Apigenin also offers anti-inflammatory effects. One way that it does this is by inhibiting an enzyme called COX-2 that converts arachidonic acid, a fatty acid, into eicosanoids that are the direct cause of some types of pain and inflammation. Most commerical analgesics, such as aspirin and non-steroidal anti-inflammatory drugs work through the same mechanism,although apigenin doesn't produce the side effects of these drugs, including ulcers, cardiovascular disease, and possible kidney failure with long-term, high dose, usage. Since cancer has an inflammatory component, it's not surprising that apigenin has been shown in several studies, mostly involving animals, to prevent several types of cancer. These include cancers of the lungs, ovaries,prostate, thyroid, and pancreas. Apigenin also blocks the activity of the HER-2 gene, which promotes breast cancer in many women. Emerging studies show that apigenin can forestall the spread of malignant melanoma, the most fatal type of skin cancer, by both promoting the suicide (apoptosis) of cancer cells, and also through inhibiting the development of new blood vessels (angiogenesis) that tumor cells require to spread throughout the body, or metastasize.Many cancers start as a result of oxidative damage to cellular DNA, an effect also blocked by apigenin. If that wasn't enough, apigenin increases the activity of the P53 tumor suppressor protein that destroys tumors in the body. Some studies show that when provided as an adjunctive to chemotherapy, apigenin improves the ability of chemo agents to destroy cancer cells. Prostate cancer is promoted by insulinlike growth factor-1 (IGF-1), but apigenin blocks this stimulation by increasing the production of the primary protein binder of IGF-1, which renders it harmless. If you suffer from allergies or asthma, you'll like the fact that apigenin lowers levels of an immune cell called immunoglobulin-E that plays a central role in the onset of both allergies and asthma.
Bodybuilders would find apigenin useful because it's a natural aromatase inhibitor. Aromatase is the enzyme that converts androgens, including testosterone, into estrogen. But the most interesting aspect of apigenin in relation to testosterone is shown in an upcoming study. Testosterone levels drop in most men beginning at about age 40. While there are various theories as to the cause of this hormonal decline, one plausible theory relates the drop in testosterone to a decrease of a protein synthesized in the testes, and wherever else steroid hormones are made in the body, including the brain and adrenal glands. This protein is called the steroidogenic acute regulatory protein or StAR. What StAR does is transport cholesterol, which is the raw material from which all steroid hormones are produced from, including testosterone, estrogen, and cortisol, from the outer mitochondrial membrane in cells to the inner membrane, where production of the hormones begins. Cholesterol requires the StAR transport protein because it cannot penetrate the inner mitochondrial cell membrane by itself; it must be ferried or transported into the cell. The production of StAR is stimulated by lutenizing hormone (LH) secreted from the anterior pituitary gland. StAR is considered the rate-limiting step in steroid hormone synthesis, since without the raw material provided by cholesterol, no hormones can be made.
The synthesis of StAR is known to decline with age,and many scientists think this may be the root cause of the age-related lowering of testosterone levels. Alcohol also blocks the activity of StAR, which explains why drinking too much booze can lower testosterone levels in men. In the new study, isolated mouse cells from the Leydig cells of the testes, where testosterone is primarily synthesized, were incubated with apigenin. Doing this increased the activity of cyclic AMP, which kick starts steroid synthesis, as well as StAR. Apparently, apigenin can boost the gene expression of StAR. Too much COX-2 is also thought to play a role in declining testosterone levels, and apigenin blocked this effect, too. In so doing, apigenin inhibited the activity of another protein (DAX-1) that interferes with StAR activity in the testes. When this protein is blocked, the sensitivity of the testes cells to StAR increases dramatically, which in turn significantly increases the production of testosterone. What this means in simple terms, is that apigenin may provide a natural antidote to the problem of decreased testosterone production as a result of aging. What remains to be seen is whether this process works as well in intact human Leydig cells as it does in isolated mouse cells exposed to large amounts of apigenin. But considering that apigenin also blocks aromatase, I would suspect that apigenin shows good potential to be a useful antiaging supplement.
Lia, W, et al. Effects of apigenin on steroidogenesis and steroidogenic acute regulatory gene expression in mouse Leydig cells.J Nutr Biochem 2010;In press.
©,2015 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited
