Modulated Colonic Oxidative Stress Markers and Clinical Parameters: A Potential Adjuvant Therapy to Manage Side Effects During 5-FU Regimen.

One of the most used chemotherapy agents in clinical practice is 5-Fluorouracil (5-FU), a fluorinated pyrimidine in the category of antimetabolite agents. 5-FU is used to treat a variety of cancers, including colon, breast, pancreatic, and stomach cancers, and its efficacy lies in its direct impact on the patient's DNA and RNA. Specifically, its mechanism blocks the enzymes thymidylate synthetase and uracil phosphatase, inhibiting the synthesis of uracil, which cannot be incorporated into nuclear and cytoplasmic RNA. Despite being one of the most used drugs in oncology, it is associated with several significant side effects, including inflammation of the mouth, loss of appetite, and reduction in blood cells. In our study, we examined the reduction of side effects in a 5-FU regimen administered at doses of 15 mg/kg and 6 mg/kg for 14 days in 6-week-old male Sprague-Dawley rats. On the 14th day, the rats were treated orally for 2 weeks with 100 mg/kg of , a well-known seaweed from the Ulvaceae family, which has demonstrated powerful biological properties. The administration of this green alga alleviated the side effects of 5-FU, improving several parameters including body weight, food intake, and diarrhea index. It also helped reduce side effects in the blood, kidneys, and liver. Histological and molecular analyses were conducted on serum and colon tissues from the rats, examining changes in colon structure and the release of oxidative stress markers such as iNOS, COX-2, and nitrotyrosine. Several biochemical indicators, including SOD, CAT, GSH, MDA, and ascorbic acid, were also evaluated. Overall, our data indicated to be a promising therapeutic against 5-FU's adverse effects, therefore, it could be worthwhile to investigate the possibility of using this alga in safer cancer treatment formulations. Certainly, future preclinical and clinical studies could assess the alga's efficacy in diverse cancer treatment regimens, exploring its role as an adjuvant therapy that may reduce chemotherapy-related toxicity without compromising therapeutic outcomes.