• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.18-25
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• 2003

Effects of tributyltin chloride (TBTC) in vitro on mixed function oxygenase (MFO) system on liver microsome of eight marine fish species were investigated. To determine the effects on MFO system, cytochrome P45O (CYP) and cytochrome b5 con-tents, activities of two reductases (NADH-cytochrome b5 reductase and NADPH-cy-tochrome P450 reductase) and four dealkylation enzymes (EROD, PROD, MROD and ECOD) were measured in fish microsoms exposed to TBTC for 20 min. The WP content was reduced to 10% of the control group in 6 out of 8 species exposed to TBTC, whereas there was no significant change in the cytochrome bs content. the response of NAD(P)H dependant reductases depended on fish species. The dealkylation enzyme activities in microsome were also apparently inhibited by TBTC. The degree of inhibition was different among fish species and four enzymes. The EROD activities in eight species were decreased to the range of 1∼65% of control group.

• BMB Reports
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• v.30 no.4
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• pp.237-239
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• 1997

The effects of trichloroethylene (TRI) on the induction of cytochrome P-450 (CYP) and several other related enzymes in Sprague Dawley rats were investigated Rats were treated with TRI 150. 300. 600 mg/kg body weight in corn oil intra peritoneally once a day for 2 days. The total contents of microsomal CYP and cytochrome $b_5\;(b_5)$ decreased with the increase of TRI concentration. but the activity of p-nitrophenol hydroxylase increased with the increase of TRI dosage (p<0.05). Western blot analysis which utilized monoclonal antibodies against CYP2E1 also showed a significant increase in the CYP2E band density. The increase of the activity of pentoxyresolufin-O-deethylase also was observed with the TRI treatment (p<0.05) although there was no significant increase in the cytochrome CYP2B1/2 in Western blotting The TRI did not affect the induction of aryl hydrocarbon hydroxylase. These findings suggest that the CYP2E1 is the primary enzyme which could be induced by TRI treatment in rats.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.168-173
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• 1995

To investigate the effects of endosulfan on cytochrome P-450 enzymes in mouse(Balb c.), endosulfan was given by an intraperitoneal dose of 7.5 mg/kg. The treatment of endosulfan increased the cytochrome P-450 content by 3.3 to 4.2 fold, cytochrome $b_5$ content by 2.3 to 3.8 fold, NADPH cytochrome P-450 reductase activity by 5.3 to 6.4 fold and total haem content by 3.1 to 3.6 fold of mouse liver after 48 hrs of intraperitoneal injection. Endosulfan cytochrome P-450 absorption spectrum exhibited miximum at 387 nm and 389 nm and broad near 407 nm in the liver microsome. Reduced P-450-CO spectrum of the liver microsome exposed by the treatment of endosulfan showed maximum at 449 nm and 450 nm compared to that of the control having maximum at 451 nm, which indicated endosulfan induced cytochrome P-450 new isozymes. Aldrin epoxidase activities in the mouse liver and kidney were increased by 2.8 and 2.1 fold by the treatment of endosulfan. Also 7-ethoxyresorufin dealkylase activities in the mouse liver and kidney were elevated by 1.7 and 1.8 fold by treatment of endosulfan.

• Journal of Life Science
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• v.27 no.6
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• pp.617-622
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• 2017

In this study, we sought to develop an effective cloning system by which human cytochrome $b_5$ (cyt $b_5$) is introduced and expressed in zebrafish. First, the 414 bp human cyt $b_5$ gene was amplified from RNA extracts of HeLa cells using RT-PCR, and the amplicon was subsequently sequenced to confirm that it was intact. Next, cyt $b_5$ was cloned into the pEGFP-N3 vector, which also encodes a fluorescent gene. One-cell stage zebrafish embryos were microinjected with the recombinant vector containing the cyt $b_5$ gene. Fluorescence microscopy confirmed high expression of the fluorescent gene in the injected fry compared to the non-fluorescent control fry. Finally, we extracted RNA from the injected fry and performed RT-PCR to determine whether the human cyt $b_5$ gene is expressed in the transgenic zebrafish. Sequencing analysis further confirmed that the cloned human cyt $b_5$ gene was intact. The transgenic zebrafish model produced in this study will be a useful tool to study therapeutic approaches to cure various diseases related to the deficiency of functional human cyt $b_5$ as well as tools for cloning useful genes in fish.

• Archives of Pharmacal Research
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• v.21 no.1
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• pp.35-40
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• 1998

Human cytochrome P450 4F2 shows high regioselectivity in hydroxylation of stearic acid and leukotriene $ B_4.$ As a first step of its regulation study, human cytochrome P450 4F2 genomic DNA was isolated from liver of a person who was administered clofibrate for 10 years. From Southern hybridization, restriction enzyme digestion and sequencing experiments, isolated genomic DNA fragment was found to contain around 32 Kb DNA and more than 20 Kb of $5^I$ end regulatory region. Sequences of the structural gene region revealed exon 1 and exon 2. Further regulation studies would elucidate the feedback mechanisms of the oxidative degradation of fatty acids, inflammatory response and the clearance of leukotriene B4 in the liver. Furthermore, regulation study of this gene could explain the species difference in responses to peroxisome proliferator and help in the safety evaluation of peroxisome proliferating chemicals to human being.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.414-422
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• 2004

To infer phylogenetic relationships among Epinephelus species inhabiting coastal regions of Korean peninsula, mitochondrial cytochrome b genes from 9 species belonging to the subfamily Epinephelinae were PCR-amplified, cloned and sequenced. Aligned cytochrome b sequences of 10 species containing one additional sequence from GenBank were 1,140 base pairs in length, including 439 variable and 330 parsimony informative sites. The cytochrome b genes of 10 species, as other vertebrates studied to date, exhibit unequal base compositions: an entirely low G content ($15.2{\pm}0.3{\%}$on average) and almost equal T, C and A contents ($29.3{\pm}0.8{\%},\;30.7{\pm}1.0{\%},\;and\;24.8{\pm}0.5{\%}$ on average, respectively).In third codon positions, transitional substitutions especially between Epinephelus species and outgroup species are almost certainly saturated or near saturation. Phylogenetic analyses were performed with sequence data from 8 Epinephelus species and 2 outgroup species (Cephalopholis urodela and Vaviola louti) by using distance-based (neighbor-joining and minimum evolution) and parsimony-based (maximum parsimony) methods. The results showed that the monophyly of the genus Epinephelus was supported by relatively high bootstrap values. However, phylogenetic relationships among E. areolatus, E. moara, E. septemfasciatus, and Epinephelus sp were poorly resolved. Within the genus Epinephelus, three resolved monophyletic groups were found: clade 1 included E. akaara and E. awoara;, clade 2 included E. fasciatus and E. merra; and clade 3 included E. akaara, E. awoara, E. fasciatus, E. merra, E. areolatus, E. moara, E. septemfasciatus and Epinephelus Sp.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.699-707
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• 1995

Eurasian yellow perch (Perca fluviatilis) and American yellow perch (Perca flavescens) are known to be endemic species in Eurasia and North America, respectively. The presence of endemic species on each continent suggests their independent evolutionary history. However, because of the morphological similarity, distribution pattern, and only recent fossil record, their divergence time and speciation of the two Perca species has long been controversial. Here, from the comparison of the entire nucleotide sequences of cytochrome b gene, large genetic divergence between the two Perca species is observed although they are morphologically similar each other. Among 1,140 base pairs, interspecific nucleotide differences are found at 130 sites $(11.4\%)$. The differences varies with codon position, showing 22 sites in the first, 5 sites in the second, and 103 sites in the third codon position. Considering the types of nucleotide changes, transitional differences are much more than transversional differences and its ratio turned out to be 5.19. The estimated divergence time of the two Perca species indicates that they were separated each other approximately in the late Miocene period, which implies the long history of speciation. With comparison of the inferred amino acid sequences, strong structural and functional constraints which seem to be maintained by the highly conservative amino acid residues or protein regions, as found in other taxonomic groups of organisms, are also recognized in the cytochrome b of the fishes examined.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.43-48
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• 2004

• Proceedings of the Korean Society of Toxicology Conference
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• 2004.05a
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• pp.43-48
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• 2004

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.684-692
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• 2002

Cordyceps militaris has been known as a Chinese traditional medicine for the treatment of tuberculosis, asthma, kidney disease, debility and fatigue etc. This study was attempted to investigate the therapeutic effect of C. militaris extract on the cytotoxic activity of HepG2, human hepatocellular carcinoma cells and the liver damage induced by carbon tetrachloride in SD rats. C. militaris extracts inhibited significantly the proliferation of HepG2 cells in vitro. Carbon tetrachloride(CCl₄) caused a significant an increase in liver weight, serum aspartate aminotransferase(AST) and alanine aminotransferase(ALT) activity, alkaline phosphatase(ALP), serum thiobarbituric acid reactive substances (TBARS), microsomal TBARS, and decrease in microsomal detoxification enzymes (cytochrome P-450, P-450 reductase, cytochrome b5, b5 reductase). TBARS and ALP in serum pretreated with C. militaris extracts (300mg/kg/day, 600mg/kg/day) was significantly reduced compared to control group(CCl₄). Cytochrome b5 and b5 reductase activities were significantly increased in CM300 (300 mg/kg/day) and CM600 group(600 mg/kg/day), and cytochrome P-450 reductase was significantly increased in CM300 group. Pretreatment (100, 300, and 600 mg/kg/day for 7 days) of C. militaris with CCl₄ was significantly inhibited the accumulation microsomal TBARS and the significantly increased in the cytochrome P-450 activity. These results suggested that C. militaris (300mg/kg/day for 7 days) has appreciable therapeutic effect on CCl₄ induced hepatotoxicity.