scholarly journals Suppressive effect of melatonin on osteoclast function via osteocyte calcitonin

2019 ◽  
Vol 242 (2) ◽  
pp. 13-23 ◽  
Author(s):  
Masaki Nakano ◽  
Mika Ikegame ◽  
Junko Igarashi-Migitaka ◽  
Yusuke Maruyama ◽  
Nobuo Suzuki ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Bone Matrix ◽  
Cathepsin K ◽  
Suppressive Effect ◽  
Melatonin Receptors ◽  
Dependent Manner ◽  
In Ovo ◽  
Expression Levels ◽  
Underlying Mechanisms ◽  
Mrna Expression Levels

Many studies have investigated the actions of melatonin on osteoblasts and osteoclasts. However, the underlying mechanisms, especially regarding osteocyte function, remain largely unknown. Therefore, this study aimed to clarify the underlying mechanisms of melatonin action on bone tissue via osteocyte function. Chick calvariae were employed as a model. In ovo injection of melatonin (5, 50 and 500 µg) dose-dependently decreased the mRNA expression levels of cathepsin K and matrix metalloproteinase 9 (MMP9) in chick calvariae without affecting the expression levels of receptor activator of NF-κB ligand or osteoprotegerin. Surprisingly enough, the expression of calcitonin mRNA in chick calvariae was significantly raised. After 3 days of in vitro treatment of melatonin (10−7 and 10−5 M) on newly hatched chick calvariae, both calcitonin mRNA expression in calvariae and the concentration of calcitonin in cultured medium were augmented in a dose-dependent manner, coincident with the decreased mRNA expression levels of cathepsin K and MMP9. Immunohistochemical analyses revealed expression of melatonin receptors and calcitonin by osteocytes buried in bone matrix. Moreover, the mRNA expression levels of melatonin receptors, calcitonin and sclerostin (a marker of osteocyte), were strongly and positively correlated. In conclusion, we demonstrated the expression of melatonin receptors and calcitonin expression in osteocytes for the first time and suggest a new mechanism underlying the suppressive effect of melatonin on osteoclasts via upregulation of calcitonin secretion by osteocytes.

Imprinting in the schizophrenia candidate gene GABRB2

2011 ◽  
Vol 26 (S2) ◽  
pp. 823-823
Author(s):  
F. Pun ◽  
C. Zhao ◽  
W. Lo ◽  
S. Ng ◽  
S. Tsang ◽  
...  
Keyword(s):  
Candidate Gene ◽  
Mrna Expression ◽  
Association Studies ◽  
Methylation Status ◽  
Dependent Manner ◽  
Expression Levels ◽  
Allele Specific ◽  
Parent Of Origin ◽  
Allele Specific Methylation ◽  
Mrna Expression Levels

Imprinting, characterized by unequal expression of the offspring's genes in a parent-of-origin dependent manner, has been functionally implicated in brain development and in psychiatric disorders. In this study, unambiguous distortion in paternal but not maternal transmission of the disease-associated single-nucleotide polymorphism (SNP) rs6556547 (T/G) clearly indicated the presence of parent-of-origin effect (POE) in the GABAA receptor β2 subunit gene (GABRB2). ‘Flipping’ of allelic mRNA expression in heterozygotes of SNP rs2229944 (C/T) and the observed two-tiered distribution of mRNA expression levels in heterozygotes of the disease-associated SNP rs1816071 (G/A) furnished important support for the occurrence of imprinting at GABRB2. Imprinting in effect introduced heterozygotes from different parents-of-origin endowed with dissimilar mRNA expression capabilities. The deficit of upper-tiered expressions accounted for the lowered mRNA expression levels in the schizophrenic heterozygotes. This pointed to the necessity of differentiating between two kinds of heterozygotes of different parental origins in disease association studies on GABRB2. Bisulfite sequencing revealed hypermethylation in the neighborhood of SNP rs1816071, and methylation differences between controls and schizophrenia patients. Notably, allele-specific methylation was observed at the disease-associated SNPs rs6556547 and rs1816071. These findings raised the possibility that CpG methylation status of these sites could have an impact on the expression of GABRB2 and the risk of schizophrenia. Furthermore, the occurrence of imprinting and allele-specific methylation in the schizophrenia candidate gene GABRB2 was compatible with the epigenetic hypothesis for schizophrenia pathophysiology, thereby calling for the need to explore the role of epigenetic factors in mediating susceptibility to schizophrenia.

scholarly journals Biphasic Roles of Clock Genes and Bone Morphogenetic Proteins in Gonadotropin Expression by Mouse Gonadotrope Cells

2021 ◽  
Vol 22 (20) ◽  
pp. 11186
Author(s):  
Yoshiaki Soejima ◽  
Nahoko Iwata ◽  
Yasuhiro Nakano ◽  
Koichiro Yamamoto ◽  
Atsuhito Suyama ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Early Phase ◽  
Clock Genes ◽  
Late Phase ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Gonadotropin Secretion ◽  
Functional Link ◽  
Expression Levels ◽  
Mrna Expression Levels

Roles of Clock genes and the bone morphogenetic protein (BMP) system in the regulation of gonadotropin secretion by gonadotropin-releasing hormone (GnRH) were investigated using mouse gonadotropin LβT2 cells. It was found that luteinizing hormone (LH)β mRNA expression level in LβT2 cells changed gradually over time, with LHβ expression being suppressed in the early phase up to 12 h and then elevated in the late phase 24 h after GnRH stimulation. In addition, the mRNA expression levels of Clock genes, including Bmal1, Clock, Per2, and Cry1, also showed temporal changes mimicking the pattern of LHβ expression in the presence and absence of GnRH. Notably, the expression levels of Bmal1 and Clock showed strong positive correlations with LHβ mRNA expression levels. Moreover, a functional link of the ERK signaling of mitogen-activated protein kinases (MAPKs) in the suppression of LHβ mRNA expression, as well as Bmal1 and Clock mRNA expression by GnRH at the early phase, was revealed. Inhibition of Bmal1 and Clock expression using siRNA was involved in the reduction in LHβ mRNA levels in the late phase 24 h after GnRH stimulation. Furthermore, in the presence of BMP-6 and -7, late-phase Bmal1 and LHβ mRNA expression after GnRH stimulation was significantly attenuated. Collectively, the results indicated that LH expression in gonadotrope cells exhibits Bmal1/Clock-dependent fluctuations under the influence of GnRH and that the fluctuations are regulated by ERK and BMPs in the early and late stages, respectively, in a phase-dependent manner after GnRH stimulation.

scholarly journals Effect of mir-129 on the Sensitivity Enhancement of Methotrexate and Migration Inhibition in Osteosarcoma Cancer Cells

2021 ◽  
Keyword(s):  
Mrna Expression ◽  
Cancer Cells ◽  
Target Genes ◽  
Osteosarcoma Cells ◽  
Cytotoxic Effects ◽  
Growth And Survival ◽  
Expression Levels ◽  
Cell Death Assay ◽  
Underlying Mechanisms ◽  
Mrna Expression Levels

Background: MicroRNAs have been recently declared to be contributed to the various aspects of osteosarcoma cells, including growth and survival, apoptosis, invasion, and chemoresistance. Objectives: The present study aimed to investigate the potentiating effects of miR-129 on the chemosensitivity of Saose-2 osteosarcoma cells to methotrexate (MTX) and underlying mechanisms. Methods: Saose-2 cells were transfected with miR-129 mimics using Lipofectamine. The cytotoxic effects of miR-129 and MTX on Saose-2 cells were measured using MTT assay. Scratch wound healing assay was used to evaluate cell migration. The apoptosis rate of cancer cells was also measured using ELISA Cell Death Assay and flow cytometry. The mRNA expression levels of target genes were measured using quantitative RT-PCR. Results: miR-129 mimic transfection significantly increased the expression levels of this miRNA in Saose-2 cells (P<0.05). The combination of MTX with miR-129 transfection led to enhanced cytotoxic effects of MTX in lower concentrations. In addition, miR-129 significantly increased MTX-induced apoptosis levels and decreased invasion behavior in Saose-2 cells. The mRNA expression levels of c-Myc, K-Ras, CXCR4, MMP9, and ADAMTS, as main genes involved in chemoresistance and invasion, were downregulated in miR-129 transfected cells. Conclusion: The obtained results revealed the importance of miR-129 in the sensitivity of osteosarcoma cells to MTX and its underlying mechanisms. Therefore, miR-129 might be an appropriate candidate for reversing MTX resistance in osteosarcoma cells.

scholarly journals The role of CXCR3 and its ligands expression in Brucellar spondylitis

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Xin Hu ◽  
Xiaoqian Shang ◽  
Liang Wang ◽  
Jiahui Fan ◽  
Yue Wang ◽  
...  
Keyword(s):  
Protein Expression ◽  
Mrna Expression ◽  
Mononuclear Cells ◽  
Healthy Controls ◽  
Inflammatory Infiltration ◽  
Peripheral Blood Mononuclear ◽  
Expression Levels ◽  
Inflammatory Damage ◽  
Ifn Γ ◽  
Mrna Expression Levels

Abstract Aim Brucellar spondylitis (BS) is one of the most serious complications of brucellosis. CXCR3 is closely related to the severity of disease infection. This research aimed to study the degree of BS inflammatory damage through analyzing the expression levels of CXCR3 and its ligands (CXCL9 and CXCL10) in patients with BS. Methods A total of 29 BS patients and 15 healthy controls were enrolled. Real-Time PCR was used to detect the mRNA expression levels of IFN-γ, CXCR3, CXCL9 and CXCL10 in peripheral blood mononuclear cells (PBMCs) of BS patients and healthy controls. Hematoxylin-Eosin staining was used to show the pathological changes in BS lesion tissues. Immunohistochemistry staining was used to show the protein expression levels of Brucella-Ab, IFN-γ, CXCR3, CXCL9 and CXCL10 in BS lesion tissues. At the same time, ELISA was used to detect the serum levels of IFN-γ, CXCL9 CXCL10 and autoantibodies against CXCR3 in patients with BS. Results In lesion tissue of BS patients, it showed necrosis of cartilage, acute or chronic inflammatory infiltration. Brucella-Ab protein was abundantly expressed in close lesion tissue. And the protein expression levels of IFN-γ, CXCR3 and CXCL10 were highly expressed in close lesion tissue and serum of BS patients. At the same time, the mRNA expression levels of IFN-γ, CXCR3 and CXCL10 in PBMCs of BS patients were significantly higher than those in controls. Conclusion In our research, the expression levels of IFN-γ, CXCR3 and its ligands were significantly higher than those in controls. It suggested that high expression levels of IFN-γ, CXCR3 and its ligands indicated a serious inflammatory damage in patients with BS.

Unilateral labyrinthectomy induced changes on GDNF receptor complex proteins in the rat medial vestibular nuclei

2007 ◽  
Vol 16 (4-5) ◽  
pp. 171-177
Author(s):  
Adrian Lozada ◽  
Kaj Karlstedt ◽  
Pertti Panula ◽  
Antti A. Aarnisalo
Keyword(s):  
Mrna Expression ◽  
Vestibular Nucleus ◽  
Medial Vestibular Nucleus ◽  
Receptor Complex ◽  
Trophic Effect ◽  
Expression Levels ◽  
Protein Levels ◽  
Unilateral Labyrinthectomy ◽  
Ganglion Neurons ◽  
Mrna Expression Levels

In the auditory periphery, GDNF has been shown to have a trophic effect to spiral ganglion neurons, both during development and in adult animals. We have studied the effect of unilateral labyrinthectomy (UL) on protein levels and expression of GDNF multicomponent receptor complex: the ret tyrosine kinase and coreceptor GFRα-1 in the medial vestibular nucleus of the adult rat. GFRα-1 protein levels display an increasing trend in ipsilateral medial vestibular nucleus culminating at 48 h post UL. On the other hand, GFRα-1 mRNA expression levels in ipsi- and contralateral medial vestibular nucleus show a steadily decreasing trend that is significant at 1 week post-lesion. Protein levels for c-Ret isoforms also show an initial bilateral decreasing trend that ceases at 48 h in ipsilateral medial vestibular nucleus but persists on the contralateral side. c-Ret mRNA expression levels show a significant decrease at 4 h post UL followed by another significant decrease 1 week post UL. Our data would suggest that neurotrophins belonging to the GDNF family are involved in this model of post-lesional CNS plasticity.

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