2,555 research outputs found

    Exopolysaccharide of Enterococcus faecium L15 promotes the osteogenic differentiation of human dental pulp stem cells via p38 MAPK pathway

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    Abstract Background Bone has important functions in the body. Several researchers have reported that the polysaccharides and lipopolysaccharide derived from microbes can promote osteogenic differentiation of stem cells. Enterococcus faecium, a lactic acid bacterium (LAB), produces several bioactive metabolites and has been widely applied in the food and nutraceutical industries. The exopolysaccharide (EPS) from LAB has also been extensively examined for its postbiotic effects and for its in vivo and in vitro functionalities. However, studies on promoting bone differentiation using polysaccharides from LAB are lacking. Therefore, the purpose of this study was to investigate the effect of E. faecium L15 extract and EPS on osteogenic differentiation of human dental pulp stem cells (hDPSCs) and to identify the underlying mechanisms. Methods hDPSCs were obtained from dental pulp tissue, and L15 extract and EPS were isolated from L15. Gene and protein expression of the osteogenic differentiation markers were analyzed with qPCR and western blotting and the possible signaling pathways were also investigated using western blotting. Osteogenic differentiation potential was examined by alkaline phosphatase (ALP) staining and alizarin red s (ARS) staining. In addition, osteogenic differentiation potential of L15 EPS was explored in ex vivo culture of neonate murine calvaria. Results The calcium deposition and ALP activity were enhanced by addition of L15 extract or EPS. The expression levels of RUNX2, ALP, and COL1A1 mRNA and the protein expression levels of RUNX2, ALP, and BMP4 were increased in hDPSCs treated with the L15 extract or EPS. The L15 EPS treatment enhanced phosphorylation of the p38 mitogen-activated protein kinase (MAPK). The L15 EPS-induced increases in RUNX2, ALP, and BMP4 expression were suppressed by the p38 MAPK inhibitor SB203580. The promoting effect of L15 EPS on osteogenic differentiation was not only seen in hDPSCs, but also in osteoblast precursors. ALP activity and the expression of RUNX2, ALP, and COL1A1 increased in the L15 EPS-treated osteoblast precursors. In addition, L15 EPS increased bone thickness of neonate murine calvaria in ex vivo culture. Conclusions The stimulatory effect of L15 extract and EPS on osteogenic differentiation occurred through the p38 MAPK pathway, and L15 EPS enhanced new bone formation in neonate murine calvaria. These data suggest that L15 EPS has therapeutic potential applicable to bone regeneration

    Mesenchymal stem cells genetically engineered to express platelet-derived growth factor and heme oxygenase-1 ameliorate osteoarthritis in a canine model

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    Background Mesenchymal stem cells (MSCs) are used for the treatment of osteoarthritis (OA), and MSC genetic engineering is expected to enhance cartilage repair. Here, we aimed to investigate the effect of MSCs overexpressing platelet-derived growth factor (PDGF) or heme oxygenase-1 (HO-1) in chondrocytes and synovial cells with an OA phenotype and assess the in vivo efficacy of intra-articular injections of these MSCs in canine OA models. Methods Canine adipose-derived MSCs were transfected with canine PDGF (PDGF-MSCs) or HO-1 (HO-1-MSCs) using lentiviral vectors. Canine chondrocytes or synovial cells were stimulated with lipopolysaccharide (LPS) to mimic the inflammatory OA model and then co-cultured with MSCs, PDGF-MSCs, or HO-1-MSCs for 24ā€‰h and 72ā€‰h. The mRNA levels of pro-inflammatory, extracellular matrix-degradative/synthetic, or pain-related factors were measured after co-culture by real-time PCR. Furthermore, a surgery-induced canine OA model was established and the dogs were randomized into four groups: normal saline (nā€‰=ā€‰4), MSCs (nā€‰=ā€‰4), PDGF-MSCs (nā€‰=ā€‰4), and HO-1-MSCs (nā€‰=ā€‰4). The OA symptoms, radiographic OA severity, and serum matrix metallopeptidase (MMP)-13 levels were assessed before and 10ā€‰weeks after treatment, to evaluate the safety and efficacy of the modified MSCs. Results PDGF or HO-1 overexpression significantly reduced the expression of pro-inflammatory factors, MMP-13, and nerve growth factor elicited by LPS and increased that of aggrecan and collagen type 2 in chondrocytes (Pā€‰<ā€‰0.05). In addition, the expression of aggrecanases was significantly downregulated in synovial cells, whereas that of tissue inhibitor of metalloproteinases was upregulated (Pā€‰<ā€‰0.05). Furthermore, the co-cultured MSCs highly expressed genes that contributed to the maintenance of joint homeostasis (Pā€‰<ā€‰0.05). In vivo studies showed that OA symptoms improved after administration of all MSCs. Also, PDGF-MSCs significantly improved limb function and reduced pain (Pā€‰<ā€‰0.05). The results of the radiographic assessment and serum MMP-13 levels did not vary significantly compared to those of the control. Conclusions Genetically modifying PDGF and HO-1 in MSCs is an effective strategy for treating OA, suggesting that PDGF-MSCs can be novel therapeutic agents for improving OA symptoms

    Dokaz protutijela protiv velikog metilja Fasciola hepatica u goveda na otoku Ulleung, Koreja.

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    We performed a cross-sectional study to estimate the seroprevalence of Fasciola hepatica in herds of cattle on Ulleung island, Korea. Blood samples were collected from randomly selected cattle and the sera were separated and analysed with an ELISA to detect antibodies against F. hepatica. The positive samples were classified as mildly, moderately or strongly positive. Out of 405 cattle sera assessed, 38 (9.4%) were seropositive for antibodies against F. hepatica. From these, 2.5% each were moderately or strongly positive and 4.4% were mildly positive. A significantly higher seroprevalence (P<0.05) was observed in young animals (<2 y old, 15.3%) compared to adults (ā‰„2 y old, 5.4%), while no significant difference in seropositivity was found between male and female animals. This is the the first report of F. hepatica seroprevalence in cattle herds in Korea. These findings may be used to establish a base-line of information for future investigations focused on the significance of F. hepatica in Korea.Provedeno je presječno istraživanje radi procjene seroprevalencije invadiranosti velikim metiljem Fasciola hepatica u stadima goveda na otoku Ulleung u Koreji. Uzorci krvi bili su uzeti od nasumce odabranih goveda, a odvojeni uzorci seruma bili su pretraženi imunoenzimnim testom na prisutnost protutijela specifičnih za velikog metilja. Pozitivni uzorci bili su svrstani u skupine: slabo, umjereno i jako pozitivni. Od 405 pretraženih uzoraka seruma, 38 (9,4%) je bilo pozitivnih na protutijela specifična za metilj F. hepatica. Od toga je 2,5% uzoraka bilo umjereno ili jako pozitivno, a 4,4% slabo pozitivno. Značajno veća seroprevalencija (P<0,05) ustanovljena je u mladih životinja (u dobi manjoj od dvije godine, 15,3%) u usporedbi s odraslima (ā‰„2 godine, 5,4%), dok nije ustanovljena značajna razlika u seropozitivnosti između mužjaka i ženki. Ovo je prvo izvjeŔće o seroprevalenciji velikog metilja u stadima goveda u Koreji. Nalazi mogu biti od koristi za buduća istraživanja o značenju velikog metilja F. hepatica u Koreji

    Dokaz protutijela protiv velikog metilja Fasciola hepatica u goveda na otoku Ulleung, Koreja.

    Get PDF
    We performed a cross-sectional study to estimate the seroprevalence of Fasciola hepatica in herds of cattle on Ulleung island, Korea. Blood samples were collected from randomly selected cattle and the sera were separated and analysed with an ELISA to detect antibodies against F. hepatica. The positive samples were classified as mildly, moderately or strongly positive. Out of 405 cattle sera assessed, 38 (9.4%) were seropositive for antibodies against F. hepatica. From these, 2.5% each were moderately or strongly positive and 4.4% were mildly positive. A significantly higher seroprevalence (P<0.05) was observed in young animals (<2 y old, 15.3%) compared to adults (ā‰„2 y old, 5.4%), while no significant difference in seropositivity was found between male and female animals. This is the the first report of F. hepatica seroprevalence in cattle herds in Korea. These findings may be used to establish a base-line of information for future investigations focused on the significance of F. hepatica in Korea.Provedeno je presječno istraživanje radi procjene seroprevalencije invadiranosti velikim metiljem Fasciola hepatica u stadima goveda na otoku Ulleung u Koreji. Uzorci krvi bili su uzeti od nasumce odabranih goveda, a odvojeni uzorci seruma bili su pretraženi imunoenzimnim testom na prisutnost protutijela specifičnih za velikog metilja. Pozitivni uzorci bili su svrstani u skupine: slabo, umjereno i jako pozitivni. Od 405 pretraženih uzoraka seruma, 38 (9,4%) je bilo pozitivnih na protutijela specifična za metilj F. hepatica. Od toga je 2,5% uzoraka bilo umjereno ili jako pozitivno, a 4,4% slabo pozitivno. Značajno veća seroprevalencija (P<0,05) ustanovljena je u mladih životinja (u dobi manjoj od dvije godine, 15,3%) u usporedbi s odraslima (ā‰„2 godine, 5,4%), dok nije ustanovljena značajna razlika u seropozitivnosti između mužjaka i ženki. Ovo je prvo izvjeŔće o seroprevalenciji velikog metilja u stadima goveda u Koreji. Nalazi mogu biti od koristi za buduća istraživanja o značenju velikog metilja F. hepatica u Koreji

    Toxicity and Toxin Composition of Microcystis aeruginosa from Wangsong Reservoir

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    Objective: The increasing world population, resulting in increased anthropogenic water pollution, is negatively impacting the limited available water resources. In South Korea, this similarly affects the water quality of reservoirs. As water is a basic necessity for life, water quality monitoring is essential but typically does not include toxicity testing. However, as toxic bloom event frequencies are increasing, this previously neglected aspect becomes pertinent. Therefore, in the present study, the toxin composition and toxicity of a Microcystis aeruginosa strain isolated from a persistent bloom in lake Wangsong, South Korea, was investigated. Methods: A combination of bioassays and chemical analysis was used for this purpose. The bioassay species included terrestrial and aquatic plants, an alga, a rotifer, a tubificid annelid, and crustaceans, representing various trophic levels. Results: The strain was found to produce microcystin-LR, -RR, and YR, as well as Ī²-N-methylamino-L-alanine. The bioassays indicated that the primary producers were less sensitive to the crude extract. Conclusion: The presence or absence of a visible cyanobacterial bloom is also not an indication of the toxins that may be present in the afflicted waters, and thus does not predict exposure risk. Similarly, the presence and absence of toxins and mixtures thereof do not indicate the ecological effect. Therefore, it would be advantages to include toxicity testing into routine water testing regimes to better understand the impact of harmful algal blooms.Peer reviewe

    Adenosine A2A Receptor Agonist, Polydeoxyribonucleotide Treatment Improves Locomotor Function and Thermal Hyperalgesia Following Neuropathic Pain in Rats

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    Purpose Lithotomy position has been widely used in the various urologic surgery. Occasionally sensory and motor problems of the lower extremities are occurred due to the lithotomy position and these deficits may be related with sciatic nerve injury (SNI). Inflammatory process is a factor to induce functional impairment after SNI. Therefore, we evaluated the role of adenosine A2A receptor agonists, polydeoxyribonucleotide (PDRN) showing anti-inflammatory effect on locomotor function following SNI in rats. Methods Sciatic nerve was compressed with surgical clips for 1 minute after exposing of right sciatic nerve. After 3 days of SNI, PDRN (2, 4, and 8 mg/kg) was applied to the damaged area of sciatic nerve once daily for 10 days. Walking track analysis was conducted for locomotor function and plantar test was performed for thermal pain sensitivity. Level of cyclic adenosine-3Ā“,5Ā“-monophosphate (cAMP) were measured using enzyme-linked immunosorbent assay. Western blot analysis was performed for tumor necrosis factor (TNF)-Ī±, interleukin (IL)-1Ī², cAMP response element binding protein (CREP), vascular endothelial growth factor (VEGF). Immunofluorescence for neurofilament was also conducted. Results Locomotor function was decreased and thermal pain sensitivity was increased by SNI. SNI enhanced proinflammatory cytokinesā€™ production, such as TNF-Ī± and IL-1Ī², while suppressed CREP phosphorylation and cAMP level. SNI also reduced the expression of VEGF and neurofilaments. However, treatment with PDRN inhibited proinflammatory cytokinesā€™ production and upregulated CREP phosphorylation and cAMP expression. PDRN also enhanced the expression of VEGF and neurofilaments. As a result, PDRN improved locomotor function and alleviated thermal hyperalgesia after SNI. Conclusions PDRN has shown potential to be used as an effective treatment for neuropathic pain

    Formate Dehydrogenase (FDH1) Localizes to Both Mitochondria and Chloroplast to Play a Role in Host and Nonhost Disease Resistance

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    Nonhost disease resistance is the most common type of plant defense mechanism against potential pathogens. In this study, the metabolic enzyme formate dehydrogenase (FDH1) was identified to be involved in nonhost disease resistance in Nicotiana benthamiana and Arabidopsis thaliana. In Arabidopsis, AtFDH1 was highly upregulated in response to both host and nonhost bacterial pathogens. Arabidopsis Atfdh1 mutants were compromised in nonhost resistance, basal resistance, and gene-for-gene resistance. The expression patterns of salicylic acid (SA) and jasmonic acid (JA) marker genes after pathogen infections in Atfdh1 mutant indicated that SA is most likely involved in the FDH1-mediated plant defense response to both host and nonhost bacterial pathogens. Previous studies reported that FDH1 localizes to only mitochondria, or both mitochondria and chloroplasts. Our results showed that the AtFDH1 localized to mitochondria and the amount of FDH1 localized to mitochondria increased upon infection with host or nonhost pathogens. Interestingly, the subcellular localization of FDH1 was observed in both mitochondria and chloroplasts after infection with a nonhost pathogen in Arabidopsis. We speculate that FDH1 plays a role in cellular signaling networks between mitochondria and chloroplasts to produce coordinated defense responses such as SA-induced reactive oxygen species (ROS) generation and hypersensitive response (HR)-induced cell death against nonhost bacterial pathogens
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