• Journal of Microbiology and Biotechnology
• /
• 제10권3호
• /
• pp.375-380
• /
• 2000

The preliminary screening of several cyanobacteria, using mice bioassay, reveale the production of a hepatotoxin by the cyanobacterium Scytonema sp. strain BT 23 isolated from soil. An intraperitoneal injection of the crude toxin (LD50 56 mg/kg body wt) from this strain caused the death of the mice within 40 min, and the anmals showed slinical signs of mice within 40 min, and the animals showed clinical signs of hepatotoxicity. The toxin was purified and partially characterized. The active fraction appears to be nonpolar in nature and shows absorption peaks at 240 and 285 nm. The purified toxin had an LD50 of TEX>$100<\mu\textrm{g}/kg$ body wt and the test mice died within 40 min of toxin administration. The toxin-treated mice showed a 1.65-fold increase in liver weight at 40 min and the liver color chnged to dark red due to intrahepatic hemorrhage and pooling of blood. Furthermore, the administration of the toxin to test mice induced a 2.58, 2.63, and 2.30-fold increse in the activity of the serum enzymes alanine aminotransferase, lactate dehydrogenase, and alkaline phosphatase, respectively. Further experiments with the 14C-labeled toxin revealed a maximum accumulation of the toxin in the liver. The clinical symptoms in the mice were similar to those produced by microcystin-L.R. These results suggest that hepatotoxins may also be produced in non bloom-forming planktonic cyanobacteria.

• Journal of Microbiology and Biotechnology
• /
• 제9권1호
• /
• pp.9-21
• /
• 1999

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
• /
• pp.148-148
• /
• 2002

This study is to characterize the microscopical and ultrastructural changes in chronic exposure of Microcystin-LR (MCLR), a cyclic heptapeptide hepatotoxin, comparing to those in acute lethal toxicity. Female ICR mice were injected intraperitoneally with 10, 20, 30,$\mu\textrm{g}$/kg of MCLR every 3 day for 27 days.(omitted)

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
• /
• pp.214.1-214.1
• /
• 2003

Metabonomic analysis using Liquid Chromatography-Mass Spectrometry (LC-MS) was employed to test the feasibility to predict chemical-induced toxicity. Time-dependent metabolic variations were evaluated in rats treated with the model hepatotoxin, ${\alpha}$- naphthylisothiocyanate (ANIT). Urine samples of ANIT treated group and control group were collected up to 7 days postdose. Urine samples were analyzed by gradient HPLC combined with electrospray mass spectrometry. The chromatographic results were data-reduced and analyzed using principal component analysis to show the time dependent biochemical variations induced by ANIT toxicity. (omitted)

• 미생물학회지
• /
• 제47권3호
• /
• pp.268-274
• /
• 2011

남조세균 Anabaena (Cyanobacteria, Nostocales)는 담수 생태계에서 녹조 현상을 유발하거나 일부 종은 간독소(hepatotoxin)를 갖고 있어 수질관리 차원에서 주목 받아 왔다. 본 연구는 Anabaena RNA polymerase beta subunit (rpoB) 유전자 염기서열을 규명하였으며, 분류학적 분자 마커로 사용하기 위하여 이들 염기서열의 특성을 평가하였다. Anabaena rpoB 유전자는 16S rRNA 유전자와 비교하여 염기 유사도가 낮으며 유전자 변이가 큰 것으로 분석되었으며, 통계적으로 유의한 차이를 보였다(Student t-test, p<0.01). Parsimony 분석을 통해 rpoB 유전자가 4.8배의 속도로 빠르게 진화하는 것으로 파악되었다. 또한 rpoB 유전자 phylogeny 분석에서 16S rRNA tree보다 높은 해상도로 Anabaena 균주를 명확하게 구분해 주었다. 본 연구 결과는 Anabaena의 종 식별, 분자계통 분류, 분자적 검출을 위해 rpoB 유전자가 매우 효과적이라는 것을 제시해 준다.

• Molecular & Cellular Toxicology
• /
• 제2권2호
• /
• pp.120-125
• /
• 2006

Phenytoin is an anti-epileptic. It works by slowing down impulses in the brain that cause seizures. The recent microarray technology enables us to understand possible mechanisms of genes related to compounds which have toxicity in biological system. We have studied that the effect of a compound related to hepatotoxin in vitro system using a rat whole genome microarray. In this study, we have used a rat liver epithelial cell line WB-F344 and phenytoin as a hepatotoxin. WB-F344 was treated with phenytoin for 1 to 24 hours. Total RNA was isolated at times 1, 6 and 24h following treatment of phenytoin, and hybridized to the microarray containing about 22,000 rat genes. After analysis with clustering methods, we have identified a total of 1,455 differentially expressed genes during the time course. Interestingly, about 1,049 genes exhibited differential expression pattern in response to phenytoin in early time. Therefore, the identification of genes associated with phenytoin in early response may give important insights into various toxicogenomic studies in vitro system.

• Toxicological Research
• /
• 제22권4호
• /
• pp.375-380
• /
• 2006

Microcystin-LR (MC-LR) is a cyanobacterial hepatotoxin mainly produced by Microcystis aeruginosa. The current study examined the effects of a single intraperitoneal dose of MC-LR in rats. Female Sprague-Dawley rats were intraperitoneally injected with MC-LR ($100{\mu}g/kg$ body weight) and they were sacrificed at 0, 20, 40, 80, 160 min, or 12 h after injection. Clinically, animals showed lethargy and had ruffled hair beginning at 40 min post injection. In the gross findings, liver was enlarged and its color was changed into dark red beginning at 40 min post injection. Microscopically, dissociation of centrilobular hepatocytes and hemorrhage was observed in the hepatic central legions and such pathological changes were then extended to the portal regions of liver by time course manner. Interestingly at 80 min after MC-LR injection, the entrapped eosinophilic materials that may be necrotic fragments of dissociated hepatocytes were found in the capillaries of lung and renal glomerulus. Ultrastructurally, microvilli of the hepatocytes were disrupted or lost at all time points. Furthermore, the Disse space and gap junctions were widened beginning at 40 min post injection. These results suggest that liver is the major target organ of MC-LR and isolated hepatocytes by the effects of such hepatotoxin may secondarily reduce the physiological function of lung and kidney.

• 동의생리병리학회지
• /
• 제22권5호
• /
• pp.1210-1214
• /
• 2008

The purpose of this study is to investigate the effect of water extract from Artemisiae Argi Folium (WAAF) on hepatotoxicity caused by acetaminophen (AAP) and acetaldehyde which are regarded as hepatotoxin. Artemisiae Argi Folium was known to have the antibacterial, immune-enhancing, and anticoagulative properties. In Korean Medicine, Artemisiae Argi Folium is supposed to be related with 'liver meridian' according to traditional medical theory. AAP and acetaldehyde reduce the intracellular production of hydrogen peroxide ($H_2O_2$) and nitric oxide (NO) production of human hepatocyte HepG2. The intracellular production of hydrogen peroxide ($H_2O_2$) was measured by dihydrorhodamine 123 (DHR) assay. NO production was measured with Griess test. WAAF increased the production of $H_2O_2$ and NO reduced by AAP and acetaldehyde in HepG2 cells. Therefore, It could be suggested that WAAF has the hepatoprotective activity against AAP and acetaldehyde.

• Natural Product Sciences
• /
• 제12권1호
• /
• pp.8-13
• /
• 2006

The present study was carried out to investigate the hepatoprotective effect of the extract of Pterocarpus santalinus Linn on acute hepatotoxicity induced in Wistar albino rats by a single dose of Galactosamine (400 mg/kg). Suspensions of methanolic extract of heartwood of P. santalinus (200 and 400 mg/kg) in 0.3% Carboxy Methyl Cellulose (CMC) were administered p.o. to experimental animals and hepatoprotective activity was monitored by estimating aspartate amino transferase (ASAT, GOT), alanine amino transferase (ALAT, GPT), alkaline phosphatase (ALP), total bilirubin (TB), lactate dehydrogenase (LDH), total cholesterol (TC), triglycerides (TGL), albumin, total protein (TP) levels. The methanolic extract significantly reduced the elevation of serum transaminases and alterations of biochemical parameters induced by hepatotoxin, and alleviated the degree of liver damage. The results were supported by histopathological studies of liver samples showing regeneration of hepatocytes in treated animals. Silymarin (25 mg/kg), a known hepatoprotective drug was used for comparison. Based on the results obtained, it can be concluded that P. santalinus exerts hepatoprotective activity and may serve as a useful adjuvant in several clinical conditions associated with liver damage.

• Biomolecules & Therapeutics
• /
• 제10권1호
• /
• pp.12-18
• /
• 2002

Silymarin and curcumin have been used for supportive treatment of liver disease of difffrent etiology due to their hepatoprotective activities. The present study was carried out to investigate the hepatoprotective efffcts of silymarin and/or curcuma extract against hepatotoxins induced liver injury. To investigate hepatoprotective effects, the silymarin and/or curcuma extract were pre-treated orally to experimental animals. And thereafter a single dose of hepatotoxin, carbon tetrachloride ($CCl_4$) and acetaminophen were administered through oral or intraperitoneal route, respectively. Chronic liver damage was induced by subcutaneous injection of $CCl_4$ for 3 weeks (2 times/week). Hepatoprotective and therapeutic effects were monitored by estimating serurn ALT and AST levels and by measuring hepatic glutathione (GSH) and malondialdehyde (MDA)levels. Collagen type 1 was detected with irnrnunostaining to assess fibrosis. The results showed that the mix-ture of silymarin and curcuma extract significantly reduced serum biochemistry levels and MDA levels com-pared with those of control group in both acute and chronic animal models. In antifibrotic effect, the relative hepatic collagen content was significantly decreased by silymarin and/or curcuma extract treatment. It was concluded that the complex of silymarin and curcuma extract have a both hepatoprotective and therapeutic effect synergically in rat liver injury induced by heptotoxins.