suggested that FP receptor is a promoter of vascular aging, by inducing cellular aging, oxidative stress, and vascular remodeling via Src and PAI-1 upregulation.

Serum complement C1q level is associated with acute coronary syndrome.

BACKGROUND AND OBJECTIVES: The complement system plays an important role in the development of acute coronary syndrome (ACS). Complement C1q is an important initial component of the classical complement pathway and closely related to many chronic inflammatory diseases, including atherosclerosis (AS). We aimed to determine whether there was association between serum complement C1q and the severity of coronary stenosis. SUBJECTS AND METHODS: 320 patients who underwent coronary arteriography (CAG) were stratified into non-ACS group (control group, n = 74), unstable angina group (UA group, n = 197) and acute myocardial infarction group (AMI group, n = 49) according to the severity of coronary stenosis and clinical manifestations. The severity of coronary stenosis was represented in Gensini score, and serum complement C1q level was compared using immunity transmission turbidity among three groups. RESULTS: The level of complement C1q in AMI group was lower significantly than control group and UA group (P < 0.05), but there was no correlation between serum complement C1q and Gensini score (ß=-0.086, P = 0.125). In nitrate-taking patients, serum complement C1q had a negative association with Gensini score (r=-0.275, P = 0.001), and in non-smokers, there was also a negative correlation (ß=-0.159, P = 0.036). After calibrating smoking, drinking or statins, the serum complement C1q levels of control group, UA group and AMI group decreased in sequence (P <  0.05). Logistic regression analysis showed that the decreasing of serum complement C1q was an unfavorable factor for acute myocardial infarction (OR=0.984, 95 %CI=0.972∼0.997, P = 0.015) and for ACS (OR=0.984, 95 %CI=0.971∼0.984, P = 0.025) in drinking patients. Regrettably, ROC curve suggested that the accuracy in diagnosing coronary atherosclerotic heart disease by serum complement C1q was low (AUC=0.568, 95 %CI= 0.492-0.644, P = 0.076, sensitivity 73.6 %, specificity 58.1 %). CONCLUSION: Serum complement C1q in ACS patients, in particular AMI patients, showed lower level. This finding suggests further decrease of complement C1q level in ACS patients may be a contributory factor to instability or rupture of atherosclerotic plaques. Combined with other clinical indicators, it can be helpful to predict the risk and severity of coronary stenosis.

Sarcopenia is attenuated by TRB3 knockout in aging mice via the alleviation of atrophy and fibrosis of skeletal muscles.

BACKGROUND: Sarcopenia causes several adverse events in elderly people. Muscle fibre atrophy and interstitial fibrosis are the main histopathological changes in sarcopenia and account for decreased muscle function. Tribbles homologue 3 (TRB3) was previously reported to exhibit age-related expression and play a vital role in cell proliferation, differentiation, and fibrosis. We aimed to investigate how TRB3 affects sarcopenia. METHODS: Wild-type and TRB3 knockout C57/BL6J mice were randomly divided into young and old groups. Exercise capacity was evaluated, and single-muscle function was detected by electrophysiological techniques, after which the mice were sacrificed to collect their gastrocnemius muscles for assessment of atrophy and fibrosis by histopathological and molecular biological methods. TRB3 expression, autophagy level, and MAPK signalling pathway activity were evaluated through western blotting. The interaction of TRB3 with P62 and the association between TRB3 and the MAPK signalling pathway were detected by co-immunoprecipitation. RESULTS: In aged mice, exercise capacity and cross-sectional area of skeletal muscle fibres were decreased significantly, whereas TRB3, atrophy-related markers atrogin 1 and MuRF 1, and interstitial fibrosis, including collagen volume fraction, contents of collagens I and III, and ratio of collagens I to III, were increased significantly (P < 0.05 for all). Following TRB3 knockout, the cross-sectional area of muscle fibres, mainly fast fibres, was elevated (P < 0.05 for both), the atrogin 1 expression was decreased (P = 0.0163), and the corresponding tetanic force of fast muscles was increased (P = 0.0398). Conversely, interstitial fibrosis was substantially decreased and exercise capacity was significantly increased in the knockout mice. In terms of the underlying mechanisms, the autophagy receptor p62 was markedly increased and the MAPK signalling pathway was activated in aged skeletal muscles, which might be attributed to the interaction of TRB3 with p62 and MAPKKs, including MEK1/MEK2, MEK3/MEK6, and MEK4/MKK4. Notably, TRB3 knockout reduced the accumulation of p62 and LC3 (P < 0.05 for both), decreased the phosphorylation of JNK (P = 0.0015), and increased p38 phosphorylation (P = 0.0021). CONCLUSIONS: TRB3 knockout in mice attenuated muscle fibre atrophy and reduced skeletal muscle fibrosis by increasing autophagy and inhibiting the MAPK signalling pathway. Correspondingly, in aged knockout mice, exercise capacity was improved. Interfering with TRB3 expression in aged skeletal muscles may serve as a target for the prevention and treatment of age-related sarcopenia.

Impact of Perioperative Levosimendan Administration on Risk of Bleeding After Cardiac Surgery: A Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Levosimendan, a calcium sensitizer and potassium channel opener, has been demonstrated to improve myocardial function without increasing oxygen consumption and to show protective effects in other organs. Recently, a prospective, randomized controlled trial (RCT) revealed an association between levosimendan use and a possible increased risk of bleeding postoperatively. Levosimendan's anti-platelet effects have been shown in in vitro studies. Current studies do not provide sufficient data to support a relation between perioperative levosimendan administration and increased bleeding risk. PURPOSE: Our goal was to investigate the relation between perioperative levosimendan administration and increased bleeding risk using a meta-analysis study design. METHODS: The PubMed, Ovid, EMBASE and Cochrane Library databases were searched for relevant RCTs before July 1, 2019. The outcome parameters included reoperation secondary to increased bleeding in the postoperative period, the amount of postoperative recorded blood loss, and the need for transfusion of packed red blood cells (RBCs) and other blood products. RESULTS: A total of 1160 patients in nine RCTs (576 in the levosimendan group and 584 in the control group) were included according to our inclusion criteria. Analysis showed that perioperative levosimendan administration neither increased the rate of reoperation secondary to bleeding nor increased the amount of postoperative chest tube drainage when compared with the control group. In terms of blood product transfusion, levosimendan did not influence the requirement for RBC transfusion, platelet transfusion nor fresh frozen plasma (FFP) transfusion. Levosimendan also did not shorten or prolong the aortic cross-clamp time or the cardiopulmonary bypass time. CONCLUSION: The analyzed parameters, including reoperations due to bleeding, postoperative chest drainage and the requirement for blood products, revealed that levosimendan did not increase postoperative bleeding risk. More studies with a larger sample size are needed to address a more reliable conclusion due to study limitations.