Oyster mushroom

• How It Works

  Oyster mushroom has not been shown to treat cancer in humans.

  Oyster mushroom is an edible fungus. It is used in traditional medicine to treat infections, diabetes, cancer, and to lower cholesterol. Laboratory experiments and studies done in mice have shown that oyster mushrooms have antitumor, antifungal, and cholesterol-lowering properties. A study done in children with upper respiratory tract infections showed that oyster mushroom has anti-allergic effects. It was also shown to lower glucose levels and increase insulin levels in patients with type 2 diabetes, but more studies are needed to confirm such effects.

• Purported Uses
  • Antitumor
    Oyster mushrooms increased survival in tumor-bearing mice but no such studies have been done in humans.
  • Antifungal
    One laboratory study showed that oyster mushroom has antifungal activity.
  • High fat levels in the blood
    Studies done in mice suggest that oyster mushroom lowers the level of fats or lipids in the blood. However, a clinical trial did not find such benefits in HIV patients who had high cholesterol levels caused by antiretroviral treatment.
  • Diabetes
    Studies in mice and humans suggest that oyster mushroom may lower blood sugar levels and increase insulin levels. More studies are needed to confirm these effects.
• Do Not Take If
  • You are allergic to mushrooms.
• Side Effects

  Case reports

  • Occupational asthma, widespread lung inflammation: Following exposure to oyster mushroom spores.
• Scientific Name

  Pleurotus ostreatus

• Clinical Summary

  Oyster mushroom is an edible fungus found widely in North America and Europe. It is used in traditional medicine to treat infections, hyperlipidemia, diabetes, and cancer.

  In vitro experiments and studies done in mice have shown that oyster mushroom has antitumor ^{(1) (7) (8) (9) (12) (13)}, immunomodulatory ^(10) (11), antifungal ⁽²⁾, lipid-lowering, and hypoglycemic ^(3) (6) properties. Beneficial effects are due to constituents such as polysaccharides, lectins, and peptides.

  In a study of HIV patients with antiretroviral treatment-induced hypercholesterolemia, oyster mushroom was not effective in lowering non-HDL cholesterol ⁽⁵⁾. However pleuran, a beta-glucan isolated from oyster mushroom, demonstrated anti-allergic effects in children with respiratory tract infections ⁽¹⁷⁾. In type 2 diabetic patients, an oyster mushroom preparation reduced postprandial serum glucose levels and increased serum insulin levels ⁽¹⁹⁾.

• Food Sources

  Oyster mushroom is an edible fungus, available both in fresh and dried forms. The whole mushroom is often used in soups and sauces.

• Purported Uses
  • Cancer treatment
  • Diabetes
  • Hyperlipidemia
  • Infections
• Mechanism of Action

  Pleurostrin, a peptide derived from the fruiting bodies of oyster mushroom, exhibited antifungal properties ⁽²⁾. Mevinolin, another compound, decreased cholesterol biosynthesis by inhibiting HMG CoA reductase, which is the rate-limiting enzyme in cholesterol biosynthesis ⁽³⁾. Ostreolysin, a cytolytic protein isolated from oyster mushroom, caused bradycardia, myocardial ischemia and ventricular extrasystoles following intravenous injection in mice ⁽¹⁴⁾. Suggested hypoglycemic mechanisms include increased glucokinase activity and insulin secretion, which increases glucose utilization by peripheral tissues, inhibits glycogen synthase kinase, and promotes glycogen synthesis ⁽¹⁹⁾.

  A lectin isolated from the fruiting bodies of oyster mushroom demonstrated antitumor activity in mice bearing sarcoma and hepatoma ⁽¹⁾. Another study found that the development of precancerous aberrant crypt foci (ACF) was significantly reduced in mice that were fed a diet containing 10% pleuran, a beta-glucan isolated from oyster mushroom ⁽⁴⁾. RNase Po1, a guanylic acid-specific ribonuclease (a RNase T1 family RNase) from oyster mushroom has been shown to induce apoptosis in tumor cells ⁽¹⁸⁾.

• Contraindications

  Hypersensitivity to oyster mushrooms.

• Adverse Reactions

  Case reports

  • Occupational asthma and allergic alveolitis: Following exposure to oyster mushroom spores  ^(15) (16).
• References

  1. Wang H, Gao J, Ng TB. A new lectin with highly potent antihepatoma and antisarcoma activities from the oyster mushroom Pleurotus ostreatus. Biochem Biophys Res Commun 2000; 275(3):810-816.

  2. Chu KT, Xia L, Ng TB. Pleurostrin, an antifungal peptide from the oyster mushroom. Peptides 2005 Jul;66(1):1-8.

  3. Hossain S, et al. Dietary mushroom (Pleurotus ostreatus) ameliorates atherogenic lipid in hypercholesterolaemic rats. Clin Exp Pharmacol Physiol 2003; 30(7):470-475.

  4. Bobek P and Galbavy S. Effect of pleuran (beta-glucan from Pleurotus ostreatus) on the antioxidant status of the organism and on dimethylhydrazine-induced precancerous lesions in rat colon. Br J Biomed Sci 2001; 58(3):164-168.

  5. Abrams DI, Couey P, Shade SB, et al. Antihyperlipidemic effects of Pleurotus ostreatus (oyster mushrooms) in HIV-infected individuals taking antiretroviral therapy. BMC Complement Altern Med. 2011 Aug 10;11:60.

  6. Chorvathova V, et al. Effect of oyster fungus on glycaemia and cholesterolaemia in rats with insulin-dependent diabetes. Physiol Res 1993; 42(6):175-9.

  7. Wasonga CG, Okoth SA, Mukuria JC, Omwandho CO. Mushroom polysaccharide extracts delay progression of carcinogenesis in mice. J Exp Ther Oncol. 2008;7(2):147-52.

  8. Jedinak A, Sliva D. Pleurotus ostreatus inhibits proliferation of human breast and colon cancer cells through p53-dependent as well as p53-independent pathway. Int J Oncol. 2008 Dec;33(6):1307-13.

  9. Chen JN, Wang YT, Wu JS. A glycoprotein extracted from golden oyster mushroom Pleurotus citrinopileatus exhibiting growth inhibitory effect against U937 leukemia cells. J Agric Food Chem. 2009 Aug 12;57(15):6706-11.

  10. Shlyakhovenko V, Kosak V, Olishevsky S. Application of DNA from mushroom Pleurotus ostreatus for cancer biotherapy: a pilot study. Exp Oncol. 2006 Jun;28(2):132-5.

  11. Sarangi I, Ghosh D, Bhutia SK, et al. Anti-tumor and immunomodulating effects of Pleurotus ostreatus mycelia-derived proteoglycans. Int Immunopharmacol. 2006 Aug;6(8):1287-97.

  12. Martin KR, Brophy SK. Commonly consumed and specialty dietary mushrooms reduce cellular proliferation in MCF-7 human breast cancer cells. Exp Biol Med (Maywood). 2010 Nov;235(11):1306-14.

  13. Jedinak A, Dudhgaonkar S, Jiang J, Sandusky G, Sliva D. Pleurotus ostreatus inhibits colitis-related colon carcinogenesis in mice. Int J Mol Med. 2010 Nov;26(5):643-50.

  14. Zuzek MC, Macek P, Sepciæ K, Cestnik V, Frangez R. Toxic and lethal effects of ostreolysin, a cytolytic protein from edible oyster mushroom (Pleurotus ostreatus), in rodents. Toxicon. 2006 Sep 1;48(3):264-71.

  15. Vereda A, Quirce S, Fernández-Nieto M, Bartolomé B, Sastre J. Occupational asthma due to spores of Pleurotus ostreatus. Allergy. 2007 Feb;62(2):211-2.

  16. Mori S, Nakagawa-Yoshida K, Tsuchihashi H, et al. Mushroom worker’s lung resulting from indoor cultivation of Pleurotus ostreatus. Occup Med (Lond). 1998 Oct;48(7):465-8.

  17. Kobayashi H, Motoyoshi N, Itagaki T, et al. The inhibition of human tumor cell proliferation by RNase Pol, a member of the RNase T1 family, from Pleurotus ostreatus. Biosci Biotechnol Biochem. 2013;77(7):1486-91.

  18. Jesenak M, Hrubisko M, Majtan J, Rennerova Z, Banovcin P. Anti-allergic effect of pleuran (β-glucan from Pleurotus ostreatus) in children with recurrent respiratory tract infections. Phytother Res. 2014 Mar;28(3):471-4.

  19. Jayasuriya WJ, Wanigatunge CA, Fernando GH, et al. Hypoglycaemic activity of culinary Pleurotus ostreatus and P. cystidiosus mushrooms in healthy volunteers and type 2 diabetic patients on diet control and the possible mechanisms of action. Phytother Res. Feb 2015;29(2):303-309.