Sestrin 2 (SESN2) is a member of the sestrin family of stress-induced proteins that negatively regulate agingassociated biological processes. This study aims to investigate the role of SESN2 in regulating the differentiation potential and senescence of mesenchymal stem cells (MSCs) derived from young and elderly donors. Bulk RNA sequencing revealed a common decline in the SESN2 mRNA levels in MSCs from elderly individuals, which was confirmed via reverse transcription-polymerase chain reaction and western blot analyses. SESN2 knockdown in MSCs from young donors resulted in phenotypic changes similar to those in MSCs from elderly donors, including an enhanced expression of senescence and adipogenic markers and diminished expression of osteogenic markers. To confirm the effect of decreased SESN2 expression on osteogenic and adipogenic differentiation, we induced Sesn2 knockdown in mouse bone marrow-derived MSCs. Sesn2 knockdown suppressed the mRNA expression of osteogenic marker genes, alkaline phosphatase activity, and matrix mineralization. Furthermore, Sesn2 knockdown enhanced mRNA expression of the adipogenic marker genes and intracellular lipid accumulation. These results suggest that a decline in SESN2 expression during aging contributes to the shift of MSC differentiation from osteogenic to adipogenic lineage.

Background: Despite its anticancer activity, cisplatin exhibits severe testicular toxicity when used in chemotherapy. Owing to its wide application in cancer therapy, the reduction of damage to normal tissue is of imminent clinical need. In this study, we evaluated the effects of catechin hydrate, a natural flavon-3-ol phytochemical, on cisplatin-induced testicular injury. Methods: Type 2 mouse spermatogonia (GC-1 spg cells) were treated with 0-100 μM catechin and cisplatin. Cell survival was estimated using a cell proliferation assay and Ki-67 immunostaining. Apoptosis was assessed via flow cytometry with the Dead Cell Apoptosis assay. To determine the antioxidant effects of catechin hydrate, Nrf2 expression was measured using qPCR and CellROX staining. The anti-inflammatory effects were evaluated by analyzing the gene and protein expression levels of iNOS and COX2 using qPCR and immunoblotting. Results: The 100 μM catechin hydrate treatment did not affect healthy GC-1 spg cells but, prevented cisplatin-induced GC-1 spg cell death via the regulation of anti-oxidants and inflammation-related molecules. In addition, the number of apoptotic cells, cleaved-caspase 3 level, and BAX gene expression levels were significantly reduced by catechin hydrate treatment in a cisplatin-induced GC-1 spg cell death model. In addition, antioxidant and anti-inflammatory marker genes, including Nrf2 , iNOS, and COX2 were significantly downregulated by catechin hydrate treatment in cisplatintreated GC-1 cells. Conclusions: Our study contributes to the opportunity to reintroduce cisplatin into systemic anticancer treatment, with reduced testicular toxicity and restored fertility.

Background: Brassica oleracea var. italica (broccoli), a rich source of antioxidants, can prevent various diseases and improve human health. In this study, we investigated the antioxidative effects of broccoli sprout extract on oxidative stress induced by lipopolysaccharide and cisplatin in cell and organ tissue models. Methods: Antioxidative effect of BSE was evaluated using DPPH and ABTS in RAW 364.7 cells, and effects of BSE on testes were investigated using Cisplatin-induced testicular damage model with an in vitro organ culture system. Results: The DPPH assay showed that the antioxidant activity of the alcoholic broccoli sprout extract was higher than that of the water extract. Additionally, the expression levels of antioxidation-related genes, Nrf2 , Gsr , HO-1, and catalase , were significantly increased in broccoli sprout extract-treated RAW 264.7 cells, and the extract suppressed lipopolysaccharide-induced mitochondrial dysfunction. Based on the results in the RAW 264.7 cell culture, the antioxidative effects of the extracts were investigated in a mouse testis fragment culture. The expression of Nrf2 , HO-1 , and Ddx4 was clearly decreased in cisplatin-treated mouse testis fragments and not in both broccoli sprout extract- and cisplatin-treated mouse testis fragments. In addition, the oxidative marker O-HdG was strongly detected in cisplatin-treated mouse testis fragments, and these signals were reduced by broccoli sprout extract treatment. Conclusions: The results of this study show that broccoli sprout extracts could serve as potential nutraceutical agents as they possess antioxidant effects in the testes.

Brassica oleracea var. italica (broccoli) is a type of cabbage that contains vitamins, minerals, and phytochemicals. Consequently, it is used as a potential nutraceutical source for improving human health by reducing oxidative stress and inflammatory responses. Here, the effects of broccoli sprout extract (BSE) on the inflammatory response were investigated through lipopolysaccharide (LPS)- induced inflammatory mouse models. First, we found that the BSE obviously reduce NO production in RAW 264.7 cells in response to LPS stimulation in in vitro study. Pretreatment with BSE administration improved sperm motility and testicular cell survivability in LPS-induced endotoxemic mice. Additionally, BSE treatment decreased the levels of the pro-inflammatory cytokines TNF-a, IL-1β, and IL-6, and COX-2 in testis of LPS-induced endotoxemic mice models. In conclusion, BSE could be a potential nutraceutical for preventing the excessive immune related infertility.

Bovine mammary epithelial (MAC-T) cells are commonly used to study mammary gland development and mastitis. Lipopolysaccharide is a major bacterial cell membrane component that can induce inflammation. Autophagy is an important regulatory mechanism participating in the elimination of invading pathogens. In this study, we evaluated the mechanism underlying bacterial mastitis and mammary cell death following lipopolysaccharide treatment. After 24 h of 50 μg/mL lipopolysaccharide treatment, a significant decrease in the proliferation rate of MAC-T cells was observed. However, no changes were observed upon treatment of MAC-T cells with 10 μg/mL of lipopolysaccharide for up to 48 h. Thus, upon lipopolysaccharide treatment, MAC-T cells exhibit dose-dependent effects of growth inhibition at 10 μg/mL and death at 50 μg/mL. Treatment of MAC-T cells with 50 μg/mL lipopolysaccharide also induced the expression of autophagy-related genes ATG3, ATG5, ATG10, ATG12, MAP1LC3B, GABARAP-L2, and BECN1. The autophagy-related LC3A/B protein was also expressed in a dose-dependent manner upon lipopolysaccharide treatment. Based on these results, we suggest that a high dose of bacterial infection induces mammary epithelial cell death related to autophagy signals.

The objective of this study is to establish the shelf life of non-pasteurized whole egg, egg yolk and egg white liquid. Each sample was stored for two weeks at 5oC, 10oC, 15oC, and 25oC, and then sensory, microbial, and physicochemical tests were performed periodically. The estimation of shelf life was based on the microbial standards of total viable counts and coliforms. The chemical properties highly correlated with the sensory evaluation were also used. Our results showed that the shelf life was the most influenced by microbial properties. Exceptionally, however, whole egg and white liquid stored at 5oC and 10oC with limited bacterial growth were affected by chemical property. The shelf life of the three non-pasteurized liquids was calculated to be less than one day at over 15oC. At 5oC and 10oC, the shelf life was calculated to be 5 d and 1 d for egg yolk liquid, 5 d and 5 d for egg white, and 7 d and 5 d for whole egg, respectively. Therefore, it is advisable to establish reasonable shelf life in the more specific manner based on consideration of these findings.

We previously demonstrated that epidermal growth factor (EGF) enhances cell migration and invasion of breast cancer cells in a SMAD ubiquitination regulatory factor 1 (SMURF1)-dependent manner and that SMURF1 induces degradation of β-catenin in C2C12 cells. However, the relationship between EGF-induced SMURF1 and β-catenin expression in breast cancer cells remains unclear. So, we investigated if EGF and SMURF1 regulate β-catenin expression in MDAMB231 human breast cancer cells. When MDAMB231 cells were incubated with EGF for 24, 48, and 72 hours, EGF significantly increased expression levels of SMURF1 mRNA and protein while suppressing expression levels of β-catenin mRNA and protein. Overexpression of SMURF1 downregulated β-catenin mRNA and protein, whereas knockdown of SMURF1 increased β-catenin expression and blocked EGF-induced β-catenin downregulation. Knockdown of β-catenin enhanced cell migration and invasion of MDAMB231 cells, while β-catenin overexpression suppressed EGF-induced cell migration and invasion. Furthermore, knockdown of β-catenin enhanced vimentin expression and decreased cytokeratin expression, whereas β -catenin overexpression decreased vimentin expression and increased cytokeratin expression. These results suggest that EGF downregulates β-catenin in a SMURF1-dependent manner and that β-catenin downregulation contributes to EGF-induced cell migration and invasion in MDAMB breast cancer cells.

Receptor activator of nuclear factor-κB ligand (RANKL) is an osteoblast/stromal cell-derived essential factor for osteoclastogenesis. During endochondral bone formation, hypertrophic chondrocytes calcify cartilage matrix that is subsequently resorbed by osteoclasts in order to be replaced by new bone. Hypoxia-induced upregulation of RANKL expression has been previously demonstrated in an in vitro system using osteoblasts; however, the involved mechanism remains unclear in chondrocytes. In the present study, we investigated whether hypoxia regulates RANKL expression in ATDC5 cells, a murine chondrogenic cell line, and hypoxiainducible factor-1α (HIF-1α) mediates hypoxia-induced RANKL expression by transactivating the RANKL promoter. The expression levels of RANKL mRNA and protein, as well as HIF-1α protein, were significantly increased in ATDC5 cells under hypoxic condition. Constitutively active HIF-1α alone significantly increased the levels of RANKL expression under normoxic conditions, whereas dominant negative HIF-1α reduced hypoxia-induced RANKL expression. HIF-1α increased RANKL promoter reporter activity in a HIF-1α binding element-dependent manner in ATDC5 cells. Hypoxia-induced RANKL levels were much higher in differentiated ATDC5 cells, as compared to proliferating ATDC5 cells. These results suggested that under hypoxic conditions, HIF-1α mediates induction of RANKL expression in chondrocytes; in addition, hypoxia plays a role in osteoclastogenesis during endochondral bone formation, at least in part, through the induction of RANKL expression in hypertrophic chondrocytes.

본 연구에서는 국내 대표 식육인 소, 돼지, 닭, 오리의4종 식육과 염소, 양, 말, 칠면조의 4종 식육을 동시에 신속하게 감별할 수 있는 2 set의 multiplex PCR법을 개발하고자 미토콘드리아 16S RNA에서 종 특이부위를 선발하고 각 종에 대한 특이도를 높이기 위하여 인위적인 미스매치를 주어 프라이머를 제작한 후 8종 식육의 274개시료를 대상으로 특이도와 민감도를 조사하였다. 그 결과소, 돼지, 닭, 오리 모든 시료에서 각각 279, 94, 192, 477 bp의 증폭산물이, 말, 양, 염소, 칠면조의 모든 시료에서 각각 152 bp, 271 bp, 670 bp, 469 bp에서 뚜렷한 PCR 유전자 산물이 확인되어 모든 축종에서 100%의 특이도를 나타내어 축종별 감별력이 우수한 것으로 나타났다. 8종의 축종별로 DNA를 10 ng/μl으로 정량한 후 혼합물을 10배씩 단계 희석하여 반응여부를 조사한 결과, 소, 돼지, 오리에서는 100 fg까지, 닭에서는 1 pg까지 검출됨을 확인할수 있었다. 소, 돼지, 닭, 오리고기를 99.9%, 99%, 90%,70%, 50%, 30%, 10%, 1%, 0.1%의 비율로 혼합한 식육과 83℃ 20분, 100℃ 30분, 121℃ 10분에서 각각 열처리한 가열 혼합육에 대하여 검출한계를 조사한 결과 마지막단계의 희석 비율인 모든 혼합육의 0.1%에서 검출이 가능하였으며, 열처리 혼합육에서는 닭에서는 1% 농도에서소와 돼지의 혼합육에서 0.1% 농도에서 검출되어 민감도가 높음을 확인할 수 있었다. 본 연구에서 개발된 multiplex PCR법은 특이도 및 민감도에 있어서 국내 대표 식육을 감별하는데 있어서 유용한 것으로 평가된다.

Osteocytes may function as mechanotransducers by regulating local osteoclastogenesis. Reduced availability of oxygen, i.e. hypoxia, could occur during disuse, bone development, and fracture. Receptor activator of nuclear factor-κB ligand (RANKL) is an osteoblast/stromal cell derived essential factor for osteoclastogenesis. The hypoxia induced osteoclastogenesis via increased RANKL expression in osteoblasts was demonstrated. Hypoxic regulation of gene expression generally involves activation of the hypoxia-inducible factor (HIF) transcription pathway. In the present study, we investigated whether hypoxia regulates RANKL expression in murine osteocytes and HIF-1α mediates hypoxia-induced RANKL expression by transactivating RANKL promoter, to elucidate the role of osteocyte in osteoclastogenesis in the context of hypoxic condition. The expression levels of RANKL mRNA and protein, as well as hypoxia inducible factor-1α (HIF-1α) protein, were significantly increased in hypoxic condition in MLO-Y4s. Constitutively active HIF-1α alone significantly increased the levels of RANKL expression in MLO-Y4s under normoxic conditions, whereas dominant negative HIF-1α blocked hypoxia-induced RANKL expression. To further explore to find if HIF-1α directly regulates RANKL transcription, a luciferase reporter assay was conducted. Hypoxia significantly increased RANKL promoter activity, whereas mutations of putative HIF-1α binding elements in RANKL promoter prevented this hypoxia-induced RANKL promoter activity in MLO-Y4s. These results suggest that HIF-1α mediates hypoxia-induced up-regulation of RANKL expression, and that in osteocytes of mechanically unloaded bone, hypoxia enhances osteoclastogenesis, at least in part, via an increased RANKL expression in osteocytes.

The study of odor generation conditions in urban areas which were outside odor controlled(or management) areas were investigated using the air dilution olfactory method and instrumental analysis in Incheon city. From the study the generation of odor from residential sources and industrial sources was different from region to region. Odor intensity was high in industrial regions in the afternoon, but was low in school regions in urban areas. From the analysis, more effective regional policy suggestions to address different kinds of odor problems in urban areas are proposed.

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit® on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit® on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kitTM resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit® on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit®: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.

Receptor activator of NF-κB ligand (RANKL) is an essential cytokine for osteoclast differentiation, activation and survival. T lymphocytes such as T₁₇ cells, a subset of T helper cells that produce IL-17, play an important role in rheumatoid arthritic bone resorption by producing inflammatory cytokines and RANKL. It has not yet been clearly elucidated how T cell activation induces RANKL expression. T cell receptor activation induces the activation of nuclear factor of activated T cell (NFAT) and expression of its target genes. In this study, we examined the role of NFAT in T cell activation- induced RANKL expression. EL-4, a murine T lymphocytic cell line, was used. When T cell activation was induced by phorbol 12-myristate 13-acetate (PMA) and ionomycin, RANKL expression increased in a time-dependent manner. In the presence of cyclosporin, an inhibitor of NFAT activation, this PMA/ionomycin‐induced RANKL expression was blocked. Overexpression of either NFATc1 or NFATc3 induced RANKL expression. Chromatin immunoprecipitation results demonstrated that PMA/ionomycin treatment induced the binding of NFATc1 and NFATc3 to the mouse RANKL gene promoter. These results suggest that NFATc1 and NFATc3 mediates T cell receptor activationinduced RANKL expression in T lymphocytes.

We investigated the prevalence of the Listeria monocytogenes from livestock processed products in processing plants and retail markets of Korea from 2010 to 2011. A total of 1,380 samples were collected; Meat processed products such as cooked ham and sausage, jerked meat, and meat extract products. Milk processed products such as milk, butter, cheese, and ice cream. Egg processed products such as whole egg liquid and pidan. L. monocytogenes were isolated from samples using listeria enrichment broth, fraser broth and Oxford agar, and counted in Oxford agar. The three of L. monocytogenes strains (1.16%) were isolated from sausages, two (0.73%) from mixed pressed ham and one (0.51%) from jerked meat, respectively. The colony forming unit (CFU) of L. monocytogenes from all samples were below 10 CFU/g. The four isolates (66.6%) were 1/2b except two isolates (1/2a) in the serotypes. Further studies are needed to understand the transmission route of L. monocytogenes, including a survey of food handlers, environments of retail markets, and all potential risk factors in cooked sausages, mixed pressed hams, and jerked meat processing.

Tumor necrosis factor alpha (TNFα) is a multifunctional cytokine that is elevated in inflammatory diseases such as atherosclerosis, diabetes and rheumatoid arthritis. Recent evidence has suggested that β2 adrenergic receptor(β2AR) activation in osteoblasts suppresses osteogenic activity. In the present study, we explored whether TNFα modulates βAR expression in osteoblastic cells and whether this regulation is associated with the inhibition of osteoblast differentiation by TNFα. In the experiments, we used C2C12 cells, MC3T3- E1 cells and primary cultured mouse bone marrow stromal cells. Among the three subtypes of βAR, β2 and β3AR were found in our analysis to be upregulated by TNFα. Moreover, isoproterenol-induced cAMP production was observed to be significantly enhanced in TNFα-primed C2C12 cells, indicating that TNFα enhances β2AR signaling in osteoblasts. TNFα was further found in C2C12 cells to suppress bone morphogenetic protein 2-induced alkaline phosphatase (ALP) activity and the expression of osteogenic marker genes including Runx2, ALP and osteocalcin. Propranolol, a β2AR antagonist, attenuated this TNFα suppression of osteogenic differentiation. TNFα increased the expression of receptor activator of NF-κB ligand (RANKL), an essential osteoclastogenic factor, in C2C12 cells which was again blocked by propranolol. In summary, our data show that TNFα increases β2AR expression in osteoblasts and that a blockade of β2AR attenuates the suppression of osteogenic differentiation and stimulation of RANKL expression by TNFα. These findings imply that a crosstalk between TNFα and β2AR signaling pathways might occur in osteoblasts to modulate their function.

To determine the prevalence of Campylobacter jejuni and Campylobacter coli in meats, a total of 4,161 samples (1,953 domestic and 2,208 imported) were collected from 304 slaughterhouses nationwide and registered cold storages for imported meats in Korea during 2005～2009. The isolation rates of C. jejuni and C. coli in domestic beef, pork, chicken and duck meats were 0.1% (1/630), 0% (0/630), and 0.1% (1/644), 0% (0/644) and 20.5% (125/609), 10.2% (62/609) and 25.7% (18/70), 20.0% (14/70), respectively. In the case of imported meats, C. jejuni were isolated from 0.1% (1/943) and 15.2% (83/546) of pork and chicken meats, respectively, and C. coli were detected only from 4.8% (26/546) of chicken meats. Neither C. jejuni nor C. coli were detected from imported beef, and C. coli were also not detected from imported pork. In conclusion, chicken meats had much higher rate of contamination with Campylobacter compared to beef and pork. Therefore, HACCP system that is now mandatory for slaughterhouses should be actively practiced for safe and sanitary processing, handling, and marketing of chicken meats. In addition, all critical control points should be determined by processing procedures at processing plants as well as farms and slaughterhouses, and monitoring should be carried out at regular intervals.