Protective Effect of Diethyldithiocarbamate Pretreatment on Chromium(VI)-Induced Cytotoxicity and Lipid Peroxidation in Primary Cultures of Rat Hepatocytes.

S-adenosylmethionine (SAMe) has been shown to protect hepatocytes from toxic injury, both experimentally-induced in animals and in isolated hepatocytes. The mechanisms by which SAMe protects hepatocytes from injury can result from the pathways of SAMe metabolism. Unfortunately, data documenting the protective effect of SAMe against mitochondrial damage from toxic injury are not widely available. Thioacetamide is frequently-used as a model hepatotoxin, which causes in vivo centrilobular necrosis. Even though thioacetamide-induced liver necrosis in rats was alleviated by SAMe, the mechanisms of this protective effect remain to be verified. The aim of our study was to determine the protective mechanisms of SAMe on thioacetamide-induced hepatocyte injury by using primary hepatocyte cultures. The release of lactate dehydrogenase (LDH) from cells incubated with thioacetamide for 24 hours, was lowered by simultaneous treatment with SAMe, in a dose-dependent manner. The inhibitory effect of SAMe on thioacetamide-induced lipid peroxidation paralleled the effect on cytotoxicity. A decrease in the mitochondrial membrane potential, as determined by Rhodamine 123 accumulation, was also prevented. The attenuation by SAMe of thioacetamide-induced glutathione depletion was determined after subsequent incubation periods of 48 and 72 hours. SAMe protects both cytoplasmic and mitochondrial membranes. This effect was more pronounced during the development of thioacetamide-induced hepatocyte injury that was mediated by lipid peroxidation. Continuation of the SAMe treatment then led to a reduction in glutathione depletion, as a potential consequence of an increase in glutathione production, for which SAMe is a precursor.

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Asiatic Acid Derivatives Protect Primary Cultures of Rat Hepatocytes against Carbon Tetrachloride-Induced Injury via the Cellular Antioxidant System

Natural Product Communications ◽

10.1177/1934578x0900400605 ◽

2009 ◽

Vol 4 (6) ◽

pp. 1934578X0900400

Author(s):

Mi Kyeong Lee ◽

Seung Hyun Kim ◽

Hyekyung Yang ◽

Doo-Yeon Lim ◽

Je-Ho Ryu ◽

...

Keyword(s):

Lipid Peroxidation ◽

Superoxide Dismutase ◽

Antioxidant Enzymes ◽

Carbon Tetrachloride ◽

Primary Cultures ◽

Rat Hepatocytes ◽

Asiatic Acid ◽

Antioxidative Defense ◽

Protective Activity ◽

Defense System

We attempted to elucidate the hepatoprotective mechanism of two asiatic acid (AS) derivatives, 3β,23-dihydroxyurs-2-oxo-12-ene-28-oic acid (AS-10) and 3β,23-dihydroxyurs-12-ene-28-oic acid (AS-14), which exhibited significant protective activity against carbon tetrachloride (CCl4)-induced hepatotoxicity in primary cultures of rat hepatocytes. Our findings showed that AS-10 and AS-14 preserved the level of glutathione and the activities of antioxidant enzymes such as glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase. In addition, these compounds ameliorated lipid peroxidation, as demonstrated by a reduction in the production of malondialdehyde. Furthermore, AS-10 and AS-14 did not restore the reduced total GSH level by BSO, indicating that the hepatoprotective activities of these compounds may be involved, in part, by regulating GSH synthesis. From these results, we suggest that both AS-10 and AS-14 exerted their hepatoprotective activities against CCl4-induced injury by preserving the cellular antioxidative defense system.

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The Effect of D-Galactosamine on Lean and Steatotic Rat Hepatocytes in Primary Culture

Physiological Research ◽

10.33549/physiolres.933225 ◽

2015 ◽

pp. S637-S646 ◽

Cited By ~ 2

Author(s):

O. KUČERA ◽

H. LOTKOVÁ ◽

O. SOBOTKA ◽

Z. ČERVINKOVÁ

Keyword(s):

Lipid Peroxidation ◽

Mitochondrial Membrane ◽

Caspase 3 ◽

Primary Cultures ◽

Rat Hepatocytes ◽

Dependent Manner ◽

Oxygen Species ◽

Ros Formation ◽

Dose Dependent ◽

Higher Sensitivity

The aim of our work was to compare the effect of D-galactosamine (GalN) on primary cultures of lean and steatotic rat hepatocytes isolated from intact and fatty liver, respectively. GalN caused more severe injury to steatotic hepatocytes than to lean cells as documented by lactate dehydrogenase leakage. Necrotic mode of cell death strongly prevails over apoptosis since we did not observe any significant increase in activities of caspase 3, 8 and 9 in any group of hepatocytes treated with GalN. Reactive oxygen species (ROS) formation and lipid peroxidation were elevated in a dose-dependent manner by GalN and were significantly more pronounced in fatty hepatocytes. A decrease in the percentage of hepatocytes with energized mitochondria was observed from 30 mM and 10 mM GalN in lean and steatotic hepatocytes, respectively. Our results undoubtedly indicate that steatotic hepatocytes exert higher sensitivity to the toxic effect of GalN. This sensitivity may be caused by more intensive GalN-induced ROS production and lipid peroxidation and by higher susceptibility of mitochondria to loss of mitochondrial membrane potential in steatotic hepatocytes. In our experimental arrangement, apoptosis does not seem to participate considerably on hepatotoxic action of GalN in either group of hepatocytes.

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