Project description:parental HEK293T were challenged with 1064 µg/cm2 calcium oxalate monohydrate (COM) or sodium oxalate (NaOx) 4mM or vehicle for 24 hours and DNA microarray was performed. We observed and selected two-fold upregulation of laminin, beta 3 (LAMB3), early growth response 1 (EGR1), gremlin 1, DAN family BMP antagonist, Ca++-dependent secretion activator 2, Ras association domain family member 3, interleukin 33 and bone morphogenetic protein 8a , and two-fold down-regulation of interleukin 37 and intercellular adhesion molecule 1 in COM lord compared to vhicle.
Project description:Kidney stones (KS) are very common, excruciating, and are associated with tremendous healthcare cost, chronic kidney disease (CKD), and end stage renal disease (ESRD). Most KS are composed of calcium oxalate and very small increases in urine oxalate concentration increase the risk for stone formation. Besides its critical role in the pathogenesis of KS, emerging data suggest that disturbed oxalate homeostasis (hyperoxaluria and/or hyperoxalemia) contributes to CKD progression, CKD - and ESRD-associated cardiovascular diseases, progression of cyst growth in autosomal dominant polycystic kidney disease (ADPKD), and delayed graft function & poor renal allograft survival. This emphasizes the urgent need for plasma and urinary oxalate lowering therapies, and enhancing the bowel’s ability to secrete oxalate may effectively do so. We previously identified Oxalobacter formigenes (O. formigenes)-derived factors secreted in its culture conditioned medium (CM) which stimulated oxalate transport by human intestinal Caco2-BBE (C2) cells and reduced urinary oxalate excretion in hyperoxaluric mice by enhancing colonic oxalate secretion. Given their remarkable therapeutic potential, we now identified several proteins belonging to Sel1-like family as the major O. formigenes-derived secreted factors, and we determined the crystal structures for six proteins to better understand their function. Importantly, Sel1-14-derived small peptides P8 & P9 were identified as the major factors, with P8+9 closely recapitulate the CM’s effects, including acting through the oxalate transporters SLC26A2 & SLC26A6 and PKA activation. P8+9 also stimulate oxalate transport by human ileal and colonic organoids, confirming that these peptides work in human tissues. Collectively, the identification of these small peptides provide a great opportunity for developing a peptide-based novel therapeutic for hyperoxalemia, hyperoxaluria, and related disorders, impacting the outcomes of patients suffering from KS, primary hyperoxaluria, CKD, ADPKD, ESRD, and renal transplant recipients.
Project description:The present study aims to compare the miRNA expression profiles in exosomes derived from HK-2 cells treated with 0, 1, 2 mM sodium oxalate, and to explore the roles of different exosomal-miRNAs in the regulation of calcium oxalate (CaOx) stones formation.
Project description:Metabolic dysfunction-associated steatohepatitis (MASH) is on the rise, and with limited pharmacological therapy available, identification of new metabolic targets is urgently needed. Oxalate is a terminal metabolite produced from glyoxylate by lactate dehydrogenase (LDHA). The liver-specific alanine-glyoxylate aminotransferase (AGXT) detoxifies glyoxylate, preventing oxalate accumulation. We report that AGXT is suppressed and LDHA is activated in livers from patients and mice with MASH, leading to oxalate overproduction. In turn, oxalate promotes steatosis in hepatocytes by inhibiting peroxisome proliferator activated receptor-alpha (PPARα) transcription and fatty acid β-oxidation (FAO), and induces monocyte chemotaxis via C-C motif chemokine ligand 2. In male mice with diet-induced MASH, blocking oxalate overproduction through hepatocyte-specific AGXT overexpression or pharmacological inhibition of LDHA potently lower steatosis, inflammation, and fibrosis by inducing PPARα-driven FAO, and suppressing monocyte chemotaxis, nuclear factor-kappaB and transforming growth factor-beta targets. These findings highlight hepatic oxalate overproduction as a new target for the treatment of MASH.
Project description:The present study aims to assess the potential changes in LncRNAs of proximal renal cells in response to the adhesion of calcium oxalate monohydrate (COM) crystals. lncRNA microarray were applied to evaluate the expression of HK-2 cells exposed to COM crystal for 0 and 24 hours.
Project description:The present study aims to assess the potential changes in microRNAs of proximal renal tubular cells in response to the adhesion of calcium oxalate monohydrate (COM) crystals. microRNA microarray was applied to evaluate the expression of HK-2 cells exposed to COM crystals for 0 and 24 hours.