Alaverdashvili Mariam, Li Xue, Paterson Phyllis G
Neuroscience Research Group and College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
Neuroscience Research Group and College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
J Nutr. 2015 Nov;145(11):2503-11. doi: 10.3945/jn.115.216382. Epub 2015 Sep 30.
Adult protein-energy malnutrition (PEM) often occurs in combination with neurological disorders affecting hand use and walking ability. The independent effects of PEM on motor function are not well characterized and may be obscured by these comorbidities.
Our goal was to undertake a comprehensive evaluation of sensorimotor function with the onset and progression of PEM in an adult male rat model.
In Expt. 1 and Expt. 2, male Sprague-Dawley rats (14-15 wk old) were assigned ad libitum access for 4 wk to normal-protein (NP) or low-protein (LP) diets containing 12.5% and 0.5% protein, respectively. Expt. 1 assessed muscle strength, balance, and skilled walking ability on days 2, 8, and 27 by bar-holding, cylinder, and horizontal ladder walking tasks, respectively. In addition to food intake and body weight, nutritional status was determined on days 3, 9, and 28 by serum acute-phase reactant and corticosterone concentrations and liver lipids. Expt. 2 addressed the effect of an LP diet on hindlimb muscle size.
PEM evolved over time in rats consuming the LP diet. Total food intake decreased by 24% compared with the NP group. On day 28, body weight and serum albumin decreased by 31% and 26%, respectively, and serum α2-macroglobulin increased by 445% (P < 0.05) in the LP group compared with the NP group. Forelimb dysfunction (173% increase in adaptive flexed-arm-hang score) developed on day 2 in rats fed the LP diet (P < 0.001), whereas abnormal walking (34% decreased incidence of correct hindlimb placement) developed by day 27 (P < 0.05). Relative to the NP diet, the LP diet reduced the cross-sectional area of gastrocnemius medialis (P < 0.05).
PEM in adult male rats causes a variety of sensorimotor abnormalities that develop at different stages of malnutrition. This model can be used in combination with disease models of sensorimotor deficits to examine the interactions between nutritional status, other treatments, and disease progression.
成人蛋白质 - 能量营养不良（PEM）常与影响手部使用和行走能力的神经障碍同时出现。PEM对运动功能的独立影响尚未得到充分表征，且可能被这些合并症所掩盖。
我们的目标是在成年雄性大鼠模型中，随着PEM的发生和发展，对感觉运动功能进行全面评估。
在实验1和实验2中，将14 - 15周龄的雄性Sprague-Dawley大鼠随意分配，分别给予正常蛋白质（NP）或低蛋白质（LP）饮食4周，NP饮食含12.5%蛋白质，LP饮食含0.5%蛋白质。实验1分别在第2、8和27天通过握杆、圆筒和水平梯行走任务评估肌肉力量、平衡和熟练行走能力。除了食物摄入量和体重外，在第3、9和28天通过血清急性期反应物、皮质酮浓度和肝脏脂质来确定营养状况。实验2研究LP饮食对后肢肌肉大小的影响。
食用LP饮食的大鼠中PEM随时间演变。与NP组相比，总食物摄入量减少了24%。在第28天，LP组的体重和血清白蛋白分别下降了31%和26%，血清α2-巨球蛋白增加了445%（P < 0.05）。喂食LP饮食的大鼠在第2天出现前肢功能障碍（适应性屈臂悬垂评分增加173%）（P < 0.001），而到第27天出现异常行走（正确后肢放置发生率降低34%）（P < 0.05）。相对于NP饮食，LP饮食减少了腓肠肌内侧的横截面积（P < 0.05）。
成年雄性大鼠的PEM会导致多种在营养不良不同阶段出现的感觉运动异常。该模型可与感觉运动缺陷疾病模型结合使用，以研究营养状况、其他治疗方法和疾病进展之间的相互作用。
