• Molecules and Cells
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• v.20 no.1
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• pp.69-73
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• 2005

The flavonoid, quercetin, is a low molecular weight substance found in apple, tomato and other fruit. Besides its antioxidative effect, quercetin, like other flavonoids, has a wide range of neuropharmacological actions including analgesia, and motility, sleep, anticonvulsant, sedative and anxiolytic effects. In the present study, we investigated its effect on mouse 5-hydroxytryptamine type 3 ($5-HT_{3A}$) receptor channel activity, which is involved in pain transmission, analgesia, vomiting, and mood disorders. The $5-HT_{3A}$ receptor was expressed in Xenopus oocytes, and the current was measured with the two-electrode voltage clamp technique. In oocytes injected with $5-HT_{3A}$ receptor cRNA, quercetin inhibited the 5-HT-induced inward peak current ($I_{5-HT}$) with an $IC_{50}$ of $64.7{\pm}2.2{\mu}M$. Inhibition was competitive and voltage-independent. Point mutations of pre-transmembrane domain 1 (pre-TM1) such as R222T and R222A, but not R222D, R222E and R222K, abolished inhibition, indicating that quercetin interacts with the pre-TM1 of the $5-HT_{3A}$ receptor.

• International Journal of Oral Biology
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• v.37 no.3
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• pp.137-145
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• 2012

Aggregatibacter actinomycetemcomitans is the most important etiologic agent of aggressive periodontitis and can interact with endothelial cells. Monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) are chemokines, playing important roles in periodontal pathogenesis. In our current study, the effects of A. actinomycetemcomitans on the production of MCP-1 and IL-8 by human umbilical vein endothelial cells (HUVEC) were investigated. A. actinomycetemcomitans strongly induced the gene expression and protein release of both MCP-1 and IL-8 in a dose- and time-dependent manner. Dead A. actinomycetemcomitans cells were as effective as live bacteria in this induction. Treatment of HUVEC with cytochalasin D, an inhibitor of endocytosis, did not affect the mRNA up-regulation of MCP-1 and IL-8 by A. actinomycetemcomitans. However, genistein, an inhibitor of protein tyrosine kinases, substantially inhibited the MCP-1 and IL-8 production by A. actinomycetemcomitans, whereas pharmacological inhibition of each of three members of mitogen-activated protein (MAP) kinase family had little effect. Furthermore, gel shift assays showed that A. actinomycetemcomitans induces a biphasic activation (early at 1-2 h and late at 8-16 h) of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and an early brief activation (0.5-2 h) of activator protein-1 (AP-1). Activation of canonical NF-${\kappa}B$ pathway ($I{\kappa}B$ kinase activation and $I{\kappa}B-{\alpha}$ degradation) was also demonstrated in these experiments. Although lipopolysaccharide from A. actinomycetemcomitans also induced NF-${\kappa}B$ activation, this activation profile over time differed from that of live A. actinomycetemcomitans. These results suggest that the expression of MCP-1 and IL-8 is potently increased by A. actinomycetemcomitans in endothelial cells, and that the viability of A. actinomycetemcomitans and bacterial internalization are not required for this effect, whereas the activation of protein tyrosine kinase(s), NF-${\kappa}B$, and AP-1 appears to play important roles. The secretion of high levels of MCP-1 and IL-8 resulting from interactions of A. actinomycetemcomitans with endothelial cells may thus contribute to the pathogenesis of aggressive periodontitis.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1701-1707
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• 2005

This study deals with the characterization of porcine PIK3C3 and association tests with quantitative traits. PIK3C3 belongs to the class 3 PI3Ks that participate in the regulation of hepatic glucose output, glycogen synthase, and antilipolysis in typical insulin target cells such as those in the such as liver, muscle system, and fat. On the analysis of full-length mRNA sequence, the length of the PIK3C3 CDS was recorded as 2,664 bps. As well, nucleotide and amino acid identities between human and pig subjects were 92% and 99%, respectively. Five SNPs were detected over 5 exons. We performed genotyping by using a SNP C2604T on exon24 for 145 F$_2$ animals (from a cross between Korean native boars and Landrace sows) by PCR-RFLP analysis with Hpy8I used to investigate the relationship between growth and fat depot traits. In the total association analysis, which doesn' consider transmission disequilibrium, the SNP showed a significant effect (p<0.05) on body weight and carcass fat at 30 weeks of age as well as a highly significant effect (p<0.01) on back fat. In an additional sib-pair analysis, C allele still showed positive and significant effects (p<0.05) on back fat thickness and carcass fat. Moreover, the effects of C allele on the means of within-family components for carcass fat and back fat were estimated as 2.76 kg and 5.07 mm, respectively. As a result, the SNP of porcine PIK3C3 discovered in this study could be utilized as a possible genetic marker for the selection of pigs that possess low levels of back fat and carcass fat at the slaughter weight.

• IMMUNE NETWORK
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• v.14 no.1
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• pp.45-53
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• 2014

Osteoarthritis (OA) is a degenerative joint disease characterized by a progressive loss of cartilage. And, increased oxidative stress plays a relevant role in the pathogenesis of OA. Ursodeoxycholic acid (UDCA) is a used drug for liver diseases known for its free radical-scavenging property. The objectives of this study were to investigate the in vivo effects of UDCA on pain severity and cartilage degeneration using an experimental OA model and to explore its mode of actions. OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration UDCA was initiated on the day of MIA injection. Limb nociception was assessed by measuring the paw withdrawal latency and threshold. Samples were analyzed macroscopically and histologically. Immunohistochemistry was used to investigate the expression of interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, nitrotyrosine and inducible nitric oxide synthase (iNOS) in knee joints. UDCA showed an antinociceptive property and attenuated cartilage degeneration. OA rats given oral UDCA significantly exhibited a decreased number of osteoclasts in subchondral bone legion compared with the vehicle-treated OA group. UDCA reduced the expression of IL-$1{\beta}$, IL-6, nitrotyrosine and iNOS in articular cartilage. UDCA treatment significantly attenuated the mRNA expression of matrix metalloproteinase-3 (MMP-3), -13, and ADAMTS5 in IL-$1{\beta}$-stimulated human OA chondrocytes. These results show the inhibitory effects of UDCA on pain production and cartilage degeneration in experimentally induced OA. The chondroprotective properties of UDCA were achieved by suppressing oxidative damage and inhibiting catabolic factors that are implicated in the pathogenesis of cartilage damage in OA.

• Applied Microscopy
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• v.39 no.2
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• pp.81-87
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• 2009

Diabetic retinopathy is one of major complications of diabetes mellitus, which is associated with the dysfunction of retina. It has been reported that the onset of diabetic retinopathy is related to the activation of renin-angiotensin system (RAS). Angiotensin converting enzyme (ACE), which converts angiotensin I into angiotensin II, is a key component of RAS. Among many growth factors, vascualr endothelial growth factor (VEGF) is an important cytokine in the neovasculization of retina, which is a characteristics of diabetic retinopathy. However, the relationship between ACE and VEGF was not elucidated in diabetic retinopathy. Thus, this study was conducted to examine the protective effect of captopril, an ACE inhibitor, in the retina of streptozotocin (STZ)-treated diabetic rats. In present study, STZ-treated diabetic rats exhibited the increase of VEGF levels in serum and retina. The serum levels of VEGF in STZ-treated diabetic rats was not blocked by the treatment of captopril. However, the retina levels of VEGF in STZ-treated diabetic rats was blocked by the treatment of captopril, suggesting the local action of captopril in retina. Immunohistochemical analysis also revealed that the retina of STZ-treated diabetic rats manifested the increase of ganglion cell layers, outer nuclear layers, and inner nuclear layers, which were also prevented by the treatment of captopril. In conclusion, captopril prevented the expression of VEGF in the retina of STZ-treated diabetic rats.

• Development and Reproduction
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• v.4 no.2
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• pp.237-242
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• 2000

Growth hormone releasing hormone (GHRH), the major hypothalamic stimulus of GH secretion from the anterior pituitary gland, has been found to be present in several extrahypothalamic sites including placenta testis, ovary and anterior pituitary gland. The present study was performed to elucidate the role of pituitary GHRH on proliferation of cells derived from rat anterior pituitary gland. The GHRH content of pituitary tissue, cultured pituitary cells, and the conditioned media was evaluated by radioimmunoassay (RIA). Primary cultures of pituitary cells derived from adult rats were prepared by enzymatic dispersion. Significant amounts of GHRH-like molecules were detected in both pituitary tissue and cell cultures by GHRH RIA. Competition curves with increasing amounts of tissue extracts and conditioned media were parallel with those of standard peptide, indicating that the pituitary GHRH-like material is similar to authentic GHRH. To analyze specific cell types responsible for producing GHRH in anteroior pituitary, cell fractionation technique combined with GHRH RIA was performed. In cell fractionation experiment, the highest level of GHRH content was found in gonadotrope enriched-fraction and followed by somatotrope-, lactotrope- and thyrotrope-fraction. Treatment of pituitary cells with GHRH resulted in a dose-dependent increase in [$^3$H] thymidine incorporation. The mitogenic effect of GHRH could be mediated by typical oncogenic activation since the GHRH induced transient increase in c-fos mRNA levels with peak response at 30 minutes. The present study demonstrated that i) the pituitary GHRH expressed in the rat anterior pituitary gland can be secreted, ii) among the various cell types, gonadotropes and somatotorpes are the major GHRH source, and iii) the GHRH treatment increased the [$^3$H] thymidine incorporation and c-fos transcriptional activity in the pituitary cell culture. These findings suggested that GHRH could participated in the paracrine and/or autocrine regulation of cell proliferation, as well as promoting growth hormone secretion.

• Development and Reproduction
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• v.11 no.2
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• pp.85-96
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• 2007

Mesenchymal stem cells (MSC) are promising candidates for cell-based therapies. One major obstacle for their clinical use is the unsafety of fetal bovine serum (FBS), which is a crucial part of all media currently used for the culture of MSC. We investigated the effect of human cord serum (HCS) on the growth response, mRNA and protein expressions of human amnion-derived stem cells (HAM). HAM were isolated from the amnion after a Caesarean section and cultured in DMEM supplemented with 10% FBS, 5% HCS or 10% HCS. During culture, their biological characteristics at earlier and later passages were analyzed using RT-PCR and immunocytochemistry. Regardless of serum sources, HAM showed the prominent expression of Oct-4, Rex-1, SCF, FGF-5, BMP-4, nestin, GATA-4, NCAM and HLA ABC genes. The expression profile was observed even at later passages. Similarly, HAM cultured in either FBS or HCS exhibited the distinct protein expression of collagen I, II, III and XII, fibronectin, $\alpha$-smooth muscle actin, vimentin, CK18, CD54, FSP, TRA-1-60, SSEA-3, -4 and HLA ABC. However, desmin expression was only observed in HAM cultured in medium supplemented with FBS and vWF expression was only found in HAM cultured in medium supplemented with HCS. Overall pattern of gene and protein expression of HAM was typical of known adult stem cells such as bone marrow-derived MSC. In conclusion, HCS could be as effective as FBS for the culture of HAM.

• Journal of Animal Science and Technology
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• v.59 no.7
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• pp.16.1-16.6
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• 2017

Background: This study was performed to investigate the impact of exogenous ghrelin on the pancreatic ${\alpha}$-amylase outputs and responses of pancreatic proteins to ghrelin that may relate to pancreatic exocrine. Methods: Sprague-Dawley male rats (9 weeks old, $300{\pm}10g$) were injected with ghrelin via intraperitoneal (i.p.) infusion at dosage of 0, 0.1, 1.0 and $10.0{\mu}g/kg$ body weight (BW), respectively. The plasma ghrelin and cholecystokinin (CCK) level were determined using enzyme immunoassay kit; the mRNA expression of ghrelin receptor ($GHSR-1{\alpha}$) and growth hormone (GH) receptor were assessed by reverse transcription PCR; the expressions of pancreatic ${\alpha}$-amylase activity, extracellular-signal-regulated kinases (ERK), phosphorylated extracellular-signal-regulated kinases (pERK) and c-Jun N-terminal kinase (JNK) were evaluated by western blotting; moreover the responses of pancreatic proteins to ghrelin were analyzed using the two-dimensional gel electrophoresis system. Results: The exogenous ghrelin (1.0 and $10.0{\mu}g/kg\;BW$) elevated the level of plasma ghrelin (p < 0.05), and suppressed the expression of pancreatic ${\alpha}$-amylase at a dose of $10.0{\mu}g/kg\;BW$ (p < 0.05). No difference in the level of plasma CCK was observed, even though rats were exposed to any dose of exogenous ghrelin. In addition, a combination of western blot and proteomic analysis revealed exogenous ghrelin ($10.0{\mu}g/kg\;BW$) induced increasing the JNK and ERK expressions (p < 0.05) and four proteins such as Destrin, Anionic trypsin-1, Trypsinogen, and especially eukaryotic translation initiation factor 3 in rat pancreas. Conclusions: Taken together, exogenous ghrelin by i.p. infusion plays a role in the pancreatic exocrine secretion via mitogen-activated protein kinase signaling pathway.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.5
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• pp.625-630
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• 2013

Erectile dysfunction (ED) is a highly prevalent disorder that affects millions of men worldwide. ED is now considered an early manifestation of atherosclerosis, and consequently, a precursor of systemic vascular disease. Lycii fructus extracts (LFE) were administered for 4 weeks to assess the improving effects on ED. Animals were divided into one normal group and four LFE-treated groups (0, 0.3, 0.6, and 1.2 g/kg). We induced ED in the study animals by oral administration of 20% ethanol instead of water everyday for 4 weeks. This study was designed to investigate the effects of LFE on the mRNA levels of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) expression; NO levels of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP); blood profile; and erectile response of the corpus cavernosum of the rat penis. The libido of the LFE-administered male rats was higher than that of the ethanol control group. The erectile response of the corpus cavernosum was restored after LFE administration, to a level similar to the normal group. In addition, the iNOS in the corpus cavernosum of the male rats administered LFE decreased. In contrast, compared to the control group, LFE-administered male rats showed increased eNOS, NO and cGMP levels in the corpus cavernosum. These results indicate that LFE effectively restored ethanol-induced ED in male rats.

• Research in Plant Disease
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• v.21 no.4
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• pp.315-320
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• 2015

Soybean mosaic virus (SMV) is a prevalent pathogen that causes significant yield reduction in soybean production worldwide. SMV belongs to potyvirus and causes typical symptoms such as mild mosaic, mosaic and necrosis. SMV is seed-borne and also transmitted by aphid. Eleven SMV strains, G1 to G7, G5H, G6H, G7H, and G7a were reported in soybean varieties in Korea. A reverse transcription loop-mediated isothermal amplification (RT-LAMP) method allowed one-step detection of gene amplification by simple procedure and needed only a simple incubator for isothermal template. This RT-LAMP method allowed direct detection of RNA from virus-infected plants without thermal cycling and gel electrophoresis. In this study, we designed RT-LAMP primers named SML-F3/B3/FIP/BIP from coat protein gene sequence of SMV. After the reaction of RT-LAMP, products were identified by electrophoresis and with the detective fluorescent dye, SYBR Green I under daylight and UV light. Optimal reaction condition was at $58^{\circ}C$ for 60 min and the primers of RT-LAMP showed the specificity for nine SMV strains tested in this study.