Nolvadex rejuvenates blood vessels

Chemical athletes who use the anti-oestrogen nolvadex may also be making their blood vessels more healthy, and reducing their risk of a fatal heart attack. We deduce this from a trial done by researchers in Cambridge, England that was published eight years ago in Circulation.

The active ingredient in preparations like nolvadex is tamoxifen [structure shown here]. Nolvadex is a SERM: a compound that is capable of attaching itself to the receptor for the female sex hormone estradiol. What’s more, nolvadex is an anti-oestrogen. The compound forces estradiol off its receptor, thereby preventing estradiol from doing its work. Nolvadex then sits in the estradiol receptor a bit like a key that has broken off in a lock. No other key can be put in the lock, but the door won’t open either. Athletes use nolvadex to counter the side effects of oestrogens, which are produced when testosterone is converted into estradiol. Nolvadex is also used after taking a course of steroids to boost the body’s own testosterone production.

In the British study, 30 men with furred up arteries were given 40 mg of nolvadex every day for 56 days. The researchers wanted to know more about the effect of nolvadex on the heart and the blood vessels. Estradiol has good and bad effects on the heart and arteries. It increases the amount of ‘good cholesterol’ HDL, which is positive. But it also causes blood clots, which is not such good news.

The men’s testosterone levels rose, and their estradiol levels rose too. Apparently the conversion of testosterone into estradiol simply continued.

NCA = 10 male patients with a history of chest pain suggestive of angina pectoris but with normal coronary angiograms. TVD = men with a triple-vessel disease, i.e. clogged up arteries in the heart. This group was given statins and aspirin.

The researchers used a complicated procedure to measure the elasticity of the men’s blood vessels [ED-FMD]. In the graph below you can see that the nolvadex treatment increased the elasticity.

If you’re healthy and under 40, then you probably have an ED-FMD of 7 percent. As you get older your ED-FMD declines to around 5 percent by the age of 51. At your ED-FMD is 3.5 percent. The NCA group had an average age of 51. The average age of the TVD group was 63. So the cardiovascular age of the men decreased.

The figure below shows more cardiovascular parameters.

Most effects are favourable. Lipoprotein (a) is a building block of the ‘bad’ LDL cholesterol. The more of this you have in your blood, the more worried the cardiologists get. The lower the amount of triglycerides and LDL in your blood, the better. They both have an adverse effect on the HDL.

All in all, the researchers were pleasantly surprised by the results of their research. "The data provide strong evidence to support clinical evaluation of SERMs for the treatment of men with CAD", they write in the last sentence of their article.

Circulation. 2001 Mar 20;103(11):1497-502.