• 대한수의학회지
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• 제46권4호
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• pp.315-322
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• 2006

Ethanol abuse is associated with liver injury, neurotoxicity, modulation of immune responses, and increased risk for cancer, whereas moderate ethanol consumption exerts protective effects against liver injury. However, the underlying signal transduction mechanisms of insulin-like growth factors (IGFs) which play an important regulatory role in various metabolism mechanisms are not well understood. We investigated the effects of ethanol-induced p42/44 activity on IGF-I secretion, IGF-I receptor and IGFBP-1 secretion using radioimmunoassay and western blotting in primary cultured rat hepatocytes. The p42/44 activity, IGF-I secretion and IGF-I receptor activity significantly accelerated compared to control at 10 and 30 min after 200 mM ethanol treatment, but then it became suppressed at 180 min. In contrast, IGFBP-1 secretion was inhibited compared to control at 30 min after 200 mM ethanol treatment, but increased at 180 min. The IGF-I secretion, IGF-I receptor and p42/44 activity at 30 min after 200 mM ethanol treatment accelerated with increasing ethanol concentration but IGFBP-1 secretion inhibited (p<0.05). The increased IGF-I secretion, inhibited IGFBP-1 secretion and IGF-IR activity by ethanol-induced temporal p42/44 activity at 30 min after ethanol treatment was blocked by treatment with PD98059. Alcohol dehydrogenase (ADH) inhibitor, 4-methylpyramazole blocked the changes of IGF-I secretion, IGFBP-1 secretion, and IGF-IR activity by ethanol-induced p42/44 activity at 30 and 180 min. Taken together, these results suggest that ethanol is involved in the modulation of IGF-I and IGFBP-1 secretion and IGF-IR activity by p42/44 activity in primary cultured rat hepatocytes. In addition, changing of p42/44 activity by ethanol was caused with ADH.

• International Journal of Oral Biology
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• 제30권1호
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• pp.9-15
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• 2005

Recently, we reported that high extracellular calcium increased receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) expression via p44/42 mitogen-activated protein kinase (p44/42 MAPK) activation in mouse osteoblasts. However, the mechanism for p44/42 MAPK activation by high extracellular calcium is unclear. In this study, we examined the role of intracellular calcium increase in high extracellular calcium-induced RANKL induction and p44/42 MAPK activation. Primary cultured mouse calvarial osteoblasts were used. RANKL expression was highly induced by 10 mM calcium treatment. Ionomycin, a calcium ionophore, also increased RANKL expression and activated p44/42 MAPK. U0126, an inhibitor of MEK1/2, an upstream activator of p44/42 MAPK, blocked the RANKL induction by both high extracellular calcium and ionomycin. High extracellular calcium increased the phosphorylation of proline-rich tyrosine kinase 2 (Pyk2), one of the known upstream regulators of p44/42 MAPK activation. Bisindolylmaleimide, an inhibitor of protein kinase C, did not block RANKL induction and p44/42 MAPK activation induced by high extracellular calcium. 2-Aminoethoxydiphenyl borate, an inhibitor of inositol 1,4,5-trisphosphate (IP3) receptor, blocked the RANKL induction by high extracellular calcium. It also partially suppressed the activation of Pyk2 and p44/42 MAPK. Cyclosporin A, an inhibitor of calcineurin, also inhibited high calcium-induced RANKL expression in dose dependent manner. However, cyclosporin A did not affect the activation of Pyk2 and p44/42 MAPK by high extracellular calcium treatment. These results suggest that 1) the increase in intracellular calcium via IP3-mediated calcium release is necessary for RANKL induction by high extracellular calcium treatment, 2) Pyk2 activation, but not protein kinase C, following the increase in intracellular calcium might be involved in p44/42 MAPK activation, and 3) calcineurin-NFAT activation by the increase in intracellular calcium is involved in RANKL induction by high extracellular calcium treatment.

• 한국임상수의학회지
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• 제25권5호
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• pp.355-358
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• 2008

본 연구는 trophic factor supplementation (TFS)이 cold ischemic storage와 rewarming 동안에 신장 세포의 생존에 미치는 효과를 알아보기 위해 실시했다. p44/42와 p38 mitogen activated protein kinases (MAPK) 활성이 TFS에 의해 영향을 받는지를 Western blot을 통해 알아보았다. Apoptotic changes를 알아보기 위해 4',6'-diamino-2-phenylindole (DAPI) 염색을 실시했다. 세포생존도를 알아보기 위해 live assay를 실시하였다. 그 결과, TFS는 cold ischemic storage와 rewarming 동안 증가된 44/42와 p38 MAPK activity를 유의성 있게 감소시켰다 (p<0.05). 또한, cold ischemic storage와 rewarming에 의한 apoptotic cell 수가 TFS에 의해 감소함을 관찰했다. 마지막으로 TFS는 유의성 있게 세포 생존도를 증가시켰다 (p<0.05). 따라서, TFS는 p44/42와 p38 MAPK 활성을 감소시키고 apoptotic change를 억제함으로써 cold ischemia와 rewarming injury로부터 신장 세포를 보호하는 것으로 생각된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2002년도 창립10주년기념 및 국립독성연구원 의약품동등성평가부서 신설기념 국재학술대회:생물학적 동등성과 의약품 개발 전략을 위한 국제심포지움
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• pp.238-238
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• 2002

We studied whether kinase pathways are involved in TCDD-induced gene expression by treating specific kinase inhibitors ncluding MEK1 inhibitor PD98059, p38 inhibitor SB202190, PI-3 kinase inhibitor Wortmannin or LY294002 or protein tyrosine kinase inhibitor Genestein and then tested the effects of individual inhibitors on TCDD-induced gene expression of cytochromelAl gene (CYPlAl). Our results show that PD98059, MEK-1 inhibitor reduces dioxin-inducible transcription of CYPlAl. p44/p42MAPK, that is phosphorylated by Mek-1, are phosphorlylated by treatment of TCDD, peaking at lnM, 30min treatments. Overexpressions of p44/p42 MAPK dominant negative mutants suppress dioxin dependent transcription of DRE-driven reporter gene in a dose-dependent manner. Our results demonstrate that p44/p42 MAPK is essential for transcriptional activity of AHR/ARNT heterodimer. We found that PD98059 dose-dependently blocks TCDD-induced DRE binding of the AHR/ARNT heterodimer, thereby it reduces TCDD-induced gene expression. Therefore, our results indicate that Mek-1/p44/p42 MAPK pathway is involved in TCDD-induced gene expression, [This study was supported by a grant from Korean Research Foundation Grant (X01529)to H. Park]

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.788-795
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• 2009

Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis under various physiological and pathological conditions. We found that the VEGF isoforms VEGF120, VEGF164, and VEGF188 were expressed in the bovine mammary gland and bovine mammary epithelial cells (bMECs). Expression of VEGF in the mammary gland was significantly higher during the lactation period than during the dry period. Although dexamethasone or prolactin alone had little effect on the expression of VEGF, that in dexamethasone-treated cells was significantly induced after additional treatment with prolactin. Furthermore, the VEGF expression induced by the combination of dexamethasone and prolactin was reduced by PD98059 in a dose-dependent manner. This combination also stimulated the phosphorylation of p44/p42 MAP kinase in these cells. These results strongly suggest that the combination of dexamethasone and prolactin stimulates VEGF expression in bMECs via p44/p42 MAP kinase.

• 한국동물위생학회지
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• 제31권4호
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• pp.457-463
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• 2008

The sex steroid hormone estradiol-$17{\beta}(E_2)$ mediate their biological effects on development, differentiation and maintenance of reproductive tract and other target tissue through gene regulation by nuclear steroid receptors. Although the importance of $E_2$ in many physiological process has been reported, but little is known about the effects of $E_2$ on primary cultured chicken hepatocyte. therefore, in the present study, we have examined the effect of $E_2$ on cell proliferation and it's related signal cascades. $E_2$ increase $[^3H]$-thymidine incorporation in time-(${\leq}8hr$) and dose-($10^{-10}M$)dependent manner and treatment of $E_2$ increased the phosphorylation of p44/43 MAPKs(p44/42 mitogen-activated protein kinase) and JNK(c-Jun N-terminal kinase) in a time dependent manner. In addition, PD98059(p44/42 blocker, $10^{-5}M$), SP600125(JNK blocker, $10^{-6}M$) blocked the estrogen-induced increase in $[^3H]$-thymidine incorporation. In conclusion, $E_2$ stimulates the proliferation of primary cultured chicken hepatocytes and this action is mediated by p44/42 MAPKs and JNK signal transduction pathway.

• Radiation Oncology Journal
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• 제6권2호
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• pp.155-161
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• 1988

The usefulness of hypertermia for cancer therapy have well been established. The purpose of the present investigation was to ascess the effect of step-up $(42^{\circ}{\rightarrow}44^{\circ}C$ sequence) and step-down $(44^{\circ}{\rightarrow}42^{\circ}C$ sequence) heating on the skin of the hind foot of the mouse. Hyperthermic treatments were given by immersion the hind foot of the mouse in circulating water baths. Skin response was studied by the leg reaction, which was scored according to a numerical scoring system proposed by Urano et al (1980). The results were as follows 1. The skin damage of $44^{\circ}C$ control group was more severe than $42^{\circ}C$ control group (P<0.05), except for 15 min. heating group. 2. The Skin damage of step-down group was more severe than step-up group (P<0.05). 3. The skin damage of $44^{\circ}C$ control group was more severe than step-up group when there is no difference in $44^{\circ}C$ heating time of step-up group from $44^{\circ}C$ control group (P<0.05). 4. In step-down group, the skin damage was more severe than $44^{\circ}C$ control group after preheating 45 min at $44^{\circ}C$ (P<0.05). Therefore, the above findings suggest the normal tissue damage by step-up heating was correlated with heating time of post step-up. The dropping of heating temperature in late phase had more severe damage of the skin than that in early phase during hyperthermia, and so contineous control of satisfactory temperature should be considered as the one of the most important factor for prognosis, complications of clinical hyperthermia

• Journal of Animal Science and Technology
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• 제66권5호
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• pp.905-919
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• 2024

Porcine oocytes undergo in vitro maturation (IVM) for 42-44 h. During this period, most oocytes proceed to metaphase and then to pro-metaphase if the nucleus has sufficiently matured. Forty-four hours is sufficient for oocyte nuclear maturation but not for full maturation of the oocyte cytoplasm. This study investigated the influences of extension of the IVM duration with rapamycin treatment on molecular maturation factors. The phospho-p44/42 mitogen-activated protein kinase (MAPK) level was enhanced in comparison with the total p44/42 MAPK level after 52 h of IVM. Oocytes were treated with and without 10 µM rapamycin (10 R and 0 R, respectively) and examined after 52 h of IVM, whereas control oocytes were examined after 44 h of IVM. Phospho-p44/42 MAPK activity was upregulated the 10 R and 0 R oocytes than in control oocytes. The expression levels of maternal genes were highest in 10 R oocytes and were higher in 0 R oocytes than in control oocytes. Reactive oxygen species (ROS) activity was dramatically increased in 0 R oocytes but was similar in 10 R and control oocytes. The 10 R group exhibited an increased embryo development rate, a higher total cell number per blastocyst, and decreased DNA fragmentation. The mRNA level of development-related (POU5F1 and NANOG) mRNA, oocyte-apoptotic (BCL2L1) genes were highest in 10 R blastocysts. These results suggest that prolonged IVM duration with rapamycin treatment represses ROS production and increases expression of molecular maturation factors. Therefore, this is a good strategy to enhance the developmental capacity in porcine oocytes.

• 한국수정란이식학회지
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• 제21권2호
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• pp.129-135
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• 2006

본 연구는 돼지 체외 수정란의 생산에 있어서 체외성숙 시간이 핵성숙, 다정자 침입율 및 배 발생과 배반포의 부화율 배반포의 부화에 미치는 효과를 검토하였다. 돼지 난포란의 핵성숙율이 체외성숙 36, 38, 40, 42 및 44 시간째에 각각 68.0, 78.0, 79.5, 73.8 및 81.8%로서 각 군간에 유사한 경향이었으며, 체외 수정 후 다정자 침입율도 각각 48.7, 36.0, 44.4, 38.9 및 31.8%로서 차이가 없었다. 체외 성숙 시간에 따른 2세포기 발달율은 체외 성숙 36시간군이 77.3%로서 가장 높았고, 체외 성숙 40 및 44 시간의 70.6 및 70.3%와는 유의차가 인정되었다(p<0.05). 배반포 발달율은 38시간군의 23.1%가 체외 성숙 44 시간군의 15.6%보다 유의하게 높았다(p<0.05). 따라서 돼지 난포란의 44시간 체외 성숙이 배 발생에 비효과적이었다.

• 한국어류학회지
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• 제7권1호
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• pp.79-83
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• 1995

제주도 근해산 놀래기과 어류들에서 암 수간 heteromorphic한 성염색체는 발견할 수 없었고 황놀래기, 놀래기, 용치놀래기, 어렝놀래기의 염색체수(핵형)은 각각 42(4M+24SM+14ST, A), 48(2M+2SM+44ST, A), 48(2M+46ST, A), 42(4M +24SM+14ST, A)로 나타났으며 황놀래기, 어렝놀래기인 경우 가장 큰 2개의 subtelocentrics에 satellite가 존재하였다.