Emerging evidence indicates that alteration of gut microbiota plays an important role in chronic kidney disease (CKD)-related vascular calcification (VC). We aimed to investigate the specific gut microbiota and the underlying mechanism involved in CKD-VC. We identified an increased abundance of Prevotella copri (P. copri) in the feces of CKD rats (induced by using 5/6 nephrectomy followed by a high calcium and phosphate diet) with aortic calcification via amplicon sequencing of 16S rRNA genes. In patients with CKD, we further confirmed a positive correlation between abundance of P. copri and aortic calcification scores. Moreover, oral administration of live P. copri aggravated CKD-related VC and osteogenic differentiation of vascular smooth muscle cells in vivo, accompanied by intestinal destruction, enhanced expression of Toll-like receptor-4 (TLR4), and elevated lipopolysaccharide (LPS) levels. In vitro and ex vivo experiments consistently demonstrated that P. copri-derived LPS (Pc-LPS) accelerated high phosphate-induced VC and VSMC osteogenic differentiation. Mechanistically, Pc-LPS bound to TLR4, then activated the nuclear factor κB (NF-κB) and nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome signals during VC. Inhibition of NF-κB reduced NLRP3 inflammasome and attenuated Pc-LPS-induced VSMC calcification. Our study clarifies a novel role of P. copri in CKD-related VC, by the mechanisms involving increased inflammation-regulating metabolites including Pc-LPS, and activation of the NF-κB/NLRP3 signaling pathway. These findings highlight P. copri and its-derived LPS as potential therapeutic targets for VC in CKD.

BACKGROUND: Intraindividual variability in lipid profiles is recognized as a potential predictor of cardiovascular events. However, the influence of early adulthood lipid profile variability along with mean lipid levels on future coronary artery calcium (CAC) incidence remains unclear. METHODS: A total of 2395 participants (41.6% men; mean±SD age, 40.2±3.6 years) with initial CAC =0 from the CARDIA study (Coronary Artery Risk Development in Young Adults) were included. Serial lipid measurements were obtained to calculate mean levels and variability of total cholesterol, low-density lipoprotein cholesterol (LDL-C), non–high-density lipoprotein cholesterol (non-HDL-C), and triglycerides. CAC incidence was defined as CAC >0 at follow-up. RESULTS: During a mean follow-up of 9.0 years, 534 individuals (22.3%) exhibited CAC incidence. Higher mean levels of total cholesterol, LDL-C, and non-HDL-C were associated with a greater risk of future CAC incidence. Similarly, 1-SD increment of lipid variability, as assessed by variability independent of the mean, was associated with an increased risk of CAC incidence (LDL-C: hazard ratio, 1.139 [95% CI, 1.048–1.238]; P =0.002; non-HDL-C: hazard ratio, 1.102 [95% CI, 1.014–1.198]; P =0.022; and triglycerides: hazard ratio, 1.480 [95% CI, 1.384–1.582]; P <0.001). Combination analyses demonstrated that participants with both high lipid levels and high variability in lipid profiles (LDL-C and non-HDL-C) faced the greatest risk of CAC incidence. Specifically, elevated variability of LDL-C was associated with an additional risk of CAC incidence even in low mean levels of LDL-C (hazard ratio, 1.396 [95% CI, 1.106–1.763]; P =0.005). These findings remained robust across a series of sensitivity and subgroup analyses. CONCLUSIONS: Elevated variability in LDL-C and non-HDL-C during young adulthood was associated with an increased risk of CAC incidence in midlife, especially among those with high mean levels of atherogenic lipoproteins. These findings highlight the importance of maintaining consistently low levels of atherogenic lipids throughout early adulthood to reduce subclinical atherosclerosis in midlife. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00005130.

Background: Non-alcoholic fatty liver disease (NAFLD) has emerged as a predominant driver of chronic liver disease globally and is associated with increased cardiovascular disease morbidity and mortality. However, the association between NAFLD and calcific aortic valve disease remains unclear. We aimed to prospectively investigate the association between NAFLD and incident aortic valve calcification (AVC), as well as its genetic relationship with incident calcific aortic valve stenosis (CAVS).Methods: A post hoc analysis was conducted on 4226 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) database. We employed the adjusted Cox models to assess the observational association between NAFLD and incident AVC. Additionally, we conducted two-sample Mendelian randomization (MR) analyses to investigate the genetic association between genetically predicted NAFLD and calcific aortic valve stenosis (CAVS), a severe form of CAVD. We repeated the MR analyses by excluding NAFLD susceptibility genes linked to impaired very low-density lipoprotein (VLDL) secretion.Results: After adjustment for potential risk factors, participants with NAFLD had a hazard ratio of 1.58 (95% CI: 1.03–2.43) for incident AVC compared to those without NAFLD. After excluding genes associated with impaired VLDL secretion, the MR analyses consistently showed the significant associations between genetically predicted NAFLD and CAVS for 3 traits: chronic elevation of alanine aminotransferase (odds ratio = 1.13 [95% CI: 1.01–1.25]), imaging-based NAFLD (odds ratio = 2.81 [95% CI: 1.66–4.76]), and biopsy-confirmed NAFLD (odds ratio = 1.12 [95% CI: 1.01–1.24]). However, the association became non-significant when considering all NAFLD susceptibility genes.Conclusions: NAFLD was independently associated with an elevated risk of incident AVC. Genetically predicted NAFLD was also associated with CAVS after excluding genetic variants related to impaired VLDL secretion.

Clinical and Molecular Hepatology