Interaction between submicron COD crystals and renal epithelial cells

Abstract

Objectives: This study aims to investigate the adhesion characteristics between submicron calcium oxalate dihydrate (COD) with a size of 150 ± 50 nm and African green monkey kidney epithelial cells (Vero cells) before and after damage, and to discuss the mechanism of kidney stone formation. Methods: Vero cells were oxidatively injured by hydrogen peroxide to establish a model of injured cells. Scanning electron microscopy was used to observe Vero-COD adhesion. Inductively coupled plasma emission spectrometry was used to quantitatively measure the amount of adhered COD microcrystals. Nanoparticle size analyzer and laser scanning confocal microscopy were performed to measure the change in the zeta potential on the Vero cell surface and the change in osteopontin expression during the adhesion process, respectively. The level of cell injury was evaluated by measuring the changes in malonaldehyde content, and cell viability during the adhesion process. Results: The adhesion capacity of Vero cells in the injury group to COD microcrystals was obviously stronger than that of Vero cells in the control group. After adhesion to COD, cell viability dropped, both malonaldehyde content and cell surface zeta potential increased, and the fluorescence intensity of osteopontin decreased because the osteopontin molecules were successfully covered by COD. Submicron COD further damaged the cells during the adhesion process, especially for Vero cells in the control group, leading to an elevated amount of attached microcrystals. Conclusion: Submicron COD can further damage injured Vero cells during the adhesion process. The amount of attached microcrystals is proportional to the degree of cell damage. The increased amount of microcrystals that adhered to the injured epithelial cells plays an important role in the formation of early-stage kidney stones.

In Vitro Studies Reveal Antiurolithic Effect of Antioxidant Sulfated Polysaccharides from the Green Seaweed Caulerpa cupressoides var flabellata

“…Other typical signals of COM crystal were observed around 947, 885 and 663 cm −1 (Figure 4, COM spectra), whereas characteristic COD signals were observed at 916 and 609 cm −1 . Both spectra are similar to those previously described for COM and COD crystals [34,35].…”

Effects of Calcium Oxalate on Expression of Clusterin and Lower Urinary Tract Symptoms in Prostatitis and Benign Prostatic Hyperplasia Patients with Calculi

“…It is reported that calcium oxalate monohydrate (COM) is involved in hyperoxaluria, while calcium oxalate dihydrate (COD) is related to hypercalciuria [9]. The CaOx formation process comprises nucleation, development, clustering, and cell adhesion [10,11]. CaOx stones frequently possess a core-shell structure.…”

Alpha-tubulin enhanced renal tubular cell proliferation and tissue repair but reduced cell death and cell-crystal adhesion

“…Many previous reports have shown that CaOx not only induced renal tubular cell injury but also enhanced crystal attachment on renal cell surface 5 28 29 . When crystals adhered on the epical cell surface, it could damage cell membrane 6 30 . To prove the hypothesis that α-tubulin overexpression could protect crystal attachment, cell-crystal adhesion assay was performed.…”

“…Adhesion of crystals onto the cells is a critical event, which triggers many cascades of cellular response, e.g. cytotoxicity, injury, proliferation and apoptosis, that ultimately lead to kidney stone formation 6 7 . CaOx crystals also evoke inflammatory processes that can lead to fibrosis, loss of nephron and eventually ESRD 8 9 .…”