The abstract is here is you are interested: Anabolic effect of plant brassinosteroid
It is an interesting study. It is in rats, so as usual be careful with it, but the researchers suggest that:
"HB has a different mode of action from anabolic steroids in that it doesn’t seem to have an effect on male hormones; this may suggest to readers that plant-derived steroids could be considered acceptable for use where anabolic steroids are not."Very interesting.
There is more discussion at the NHS choices site which disects health stories in the news.