As you may have heard on the podcast, the most significant finding of the Ravussin study (Ravussin. 2011) was the down-regulation of pro-opiomelanocortin [POMC] neurons in the hypothalamus, which went hand in hand with weight gain and weight loss and is associated with a reduction of the metabolic rate to levels at which further weight loss or even weight maintenance become a significant challenge. Here, the findings of the aforementioned study on royal jelly, "a honey bee secretion that is used in the nutrition of larvae, as well as adult queens" (Wikipedia), come into play. As can be seen from in figure 1, 7 months supplementation with 5% Royal Jelly produced profound effects on the expression of the rats' pituitary hormone genes, one of which (you will have guessed that) is POMC.
|Figure 1: Expression of Pituitary Hormone Genes in Middle-Aged Female Rats Fed a 5% Royal Jelly Diet for 7 Months. (Narita. 2009)|
Yet, before you break into the next beeyard, you should consider that...
- the amount of royal jelly the rats consumed in the study, i.e. 5% of their daily food intake is almost impossible to achieve without plundering beeyards all over the country (for the same reason it is no practical alternative to medications for "rejuvinating the pituitary" which the author of the ergo-log post seems to imply in the headline of his post)
- an upregulation in gene expression alone does not guarantee an increase in metabolic rate (the increase in the thyroid (pre-)hormone T4, for example, was non-significant, despite a significant increase in TSH related gene expression)