L-methylfolate

A biologically active form of folate used in medical treatments

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L-methylfolate

Drug Information
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Identifiers ATC Code		Chemical Data C H N O Molecular Weight

L-methylfolate is the biologically active form of folate, a B-vitamin that is crucial for numerous bodily functions, including DNA synthesis and repair, cell division, and amino acid metabolism. It is the form of folate that can cross the blood-brain barrier, making it particularly important for neurological health.

Biochemistry

L-methylfolate, also known as 5-methyltetrahydrofolate (5-MTHF), is the predominant form of folate in the blood and is involved in the methylation cycle. It serves as a cofactor in the conversion of homocysteine to methionine, a reaction catalyzed by the enzyme methionine synthase. This process is critical for the production of S-adenosylmethionine (SAMe), a universal methyl donor involved in numerous methylation reactions, including the methylation of DNA, RNA, proteins, and lipids.

Medical Uses

L-methylfolate is used in the treatment of major depressive disorder (MDD) and schizophrenia, particularly in individuals with folate deficiency or genetic polymorphisms affecting folate metabolism, such as the MTHFR C677T mutation. It is also used as an adjunctive treatment in patients who do not respond adequately to antidepressants.

Depression

In patients with MDD, L-methylfolate supplementation has been shown to enhance the efficacy of selective serotonin reuptake inhibitors (SSRIs) and other antidepressants. It is believed to work by increasing the availability of neurotransmitters such as serotonin, dopamine, and norepinephrine in the brain.

Schizophrenia

L-methylfolate may also be beneficial in the treatment of schizophrenia, particularly in patients with elevated homocysteine levels or folate deficiency. It is thought to improve negative symptoms and cognitive deficits associated with the disorder.

Pharmacokinetics

L-methylfolate is well absorbed in the gastrointestinal tract and does not require conversion by the dihydrofolate reductase enzyme, unlike folic acid. This makes it a more effective form of folate for individuals with certain genetic polymorphisms that impair folate metabolism.

Safety and Side Effects

L-methylfolate is generally well tolerated, with a low risk of side effects. However, excessive intake can lead to insomnia, nausea, and gastrointestinal disturbances. It is important to use L-methylfolate under the guidance of a healthcare professional, especially in individuals with bipolar disorder, as it may exacerbate mania.

Also see

• Folate
• Folic acid
• MTHFR
• Homocysteine
• Major depressive disorder
• Schizophrenia