Ergosterol
(Redirected from Provitamin D2)
Ergosterol: The Fungal Sterol with Multifaceted Implications
Ergosterol (ergosta-5,7,22-trien-3β-ol) is a pivotal sterol abundantly found in fungi. Analogous to cholesterol in animal cells, ergosterol's centrality to fungal cellular architecture renders it a critical target for therapeutic agents. Notably, ergosterol metamorphoses into vitamin D2 upon ultraviolet (UV) light exposure, adding another dimension to its significance.
Overview[edit | edit source]
A quintessential component of fungal cell membranes, ergosterol mirrors the functionality of cholesterol in the animal cellular milieu. It is indispensable for fungal cell membrane integrity, fluidity, and potential drug interactions.[1]
Role in Fungi[edit | edit source]
Ergosterol traces its origins to its extraction from the fungal genus Claviceps, commonly dubbed as ergot. Pervading a vast fungal spectrum, this sterol establishes itself as the building block of cell membranes in fungi like yeasts, offering a counterpart to cholesterol's role in animals.
Target for Antifungal Drugs[edit | edit source]
Ergosterol's exclusive presence in fungal membranes (and its absence in mammalian counterparts) earmarks it as an ideal target for antifungal therapeutics. Its trace presence in certain protists, such as trypanosomes, has facilitated the repurposing of some antifungals against ailments like West African sleeping sickness.[2]
Amphotericin B is an archetypal antifungal agent that avidly interacts with ergosterol. This liaison culminates in the formation of membrane pores, initiating the efflux of crucial ions and compounds, ushering the fungal cell towards demise. Even as modern medicine paves the way for less toxic alternatives, Amphotericin B remains a bulwark against severe fungal and protozoan infections, albeit with potential side effects.[3]
Compounds like miconazole, itraconazole, and clotrimazole deter ergosterol synthesis from its precursor, lanosterol. The enzymatic transition from lanosterol to ergosterol, which involves farnesyl pyrophosphate assembly and subsequent demethylation, is specifically obstructed by these "azole" antifungals.[4]
As a Vitamin D2 Precursor[edit | edit source]
Ergosterol's photochemical transformation, instigated by ultraviolet exposure, generates ergocalciferol, or vitamin D2. The food industry capitalizes on this by irradiating mushrooms to elevate their vitamin D content. Large-scale fungal cultivation further allows ergosterol extraction and subsequent chemical conversion to vitamin D, finding utility as dietary supplements and food fortifiers.
In a historical vignette, ergosterol-derived vitamin D mixtures were marketed as Viosterol in the 1930s.[5]
Toxicity[edit | edit source]
Ergosterol, in its powdered avatar, can be a potent irritant, impacting skin, ocular, and respiratory tissues. Ingesting significant amounts may precipitate hypercalcemia, characterized by surging blood calcium levels. Chronic hypercalcemia could pave the way for calcium salt deposition in soft tissues, imperiling organs like kidneys.[6]
See Also[edit | edit source]
- Mushrooms and vitamin D
- Biochemistry of ergosterol synthesis
References[edit | edit source]
- ↑ Rawlings, B. J. "Triterpenoids." Natural Product Reports, vol. 15, no. 3, 1998, pp. 221-239.
- ↑ Mäser, Pascal, et al. "Drug resistance in African trypanosomiasis: the melarsoprol and pentamidine story." Trends in parasitology, vol. 19, no. 2, 2003, pp. 81-88.
- ↑ Gray, Kevin C., et al. "Amphotericin primarily kills yeast by simply binding ergosterol." Proceedings of the National Academy of Sciences, vol. 109, no. 7, 2012, pp. 2234-2239.
- ↑ Monk, Brian C., et al. "The target of azole antifungal drugs in Saccharomyces cerevisiae is 14α-demethylase (encoded by the ERG11 gene)." Antimicrobial agents and chemotherapy, vol. 45, no. 3, 2001, pp. 987-993.
- ↑ Norman, Anthony W. "From vitamin D to hormone D: fundamentals of the vitamin D endocrine system essential for good health." The American journal of clinical nutrition, vol. 88, no. 2, 2008, pp. 491S-499S.
- ↑ Kaufman, David W., et al. "Hypercalcemia and elevated serum vitamin D concentrations in black Americans." The American journal of clinical nutrition, vol. 37, no. 5, 1983, pp. 805-807.
| Ergosterol Resources | |
|---|---|
|
 |
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
|
WikiMD's Wellness Encyclopedia |
| Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD
