Project description:Kidney stone disease causes significant morbidity and increases health care utilization. In this dataset, we applied a single-nucleus assay to renal papila samples in order to charachterize the cellular and molecular niches in patients with calcium oxalate (CaOx) stone disease and healthy subjects. In addition to identifying cell types important in papillary physiology, we characterize collecting duct cell subtypes and an undifferentiated epithelial cell type that was more prevalent in stone patients. Despite the focal nature of mineral deposition in nephrolithiasis, we uncover a global injury signature characterized by immune activation, oxidative stress and extracellular matrix remodeling. We also identify the association of MMP7 and MMP9 expression with stone disease and mineral deposition, respectively. MMP7 and MMP9 are significantly increased in the urine of patients with CaOx stone disease, and their levels correlate with disease activity. Our results define the spatial molecular landscape and specific pathways contributing to stone-mediated injury in the human papilla and identify associated urinary biomarkers.
Project description:Clinical and animal studies have demonstrated the increasing evidence of oxidative stress in kidney stone disease. Recent findings have shown that the interactions between calcium oxalate (CaOx) crystals and renal tubular cells can promote many cellular events such as cell proliferation, cell death, cellular injury, mitochondrial dysfunction and inflammatory cascade. All of these cellular events are associated with oxidative stress and overproduction of free radicals and reactive oxygen species (ROS) such as superoxide and hydrogen peroxide in renal tubular cells. However, almost all of these references have shown that oxidative stress occurs after the causative crystals have been deposited in the kidney or exposed to renal tubular cells, whereas its primary role as the etiology remained unclear. In this study, we examined effects of oxidative modifications of urinary proteins on CaOx stone formation processes. Urinary proteins were modified by performic oxidation and the presence of oxidatively modified urinary proteins was verified, quantified and characterized by Oxyblot assay and tandem mass spectrometry (nanoLC-ESI-LTQ-Orbitrap-MS/MS). Subsequently, activities of oxidatively modified urinary proteins on CaOx stone formation processes were examined.
Project description:Calcium oxalate stones account for over 80% of urinary stones, while the molecular mechanism of its formation is still not completely elucidated. The incidence of hyperoxaluria in calcium oxalate stone formation ranks only second to hypercalciuria. It plays an important role in the pathophysiological process of stone formation. We analyzed miRNA expression profiles between experimental hyperoxaluric rats and normal rats in order to find out the target genes and signaling pathways in the pathogenesis of hyperoxaluria.
Project description:Comparison between renal papilla tissue with and without the presence of calcified Randall’s plaques, and between the papilla, medulla, and cortex regions from within a single recurrent stone forming kidney demonstrated that patterns of gene expression between the papilla, medulla, and cortex that distinguished these three regions from one another. Disease and function analysis of these gene sets demonstrated up-regulation of genes related to urinary/renal disorders, granulocyte response, vascular smooth muscle cell proliferation, dehydration, and renal calcification and down-regulation of genes related to carboxylic acid/ lipid/ fatty acid transport and urine osmolality.
Project description:We found that mainstream cigarette smoking (4 cigarettes/day, 5 days/week for 2 weeks using Kentucky Research Cigarettes 3R4F) resulted in >20% decrease in the percentage of normal Paneth cell population in Atg16l1 T300A mice but showed minimal effect in wildtype littermate control mice, indicating that Atg16l1 T300A polymorphism confers sensitivity to cigarette smoking-induced Paneth cell damage. We performed 16S rRNA sequencing to identify potential microbiota changes associated with Paneth cell defect in Atg16l1 T300A mice exposed to cigarette smoking. Female mice were used at 4-5 weeks of age. Cigarette smoking was performed using smoking chamber with the dosage and schedule as described above. The fecal samples from the mice were collected for 16S rRNA sequencing analysis after completing 6 weeks of smoking.