Dieckol isolated from Eisenia bicyclis extract suppresses RANKL-induced osteoclastogenesis in murine RAW 264.7 cells

Objective: To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells. Methods: Murine macrophage RAW 264.7 cells were subjected to dieckol treatment, followed by treatment with receptor activator of nuclear factor kappa-B ligand (RANKL) to induce osteoclastogenesis. Tartrate-resistant acid phosphatase (TRAP) activity was examined using a TRAP activity kit. Western blotting analysis was conducted to examine the level of osteoclast- related factors, including TRAP and calcitonin receptor (CTR), transcriptional factors, including c-Fos, c-Jun, and nuclear factor of activated T cells cytoplasmic 1 (NFATc1), nuclear factor kappa-B (NF-κB), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Immunofluorescence staining was conducted to examine the expression of c-Fos, c-Jun, and NFATc1. Results: Among the four phlorotannin compounds present in Eisenia bicyclis, dieckol significantly hindered osteoclast differentiation and expression of RANKL-induced TRAP and CTR. In addition, dieckol downregulated the expression levels of c-Fos, c-Jun, NFATc1, ERK, and JNK, and suppressed NF-κB signaling. Conclusions: Dieckol can suppress RANKL-induced osteoclastogenesis. Therefore, it has therapeutic potential in treating osteoclastogenesis- associated diseases.

Study on expression and change of CRLR, CGRP-RCP in venous blood of New Zealand rabbit with allergic rhinitis / 重庆医学

Objective To observe the expressions and change of calcitonin receptor-like receptor(CRLR) and calcitonin generelated peptide receptor component protein(CGRP-RCP)in venous blood of New Zealand rabbit with allergic rhinitis and to analyze its effective mechanism.Methods Twenty-four New Zealand rabbits were divided into the normal control group(A) and allergic rhinitis group(B).Ovalbumin was used to immunize New Zealand rabbits and conduct the nasal cavity stimulation for preparing allergic rhinitis model.The rabbit behavior change was observed in the two groups.The turbinate and nasal septum mucosa were taken for preparing HE sections.The pathologic change of nasal mucosa was observed.The venous blood was collected for detecting CRLR and CGRP-RCP levels change by ELISA.Results The behavior scores showed that the behavior score on 1-5 d after nasal cavity stimulation had statistical difference between the two groups(P＜0.05).The HE staining displayed that the nasal cavity mucosa and mesenchyma had slightly edema with blood vessels mild hyperplasia and congestion,the inflammatory cells infiltration was unobvious,and had little nasal secretions.The group B had obvious interstitial edema,vascular hyperplasia,congestion and a large number of eosinophils and other inflammatory cells infiltration.The CRLR and CGRP-RCP levels in the group B were significantly increased compared with the group A(t=5.143,10.595,P＜0.05).Conclusion CRLR and CGRP-RCP may play an important effect in pathogenesis of allergic rhinitis.

Study on expression and change of CRLR, CGRP-RCP in venous blood of New Zealand rabbit with allergic rhinitis / 重庆医学

Objective To observe the expressions and change of calcitonin receptor-like receptor(CRLR) and calcitonin generelated peptide receptor component protein(CGRP-RCP)in venous blood of New Zealand rabbit with allergic rhinitis and to analyze its effective mechanism.Methods Twenty-four New Zealand rabbits were divided into the normal control group(A) and allergic rhinitis group(B).Ovalbumin was used to immunize New Zealand rabbits and conduct the nasal cavity stimulation for preparing allergic rhinitis model.The rabbit behavior change was observed in the two groups.The turbinate and nasal septum mucosa were taken for preparing HE sections.The pathologic change of nasal mucosa was observed.The venous blood was collected for detecting CRLR and CGRP-RCP levels change by ELISA.Results The behavior scores showed that the behavior score on 1-5 d after nasal cavity stimulation had statistical difference between the two groups(P＜0.05).The HE staining displayed that the nasal cavity mucosa and mesenchyma had slightly edema with blood vessels mild hyperplasia and congestion,the inflammatory cells infiltration was unobvious,and had little nasal secretions.The group B had obvious interstitial edema,vascular hyperplasia,congestion and a large number of eosinophils and other inflammatory cells infiltration.The CRLR and CGRP-RCP levels in the group B were significantly increased compared with the group A(t=5.143,10.595,P＜0.05).Conclusion CRLR and CGRP-RCP may play an important effect in pathogenesis of allergic rhinitis.

Association of the single nucleotide polymorphisms in the calcitonin receptor-like receptor gene with primary angle closure in a Han Chinese population / 国际眼科杂志(Guoji Yanke Zazhi)

?AIM: To study the association of the single nucleotide polymorphism ( SNP) rs1157699 in the calcitonin receptor-like receptor ( CRLR ) gene with primary angle closure ( PAC) in a Han Chinese population.?METHODS: All samples, involved 232 PAC cases and 306 controls, were obtained from an epidemiologic survey conducted in Funing, Jiangsu Province, China. Genotyping were carried out by TaqMan-MGB probe using the real time quantitative polymerase chain reaction system to study the relationship between SNP of rs1157699 in CRLR gene and PAC.?RESULTS: The prevalence of CRLRrs1157699 genotype was 67.4%, 30.0%, 2.6% for CC, CT, TT in cases, and 71.3%, 27.0%, 1.7% in controls respectively.There was no difference between the two groups in the distribution of genotype and allele frequencies of rs1157699 (P>0.05).?CONCLUSION:Our results do not support a significant role for rs1157699 in CRLR with PAC.

Association of Calcitonin Receptor 1340 C>T Polymorphism with Periodontitis Susceptibility.

Background: Periodontitis is a common multifactorial oral disease and a major cause of tooth loss among adults. The present study was aimed to investigate the role of calcitonin receptor (CTR) gene polymorphism in the causation of periodontitis. Materials and Methods: A total of 112 subjects comprising of 62 patients and 50 controls were enrolled and recruited from various dental clinics in and around Hyderabad, India. Two milliliter of blood sample was collected from all the subjects. Following extraction of DNA, genotyping for CTR 1340 C>T was performed by PCR-RFLP. Results: The frequency of CC, CT and TT genotypes in patients was 45%, 42% and 13% while in controls it was 56%, 32% and 12%. The frequency of C and T allele was 0.66 and 0.34 in patients whereas it was 0.72 and 0.28 in controls. The genotype and allele frequencies did not vary between the groups. The genotype frequencies among male and female sub-types revealed a statistically significant difference in female subgroup. The CT genotype and T allele revealed an OR value of 5.62 and 2.40 respectively. Conclusion: Our study revealed a significant association of this SNP with periodontitis only in females. It also highlights the predisposing role of CT genotype and T allele in the causation of periodontitis. However, replicative studies on the influence of this polymorphism in different ethnic groups may identify the potentiality of this SNP towards periodontitis.

Pharmacological characterization of the relaxant effect induced by adrenomedullin in rat cavernosal smooth muscle

The aim of the present study was to determine the mechanisms underlying the relaxant effect of adrenomedullin (AM) in rat cavernosal smooth muscle (CSM) and the expression of AM system components in this tissue. Functional assays using standard muscle bath procedures were performed in CSM isolated from male Wistar rats. Protein and mRNA levels of pre-pro-AM, calcitonin receptor-like receptor (CRLR), and Subtypes 1, 2 and 3 of the receptor activity-modifying protein (RAMP) family were assessed by Western immunoblotting and quantitative real-time polymerase chain reaction, respectively. Nitrate and 6-keto-prostaglandin F1α (6-keto-PGF1α; a stable product of prostacyclin) levels were determined using commercially available kits. Protein and mRNA of AM, CRLR, and RAMP 1, -2, and -3 were detected in rat CSM. Immunohistochemical assays demonstrated that AM and CRLR were expressed in rat CSM. AM relaxed CSM strips in a concentration-dependent manner. AM22-52, a selective antagonist for AM receptors, reduced the relaxation induced by AM. Conversely, CGRP8-37, a selective antagonist for calcitonin gene-related peptide receptors, did not affect AM-induced relaxation. Preincubation of CSM strips with NG-nitro-L-arginine-methyl-ester (L-NAME, nitric oxide synthase inhibitor), 1H-(1,2,4)oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, quanylyl cyclase inhibitor), Rp-8-Br-PET-cGMPS (cGMP-dependent protein kinase inhibitor), SC560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethyl pyrazole, selective cyclooxygenase-1 inhibitor], and 4-aminopyridine (voltage-dependent K+ channel blocker) reduced AM-induced relaxation. On the other hand, 7-nitroindazole (selective neuronal nitric oxide synthase inhibitor), wortmannin (phosphatidylinositol 3-kinase inhibitor), H89 (protein kinase A inhibitor), SQ22536 [9-(tetrahydro-2-furanyl)-9H-purin-6-amine, adenylate cyclase inhibitor], glibenclamide (selective blocker of ATP-sensitive K+ channels), and apamin (Ca2+-activated channel blocker) did not affect AM-induced relaxation. AM increased nitrate levels and 6-keto-PGF1α in rat CSM. The major new contribution of this research is that it demonstrated expression of AM and its receptor in rat CSM. Moreover, we provided evidence that AM-induced relaxation in this tissue is mediated by AM receptors by a mechanism that involves the nitric oxide-cGMP pathway, a vasodilator prostanoid, and the opening of voltage-dependent K+ channels.

Interaction of calcitonin receptor gene polymorphisms and environmental factors in the population lived in coal-burning-borne endemic fluorosis areas in Chongqing / 中华地方病学杂志

Objective To explore the interaction of calcitonin receptor (CTR) gene polymorphisms and environmental factors in the population lived in coal-burning-borne endemic fluorosis areas in Chongqing.Methods A 1 ∶ 1 case-control study was carried out and Duping Township of Wushan County and Xinglong Township of Fengjie County of Chongqing were chosen as the endemic fluorosis areas.The observation subjects were divided into case group 121 cases and internal control group 130 cases.The Alu I polymorphism in the CTR gene was genotyped using the PCR-RFLP procedure.Logistic regression model was used to analyze the environment and genetic factors,and the interaction between genes and environment was determined according to interaction indicators.Results The rate of CC genotype in case group was lower than that of the control group [60.33％ (73/121) vs.74.62％ (97/130)],while the TT genotype was higher than that of the control group[9.09％ (11/21) vs.3.85％(5/130)].Significant differences in Alu I genotypes were observed between groups(x2 =6.57,P =0.037 ＜ 0.05; 95％CI:0.029-0.036).Allele frequencies of CTR genotypes differed significantly between groups(x2 =7.67,P =0.006 ＜ 0.01 ; OR =0.53,95 ％ CI:0.338-0.834).Urinary fluoride level (≥ 1 mg/L) was demonstrated to be a risk factor of fluorosis(OR =1.814,P =0.041 ＜ 0.05).There was a positive interaction(OR =5.530,γ =2.457) between CT + TT genotypes in CTR and the fluorosis environment of the people (urinary fluoride level ≥ 1 mg/L).Conclusions There is a certain type of interaction between CTR gene C/T polymorphism and environmental fluorine content (urinary fluoride ≥ 1 mg/L) in Chongqing population lived in coal-burning-borne fluorosis areas,and the onset of fluorosis is the result of interaction between heredity and environment.

Research progress of the pathophysiological role of receptor activity modifying proteins / 国际生物医学工程杂志

Receptor activity modifying proteins (RAMPs) is a kind protein with transmembrane functionality.RAMPs can interact with TypeⅡ G protein coupled receptors (GPCRs) such as calcitonin gene-related peptide receptor (CGRPR),calcitonin receptor (CTR) and calcitonin receptor-like receptor (CRLR),to form a stable heterodimer expression on the cell membrane.Different RAMPs can combine with CRLR or CTR to produce different receptor phenotypes with ligand-specific affinity and thus can decide biological effect of the receptors.In addition,RAMPs can also interact with other GPCRs,which promise broader application in function regulation of G-proteincoupled receptor of RAMPs'.RAMPs' regulation of GPCRs depends on its molecular basis.Our studies of RAMPs provides a new perspective to further researches on GPCRs functionality and CGRP signal transduction.

Effects of continuous intermedin infusion on blood pressure and hemodynamic function in spontaneously hypertensive rats / 老年心脏病学杂志（英文版）

Objective To examine the effects of exogenously administered intermedin (IMD,adrenomedullin-2) on arterial blood pressure,cardiac function and the cardiovascular IMD receptor system in spontaneously hypertensive rats (SHRs) as well as to investigate the associated mechanisms.Methods Thirteen week-old male rats were divided in Wistar Kyoto (WKY) group (n =12),SHR group (n =12),IMD group (SHRs infused with IMD 1-47 500 ng/kg per hour,n =12),and ADM group (SHRs infused with adrenomedullin 500 ng/kg per hour,n =12).Results A two-week continuous administration of low dose IMD 1-47 via mini-osmotic pumps markedly reduced blood pressure,the maximal rates of increase and decrease of left-ventricle pressure development (LV ± dp/dtmax),left ventricular systolic pressure and heart rate in SHRs.Furthermore,IMD also inhibited protein over-expression of cardiovascular IMD receptors,myocardial Receptor Activity-Modifying Proteins (RAMP1 and RAMP2),aortic RAMP1,RAMP2,RAMP3,and calcitonin receptor-like receptor (CRLR);suppressed up-regulation of aortic RAMP1,RAMP2,RAMP3 and CRLR gene expression; and markedly elevated the mRNA abundance of myocardial atrial natriuretic peptide (ANP) and myocardial brain natriuretic peptide (BNP).Additionally,IMD 1-47 administration in SHRs increased aortic cAMP concentration and reduced myocardial cAMP concentration.Conclusion These findings support the speculation that IMD,as a cardiovascular active peptide,is involved in blood pressure reduction and cardiac function amelioration during hypertension.The mechanism underlying this effect may involve IMD binding of a receptor complex formed by RAMPs and CRLR,and consequential regulation of cAMP levels and other cardiovascular active factors,such as ANP and BNP.

Effect of calcitonin on analgesia and expression of calcitonin receptor in periaqueductal gray / 中华内分泌代谢杂志

Objective To investigate the analgesic effect of salmon calcitonin(sCT)and its effect on expression of calcitonin receptor(CT-R)in periaqueductal gray(PAG). Methods Rat models of neuropathic pain were prepared by chronic constriction injury(CCI). Thermal withdrawal latency(TWL)and mechanical nociceptive threshold(MNT)were measured using hot plate test and yon Frey monofilaments test. The distribution of CT-R in PAG was detected by immunohistochemical method. CT-R protein was quantitatively determined by western blotting. Fourty male SD rats were randomized into 5 groups: normal group, sham-CCI group, CCI group, CCI plussubcutaneous sCT group, and CCI plus microinjection of sCT into PAG group. Results TWL, MNT, andexpression of CT-R in PAG showed no difference between normal group and sham-CCI group(P＞0. 05). TWL and MNT in CCI group were significantly lower than those in normal group(P＜0.05), and expression of CT-R in CCI group was significantly higher than that in normal group(P＜0.05). TWL, MNT and expression of CT-R in CCI rats increased significantly after sCT therapy(P＜0. 05), and the effect was more marked in PAG injection group than subcutaneous injection group(P＜0.05). Conclusions sCT raises the pain threshold and increase the expression of CT-R in PAG of CCI rats, while PAG injection showed more marked effect than subcutaneous injection.

Study of the relationship between gene polymorphism of vitamin D receptor, calcitonin receptor and bone mineral density of the Han nationality woman in Hebei / 中国康复理论与实践

@#ObjectiveTo study the relationship between vitamin D receptor (VDR) gene polymorphism and calcitonin receptor (CTR) gene polymorphism, and bone mineral density (BMD) of the Han nationality woman in Hebei, explore the pathogenesis of osteoporosis (OP) at the gene level.MethodsPolymorphisms of VDR gene and CTR gene were analyzed by restriction fragment length polymorphisms (RFLPs) in 60 Han nationality women in Hebei.ResultsBb genetype of VDR had lower BMD values at all sites which were measured compared with bb genetype (P<0.05); CC genetype of CTR had tendency for lower BMD values at the L1～L4 compared with CT genetype (0.05<P<0.1); BMD value of CCBb genetype was the lowest.ConclusionBb genetype of VDR has a relationship with lower BMD. CCBb genetype can act as a heredity mark of OP in Chinese Han nationality woman.

The relationship between calcitonin receptor gene AluI polymorphism, bone mineral density and bone responsiveness to hormone replacement therapy in postmenopausal Korean women / 대한산부인과학회지

OBJECTIVE: To evaluate the relationship between the calcitonin receptor (CTR) gene AluI polymorphism, serum calcitonin levels, bone mineral density (BMD) and bone responsiveness to hormone replacement therapy (HRT). METHODS: The CTR AluI polymorphism were determined by restriction fragment length polymorphism (RFLP) in 433 postmenopausal Korean women. Among these women, 306 women received sequential HRT for 1 year. Serum bone alkaline phosphatase, CrossLaps, osteocalcin and calcitonin levels were measured by immunoassay and BMD at the lumbar spine and proximal femur by dual energy X-ray absorptiometry before and after HRT of 1 year. RESULTS: The CTR genotype frequencies were 81.3% for CC, 17.5% for CT, and 1.2% for TT. No significant differences in BMD at the lumbar spine and proximal femur and their annual percentage changes after HRT were noted among CTR genotypes. There were no significant differences in the levels of calcitonin or bone turnover markers and their 6 month percentage changes after HRT among CTR genotypes. The CTR genotypes were not distributed differently between HRT-responders and HRT-nonresponders (women who lose more than 3% of bone mass per year) or between women with normal BMD and women with low bone mass. CONCLUSION: The CTR AluI polymorphism is not associated with BMD and bone responsiveness to HRT in Korean women.

Protect effect of Intermedin_(1-53) on isoproterenol-induced ischemic injury in rats heart / 中国药理学通报

Aim Observe the effects of IMD_ 1-53 on acute myocardial injury induced by isoproterenol (ISO). Methods Myocardial ischemia injury in rats was induced by subcutaneous injection with ISO(50 mg?kg -1?d -1, 2days ), and the therapeutic effect of IMD_ 1-53 was observed. Cardiac function was measured. Myocardial cAMP content was determined by radioimmunoassay (RIA). The gene expression of calcitonin receptor-like receptor (CL) and receptor-activity-modifying protein (RAMP1), RAMP2 and RAMP3 in ventricular was determined by semi-quantitative RT-PCR analysis. IMD receptors in cardiac sarcolemmal membrane fractions were assayed [ 125I]-IMD binding studies. Results ISO-treated rats showed lower maximal rate of increase and decrease of left-ventricle pressure development (?LVdp/dt_ max) and higher left-ventricle end-diastolic pressure (LVEDP; all P