Department of Nutrition, School of Public Health, University of Sao Paulo, Brazil.
Nutrients. 2011 Sep;3(9):792-804. doi: 10.3390/nu3090792. Epub 2011 Aug 31.
Glutamine, one of the most abundant amino acids found in maternal milk, favors protein anabolism. Early-weaned babies are deprived of this source of glutamine, in a period during which endogenous biosynthesis may be insufficient for tissue needs in states of metabolic stress, mainly during infections. The objective of this study was to verify the effects of dietary glutamine supplementation on the body composition and visceral protein status of early-weaned mice inoculated with Mycobacterium bovis Bacillus Calmette-Guérin (BCG). Mice were weaned early on their 14th day of life and seperated into two groups, one of which was fed a glutamine-free diet (n = 16) and the other a glutamine-supplemented diet (40 g/kg diet) (n = 16). At 21 days of age, some mice were intraperitoneally injected with BCG. Euthanasia was performed at the 28th day of age. BCG inoculation significantly reduced body weight (P < 0.001), lean mass (P = 0.002), water (P = 0.006), protein (P = 0.007) and lipid content (P = 0.001) in the carcass. Dietary glutamine supplementation resulted in a significant increase in serum IGF-1 (P = 0.019) and albumin (P = 0.025) concentration, muscle protein concentration (P = 0.035) and lipid content (P = 0.002) in the carcass. In conclusion, dietary glutamine supplementation had a positive influence on visceral protein status but did not affect body composition in early-weaned mice inoculated with BCG.
谷氨酰胺是母乳中含量最丰富的氨基酸之一,有利于蛋白质合成代谢。早期断奶的婴儿会失去这种谷氨酰胺来源,而在代谢应激状态下,内源性生物合成可能不足以满足组织需求,尤其是在感染期间。本研究的目的是验证膳食谷氨酰胺补充对感染牛分枝杆菌卡介苗(BCG)的早期断奶小鼠体成分和内脏蛋白状态的影响。小鼠在第 14 天断奶,并分为两组,一组喂食无谷氨酰胺饮食(n = 16),另一组喂食谷氨酰胺补充饮食(40 g/kg 饮食)(n = 16)。在 21 天时,一些小鼠被腹腔内注射 BCG。在第 28 天进行安乐死。BCG 接种显著降低了体重(P < 0.001)、瘦肉量(P = 0.002)、水分(P = 0.006)、蛋白质(P = 0.007)和脂类含量(P = 0.001)。膳食谷氨酰胺补充显著增加了血清 IGF-1(P = 0.019)和白蛋白(P = 0.025)浓度、肌肉蛋白浓度(P = 0.035)和脂类含量(P = 0.002)。总之,膳食谷氨酰胺补充对早期断奶的 BCG 接种小鼠的内脏蛋白状态有积极影响,但对体成分没有影响。