New insights on the molecular mechanisms of collateral sprouting after peripheral nerve injury

Axonal regeneration after injuries to the nervous system has been extensively studied due to its implication in motor and sensory functional recovery. Distinct types of regeneration has been identified, such as canonical axonal regeneration, defined as the growth of axons from the transected axonal stump to reinnervate the original target, or regenerative sprouting, in which the growth occurs from a region of the damaged axon either close or far from the injury site(Tuszynski and Steward, 2012).

一种中药单体小复方对变应性鼻炎模型小鼠的免疫调节作用

目的:探讨3种中药单体淫羊藿苷、黄芩苷、黄芪甲苷经优化配比组成的小复方对变应性鼻炎模型小鼠的免疫调节作用。方法:采用卵清蛋白腹腔注射与滴鼻结合的方法建立变应性鼻炎小鼠模型,分离小鼠脾淋巴细胞后体外培养,并将细胞分为空白对照组、刀豆素A组、复方组3组,在不同时间点运用细胞增殖-毒性检测试剂盒连续观察各组细胞的增殖情况,流式细胞术检测各组细胞周期变化,荧光定量分析仪结合荧光探针Fluo-3检测细胞内游离钙离子浓度变化。结果:中药单体小复方可以有效抑制刀豆素A诱导的变应性鼻炎小鼠脾淋巴细胞增殖(P<0.01),且呈现出一定的时效关系,抑制率随时间的延长而增强,在48h达最大值。流式细胞术检测各组细胞的细胞周期变化发现,刀豆素A可以通过降低G0/G1期百分比,升高S期与G2/M期的百分比而促进细胞进入分裂期,复方组与刀豆素A组相比,则在4个时间点均可以升高G0/G1期比例,并降低S期与G2/M期的比例,作用在24h最显著(P<0.05或P<0.01)。荧光定量分析仪检测发现,前24h,刀豆素A诱导后的淋巴细胞荧光强度随时间延长而逐渐增强,而复方组可以明显抑制刀豆素A导致的荧光强度升高,降低细胞内游离钙离子浓度(P<0.01)。结论:中药单体小复方可以抑制刀豆素A诱导的变应性鼻炎模型小鼠脾淋巴细胞增殖,其作用机制可能为通过降低细胞内游离钙离子浓度,从而抑制细胞由G0/G1期进入S和G2/M期。