What is the problem 2 - About nicotinamide (NAD) in detail

Vitamin B3 has several names: Nicotinic acid and niacin. Nicotinamide or niacinamide is the active form of niacin in the body. The liver produces this water-soluble vitamin from the amino acid tryptophan. However, bacteria in the beneficial intestinal flora can also produce niacin from tryptophan.

About nicotinamide in detail and the role of tryptophan

Foods of plant origin contain nicotinic acid. Foods of animal origin contain nicotinamide (niacinamide).

Nicotinic acid is essential for the synthesis of sex hormones (oestrogen, progesterone, testosterone), cortisone, thyroxine and insulin. It is necessary for the healthy functioning of the brain and the peripheral nervous system.

In animals and humans, nicotinic acid is converted into nicotinamide in the liver. Cytochrome p450 enzymes transport functional groups of various substrates (hydroxylation, carboxylation, decarboxylation, desaturation and amidation).

The amidation of nicotinic acid to nicotinamide generally takes place in the Liver. The biocatalyser of this process is the cytochrome p450 enzyme system.

Niacinamide is a component of the nicotinamide adenine dinucleotide (NAD+).

NAD+ is required by more than 100 enzymes involved in the metabolism of carbohydrates, fats, proteins and alcohol, DNA repair and cell signalling. Tissues that consist of rapidly multiplying cells (skin, intestinal epithelial cells, brain) have a high energy requirement and rapid biochemical processes. These tissues are most affected by pellagra.
Nicotinamide adenine dinucleotide (NAD+) is an essential cofactor found in all living cells. It plays an important role in electron transport through the mitochondrial membranes. The function of the electron transport chain leads to the transfer of hydrogen through the membrane. This process creates a hydrogen gradient that triggers the oxidative phosphorylation of ADP, the synthesis of ATP.
NAD+ therefore plays a decisive role in energy production in the mitochondria and in many enzymatic redox reactions. Numerous biochemical processes in the body require NAD+: cholesterol metabolism, neurotransmitter metabolism, production of free radicals and detoxification. Disruptions in NAD+ production are the cause of numerous diseases, including metabolic disorders, neurodegenerative diseases and a lack of cellular defence mechanisms against oxidative stress.

The mitochondrial disease

Animal studies have shown that the tryptophan-nicotinamide conversion pathway (kynurenine pathway) influences homeostasis, the internal stability of the organism and the ability to adapt to a changing environment.
The correct functioning of the kynurenine pathway is a prerequisite for health. The occurrence of diseases, the utilisation of nutrients and hormones as well as the function of the immune system all depend on the Kynureninweg from. Studies on humans have shown that infants form 1 mg of nicotinamide from 67 mg of ingested tryptophan. The conversion rate of tryptophan to nicotinamide increases from the middle to the end of pregnancy (Tsutomu Fukuwatari and Katsumi Shibata 2013). The conversion of tryptophan into nicotinic acid nicotinamide is essential for supplying the body with niacin.
In the liver, the mitochondria are specialised in the detoxification of ammonia. The urea cycle takes place partly in the mitochondria of the liver. The final step of catabolism, terminal oxidation, also takes place in other mitochondria, where the hydrogen bound to cofactors is oxidised to water. Nearly 95 % of the energy released during biological oxidation is terminal oxidation. The body needs mitochondria for cholesterol metabolism, the Oestrogen- and testosterone synthesis, neurotransmitter metabolism and the production and detoxification of free radicals.