Inactivation of microglia dampens blood-brain barrier permeability and loss of dopaminergic neurons in paraquat-lesioned mice.

Prior studies indicated the involvement of neuroinflammation in the dopaminergic neurodegeneration in mice of paraquat (PQ)-induced Parkinson's disease (PD), but the underlying mechanisms remain to be elucidated. The present study explored whether microglia-mediated inflammation disrupted blood-brain barrier (BBB) and its related mechanism. C57BL/6 mice were injected intraperitoneally with PQ, twice a week for six weeks, following with or without minocycline (intraperitoneal injection, once every two days). The microglial activation, BBB permeability, expression of tight junctions (TJs) proteins and matrix metalloproteinase (MMP), as well as the loss of dopaminergic neurons and neurological deficits assessment, were evaluated. Minocycline efficiently restrained nigral microglial activation induced by PQ in mice. PQ-induced increase of EB content in the brain and excessive expression of zonula occludin-1 (ZO-1), claudin-5 and occludin were significantly dampened by minocycline treatment. Inhibition of microglial activation by minocycline greatly ameliorated the loss of dopaminergic neurons and neurological dysfunctions in PQ-exposed mice. Also, microglial inactivation downregulated the expression of MMP-2/9 in PQ-lesioned mice. These findings suggested the potential protection of suppressing microglia-mediated neuroinflammation against dopaminergic neurodegeneration through attenuating BBB disruption in a mouse of PQ-induced PD, and MMP-2/9 might involve in the contribution, which needs to be verified in future study.

[Hepatitis viruses infection situation in human population of the Gansu province].

OBJECTIVE: To investigate the seroprevalence of hepatitis viruses in human population of Ganso province. METHODS: ELISA was used for detecting anti-HAY IgG, HBsAg/HBsAb, anti-HCV IgG and anti-HEV IgG of the serum samples. All sample were collected in four areas of KL, LT, HN and ZhL of Gansu province in 2008. RESULTS: 1977 samples were detected, The positive rates of anti-HAY, HBsAg/HBsAh, anti-HCV, and anti-HEY are 84.57% (1672/1977), 4.81% (95/1977) and 28.73% (568/1977), 0.46% (9/1977),and 13.10% (259/1977), respectively. The positive rate at different age group, for anti-HAY was 43.21% of c 9 years old, 80.23% of 10-19 years old, 93.02% of 20-29 years old, 95.55% of 30-39 years old, 95.60%-97.52% of 40-60 years old. For HBsAg/HBsAb were 2.09% or 29.27%, 3.02% or 21.81%, 6.20% or 36.43%, 5.93% or 31.16%, 6.43% or 3l.43%, 7.32% or 24.88%, 3.33% or 28.89% at the same age group, respectively, for anti-HCV, was 0.59% of 30-39 years old, 1.79% of 40-49 years old, 0.98% of 50-59 years old. For HEY-IgG was 3.48% of < or =9 years old, 6.05% of 10-19 years old, 8.53% of 20-29 years old, 19.29%-21.67% of 30- > or =60 years old. CONCLUSIONS: The inoculation againt HAY and HBY is enhanced in the youngster population. HBsAg carrier and UCY infection is decreasing. The HEY infection in the Hid people is lower than the Han nationality.