维生素B3

維生素B3屬於維生素B族,包括三個維生素異構體英語vitamer,分別是煙酸煙醯胺煙醯胺核糖[1]這三種維生素異構體在人體內都會轉化成煙醯胺腺嘌呤二核苷酸(NAD)。[1]生命需要NAD,而人體不能在沒有維生素B3色氨酸的情況下合成NAD。[1]煙醯胺核糖於2004年被確認是維生素B3之一。[2][1]

維生素B3
藥物種類
維生素B3的三個維生素異構體之一——煙醯胺的結構
生物靶標酶輔因子
ATC代碼A11H
外部連結
MeSHD009536
AHFS/Drugs.comNiacin

動植物可以通過色氨酸合成煙酸。[3]煙酸存在於許多食物中,其中肉類、家禽、金槍魚三文魚中的煙酸含量最高,而堅果、豆類和種子中的煙酸含量較少。[4][5]作為營養補充品的煙酸可以治療因缺乏維生素B3導致的糙皮病。糙皮病的症狀有皮膚和口腔病變、貧血、頭痛和疲倦。[6]許多國家都會要求在麵粉和其它糧食添加煙酸防止糙皮病。[4][7]

煙醯胺輔因子煙醯胺腺嘌呤二核苷酸(NAD)和煙醯胺腺嘌呤二核苷酸磷酸(NADP+)的組成部分。雖然煙酸和煙醯胺在維生素活性上相同,但作為醯胺的煙醯胺不會還原膽固醇,也不會造成臉紅英語flushing (physiology)[8][9]由於臉紅被認為是不良反應,因此煙醯胺被推薦為維生素B3缺乏症的治療方法。[10]

參考資料

  1. ^ 1.0 1.1 1.2 1.3 Stipanuk, Martha H.; Caudill, Marie A. Biochemical, Physiological, and Molecular Aspects of Human Nutrition - E-Book. Elsevier Health Sciences. 2013: 541. ISBN 9780323266956 (英語). Vitamin B3... potentially includes three different molecular forms: nicotinic acid, niacinamide, and nicotinamide riboside 
  2. ^ Bieganowski, P; Brenner, C. Discoveries of nicotinamide riboside as a nutrient and conserved NRK genes establish a Preiss-Handler independent route to NAD+ in fungi and humans.. Cell. 14 May 2004, 117 (4): 495–502. PMID 15137942. doi:10.1016/s0092-8674(04)00416-7 . 
  3. ^ Institute of Medicine. Niacin. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. 1998: 123–149 [29 August 2018]. ISBN 9780309065542. (原始內容存檔於2018-09-01). 
  4. ^ 4.0 4.1 Niacin. Micronutrient Information Center, Linus Pauling Institute, Oregon State University, Corvallis, OR. 8 October 2018 [16 September 2019]. (原始內容存檔於2019-09-12). 
  5. ^ Niacin Fact Sheet for Health Professionals. Office of Dietary Supplements, US National Institutes of Health. 3 June 2020 [29 June 2020]. (原始內容存檔於2020-06-23). 
  6. ^ Hegyi J, Schwartz RA, Hegyi V. Pellagra: dermatitis, dementia, and diarrhea. International Journal of Dermatology. January 2004, 43 (1): 1–5. PMID 14693013. S2CID 33877664. doi:10.1111/j.1365-4632.2004.01959.x. 
  7. ^ Why fortify?. Food Fortification Initiative. 2017 [4 April 2017]. (原始內容存檔於4 April 2017). 
  8. ^ Jaconello P. Niacin versus niacinamide. CMAJ. October 1992, 147 (7): 990. PMC 1336277 . PMID 1393911. 
  9. ^ Kirkland JB. Niacin requirements for genomic stability. Mutation Research. May 2012, 733 (1–2): 14–20 [2023-01-29]. PMID 22138132. doi:10.1016/j.mrfmmm.2011.11.008. (原始內容存檔於2020-08-04). 
  10. ^ World Health Organization. Pellagra And Its Prevention And Control In Major Emergencies (報告). World Health Organization (WHO). 2000. hdl:10665/66704 . WHO/NHD/00.10.