Involvement of VKORC1 in the Inhibition of Calcium Oxalate Crystal Formation in HK-2 Cells

Summary： The vitamin K epoxide reductase complex subunit 1 （VKORC1）, the rate-limiting enzyme for vitamin K recycling, is significantly down-regulated in the kidneys of urolithiasis patients. This study searched for direct evidence to define the inhibitory activity of VKORC1 against calcium oxalate （CaOx） crystal formation. In the experiment of VKORC1 overexpression, HK-2 cells were transfected with the pFLAG-CMV-7.1-VKORC1 plasmid as a pFLAG-CMV-7.1-VKORC1 transfection group or the pFLAG-CMV-7.1 plasmid as a pFLAG-CMV-7.1 control group. In the experiment of VKORC1 knockdown, HK-2 cells were transfected with the PGPU6/GFP/Neo-VKORClshRNA-2 as a PGPU6/GFP/Neo-VKORClshRNA-2 transfection group or the PGPU6/GFP/Neo-shRNA-NC plasmid as a PGPU6/GFP/Neo-shRNA-NC control group. The expression of VKORC1 in HK-2 cells was detected by real-time quantitative PCR and Western blotting. The CaOx crystal formation was observed under the laser-scanning confocal microscope. It was found that the expression levels of VKORC1 mRNA and protein were significantly higher in the pFLAG-CMV-7.1-VKORC 1 transfection group than in the pFLAG-CMV-7.1 control group （P〈0.01）. The number of CaOx crystals in HK-2 cells incubated in fluorescently labeled CaOx monohydrate （COM） crystal medium for 48 h was 14±4 per field （100×） in the pFLAG-CMV-7.1-VKORC1 transfection group and 26±5 per field （100×） in the pFLAG-CMV-7.1 control group respectively under the laser-scanning confocal microscope. The amount of CaOx crystal aggregation and formation in the pFLAG-CMV-7.1-VKORC 1 transfection group was significantly reduced as compared with the pFLAG-CMV-7.1 control group （P〈0.05）. The expression levels of VKORC 1 mRNA and protein were significantly lower in the PGPU6/GFP/Neo-VKORC 1 shRNA-2 transfection group than in the PGPU6/GFP/Neo-shRNA-NC control group （P〈0.05）. The number of CaOx crystals in HK-2 cells incubated in fluorescently labeled COM crystal medium was 65±11 per field （100x） in the PGPU6/GFP/Neo-VKORC 1 shRNA-2 transfection group and 24±6 per field （100×） in the PGPU6/GFP/Neo-shRNA-NC control group respectively under the laser-scanning confocal microscope. The amount of CaOx crystal aggregation and formation in the PGPU6/GFP/Neo-VKORClshRNA-2 transfection group was significantly increased as compared with the PGPU6/GFP/Neo-shRNA-NC control group （P〈0.05）. These findings suggested that the VKORC 1 protein could inhibit CaOx salt crystallization, adhesion and aggregation. This research would help us to understand the mechanisms involving the interaction between crystallization and epithelial cells and the formation of CaOx. Key words： calcium oxalate crystals; kidney stone; vitamin K epoxide reduetase complex subunit 1; laser-scanning confocal microscopy

A Review on Kidney Stone and Its Herbal Treatment

Medicinal plants have been valued for millennia as a rich source of therapeutic compounds for the prevention of various ailments all throughout the world.Kidney stones and urinary calculi affect a huge percentage of the population nowadays.Stone sickness has become more prevalent as a result of changes in living conditions,such as industrialization and hunger.The most common stone recorded in India is calcium oxalate kidney stones.Changes in prevalence and incidence,the occurrence of stone kinds and stone position,and stone removal treatment are all discussed.Medicinal herbs have been utilised for centuries because they are safer,more effective,culturally acceptable,and have less adverse effects than manufactured medications.Patients are advised to consume a low-fat diet,as well as fibres from naturally occurring plants and herbal treatments.The current article discusses the steps that should be taken to maximise the potential of medicinal plants for stone dissolving action.Combining herbal remedies with allopathic treatment is an excellent way to eliminate all issues associated with kidney stones.The purpose of this article is to emphasise the use of herbs as a treatment for urinary stones.