ApoA-I Infusion Therapies Following Acute Coronary Syndrome: Past, Present, and Future

Aqueous extract of fermented Eucommia ulmoides leaves alleviates hyperlipidemia by maintaining gut homeostasis and modulating metabolism in high-fat diet fed rats

BACKGROUND

As a traditional Chinese medicinal herb, the lipid-lowing biological potential of Eucommia ulmoides leaves (EL) has been demonstrated. After fermentation, the EL have been made into various products with lipid-lowering effects and antioxidant activity. However, the anti-hyperlipidemic mechanism of fermented Eucommia ulmoides leaves (FEL) is unclear now.

PURPOSE

To evaluate the effects of FEL on hyperlipidemia and investigate the mechanism based on regulating gut homeostasis and host metabolism.

METHODS

Hyperlipidemia animal model in Wistar rats was established after 8 weeks high-fat diet (HFD) fed. The administered doses of aqueous extract of FEL (FELE) were 128, 256 and 512 mg/kg/d, respectively. Serum biochemical parameters detection, histopathological sections analysis, 16S rDNA sequencing of gut microbiota and untargeted fecal metabolomics analysis, were performed to determine the therapeutic effects and predict related pathways of FELE on hyperlipidemia. The changes of proteins and genes elated to lipid were detected by Immunofluorescence (IF) and quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

56 Components in FELE were identified by UPLC-MS, with organic acids, flavonoids and phenolic acids accounting for the majority. The intervention of FELE significantly reduced the body weight, lipid accumulation and the levels of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein-cholesterol (LDL-C) in hyperlipidemia rats, while increased the level of High-density lipoprotein-cholesterol (HDL-C). Meanwhile, FELE improved the inflammatory makers and oxidative stress factors, which is tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT). These results demonstrated that FETE can effectively reduce blood lipids and alleviate inflammation and oxidative damage caused by hyperlipidemia. Mechanistically, FELE restore the homeostasis of gut microbiota by reducing the Firmicutes/Bacteroidetes ratio and increasing the abundance of probiotics, especially Lactobacillus, Rombousia, Bacteroides, Roseburia, Clostridia_UCG-014_Unclassified, while modulated metabolism through amino acid, bile acid and lipid-related metabolism pathways. In addition, the Pearson correlation analysis found that the upregulated bilirubin, threonine, dopamine and downregulated lipocholic acid, d-sphingosine were key metabolites after FELE intervention. IF and qRT-PCR analysis showed that FELE upregulated the expression of fatty acid oxidation proteins and genes (PPARα, CPT1A), bile acid synthesis and excretion proteins and genes (LXRα, CYP7A1, FXR), and downregulated the expression of adipogenic gene (SREBP-1c) by regulating gut microbiota to improve metabolism and exert a lipid-lowering effect.

CONCLUSION

This work filled the lipid-lowering mechanism gap of FEL. FELE can improve HFD-induced hyperlipidemia by regulating the gut microbiota homeostasis and metabolism. Thus, FEL has the potential to develop into the novel raw material of lipid-lowering drugs.

Targeting the vivid facets of apolipoproteins as a cardiovascular risk factor in rheumatoid arthritis

Mostly, cardiovascular diseases are blamed for casualties in rheumatoid arthritis (RA) patients. Customarily, dyslipidemia is probably the most prevalent underlying cause of untimely demise in people suffering from RA as it hastens the expansion of atherosclerosis. The engagement of inflammatory cytokines like tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), etc., is crucial in the progression and proliferation of both RA and abnormal lipid parameters. Thus, lipid abnormalities should be monitored frequently in patients with both primary and advanced RA stages. An advanced lipid profile examination, i.e., direct role of apolipoproteins associated with various lipid molecules is a more dependable approach for better understanding of the disease and selecting suitable therapeutic targets. Therefore, studying their apolipoproteins is more relevant than assessing RA patients' altered lipid profile levels. Among the various apolipoprotein classes, Apo A1 and Apo B are primarily being focused. In addition, it also addresses how calculating Apo B:Apo A1 ratio can aid in analyzing the disease's risk. The marketed therapies available to control lipid abnormalities are associated with many other risk factors. Hence, directly targeting Apo A1 and Apo B would provide a better and safer option.

High-Density Lipoproteins at the Interface between the NLRP3 Inflammasome and Myocardial Infarction

Despite significant therapeutic advancements, morbidity and mortality following myocardial infarction (MI) remain unacceptably high. This clinical challenge is primarily attributed to two significant factors: delayed reperfusion and the myocardial injury resulting from coronary reperfusion. Following reperfusion, there is a rapid intracellular pH shift, disruption of ionic balance, heightened oxidative stress, increased activity of proteolytic enzymes, initiation of inflammatory responses, and activation of several cell death pathways, encompassing apoptosis, necroptosis, and pyroptosis. The inflammatory cell death or pyroptosis encompasses the activation of the intracellular multiprotein complex known as the NLRP3 inflammasome. High-density lipoproteins (HDL) are endogenous particles whose components can either promote or mitigate the activation of the NLRP3 inflammasome. In this comprehensive review, we explore the role of inflammasome activation in the context of MI and provide a detailed analysis of how HDL can modulate this process.

Association of per- and polyfluoroalkyl substances with hepatic steatosis and metabolic dysfunction-associated fatty liver disease among patients with acute coronary syndrome

Etiology of hepatic steatosis and metabolic dysfunction-associated fatty liver disease (MAFLD) among acute coronary syndrome (ACS) remains unclear. Existing studies suggested the potential role of per- and polyfluoroalkyl substances (PFAS) in comorbidity of hepatic steatosis among ACS patients. Therefore, we conducted a cross-sectional study based on the ACS inpatients to assess the associations of plasma PFAS congeners and mixtures with hepatic steatosis and MAFLD. This study included 546 newly diagnosed ACS patients. Twelve PFAS were quantified using ultra-high-performance liquid chromatography-tandem mass spectrometry. Hepatic steatosis was defined by hepatic steatosis index (HSI). MAFLD was defined as the combination of hepatic steatosis based on the risk factor calculation with metabolic abnormalities. Generalized linear model was used to examine the associations of PFAS congeners with HSI and MAFLD. Adaptive elastic net (AENET) was further used for PFAS congeners selection. Mixture effects were also assessed with Bayesian kernel machine regression model (BKMR). Congeners analysis observed significant greater percent change of HSI for each doubling in PFOS (1.82%, 95% CI: 0.87%, 2.77%), PFHxS (1.17%, 95% CI: 0.46%, 1.89%) and total PFAS (1.84%, 95% CI: 0.56%, 3.14%). Moreover, each doubling in PFOS (OR=1.42, 95% CI: 1.13, 1.81), PFHxS (OR=1.31, 95% CI: 1.09, 1.59) and total PFAS (OR=1.43, 95% CI: 1.06, 1.94) was associated with increased risk of MAFLD. In AENET regression, only PFOS presented significant positive associations with HSI. Mixture analysis indicated significant positive associations between PFAS mixtures and HSI. This is the first study to demonstrate associations of PFAS congeners and mixtures with hepatic steatosis and MAFLD among ACS patients, which provides hypothesis into the mechanisms behind comorbidity of hepatic steatosis among ACS patients, as well as tertiary prevention of ACS.

The potential role and mechanism of circRNAs in foam cell formation

Atherosclerosis is a significant risk factor for coronary heart disease (CHD) and myocardial infarction (MI). Atherosclerosis develops during foam cell generation, which is caused by an imbalance in cholesterol uptake, esterification, and efflux. LOX-1, SR-A1, and CD36 all increased cholesterol uptake. ACAT1 and ACAT2 promote free cholesterol (FC) esterification to cholesteryl esters (CE). The hydrolysis of CE to FC was aided by nCEH. FC efflux was promoted by ABCA1, ABCG1, ADAM10, and apoA-I. SR-BI promotes not only cholesterol uptake but also FC efflux. Circular RNAs (circRNAs), which are single-stranded RNAs with a closed covalent circular structure, have emerged as promising biomarkers and therapeutic targets for atherosclerosis due to their highly tissue, cell, and disease state-specific expression profiles. Numerous studies have shown that circRNAs regulate foam cell formation, acting as miRNA sponges to influence atherosclerosis development by regulating the expression of SR-A1, CD36, ACAT2, ABCA1, ABCG1, ADAM10, apoA-I, SR-B1. Several circRNAs, including circ-Wdr91, circ 0004104, circRNA0044073, circRNA_0001805, circDENND1B, circRSF1, circ 0001445, and circRNA 102682, are potential biomarkers for atherosclerosis to better evaluate cardiovascular risk. It is difficult to deliver synthetic therapeutic circRNAs to the desired target tissues. Nanotechnology, such as GA-RM/GZ/PL, may be an important solution to this problem. In this review, we focus on the potential role and mechanism of circRNA/miRNA axis in foam cell formation in the hopes of discovering new targets for the diagnosis, prevention, and treatment of atherosclerosis.

Very low HDL levels: clinical assessment and management

In individuals with very low high-density lipoprotein (HDL-C) cholesterol, such as Tangier disease, LCAT deficiency, and familial hypoalphalipoproteinemia, there is an increased risk of premature atherosclerosis. However, analyzes based on comparisons of populations with small variations in HDL-C mediated by polygenic alterations do not confirm these findings, suggesting that there is an indirect association or heterogeneity in the pathophysiological mechanisms related to the reduction of HDL-C. Trials that evaluated some of the HDL functions demonstrate a more robust degree of association between the HDL system and atherosclerotic risk, but as they were not designed to modify lipoprotein functionality, there is insufficient data to establish a causal relationship. We currently have randomized clinical trials of therapies that increase HDL-C concentration by various mechanisms, and this HDL-C elevation has not independently demonstrated a reduction in the risk of cardiovascular events. Therefore, this evidence shows that (a) measuring HDL-C as a way of estimating HDL-related atheroprotective system function is insufficient and (b) we still do not know how to increase cardiovascular protection with therapies aimed at modifying HDL metabolism. This leads us to a greater effort to understand the mechanisms of molecular action and cellular interaction of HDL, completely abandoning the traditional view focused on the plasma concentration of HDL-C. In this review, we will detail this new understanding and the new horizon for using the HDL system to mitigate residual atherosclerotic risk.