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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Inter-basin water transfer (IBWT) involves the transport of water from one geographically distinct basin to another to balance the distribution of water resources. Although the socio-economic benefits of implementing these projects are well recognized, little is known about the subsequent effects on the water quality of the receiving systems. We evaluated the effects of an IBWT on the water quality of three receiving reservoirs of an intermittent river in a semi-arid region. We compared the similarity among the reservoirs before and after the IBWT to assess how the reservoirs responded to the introduction of water. Although the last two reservoirs that have received water have become similar in terms of physical and chemical characteristics and algal biomass (chlorophyll-a), the first reservoir has not. The IBWT resulted in an improvement in the water quality of the first reservoir but a decrease in the water quality of the two successive reservoirs, along with a significant increase in algal biomass. Long river sections located upstream that were dry at the time of IBWT probably contributed nutrients to the water as it moved downstream and into the reservoirs. Significant differences in the water quality were observed for different sampling months after the IBWT, but not for different sampling depths. Before the IBWT, the predictor variables for algal biomass were basically transparency and non-algal turbidity, with which it established a positive relationship. After IBWT, however, algal biomass also showed a positive relationship with pH and temperature. We conclude that IBWT affects the water quality of receiving reservoirs and that the responses are reservoir specific. IBWT also increases the complexity of the correlations of physical and chemical variables with algal biomass.
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