Arginine
Summary:
L-Arginine is a conditionally essential amino acid. It
stimulates the immune system by
increasing the output of T lymphocytes (T- cells) from the thymus gland. Recent
studies have focused on the potential of arginine as a treatment for AIDS,
cancer, and other diseases linked to a depressed immune system.
It plays a vital role in protein synthesis, healing and repair of damaged
tissues, and the regulation of insulin, growth hormone and vasopressin (which
regulates vascular tone). It also helps detoxify the liver by neutralizing
ammonia
and other toxic substances in the body. It is
vital to the pathways that produce ornithine, citrulline and nitric oxide (a
regulator of tumor proliferation and expression). Rich sources are wheat germ,
whole wheat, nuts and seeds, soy protein and other plant proteins. Typical
dietary intake is 3.5-5 grams daily. (For more detailed information, please
visit ISM’s searchable database:
Nutraceutical Search.)
Abstracts
GENERAL CANCER
The concentration of 21 amino acids was measured in the venous plasma of 41 patients with cancer of the gastrointestinal tract who had lost weight……. The concentration of the amino acid arginine was significantly greater in patients with cancer both with weight loss and without weight loss……. This was in contrast with the rise in plasma arginine in patients with pyloric stenosis after surgery, suggesting that the raised level of arginine was due to the presence of the primary tumour.
o Glass, RE, Goode, AW, Houghton, BJ, & Rowell, LW (1986). Plasma arginine in cancer of the gastrointestinal tract: effect of surgical treatment. Gut, 27, 844-8.
A significantly increased whole muscle protein synthesis rate was noticed with arginine supplementation in tumour bearing rats. Muscle concentrations of arginine, ornithine, glutamine, and glutamate were considerably higher.
o JPEN J Parenter Enteral Nutr. 1994 Nov-Dec; 18(6): 491-6.
Malignant tumors associated with various degrees of metabolic derangements are all associated with decreased plasma arginine concentrations, even without weight loss. This suggests that decreased arginine availability is a specific feature of the presence of cancer. These disturbances in arginine metabolism could contribute to the cascade of metabolic events leading to cancer cachexia.
o Vissers, YLJ et al (2005).Plasma arginine concentrations are reduced in cancer patients: evidence for arginine deficiency?. Am J Clin Nutr, 81(5), 1142-6.
Arginine supplementation augments both specific and nonspecific anti-tumor mechanisms, retards tumor growth, and prolongs survival in some animal tumor models.
o American Journal of Critical Care. 2004; 13: 17-23.
The discovery that L-arginine is the sole precursor for the multifunctional messenger molecule nitric oxide (NO) led to investigation into the role of arginine in numerous physiologic and pathophysiologic phenomena including cancer. Although NO was first identified in endothelial cells, it is now recognized to be generated by a variety of cell types, including several tumor cell lines and solid human tumors….. A better understanding of the role of arginine-derived NO in cancer may lead to novel antineoplastic and chemopreventative strategies.
o Lind, DS (2004).Arginine and Cancer. J Nutr, 134, 2837-41.
There is a growing interest in the role of arginine in cancerogenesis, since this amino acid has turned out to be absolutely essential for growth of neoplastic cells. It also plays a crucial role in biosynthetic pathways that significantly influence carcinogenesis and tumor biology. They include synthesis of polyamines and nitric oxide, important molecules, which may be synthesized solely from arginine. These findings have resulted in first clinical trials on arginine deprivation in therapy of some arginine-dependent (auxotrophic) tumors.
o Graboń, W (2006).Arginine as a crucial amino acid in carcinogenesis and tumor growth. Postepy Hig Med Dosw , 60, 483-9.
Although it is self evident that cells will not grow in amino acid deficient medium, an observation less well appreciated is that malignant cells are particularly vulnerable to such deprivation, which can lead to their rapid demise…..It is argued that current knowledge, combined with past experience, calls for a much closer examination of the full potential of amino acid (and specifically arginine) deprivation as a means of controlling tumor growth, with greater attention to protocols that might be used to treat human cancers.
o Wheatley, DN, & Campbell, E (2002). Arginine catabolism, liver extracts and cancer. Pathol Oncol Res, 8(1), 18-25.