Abstract:

Objective To investigate the effect of Lactobacillus plantarum LB12 on kidney calcium oxalate stones in rats. Methods A total of 24 male SD rats aged 6 ~ 8 weeks were randomly divided into four groups： control group， model group， LB12 group， and LB12 intervention group， with 6 rats in each group. The control group and LB12 group had free access to water， and were gavaged with 2 mL of normal saline in the morning. In the evening， the control group received 2 mL of normal saline， while the LB12 group received 2 mL of Lactobacillus plantarum LB12 suspension. The model group and LB12 intervention group were given 1% ethylene glycol in drinking water and 2 mL of 2% ammonium chloride solution via gavage in the morning. In the evening， both groups received 2 mL of normal saline and 2 mL of Lactobacillus plantarum LB12 suspension， respectively. After the experiment， the body weight change trend of the rats was recorded， and the levels of urinary calcium， urinary oxalate， serum creatinine， blood urea nitrogen， renal SOD， and MDA were measured. Additionally， H&E staining， VK staining， immunohistochemistry， ROS fluorescence analysis， and Western blot （WB） were performed on kidney tissues. Results Lactobacillus plantarum LB12 demonstrated a 12.34% oxalate degradation rate in vitro. Further animal experiments indicated that Lactobacillus plantarum LB12 alleviated the weight loss trend in the model rats and reduced the levels of urinary calcium， urinary oxalate， serum creatinine， urea nitrogen， and MDA， while increasing SOD levels （P < 0.05）. Histopathological analysis revealed that the LB12 intervention group had significantly fewer renal crystals compared to the model group， with lower expressions of IL-6 and ROS （P < 0.01）. Western blot analysis demonstrated that Lactobacillus plantarum LB12 inhibited the expression of TLR4， NF-κB， and OPN proteins （P < 0.01）. Conclusions Lactobacillus plantarum LB12 can effectively alleviate the oxidative stress damage caused by calcium oxalate stones to the kidneys and reduce kidney crystal formation in rats. Furthermore， it inhibits the expression of TLR4/NF-κB and OPN， making it a potential therapeutic approach for the prevention and treatment of kidney calcium oxalate stones.

Key words: calcium oxalate, lactobacillus plantarum, oxidative stress, TLR4, OPN