Enzymic degradation of plasma arginine using arginine deiminase inhibits nitric oxide production and protects mice from the lethal effects of tumour necrosis factor α and endotoxin

Abstract

Septic shock is mediated in part by nitric oxide (NO) and tumour necrosis factor alpha (TNFalpha). NO is synthesized primarily from extracellular arginine. We tested the ability of an arginine-degrading enzyme to inhibit NO production in mice and to protect mice from the hypotension and lethality that occur after the administration of TNFalpha or endotoxin. Treatment of BALB/c mice with arginine deiminase (ADI) formulated with succinimidyl succinimide polyethylene glycol of M(r) 20000 (ADI-SS PEG(20000)) eliminated all measurable plasma arginine (from normal levels of approximately 155 microM arginine to 2 microM). In addition, ADI-SS PEG(20000) also inhibited the production of NO, as quantified by plasma nitrate+nitrite. Treatment of mice with TNFalpha or endotoxin resulted in a dose-dependent increase in NO production and lethality. Pretreatment of mice with ADI-SS PEG(20000) resulted in increased resistance to the lethal effects of TNFalpha and endotoxin. These observations are consistent with NO production resulting, to some extent, from the metabolism of extracellular arginine. The toxic effects of TNFalpha and endotoxin may be partially inhibited by enzymic degradation of plasma arginine by ADI-SS PEG(20000). Interestingly, pretreatment with ADI-SS PEG(20000) did not inhibit the anti-tumour activity of TNFalpha in vitro or in vivo. This treatment may allow greater amounts of TNFalpha, as well as other cytokines, to be administered while abrogating side effects such as hypotension and death.

Incidence and distribution of argininosuccinate synthetase deficiency in human cancers

“…A once-a-week injection of this enzyme in mice and humans is sufficient to eliminate all detectable arginine from the circulation (data not shown) and to block nitric oxide production. 12,27,28 This treatment is well tolerated in mice and preliminary results from human clinical testing indicate that this therapy is also well tolerated in humans. The initial clinical testing of this drug is limited to patients with melanoma and HCC because of the high incidence of ASS deficiency observed in these tumors.…”

Arginine deiminase: a potential inhibitor of angiogenesis and tumour growth

“…In fact, at least three enzymes destroy arginine. The second enzyme is arginine decarboxylase (Philip et al, 2003), and the third is ADI, which we recently showed to have the ability to deplete plasma arginine and suppress LPS-induced NO production, suggesting a potential inhibitory role of ADI in NO-mediated angiogenesis (Noh et al, 2002;Thomas et al, 2002). Wilm et al (1996) purified a protein that strongly inhibited proliferation of vascular endothelial cells, later identified as ADI from Mycoplasma.…”

Immunosuppressive Effects of Arginine Deiminase From Streptococcus Pyogenes

“…Большинство клеток млекопитающих, вклю-чая гранулоциты, эритроциты, гепатоциты, ми-елоидные супрессорные клетки, тучные клет-ки, эндотелиальные клетки и гладкомышечные клетки, обладают в разной степени выраженной аргиназной и NOS активностью [101]. NOS мета-болизируют внутриклеточный аргинин с продук-цией цитрулина и оксида азота.…”

“…Данные об экспрессии ферментов, метаболизирующих аргинин, в моноцитах/ма-крофагах человека зачастую противоречат друг другу, что, вероятно, связано с разными методами выделения, разной тканевой принадлежностью, а также с разными способами культивирования и активации этих клеток. Значительно отлича-ются и методы детекции ферментов, а именно -в разных исследованиях изучается их экспрессия на уровне РНК, на уровне белка или же биоло-гическая активность [36,94,95,101]. Более того, в литературе высказываются сомнения относи-тельно важности этих ферментов как маркеров классической и альтернативной активации ма-крофагов человека [72].…”