Arginase I is an enzyme that plays a crucial role in the urea cycle, which is responsible for removing excess nitrogen from the body. It catalyzes the conversion of arginine, an amino acid, into ornithine and urea. This process helps regulate nitrogen levels and is essential for maintaining metabolic balance. In addition to its role in the urea cycle, Arginase I is also involved in the immune response. It is produced by certain immune cells, where it can influence inflammation and tissue repair. Dysregulation of Arginase I activity has been linked to various health conditions, including cancer and cardiovascular diseases.