Parkinson’s disease (PD) is a neurodegenerative disease (NDD) with high and ongoing morbidity, bringing heavy burdens to PD patients seriously. Finding neurotrophic drugs still remains vital due to the limited drug spectrum available currently. Substantial evidence suggests that glucagon-like peptide 1 (GLP-1) exerts neuroprotection on PD, yet the short-lived biological activity markedly hindered its application. Herein, we investigated the neurotrophic role of the next-generation probiotic strain L. lactis MG1363-pMG36e-GLP-1 in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice and elucidated the mechanisms. Our data suggested that L. lactis MG1363-pMG36e-GLP-1 markedly enhanced motor deficits induced by MPTP via rescuing dopaminergic (DAergic) neurodegeneration in substantia nigra (SN). We found that L. lactis MG1363-pMG36e-GLP-1 exerts neurotrophic effects via activating the Keap1/Nrf2/GPX4 signalling pathway to down-regulate ACSL4 and up-regulate FSP1 to suppress ferroptosis. Additionally, the decreased oxidative stress levels via suppressing generations of ROS and MDA supported our findings. Lastly, we identified that the L. lactis MG1363-pMG36e-GLP-1 administration reversed dysbiosis in PD mice by increasing Akkermansia, Oscillospira, and Sutterella at the genus level. These results indicated that the neurotrophic effects of the next-generation probiotics L. lactis MG1363-pMG36e-GLP-1 against MPTP-induced Parkinsonism are mediated by modulating oxidative stress, inhibiting ferroptosis, and redressing dysbiosis.

Evidence has revealed that oestrogen deprivation-induced osteolysis is microbiota-dependent and can be treated by probiotics. However, the underlying mechanism require further investigation. This study aims to provide additional evidence supporting the use of probiotics as an adjuvant treatment and to explore the pathophysiology of oestrogen-deprived osteolysis. Forty-five SD rats were randomly divided into five groups (n = 9). Rats from four groups were ovariectomised and treated with NS, calcium, probiotics, or calcium + probiotics, while one group underwent a sham operation and was treated with NS. The osteometabolic effects were evaluated, and the mechanistic role of the probiotic supplement was explored. Intragastric administration of Bifidobacterium animalis subsp. lactis LPL-RH (LPL-RH) markedly suppressed osteoclastic activation and bone calcium loss by downregulating TRAP enzymatic activity, the OPG/RANKL ratio, and the downstream signalling pathway RANKL/TRAF6/NF-κB/NFATc1/TRAP in ovariectomised SD rats. LPL-RH also reduced CD4+IL-17 A+ TH17 cells in the bone marrow, the pro-osteoclastogenic cytokine IL-17 A, pro-inflammatory molecules (LPS), and its binding protein (LBP) in the blood. LPL-RH restored intestinal ZO-1, occludin, claudin 2, claudin 12, and claudin 15, which improved ileal histopathology, reduced ileal oxidative stress, and attenuated the LPS-responsive TLR4/MyD88/NF-κB pathway. Furthermore, 16 S rRNA sequencing revealed that LPL-RH altered the faecal microbiome by reducing the relative abundance of S24-7 at the family level and promoting Prevotella and Bacteroides at the genus level. Collectively, LPL-RH suppressed osteoclastogenesis and osteolysis by modulating type 17 immunity and gut microbiome.

JOURNAL/nrgr/04.03/01300535-202603000-00044/figure1/v/2026-04-22T011420Z/r/image-tiff Parkinson’s disease is characterized by synucleinopathy-associated neurodegeneration. Previous studies have shown that glucagon-like peptide-1 (GLP-1) has beneficial effects in a mouse model of Parkinson’s disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. However, the effect of GLP-1 on intrinsic synuclein malfunction remains unclear. In this study, we investigated the effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism in Snca ^A53T transgenic mice and explored the underlying mechanisms. Our data showed that Lactococcus lactis MG1363-pMG36e-GLP-1 inhibited dopaminergic neuronal death, reduced pathological aggregation of α-synuclein, and decreased movement disorders in SncaA53T transgenic mice. Furthermore, Lactococcus lactis MG1363-pMG36e-GLP-1 downregulated lipopolysaccharide-related inflammation, reduced cerebral activation of microglia and astrocytes, and promoted cell survival via the GLP-1 receptor/PI3K/Akt pathway in the substantia nigra. Additionally, Lactococcus lactis MG1363-pMG36e-GLP-1 decreased serum levels of pro-inflammatory molecules including lipopolysaccharide, lipopolysaccharide binding protein, interleukin-1β, and interleukin-6. Gut histopathology and western blotting further revealed that Lactococcus lactis MG1363-pMG36e-GLP-1 increased the expression of gut integrity–related proteins and reduced lipopolysaccharide-related inflammation by reversing gut dysbiosis in Snca ^A53T transgenic mice. Our findings showed that the beneficial effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism traits in Snca ^A53T transgenic mice is mediated by microglial polarization and the reversal of dysbiosis. Collectively, our findings suggest that Lactococcus lactis MG1363-pMG36e-GLP-1 is a promising therapeutic agent for the treatment of Parkinson’s disease.