Stem-leaf saponins from Panax notoginseng (SLSP) comprise numerous PPD-type saponins with diverse pharmacological properties; however, their role in Parkinson's disease (PD), characterized by microglia-mediated neuroinflammation, remains unclear. This study evaluated the effects of SLSP on suppressing microglia-driven neuroinflammation in experimental PD models, including the 1-methyl-4-phenylpyridinium (MPTP)-induced mouse model and lipopolysaccharide (LPS)-stimulated BV-2 microglia. Our findings revealed that SLSP mitigated behavioral impairments and excessive microglial activation in models of PD, including MPTP-treated mice. Additionally, SLSP inhibited the upregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) and attenuated the phosphorylation of PI3K, protein kinase B (AKT), nuclear factor-κB (NFκB), and inhibitor of NFκB protein α (IκBα) both in vivo and in vitro. Moreover, SLSP suppressed the production of inflammatory markers such as interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) in LPS-stimulated BV-2 cells. Notably, the P2Y2R agonist partially reversed the inhibitory effects of SLSP in LPS-treated BV-2 cells. These results suggest that SLSP inhibit microglia-mediated neuroinflammation in experimental PD models, likely through the P2Y2R/PI3K/AKT/NFκB signaling pathway. These novel findings indicate that SLSP may offer therapeutic potential for PD by attenuating microglia-mediated neuroinflammation.
Animals ; Panax notoginseng/chemistry* ; Saponins/pharmacology* ; Microglia/immunology* ; Mice ; NF-kappa B/immunology* ; Signal Transduction/drug effects* ; Proto-Oncogene Proteins c-akt/immunology* ; Phosphatidylinositol 3-Kinases/genetics* ; Male ; Parkinson Disease/immunology* ; Mice, Inbred C57BL ; Disease Models, Animal ; Plant Leaves/chemistry* ; Neuroinflammatory Diseases/drug therapy* ; Humans

BACKGROUNDProteasome subunits (PSMB) and transporter associated with antigen processing (TAP) loci are located in the human leukocyte antigen (HLA) Class II region play important roles in immune response and protein degradation in neurodegenerative diseases. This study aimed to explore the association between single nucleotide polymorphisms (SNPs) of PSMB and TAP and Parkinson's disease (PD).

METHODSA case-control study was conducted by genotyping SNPs in PSMB8, PSMB9, TAP1, and TAP2 genes in the Chinese population. Subjects included 542 sporadic patients with PD and 674 healthy controls. Nine identified SNPs in PSMB8, PSMB9, TAP1, and TAP2 were genotyped through SNaPshot testing.

RESULTSThe stratified analysis of rs17587 was specially performed on gender. Data revealed that female patients carry a higher frequency of rs17587-G/G versus (A/A + G/A) compared with controls. But there was no significant difference with respect to the genotypic frequencies of the SNPs in PSMB8, TAP1, and TAP2 loci in PD patients.

CONCLUSIONChinese females carrying the rs17587-G/G genotype in PSMB9 may increase a higher risk for PD, but no linkage was found between other SNPs in HLA Class II region and PD.

ATP-Binding Cassette Sub-Family B Member 2 ; genetics ; ATP-Binding Cassette, Sub-Family B, Member 3 ; genetics ; Adult ; Aged ; Antigen Presentation ; Case-Control Studies ; Cysteine Endopeptidases ; genetics ; Female ; Humans ; Male ; Middle Aged ; Parkinson Disease ; genetics ; immunology ; Polymorphism, Single Nucleotide ; Proteasome Endopeptidase Complex ; genetics

OBJECTIVEParkinson's disease (PD), a neurodegenerative disorder, has been reported to be associated with brain neuroinflammation in its pathogenesis. Herein, changes in peripheral immune system were determined to better understand PD pathogenesis and provide possible target for treatment of PD through improvement of immune disorder.

METHODS1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was intraperitoneally injected into mice to prepare PD model. Expression levels of pro-inflammatory and anti-inflammatory cytokines and transcription factors of CD4+ T lymphocyte subsets in spleen and mesenteric lymph nodes and concentrations of the cytokines in serum were examined on day 7 after MPTP injection. Percentages of CD4+ T lymphocyte subsets were measured by flow cytometry.

RESULTSMPTP induced PD-like changes such as motor and behavioral deficits and nigrostriatal impairment. Expression levels of the pro-inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-2, IL-17 and IL-22, in spleen and mesenteric lymph nodes were upregulated and their concentrations in serum were elevated in PD progression. But, the concentrations of the anti-inflammatory cytokines including IL-4, IL-10 and transforming growth factor (TGF)-β were not altered in the two lymphoid tissues or serum of PD mice. In addition, expression of T-box in T cells (T-bet), the specific transcription factor of helper T (Th) 1 cells, was downregulated, but expression of transcription factor forkhead box p3 (Foxp3), the transcription factor of regulatory T (Treg) cells, was upregulated. In support of the results, the numbers of IFN-γ-producing CD4+ cells (Th1 cells) were reduced but CD4+CD25+ cells (Treg cells) were elevated in both the lymphoid tissues of PD mice.

CONCLUSIONPD has a dysfunction of peripheral immune system. It manifests enhancement of proinflammatory response and CD4+ T cell differentiation bias towards Treg cells away from Th1 cells.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine ; Animals ; CD4-Positive T-Lymphocytes ; pathology ; Cell Differentiation ; Cytokines ; blood ; Disease Models, Animal ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Interferon-gamma ; blood ; Interleukin-10 ; blood ; Interleukin-17 ; blood ; Interleukin-2 ; blood ; Interleukin-4 ; blood ; Interleukins ; blood ; Lymph Nodes ; cytology ; Lymphocyte Activation ; Mice ; Parkinson Disease ; immunology ; physiopathology ; Spleen ; cytology ; T-Box Domain Proteins ; metabolism ; T-Lymphocytes, Regulatory ; Th1 Cells ; Transforming Growth Factor beta ; blood

Animals ; Astrocytes ; immunology ; metabolism ; Male ; Microglia ; immunology ; metabolism ; Neurons ; metabolism ; Oxidopamine ; metabolism ; Parkinson Disease ; immunology ; Rats ; Rats, Sprague-Dawley

Parkinson's disease (PD) is a common degenerative disease of the central nervous system, but no drug has been found to be surely able to protect neurons so far, delay onset or slow progression of the disease. Currently there are a variety of Chinese formulas, single herb medicines, active fractions and monomers showed prophylactic and therapeutic effect on PD animal models. The mechanisms include protection of substantia nigra cells, improvement of neurotransmitter content, anti-oxidation, immune regulation, enhancement of Western medicine efficacy, reduction of side effects, etc. All these mechanisms may play integrated effect and slow disease progression. In particular, Chinese medicine compound may have some advantages in neuroprotective treatment of PD, because a variety of active ingredients can exert multi-links, multi-levels and multi-targets integrated regulation effect on human body. However, the level and standard of Chinese medicine studies on PD animal still need to be improved.
Animals ; Antioxidants ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Humans ; Medicine, Chinese Traditional ; methods ; Neuroprotective Agents ; pharmacology ; Parkinson Disease ; drug therapy ; immunology ; Substantia Nigra ; drug effects ; metabolism

Current hypothesis of neuronal degeneration in Parkinson's disease (PD) have been proposed, including formation of free radicals and oxidative stress, mitochondrial dysfunction, excitotoxicity, trophic factor deficiency, inflammatory processes, genetic factors, environmental impact factors, toxic action of nitric oxide, apoptosis, and so on. This review mainly discussed oxidative stress, environmental impact factors, and inflammatory processes in PD.
Animals ; Environmental Pollutants ; adverse effects ; Humans ; Inflammation ; immunology ; Oxidative Stress ; immunology ; Parkinson Disease ; immunology ; physiopathology

Inflammation, a self-defensive reaction against various pathogenic stimuli, may become harmful self-damaging process. Increasing evidence has linked chronic inflammation to a number of neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis. In the central nervous system, microglia, the resident innate immune cells play major role in the inflammatory process. Although they form the first line of defense for the neural parenchyma, uncontrolled activation of microglia may directly toxic to neurons by releasing various substances such as inflammatory cytokines (IL-1beta, TNF-alpha, IL-6), NO, PGE
alpha-Synuclein/physiology ; Signal Transduction ; Parkinson Disease/*etiology/immunology ; Multiple Sclerosis/etiology ; Models, Biological ; Microglia/immunology/metabolism/*physiology ; Metalloproteases/physiology ; Melanins/physiology ; Matrix Metalloproteinase 3 ; Inflammation Mediators/metabolism ; Humans ; Encephalitis/*etiology/immunology ; Cytokines/secretion ; Animals ; Alzheimer Disease/etiology ; AIDS Dementia Complex/etiology