Hooshmand Mitra J, Galvan Manuel D, Partida Elizabeth, Anderson Aileen J
Institute for Memory Impairments and Neurological Disorders, University of California Irvine, 2001 Sue and Bill Gross Stem Cell Research, Irvine, CA 92697-4292, USA.
Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA.
Immun Ageing. 2014 Oct 29;11:15. doi: 10.1186/1742-4933-11-15. eCollection 2014.
Although the incidence of spinal cord injury (SCI) is steadily rising in the elderly human population, few studies have investigated the effect of age in rodent models. Here, we investigated the effect of age in female rats on spontaneous recovery and repair after SCI. Young (3 months) and aged (18 months) female rats received a moderate contusion SCI at T9. Behavioral recovery was assessed, and immunohistocemical and stereological analyses performed.
Aged rats demonstrated greater locomotor deficits compared to young, beginning at 7 days post-injury (dpi) and lasting through at least 28 dpi. Unbiased stereological analyses revealed a selective increase in percent lesion area and early (2 dpi) apoptotic cell death caudal to the injury epicenter in aged versus young rats. One potential mechanism for these differences in lesion pathogenesis is the inflammatory response; we therefore assessed humoral and cellular innate immune responses. No differences in either acute or chronic serum complement activity, or acute neutrophil infiltration, were observed between age groups. However, the number of microglia/macrophages present at the injury epicenter was increased by 50% in aged animals versus young.
These data suggest that age affects recovery of locomotor function, lesion pathology, and microglia/macrophage response following SCI.
尽管脊髓损伤（SCI）在老年人群中的发病率正在稳步上升，但很少有研究在啮齿动物模型中探究年龄的影响。在此，我们研究了年龄对雌性大鼠SCI后自发恢复和修复的影响。年轻（3个月）和老年（18个月）雌性大鼠在T9水平接受中度挫伤性SCI。评估行为恢复情况，并进行免疫组织化学和体视学分析。
与年轻大鼠相比，老年大鼠自损伤后7天（dpi）开始直至至少28 dpi均表现出更大的运动功能缺陷。无偏体视学分析显示，与年轻大鼠相比，老年大鼠损伤中心尾侧的损伤面积百分比和早期（2 dpi）凋亡细胞死亡选择性增加。损伤发病机制中这些差异的一个潜在机制是炎症反应；因此，我们评估了体液和细胞固有免疫反应。在不同年龄组之间，未观察到急性或慢性血清补体活性以及急性中性粒细胞浸润的差异。然而，与年轻动物相比，老年动物损伤中心的小胶质细胞/巨噬细胞数量增加了50%。
这些数据表明，年龄会影响SCI后的运动功能恢复、损伤病理以及小胶质细胞/巨噬细胞反应。
