• Biomolecules & Therapeutics
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• 제18권4호
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• pp.402-410
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• 2010

Although the overproduction of prostaglandin $E_2$ ($PGE_2$) in intestinal epithelial cells has been considered to be highly correlated with the colorectal carcinogenesis, the precise mechanism of action remains poorly elucidated. Accumulating evidence suggests that the PGE receptor (EP)-mediated signal transduction pathway might play an important role in this process. In the present study, we investigated the mechanism of action underlying $PGE_2$-mediated cell proliferation and the effect of resveratrol on the proliferation of human colon cancer cells in terms of the modulating $PGE_2$-mediated signaling pathway. $PGE_2$ stimulated the proliferation of several human colon cancer cells and activated growth-stimulatory signal transduction, including Akt and ERK. $PGE_2$ also increased the phosphorylation of GSK-$3{\beta}$, the translocation of ${\beta}$-catenin into the nucleus, and the expressions of c-myc and cyclin D1. Resveratrol, a cancer chemopreventive phytochemical, however, inhibited $PGE_2$-induced growth stimulation and also suppressed $PGE_2$-mediated signal transduction, as well as ${\beta}$-catenin/T cell factor-mediated transcription in human colon cancer cells. These findings present an additional mechanism through which resveratrol affects the regulation of human colon cancer cell growth.

• The Korean Journal of Physiology and Pharmacology
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• 제4권4호
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• pp.301-309
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• 2000

The purpose of our investigation was to examine the effects of prostaglandin $F_{2{\alpha}}\;(PGF_{2{\alpha}})$ on membrane potentials, $Ca^{2+}-activated\;K^+\;(K_{Ca})$ channels, and delayed rectifier $K^+(K_V)$ channels using the patch-clamp technique in single rabbit middle cerebral arterial smooth muscle cells. $PGF_{2{\alpha}}$ significantly hyperpolarized membrane potentials and increased outward whole-cell K currents. $PGF_{2{\alpha}}$ increased open-state probability of $K_{Ca}$ channels without the change of the open and closed kinetics. $PGF_{2{\alpha}}$ increased the amplitudes of $K_V$ currents with a leftward shift of activation and inactivation curves and a decrease of activation time constant. Our results suggest that the activation of $K_{Ca}$ and $K_V$ channels, at least in part, may lead to attenuate or counteract vasoconstriction by $PGF_{2{\alpha}}$ in middle cerebral artery.

• 한국응용과학기술학회지
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• 제9권2호
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• pp.127-139
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• 1992

This study was separated and identified prostaglandin from garlic by TLC, HPLC, and Gc-Mass. In this experiment aimed at researching the effects of garic on body weight, and serum lipid, protein and glucose in male rats. The male rats applied in this work were 42 of Sprague-Dawley strain. In addition to basal diet, the worker administrated 4 groups of the experimental rats solutions which were 0.2 and 0.4ml of raw garlic juice, and of etanol garlic extract with together 2.5% cholesterol solution solved by corn oil for 8 weeks respectively. These results were as follows. 1. Separated and identified of Prostaglandin from garlic. 2. The growth rate of body weight and food efficiency ratio(FER) appeared to be more increased in the experimental groups administrated ethanol garlic extract than raw garlic juice. 3. The content of serum total cholesterol apperaded to be decreased in the experimental group administrated 0.4ml of ethanol garlic extract. 4. The level of serum HDL-cholesterol had a tendency to be more increased in all the experimental groups administrated garlic than control group. 5. The level of serum glucose appeared to be decreased in all the experimental groups administrated garlic, particularly ethanol garlic extract.

• 한국임상수의학회지
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• 제16권2호
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• pp.389-396
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• 1999

Pregnant rats were treated at various stages of gestation with prostaglandin analogue, cloprostenol alone or concomitant with HCG to study effects on termination of gestation and plasma estrogen and progesterone. Cloprostenol (90 or 180 mg/kg) was administered alone on 1~3, 4~6, 7~9, 9~11 or 11~13 consecutive days of gestation twice a day and in combination with HCG (50 or 100 IU/day) on days of 1~3 or 7~9 once a day. Rats were autopsied on day 21 of gestation or at 6, 12 or 24 hours after treatment on day 6 or 9, respectively. Cloprostenol was found to be nearly 100% effective in preventing implantation, destroying viable fetuses and causing preimplantation losses, but in early gestation, on days 1-3, there was little effect. And when cloprostenol administered concomitant with HCG, corpora lutea were significantly increased, implantation sites and viable fetuses significantly decreased, and pre-and post-implantation losses significantly increased in most cases. Plasma concentrations of estradiol and progesterone were significantly decreased by administering cloprostenol, and estradiol concentration significantly decreased but progesterone significantly increased by administering of cloprostenol concomitant with HCG. It is suggested that cloprostenol was more effective in terminating pregnancy than a combination of cloprostenol and HCG in the rat.

• 대한치과교정학회지
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• 제19권2호
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• pp.25-34
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• 1989

This experiment was performed to study the effect of prostaglandin $E_2$ on tooth movement and root resorption in orthodontically treated cats. Twenty five cats were divided into five groups and closed coil springs delivered 80gm were stretched between upper canine and 3rd premolar. $10{\mu}g$ of $PGE_2$ was injected locally in the submucosal area of the upper right canine, while the left side served as a control and was injected saline 0.1ml. The distance between canine tip and central cusp tip of the 3rd premolar was measured. Scanning electron photomicrographs were made of the coronal half of the distal root surface of canines and cemental craterings were observed and quantified using point-counting volumetry. Data were analyzed by 2-way ANOVA and paired t-test. The results were as follows: 1. The rate of tooth movement of the $PGE_2$ side was increased, particularly at 1 day, compared with the control side. 2. The rate of tooth movement was minimum from 7 days to 10 days. 3. The resorption of root surface of the $PGE_2$ side was decreased from 4 days to 10 days, compared with the control side.

• 대한의생명과학회지
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• 제19권3호
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• pp.261-265
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• 2013

The corpus luteum is a transient endocrine gland essential for regulation of the ovarian cycle as well as for establishing and maintaining pregnancy. Prostaglandin $F_{2{\alpha}}$ (PGF) initiates functional and structural regression of the corpus luteum and therefore is an important regulator of the estrous cycle. It is a matter of debate whether the endothelial cells of the bovine corpus luteum express PGFR, the cognate receptor for PGF. Therefore, the aim of this study was to assess the expression of PGFR in bovine endothelial cells. Endothelial cells were isolated from the bovine corpus luteum of the mid-luteal stage using magnetic beads and cultured in vitro. We demonstrate that this isolation procedure generates a pure culture of endothelial cells as confirmed by synthesis of Factor VIII and lack of expression of $3{\beta}$-hydroxysteroid dehydrogenase. By RT-PCR, Western blot and immunofluorescence analyses, we further show that the cultured endothelial cells produced PGFR. This model system can be utilized to provide an experimental system to investigate the role of PGF on endothelial cells during the reproductive cycle.

• Clinical and Experimental Reproductive Medicine
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• 제24권1호
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• pp.35-42
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• 1997

The present study was designed to define the role of prostaglandin in the development and hatching of mouse embryo. The effects of indomethacin, an inhibitor of prostaglandin synthesis, on the development and hatching of morula and blastocyst were examined. In early morula stage, embryos were degenerated significantly at 100 ${\mu}M$ and 200 ${\mu}M$ indomethacin. However, the viability of embryos was not influenced by concentration in any other embryonic stages. In all embryonic stages, the hatching was suppressed with concentration dependent manner, but expansion was not suppressed. Particularly, in 84h embryos post hCG injection, the hatching was suppressed significantly compared with post hCG 72h or 96h embryos. When embryos were treated with 100 ${\mu}M$ indomethacin for a specific time (12h) in according to the development stage, the hatching was suppressed all groups. These suppressional effect was decreased as embryonic development stage was progressed. However, the expansion was not affected in all treatment group. This study suggests that hatching-related metabolic substances are synthesized from morula stage and intraembryonic signaling mediated prostaglandin was important for development and hatching of mouse embryo.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.390-400
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• 2000

The corpus luteum (CL) is a temporary endocrine gland whose main function is to secrete progesterone to support pregnancy. On the other hand, the cyclic bovine CL has also been shown to be a site of prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$) production. Although there is general agreement that endometrial $PGF_{2{\alpha}}$ is an essential luteolysin in cattle, luteal $PGF_{2{\alpha}}$ seems to play a luteotropic role as an autocrine and/or paracrine factor, especially for the development and maintenance of the CL. This supposition is based on evidence that some of the prerequisites for autocrine/paracrine mechanisms are present, including local production of $PGF_{2{\alpha}}$ and the existence of specific binding sites within the CL. The purpose of this paper is to review the regulation of luteal $PGF_{2{\alpha}}$ secretion, its action on CL as an autocrine and/or paracrine factor and the receptivity of bovine CL to. $PGF_{2{\alpha}}$.

• 동의생리병리학회지
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• 제20권3호
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• pp.724-729
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• 2006

Many traditional herbal remedies exhibit several beneficial effects including anti-inflammation. The exact mechanism of the a-inflammato action of Panax notoginseng Buck F.H. Chen. however, has not been determined. In the present study, we have isolted the acting compound, emodin, from P. notoginseng and examined the effects of p. notoginseng and emodin on lipopolysaccharide (LPS)-induced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) gene expression in RAW264.7 macrophages. The results indicated that p. notoginseng concentration-dependently inhibited LPS-induced NO production. Furthermore, P. notoginseng inhibited the expression of LPS-induced iNOS and COX-2 proteins without an appreciable cytotoxic effect on RAW264.7 cells. Emodin also inhibited LPS-induced iNOS protein as potently as P. notoginseng. This was consistent with the findings that P. notoginseng but not emodin inhibited prostaglandin E2 synthesis induced Dy LPS.

• Biomolecules & Therapeutics
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• 제23권5호
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• pp.458-464
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• 2015

Sennoside A (erythro) and sennoside B (threo) are dianthrone glycosides and diastereomers. We investigated their abilities to prevent the gastric lesions associated with diseases, such as, gastritis and gastric ulcer. To elucidate their gastroprotective effects, the inhibitions of $HCl{\cdot}tOH$-induced gastritis and indomethacin-induced gastric ulcers were assessed in rats. It was observed that both sennoside A and sennoside B increased prostaglandin $E_2$ ($PGE_2$) levels and inhibited $H^+/K^+$-ATPase (proton pump). In a rat model, both compounds reduced gastric juice, total acidity and increased pH, indicating that proton pump inhibition reduces gastric acid secretion. Furthermore, sennoside A and B increased $PGE_2$ in a concentration-dependent manner. In a gastric emptying and intestinal transporting rate experiment, both sennoside A and sennoside B accelerated motility. Our results thus suggest that sennoside A and sennoside B possess significant gastroprotective activities and they might be useful for the treatment of gastric disease.