👤 Beatrice Frigerio

Aortic valve sclerosis affects 30 % of individuals over 65 and is associated with coronary artery disease, with risk of progression to aortic stenosis. Endothelial dysfunction, mediated by oxidative stress, impaired nitric oxide (NO) signaling, inflammation, and lipoprotein deposition, plays a central role in disease initiation and progression. This study investigated whether a combination of bioactive compounds could counteract these mechanisms and support vascular health. The effects of curcuma longa, coenzyme Q10, black garlic, vitamin B1, and vitamin D3 were tested in vitro on aortic valve endothelial cells. Cell viability, reactive oxygen species (ROS), and NO levels were quantified by commercially available kits, while gene expression was analyzed by RNA sequencing. A 4-week prospective pilot clinical study in 10 healthy volunteers without cardiovascular disease evaluated endothelial function and arterial stiffness. The compounds reduced ROS production (>27 %; p < 0.05), enhanced endothelial viability (>33 %; p < 0.05; except curcuma and black garlic), and increased NO production (>6 %; p < 0.05; except black garlic). Beneficial effects were reflected in upregulation of anti-atherosclerotic (GIPR, +0.058 copies per million, CPM; p < 0.05), antioxidant (GADL1, +0.55 CPM; p < 0.001), and anti-inflammatory (IL12A, +0.17 CPM; p < 0.01) genes. Clinically, daily supplementation improved endothelial function in participants found to have pre-existing endothelial dysfunction (p = 0.0336), with 50 % achieving normal levels after 4 weeks, while all subjects exhibited reduced arterial stiffness (p = 0.0016) without hepatic toxicity. The oral supplementation of the combination of these bioactive compounds improved endothelial function and vascular health, particularly in individuals with endothelial dysfunction, offering potential therapeutic benefits for cardiovascular health. Show less

The impact of cholesteryl ester transfer protein (CETP) on atherosclerosis is highly debated. This study aimed to investigate the associations between plasma CETP or CETP genotypes and carotid intima-media thickness (cIMT) and the influence of high-density lipoprotein cholesterol (HDL-C) on these associations. Plasma CETP and HDL-C concentrations were measured in 552 subjects free of any pharmacological treatment from the IMPROVE cohort, which includes 3711 European subjects at high cardiovascular risk. CETP single-nucleotide polymorphisms (SNPs) and cIMT measures (cIMT Show less

Chronic exposure to elevated levels of glucose and fatty acids leads to dysfunction of pancreatic β-cells by mechanisms that are only partly understood. The transcription factor peroxisome proliferator-activated receptor α (PPARα) is an important regulator of genes involved in fatty acid metabolism and has been shown to protect against lipid-induced β-cell dysfunction. We and others have previously shown that expression of the PPARα gene in β-cells is rapidly repressed by glucose. Here we show that the PPARα gene is transcribed from five alternative transcription start sites, resulting in three alternative first exons that are spliced to exon 2. Expression of all PPARα transcripts is repressed by glucose both in insulinoma cells and in isolated pancreatic islets. The observation that the dynamics of glucose repression of PPARα transcription are very similar to those of glucose activation of target genes by the carbohydrate response element-binding protein (ChREBP) prompted us to investigate the potential role of ChREBP in the regulation of PPARα expression. We show that a constitutively active ChREBP lacking the N-terminal domain efficiently represses PPARα expression in insulinoma cells and in rodent and human islets. In addition, we demonstrate that siRNA-mediated knockdown of ChREBP abrogates glucose repression of PPARα expression as well as induction of well established ChREBP target genes in insulinoma cells. In conclusion, this work shows that ChREBP is a critical and direct mediator of glucose repression of PPARα gene expression in pancreatic β-cells, suggesting that ChREBP may be important for glucose suppression of the fatty acid oxidation capacity of β-cells. Show less