Inflammation and oxidative stress are common features of patients with chronic kidney disease (CKD) and many uremic solutes retained in these patients could be involved in these processes, among which protein bound solutes such as indoxyl-sulfate. White adipose tissue recently gained attention as an important source of inflammation and oxidative stress. To examine the effect of indoxyl sulfate on adipocytes, 3T3-L1 adipose cells were incubated with indoxyl sulfate to mimic the conditions encountered in uremic patients. Incubation of adipose cells with indoxyl-sulfate increased reactive oxygen species (ROS) production generated mainly through activation of NADPH oxidase since it was prevented by the NADPH oxidase inhibitor apocynin. Exposure to indoxyl sulfate furthermore exacerbated the secretion of tumor necrosis factor-α and interleukin-6 by adipose cells. This inflammatory response was prevented by NADPH oxidase inhibition pinpointing the pivotal role of intracellular oxidative stress. Indoxyl ...

Flowers of Carthamus tinctorius L. are traditionally used in China to treat cerebrovascular and cardiovascular diseases. Hydroxysafflor yellow A (HSYA), the main constituent of Carthamus tinctorius L. flowers, is known for its multiple biological activities. In the present study, HSYA was isolated from Carthamus tinctorius L. flowers by a macroporous resin adsorption chromatography method coupled with a Waters high-throughput auto-purification system and it's vasodilatation effects on pulmonary artery (PA) were explored by an assay of tension study on rat pulmonary artery (PA) rings. Results suggest that HSYA possesses vascular relaxation effects on rat PA by activating the KV channel in pulmonary vascular smooth muscle cells (PVSMCs).

Background: DNA variants in APOL1 associate with kidney disease, but the pathophysiologic mechanisms remain incompletely understood. Model organisms lack the APOL1 gene, limiting the degree to which disease states can be recapitulated. Here we present single-cell RNA sequencing (scRNA-seq) of genome-edited human kidney organoids as a platform for profiling effects of APOL1 risk variants in diverse nephron cell types. Methods: We performed footprint-free CRISPR-Cas9 genome editing of human induced pluripotent stem cells (iPSCs) to knock in APOL1 high-risk G1 variants at the native genomic locus. iPSCs were differentiated into kidney organoids, treated with vehicle, IFN-γ, or the combination of IFN-γ and tunicamycin, and analyzed with scRNA-seq to profile cell-specific changes in differential gene expression patterns, compared with isogenic G0 controls. Results: Both G0 and G1 iPSCs differentiated into kidney organoids containing nephron-like structures with glomerular epithelial cells, proximal tubules, distal tubules, and endothelial cells. Organoids expressed detectable APOL1 only after exposure to IFN-γ. scRNA-seq revealed cell type–specific differences in G1 organoid response to APOL1 induction. Additional stress of tunicamycin exposure led to increased glomerular epithelial cell dedifferentiation in G1 organoids. Conclusions: Single-cell transcriptomic profiling of human genome-edited kidney organoids expressing APOL1 risk variants provides a novel platform for studying the pathophysiology of APOL1-mediated kidney disease.

Background: Nitrative stress is a characteristic feature of the pathology of human pulmonary arterial hypertension. However, the role of nitrative stress in the pathogenesis of obliterative vascular remodelling and severe pulmonary arterial hypertension remains largely unclear.Method: Our recently identified novel mouse model (Egln1^Tie2Cre, Egln1encoding prolyl hydroxylase 2 (PHD2)) has obliterative vascular remodelling and right heart failure, making it an excellent model to use in this study to examine the role of nitrative stress in obliterative vascular remodelling.Results: Nitrative stress was markedly elevated whereas endothelial caveolin-1 (Cav1) expression was suppressed in the lungs ofEgln1^Tie2Cremice. Treatment with a superoxide dismutase mimetic, manganese (III) tetrakis (1-methyl-4-pyridyl) porphyrin pentachloride or endothelialNos3knockdown using endothelial cell-targeted nanoparticle delivery of CRISPR–Cas9/guide RNA plasmid DNA inhibited obliterative pulmonary vascular remodelling and attenuated severe pulmonary hypertension inEgln1^Tie2Cremice. Genetic restoration of Cav1 expression inEgln1^Tie2Cremice normalised nitrative stress, reduced pulmonary hypertension and improved right heart function.Conclusion: These data suggest that suppression of Cav1 expression secondary to PHD2 deficiency augments nitrative stress through endothelial nitric oxide synthase activation, which contributes to obliterative vascular remodelling and severe pulmonary hypertension. Thus, a reactive oxygen/nitrogen species scavenger might have therapeutic potential for the inhibition of obliterative vascular remodelling and severe pulmonary arterial hypertension.