• Biomolecules & Therapeutics
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• 제16권2호
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• pp.100-105
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• 2008

The sphingolipid metabolites act as lipid mediator for cell proliferation and apoptosis in mammalian cells. In bacteria, sphingolipid metabolism remains unknown. The purpose of this study was to investigate whether sphingolipid metabolism is potential target for fumonisin $B_1$($FB_1$) and desipramine in Sphingomonas chungbukensis, Gram-negative bacteria, by comparing the intracellular contents of bacterial sphingolipids with ones of HIT-T15 ${\beta}$-cells, hamster pancreatic cells. The concentrations of ceramide and dihydroceramide were 18.0 ${\pm}$ 12.0 and 0.025 ${\pm}$ 0.018 nmol/mg protein, respectively, in HIT-T15 cells. However, the concentrations of ceramide and dihydroceramide in the bacterial culture were 2.0 ${\pm}$ 1.2 and 10.6 ${\pm}$ 5.5 nmol/mg protein, respectively. $FB_1$ decreased the level of ceramide from 18.0 to 3.8 nmol/mg protein in HIT-T15 ${\beta}$-cells. However, dihydroceramide content in $FB_1$-treated HIT-T15 cells was slightly decreased compared with the control culture. When S. chungbukensis was treated with either $FB_1$ or desipramine, dihydroceramide level was increased by 5- and 4-fold, respectively, compared with the control bacteria. These results indicate that $FB_1$ and desipramine may act as an activator in bacterial sphingolipid biosynthetic pathway, and bacterial sphingolipid metabolism pathway appears to be different from the pathway of mammalian cells.

• Animal cells and systems
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• 제13권3호
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• pp.275-281
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• 2009

The effects of pentylenetetrazol (PTZ), a GABA receptor antagonist, were studied on passive avoidance learning and expression of heat shock protein 70 (hsp70), neuroglobin, and fatty acid binding protein-7 (fabp-7) genes. Zebrafish were trained to stay in a dark compartment to avoid a weight dropping in an acryl shuttle box with a central sliding door. In two training sessions of 2 h interval, each consisting of 3 trials, the crossing time was significantly increased from $43.2{\pm}14.4s$ to $149.3{\pm}38.5s$ in the first training session and remained $116.1{\pm}36.0s$ s in the first trial of the second training session in the control. In zebrafish treated with PTZ before the first training session, the crossing time was significantly increased neither in the first nor in the second training session. However, the increased crossing time was maintained in the second training session when 10 mM PTZ was treated three times for 10 min at 30 min intervals between the first and second training session. Quantitative real-time PCR showed that expression level of hsp70 mRNA increased two to eight fold over that of control in the brain at 0-24 h after termination of PTZ treatment. No change in expression of neuroglobin and fabp-7 mRNA was shown in PTZ-treated zebrafish. Our studies suggest that PTZ impairs learning ability in avoidance response and also modifies expression of genes related to the neuroprotection.

• Radiation Oncology Journal
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• 제13권1호
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• pp.79-85
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• 1995

Purpose : To assess the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor(GM-CSF) in the neutropenia by radiotherapy. Materials and Methods : Eleven patients with various solid tumor were treated with a daily subcutaneous dose of GM-CSF(3-7microgram/kg) for 5days during the radiotherapy. Before and during the course of the study all the patients were monitored by the recording of physical examination, the complete blood count with differential and reticulocyte count and liver function test. Eight patients received prior or concurrent chemotherapy. Results : In 10 patients, the neutrophilic nadir was significantly elevated and the lenght of time that Patients had a neutrophil count below $10^3/mm^3$ a threshold known to be critical to acquiring infective complications was shortened following GM-CSF injection. A significant rise (two fold or greater) of neutrophil count was seen in 10 of 11 patients. In most patients, discontinuation of GM-CSF resulted in a prompt return of granulocyte counts toward baseline. However the neutrophil count remained elevated over $10^3/mm^3$ during radiation therapy, and radiotherapy delays were avoided. Other peripheral blood components including monocytes and platelets also increased after GM-CSF treatment. No significant toxicity was encountered with subcutaneous GM-CSF treatment. Conclusion : GM-CSF was well tolerated by subcutaneous route and induced improvement in the neutropenia caused by radiotherapy.

• Biomolecules & Therapeutics
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• 제3권1호
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• pp.85-90
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• 1995

Phenol, acetaminophen (AA) and salicylamide are all known to be sulfated in rats and mice. We have previously demonstrated that capacity-limited sulfation of xenobiotics in rats is due to the reduced availability of hepatic 3'-phosphoadenosine 5'-phosphosulfate (PAPS), the cosubstrate for sulfation, which in turn is limited by the availability of its precursor, inorganic sulfate. Because species differences have been reported in the extent of sulfation, this study was conducted to determine whether these xenobiotics lower hepatic PAPS and sulfate in ICR mice. All three substrates decreased serum sulfate concentrations in a dose- and time-dependent manner. However, contrary to the observations in rats, phenol markedly increased hepatic PAPS concentrations in a dose-dependent manner, 1 hr after ip injection of 0∼4 mmol/kg. Following ip injection of 4 mmol/kg phenol, hepatic PAPS concentraions were enhanced 2∼3 fold, 0.5-2 hr after dosing and returned to control values 3 hr after dosing, whereas AA and salicylamide had little effect on hepatic PAPS concentraions. In summary, these studies demonstrate that phenol markedly enhances hepatic PAPS concentrations in mice, whereas hepatic PAPS levels are not affected by AA and salicylamide. Our data suggest that 1) hepatic sulfation for high dosages of xenobiotics in ICR mice is not limited by the availability of cosubstrate and 2) there are significant species differences in the regulation of PAPS between rats and mice.

• Parasites, Hosts and Diseases
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• 제30권3호
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• pp.191-200
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• 1992

한국산 유혈목이에서 스파르가눔 충체를 수집하고, 이들 충체의 추출액에서 ion-exchange chromatography와 affinity chromatography를 실시하여 cysteine proteinase를 순수 정제하였다. 경제된 효소의 최적 pH는 5.5이었고, 최적 mole 농도는 0.IM (0.1M sodium acetate, pH5.5) 이었다. 정제된 대소는 thiol-dependent이고, $4^{\circ}C$에서 pH 5.0일 때 24시간 동안 안전성을 보였다. 효소의 환성도는 저분자 합성기질인 CBZ-phe-arg-AFC에 대 해 활성이 높았다. 정제된 효소는 척추동물의 산성 cysteine proteinase의 억제인자에 감수성을 보였다. UItrogel AcA54 column chromatography로 정제된 cysteine proteinase의 분자량을 측정한 결과 28,000 dalton이었다. 정제된 효소는 collagen type I과 hemoglobin을 분해하였다. Immunoblot한 결과 정제된 효소는 스파르가눔증 환자의 혈청과 반응하였다. 이상의 결과에서 스파르가눔의 cysteine proteinase는숙주 체내이동, 조직침수성 및 영양소 섭취에 관여할 것이라 추정되며, 정제된 효소는 스파르가눔 현중의 혈청학적 진단에 이용될 수 있을 것으로 생각된다.

• Biomolecules & Therapeutics
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• 제18권3호
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• pp.343-349
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• 2010

This study was designed to investigate the effects of ticlopidine on the pharmacokinetics of carvedilol after oral or intravenous administration of carvedilol in rats. Carvedilol was administered orally (3 mg/kg) or intravenously (1 mg/kg) without or with oral administration of ticlopidine (4, 12 mg/kg) to rats. The effects of ticlopidine on P-glycoprotein (P-gp) and cytochrome P450 (CYP) 2C9 activity were also evaluated. Ticlopidine inhibited CYP2C9 activity in a concentration-dependent manner with 50% inhibition concentration ($IC_{50}$) of $25.2\;{\mu}M$. In addition, ticlopidine could not significantly enhance the cellular accumulation of rhodamine 123 in MCF-7/ADR cells overexpressing P-gp. Compared with the control group (given carvedilol alone), the area under the plasma concentration-time curve (AUC) was significantly (12 mg/kg, p<0.05) increased by 14-41%, and the peak concentration ($C_{max}$) was significantly (12 mg/kg, p<0.05) increased by 10.7-73.3% in the presence of ticlopidine after oral administration of carvedilol. Consequently, the relative bioavailability (R.B.) of carvedilol was increased by 1.14- to 1.41-fold and the absolute bioavailability (A.B.) of carvedilol in the presence of ticlopidine was increased by 36.2-38.5%. Compared to the i.v. control, ticlopidine could not significantly change the pharmacokinetic parameters of i.v. administered carvedilol. The enhanced oral bioavailability of carvedilol may result from inhibition of CYP2C9-mediated metabolism rather than P-gpmediated efflux of carvedilol in the intestinal and/or in liver and renal eliminatin of carvedilol by ticlopidine.

• 한국버섯학회지
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• 제15권4호
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• pp.168-177
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• 2017

To evaluate effects of ligninolytic enzyme type on the mycelial response and ligninolytic enzyme production during interspecific interactions among wood-rotting fungi, 4 fungal strains, Trichophyton rubrum LKY-7, Trichophyton rubrum LSK-27, Pycnoporus cinnabarinus, and Trichoderma viride, were selected. Regarding ligninolytic enzyme production, LKY-7 secreted laccase and manganese peroxidase (MnP), P. cinnabarinus secreted only laccase, and LSK-27 secreted only MnP in glucose-peptone medium, while T. viride did not produce any ligninolytic enzymes. In the co-culture of LKY-7 with P. cinnabarinus, the formation of aerial mycelium was observed and the enhancement of laccase activity owing to interspecific interaction appeared to be very low. In the co-culture of LKY-7 and P. cinnabarinus with LSK-27, a hypha-free clear zone was observed, which resulted in deadlock, and increased laccase or MnP activity was detected at the interaction zone. The interaction responses of LKY-7, P. cinnabarinus, and LSK-27 with T. viride were characterized by the formation of mycelial barrages along the interface. As mycelial barrages were observed at the T. viride territory and no brownish pigment was observed in the mycelial barrages, it is suggested that laccase and MnP are released as part of an offensive response, not as a defensive response. The co-culture of P. cinnabarinus with T. viride lead to the highest enhancement in laccase activity, yielding more than 14-fold increase in laccase activity with respect to the mono-culture of P. cinnabarinus. MnP activities secreted by LKY-7 or LSK-27 was generally low in interspecific interactions.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.127-134
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• 1984

As a series of studies to clarify clonorchicidal substances in body surface mucus of some freshwater fishes, the substance in the epidermal mucus of Cyprinus carpio was isolated by silica gel column and thin layer chromatography and analysed for its chemical nature. Wormicidal trial was done in vitro, and the results obtained are summarized as follows: The mucus was extracted by ethyl ether and separated into 4 fractions by column chromatography using benzene as solvent. The second fraction with yellowish red colour among them showed the strongest clonorchicidal effect. The yellowish red fraction obtained by column chromatography was then fractionated into 6 spots by thin layer chromatography with petrol/ etherjchloroform (30/70, v/v), and the Rf. 0.714 spot among the 6 spots showed the strongest effect. The Rf. 0.714 spot was further fractionated into 6 spots by thin layer chromatography with benzene/acetone (90/10, vlv), and the Rf. 0.800 spot among the later 6 spots revealed the strongest effect. The Rf. 0.800 spot was chromatographed on column with benzene and 2 fractions were obtained. The second fraction of light brown colour represented the final purified fraction. By these Purification Procedures, clonorchicidal substance was Purified 15-fold with 0.035 yield from the mucus of C. carpio, and 10mg of the final fraction killed the cercaria in 26 min, the metacercaria in 115 min, and the adult in 443 min. Infra red and nuclear magnetic resonance spectrometric analysis of the purified substance revealed that the substance belongs to an ethyl ester of unsaturated fatty acid with 2 double bonds, 15 methylene groups and 1 methyl group.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1310-1316
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• 2005

To evaluate the toxicological properties of human cytochrome P450 2E1 (CYP2E1) induced by ethanol and possible protective effects of various green tea catechins on alcohol-induced toxicity, transfected HepG2 cells that stably and constitutively express human CYP2E1 were established using the recombinant retroviral expression vector. Exposure of the CYP2E1-expressing HepG2 cells to high concentration of ethanol (200 mM) for 5 days resulted in a more than $50\%$ increase of cytotoxicity, assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction, lactate dehydrogenase (LDH) release, and reactive oxygen species (ROS) production, and loss of normal morphology, in comparison with HepG2 cells containing control vector. Treatment of the cells with various catechins increased cell viability by more than 2-fold. (-)-Epicatechin gallate and(-)-catechin gallate at the lowest concentration ($5\;{\mu}M$) attenuated cell death induced CYP2E1 by $60-65\%$. Therefore, the results showed that the catechins, including epimerized catechins, have strong protective effects against alcohol-induced CYP2E1 toxicity, and it is correlated with antioxidant effect.

• Journal of Microbiology and Biotechnology
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• 제26권10호
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• pp.1781-1789
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• 2016

Glargine insulin is a long-acting insulin analog that helps blood glucose maintenance in patients with diabetes. We constructed the pPT-GI vector to express prepeptide glargine insulin when transformed into Escherichia coli JM109. The transformed E. coli cells were cultured by fed-batch fermentation. The final dry cell mass was 18 g/l. The prepeptide glargine insulin was 38.52% of the total protein. It was expressed as an inclusion body and then refolded to recover the biological activity. To convert the prepeptide into glargine insulin, citraconylation and trypsin cleavage were performed. Using citraconylation, the yield of enzymatic conversion for glargine insulin increased by 3.2-fold compared with that without citraconylation. After the enzyme reaction, active glargine insulin was purified by two types of chromatography (ion-exchange chromatography and reverse-phase chromatography). We obtained recombinant human glargine insulin at 98.11% purity and verified that it is equal to the standard of human glargine insulin, based on High-performance liquid chromatography analysis and Matrix-assisted laser desorption/ionization Time-of-Flight Mass Spectrometry. We thus established a production process for high-purity recombinant human glargine insulin and a method to block Arg (B31)-insulin formation. This established process for recombinant human glargine insulin may be a model process for the production of other human insulin analogs.