New Study Suggests Mechanism Of Action For Botox In The Treatment Of Enlarged Prostate

"Most men consider an enlarged prostate and the irritating symptoms that accompany it as an inevitability of aging and may not seek help because currently available therapies can have serious side effects, including impotence," said Michael Chancellor, M.D., professor of urology at the University of Pittsburgh School of Medicine. "Alternative treatments are needed and we've taken an important step by demonstrating how Botox can work as a potential new therapy for the large number of men who suffer from this condition."

The research team had previously demonstrated that injection of Botox (botulinum toxin A) into the prostate gland produced improvement in symptoms such as the frequent urge to urinate, incomplete emptying of the bladder and low urine flow rate in men with bladder outlet obstruction due to BPH. The current study was conducted to investigate the mechanism of action by which Botox might work to reduce these symptoms.

For this study, researchers injected varying doses of Botox into the enlarged prostates of adult male rats. One week after injection, two types of altered cellular dynamics were observed, including an increase in apoptosis (cell death) and inhibition of cell proliferation, and down-regulation of adrenergic receptors in the prostate. Adrenergic receptors cause the contraction of the prostate and bladder muscles, making it difficult to void urine. By blocking these receptors, the muscles relax, allowing urine to flow more freely.

BPH is a non-cancerous growth of the prostate that can interfere with urination. It is one of the most common diseases affecting men, with current studies indicating that more than half of all men over the age of 60, and 80 percent of all men by age 80, will have enlarged prostates. Forty to 50 percent of the men who develop enlarged prostates will present with symptoms which include more frequent urination, urinary tract infections, the inability to completely empty the bladder, and, in severe cases, damage to the bladder and kidneys.

The study results were presented at the meeting as non-discussion poster # 237.