Terms in this set (31)
aromatic ring with a nitrogen and a carboxylic acid group 2 carbons away from the nitrogen
nicotinic acid amide(synonym)
aromatic ring with a nitrogen and a amidegroup 2 carbons away from the nitrogen
niacin bound to small peptides
niacin bound to complex carbohydrates
oxidized form Niacin
reduced form Niacin
Southeast US got this disease because corn not treated with lime water and only 10% of niacin available in corn.
also people in US ate pork fat low in tryptophan
Discovery of pellagra
said that pellagra was not infectious because doctors and nurses didn't get the disease when treating infected. Took pills of feces and urine. Died at the height of pellagra epidemic (not form pellagra). Wasn't able to find out that he was correct.
Joseph Goldberger story
enrichment of grains with niacin
Why did pellagra epidemic end?
symptoms of pellagra
NAD (Nicotinamide adenine dinucleotide)
NADP (Nicotinamide adenine dinucleotide phosphate)
coenzyme form of Niacin
Tryptophan to Niacin occurs in?
60mg tryptophan: 1mg niacin
amount of tryptophan to produce niacin
Riboflavin, B6, iron
other nutrient interactions during Tryptophan's conversion to NAD?
catalyst of nicotinic acid adenine dinucleotide to nicotinamide adenine dinucleotide?
catalyst of nicotinamide adenine dinucleotide to nicotinamide adenine dinucleotide phosphate?
catalyst NAD => Nicotinamide
catalyst of NADP phosphate removal
In small intestine
Normal concentration: sodium dependent carrier by facilitated diffusion.
High concentration: passive diffusion
Absorption in GI tract
kidney tubules and red blood cells
where are carrier proteins needed for Niacin to enter cells?
nicotinamide free form
nicotinic acid bound to proteins
Transportation in blood?
all tissue. traps NAD/NADP in cells
which tissues can form nicotinamide/ nicotinic acid into the coenzyme form
transfer electrons and hydrogens as a coenzyme for dehydrogrenase enzymes
role of NAD
Thiamin/ Riboflavin interaction
NADPH generated in Pentose Phosphate Pathway and is a reducing agent for biosynthetic pathways
1) ADP-ribose donation
2) postranslation modification of histones
3) formation of cyclic ADP-ribose
4) transfer of mono ADP-ribose to proteins on cell for immune response
5) release of calcium in neurons
Non-redox role of niacin
N'methyl nicotinamide (NMN)
N'methyl 2-pyridone 5-carboxamide
N'methyl 4-pyridone carboxamide
N'methyl nictonic acid
low excretion can mean deficient
excretion of niacin
RDA 16 mg/day =men
14 mg/day = women
NE = 60mg Tryptophan
UL = 35 mg/day
Niacin RDA/AI? UL?
What is an NE
Nicotinic acid flushing indicative of liver damage
Basis of Niacin UL
6g/day used to treat hypercholesterolemia
lower: cholesterol, triglycerides, LDL
drug use of Niacin