CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke.

OBJECTIVE: To study how the CD200-CD200R1 signaling pathway modulates poststroke inflammation and advances our knowledge of immune responses to ischemia insults in stroke. METHODS: Focal middle cerebral artery occlusion (MCAO) was induced in mice for 90 min, and mice were sacrificed at 1, 3, and 7 days of reperfusion. CD200, CD200R1, iNOS, and Arg-1 expression in ischemic brains was assessed by Western blotting (WB), and immunohistochemical (IHC) staining was performed to examine the expression of CD200 on neurons and CD200R1 on infiltrating lymphocytes. The severity of neurobehavioral deficits was evaluated by neurological deficit scores (NDS) and infarction volume estimated by TTC staining. To study the relationship between CD200/CD200R1 expression and the diversity of the neuroinflammatory response in stroke, CD200Fc (CD200R1 agonist) was subcutaneously injected at onset, at 1 day and 2 days after MCAO operation, and the brains were collected for detection at 3 days after MCAO/R (reperfusion). RESULTS: CD200 expression on neurons increased at 1 day and then decreased at 3 days after MCAO/R, and the expression of CD200R1 on lymphocytes showed an opposite temporal pattern as tested by IHC. The WB results showed that CD200/CD200R1 variance exhibited a similar pattern of IHC results, and the level of iNOS peaked at 1 day and then decreased gradually, but Arg-1 increased with time after MCAO/R in ischemic brains. After CD200Fc injection, CD200R1 expression significantly increased, and CD200Fc promoted Arg-1 but inhibited iNOS expression. The infarct volume and NDS of the group treated with CD200Fc were significantly smaller than those of the IgG2a-treated group. CONCLUSIONS: The CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke. Stimulation of CD200R1 by CD200Fc promotes the anti-inflammatory response and alleviates ischemic injury.

Assessment on dietary iodine intake in three areas of Zhejiang province, 2009 / 中华流行病学杂志

Objective To assess the level of dietary iodine intake in three areas of Zhejiang and the related policy on universal salt iodization in the province.Methods The study involved 497residents from 180 families living in Hangzhou,Taizhou,Zhoushan cities,representing coastal and inland areas in Zhejiang province in 2009.A total diet study was applied to obtain the typical diet samples at three study areas through food consumption,aggregation,sampling and preparation processes.The contents of iodine in diet samples were determined by tetramethylammonium hydroxide extraction-inductively coupled plasma-mass spectrometry.The amount of dietary iodine intake was calculated by timing the food consumption data and the iodine content in different dietary samples.The safety of dietary iodine intake was evaluated according to the recommended nutrient intake (RNI) and tolerable upper intake level (UL) published by the Chinese Nutrition Society in 2001.Results The dietary iodine intake of reference person in three areas of Zhejiang province was 421.0 μg/d.The levels of P5,P25,median,P75,P90,P95 dietary iodine intake were 145.7 μ g/d,267.6 μg/d,358.5 μg/d,495.6 μ g/d,774.1 μg/d and 1273.0 μg/d respectively.Daily dietary iodine intake at ＜RNI,RNI-UL,＞UL accounted for 5.2％,87.5％ and 7.2％ of all the participants respectively.Without considering the loss through cooking,salt iodine provided 81.6％ of the dietary iodine source.The resources of dietary iodine would include vegetables,cereals and marine food,proportionally,as 57.2％,13.0％ and 8.5％,respectively.Participants whose daily dietary iodine intake exceeded the UL level would consume more marine algae products than those whose dietary iodine intakes were lower than RNI or between RNI-UL.Conclusion Dietary iodine intake among most residents and their average level were among reasonable ranges.Meanwhile,deficiency and excess of iodine intake coexisted.Salt iodine was the main resource of dietary iodine.Participants whose dietary iodine intakes exceeding the UL level,would prefer consume more marine algae products.