Folihappovastainen

Folihappovastainen refers to substances that inhibit or block the action of folic acid. Folic acid, also known as vitamin B9, is essential for various bodily functions, including DNA synthesis and repair, cell division, and the production of red blood cells. Substances that are folihappovastainen can interfere with these processes.

One of the most well-known examples of a folihappovastainen compound is methotrexate. Methotrexate is a chemotherapy drug and an immunosuppressant used to treat various cancers, autoimmune diseases like rheumatoid arthritis, and psoriasis. It works by inhibiting dihydrofolate reductase (DHFR), an enzyme that converts dihydrofolate into tetrahydrofolate, the active form of folic acid. By blocking this conversion, methotrexate depletes the body's supply of tetrahydrofolate, thus hindering DNA synthesis and cell proliferation, particularly in rapidly dividing cancer cells and immune cells.

Another class of folihappovastainen agents includes certain antibiotics, such as trimethoprim. Trimethoprim is often used in combination with sulfamethoxazole to treat bacterial infections. It also targets the bacterial form of DHFR, inhibiting folic acid synthesis in bacteria, which is crucial for their survival and reproduction. Because human DHFR has a much lower affinity for trimethoprim than bacterial DHFR, it acts as a selective inhibitor.

Antifolate medications can have significant side effects due to their interference with normal cell processes. These can include bone marrow suppression, leading to anemia, low white blood cell count, and low platelet count, as well as gastrointestinal issues and mucositis. For this reason, patients taking these medications are often monitored closely, and folic acid supplements may sometimes be prescribed alongside them to mitigate some of the side effects, particularly with long-term use of certain agents like methotrexate.