The anti-hyperuricemic and gut microbiota regulatory effects of a novel purine assimilatory strain, Lactiplantibacillus plantarum X7022.

PURPOSE: Probiotics have been reported to effectively alleviate hyperuricemia and regulate the gut microbiota. The aim of this work was to study the in vivo anti-hyperuricemic properties and the mechanism of a novel strain, Lactiplantibacillus plantarum X7022. METHODS: Purine content and mRNA expression of purine assimilation related enzymes were determined by HPLC and qPCR, respectively. Hyperuricemic mice were induced by potassium oxonate and hypoxanthine. Uric acid (UA), blood urea nitrogen, creatinine and renal inflammation were examined by kits. The expression of renal UA transporters was subjected to western blotting. Kidney tissues were sectioned for histological analysis. The fecal short-chain fatty acids (SCFAs) were determined by HPLC, and gut microbiota was investigated using the 16S rDNA metagenomic sequencing. RESULTS: L. plantarum X7022 possesses a complete purine assimilation pathway and can exhaust xanthine, guanine, and adenine by 82.1%, 33.1%, and 12.6%, respectively. The strain exhibited gastrointestinal viability as 44% at the dose of 109 CFU/mL in mice. After four-week administration of the strain, a significant decrease of 35.5% in the serum UA level in hyperuricemic mice was achieved. The diminished contents of fecal propionate and butyrate were dramatically boosted. The treatment also alleviated renal inflammation and restored renal damage. The above physiological changes may due to the inhibited xanthine oxidase (XO) activity, as well as the expressional regulation of UA transporters (GLUT9, URAT1 and OAT1) to the normal level. Notably, gut microbiota dysbiosis in hyperuricemic mice was improved with the inflammation and hyperuricemia related flora depressed, and SCFAs production related flora promoted. CONCLUSION: The strain is a promising probiotic strain for ameliorating hyperuricemia.

Lactiplantibacillus plantarum X7022 Plays Roles on Aging Mice with Memory Impairment Induced by D-Galactose Through Restoring Neuronal Damage, Relieving Inflammation and Oxidative Stress.

In this study, Lactiplantibacillus plantarum X7022 was applied to ameliorate memory impairment of aging mice induced by D-galactose. The strain showed specific choloylglycine hydrolysis ability based on in vitro investigation. Morris water maze test showed L. plantarum X7022 administration improved learning ability and spatial memory of aging mice. The gavage of L. plantarum X7022 displayed a promising ability of relieving cerebral oxidative stress and hippocampal inflammatory condition according to the increased GSH level and SOD activity and decreased MDA level, as well as decreased TNF-α, IL-1ß, and IL-6 levels. The intervention with the strain could protect neuron by regulating cell apoptosis and AChE overexpression and inhibiting amyloid-ß deposition, as well as affect neuron functions by regulating CREB-BDNF signaling pathways and iNOS expression. Besides, the strain could improve fecal SCFA contents and increase the abundance of anti-inflammatory and antioxidant-related genera such as Lactobacillus, Akkermansia, and Adlercreutzia. These results suggest that L. plantarum X7022 could be a prospective therapeutic alternative for the improvement of memory impairment among the elderly.