Increasing evidence shows that the early lesions of Parkinson's disease (PD) originate from gut, and correction of microbiota dysbiosis is a promising therapy for PD. FLZ is a neuroprotective agent on PD, which has been validated capable of alleviating microbiota dysbiosis in PD mice. However, the detailed mechanisms still need elucidated. Through metabolomics and 16S rRNA analysis, we identified glycoursodeoxycholic acid (GUDCA) was the most affected differential microbial metabolite by FLZ treatment, which was specially and negatively regulated by Clostridium innocuum, a differential microbiota with the strongest correlation to GUDCA production, through inhibiting bile salt hydrolase (BSH) enzyme. The protection of GUDCA on colon and brain were also clarified in PD models, showing that it could activate Nrf2 pathway, further validating that FLZ protected dopaminergic neurons through promoting GUDCA production. Our study uncovered that FLZ improved PD through microbiota-gut-brain axis, and also gave insights into modulation of microbial metabolites may serve as an important strategy for treating PD.

Although enteric glial cell (EGC) abnormal activation is reported to be involved in the pathogenesis of Parkinson's disease (PD), and inhibition of EGC gliosis alleviated gut and dopaminergic neuronal dysfunction was verified in our previous study, the potential role of gut microbiota on EGC function in PD still need to be addressed. In the present study, fecal microbiota transplantation revealed that EGC function was regulated by gut microbiota. By employing 16S rRNA and metabolomic analysis, we identified that 3-indolepropionic acid (IPA) was the most affected differential microbial metabolite that regulated EGC gliosis. The protective effects of IPA on PD were validated in rotenone-stimulated EGCs and rotenone (30 mg/kg i.g. for 4 weeks)-induced PD mice, as indicated by decreased inflammation, improved intestinal and brain barrier as well as dopaminergic neuronal function. Mechanistic study showed that IPA targeted pregnane X receptor (PXR) in EGCs, and inhibition of IL-13Rα1 involved cytokine-cytokine receptor interaction pathway, leading to inactivation of downstream JAK1-STAT6 pathway. Our data not only provided evidence that EGC gliosis was critical in spreading intestinal damage to brain, but also highlighted the potential role of microbial metabolite IPA in alleviating PD pathological damages through gut-brain axis.

[This corrects the article DOI: 10.1016/j.apsb.2025.02.029.].

ObjectiveTo compare and evaluate the improvement degree of spermatogenic dysfunction mice at different recovery periods after cyclophosphamide modeling. MethodsForty-eight male ICR mice aged 4-5 weeks with the body weight of approximately 18-20 g were randomly divided into three control groups and three model groups, with 8 mice in each group. Each mouse of three model groups was intraperitoneally injected with 60 mg/kg cyclophosphamide continuously from the 1^st to 7^th day of the experiment, while each mouse of three control groups was intraperitoneally injected with the corresponding volume of normal saline. Then these mice were continued to be fed for another 7, 14 and 21 days after cyclophosphamide injection, respectively. A corresponding control group was set for each model group. The mice in each group were sacrificed after blood collection through orbital veins at corresponding time points. Testis, epididymis and seminal vesicle were taken and weighed, and their reproductive organ indexes were calculated. Histopathological changes of testis and epididymis were compared after HE staining.Sperm quality analysis was used to determine sperm-related indexes. Serum reproductive hormone content, testicular oxidative stress level and testicular signature enzyme activity were detected by ELISA and related kits.Results Compared with the control group, on the 7^th, 14^th and 21^st day after cyclophosphamide treatment, the testicular index of mice in the model group decreased significantly (P<0.01). The epididymis index decreased significantly on the 7^th and 14^th day, and the seminal vesicle index decreased obviously on the 7^th and 21^st day (P<0.05). And the histopathological damage of testis and epididymis of the model group gradually alleviated over time. On the 7^th and 14^th day after cyclophosphamide treatment, the sperm count of the model group declined remarkably (P<0.01), the serum testosterone (T) level reduced (P<0.05), the malonaldehyde (MDA) content of testis increased significantly (P<0.01), the content of reduced glutathione (GSH) and superoxide dismutase (SOD) decreased obviously (P<0.05),the lactic dehydrogenase (LDH) activity of testis reduced obviously (P<0.05), the gamma-glutamyl transpeptidase (γ-GT) activity increased significantly (P<0.05), the latter two of which are important testicular signature enzymes. Therein on the 7^th day after cyclophosphamide treatment, the sperm motility decreased significantly (P<0.001), the rate of sperm malformation increased obviously (P<0.05), the serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) increased notably (P<0.01). Nevertheless on the 21^st day after cyclophosphamide treatment, the sperm-related indexes, the content of serum reproductive hormone, the level of testicular oxidative stress and the activity of testicular signature enzyme did not change significantly (P＞0.05). ConclusionThe reproductive toxicity in mice was more apparent on the 7^th day after intraperitoneal injection with 60 mg/kg cyclophosphamide for seven days, at which time the more desirable spermatogenic dysfunction model of mice could be established. However, with the prolongation of the recovery period, the indexes of spermatogenic dysfunction in mice gradually recovered and approached the normal level on the 21^st day after cyclophosphamide treatment.

The gut microbiota plays an important role in regulating the pharmacokinetics and pharmacodynamics of many drugs. FLZ, a novel squamosamide derivative, has been shown to have neuroprotective effects on experimental Parkinson's disease (PD) models. FLZ is under phase Ⅰ clinical trial now, while the underlying mechanisms contributing to the absorption of FLZ are still not fully elucidated. Due to the main metabolite of FLZ was abundant in feces but rare in urine and bile of mice, we focused on the gut microbiota to address how FLZ was metabolized and absorbed.

Objective:To investigate the acute and long-term toxicity of GJ-4 extracted from Gardenia jasminoides J.Ellis, and to provide safety basis for its development as a new drug for the treatment of dementia. Methods:In the acute toxicity experiment, 30 ICR mice were randomly divided into control group, gardenia extract 2.5 g/kg group and gardenia extract 5.0 g/kg group, 10 mice in each group. The mice in the 2.5 g/kg and 5.0 g/kg gardenia extract groups were administrated with GJ-4 suspension. The control group was given 0.5% sodium carboxymethyl cellulose (CMC-Na) by gavage. The mice were given continuous gavage for 7 days. The mortality, body weight and general condition of mice were recorded. The levels of ALT, ALP, BUN and creatinine (CRE) in serum were measured by automatic biochemical detector. In the long-term toxicity experiment, 75 ICR mice were divided into control group and gardenia extract 100, 250, 500, 1 000 mg/kg group according to the random number table method, 15 mice in each group. The GJ-4 suspension of Gardenia extract 100, 250, 500 and 1 000 mg/kg were administrated to the stomach respectively in the gardenia extract 100, 250, 500 and 1 000 mg/kg groups, and 0.5% CMC-Na of the same volume was administrated to the stomach in the control group once a day for 30 days. The mortality, weight and mental state of mice were recorded. The organ index and the levels of ALT, ALP and BUN in serum were observed.Results:In the acute toxicity experiment, the mental state and diet of mice in each group were good, and there was no death within 7 days. Compared with the control group, there was no significant differences in body weight, heart index, liver index and kidney index between the two groups ( P>0.05). Compared with the control group, the level of BUN (10.17 ± 0.82 mmol/L vs. 11.25 ± 0.47 mmol/L) in the gardenia extract 2.5 g/kg group significantly decreased ( P<0.05), and the level of ALP (116.0 ± 10.75 U/L vs. 148.0 ± 25.73 U/L) in the gardenia extract 5.0 g/kg group significantly decreased ( P<0.05). In the long-term toxicity experiment, the mice were in good mental state and had good diet, and no death occurred. Compared with the control group, there was no significant differences in body weight, heart index, kidney index, spleen index and serum ALT, ALP and BUN levels between the two groups ( P>0.05). The liver index (4.9 ± 0.56 vs. 4.38 ± 0.49) in the 250 mg/kg gardenia extract group significantly increased ( P<0.01), and the thymus index (0.09 ± 0.02 vs. 0.14 ± 0.04) significantly decreased ( P<0.05). Conclusions:The Gardenia jasminoides extract GJ-4 has no obvious toxicity in acute and long-term toxicity experiment, indicating that GJ-4 is safe.