• The Korea Journal of Herbology
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• v.38 no.6
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• pp.45-52
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• 2023

Objectives : Effects of baicalein (BA) on oxidative stress in RAW 264.7 mouse macrophages stimulated with peptidoglycan (PG) and lipopolysaccharide (LPS) were investigated. Methods : RAW 264.7 co-stimulated with LPS and PG were incubated with BA at concentrations of 25 and 50 µM. Incubation time was 18 h, 20 h, 22 h, 24 h, and 26 h. After incubation, the production of hydrogen peroxide in RAW 264.7 was measured with dihydrorhodamine 123 assay. Additionally, RAW 264.7 stimulated with PG were incubated with BA at concentrations of 25 and 50 µM for 24 h. After incubation, NO production was evaluated by griess reagent assay. Results : BA significantly inhibited hydrogen peroxide productions (p <0.05). In details, production of hydrogen peroxide in 'LPS and PG'-stimulated RAW 264.7 treated for 18 h with BA at concentrations of 25 and 50 µM was 91.27% and 89.22% of the control group treated with LPS and PG only, respectively; the production of hydrogen peroxide for 20 h was 92.19% and 90.58%, respectively; production of hydrogen peroxide for 22 h was 91.69% and 89.89%, respectively; production of hydrogen peroxide for 24 h was 92.4% and 90.19%, respectively; production of hydrogen peroxide for 26 h was 91.7% and 89.04%, respectively. Additionally, BA at the concentration of 50 and 100 µM significantly inhibited NO production in PG-induced RAW 264.7 (p <0.05). Conclusions : BA might have anti-oxidative activity related to its inhibition of hydrogen peroxide production in 'LPS and PG'-stimulated RAW 264.7 macrophages.

• The Korean Journal of Physiology
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• v.3 no.1
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• pp.11-18
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• 1969

Tissue homogenates of 10 kinds of human cancer tissues were incubated in medium containing either one of $C^{14}-1,\; C^{14}-2,\;or\; C^{14}-3-lactate $ as a substrate in order to observe the oxidative pathway of lactate in cancer tissues. Lactate concentration in incubation medium was maintained at 50 mg%. At the end of incubation period, gas samples and incubation media were analyzed for total $CO_2$ production rates, radioactivities of respiratory $CO_2$, lactate uptake rates and pyruvate appearance rates. The following results were obtained. 1. Lactate uptake rates in all of cancer tissues examined were less than $2.5\;{\mu}M/hr/gm$ and much lower than those in normal tissues. 2. In the 10 kind of human cancer tissues, total $CO_2$ production rates were less than $10\;{\mu}M/hr/gm$, in all cases. These lower values impressed that oxidative metabolism in tumor tissues generally inhibited as compared with that in normal tissue. On the other hand, fractions of $CO_2$ derived from lactate to total $CO_2$ production rates were less than 15% except one case These facts showed that oxidation of lactate into $CO_2$ was greatly inhibited in tumor tissues. 3. Respiratory $CO_2$ yields from C-1 carbon of lactate in various cancer tissues were mean of 77.7% of total $CO_2$ yield from lactate and $CO_2$ yields from C-2 and C-3 carbon of lactate were mean of 9.1% and 12.6% respectively. These facts showed that carboxyl carbon of lactate oxidized more easily than ${\alpha}\;and\;{\beta}$ carbon of lactate. 4. In 10 kinds of cancer tissues, fractions of disappeared lacteate from media into $CO_2$ and pyruvate, which expressed as RLD $co_2$ and RLDpy respectively, were about 5% in except 3 cases and less than 3% except one case. These fact showed that almost of disappeared lactate from media were degraded into compounds other than $CO_2$ and pyruvate. From the above date, it was suggested that in the oxidative pathway of lactate in cancer tissues $CO_2$ was easily Produced from carboxyl carbon of lactate by oxidative decarboxylation as in the normal tissue, and further oxidation of 2 carbon unit via TCA cycle was inhibited.

• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.507-515
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• 1996

Background : Potassium channel opener (K-opener) opens ATP-sensitive K'-channel located at cell membrane and induces potassium efflux from cytosol, resulting in intracellular hyperpolarization. Newly synthesized K-opener is currently examined for pharmacologic potency by means of rubidium release test from smooth muscle strip pre-incubated with Rb-86. Since in-vivo behavior of thallium is similar to that of rubidium, we hypothesized that K-opener can alter T1-201 kinetics in vivo. Purpose : This study was prepared to investigate the effects of pinacidil (one of potent K-openers) on the T1-201 uptake and clearance in cultured myocyte, and in-vivo biodistribution in mice. Methods : Spontaneous contracting myocytes were prepared to imitate in-vivo condition from 20 hearts of 3-5 days old Sprague-Dawley rat and cultured for 3-5 days before use ($5{\times}10^5$ cells/ml). Pinacidil was dissolved in 10% DMSO solution at a final concentration of 100nM or l0uM and was co-incubated with T1-201 in HBSS buffer for 20-min to evaluate its effect on cellular T1-uptake, or challenged to cell preparation pre-incubated with T1-201 for washout study. Two, 40 or $100{\mu}g$ of pinacidil was injected intravenously into ICR mice at 10 min after $5{\mu}Ci$ T1-201 injection, and organ uptake and whole body retention rate were measured at different time points. Results : Co-incubation of pinacidil with T1-201 resulted in a decrease in T1-201 uptake into cultured myocyte by 1.6 to 2.5 times, depending on pinacidil concentration and activity of T1-201 used. Pinacidil enhanced T1-201 washout by 1.6-3.1 times from myocyte preparations pre-incubated with T1-201. Pinacidil treatment appears to be resulted in mild decreases in blood and liver activity in normal mice, in contrast, renal and cardiac uptake were mildly decreased in a dose dependent manner. Whole body retention ratios of T1-201 were lower at 24 hour after injection with $100{\mu}g$ of pinacidil than control. Conclusion : These results suggest that treatment with K-opener may affect the interpretation of T1-201 myocardial images, due to decreasing thallium accumulation and enhancing washout from myocardium.

• Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.70-74
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• 2001

To examine the production of steroids with potential oocyte maturation-inducing activity in the spotted flounder, Verasper variegatus, we have incubated post-vitellogenic oocytes (0.82­0.95mm in diameters) with radiolabeled pregnenolone and $17\alpha-hydroxyprogesterone$. The resulting metabolites were analyzed by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The two main metabolites (progestogens) found in both incubations co-migrated with $17\alpha-hydroxy$, $20\alpha-dihydroprogesterone$ $(17\alpha, 20\alpha OHP)$ and $17\alpha-hydroxy,\;$20\beta-dihydroprogesterone$ (17 a20{30HP). Additional chromatography by HPLC and TLC confirmed the presence of radioactive $17\alpha, 20\alpha OHP$ and a large amount of unknown metabolite. The present study did not reveal in vitro formation of $l7\alpha 20\beta OHP$. Although 1$l7\alpha 20\beta OHP$ was found in a small amount, the synthesis of this steroid suggests that it may play a role in regulating the oocyte maturation process in the spotted flounder.

• Natural Product Sciences
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• v.2 no.2
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• pp.90-95
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• 1996

When reserpine-producing cell strains of Rauwolfia serpentina were transferred from the dark to the light irradiation, the production of reserpine was extremely enhanced whereas the cell growth was suppressed. In an incubation period of 20 days, the most effective culture condition for reserpine production was the combination of 8 days of dark culture and following 12 days of light culture. The time courses of both cell growth and reserpine production were measured in vitro in order to clarify the effect of wave length range of light on the biosynthesis of reserpine. Although the growth of cultured cells which had been incubated under continuous red, yellow, and green lights, respectively, was similar to that of the cultured cells subcultured in the dark. The cells cultured under red light irradiation produced less reserpine than dark-grown cultures. Both blue and near-ultraviolet light inhibited the growth of cultured cells. The production of reserpine was strikingly enhanced by blue light, but was strongly inhibited by near-ultraviolet light.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.673-677
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• 1998

A inhibitor acting on substrate proteolytic enzyme was isolated from culture broth of Streptomyces sp. SK-862, which had been isolated from soil in Wonju City, by using the colloidal agar medium. The optimum culture temperature and initial pH for the production of the protease inhibitor was 28$^{\circ}C$ and pH 8.5, respectively. The optimum culture medium was composed of 1.5% glucose, 0.5% peptone, 0.1% K2PHO4, 0.05% CaCO3 and initial pH 8.5. The inhibitor production was maximum when the strain was incubated in shaking incubator at 70 strokes for 60 hours.

• Plant Resources
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• v.8 no.3
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• pp.175-180
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• 2005

Thin sections of cellulose fibers were incubated with an endo- and an exoglucanase labeled with gold particles of differing sizes. The hydrolytic sites were then visualized under transmission electron microscopy (TEM). The potential interaction between the ${\beta}$-1, 4-glucan substrates and the endo- and the exoglucanases was investigated using cellulosic and lignocellulosic substrates. The simultaneous visualization was very successful in distinguishing preferred substrates for each cellulase in lignocellulosic substrates. When plant lignocellulose was preincubated with endocellulase, density of the gold labeling greatly increased suggesting that preliminary exposure of lignocellulosic material to endocellulase may have enhanced the accessibility of the substrate to endocellulase and exocellulase. This result provided a plausible explanation for the observed endo/exo cellulase co-hydrolysis.

• IMMUNE NETWORK
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• v.14 no.6
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• pp.328-332
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• 2014

Dexamethasone (Dex) was shown to inhibit the differentiation, maturation, and antigen-presenting function of dendritic cells (DC) when added during DC generation or maturation stages. Here, we examined the direct effects of Dex on MHC-restricted antigen processing. Macrophages were incubated with microencapsulated ovalbumin (OVA) in the presence of different concentrations of Dex for 2 h, and the efficacy of OVA peptide presentation was evaluated using OVA-specific CD8 and CD4 T cells. Dex inhibited both class I- and class II-restricted presentation of OVA to T cells; this inhibitory effect on antigen presentation was much more potent in immature macrophages than in mature macrophages. The presentation of the exogenously added OVA peptide SIINFEKL was not blocked by Dex. In addition, short-term treatment of macrophages with Dex had no discernible effects on the phagocytic activity, total expression levels of MHC molecules or co-stimulatory molecules. These results demonstrate that Dex inhibits intracellular processing events of phagocytosed antigens in macrophages.

• Korean Journal of Animal Reproduction
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• v.16 no.3
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• pp.239-246
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• 1992

Capacitated and acrosome~reacted spermatozoa were microinjected into the perivitelline space of bovine oocytes matured in vitro. Oocytes obtained from the ovaries of slaughtered heifers and cows were cultured in vitro in the TCM-199 supplemented with 20% FCS for 24 hr at 39$^{\circ}C$ under an atmosphere of 5% CO$_2$ 8% O$_2$. Fresh or frozen spermatozoa were incubated for 2 hr at 39°C under an atmos-phere of 5% CO$_2$, 8% O$_2$ in Ham's F-lO medium containing 0.75% BSA for capacitation, and kept for 30 min in culture medium containing 12 mM of dbcGMP and lOmM of immidazol for acrosome resction. One motile spermatozoon was injected into the perivitelline space of each oocyte. The 2nd polar body and the pronuclei were observed in 9.5% and 5.4% of oocytes, respectively. The rate of cleavage of oocyte over 2-cell stage was 4.1%(10 of 242), These results indicate that the microinjection may be a useful technique to study sperm-oocyte interaction.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.212-218
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• 1995

A human hepatoma cell line, hep G2, was used to investigate the mechanism of serum cholesterol reduction by ginseng total saponin, ginsenoside-$Rb_1$, - $Rb_2$, and non-saponin fraction (ether extraction). Hep G2 cells were incubated in 10 $\mu\textrm{g}$/ml of cholesterol containing serum free-RPMl1640 medium with various concentration of ginseng components. The amounts of cholesterol in Hep G2 cells were decreased to maximum 51% in total saponin or two ginsenoside-treated groups while there was 137% increase in cholesterol level of control group as compared with that of normal group. Nonsaponin groups did not show the same effect. In order to elucidate the observed changes in the amount of cholesterol, the activity of amyl CoA : cholesterol acyltransferase (ACAT) in groups showing remarkable reduction in cholesterol amount, i.e., total saponin 10-6%, ginsenoside-$Rb_1$ $10^{-4}$%, ginsenoside-$Rb_2$, $10^{-4}$%, and non-saponin fraction $10^{-4}$%, was assayed using [1-$^{-14}C$%]oleic acid as enzyme substrate. The activity of ACAT was increased in all groups tested as compared with that of control group except for non-saponin group cultured in water soluble cholesterol containing medium. The serum cholesterol lowering effects of ginseng components can partially be attributed to the increased hepatocellular ACAT activity.