A chemical called protease prolyl oligopeptidase (POP) is associated with schizophrenia, bipolar affective disorder, and, possibly, Alzheimer’s disease. In a previous study of Chinese herbs, baicalin, a flavonoid, was found to inhibit POP. Baicalin is found in Scutellaria baicalensis (skullcap) root.
The authors studied whether baicalin and it’s derivative, baicalein, would cross the intestinal barrier and would cross the blood/brain barrier (BBB.) The BBB protects the nervous system against harmful chemicals. The studies were done in the lab using an artificial permeable membrane assay. Baicalein is fat soluble and can cross both barriers. (Baicalin is water soluble.) The ability to be absorbed and cross the BBB is essential for treatment of psychiatric illness.
Baicalin is a prodrug used extensively in the past with few side effects. Baicalein is the chemical which, acturally, reaches the brain by crossing the BBB and can cross the gastrointestinal barrier. The usual dose of skullcap in Traditional Chinese Medicine (TCM) is 9 g., daily. The dose of baicalin, daily, is 78.4 mg.
Baicalein can inhibit HIV-1 replication, can inhibit harmful neurofibril formation and is anxiolytic (reduces anxiety.) The Chinese Traditional Medicine combination, Huang Lian Jie Du Tang, protects nerve cell death from lack of oxygen. This formula contains baicalin and berberine from Rhizoma coptidis (Coptis root.)
CONCLUSION: Baicalin, a flavonoid from skullcap, may be useful as therapy for schizophrenia, bipolar affective disorder and other neuropsychiatric problems because of POP enzyme inhibitor activity.
NOTE: Luteolin, berberine and quercetin are POP inhibitors. Rhizoma coptidis is the root of Coptis cinensis (coptis.) Read about skullcap as a natural inhibitor of angiogenesis in cancer.
To read the author’s abstract of the article click on the link to author’s title of the article above.