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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.
相似文献The Atlantic Forest is one of the most threatened tropical forests in the world, being drastically reduced, fragmented, and disturbed. The drastic process of anthropic occupation and exploitation of this biome has, in many cases, led to the introduction of exotic species, such as the jackfruits (Artocarpus heterophyllus). However, studies on the influence of jackfruits on the native biota are still scarce. Here we investigated the influence of fruit trees on the seed rain and early recruitment of seedlings in native remnants, comparing these patterns with those observed for a native species tapirira (Tapirira guianensis), which similarly to jackfruits, produces many fruits throughout the year, attracting a variety of frugivore species. Seed rain and seedlings observed under the jackfruits were both more abundant and equally rich to the assemblages reported under the native tapirira trees. In both species, co-specifics comprise a large part of the number of seeds (>?70%) and seedlings (>?45%) individuals and, although they attract similar seed assemblages, seedling composition diverge, particularly when co-specifics are excluded. We reported that jackfruits can attract a diverse seed and seedling assemblages, and we find no evidence that the presence of jackfruits negatively affects the arrival and initial recruitment of native plant species in the study area. These results should be analyzed with caution but considered when evaluating costs and benefits of management options to control exotic species.
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