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Lead exposure contributing to cardiovascular diseases is known and recognized widely. As the deleterious effects of low lead exposure attained increasing attention over the last decades, there have been numerous studies exploring the association of low levels of lead exposure and cardiovascular diseases. Moreover, it has been observed that lead exposure could cause telomere shortening and lipid disturbance, and that telomere shortening and lipid disturbance are closely related with cardiovascular diseases. Hence, telomere shortening and lipid disturbance might play an important role in the pathophysiological process of chronic low levels of lead exposure contributing to cardiovascular diseases. This review is intended to explore views of the rarely mentioned mechanism, telomere shortening and lipid disturbance, and the cardiovascular effects of low levels of lead exposure.

Introduction: The cardiovascular efficacy of glucagon-like peptide 1 receptor agonists (GLP-1RAs) in type 2 diabetes mellitus (T2DM) are well documented; however, the differences in cardiovascular efficacy among subpopulations remain unknown. This systematic review and meta-analysis aimed to explore the differences in cardiovascular efficacy of long-acting GLP-1RAs among subpopulations of patients with T2DM and to assess the drug safety. Methods: Relevant studies up to March 31, 2020 were searched for in six electronic databases, namely PubMed, Cochrane Library, Embase, Clinical Trials, Science Direct, and Web of Science. The primary outcome was three-point major adverse cardiovascular events (including cardiovascular mortality, non-fatal myocardial infarction, and non-fatal stroke). Subpopulations were defined using ten selected influential factors, and the differences in cardiovascular efficacy in subpopulations stratified by different influential factors were accessed by synthesizing studies with random-effects models one by one. Results: A total of six cardiovascular outcome trials of long-acting GLP-1RAs, comprising 49,936 participants, were included. Among stratified subpopulations, no significant differences in the cardiovascular efficacy of long-acting GLP-1RAs were observed across the ten characteristics of subjects (all P for interaction > 0.05). Favorable trends were observed in the subpopulation with established cardiovascular disease (CVD) compared to that without (P = 0.171). With regards to safety, long-acting GLP-1RAs did not significantly increase the risk of retinopathy (OR 1.09; 95% CI 0.92–1.29; P = 0.316), but increase the risk of serious gastrointestinal events (OR 1.37; 95% CI 1.02–1.83; P = 0.037). Long-acting GLP-1RAs did not significantly increase the risk of serious adverse events (OR 0.92; 95% CI 0.85–1.00; P = 0.039). Conclusions: Our analysis suggested no subpopulation differences in the cardiovascular efficacy of long-acting GLP-1RAs among stratified subpopulations, and favorable trends were only observed in the subpopulation with established CVD. These findings may have implications for the management of long-acting GLP-1RAs across subpopulations of patients with T2DM. [ABSTRACT FROM AUTHOR]

High density lipoprotein (HDL) cholesterol levels and cholesterol efflux capacity (CEC) are inversely correlated with coronary artery disease (CAD) risk. Myeloperoxidase (MPO) derived oxidants and HDL proteome changes are implicated in HDL dysfunction in subjects with CAD in the United States; however, the effect of MPO on HDL function and HDL proteome in ethnic Chinese population is unknown. We recruited four matched ethnic Chinese groups (20 patients each): subjects with 1) low HDL levels (HDL levels in men <40mg/dL and women <50mg/dL) and non-CAD (identified by coronary angiography or cardiac CT angiography); 2) low HDL and CAD; 3) high HDL (men >50mg/dL; women >60mg/dL) with no CAD; and 4) high HDL with CAD. Serum cytokines, serum MPO levels, serum CEC, MPO-oxidized HDL tyrosine moieties, and HDL proteome were assessed by mass spectrometry individually in the four groups. The cytokines, MPO levels, and HDL proteome profiles were not significantly different between the four groups. As expected, CEC was depressed in the entire CAD group but more specifically in the CAD low-HDL group. HDL of CAD subjects had significantly higher 3-nitrotyrosine than non-CAD subjects, but the MPO-specific 3-chlorotyrosine was unchanged; CEC in the CAD low-HDL group did not correlate with either HDL 3-chlorotyrosine or 3-nitrotyrosine levels. Neither 3-chlorotyrosine, which is MPO-specific, nor 3-nitrotyrosine generated from MPO or other reactive nitrogen species was associated with CEC. MPO mediated oxidative stress and HDL proteome composition changes are not the primary cause HDL dysfunction in Chinese subjects with CAD. These studies highlight ethnic differences in HDL dysfunction between United States and Chinese cohorts raising possibility of unique pathways of HDL dysfunction in this cohort. [ABSTRACT FROM AUTHOR]