Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Avenida Professor Lineu Prestes, 580, Butantã, Sao Paulo, 05508-000, Brazil.
Department of Nutrition, Faculty of Public Health, University of Sao Paulo, Sao Paulo, Brazil.
Amino Acids. 2021 Apr;53(4):597-607. doi: 10.1007/s00726-021-02940-w. Epub 2021 Mar 14.
Although branched-chain amino acids (BCAA) are commonly used as a strategy to recover nutritional status of critically ill patients, recent findings on their role as immunonutrients have been associated with unfavorable outcomes, especially in obese patients. The present study aimed to explore the effects of different BCAA supplementation protocols in the inflammatory response of LPS-stimulated RAW 264.7 macrophages. Cell cultures were divided into five groups, with and without BCAA supplementation, (2 mmol/L of each amino acid). Then, cell cultures followed three different treatment protocols, consisting of a pretreatment (PT), an acute treatment (AT), and a chronic treatment (CT) with BCAA and LPS stimulation (1 µg/mL). Cell viability was analyzed by MTT assay, NO production was assessed by the Griess reaction and IL-6, IL-10, TNF-α and PGE2 synthesis, was evaluated by ELISA. BCAA significantly increased cell viability in AT and CT protocols, and NO and IL-10 synthesis in all treatment protocols. IL-6 synthesis was only increased in PT and CT protocols. TNF-α and PGE2 synthesis were not altered in any of the protocols and groups. BCAA supplementation was able to increase both pro and anti-inflammatory mediators synthesis by RAW 264.7 macrophages, which was influenced by the protocol applied. Moreover, these parameters were significantly increased by isoleucine supplementation, highlighting a potential research field for future studies.
尽管支链氨基酸（BCAA）通常被用作恢复危重症患者营养状况的策略，但最近关于它们作为免疫营养素的作用的发现与不良结局相关，尤其是在肥胖患者中。本研究旨在探讨不同 BCAA 补充方案对 LPS 刺激的 RAW 264.7 巨噬细胞炎症反应的影响。细胞培养分为五组，有无 BCAA 补充（每种氨基酸 2mmol/L）。然后，细胞培养遵循三种不同的处理方案，包括用 BCAA 和 LPS 刺激进行预处理（PT）、急性处理（AT）和慢性处理（CT）（1μg/mL）。通过 MTT 测定法分析细胞活力，通过格里斯反应评估 NO 产生，通过 ELISA 评估 IL-6、IL-10、TNF-α 和 PGE2 的合成。BCAA 在 AT 和 CT 方案中显著增加细胞活力，在所有处理方案中增加 NO 和 IL-10 的合成。IL-6 的合成仅在 PT 和 CT 方案中增加。在任何方案和组中，TNF-α 和 PGE2 的合成均未改变。BCAA 补充能够增加 RAW 264.7 巨噬细胞中促炎和抗炎介质的合成，这受到所应用方案的影响。此外，异亮氨酸补充显著增加了这些参数，这为未来的研究提供了一个潜在的研究领域。
