• Journal of Life Science
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• v.24 no.10
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• pp.1137-1143
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• 2014

Doxorubicin is a general chemotherapy drug widely used for a number of cancers. However, the correlation between endogenous nitric oxide ($NO^{\bullet}$) levels and chemoresistance to doxorubicin remains unclear. In this study, we investigated the effect of endogenous $NO^{\bullet}$ on the anticancer activity of doxorubicin in human colon cancer cell lines HCT116 and HT29 with different p53 status. The cells were treated with either doxorubicin alone or in combination with the $NO^{\bullet}$ synthase (NOS) inhibitor $N^G$-monomethyl-L-arginine (NMA). Doxorubicin differentially inhibited the growth of both the HCT116 (p53-WT) and HT29 (p53-MUT) cells, which was mitigated by cotreatment with NMA. Further studies revealed that inhibition of endogenous $NO^{\bullet}$ mitigated doxorubicin-induced apoptosis in the HCT116 and HT29 cells, as evidenced by apoptotic DNA fragmentation and the sub-G1 peak of apoptotic markers. Apoptosis was delayed in the HT29 cells, and its magnitude was greatly reduced, underscoring the importance of the modulation of p53 in the response. RT-PCR analysis revealed that doxorubicin down-regulated levels of inhibitors of the apoptosis family (cellular IAP-1 and-2). Collectively, these data show that induction of apoptosis by doxorubicin in human colon cancer cells is possibly related to modulation of endogenous $NO^{\bullet}$, the expression of the IAP family of genes, and the status of p53. The underlying mechanisms may represent potential targets for adjuvant strategies to improve the efficacy of chemotherapy for colon cancer.

• Journal of Embryo Transfer
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• v.26 no.4
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• pp.277-282
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• 2011

The present research was carried out to evaluate the possibility of increasing female offspring production ratios using artificial insemination buffer (AIB) before artificial insemination (AI). In this experiment, we optimized AIB composition, made an AIB gun and analyze factors affecting AI non-return rate after AIB treatment. The AIB was made with the base of Tris-buffer supplemented with L-arginine and several other chemicals that might reduce the motility of male sperm compared to the female counterpart, therefore, increasing the possibility of fertilization by female sperm. AIB must be deposited into $2^{nd}$ to $4^{th}$ cervix by AIB gun. After 15 min of AIB deposition, frozen semen was deposited into the same place. A total of 348 cattle were inseminated with AIB insemination, and there were no significant differences between AIB and traditional AI non-return rates (56.8% vs. 55.7%). The AI non-return rate in AIB group, however, differed significantly among 7 Hanwoo farms. The parturition numbers ($1^{st}$ to $7^{th}$) of cows did not affect AIB AI rate. The proportion of AIB AI success rates was significantly higher in Hanwoo cows than in dairy cows (61.0% vs. 48.7%), but the average AI success rate did not differ significantly between AIB and conventional AI (56.8% vs. 55.7%). The female offspring production rate in $2^{nd}$ to $4^{th}$ cervix deposition place was significantly higher than that in the uterus body (77.7% vs. 59.6%, p<0.05). The injection volume of AIB in 5 and 10 ml was significantly higher than that in 2 ml (77.7%, 78.7% vs. 51.8%, p<0.05), but there were no differences in AIB injection volume between 5 and 10 ml. The best exposure time of AIB in the cervix was 10 to 15 min rather than 5 min (79.2%, 77.2% vs. 52.6%, p<0.05). AIB therefore needs to have an exposure time of at least over 10 min for a higher production rate of female offspring. In conclusion, AIB could be used in AI industry to increase the female offspring ratio and AIB AI can increase the AI success rate.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.181-190
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• 1994

Endothelium-derived relaxing factor (EDRF) activates guanylate cyclase which mediates the formation of cGMP from GTP in vascular smooth muscle. It is well known that endothelium-dependent relaxation is impaired in spontaneously hypertensive rats (SHR). However, it is still unknown whether the impaired endothelium-dependent relaxation in SHR results from the reduced release of EDRF or from the decrease of vascular response to EDRF. We investigated the effects of cGMP on the contractility and Ca movement in the aorta of SHR and Wistar-Kyoto rats (WKY). The amplitude of the endothelium-dependent relaxation to actylcholine (ACh) was significantly less in SHR than in WKY. L-arginine $(10^{-3}M)$ did not increase endothelium-dependent relaxation in both strains. Sodium nitroprusside (SNP), an activator of guanylate cyclase, relaxed the 40 mM $K^+-induced$ contraction in a dose-dependent manner $(10^{-10}{\sim}10^{-6}\;M)$ in the endothelium-rubbed aortic strips of both strains. However, there was no significant difference in these relaxations between WKY and SHR. 8-bromo-cyclic guanosine monophosphate (8-Br-cGMP), a cell membrane-permeable derivative of cGMP relaxed the 40 mM $K^+-induced$ contraction in a dose-dependent manner $(10^{-6}{\sim}10^{-4}\;M)$ in the endothelium-rubbed aortic strips of both strains. Also norepinephrine $(10^{-6}\;M)-induced$ contractions in normal and Ca-free Tyrode's solution were suppressed by the pretreatment with 8-Br-cGMP $(10^{-4}\;M)$ in either strain. However, the amplitudes of suppression induced by 8-Br-cGMP were greater in SHR than that in WKY. Basal $^{45}Ca$ uptake and 40mM $K^+-stimulated\;^{45}Ca$ uptake were not suppressed by pretreatment with 8-Br-cGMP $(10^{-4}\;M)$ in single aortic smooth muscle cells of both SHR and WKY. From the above results, it is suggested that cGMP decreases Ca sensitivity in vascular smooth muscle cells and that the impaired endothelium-dependent relaxation in the aortic strips of SHR is not the result of a reduced vascular response to EDRF.

• The Journal of Internal Korean Medicine
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• v.27 no.1
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• pp.276-287
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• 2006

Background & Objective : The herbal medicine Sojukgunbihwan granule has been used for the treatment of functional dyspepsia, generally categorized as a gastric dysmotility disease. However, its mechanisms are not yet well known. Therefore, the effects of Sojukgunbihwan granules on gastric motility in rats was investigated. Methods : The myoelectrical activity of the gastric smooth muscle was recorded by a bipolar electrode placed at the gastric antrum of rats. The contractile waves were measured for 30 minutes before and after intragastric administration of each solution(normal saline, Pyungwisan 40mg/kg, Sojukgunbihwan granules 60mg/kg) and expressed as the motility index. Gastric emptying was measured by the number of glass beads expelled from the stomach(containing one hundred 1mm glass beads) within an hour after glass beads and test drugs(normal saline, Pyungwisan 40mg/kg, Pyungwisan 120mg/kg, Sojukgunbihwan granules 60mg/kg, Sojukgunbihwan granules 180mg/kg) were administered. In another series of experiments to evaluate the mechanisms of Sojukgunbihwan granules under delayed conditions, the rats were treated with atropine sulfate(1 mg/kg, s.c.), cisplatin(10mg/kg, i.p.), and NAME($N^G$-nitro-L-arginine methyl ester, 75mg/kg, s.c.) respectively. Results : Intragastric administration of Sojukgunbihwan granules increased the myoelectrical activity significantly, gastric motility index rose 25%, and gastric emptying of glass beads was significantly enhanced over a period of 60minutes. Under the delayed gastric emptying induced by atropine sulfate, cisplatin, and NAME, Sojukgunbihwan granules aggravated gastric emptying in the atropine sulfate($5.71{\pm}3.45\;vs\;3.71{\pm}4.42$) and cisplatin($13.86{\pm}3.53\;vs\;5.14{\pm}5.05$, p<0.01) treated groups, but enhanced gastric emptying in the NAME treated group($5.00{\pm}3.21\;vs\;11.71{\pm}5.65$, p<0.05). Conclusions : Results suggest that Sojukgunbihwan granules stimulate gastric motility through cholinergic and 5-hydroxytryptamine 3 receptors. Results are indicative of Sojukgunbihwan as an especially effective remedy in dysmotility-like functional dyspepsia with impaired reservoir functions such as gastric adaptive relaxation.

• The Journal of Internal Korean Medicine
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• v.21 no.3
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• pp.467-475
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• 2000

The water extracts of Jagamcho-tang has been used for treatment of arrhythmia and palpitation in oriental traditional medicine. Brain is provided with blood flow by heart. Jagamcho-tang has been studied on ischemia and infarction in heart. However, little is known about the mechanism by which the water extracts of Jagamcho-tang rescues brain cells from ischemic damages. To elucidate the protective mechanism on ischemic induced cytotoxicity, the effects of Jagamcho-tang on ischemia induced cytotoxicity and generation of nitric oxide(NO) are investigated in C6 glioma cells. Jagamcho-tang induce NO in a dose dependent manner up to 2.5mg/ml in C6 glioma cells. The pretreatment of Jagamcho-tang protect sodium nitroprusside(SNP) (2mM) induced cytotoxicity. This effect of Jagamcho-tang is mimicked by treatment by pretreatment of SNP($100{\mu}M$), an exogenous NO donor. NG-monomethyl-L-arginine($N^{G}MMA$), a specific inhibitor of nitric oxide synthase (NOS), significantly blocks the protective effects of Jagamcho-tang on cell toxicity by ischemia. In addition, lipopolysaccharide(LPS) and phorhol 12 myristate 13-acetate(PMA) treatment for 72h in C6 glial cells markedly induce NO, but treatment of the cells with the water extracts of Jagamcho-tang decrease nitrite formation in a dose dependent manner. In addition, LPS and PMA treatment for 72h induce severe cell death and LDH release into medium in C6 glial cells. However treatment of the cells with the water extracts of Jagamcho-tang dose not induce significant changes compare to control cells. Furthermore, the protective effects of the water extracts of Jagamcho-tang is mimicked by treatment of $N^{G}MMA$. Taken together, I suggest that the protective effects of the water extracts of Jagamcho-tang against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.771-774
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• 2008

Familial hypokalemic periodic paralysis (hypoPP) is a rare inherited channelopathy that often presents with episodic weakness accompanied by hypokalemia. Thus far, mutations in the gene encoding two ion channels (CACNL1A3, L-type calcium channel alpha-1 subunit and SCN4A, a sodium channel type IV alpha subunit) have been identified. Several cases of familial hypoPP in children have been reported in Koreans, but there are only a few cases with identified mutations. We report a 12-year-old boy and his affected mother with hypoPP who has a heterozygous G to A substitution at codon 1239 in exon 30 of the CACNL1A3 gene that causes a change from arginine to histidine (Arg1239His, CACNL1A3). This mutation is common among Caucasians; however, it has not yet been reported in Koreans. The patients were treated with oral acetazolamide and potassium replacement and were instructed to avoid precipitating factors. After the medication and lifestyle modification, the paralytic attacks significantly decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.215-223
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• 2009

This study was conducted to investigate the effect of diets supplemented with different levels (0, 2.5, 5.0, and 7.5%) of yuza (Citrus junas Sieb ex Tanaka) on nutritional composition of olive flounder. Four groups of fish (242.2$\pm$14.2 g) were fed to apparent satiation twice daily for 4 months. There were no significant differences in proximate composition among the treatment groups (P<0.05). Vitamin C content in flounder muscle was higher in the yuza-added groups than in the control group, and the content among the treatment groups increased as amount of yuza added to diets increased (P<0.05). Of the eight organic acids in flounder muscle, lactic acid was predominant, followed by oxalic acid, succinic-acid, tartaric acid, and acetic acid. Flounders fed 2.5% yuza diet had the highest lactic acid content of all treatments. Four sugars were found in all groups and glucose was the major sugar. Glucose and ribose were detected as the highest sugars in the 2.5% treatment, while maltose and galactose were the dominant sugars in the 5.0% treatment. The abundant fatty acids in fed flounders were 22:6n-3 (DHA), 16:0, and l8:1n-9, which were composed of over 60% of total fatty acids. The control and the 7.5% treatment group had higher 22:6n-3 (DHA) content than the other groups. Major amino acids in samples were glutamic acid, aspartic acid, lysine, leucine, valine, arginine, and alanine. The 2.5% yuza treatment had the highest content of total amino acids and essential amino acids. There were little differences in the free amino acid compositions among the treatments. However, taurine was the predominant amino acid and made up over 47% of total free amino acids. The 2.5% added yuza group contained higher amount of sweet amino acids such as alanine, serine, proline, glycine than the other groups. The addition of yuza to diet of olive flounder had no or little effect on the nutritional components of olive flounder except for vitamin C. However, the 2.5% yuza added group had the highest nutritional values of the treatment groups.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.3
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• pp.177-183
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• 2010

Tetrahydrobiopterin (BH4), an essential cofactor for nitric oxide synthase (NOS) activity, is known to play important roles in modulating both NO and superoxide production during vascular diseases such as atherosclerosis. However, the role of BH4 in functions of vascular smooth muscle cells is not fully known. In this study, we tested the effects of BH4 and dihydrobiopterin (BH2), a BH4 precursor, on migration and proliferation in response to platelet-derived growth factor-BB (PDGF-BB) in rat aortic smooth muscle cells (RASMCs). Cell migration and proliferation were measured using a Boyden chamber and a 5-bromo-2'-deoxyuridine incorporation assay, respectively, and these results were confirmed with an ex vivo aortic sprout assay. Cell viability was examined by 2,3-bis [2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide assays. BH4 and BH2 decreased PDGF-BBinduced cell migration and proliferation in a dose-dependent manner. The inhibition of cell migration and proliferation by BH4 and BH2 was not affected by pretreatment with $N^G$-nitro-L-arginine methyl ester, a NOS inhibitor. Moreover, the sprout outgrowth formation of aortic rings induced by PDGF-BB was inhibited by BH4 and BH2. Cell viability was not inhibited by BH4 and BH2 treatment. The present results suggest that BH4 and BH2 may inhibit PDGF-stimulated RASMC migration and proliferation via the NOS-independent pathway. Therefore, BH4 and its derivative could be useful for the development of a candidate molecule with an NO-independent anti-atherosclerotic function.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.297-303
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• 2012

This study was designed to elucidate high $K^+$-induced relaxation in the human gastric fundus. Circular smooth muscle from the human gastric fundus greater curvature showed stretch-dependent high $K^+$ (50 mM)-induced contractions. However, longitudinal smooth muscle produced stretch-dependent high $K^+$-induced relaxation. We investigated several relaxation mechanisms to understand the reason for the discrepancy. Protein kinase inhibitors such as KT 5823 (1 ${\mu}M$) and KT 5720 (1 ${\mu}M$) which block protein kinases (PKG and PKA) had no effect on high $K^+$-induced relaxation. $K^+$ channel blockers except 4-aminopyridine (4-AP), a voltage-dependent $K^+$ channel ($K_V$) blocker, did not affect high $K^+$ -induced relaxation. However, N(G)-nitro-L-arginine and 1H-(1,2,4)oxadiazolo (4,3-A)quinoxalin-1-one, an inhibitors of soluble guanylate cyclase (sGC) and 4-AP inhibited relaxation and reversed relaxation to contraction. High $K^+$-induced relaxation of the human gastric fundus was observed only in the longitudinal muscles from the greater curvature. These data suggest that the longitudinal muscle of the human gastric fundus greater curvature produced high $K^+$-induced relaxation that was activated by the nitric oxide/sGC pathway through a $K_V$ channel-dependent mechanism.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.2
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• pp.119-128
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• 2013

A protease inhibitor was fractionated from fish eggs using methods based on protein solubility. Fractionation efficiency was evaluated with regard to percent recovery and total inhibitory activity (U). The fractionation of protease inhibitor (PI) from egg extracts of skipjack tuna (ST, Katsuwonus pelamis), yellowfin tuna (YT, Thunnus albacores), and Alaska pollock (AP, Theragra chalcogramma) was performed by precipitation with cold acetone or ammonium sulfate (AS). Fractions exhibiting the strongest inhibitory activity contained 20-40% (v/v) cold acetone or 40-60% saturated AS fractions. AS fractionation was more effective in isolating PI than was precipitation with acetone. The total inhibitory activity and percent recovery of fraction obtained with AS 40-60% toward trypsin and $N{\alpha}$-benzoyl-L-arginine-p-nitroanilide (BAPNA) were 4,976 U and 24.2% for ST, 3,331 U and 38.1% for YT, and 4,750 U and 43.8% for AP, respectively. In comparisons against six commercial proteases, 40-80% AS fractions, made by combining the 40-60% and 60-80% AS fractions from fish egg extract, exhibited the strongest inhibition of trypsin when using a casein substrate. These results suggest that fish eggs act as serine protease inhibitors and may be useful for protease inhibition in foodstuffs.