Sphingosine-1-phosphate hinders the osteogenic differentiation of dental pulp stem cells in association with AKT signaling pathways / 国际口腔科学杂志·英文版

Sphingosine-1-phosphate (S1P) is an important lipid mediator that regulates a diverse range of intracellular cell signaling pathways that are relevant to tissue engineering and regenerative medicine. However, the precise function of S1P in dental pulp stem cells (DPSCs) and its osteogenic differentiation remains unclear. We here investigated the function of S1P/S1P receptor (S1PR)-mediated cellular signaling in the osteogenic differentiation of DPSCs and clarified the fundamental signaling pathway. Our results showed that S1P-treated DPSCs exhibited a low rate of differentiation toward the osteogenic phenotype in association with a marked reduction in osteogenesis-related gene expression and AKT activation. Of note, both S1PR1/S1PR3 and S1PR2 agonists significantly downregulated the expression of osteogenic genes and suppressed AKT activation, resulting in an attenuated osteogenic capacity of DPSCs. Most importantly, an AKT activator completely abrogated the S1P-mediated downregulation of osteoblastic markers and partially prevented S1P-mediated attenuation effects during osteogenesis. Intriguingly, the pro-inflammatory TNF-α cytokine promoted the infiltration of macrophages toward DPSCs and induced S1P production in both DPSCs and macrophages. Our findings indicate that the elevation of S1P under inflammatory conditions suppresses the osteogenic capacity of the DPSCs responsible for regenerative endodontics.

Role of IL-32 Gamma on Bone Metabolism in Autoimmune Arthritis

IL-32 acts as a pro-inflammatory cytokine by inducing the synthesis of inflammatory molecules as well as promoting the morphological changes involved in the transformation of monocytes into osteoclasts (OCs). Evaluation of the functions of IL-32 has mainly focused on its inflammatory properties, such as involvement in the pathogenesis of various autoimmune diseases. Recently, IL-32 was shown to be involved in bone metabolism, in which it promotes the differentiation and activation of OCs and plays a key role in bone resorption in inflammatory conditions. IL-32γ also regulates bone formation in conditions such as ankylosing spondylitis and osteoporosis. In this review, we summarize the results of recent studies on the role of IL-32γ in bone metabolism in inflammatory arthritis.

Interleukin-32 Gamma as a New Face in Inflammatory Bone Diseases

Interleukin-32 (IL-32), a recently identified pro-inflammatory cytokine, is involved in the pathogenesis and progression of infections, cancer, chronic inflammation, and autoimmune disease. IL-32γ is the most active isoform in cell death and cell activation among nine distinct isoforms of IL-32. IL-32γ potentiates both osteogenic and osteoclastogenic capacities, and is critical in the coupling of bone resorption and bone formation for maintenance of bone homeostasis. IL-32γ is strongly associated with inflammatory bone disorders such as rheumatoid arthritis, ankylosing spondylitis, and osteoporosis. In this review, we summarize current research on the role of IL-32γ in inflammatory bone disorders, highlighting this cytokine as a novel target for prognostic marker and control of these diseases.

Protective Effect of Melatonin on the Nephrotoxicity by Cisplatin / 대한신장학회잡지

BACKGROUND: Cisplatin (CP), an antitumor agent widely used in the treatment of cancers, has nephrotoxicity. This side effect is closely related to oxidative stress. In the present study, we attempted to reduce CP-induced nephrotoxicity in rats by administering melatonin, an antioxidant. METHODS: Male Sprague-Dawley rats were divided into different groups and were treated as follows: (1) saline control; (2) CP (16 mg/kg, i.p.); (3) CP plus melatonin (10 mg/kg, i.p.). The rats were sacrificed at the 6th day after CP treatment. To evaluate renal damage, BUN, serum creatinine, creatinine clearance and microscopic examination were done. Hydrogen peroxide which is one of the oxygen free radicals, and malondialdehyde which is known as a marker of the oxygen free radical mediated injury, and the activities of the antioxidant enzymes such as superoxied dismutase, catalase, and glutathione peroxidase were also measured. RESULTS: CP-treated rats showed the increase of BUN, serum creatinine, malondialdehyde, hydrogen peroxide and superoxide dismutase (SOD) in kidney. And CP-treated rats also showed the decrease of creatinine clearance and catalase levels. CP-treated rats showed severe tubular necrosis in proximal convoluted tubules under the light microscopic examination. The light microscopic finding and all of the parameters except SOD were restored in the rats injected with CP plus melatonin than those with CP alone. SOD level was higher in the rats injected with CP plus melatonin than that with CP alone. CONCIUSION: These results suggest that melatonin suppresses CP-induced nephrotoxicity by suppressing the production of reactive oxygen species via the activation of SOD and catalase.

Metabolism of Reactive Oxygen Species in Neutrophils from Patients with End-Stage Renal Disease / 대한신장학회잡지

BACKGROUND: The present study was aimed to know the cause of impaired bactericidal activity, especially the metabolism of oxygen free radicals in neutrophils from patients with end-stage renal disease (ESRD). METHODS: We measured the amount of superox ide anion, the activity of three antioxidant enzymes, myeloperoxidase, copper ion level, zinc ion level and the amount of malondialdehyde in neutrophils from patients with ESRD before and after hemodialysis. Reverse transcription-polymerase chain reaction (RT-PCR) for superoxide dismutase (SOD) was also done. RESULTS: The malondialdehyde level, the amount of superoxide anion, catalase, and myeloperoxidase levels in the neutrophils from the patients with ESRD were higher than those from healthy controls. SOD activity, hydrogen peroxide level and zinc level were lower in ESRD patients. On the RT-PCR, the relative index, which is defined the ratio of the band densities for SOD to glyceraldehyde 3-phosphate dehydrogenase, was decreased in neutrophils from patients with ESRD. Glutathione peroxidase activity in the neutrophils from ESRD patients did not show any significant change. CONCLUSION: These results indicate that there are some alterations in metabolism of oxygen free radicals including lower levels of hydrogen peroxide which exerting a direct germicidal ability, due to decreased gene expression and mineral levels. And these alterations might be one of the major mechanisms of impaired microbicidal activity in patients with ESRD.

Effect of Melatonin on the Cisplatin Induced Ototoxicity in Rats / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Cisplatin (CP), an antitumor agent widely used in the treatment of head and neck cancers, has side effects such as ototoxicity and nephrotoxicity. These side effects are closely related to oxidative stress. In the present study, we attempted to suppress CP-induced ototoxicity in rats by administering melatonin, an antioxidant. MATERIALS AND METHOD: Male Sprague-Dawley rats were divided into different groups and were treated as follows: 1) saline control, 2) CP (16 mg/kg, i.p.), 3) CP plus melatonin (10 mg/kg, i.p.). The rats were sacrificed at the 6th day after CP treatment. RESULTS: CP-treated rats showed increase in cochlear malondialdehyde, hydrogen peroxide, glutathione peroxidase and glutathione reductase levels, and the decrease in cochlear superoxide dismutase (SOD) and catalase levels. CP-treated rats showed markedly decreased in the number of stereocilia on the inner hair cells and mildly decreased in the number of outer hair cells in organ of Corti under the light and scanning electron microscopic examination. Light and electron microscopic findings, and cochlear hydrogen peroxide, malondialdehyde, SOD, catalase, glutathione peroxidase and glutathione reductase levels were restored in the rats injected with CP plus melatonin than those with CP alone. CONCLUSION: These results suggest that melatonin suppresses CP-induced ototoxicity via the suppression of the increased production of reactive oxygen species.

Rapid detection of aneuploidy in uncultured fetal cord blood cells by FISH ( Fluorescence In Situ Hybridization ) / 대한산부인과학회잡지

OBJECTIVE: To determine the fetal aneuploidy in fetal blood cells from cordocentesis. METHODS: We analyzed their karyotype and performed fluorescence in situ hybridization(FISH) for chromosome 18, 21, X, and Y in 14 cases of fetal blood cells from cordocentesis at Department of Obstetrics & Gynecology, College of Medicine, Seoul National University and Hamchoon Women's Clinic. RESULTS: In all cases we obtained the consistent results in both methods and were able to rapidly detect aneuploidy in uncultured fetal blood cells using FISH before karyotyping with culture for 48 hr. The averages for accuracy of FISH were from 84.6 % to 93.9%. CONCLUSION: In this study we suggest that the rapid detection in uncultured fetal blood using FISH is possible and that this diagnostic method will be clinically useful when rapid result would be demanded.

Application of FISH(Fluorescence In Situ Hybridization) in uncultured chorionic villus cells / 대한산부인과학회잡지

OBJECTIVE: The cytogenetic analysis for earlier detection of fetal chromosome aneuploidies is performed from chorionic villus using either long-term culture or direct chromosome preparation. To analyze the cause of pregnancy loss, we also attempt the cytogenetic study in product of conception(POC) using chorionic villi or fetal tissue. But the failure of analysis often occurs in direct preparation of villus cells and product of conception(POC). We studied to evaluate the clinical usefulness of FISH in uncultured chorionic villus cells of culture-failed cases. METHODS: According to the patient's indication, we performed FISH for chromosome 18, 21, X and Y in chorionic villi as well as POC and compared FISH results with their chromosomal studies. RESULTS: We found one trisomy 18 and one trisomy 21 in Chorionic Villus Sampling and one trisomy 18 and one monosomy X(45, X) in POC. The averages for accuracy of FISH were 83-91% and all cases are represented consistent results with their chromosomal studies. Among them, we could analyze using FISH only in 5 cases of culture failure including one case of monosomy X in POC. CONCLUSION: We could detect aneuploidy with uncultured chorionic villus cells in case of culture failure, using FISH, it may be the potential method to assist the cytogenetic study.

Detection of Down Syndrome & Edward Syndrome in uncultured amniocytes using FISH ( Fluorescence In Situ Hybridization / 대한산부인과학회잡지

FISH is suggested as a possible method to detect the numerical and structural abnormalities of chromosomes in interphase nucleus. We performed this study to discuss the clinical usefulness of FISH in uncultured amniocytes and to set up the cut-off value for further study. We collected amniotic fluid samples from patients whose chromosome studies were recommended due to screen positive for Down and Edword syndrome in triple marker test using maternal serum. The centromeric probe for chromosome 18 and the locus-specific probe for chromosome 21 were used and the results were compared to their karyotypes. We could find 2 cases of trisony 21 and 2 cases of trisony 18 and the other cases represented normal karyotypes. The accuracies were 91% for disomy 18, 89% for trisomy 18, 92% for disomy 21 and 88% for trisomy 21. Therefore FISH technique is a possible method to detect the chromosomal abnormalities in uncultured amniocytes and the use of locus-specific probe for chromosome 21 would be more useful for detecting the aneuploidy of chromosome 21 than 13/21 centromeric probe.

A comparative trial of Nalador and mechanical stimulation(Metreurynter) in the termination of midtrimester pregnancy / 대한산부인과학회잡지

No abstract available.