Wine and polyphenols
Wine is an alcoholic beverage obtained from the bacterial fermentation of grapes harvested from vitis vinifera ; it can be white, rosé or red, depending on the type of grape and the vinification technique, which together determine the quality and quantity of the phenolic pigments.
If the maceration of the must is used, the quantity of polyphenols in the wine depends on the initial concentration in the peel of the grape used and is directly proportional to the time of maceration of the must .
From the organoleptic and gustatory point of view, the polyphenols are the color, aroma and stability of the wine. From a biochemical and metabolic point of view, instead, wine polyphenols perform three very important functions:
- Antioxidant
- anticancer
- antiatherogenic
The following article will discuss the interaction or influence of polyphenols on cholesterol transport and metabolism.
What is cholesterol?
Cholesterol is a steroid with a polycyclic structure (Ciclopentanoperidrofenantrene); it is white in color and has a waxy consistency. Cholesterol is INDISPENSABLE to animal life, while plants contain other similar substances called phytosterols.
The human organism autonomously synthesizes about 70% of the cholesterol necessary for survival and completes its needs by feeding on foods of animal origin; if the exogenous cholesterol intake is excessive, if genetic alterations are present or even the combination of both, the levels of total cholesterol (or partial LDL) could increase and be excessive.
Lipoproteins
How does cholesterol move inside the body?
Cholesterol is a fundamental molecule both to the formation of cellular membranes and to steroid hormone production, therefore, its continuous tissue availability is of vital importance. On a plasmatic level, cholesterol is bound by special transporters that determine its destination (towards the peripheries or towards the liver); these carriers are called LIPO-PROTEIN and the organism synthesizes different types based on the specific function:
- KILOMYCHRONES: they are lipoproteins produced by the intestine and transport the lipids absorbed in the intestine from the lymphatic circulation to the bloodstream
- VLDL: very low intensity lipoprotein; they are produced by the liver and are responsible for the transport of triglycerides and cholesterol from the liver to the tissues
- IDL: intermediate density lipoprotein; derive from VLDL that lose the lipid portion of triglycerides. They are responsible for transporting the remaining lipids to the tissues
- LDL: low density lipoprotein; derive from IDLs that lose a further lipid portion of triglycerides and are mainly responsible for the transport of cholesterol to tissues
- HDL: high density lipoprotein; they are produced by the liver and intestines and are responsible for the transport of cholesterol from the tissues to the liver.
In addition to the total cholesterol levels, also the alteration of the ratio between LDL / HDL and the level of oxidation of the LDL, contribute to the increase of the lipid deposit in the arteries. This phenomenon, linked to a state of chronic inflammation and possibly to high levels of homocysteinemia, is directly related to the increase in cardiovascular risk for ATEROSCLEROSIS.
The best values for the most significant blood lipoproteins are:
| Total cholesterol | <200mg / dl |
| LDL | <130mg / dl |
| HDL | > 40 mg / dl in men> 50mg / dl in women |
What is atherosclerosis?
Atherosclerosis is a multifactorial degenerative disease that affects the middle and large caliber arteries. In Italy and in many other countries of the world it represents a major health problem, mostly linked to the typical lifestyle of industrialized societies. Atherosclerosis is in fact the cause of very serious pathologies such as angina pectoris, heart attack and stroke ... www.my-personaltrainer.it/salute/aterosclerosi.html
Polyphenols and cardiovascular risk
Phenolic substances are molecules that can prevent various degenerative processes in the body, including atherosclerosis. Polyphenols are contained in many plant-based foods such as fruit, vegetables, extra virgin olive oil, green tea and wine.
The wine mainly contains tannins, flavonoids and resveratrol in its TRANS form, hence the trans-resveratrol. This powerful antioxidant appears to significantly increase the fluidity of blood by improving the circulation and reducing cardiac fatigue; in addition, trans-resveratrol has a fairly good systemic anti-inflammatory function (by reduction of cyclooxygenase-2 [COX-2]) and significantly lowers the level of platelet aggregation (due to the inhibition of eicosanoid synthesis). Both of these characteristics lead to a reduction in the onset of atherosclerosis and cardiovascular risk.
Benefits
Trans-resveratrol is extremely effective in the fight against LDL lipoprotein oxidation. The oxidized LDLs are considerably smaller and less sensitive to the uptake of receptors than those that are NOT oxidized, therefore, their permanence in the blood significantly increases; this dilation of the metabolic times of the oxidized lipoproteins favors the possibility that these penetrate into the arterial coats and give rise to the process of atherogenesis.
The antioxidant and preventive function of trans-resveratrol depends on its ability to penetrate LDL and chelate copper (Cu2 +) as the main catalyst of oxidative processes that compromise the structural-functional integrity of lipids contained in lipoprotein. The anti-oxidant mechanism of trans-resveratrol interrupts the ATEX oxidative cascade of the reaction preventing the cytotoxicity of oxidized and potentially atherogenic LDL.
NB. The ethyl alcohol contained in the wine, if introduced in excess, causes a rise in the blood triglycerides which can favor the increase of the cardiovascular risk.
In conclusion, wine containing phenolic substances can be considered a very useful drink when reaching the level of food antioxidants; however, considering that it is an alcoholic product, it is not totally correct to recommend frequent and systematic consumption. On the other hand, in the absence of pathologies and IF IT WAS, the consumption of 2-3 alcoholic units per day of red wine can favor the prevention of lipid oxidation and cholesterol (LDL), consequently also reducing the cardiovascular risk.
