Mutant VPS35-D620N induces motor dysfunction and impairs DAT-mediated dopamine recycling pathway.

The D620N mutation in vacuolar protein sorting protein 35 (VPS35) gene has been identified to be linked to late onset familial Parkinson disease (PD). However, the pathophysiological roles of VPS35-D620N in PD remain unclear. Here, we generated the transgenic Caenorhabditis elegans overexpressing either human wild type or PD-linked mutant VPS35-D620N in neurons. C. elegans expressing VPS35-D620N, compared with non-transgenic controls, showed movement disorders and dopaminergic neuron loss. VPS35-D620N worms displayed more swimming induced paralysis but showed no defects in BSR assays, thus indicating the disruption of dopamine (DA) recycling back inside neurons. Moreover, VPS35 formed a protein interaction complex with DA transporter (DAT), RAB5, RAB11 and FAM21. In contrast, the VPS35-D620N mutant destabilized these interactions, thus disrupting DAT transport from early endosomes to recycling endosomes, and decreasing DAT at the cell surface. These effects together increased DA in synaptic clefts, and led to dopaminergic neuron degeneration and motor dysfunction. Treatment with reserpine significantly decreased the swimming induced paralysis in VPS35-D620N worms, as compared with vehicle treated VPS35-D620N worms. Our studies not only provide novel insights into the mechanisms of VPS35-D620N-induced dopaminergic neuron degeneration and motor dysfunction via disruption of DAT function and the DA signaling pathway but also indicate a potential strategy to treat VPS35-D620N-related PD and other disorders.

Population pharmacokinetics of tacrolimus in Chinese adult liver transplant patients.

Tacrolimus is widely used in organ transplantation to prevent rejection. However, the narrow therapeutic window and the large inter-and intra-individual variability in the pharmacokinetics (PK) of tacrolimus make it difficult for individualization of dosing. This study aimed at developing a population pharmacokinetic model for estimating the oral clearance of tacrolimus in Chinese liver transplant patients, and identifying factors that contribute to the PK variability of tacrolimus. Data of 151 liver transplant patients who received tacrolimus were analyzed in this study. The population PK model was analyzed and the covariates including population demographic and biochemical characteristics, drug combination, and genetic polymorphism were explored using non-linear mixed-effects modeling approach. A single-compartment population PK model was developed, and the final model was CL/F = (14.6-2.38 × cytochrome P450 (CYP) 3A5-3.72 × WZC+1.04 × (POD/9)+2.48 × COR) × Exp(ηi ), where CYP3A5 was 1 for CYP3A5*3/*3, Wuzhi Capsule (WZC) was 1 when patients took tacrolimus combined with WZC, otherwise it was 0, corticosteroids (COR) was 1 when patients take tacrolimus combined with COR, otherwise, it was 0, POD was the post-operative day. Visual inspection and bootstrap indicated that the final model was stable and robust. In this study, we developed the first tacrolimus population PK model in Chinese adult liver transplant patients. We first determined the influence of WZC on tacrolimus in these people, which could provide useful PK information for the drug combination of tacrolimus and WZC. We also revealed the influence of genetic polymorphism of CYP3A5, POD, and a combination of COR on tacrolimus PK. Therefore, these significant factors should be taken into consideration in optimizing dosage regimens.

Association of ADAM10 gene variants with sporadic Parkinson's disease in Chinese Han population.

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide. Genetic factors play important roles in PD risk. rs653765 and rs514049 of ADAM10 were reported to be associated with Alzheimer's disease (AD) in Caucasian population; however, the association of the two variants with PD in Chinese Han population remains unknown. The present investigation aimed to explore the possible association of ADAM10 variants with PD in Chinese Han population. METHODS: We enrolled 565 PD patients and 518 healthy controls to conduct a case-control study. DNA samples were extracted from peripheral blood leukocytes, and the genotypes were determined by utilization of MassARRAY platform. Plasma levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: We found CC genotype of rs514049 was associated with an increased risk of PD (OR (95% CI) = 3.776 (1.127-11.217), p = 0.018). The C allele frequency of rs514049 was significantly higher in PD group (OR (95% CI) = 1.328 (1.031-1.709), p = 0.028), especially in male subgroup (OR (95% CI) = 1.484 (1.053-2.092), p = 0.024). However, there was no significant difference in the genotype or allele frequencies for rs653765 within the groups. Plasma levels were significantly decreased in PD patients compared with controls (p < 0.001). CONCLUSIONS: Our data suggested that C allele of rs514049 in ADAM10 may increase the risk of PD in Chinese Han population, especially in males. The decreased plasma levels are probably involved in PD development.

Association of CLU gene polymorphism with Parkinson's disease in the Chinese Han population.

BACKGROUND: Clusterin (CLU) plays important role in the pathology of neurodegenerative disorders. Recently, a genetic variant of CLU rs9331896 has been reported as a risk estimate for Alzheimer's disease (AD). However, the association between this variant and the risk of Parkinson's disease (PD) in the Chinese Han population remains elusive. METHODS: We sequenced CLU rs9331896 in 353 PD patients and 326 healthy-matched individuals of the Chinese Han population. The genotypes of rs9331896 were analyzed using MassArray (Agena Bioscience, San Diego, CA, USA) in accordance with the manufacturer's instructions. The distribution of genotypes and allelic frequencies was analyzed by a chi-squared test. Additionally, the expression of CLU protein in plasma was evaluated by an enzyme-linked immunosorbent assay and analysed with a t-test. RESULTS: The TT genotype in rs9331896 in a recessive model was found to be associated with the increased risk of PD (odds ratio = 1.408, 95% confidence interval = 1.034-1.916, p = 0.029). Subgroup analysis indicated that TT genotype carriers showed a significantly higher risk in male PD patients compared to male healthy controls (odds ratio = 1.611, 95% confidence interval = 1.046-2.483, p = 0.030). In addition, CLU levels in the plasma of PD patients were significantly higher than controls (p = 0.024). CONCLUSIONS: The CLU-rs9331896-TT genotype was a risk factor for PD, particularly in males. PD patients also expressed a high level of CLU in plasma.

microRNA-29a regulates liver tumor-initiating cells expansion via Bcl-2 pathway.

MicroRNAs (miRNAs) participate in tumorigenesis, progression, recurrence and drug resistance of hepatocellular carcinoma (HCC). However, few miRNAs have been identified and entered clinical practice. Herein, we report that miR-29a is downregulated in tumor-initiating cells (T-ICs) and has an important function in liver T-ICs. Functional studies revealed that miR-29a knockdown promotes liver T-ICs self-renewal and tumorigenesis. Conversely, a forced miR-29a expression inhibits liver T-ICs self-renewal and tumorigenesis. Mechanistically, we find that miR-29a downregulates Bcl-2 via binding its mRNA 3'UTR in liver T-ICs. The correlation between miR-29a and Bcl-2 is validated in human HCC tissues. Furthermore, the miR-29a expression determines the responses of hepatoma cells to sorafenib treatment. Analysis of patient-derived xenografts (PDXs) further demonstrated that the miR-29a high patients are more sensitive to sorafenib treatment. In conclusion, our findings revealed the crucial role of the miR-29a in liver T-ICs expansion and sorafenib response, rendering miR-29a as an optimal target for the prevention and intervention of HCC.

The outcome and burden of Chinese patients with neurodegenerative diseases: A 10-year clinical feature study.

BACKGROUND: As the Chinese population continues to age, the incidence of neurodegenerative diseases (NDDs) has increased dramatically, which results in heavy medical and economic burden for families and society. OBJECTIVE: The objective of this study was to evaluate NDDs in a southern Chinese hospital over a 10-year period and examine trends in demographics, outcome, length of stay (LOS) and cost. METHODS: Retrospective medical records of patients from January 2010 to December 2019 were collected, including 7231 patients with NDDs (as case group) and 9663 patients without any NDDs (as control group). The information of social demographic data, admission source, reasons for admission, outcomes, LOS, and cost were extracted and analysed. RESULT: The average hospitalisation age of the patients with NDDs is over 65 years (peak age 70-89 years). Compared with the control group, the case group had a longer LOS and a higher cost and the numbers of patients with NDDs increased yearly from 2010 to 2019. The LOS shortened while the cost increased. Clinical features affected LOS and cost. Patients suffering from infection, abnormal blood pressure and the imbalance of water-electrolyte homoeostasis as main reasons for admission were decreased; however, heart disease, cerebrovascular accident and mental diseases were significantly increased, the overall change trend of fracture/trauma remained stable. The rate of discharge to home care and mortality declined; discharge to other medical or community facilities increased over 10 years. CONCLUSION: The majority of NDDs patients tended to be older. During the last 10 years from 2010 to 2019, the numbers of NDDs patients increased yearly, the trend of LOS became shortening and the cost gradually increasing. The main reasons of admission and outcomes of hospital showed different trends.

Inhibition of allogeneic islet graft rejection by VISTA-conjugated liposome.

The Ig superfamily member V-domain Ig-containing suppressor of T-cell activation (VISTA) is a negative regulator with broad-spectrum activities and has reported that blockade of VISTA or combination with other negative checkpoint receptors sufficiently break tumor tolerance. However, it remains unclear whether VISTA could induce allogeneic T-cell hyporesponsiveness and inhibit allograft rejection. Here we found VISTA treatment significantly inhibited lymphocyte proliferation and activation in allogeneic MLR assay through impairing SYK-VAV pathway. Interestingly, though neither VISTA protein nor VISTA-Fc fusion protein administration exerted satisfactory immunosuppressive effect on allograft survival due to their short half-life in circulation, this problem was solved by conjugating VISTA protein on liposome by biotin-streptavidin system, which markedly prolonged its circulating half-life to 60 h. With islet transplant model, administration of VISTA-conjugated liposome could markedly prolong allograft survival by inhibition of SYK-VAV pathway, thus maintained the normal blood glucose level of recipients during treatment period. The results indicate VISTA is a promising therapeutic target to treat allograft rejection of islet transplantation.

Association of LAG3 genetic variation with an increased risk of PD in Chinese female population.

BACKGROUND: Emerging evidence suggests that α-synuclein (α-syn) aggregation and intercellular transmission contributes to pathogenesis of Parkinson's disease (PD) and the toxic fibrillary α-syn binds lymphocyte-activation gene 3 (LAG3) receptor that mediates α-syn transmission. The deletion of LAG3 in animal models was shown to limit α-syn spreading and alleviate the pathological changes of dopaminergic neurons and animal behavioral deficits induced by α-syn aggregation. However, little is known about the genetic association of LAG3 variation with human PD development. OBJECTIVE: Here we investigated LAG3 single nucleotide polymorphisms (SNPs) and examined the levels of soluble LAG3 (sLAG3) of CSF and serum from Chinese PD patients. METHODS: We enrolled 646 PD patients and 536 healthy controls to conduct a case-control study. All the participants were genotyped using Sequenom iPLEX Assay and the partial cerebrospinal fluid (CSF) and serum samples were assessed by Meso Scale Discovery electrochemiluminescence (MSD-ECL) immunoassay to measure sLAG3 concentration. RESULTS: As a result, distributions of rs1922452-AA (1.975, 95% confidence interval (CI) 1.311-2.888, p = 0.001) and rs951818-CC (OR = 2.03, 95% CI 1.369-3.010, p = 0.001) genotype frequencies were found higher in the female PD patients than controls, respectively, and a strong linkage disequilibrium (LD) was calculated on the variants. The level of sLAG3 in CSF of PD patients was found to significantly differ from that of controls (51.56 ± 15.05 pg/ml vs 88.49 ± 62.96 pg/ml, p < 0.0001). Meanwhile, the concentration of α-synuclein in CSF of patients was significantly lower than that of controls (939.9 ± 2900 pg/ml vs 2476 ± 4403 pg/ml, p < 0.0001) and the level of sLAG3 was detected to be positive correlation with that of α-synuclein in the control group (r = 0.597, p = 0.0042), but not in PD group (r = 0.111, p = 0.408). CONCLUSION: In summary, our data suggested that LAG3 SNPs increase the PD risk of Chinese female population and the sLAG3 may be a potential biomarker predicted for PD development.

Iron promotes α-synuclein aggregation and transmission by inhibiting TFEB-mediated autophagosome-lysosome fusion.

Recent studies have strongly shown that cell-to-cell transmission of neuropathogenic proteins is a common mechanism for the development of neurodegenerative diseases. However, the underlying cause is complex and little is known. Although distinct processes are involved in the pathogenesis of various diseases, they all share the common feature of iron accumulation, an attribute that is particularly prominent in synucleinopathies. However, whether iron is a cofactor in facilitating the spread of α-synuclein remains unclear. Here, we constructed a cell-to-cell transmission model of α-synuclein using SN4741 cell line based on adenovirus vectors. Cells were treated with FeCl2, and α-synuclein aggregation and transmission were then evaluated. In addition, the possible mechanisms were investigated through gene knockdown or over-expression. Our results demonstrated that iron promoted α-synuclein aggregation and transmission by inhibiting autophagosome-lysosome fusion. Furthermore, iron decreased the expression of nuclear transcription factor EB (TFEB), a master transcriptional regulator of autophagosome-lysosome fusion, and inhibited its nuclear translocation through activating AKT/mTORC1 signaling. After silencing TFEB, ratios of α-synuclein aggregation and transmission were not significantly altered by the presence of iron; on the other hand, when TFEB was over-expressed, the transmission of α-synuclein induced by iron was obviously reversed; suggesting the mechanism by which iron promotes α-synuclein transmission may be mediated by TFEB. Taken together, our data reveal a previously unknown relationship between iron and α-synuclein, and identify TFEB as not only a potential target for preventing α-synuclein transmission, but also a critical factor for iron-induced α-synuclein aggregation and transmission. Indeed, this newly discovered role of iron and TFEB in synucleinopathies may provide novel targets for developing therapeutic strategies to prevent α-synuclein transmission in Parkinson's disease.

lncRNA SNHG8 Promotes the Tumorigenesis and Metastasis by Sponging miR-149-5p and Predicts Tumor Recurrence in Hepatocellular Carcinoma.

BACKGROUND/AIMS: Long noncoding RNAs (lncRNAs) are aberrantly expressed in multiple malignant tumors involved in tumor growth and metastasis. Accumulating data show that small nucleolar RNA host gene (SNHG) 1/12/20 plays a key role in the progression of hepatocellular carcinoma (HCC). However, the molecular mechanisms by which SNHG8 contributes to HCC remain elusive and merit exploration. METHODS: The association between SNHG8 expression and the clinicopathological characteristics and prognoses in HCC patients was analysed by using qRT-PCR analysis and the data from The Cancer Genome Atlas. Cell growth and metastatic potential were determined by MTT, colony formation, Transwell assays, and the mouse xenograft tumor model and lung metastasis model. Epithelial-mesenchymal transition markers were detected by western blot analysis. The binding capacity of SNHG8 with miRNAs was evidenced by bioinformatic analysis and a luciferase reporter assay. In addition, the rescue experiments were performed based on co-transfection with sh-SNHG8 and a miR-149 inhibitor in HCC cells. RESULTS: The expression levels of lncRNA SNHG8 were dramatically increased in HCC tissues and cell lines as compared with the adjacent normal tissues, and SNHG8 expression was an independent prognostic factor of tumor recurrence in HCC patients. Furthermore, knockdown of SNHG8 inhibited cell proliferation, invasion, and lung metastasis in vitro and in vivo, whereas overexpression of SNHG8 reversed these effects. SNHG8 acted as a sponge of miR-149 and counteracted the tumor suppressive effects of mi R-149 in HCC cells. Expression of phosphatase, Mg2+/Mn2+ dependent 1F, a target of R-149, displayed a negative correlation with miR-149 expression but a positive correlation with SNHG8 expression in HCC specimens. CONCLUSION: As lncRNA SNHG8 may promote HCC tumorigenesis and metastasis by sponging miR-149, it is a potential candidate marker and therapeutic target for HCC.

MicroRNA-500a Promotes the Progression of Hepatocellular Carcinoma by Post-Transcriptionally Targeting BID.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is one of the most common human malignant diseases in the world, and the mechanisms underlying HCC carcinogenesis and progression need further investigation. MicroRNAs play important roles in the development of cancer, and miR-500a is suggested to be deregulated in some types of cancer. However, the underlying molecular mechanisms of miR-500a in HCC remain unknown. METHODS: The expression of miR-500a in HCC was analyzed in The Cancer Genome Atlas (TCGA) database and examined in 33 pairs of HCC tissues and matched nontumor tissues. The correlation between miR-500a expression and prognosis of HCC patients was analyzed from the survival data in TCGA. The mechanism of miR-500a upregulation in HCC was detected using chromatin immunoprecipitation-quantitative real-time PCR. The roles of miR-500a in HCC development were examined using a cell counting kit-8 assay in vitro and growth of transplanted tumors in nude mice in vivo. Apoptosis of HCC was detected using Annexin V/propidium iodide staining. The expression of BH3-interacting death agonist (BID) protein was examined using western blot analysis. RESULTS: miR-500a expression was upregulated in HCC tissues, and high miR-500a expression was significantly correlated with the poor prognosis of HCC patients. Histone modifications in the promoter region of miR-500a may be responsible for its increased expression. Inhibition of miR-500a in HCC cell lines significantly promoted apoptosis, as well as inhibiting the proliferation of HCC cells and growth of transplanted tumors in nude mice. miR-500a directly targeted the 3' untranslated region of BID mRNA, and inhibition of miR-500a-promoted apoptosis was almost completely abolished by the administration of ABT-199 via the BID-mitochondria pathway. CONCLUSION: Our results suggest that histone modifications in the promoter region of miR-500a may be responsible for the increased expression of miR-500a in HCC, which promotes cancer progression by targeting BID, indicating that miR-500a may be a potential prognostic predictor and therapeutic target for HCC patients.

Association of DNMT3b gene variants with sporadic Parkinson's disease in a Chinese Han population.

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide. Epigenetic modifications, specifically DNA methylation, have been implicated in the development of this disease. Genetic variants of DNA methyltransferase 3b (DNMT3b), one of the most important DNA methyltransferases, were shown to be associated with PD in a Brazilian population. However, it is unclear whether genetic variants of DNMT3b increase the risk of PD in the Chinese Han people. The present study aimed to investigate the association of the DNMT3b variants rs2424913, rs998382 and rs2424932 with PD in a Chinese Han population. METHODS: We studied 487 Chinese Han patients with sporadic PD and 485 healthy age-, sex- and ethnicity-matched controls. DNA was extracted from peripheral blood leukocytes and the individual genotypes were determined using the SNaPshot method. RESULTS: We found that the rs2424932 and rs998382 variants were significantly associated with an increased risk of PD compared to the controls [rs2424932: odds ratio (OR) = 1.632, 95% confidence interval (CI) = 1.108-2.406, p = 0.013; rs998382: OR = 1.612, 95% CI = 1.103-2.382, p = 0.014]. Subgroup analysis suggested that female patients carrying the rs2424932 or rs998382 variants were more likely to develop PD than female controls (rs2424932: OR = 3.863, 95% CI = 2.004-7.445, p < 0.001; rs998382: OR = 3.679, 95% CI = 1.943-6.964, p < 0.001). Haplotype analysis indicated that the three variants comprised one block and that the Trs2424913 -Crs998382 -A rs2424932 haplotype was correlated with an increased risk of PD (p = 0.0046), especially for Chinese Han females (p < 0.0001). CONCLUSIONS: The results of the present study strongly suggest that DNMT3b variants are associated with PD in the Chinese Han people, especially females.

Excessive intraoperative blood loss independently predicts recurrence of hepatocellular carcinoma after liver transplantation.

BACKGROUND: Several studies have investigated the effect of intraoperative blood loss (IBL) on recurrence of tumors. However, the independent effect of IBL on oncological outcome after liver transplantation (LT) for hepatocellular carcinoma (HCC) is unclear. METHODS: A total of 479 patients who underwent LT for HCC from January 2001 to December 2012 at our institution were enrolled in this retrospective study. Kaplan-Meier and Cox regression methods were used to assess the recurrence rate, as well as its risk factors. Stratified analysis was performed to further examine the effect of IBL on HCC recurrence according to different characteristics of tumors. We also investigated the independent risk factors for excessive IBL using logistic regression analysis. RESULTS: The median follow-up was 28 months (range, 1-131 months). Kaplan-Meier analysis with the log-rank test according to IBL at per liter intervals showed that IBL > 4 L was significantly associated with a higher recurrence rate (P < 0.001). Multivariate analysis identified that IBL > 4 L (P < 0.001; hazard ratio [HR] = 2.32, 95 % confidence interval [CI] = 1.60-3.36) was an independent risk factor for post-LT HCC recurrence, as well as age < 60 years, exceeding Milan criteria, α-fetoprotein levels > 400 ng/mL, and micro- and macrovascular invasion. IBL > 4 L (P < 0.001; HR = 2.45, 95 % CI = 1.64-3.66) was also independently associated with early (within 1 year) recurrence after LT. Furthermore, a significant correlation between IBL > 4 L and vascular invasion (P = 0.019) was found. IBL > 4 L was independently associated with HCC recurrence for patients with vascular invasion, but not for patients without vascular invasion. Finally, we found that the presence of ascites, model for end-stage liver disease score, and operation time were independent risk factors for IBL > 4 L. CONCLUSIONS: Excessive IBL is an independent predictor of HCC recurrence after LT, especially in patients with vascular invasion.

Expression of human Ras-related protein Rab39B variant T168K in Caenorhabditis elegans leads to motor dysfunction and dopaminergic neuron degeneration.

Human RAB39B gene is related to familial early-onset Parkinson disease. In early adulthood, men with the RAB39B c.503C > A (Thr168Lys, p. T168K) mutation develop typical tremor, bradykinesia, and alpha-synuclein accumulation. We investigated the pathological mechanism of RAB39B T168K in a Caenorhabditis elegans model. In early adult C. elegans, RAB39B T168K led to dopaminergic neuron degeneration that presented as disrupted dendrites and blunt neuronal cells. Abnormal dopamine secretion was inferred from a decline in motor function and a positive basal slowing phenotype. Dopamine-associated tests confirmed that synthesis and recycling of dopamine were normal. The RAB39B T168K mutation might impair dopamine vesicular transmission from the presynaptic membrane to the synaptic gap in dopaminergic neurons. The release-dependent feedback mechanism in neurotransmitters regulates the balance of receptor activities. Protein-protein interactions network analysis revealed that RAB39B may also function in lysosomal degradation and autophagy. Impaired disposal of misfolded α-synuclein eventually leads to protein aggregation. Thus, like other members of the Rab family, RAB39B may be involved in vesicular transport associated with dopamine secretion and α-synuclein clearance.

A skin-specific α-Synuclein seeding amplification assay for diagnosing Parkinson's disease.

The seeding amplification assay (SAA) has recently emerged as a valuable tool for detecting α-synuclein (αSyn) aggregates in various clinically accessible biospecimens. Despite its efficiency and specificity, optimal tissue-specific conditions for distinguishing Parkinson's disease (PD) from non-PD outside the brain remain underexplored. This study systematically evaluated 150 reaction conditions to identify the one with the highest discriminatory potential between PD and non-synucleinopathy controls using skin samples, resulting in a modified SAA. The streamlined SAA achieved an overall sensitivity of 92.46% and specificity of 93.33% on biopsy skin samples from 332 PD patients and 285 controls within 24 h. Inter-laboratory reproducibility demonstrated a Cohen's kappa value of 0.87 (95% CI 0.69-1.00), indicating nearly perfect agreement. Additionally, αSyn seeds in the skin were stable at -80 °C but were vulnerable to short-term exposure to non-ultra-low temperatures and grinding. This study thoroughly investigated procedures for sample preprocessing, seed amplification, and storage, introducing a well-structured experimental framework for PD diagnosis using skin samples.

Phosphorylation of AQP4 by LRRK2 R1441G impairs glymphatic clearance of IFNγ and aggravates dopaminergic neurodegeneration.

Aquaporin-4 (AQP4) is essential for normal functioning of the brain's glymphatic system. Impaired glymphatic function is associated with neuroinflammation. Recent clinical evidence suggests the involvement of glymphatic dysfunction in LRRK2-associated Parkinson's disease (PD); however, the precise mechanism remains unclear. The pro-inflammatory cytokine interferon (IFN) γ interacts with LRRK2 to induce neuroinflammation. Therefore, we examined the AQP4-dependent glymphatic system's role in IFNγ-mediated neuroinflammation in LRRK2-associated PD. We found that LRRK2 interacts with and phosphorylates AQP4 in vitro and in vivo. AQP4 phosphorylation by LRRK2 R1441G induced AQP4 depolarization and disrupted glymphatic IFNγ clearance. Exogeneous IFNγ significantly increased astrocyte expression of IFNγ receptor, amplified AQP4 depolarization, and exacerbated neuroinflammation in R1441G transgenic mice. Conversely, inhibiting LRRK2 restored AQP4 polarity, improved glymphatic function, and reduced IFNγ-mediated neuroinflammation and dopaminergic neurodegeneration. Our findings establish a link between LRRK2-mediated AQP4 phosphorylation and IFNγ-mediated neuroinflammation in LRRK2-associated PD, guiding the development of LRRK2 targeting therapy.