Anderson R, Lukey P T, Theron A J, Dippenaar U
Agents Actions. 1987 Feb;20(1-2):77-86. doi: 10.1007/BF01965628.
The effects of sodium ascorbate and cysteine (2.5 X 10(-5) M-2.5 X 10(-4) M) on the intensity and profile of luminol-enhanced chemiluminescence, superoxide generation, extracellular myeloperoxidase (MPO) activity and auto-iodination were measured in purified human polymorphonuclear leukocytes activated by the leukoattractant FMLP in vitro. Chemiluminescence studies were also performed using a whole-blood method. Cysteine (10(-4) M-2.5 X 10(-4) M) and ascorbate (2.5 X 10(-5) M-2.5 X 10(-4) M) caused significant inhibition of the early extracellular peak of FMLP-activated chemiluminescence and increased the intensity of the later occurring intracellular peak in both PMNL and blood. At the same concentrations both agents scavenged superoxide released by FMLP-activated PMNL, inhibited oxidant generation by extracellular MPO and decreased FMLP-induced auto-oxidation of PMNL. Administration of a single 1 gram oral dose of ascorbate to adult human volunteers was associated with significant reduction and enhancement respectively of the extracellular and intracellular luminol-enhanced chemiluminescence responses of FMLP-activated blood. These results show that the water soluble anti-oxidants cysteine and especially ascorbate selectively neutralise the reactivity of harmful reactive oxidants released by phagocytes, whilst the intracellular generation of antimicrobial oxidants remains intact.
在体外，通过白细胞趋化因子FMLP激活纯化的人多形核白细胞，测定了抗坏血酸钠和半胱氨酸（2.5×10⁻⁵M - 2.5×10⁻⁴M）对鲁米诺增强的化学发光强度和曲线、超氧化物生成、细胞外髓过氧化物酶（MPO）活性及自身碘化的影响。还采用全血法进行了化学发光研究。半胱氨酸（10⁻⁴M - 2.5×10⁻⁴M）和抗坏血酸盐（2.5×10⁻⁵M - 2.5×10⁻⁴M）显著抑制了FMLP激活的化学发光的早期细胞外峰，并增加了在多形核白细胞和血液中随后出现的细胞内峰的强度。在相同浓度下，两种试剂都清除了FMLP激活的多形核白细胞释放的超氧化物，抑制了细胞外MPO产生的氧化剂，并减少了FMLP诱导的多形核白细胞的自氧化。给成年人类志愿者口服单次1克剂量的抗坏血酸盐，分别与FMLP激活的血液的细胞外和细胞内鲁米诺增强的化学发光反应的显著降低和增强有关。这些结果表明，水溶性抗氧化剂半胱氨酸，尤其是抗坏血酸盐，选择性地中和了吞噬细胞释放的有害活性氧化剂的反应性，而细胞内抗菌氧化剂的产生保持完整。
