Biochemistry of Alcohol Metabolism

BIOCHEMISTRY OF ALCOHOL METABOLISM

Alcohol is a psychoactive medication/drink. It is the second most utilized psychoactive medication. (Caffeine is appraised as the first most utilized.) It is viewed as a depressant in light of the fact that at medium to high focuses, it depresses neural firing (Despite the fact that at low levels, it can have the inverse impact) Due to its small and amphiphilic nature, ethanol is soluble in water and fat, so it is able to cross cell membranes, giving it great access to do harm to cells and affecting the entire body [1].

Figure: Ethanol molecule [3]

[pic 1][pic 2]

Alcohol is consumed from the stomach and small digestive system by diffusion. Most retention happens from the small digestive tract because of its large surface area and rich blood supply. The rate of absorption shifts with the emptying time of the stomach. By and large, the higher the alcohol concentration of the drink, the quicker the rate of absorption. Alcohol is wiped out from the body by excretion and metabolism. Most alcohol is metabolized, or burned, in a way like nourishment, yielding carbon dioxide and water. A little parcel of liquor is discharged, for example, through the breath, leaving the body as liquor, unaltered. It is this last process that takes into consideration breath liquor testing [2].

Not at all like food which oblige digestion before they can be absorbed, the little ethanol particles can diffuse directly through the dividers of a vacant stomach to achieve the brain in a matter of seconds. Ethanol is a poison and too high a dose of it triggers one of the body's essential resistances against toxic substance, in particular vomiting. Commonly, liquor is taken progressively and in a dilute form and in this way the vomiting reflex is postponed and the liquor is absorbed [2].

Liquor is metabolized for the most part in the liver in two stages and catalyzed by liquor and aldehyde dehydrogenases, with NAD+ as a hydrogen acceptor. As can be seen from the pathway indicated in Figure 2, the presence of liquor inside the cell makes a heavy demand on a restricted supply of NAD+, (a niacin-determined coenzyme) and hence the NAD+/NADH proportion falls. Different responses that rely on upon NAD+ will along these lines be diminished [3].

Figure 2: Metabolism of alcohol in the liver [3]

Ethanol[pic 3]

                        NAD+[pic 4][pic 5]

                NADH + H+

                                        [pic 6]

                                        Acetaldehyde[pic 7]

                        [pic 8][pic 9]

                        NAD+[pic 10]

[pic 11]

                NADH + H+

[pic 12]

Acetic Acid

ALCOHOL IN BRAIN

Brain cells are particularly sensitive to excessive exposure to alcohol. The brain shrinks even in persons who drink moderately. The degree of shrinkage is corresponding to the amount consumed. Abstinence together with great nourishment can reverse a portion of the brain harm. Be that as it may, delayed drinking past a singular's ability can bring about extreme and irreversible harm to vision, memory and learning capacity. Liquor expands urine yield. This is on account of liquor depresses the pituitary organ's production of the antidiuretic hormone vasopressin [4].

Long Term Effects of Alcohol

• Diabetes (non-insulin dependent)
• Ulcers of the stomach and intestines
• Severe psychological depression
• Impaired immune response
• Central nervous system damage
• Malnutrition
• Bone deterioration and osteoporosis.

BIOCHEMISTRY OF NITCOTINE

“Smoking is relaxing”, even though it is a poison, a paralytic, and a stimulant [5]. This because the smoker lights a cigarette, breathes in profoundly, and at that point breathes out, long and moderate. Inside seven seconds, the full breath of the inward breath has expanded the stream of blood and oxygen to the heart, and the body relaxes. Not as a result of the cigarette, however because of the long moderate inward breath and exhalation [5].

Within moments of the initial inhalation, nicotine is empowering pleasure focuses in the brain – the same focuses focused by cocaine. That is the reason we call nicotine a drug. Seven to after fifteen minutes, the nicotine enters the liver after its brisk frenzy through the lungs. Cilia are hair-like developments that respond to inhaled toxic substances by "clearing" or coughing the offenders pull out of the airways. On the off chance that the smoker puffs sufficiently long, the cilia get to be paralyzed, and can no more secure the lungs and at last the blood from this infringing threat [6]. With time, the lungs and liver lose their ability to work as the vital filtering systems of the body.

Nicotine biochemically alerts the liver to discharge sugar into the circulatory system. The raised glucose brings a physical elevate. So now smokers have a feeling of relaxation and elevate. High sugar levels in the blood call the pancreas into action. The pancreas discharges insulin to cut down the overabundance glucose. Diving glucose brings on emotions of weakness, fractiousness, craving, or a yearning for something, anything to help glucose, as – Surprise! Another cigarette! On the other hand sugar, treat, chocolate, alcohol, - all prominent and all addictive [6].