Monacolins are substances produced by the fermentation of red rice, useful in the control of cholesterol and in the prevention of degenerative diseases. Let’s find out better.
Where is monacolin found
Monacolin was discovered in 1979. Endo studied the fermentation of the yeast Monascus purpureus and found that a metabolite produced in the fermentation process had strong inhibitory capabilities of the enzyme HMG-CoA-reductase (3-hydroxy-3-methyl-glutaryl-CoenzymeA-reductase), one of the key enzymes involved. in the hepatic synthesis of cholesterol. That metabolite was monacolin K.
The fermentation of Monascus purpureus has been known in Chinese nutrition and herbal medicine for centuries. In the food sector, yeast is added to rice (Oryza sativa) to allow fermentation and the product obtained is used for the preparation of various dishes.
Traditional Chinese medicine, on the other hand, uses fermented red rice to improve blood circulation, in case of indigestion and dysentery.
Properties of monacolin
Monacolins and, in particular, monacolin K, play an important role in controlling cholesterol levels; in particular they intervene in the hepatic metabolism of cholesterol and inhibit HMG-CoA-reductase, an enzyme intermediate in the biosynthetic process.
Monacolins compete structurally with 3-hydroxy-3-methyl-CoA-reductase for the active site (point where the chemical reaction takes place) of the enzyme HMG-CoA-reductase. In this way they block the metabolic pathway which, passing through intermediates such as mevalonate and squalene, leads to the synthesis of cholesterol in the liver. In this way the endogenous production is reduced.
Numerous clinical studies conducted on fermented red rice have highlighted the significant reduction in cholesterolemia, in particular LDL cholesterol, with increases instead of HDL.
The effectiveness of these extracts are, therefore, beyond doubt; so much so that unlike other active ingredients, companies can report on the labels of their fermented red rice products references to the effects favoring the maintenance of normal cholesterol levels in the blood, always with the integration of a varied diet aimed at the same purpose; obviously, the same labels cannot indicate references to pathological forms for which a medical prescription is required.
This indication on the label may be reported, in accordance with European legislation, only for daily intake of 10 mg of monacolin. The dosages on the market vary from a minimum of 5mg to a maximum of 80mg, while food supplements cannot exceed 3mg.
Also, on the market there are often products enriched with antioxidants to improve circulation, such as Coenzyme Q10. By inhibiting HMG-CoA-reductase, the synthesis of this important coenzyme is also blocked. CoA enters into many fundamental metabolic reactions, such as the fatty acid cycle and cellular respiration, activating enzymes and allowing them to act.
Fermented red rice is also proving useful for the prevention of degenerative diseases (Alzhaimer); osteoporosis and tumors, thanks to the presence in the extract of other biologically active substances, such as β-sitosterol, campesterol, stigma sterol, sapogenins, isoflavones and monounsaturated fatty acids.
While the fact that they have a similar structure to statins may suggest that monacolins have the same side effects, numerous studies have shown that this is not the case.
Statins have various contraindications, especially to the detriment of muscle tissue, as they induce rhabdiomyolysis. Rhabdomyolysis is characterized by necrosis of striated muscle fibrocells and consequent release of their contents into the bloodstream, including enzymes (creatine kinase, aldolase, glutamic-oxaloacetic transaminase), hemoproteins (myoglobin), electrolytes (potassium, phosphates).
A recent study has shown that fermented red rice, administered at dosages even double those allowed (1800mg / day titrated in 6mg of monacolins), is well tolerated even by patients at risk of toxicity; the incidence of myalgia coincides with placebo in a small series, but the lowering of LDL cholesterol is more important than placebo.
Monacolins are contraindicated in pregnancy and breastfeeding and for those already on statin therapy, obviously because a sum of the actions could accentuate the undesirable effects. In addition to statins, the association with any other drug or substance with a lipid-lowering action is contraindicated.