alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes.

Abstract

Amatoxin poisoning is caused by mushroom species belonging to the genera Amanita, Galerina and Lepiota with the majority of lethal mushroom exposures attributable to Amanita phalloides. High mortality rate in intoxications with these mushrooms is principally a result of the acute liver failure following significant hepatocyte damage due to hepatocellular uptake of amatoxins. A wide variety of amatoxins have been isolated; however, α-amanitin (α-AMA) appears to be the primary toxin. Studies in vitro and in vivo suggest that α-AMA does not only cause hepatocyte necrosis, but also may lead to apoptotic cell death. The objective of this study was to evaluate the complex hepatocyte apoptosis in α-AMA cytotoxicity. All experiments were performed on primary cultured canine hepatocytes. The cells were incubated for 12 h with α-AMA at a final concentration of 1, 5, 10 and 20 μM. Viability test (MTT assay), apoptosis evaluation (TUNEL reaction, detection of DNA laddering and electron microscopy) were performed at 6 and 12 h of exposure to α-AMA. There was a clear correlation between hepatocyte viability, concentration of α-AMA and time of exposure to this toxin. The decline in cultured dog hepatocyte viability during the exposure to α-AMA is most likely preceded by enhanced cellular apoptosis. Our results demonstrate that apoptosis might contribute to pathogenesis of the severe liver injury in the course of amanitin intoxication, particularly during the early phase of poisoning.

Mycetism: A Review of the Recent Literature

“…Gastrointestinal epithelial cells, hepatocytes, and proximal tubular cells are very susceptible to amatoxins, in part, due to increased amatoxin uptake via organic anion-transporting polypeptides within cell membranes [19,35,89]. Alpha-amanitin may also be transported into the cell via Na+−taurocholate cotransporter polypeptides [19].…”

“…Alpha-amanitin may also be transported into the cell via Na+−taurocholate cotransporter polypeptides [19]. Ultimately, hepatic necrosis and acute tubular necrosis of the kidneys ensue [35,89,95].…”

Include mushroom in daily diet—A strategy for better hepatic health

“…Around 15% of the bioactive substances, are presently derived from mycelial extracts of mushrooms (65) , but this fraction tends to increase considering the positive results that were (66) . Recent scientific investigations on different mushrooms extract and their metabolites revealed its importance in the treatment of different human ailments (67)(68)(69)(70)(71)(72)(73) .…”

The evaluation and comparison of the alpha and beta amanitin toxicity on MCF-7 cell line

“…The MTT assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] was used to evaluate the overall functional integrity and viability of the cultured cells (17). The MCF-7 cells were put into 96-well plates (2 × 10 4 for each well), which were incubated for 24 h. The specific concentrations of α-AMA and β-AMA were added to the cell culture medium, and plates were incubated for an additional 36 h. MTT solution (1:10 ratio) and dimethyl sulfoxide (DMSO) (100 µL) were then added to the cell culture medium and plates were incubated overnight.…”

“…The damage to the liver and kidneys caused by α-AMA depends on the received dose. The mortality rate after digestion is very high, and irreversible liver failure may result in death within 3 to 7 days (17).…”