Evaluation of Incidence and Risk Factors of Sudden Cardiac Death in Patients with Chronic Coronary Syndrome Attending Physical Training

Abstract Introduction Regular physical activity is recommended to patients with chronic coronary syndrome (CCS). However, vigorous physical exercise occurs as a risk factor of sudden cardiac death (SCD). The effect of short-term and irregular exercise is controversial. The aim of this research is to assess the role of regular training in the incidence of SCD and to identify risk factors among patients with CCS participating in a long-term training program. Methods Data of risk factors, therapy, and participation were collected retrospectively for a 10-year period, assessing the length and regularity of participation. The incidence of SCD and related mortality was registered. ANOVA, χ 2 test, and multinominal logistic regression and stepwise analysis were performed. Results The Incidence of chronic kidney disease (CKD) was higher (p < 0.01) and taking beta-blockers (BBs) was lower (p = 0.04) in the SCD group. Irregular training, lack of BBs, smoking, and CKD increased the risk of SCD, while female sex, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers (ACEI/ARBs), and BBs decreased the risk of SCD. Conclusions Taking ACEI/ARBs and BBs proved to be a protective factor, emphasizing the use of optimal medical therapy. Assessment of cardiac risk factors and control of comorbidities also proved to be important. The occurrence of SCD was connected to irregular physical activity, probably relating to the adverse effects of ad hoc exercising

ABCC1 polymorphisms in anthracycline-induced cardiotoxicity in childhood acute lymphoblastic leukaemia

Anthracyclines are potent cytostatic drugs the correct dosage of which is critical to aviod possible cardiac side effects. ABCC1 (MRP1) is expressed in the heart and takes part in the detoxification and protection of the cells from toxic effects of xenobiotics, including anthracyclines. Our objective was to search for associations between left ventricular function and single nucleotide polymorphisms of the ABCC1 gene in children who received anthracycline chemotherapy. We analyzed data of 235 pediatric patients with acute lymphoblastic leukemia. Patients were followed up by echocardiography (median follow up 6.3 years). Nine polymorphisms in the ABCC1 gene were genotyped. The ABCC1 rs3743527TT genotype and rs3743527TT-rs246221TC/TT genotype combination were found to be associated with lower left ventricular fractional shortening (LVFS) after chemotherapy. Our results suggest that genetic variants in the ABCC1 gene could influence anthracycline induced left ventricular dysfunction

Hyposialylated IgG activates endothelial IgG receptor FcγRIIB to promote obesity-induced insulin resistance.

Type 2 diabetes mellitus (T2DM) is a common complication of obesity. Here, we have shown that activation of the IgG receptor FcγRIIB in endothelium by hyposialylated IgG plays an important role in obesity-induced insulin resistance. Despite becoming obese on a high-fat diet (HFD), mice lacking FcγRIIB globally or selectively in endothelium were protected from insulin resistance as a result of the preservation of insulin delivery to skeletal muscle and resulting maintenance of muscle glucose disposal. IgG transfer in IgG-deficient mice implicated IgG as the pathogenetic ligand for endothelial FcγRIIB in obesity-induced insulin resistance. Moreover, IgG transferred from patients with T2DM but not from metabolically healthy subjects caused insulin resistance in IgG-deficient mice via FcγRIIB, indicating that similar processes may be operative in T2DM in humans. Mechanistically, the activation of FcγRIIB by IgG from obese mice impaired endothelial cell insulin transcytosis in culture and in vivo. These effects were attributed to hyposialylation of the Fc glycan, and IgG from T2DM patients was also hyposialylated. In HFD-fed mice, supplementation with the sialic acid precursor N-acetyl-D-mannosamine restored IgG sialylation and preserved insulin sensitivity without affecting weight gain. Thus, IgG sialylation and endothelial FcγRIIB may represent promising therapeutic targets to sever the link between obesity and T2DM

Hyposialylated IgG activates endothelial IgG receptor FcγRIIB to promote obesity-induced insulin resistance

Type 2 diabetes mellitus (T2DM) is a common complication of obesity. Here, we have shown that activation of the IgG receptor FcγRIIB in endothelium by hyposialylated IgG plays an important role in obesity-induced insulin resistance. Despite becoming obese on a high-fat diet (HFD), mice lacking FcγRIIB globally or selectively in endothelium were protected from insulin resistance as a result of the preservation of insulin delivery to skeletal muscle and resulting maintenance of muscle glucose disposal. IgG transfer in IgG-deficient mice implicated IgG as the pathogenetic ligand for endothelial FcγRIIB in obesity-induced insulin resistance. Moreover, IgG transferred from patients with T2DM but not from metabolically healthy subjects caused insulin resistance in IgG-deficient mice via FcγRIIB, indicating that similar processes may be operative in T2DM in humans. Mechanistically, the activation of FcγRIIB by IgG from obese mice impaired endothelial cell insulin transcytosis in culture and in vivo. These effects were attributed to hyposialylation of the Fc glycan, and IgG from T2DM patients was also hyposialylated. In HFD-fed mice, supplementation with the sialic acid precursor N-acetyl-D-mannosamine restored IgG sialylation and preserved insulin sensitivity without affecting weight gain. Thus, IgG sialylation and endothelial FcγRIIB may represent promising therapeutic targets to sever the link between obesity and T2DM