Project description:Chronic kidney disease (CKD) accelerates vascular calcification (VC) via phenotypic switching of vascular smooth muscle cells (VSMCs). We investigated the roles of circulating small extracellular vesicles (sEVs) between the kidneys and VSMCs and uncovered relevant sEV-propagated microRNAs (miRNAs) and their biological signaling pathways. We established CKD models in rats and mice by adenine-induced tubulointerstitial fibrosis. The miRNA transcriptome of sEVs revealed a depletion of several miRNAs in CKD. Their expression levels in sEVs from CKD patients were correlated to kidney function. This study revealed the transcriptomic landscape of miRNAs propagated in sEVs in CKD. We investigated the therapeutic potential of miRNAs in VC.
Project description:Hyponatremia, one of the most frequently observed electrolyte disorders in patients with chronic kidney disease (CKD), is associated with increased mortality. Lower sodium concentrations or low osmolar conditions are shown to induce cell damages via apoptosis and oxidative stress, both of accelerate vascular calcification (VC), a critical phenotype of CKD patients. It is unknown whether hyponatremia or low osmolar condition plays roles in the pathogenesis of VC.Human vascular smooth muscle cells (VSMCs) were cultured with calcifying medium, which was supplemented high calcium and phosphate. Concentrations of sodium in the culture media were further modified to determine the impacts of osmotic pressure on VC. Microarray analysis of VSMCs revealed low osmolality activated Rac1-Akt pathway and reduced expression of NCX1, which is calcium-sodium exchanger.Lower osmolality including hyponatremic condition promotes high-phosphate-induced VC through multiple cellular processes including Rac1-Akt pathway activation.
Project description:Chronic kidney disease (CKD) is associated with increased cardiovascular risk, morphologically characterized by vascular calcification (VC). In CKD, high serum phosphate levels result in enhanced calcification propensity and the formation of circulating crystalline nanoaggregates (calciprotein particles, CPP2) containing calcium, phosphate and serum proteins. CPP2 can induce VC directly and this is recapitulated in vascular smooth muscle cells (VSMCs) in vitro. Under physiological conditions, vascular endothelial cells (ECs), rather than VSMCs are primarily exposed to circulating CPP2. Knowledge on the modulating effects of ECs on VC development is still in its infancy. The aim of this study was to investigate the paracrine signaling between ECs and VSMCs in CPP2-induced VC. To identify secreted soluble factors for CPP2-activated ECsthis factor, CPP2-activated ECs secretome was analyzed using mass spectrometry (LC/MS).
Project description:Chronic kidney disease (CKD) is associated with increased cardiovascular risk, morphologically characterized by vascular calcification (VC). In CKD, high serum phosphate levels result in enhanced calcification propensity and the formation of circulating crystalline nanoaggregates (calciprotein particles, CPP2) containing calcium, phosphate and serum proteins. CPP2 can induce VC directly and this is recapitulated in vascular smooth muscle cells (VSMCs) in vitro. Under physiological conditions, vascular endothelial cells (ECs), rather than VSMCs are primarily exposed to circulating CPP2. Knowledge on the modulating effects of ECs on VC development is still in its infancy. The aim of this study was to investigate the calcium and bioenergetics signaling in CPP2-induced EC, including using ECs global proteome.
Project description:During angiosperm male gametogenesis, microspores divide to produce a vegetative cell (VC) and a male germline (MG), each with a distinct cell fate. How the MG cell/VC fate is determined remains largely unknown. Here, we report that the VC-targeted H3K27me3 erasure resulted in VC fate transition towards a gamete destination. Multi-omics and cytologic analysis reveal that H3K27me3 is essential for VC fate commitment and contributes to suppress the MG cell fate initiation in VC, whereas MG cells require H3K27me3 reprograming for the gamete cell fate. This work suggests that the MG cell/VC fate is epigenetically regulated. The dimorphic H3K27 methylation acts as a core switch to determine their distinct cell fates and ensure the functional specification of both VC and MG for pollen fertility. This work also provides direct evidences for the proposal that VC maintains the default developmental program of microspore, whereas MG requires reprogramming.
Project description:During angiosperm male gametogenesis, microspores divide to produce a vegetative cell (VC) and a male germline (MG), each with a distinct cell fate. How the MG cell/VC fate is determined remains largely unknown. Here, we report that the VC-targeted H3K27me3 erasure resulted in VC fate transition towards a gamete destination. Multi-omics and cytologic analysis reveal that H3K27me3 is essential for VC fate commitment and contributes to suppress the MG cell fate initiation in VC, whereas MG cells require H3K27me3 reprograming for the gamete cell fate. This work suggests that the MG cell/VC fate is epigenetically regulated. The dimorphic H3K27 methylation acts as a core switch to determine their distinct cell fates and ensure the functional specification of both VC and MG for pollen fertility. This work also provides direct evidences for the proposal that VC maintains the default developmental program of microspore, whereas MG requires reprogramming.
Project description:Inflammation plays a crucial role in the development of acute kidney injury (AKI) and subsequent chronic kidney disease (CKD) following renal ischemia-reperfusion (IR). It has been demonstrated that metabolites from the gut microbiota can trigger inflammatory responses and modulate renal damage induced by IR. However, the exact driving factors and underlying mechanisms of this process remain unclear. Trimethylamine N-oxide (TMAO), a choline metabolite derived from the gut, has been observed to increase in AKI and CKD patients. Our study reveals that glycyrrhizic acid (GA) exacerbates IR-induced AKI and subsequent CKD through TMAO. To delve into the underlying mechanisms, we employed single-cell sequencing to construct a molecular map of kidney cells.