Li J, King B K, Janu P G, Renegar K B, Kudsk K A
Department of Surgery, University of Tennessee at Memphis 38163, USA.
JPEN J Parenter Enteral Nutr. 1998 Jan-Feb;22(1):31-6. doi: 10.1177/014860719802200131.
i.v. administration of a total parenteral nutrition (TPN) solution results in small intestinal gut-associated lymphoid tissue (GALT) atrophy, lowers small intestinal immunoglobulin A (IgA) levels, and impairs upper respiratory tract secretory IgA-mediated mucosal immunity; isonitrogenous supplementation of TPN with 2% glutamine attenuates these changes. This experiment examines whether a 2% glycyl-L-glutamine-enriched TPN solution reverses i.v. TPN-induced changes as effectively as L-glutamine.
Male Institute of Cancer Research (ICR) mice underwent intranasal inoculation with H1N1 influenza virus to establish immunity. After 3 weeks, mice were randomized to chow, i.v. feeding of a TPN solution, glutamine-enriched TPN, or glycyl-L-glutamine-enriched TPN. After 4 days of feeding, mice were challenged intranasally with influenza virus and killed at 40 hours to determine viral shedding from the respiratory tract; normal convalescent mice do not shed virus because they possess intact IgA-mediated mechanisms Lymphocytes were isolated from Peyer's patches, the intraepithelial layer, and lamina propria to determine cell yields.
Total lymphocyte yield in the Peyer's patches, the intraepithelial layer, and lamina propria decreased with TPN but remained normal with glutamine and glycyl-L-glutamine. Upon challenge, 70% of the mice in the TPN group shed virus in nasal secretions, whereas only 20% of the glutamine-treated group, 18% of glycyl-L-glutamine group and none of the Chow group were virus positive.
L-Glutamine and glycyl-L-glutamine have similar effects on i.v. administered TPN-associated (GALT) atrophy and decreased upper respiratory tract immunity.
静脉输注全胃肠外营养（TPN）溶液会导致小肠肠道相关淋巴组织（GALT）萎缩，降低小肠免疫球蛋白A（IgA）水平，并损害上呼吸道分泌型IgA介导的黏膜免疫；用2%谷氨酰胺对TPN进行等氮补充可减轻这些变化。本实验旨在研究2%甘氨酰-L-谷氨酰胺强化的TPN溶液是否能像L-谷氨酰胺一样有效逆转静脉输注TPN引起的变化。
雄性癌症研究所（ICR）小鼠经鼻接种H1N1流感病毒以建立免疫力。3周后，将小鼠随机分为正常饮食组、静脉输注TPN溶液组、谷氨酰胺强化TPN组或甘氨酰-L-谷氨酰胺强化TPN组。喂养4天后，经鼻用流感病毒攻击小鼠，并在40小时后处死以确定呼吸道病毒排出情况；正常恢复期小鼠不会排出病毒，因为它们具有完整的IgA介导机制。从派尔集合淋巴结、上皮内层和固有层分离淋巴细胞以确定细胞产量。
派尔集合淋巴结、上皮内层和固有层中的总淋巴细胞产量在TPN组降低，但在谷氨酰胺组和甘氨酰-L-谷氨酰胺组保持正常。攻击后，TPN组70%的小鼠鼻分泌物中排出病毒，而谷氨酰胺处理组仅20%、甘氨酰-L-谷氨酰胺组18%的小鼠病毒呈阳性，正常饮食组无一例病毒阳性。
L-谷氨酰胺和甘氨酰-L-谷氨酰胺对静脉输注TPN相关的（GALT）萎缩和上呼吸道免疫力下降具有相似的作用。
