The gut microbial metabolite trimethylamine N-oxide (TMAO) is increasingly regarded as a novel risk factor for cardiovascular events and mortality. However, little is known about the association between TMAO and hypertension. This meta-analysis was conducted to quantitatively assess the relation between the circulating TMAO concentration and hypertension prevalence. The PubMed, Cochrane Library, and Embase databases were systematically searched up to 17 June 2018. Studies recording the hypertension prevalence in members of a given population and their circulating TMAO concentrations were included. A total of 8 studies with 11,750 individuals and 6176 hypertensive cases were included in the analytic synthesis. Compared with low circulating TMAO concentrations, high TMAO concentrations were correlated with a higher prevalence of hypertension (RR: 1.12; 95% CI: 1.06, 1.17; P < 0.0001; I2 = 64%; P-heterogeneity = 0.007; random-effects model). Consistent results were obtained in all examined subgroups as well as in the sensitivity analysis. The RR for hypertension prevalence increased by 9% per 5-μmol/L increment (RR: 1.09; 95% CI: 1.05, 1.14; P < 0.0001) and 20% per 10-μmol/L increment of circulating TMAO concentration (RR: 1.20; 95% CI: 1.11, 1.30; P < 0.0001) according to the dose-response meta-analysis. To our knowledge, this is the first systematic review and meta-analysis demonstrating a significant positive dose-dependent association between circulating TMAO concentrations and hypertension risk.
Patients with peripheral artery disease (PAD) and diabetes compose a high-risk population for development of critical limb ischemia (CLI) and amputation, although the underlying mechanisms remain poorly understood. Comparison of dysregulated microRNAs from diabetic patients with PAD and diabetic mice with limb ischemia revealed the conserved microRNA, miR–130b-3p . In vitro angiogenic assays demonstrated that miR-130b rapidly promoted proliferation, migration, and sprouting in endothelial cells (ECs), whereas miR-130b inhibition exerted antiangiogenic effects. Local delivery of miR-130b mimics into ischemic muscles of diabetic mice ( db/db ) following femoral artery ligation (FAL) promoted revascularization by increasing angiogenesis and markedly improved limb necrosis and amputation. RNA-Seq and gene set enrichment analysis from miR-130b –overexpressing ECs revealed the BMP/TGF-β signaling pathway as one of the top dysregulated pathways. Accordingly, overlapping downregulated transcripts from RNA-Seq and miRNA prediction algorithms identified that miR-130b directly targeted and repressed the TGF-β superfamily member inhibin-β-A ( INHBA ). miR-130b overexpression or siRNA-mediated knockdown of INHBA induced IL-8 expression, a potent angiogenic chemokine. Lastly, ectopic delivery of silencer RNAs (siRNA) targeting Inhba in db/db ischemic muscles following FAL improved revascularization and limb necrosis, recapitulating the phenotype of miR-130b delivery. Taken together, a miR-130b / INHBA signaling axis may provide therapeutic targets for patients with PAD and diabetes at risk of developing CLI.
Piezoelectric nanomaterials that generate reactive oxygen species (ROS) through piezoelectric polarization under mechanical stimulation have emerged as a promising cancer therapy platform. However, their potential is limited by poor piezoresponse, low catalytic efficiency, and the exacerbation of immunosuppression due to ROS-induced release of tumor-derived exosomes. In this study, we employed a doping-engineered strategy by incorporating manganese ions (Mn2⁺) into hydroxyapatite (HAP) to enhance its piezocatalytic performance, while combining exosome inhibition to achieve a synergistic improvement in tumor therapy. Mn2⁺-doped HAP was synthesized via a one-pot hydrothermal method and subsequently modified with a ROS-cleavable lipid, DSPE-TK-mPEG. During the modification process, the exosome inhibitor GW4869 was loaded, resulting in the formation of GW4869-loaded Mn2⁺-HAP-Lipid nanocomposites (abbreviated as GMHL). The introduction of Mn2+ significantly reduced the bandgap of HAP, thereby enhancing its piezoelectric catalytic activity to generate ROS under ultrasound (US) stimulation, which triggered the cleavage of ketone-thiol bond in DSPE-TK-mPEG and led to the efficient release of GW4869. In multiple tumor models, GMHL effectively retard tumor growth and inhibited the production of tumor-derived exosomal PD-L1 upon US stimulation, thereby triggering an anticancer immune response through modulation of the immunosuppressive tumor microenvironment.