Bodybuilders, power lifters and other strength athletes may be able to build up more muscle if they eat a portion of cabbage-related vegetables every day. Brassicas such as cauliflower, broccoli and sprouts all contain the compound sulforaphane. Molecular scientists at the University of Bonn have discovered that this deactivates the muscle growth inhibitor myostatin in satellite cells – and therefore may also have an anabolic effect. The results of their study have been published in Epigenetics.
Sulforaphane & muscles
It’s nothing new that sulforaphane is of interest to strength athletes. The popular scientific website Ergo-Log – modest ahem – speculated a year ago already about this after Italian researchers had discovered that sulforaphane improved the survival chances of one type of stem cell that is capable of developing into muscle cells.
The Italian findings were unexpected. Nutritionists have had their eye on sulforaphane for a while, but had been concentrating on a different health effect: on its ability to boost detoxification and possible anti-carcinogenic effect.
Well, the researchers in Bonn did experiments on satellite cells taken from the muscles of pigs. Pigs’ cells bear a remarkable resemblance to human cells. Satellite cells are found in muscle tissue and develop into adult muscle cells when given the right stimuli.
The researchers exposed the pig satellite cells to sulforaphane [SFN] in test tubes, using concentrations of 5, 10 and 15 micromoles, and observed that the lowest dose [SFN 5] increased the vitality of the cells and reduced the synthesis of suicide proteins such as caspase-3 and -9. This is interesting, because in cancer cells sulforaphane has completely the opposite effect: sulforaphane actually reduces vitality in cancer cells and activates the suicide mechanism.
Sulforaphane dramatically reduced the production of myostatin [MSTN] in the satellite cells, as shown above. The researchers are not sure why this was the case. They did check whether sulforaphane boosted the synthesis of follistatin [FST], a protein that can deactivate myostatin, but this was not the case.
The researchers have high expectations of the muscle strengthening effect of sulforaphane. “If its effects are verified and applied to in vivo models, sulforaphane may have therapeutic benefits in the treatment of human skeletal muscle disorders and practical value in meat production”, they write.
The best natural sources of sulforaphane are fresh broccoli and Brussels sprouts. Tinned cabbage and prepared cabbage in plastic packaging do not contain much sulforaphane. Bodybuilders who want to start experimenting with sulforaphane right away can of course use natural supplements.
Strictly speaking cabbage-type vegetables don’t contain sulforaphane, but do contain glucoraphanin [structural formula shown below]. Cutting up, chewing and digesting cabbage-type vegetables converts glucoraphanin into sulforaphane [structural formula on right below].
Epigenetics. 2012 Dec 1;7(12):1379-90.