Vitamin B3/en: Difference between revisions

Line 30:

[[File:Pellagra2.jpg|thumb|A man with [[pellagra]], which is caused by a chronic lack of vitamin B3 in the diet]]

Severe vitamin B3 deficiency in the diet causes the disease [[pellagra]], characterized by [[diarrhea]], sun-sensitive [[dermatitis]] involving hyperpigmentation and thickening of the skin (see image), inflammation of the mouth and tongue, delirium, dementia, and if left untreated, death.> Common psychiatric symptoms include irritability, poor concentration, anxiety, fatigue, loss of memory, restlessness, apathy, and depression. The biochemical mechanisms for the observed deficiency-caused neurodegeneration are not well understood, but may rest on A) the requirement for [[nicotinamide adenine dinucleotide]] (NAD+) to suppress the creation of neurotoxic tryptophan metabolites; B) inhibition of mitochondrial ATP generation resulting in cell damage; C) activation of the [[poly (ADP-ribose) polymerase]] (PARP) pathway, as PARP is a nuclear enzyme involved in DNA repair, but in the absence of NAD+ can lead to cell death; D) reduced synthesis of neuro-protective [[brain-derived neurotrophic factor]] or its receptor [[tropomyosin receptor kinase B]]; or, E) changes to [[Gene expression|genome expression]] directly due to the niacin deficiency.

Severe vitamin B3 deficiency in the diet causes the disease [[pellagra]], characterized by [[diarrhea]], sun-sensitive [[dermatitis]] involving hyperpigmentation and thickening of the skin (see image), inflammation of the mouth and tongue, delirium, dementia, and if left untreated, death. Common psychiatric symptoms include irritability, poor concentration, anxiety, fatigue, loss of memory, restlessness, apathy, and depression. The biochemical mechanisms for the observed deficiency-caused neurodegeneration are not well understood, but may rest on A) the requirement for [[nicotinamide adenine dinucleotide]] (NAD+) to suppress the creation of neurotoxic tryptophan metabolites; B) inhibition of mitochondrial ATP generation resulting in cell damage; C) activation of the [[poly (ADP-ribose) polymerase]] (PARP) pathway, as PARP is a nuclear enzyme involved in DNA repair, but in the absence of NAD+ can lead to cell death; D) reduced synthesis of neuro-protective [[brain-derived neurotrophic factor]] or its receptor [[tropomyosin receptor kinase B]]; or, E) changes to [[Gene expression|genome expression]] directly due to the niacin deficiency.

Niacin deficiency is rarely seen in developed countries, and it is more typically associated with poverty, malnutrition or malnutrition secondary to chronic [[alcoholism]]. It also tends to occur in areas where people eat [[maize]] (corn) as a staple food, as maize is low in digestible niacin. A cooking technique called [[nixtamalization]], that is, pretreating with alkali ingredients, increases the [[bioavailability]] of niacin during maize meal or flour production. For this reason, people who consume corn as tortillas or [[hominy]] are at less risk of niacin deficiency.

@@ Line 30: / Line 30: @@
 [[File:Pellagra2.jpg|thumb|A man with [[pellagra]], which is caused by a chronic lack of vitamin B<sub>3</sub> in the diet]]
-Severe vitamin B<sub>3</sub> deficiency in the diet causes the disease [[pellagra]], characterized by [[diarrhea]], sun-sensitive [[dermatitis]] involving hyperpigmentation and thickening of the skin (see image), inflammation of the mouth and tongue, delirium, dementia, and if left untreated, death.> Common psychiatric symptoms include irritability, poor concentration, anxiety, fatigue, loss of memory, restlessness, apathy, and depression. The biochemical mechanisms for the observed deficiency-caused neurodegeneration are not well understood, but may rest on A) the requirement for [[nicotinamide adenine dinucleotide]] (NAD+) to suppress the creation of neurotoxic tryptophan metabolites; B) inhibition of mitochondrial ATP generation resulting in cell damage; C) activation of the [[poly (ADP-ribose) polymerase]] (PARP) pathway, as PARP is a nuclear enzyme involved in DNA repair, but in the absence of NAD+ can lead to cell death; D) reduced synthesis of neuro-protective [[brain-derived neurotrophic factor]] or its receptor [[tropomyosin receptor kinase B]]; or, E) changes to [[Gene expression|genome expression]] directly due to the niacin deficiency.
+Severe vitamin B<sub>3</sub> deficiency in the diet causes the disease [[pellagra]], characterized by [[diarrhea]], sun-sensitive [[dermatitis]] involving hyperpigmentation and thickening of the skin (see image), inflammation of the mouth and tongue, delirium, dementia, and if left untreated, death. Common psychiatric symptoms include irritability, poor concentration, anxiety, fatigue, loss of memory, restlessness, apathy, and depression. The biochemical mechanisms for the observed deficiency-caused neurodegeneration are not well understood, but may rest on A) the requirement for [[nicotinamide adenine dinucleotide]] (NAD+) to suppress the creation of neurotoxic tryptophan metabolites; B) inhibition of mitochondrial ATP generation resulting in cell damage; C) activation of the [[poly (ADP-ribose) polymerase]] (PARP) pathway, as PARP is a nuclear enzyme involved in DNA repair, but in the absence of NAD+ can lead to cell death; D) reduced synthesis of neuro-protective [[brain-derived neurotrophic factor]] or its receptor [[tropomyosin receptor kinase B]]; or, E) changes to [[Gene expression|genome expression]] directly due to the niacin deficiency.
 Niacin deficiency is rarely seen in developed countries, and it is more typically associated with poverty, malnutrition or malnutrition secondary to chronic [[alcoholism]]. It also tends to occur in areas where people eat [[maize]] (corn) as a staple food, as maize is low in digestible niacin. A cooking technique called [[nixtamalization]], that is, pretreating with alkali ingredients, increases the [[bioavailability]] of niacin during maize meal or flour production. For this reason, people who consume corn as tortillas or [[hominy]] are at less risk of niacin deficiency.