The Effect of Arginine Intake on Colorectal Cancer: a Systematic Review of Literatures.

Colorectal cancer (CRC) is one of the major reasons of mortality in the worldwide. There is clear evidence that some amino acids such as arginine can improve CRC and its complications. Hence, in this systematic review we evaluated the association between arginine intake and CRC improvement. We searched the PubMed, Scopus, ISI Web of Science, Cochrane library, and Google Scholar databases by using proper keywords to find the relevant literatures, published to March 2019. Nine human studies of 523 screened articles were included in present systematic review. The majority of studies have found a positive association between consumption of arginine and CRC improvement. Increased inducible nitric oxide (NO) synthase expression and subsequently increasing the NO concentration in the tumor and/or serum, after arginine intake may be responsible for these protective effects. Also, arginine consumption may reduce cell proliferation in CRC and it can enhance immune function after remove the tumor. Although the benefits of arginine consumption in CRC patients were reported in previous trials, the finding need replication in well-designed studies before final conclusion.