The effectiveness of the drug against Alzheimer's disease has not been confirmed
Bexarotene does not help with Alzheimer's disease
ABC Magazine based on Nature: Studies cast doubt on cancer drug as Alzheimer's treatment
Last year, the journal Science published the stunning results of a study by a neurologist from the Case Western Reserve University School of Medicine in Cleveland, according to which the oncological drug bexarotene is able to treat Alzheimer's disease. However, four independent groups of scientists who repeated this study failed to obtain the same amazing results, which calls the conclusions of the first study into question. The scientists' articles are also published in the journal Science.
According to an initial study by Gary Landreth and his colleagues, bexarotene reduces the concentration of beta-amyloid in the brain, the deposits of which are considered the main cause of the development of Alzheimer's disease. According to the authors, in just 72 hours after the introduction of bexarotene, the number of amyloid plaques decreases by 2 times. Moreover, the results of the study showed that the drug is able to restore cognitive impairment in mice with this disease.
These loud statements attracted the attention of many scientists to the study. Many of them wanted to repeat this study and verify the effectiveness of bexarotene, since none of the known drugs is yet able to have such a therapeutic effect. However, none of the four groups of researchers managed to get the same results as Landreth's team. However, two groups confirmed that the drug does reduce the level of free-form beta-amyloid, which can stick together into plaques. One group also confirmed some improvements in cognitive abilities in mice after a course of treatment with bexarotene.
Mr. Landreth himself is extremely surprised by the failure of his colleagues. He suggests that the researchers could have used a different method of preparation of the drug, which affected its concentration in the brain or even changed its biological activity. The neurologist emphasizes that the two results he obtained were nevertheless reproduced — a decrease in the concentration of free beta-amyloid and an improvement in cognitive impairment. Moreover, the scientist considers the first fact to be the most important, since recent studies suggest that the main role in the development of Alzheimer's disease is played not by already formed plaques, but by the concentration of free beta-amyloid in the blood.
Researchers whose work did not confirm Landreth's result warn that until clinical studies, reliable evidence and clarification of the exact mechanism of the effect of bexarotene on the concentration of beta-amyloid, patients with Alzheimer's disease should not count on the real help of this drug. It is especially important to convey this to patients so that they do not rush to buy the drug, since it is already registered on the US pharmaceutical market. Dr. Landreth, in turn, announced that he is starting a clinical study of the effectiveness of bexarotene for the treatment of Alzheimer's disease.
Portal "Eternal youth" http://vechnayamolodost.ru28.05.2013