Adapala Nagasuresh, Chan Marion M
Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, PA 19140, USA.
Lab Invest. 2008 Dec;88(12):1329-39. doi: 10.1038/labinvest.2008.90. Epub 2008 Sep 15.
Inflammation is considered the underlying cause of numerous disorders, and the practice of taking antiinflammatories as diet supplements has become increasingly prevalent. This study addresses the bioavailablity of a well-established dietary antiinflammatory, curcumin, and examines its effect on adaptive immunity. Visceral leishmaniasis is a major parasitic disease which protection relies on cell-mediated immunity and production of nitric oxide. We found that long-term, low-dose, oral consumption of curcumin activates peroxisome proliferator-activated receptor-gamma, deactivates type 1 response, inhibits inducible nitric oxide synthase, and interferes with adaptive immunity to exacerbate the pathogenesis of Leishmania donovani infection in vivo. These in vivo effects can be correlated to activities on infected residential macrophages in vitro. Therefore, when reactive radicals generated from inflammation play the dominant role in elimination of pathogens, excessive use of the antioxidative supplements may compromise microbial defense. Nonetheless, it should be noted with equal importance that our finding, conversely, also strengthens the prospect that curcumin may alleviate type 1 response disorders.
炎症被认为是众多疾病的根本原因，将抗炎药作为膳食补充剂的做法越来越普遍。本研究探讨了一种公认的膳食抗炎剂姜黄素的生物利用度，并研究了其对适应性免疫的影响。内脏利什曼病是一种主要的寄生虫病，其保护依赖于细胞介导的免疫和一氧化氮的产生。我们发现，长期、低剂量口服姜黄素会激活过氧化物酶体增殖物激活受体γ，使1型反应失活，抑制诱导型一氧化氮合酶，并干扰适应性免疫，从而在体内加剧杜氏利什曼原虫感染的发病机制。这些体内效应与体外对受感染驻留巨噬细胞的作用相关。因此，当炎症产生的活性自由基在病原体清除中起主导作用时，过度使用抗氧化补充剂可能会损害微生物防御。然而，同样重要的是应该注意到，相反，我们的发现也增强了姜黄素可能缓解1型反应紊乱的前景。
