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        검색결과 12

        2.
        2016.06 구독 인증기관 무료, 개인회원 유료
        Kisspeptin (Kiss) and its cognate receptor, kisspeptin receptor (KissR; G protein coupled receptor 54, GPR54), have recently been recognized as potent regulators of reproduction in teleosts. Additionally, leptin plays an important role in energy homeostasis and reproductive function in teleosts. The purpose of this study was to examine differences in the concentration of the hormones of the Kiss/KissR system and leptin and the expression of their underlying genes, all of which are involved in the sexual maturation of female goldfish, Carassius auratus, following treatment with Kiss. The expression levels of KissR increased after the Kiss injection. Furthermore, the peptide hormone leptin also increased after the injection (in vivo and in vitro). Additionally, the expression of GnRH and GTHs (GTHα, FSHβ, and LHβ) increased in the brain and pituitary (in vitro and in vitro). These results support the hypothesis that Kiss plays important roles in the direct regulation of the hypothalamus-pituitary-gonad axis and leptin in goldfish. Therefore, we suggest that Kiss system gene expression is correlated with energy balance and reproduction.
        4,000원
        3.
        2013.06 구독 인증기관 무료, 개인회원 유료
        Leptin is one of the adipocytokines produced from adi- pose tissue but its functions in periodontal tissue have not previously been investigated. In our current study, we exa- mined the effects of leptin on the expression of interleukin (IL)-6 and IL-8 in periodontal ligament (PDL) cells and gingival fibroblasts. Leptin receptor expression was evalua- ted by RT-PCR and the production of cytokines was mea- sured by ELISA. The phosphorylation of Akt and Erk1/2 was assessed by western blotting. mRNA of long and short form leptin receptors were detected in both PDL cells and gingival fibroblasts. Leptin was found to increase the pro- duction of IL-6 and IL-8 in both of these cell types, an effect which was not blocked by polymyxin B, an inhibitor of lipopolysaccharide (LPS). Leptin did not alter the pro- duction of IL-6 and IL-8 induced by LPS in PDL cells but increased Akt and Erk1/2 phosphorylation in these cells. These results suggest that leptin acts as an inducer of IL-6 and IL-8 in PDL cells and gingival fibroblasts.
        4,000원
        4.
        2012.06 구독 인증기관·개인회원 무료
        The objective of this study was to investigate the effects of NEAA and leptin supplemented to in vitro culture medium on the developmental competence of porcine embryos after intracytoplasmic sperm injection (ICSI), and to modify the culture condition to improve the quality and the development of ICSI-derived porcine embryos in vitro. After ICSI, the putative zygotes were then cultured in PZM-3 medium with/without NEAA or leptin. The proportion of embryos that developed to the blastocyst stage significantly increased when 1% NEAA (24.62%) was added to the medium compared with 2% NEAA and no NEAA group (17.24% and 20.24%, respectively, p<0.05). The effect of different concentration of leptin (0, 10, 100, 500 ng/ml) was evaluated on the development of porcine ICSI embryos cultured in vitro. In case of blastocyst formation, 100 ng/ml group (27.05%) showed significantly higher rate than 10, 500 ng/ml, and control group (23.45%, 17.99%, and 19.68%, respectively, p<0.05). We also evaluated the effects of different NEAA and leptin treatment time on the development of porcine embryos after ICSI. Among groups of embryos cultured in the presence of NEAA or leptin for whole 7 days (D 1-7), first 4 days (D 1-4), the subsequent 3 days (D 5-7), both NEAA (27.13%, 21.17 %, and 17.56%, respectively, p<0.05) and leptin (25.60%, 20.61%, and 16.53%, respectively, p<0.05) showed that supplementation for whole 7 days significantly increased the blastocyst formation rate compared with the other groups of D1-4 and D5-7. We further evaluated the combination effect of 1% NEAA and 100 ng/ml leptin compared with the effect of each supplementation with 1% NEAA or 100 ng/ml leptin or no supplementation on development of embryos. For blastocyst formation, combination group of NEAA and leptin (24.78%) showed significantly higher rate than other three groups (18.37%, 20.44 %, and 13.27%, respectively, p<0.05). We further evaluated the expression of proapoptosis genes such as BAX and BAK and anti-apoptosis genes, BCL-XL and BCL-2 in blastocysts cultured in the presence of 100 ng/ml leptin. RT-PCR analysis revealed that leptin supplementation significantly decreased the expression of pro-apoptosis genes as well as increased the expression of anti-apoptosis genes. These results of present study demonstrate that NEAA and leptin could improve the in vitro development of ICSI- derived porcine embryos with optimal concentration of each reagent. Furthermore, the optimal culture condition could increase the quality of ICSI-derived embryos in vitro.
        5.
        2008.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study is to investigate the changes in concentrations of leptin and insulin in serum of Korean cattle (Hanwoo) with reproductive disorders and to examine the relationship among leptin, insulin, and body condition score (BCS). The concentration of leptin in serum of pregnant Hanwoo showed insignificant difference from that in serum of Hanwoo with reproductive disorder, such as repeat breeding, follicular cyst, corpus luteum cyst, ovarian atrophy, and feeble estrus (p>0.05). However, the concentrations of leptin and insulin in serum were changed with different BCS value. In emaciated Hanwoo (BCS ), they were significantly decreased compared to BCS (p<0.05). The leptin showed different genotypes with different BCS value. In BCS , C/T genotype was expressed (83.3%) more than C/C (16.7%) or T/T (0%) genotype, whereas C/C genotype was expressed (62.5%) more than C/T (25.0%) or T/T (12.5%) genotype in BCS . The insulin concentration in follicular fluid obtained from ovary with follicular cyst which has follicles having diameter of was significantly higher (p<0.05) than those in normal follicle fluid which has follicles having diameter of . These results showed that concentration of leptin and insulin in serum were related to BCS value and follicular size and suggest that the changes in concentration of leptin and/or insulin in serum could be a potent biomarker for diagnosis of bovine reproductive disorder.
        4,000원
        8.
        2005.06 구독 인증기관 무료, 개인회원 유료
        Leptin, the product of the obese gene, is a circulating hormone secreted primarily from adipocytes. Several results suggest that leptin is important mediators of bone metabolism. The present study was undertaken to determine the effects of leptin on anti-osteoclastogenesis using murine precursors cultured on Ca-P coated plates and on the production of osteoprotegerin (OPG) in osteoblastic cells. Additionally, this study examined the possible involvement of prostaglandin E₂(PGE₂)/вввB/protein kinase C (PKC)-mediated signals on the effect of leptin on anti-osteoclastogenesis to various culture systems of osteoclast precursors. Osteoclast generation was determined by counting tartrate-resistant acid phosphatase positive [TRAP (+)] multinucleated cells (MNCs). Osteoclastic activity was determined by measuring area of resorption pits formed by osteoclasts on Ca-P coated plate. The number of 1,25-dihydroxycholecalciferol 1.25[OH]₂D₃- or PGE₂-induced TRAP (+) MNCs in the mouse bone marrow cell culture decreased significantly after treatment with leptin. The number of receptor activator of NF-kB ligand (RANKL)-induced TRAP (+) MNCs in M-CSF dependent bone marrow macrophage (MDBM) cell or RAW264.7 cell culture decreased significantly with leptin treatment. Indomethacin inhibited osteoclast generation induced by 1.25[OH]₂D₃ and dexamethasone, however, no significant differences were found in the leptin treated group when compared to the corresponding indomethacin group. Phorbol 12-myristate 13-acetate (PMA), a PKC activator, inhibited osteoclast generation induced by 1.25[OH]₂D₃The number of TRAP (+) MNCs decreased significantly with treatment by PMA at concentrations of 0.01 and 0.1μM in culture. Leptin inhibited PMA-mediated osteoclast generation. Isoquinoline-5-sulfonic 2-methyl-1-piperazide dihydrochloride (H7) had no effect on osteoclast generation induced by 1.25[OH]₂D₃ Cell culture treatment with leptin resulted in no significant differences in osteoclast generation compared to the corresponding H7 group. Indomethacin showed no significant effect on TRAP (+) MNCs formation from the RAW264.7 cell line. PMA inhibited TRAP (+) MNCs formation induced by RANKL in the RAW264.7 cell culture. H7 had no effect on osteoclast generation from the RAW264.7 cell line. There was no difference compared with the corresponding control group after treatment with leptin. 1.25[OH]₂D₃- or PGE₂-induced osteoclastic activity decreased significantly with leptin treatment at a concentration of 100 ng/ml in mouse bone marrow cell culture. Indomethacin, PMA, and H7 significantly inhibited osteoclastic activity induced by 1.25[OH]₂D₃ in mouse bone marrow cell culture. No significant differences were found between the leptin treated group and the corresponding control group. The secretion of OPG, a substance known to inhibit osteoclast formation, was detected from the osteoblasts. Treatment by leptin resulted in significant increases in OPG secretion by osteoblastic cells. Taken these results, leptin may be an important regulatory cytokines within the bone marrow microenvironment.
        4,200원
        9.
        2006.06 KCI 등재 서비스 종료(열람 제한)
        Introduction : The obesity can be a serious problem that frequently induces a great deal of complications. Numerous methods have been applied to control obesity and one of them is aromatherapy. This study is a first attempt to verify the effect of the inhalation of essential oils on the obesity. This study was designed as the animal study, because the human study has many socio-psycho compounding variables. Methods : This study was designed to verify the effect of inhalation of essential oils on the body weight, feeding amount, food efficiency rate and serum leptin of SD rats. The research design is repeated measures over time, equivalent control group pretest-posttest experimental design. The subjects of this experiment were obese SD rats. They were allocated to one of four groups, the Fennel G., the Patchouli G., the Bergamot G. and control G. The experimental treatment was the inhalation of aromatherapy essential oils (Fennel, Patchouli, Bergamot). The experimental treatment was applied two times a day for 10 minutes each during 8 weeks. To evaluate the effect of inhalation of essential oils, the body weight, feeding amount and food efficiency rate was measured every week and serum leptin was measured before and after the experiment. The collected data was analyzed by repeated measures of ANOVA, Greenhouse-Geisser, ANOVA, Tukey, Kruskal Wallis test and χ²- test with SPSS program. Results : The results were as follows. The subjects of this study was 84 obese SD rats(40 males and 44 females). The means of age and body weight in obese SD rats were 30 weeks and 344.6g. The food efficiency rate was significantly lower in the Patchouli group and Fennel group than in Bergamot group and control group(P=.000). No significant group effects were found, but significant time effects were found for SD rat's body weight, feeding amount and serum leptin. Conclusions : In conclusion, these findings indicate that the inhalation of essential oils could be effective in lowering the food efficiency rate. 2)
        10.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        비만유전자 산물인 leptin은 비만뿐만 아니라 여성의 생식 생리와 관련이 있는 것으로 보이나, 아직 이러한 leptin이 난소에 직접적으로 작용하는지 정확하게 밝혀지지 않고 있다. 따라서 본 연구에서는 흰쥐 난소에서 leptin과 leptin 수용체의 발현을 면역조직화학방법으로 확인하고 발정주기에 따른 leptin과 leptin 수용체의 발현 양상을 RT-PCR 방법으로 조사하고자 하였다. 면역조직화학적 염색방법 결과 흰쥐 난소내에서 leptin은 협
        11.
        2001.06 서비스 종료(열람 제한)
        1. Leptin itself was not expressed in mouse uterine tissues. 2. Leptin receptors were not expressed in nonpregnant and little expressed in 3.5 day of pregnant uterine tissues. However, there was a signal in 4.5 and 5.5 day of tissues. 3. The expression level of leptin receptor variants in the implantation sites at around the time of initial embryo attachment (day 4.5 of pregnancy) and during the actual implantation period (day 5.5 of pregnancy) was much lower than that in the interimplantation 4. Finding of the differential expression of leptin receptors in implantation sites compared to interimplantation sites suggests that leptin - leptin receptor system may be one of the delicate regulators in the molecular mechanism of the implantation process.
        12.
        1998.12 KCI 등재 서비스 종료(열람 제한)
        비만유전자 산물인 leptin은 지방 조직에서 생성되어 혈액으로 분비되며, 신진대사, 식욕, 체열 등을 조절하여 비만의 억제 조절 물질로 작용하는 것으로 알려져 있다. 또한 leptin은 비만 뿐만 아니라 생식 생리와도 관련이 있는 것으로 보이며, 이러한 leptin의 작용이 난소에 직접적인지 혹은 시상하부나 뇌하수체를 매개로 하는지는 아직 정확하게 밝혀지지 않고 있으며, 난소에서의 leptin 및 leptin 수용체의 발현 양상에 대한 연구 또한 미진