Comparison of Post-Ischemic Brain Injury in Young and Middle-Aged Stroke Rats

年輕及中年中風鼠缺血後腦部傷害的差異比較

張正一(Cheng-Yi Chang) ； 潘品合(Ping-Ho Pan) ； 林時逸(Shih-Yi Lin) ； 王雅瑜(Ya-Yu Wang) ； 陳文英(Wen-Ying Chen) ； 廖素蘭(Su-Lan Liao) ； 陳春榮(Chun-Jung Chen)

《童綜合醫學雜誌》 13卷2期 (2019/12) Pp. 75-82

https://doi.org/10.3966/207135922019121302003

摘要

Stroke is a disease of the elderly, and its incidence, disability, and mortality increase with age. Age-associated comorbidity is complex; thus, the exacerbation mechanisms of stroke injury in the elderly are multifactorial. To extend the scope of relevant studies, we aimed to investigate whether age and comorbidities are associated with severe post-ischemic brain injury and identified the factors involved in a rat model of stroke. Male adult Sprague Dawley rats at the age of 12 months (middle-aged) exhibited an endogenous environment that was more conducive to hyperlipidemia, hyperglycemia, hyperinsulinemia, insulin resistance, and chronic low-grade inflammation than rats at the age of 2 months (young). Middle-aged rats suffered from greater exacerbation of brain injury following cerebral ischemia than young rats when both the common carotid and the right middle cerebral arteries were clamped. The metabolic abnormalities of rats rendered them prone to ischemic brain injury, and post-ischemic brain injury in turn further augmented deleterious metabolic abnormalities. In conclusion, our results demonstrate that age-associated comorbidities such as hyperglycemia, insulin resistance, and chronic inflammation predispose rats to cerebral ischemia injury. The mechanisms of ischemic brain injury elucidated in our model of young and middle-aged rats with stroke could serve as the basis for further studies on this condition in the elderly.

關鍵字

Elderly ； Inflammation ； Metabolism ； Stroke

並列摘要

腦中風是老年人好發的疾病之一。腦中風的發生率、失能、死亡率會隨著年齡增長而上升。年齡相關的共病症複雜，顯示老年人的腦中風神經傷害高風險及惡化是多因性的作用結果。為了進一步擴展老年腦中風傷害惡化相關研究，本研究探討年齡與共病因子的腦中風神經傷害相關性及找尋牽涉的惡化因子。相對於2月齡（年輕）雄性Sprague-Dawley品系大鼠，12月齡鼠（中年），展現高血脂、高血糖、胰島素抗性、慢性低程度發炎的生理狀態。透過結紮雙側頸總動脈及右側中腦動脈的腦中風大鼠模式，實驗發現中年鼠的腦中風神經傷害嚴重度高於年輕鼠。中年鼠的代謝異常生理狀態促使腦中風後的神經傷害性增加。相對的，腦中風後的神經傷害也進一步惡化代謝異常。整體而言，我們的研究發現顯示，高血脂、高血糖、胰島素抗性、慢性發炎等年齡相關共病，促使中年大鼠的腦中風神經傷害性增加。以年輕及中年鼠腦中風模式所闡述的危害因子及神經傷害機制，將奠定後續老年腦中風相關的研究基礎。

並列關鍵字

老年 ； 發炎 ； 代謝 ； 中風