963 resultados para Receptor, ErbB-3
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Objective. To evaluate the antiinflammatory effects of RC-3095 in 2 experimental models of arthritis, collagen-induced arthritis (CIA) and antigen-induced arthritis (AIA), and to determine the mechanisms of action involved. Methods. RC-3095 was administered daily to mice with CIA and mice with AIA, after induction of disease with methylated bovine serum albumin. Disease incidence and severity were assessed using a clinical index and evaluation of histologic features, respectively. In mice with CIA, gastrin-releasing peptide receptor (GRPR) was detected by immunohistochemical analysis, while in mice with AIA, migration of neutrophils, presence of glycosaminoglycans, and lymphocyte proliferation, determined using the MTT assay, were assessed. Expression of cytokines interleukin-17 (IL-17), IL-1 beta, and tumor necrosis factor alpha (TNF alpha) was evaluated in all mouse knees using enzyme-linked immunosorbent assay. Treg cell production was assessed by flow cytometry in the joints of mice with AIA. Results. In mice with AIA, administration of RC-3095 reduced neutrophil migration, mechanical hypernociception, and proteoglycan loss. These findings were associated with inhibition of the levels of all 3 proinflammatory cytokines, decreased lymphocyte proliferation, and increased Treg cell numbers. In the CIA model, treatment with RC-3095 led to a significant reduction in arthritis clinical scores and the severity of disease determined histologically. Synovial inflammation, synovial hyperplasia, pannus formation, and extensive erosive changes were all dramatically reduced in the arthritic mice treated with RC-3095. Furthermore, arthritic mice treated with RC-3095 showed a significant reduction in the concentrations of IL-17, IL-1 beta, and TNF alpha, and showed a diminished expression of GRPR. Conclusion. These findings suggest that the GRP pathway has a significant role in chronic arthritis, and its inhibition can be explored as a possible therapeutic strategy in rheumatoid arthritis.
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The endocannabinoid anandamide is a possible agonist at the Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel, in addition to its agonist activity at cannabinoid type 1 (CB1) receptor. In the midbrain dorsolateral periaqueductal gray (dlPAC) our previous data showed that CB1 activation induces anxiolytic-like effects. However, the rote of TRPV1 has remained unclear. Thus, in the present study we tested the hypothesis that this channel would contribute to the modulation of anxiety-like behaviour in the dlPAG. Mate Wistar rats received local injections of the TRPV1 antagonist capsazepine (10-60 nmol) and were submitted to the elevated plus-maze (EPM) and to the Vogel test. In addition, animals received local injections of capsaicin (0.01-1nmol), a TRPV1 agonist, and were tested in the same models. In accordance with our hypothesis, capsazepine produced anxiolytic-like effects both in the EPM and in the Vogel test. Capsaicin mimicked these results, which might be attributed to its ability to quickly desensitize the channel. Altogether, our data suggest that, while CB1 receptors seem to inhibit aversive responses in the dlPAG, TRPV1 could facilitate them. Thus, CB1 and TRPV1 may have opposite functions in modulating anxiety-like behaviour in this region. (C) 2008 Elsevier B.V. and ECNP. All rights reserved.
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Lipopolysaccharide (LPS) stimulates cytoplasmic accumulation of pro-interleukin (IL)-1 beta. Activation of P2X(7) receptors stimulates conversion of pro-IL-1 beta into mature IL-1 beta, which is then secreted. Because both LPS (in vivo) and IL-1 beta (in vitro) decrease vascular reactivity to contractile agents, we hypothesized the following: 1) P2X(7) receptor activation contributes to LPS-induced vascular hyporeactivity, and 2) IL-1 beta mediates this change. Thoracic aortas were obtained from 12-week-old male C57BL/6 mice. The aortic rings were incubated for 24 h in Dulbecco`s modified Eagle`s medium, LPS, benzoylbenzoyl-ATP (BzATP; P2X(7) receptor agonist), LPS plus BzATP, oxidized ATP (oATP; P2X(7) receptor antagonist), or oATP plus LPS plus BzATP. After the treatment, the rings were either mounted in a myograph for evaluation of contractile activity or homogenized for IL-1 beta and inducible nitric-oxide synthase (iNOS) protein measurement. In endothelium-intact aortic rings, phenylephrine (PE)-induced contractions were not altered by incubation with LPS or BzATP, but they significantly decreased in aortic rings incubated with LPS plus BzATP. Treatment with oATP or IL-1ra (IL-1 beta receptor antagonist) reversed LPS plus BzATP-induced hyporeactivity to PE. In the presence of N(G)-nitro-L-arginine methyl ester or N-([3-(aminomethyl) phenyl] methyl) ethanimidamide (selective iNOS inhibitor), the vascular hyporeactivity induced by LPS plus BzATP on PE responses was not observed. BzATP augmented LPS-induced IL-1 beta release and iNOS protein expression, and these effects were also inhibited by oATP. Moreover, incubation of endothelium-intact aortic rings with IL-1 beta induced iNOS protein expression. Thus, activation of P2X 7 receptor amplifies LPS-induced hyporeactivity in mouse endothelium-intact aorta, which is associated with IL-1 beta-mediated release of nitric oxide by iNOS.
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The medial amygdaloid nucleus (MeA) is involved in the modulation of physiological and behavioral processes, as well as regulation of the autonomic nervous system. Moreover, MeA electrical stimulation evokes cardiovascular responses. Thus, as noradrenergic receptors are present in this structure, the present study tested the effects of local noradrenaline (NA) microinjection into the MeA on cardiovascular responses in conscious rats. Moreover, we describe the types of adrenoceptor involved and the peripheral mechanisms involved in the cardiovascular responses. Increasing doses of NA (3, 9, 27 or 45 nmol/100 nL) microinjected into the MeA of conscious rats caused dose-related pressor and bradycardic responses. The NA cardiovascular effects were abolished by local pretreatment of the MeA with 10 nmol/100 nL of the specific alpha(2)-receptor antagonist RX821002, but were not affected by local pretreatment with 10 nmol/100 nL of the specific alpha(1)-receptor antagonist WB4101. The magnitude of pressor response evoked by NA microinjected into the MeA was potentiated by intravenous pretreatment with the ganglion blocker pentolinium (5 mg/kg), and blocked by intravenous pretreatment with the selective V(1)-vasopressin antagonist dTyr(CH(2))(5)(Me)AVP (50 mu g/kg). In conclusion, our results show that microinjection of NA into the MeA of conscious rats activates local alpha(2)-adrenoceptors, evoking pressor and bradycardic responses, which are mediated by vasopressin release.
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Granulocyte-colony stimulating factor (G-CSF) is a current pharmacological approach to increase peripheral neutrophil counts after anti-tumor therapies. Pain is most relevant side effect of G-CSF in healthy volunteers and cancer patients. Therefore, the mechanisms of G-CSF-induced hyperalgesia were investigated focusing on the role of spinal mitogen-activated protein (MAP) kinases ERK (extracellular signal-regulated kinase). JNK (Jun N-terminal Kinase) and p38, and PI(3)K (phosphatidylinositol 3-kinase). G-CSF induced dose (30-300 ng/paw)-dependent mechanical hyperalgesia, which was inhibited by local post-treatment with morphine. This effect of morphine was reversed by naloxone (opioid receptor antagonist). Furthermore, G-CSF-induced hyperalgesia was inhibited in a dose-dependent manner by intrathecal pre-treatment with ERK (PD98059), JNK (SB600125), p38 (SB202190) or PI(3)K (wortmanin) inhibitors. The co-treatment with MAP kinase and PI(3)K inhibitors, at doses that were ineffective as single treatment, significantly inhibited G-CSF-induced hyperalgesia. Concluding, in addition to systemic opioids, peripheral opioids as well as spinal treatment with MAP kinases and PI(3)K inhibitors also reduce G-CSF-induced pain. (C) 2011 Elsevier Inc. All rights reserved.
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The 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) is an endogenous ligand of peroxisome proliferator-activated receptors gamma (PPAR-gamma) and is now recognized as a potent anti-inflammatory mediator. However, information regarding the influence of 15d-PGJ(2) on inflammatory pain is still unknown. In this study, we evaluated the effect of 15d-PGJ(2) upon inflammatory hypernociception and the mechanisms involved in this effect. We observed that intraplantar administration of 15d-PGJ(2) (30-300 ng/paw) inhibits the mechanical hypernociception induced by both carrageenan (100 mu g/paw) and the directly acting hypernociceptive mediator, prostaglandin E-2 (PGE(2)). Moreover, 15d-PGJ(2) [100 ng/temporomandibular joint (TMJ)] inhibits formalininduced TMJ hypernociception. On the other hand, the direct administration of 15d-PGJ(2) into the dorsal root ganglion was ineffective in blocking PGE(2)- induced hypernociception. In addition, the 15d-PGJ(2) antinociceptive effect was enhanced by the increase of macrophage population in paw tissue due to local injection of thioglycollate, suggesting the involvement of these cells on the 15d-PGJ(2)-antinociceptive effect. Moreover, the antinociceptive effect of 15d-PGJ(2) was also blocked by naloxone and by the PPAR-gamma antagonist 2-chloro-5-nitro-N-phenylbenzamide (GW9662), suggesting the involvement of peripheral opioids and PPAR-gamma receptor in the process. Similar to opioids, the 15d-PGJ(2) antinociceptive action depends on the nitric oxide/cGMP/protein kinase G (PKG)/K-ATP(+) channel pathway because it was prevented by the pretreatment with the inhibitors of nitric-oxide synthase (N-G-monomethyl-L-arginine acetate), guanylate cyclase] 1H-(1,2,4)-oxadiazolo(4,2-alpha) quinoxalin-1- one[, PKG [indolo[2,3-a]pyrrolo[3,4-c]carbazole aglycone (KT5823)], or with the ATP-sensitive potassium channel blocker glibenclamide. Taken together, these results demonstrate for the first time that 15d-PGJ(2) inhibits inflammatory hypernociception via PPAR-gamma activation. This effect seems to be dependent on endogenous opioids and local macrophages.
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Rationale Sepsis is a leading cause of death in the intensive care unit, characterized by a systemic inflammatory response (SIRS) and bacterial infection, which can often induce multiorgan damage and failure. Leukocyte recruitment, required to limit bacterial spread, depends on phosphoinositide-3 kinase gamma (PI3K gamma) signaling in vitro; however, the role of this enzyme in polymicrobial sepsis has remained unclear. Objectives: This study aimed to determine the specific role of the kinase activity of PI3K gamma in the pathogenesis of sepsis and multiorgan damage. Methods. PI3K gamma wild-type, knockout, and kinase-dead mice were exposed to cecal ligation and perforation induced sepsis and assessed for survival; pulmonary, hepatic, and cardiovascular damage; coagulation derangements; systemic inflammation; bacterial spread; and neutrophil recruitment. Additionally, wild-type mice were treated either before or after the onset of sepsis with a PI3K gamma inhibitor and assessed for survival, neutrophil recruitment, and bacterial spread. Measurements and Main Results: Both genetic and pharmaceutical PI3K gamma kinase inhibition significantly improved survival, reduced multiorgan damage, and limited bacterial decompartmentalization, while modestly affecting SIRS. Protection resulted from both neutrophil-independent mechanisms, involving improved cardiovascular function, and neutrophil-dependent mechanisms, through reduced susceptibility to neutrophil migration failure during severe sepsis by maintaining neutrophil surface expression of the chemokine receptor, CXCR2. Furthermore, PI3K gamma pharmacological inhibition significantly decreased mortality and improved neutrophil migration and bacterial control, even when administered during established septic shock. Conclusions: This study establishes PI3K gamma as a key molecule in the pathogenesis of septic infection and the transition from SIRS to organ damage and identifies it as a novel possible therapeutic target.
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Dysfunction in the hypothalamic GABAergic system has been implicated in panic syndrome in humans. Furthermore, several studies have implicated the hypothalamus in the elaboration of pain modulation. Panic-prone states are able to be experimentally induced in laboratory animals to study this phenomenon. The aim of the present work was to investigate the involvement of medial hypothalamic nuclei in the organization of panic-like behaviour and the innate fear-induced oscillations of nociceptive thresholds. The blockade of GABA(A) receptors in the neuronal substrates of the ventromedial. or dorsomedial hypothalamus was followed by elaborated defensive panic-like reactions. Moreover, innate fear-induced antinociception was consistently elicited after the escape behaviour. The escape responses organized by the dorsomedial and ventromedial hypothalamic nuclei were characteristically more elaborated, and a remarkable exploratory behaviour was recorded during GABA(A) receptor blockade in the medial hypothalamus. The motor characteristic of the elaborated defensive escape behaviour and the patterns of defensive alertness and defensive immobility induced by microinjection of the bicuculline either into the dorsomedial. or into the ventromedial hypothalamus were very similar. This was followed by the same pattern of innate fear-induced antinociceptive response that lasted approximately 40 min after the elaborated defensive escape reaction in both cases. These findings suggest that dysfunction of the GABA-mediated neuronal system in the medial hypothalamus causes panic-like responses in laboratory animals, and that the elaborated escape behaviour organized in both dorsomedial and ventromedial hypothalamic nuclei are followed by significant innate-fear-induced antinociception. Our findings indicate that the GABA(A) receptor of dorsomedial and ventromedial hypothalamic nuclei are critically involved in the modulation of panic-like behaviour. (C) 2009 Elsevier B.V. All rights reserved.
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Rationale Hyperaldosteronism, important in hypertension, is associated with electrolyte alterations, including hypomagnesemia, through unknown mechanisms. Objective To test whether aldosterone influences renal Mg(2+) transporters, (transient receptor potential melastatin (TRPM) 6, TRPM7, paracellin-1) leading to hypomagnesemia, hypertension and target organ damage and whether in a background of magnesium deficiency, this is exaggerated. Methods and results Aldosterone effects in mice selectively bred for high-normal (MgH) or low (MgL) intracellular Mg(2+) were studied. Male MgH and MgL mice received aldosterone (350 mu g/kg per day, 3 weeks). SBP was elevated in MgL. Aldosterone increased blood pressure and albuminuria and increased urinary Mg(2+) concentration in MgH and MgL, with greater effects in MgL. Activity of renal TRPM6 and TRPM7 was lower in vehicle-treated MgL than MgH. Aldosterone increased activity of TRPM6 in MgH and inhibited activity in MgL. TRPM7 and paracellin-1 were unaffected by aldosterone. Aldosterone-induced albuminuria in MgL was associated with increased renal fibrosis, increased oxidative stress, activation of mitogen-activated protein kinases and nuclear factor-NF-kappa B and podocyte injury. Mg(2+) supplementation (0.75% Mg(2+)) in aldosterone-treated MgL normalized plasma Mg(2+), increased TRPM6 activity and ameliorated hypertension and renal injury. Hence, in a model of inherited hypomagnesemia, TRPM6 and TRPM7, but not paracellin-1, are downregulated. Aldosterone further decreased TRPM6 activity in hypomagnesemic mice, a phenomenon associated with hypertension and kidney damage. Such effects were prevented by Mg(2+) supplementation. Conclusion Amplified target organ damage in aldosterone-induced hypertension in hypomagnesemic conditions is associated with dysfunctional Mg(2+)-sensitive renal TRPM6 channels. Novel mechanisms for renal effects of aldosterone and insights into putative beneficial actions of Mg(2+), particularly in hyperaldosteronism, are identified. J Hypertens 29: 1400-1410 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.
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1. The present study evaluated changes in autonomic control of the cardiovascular system in conscious rats following blockade of endothelin (ET) receptors with bosentan. 2. Rats were treated with bosentan or vehicle (5% gum arabic) for 7 days by gavage. 3. Baseline heart rate (HR) was higher in the bosentan-treated group compared with the control group (418 +/- 5 vs 357 +/- 4 b.p.m., respectively; P < 0.001). This baseline tachycardia was associated with a lower baroreflex sensitivity of the bradycardiac and tachycardiac responses in the bosentan-treated group compared with the control group. Sequential blockade of the parasympathetic and sympathetic autonomic nervous system with methylatropine and propranolol showed a higher intrinsic HR in the bosentan-treated group compared with the control group (411 +/- 5 vs 381 +/- 4 b.p.m., respectively; P < 0.05). This was accompanied by a higher cardiac sympathetic tone (31 +/- 1 vs 13 +/- 1%, respectively; P < 0.01) and a lower vagal parasympathetic tone (69 +/- 2 vs 87 +/- 2%, respectively; P < 0.01) in the bosentan-treated group compared with the control group. Variance and high-frequency oscillations of pulse interval (PI) variability in absolute and normalized units were lower in the bosentan-treated group than in the control group. Conversely, low-frequency (LF) oscillations of PI variability in absolute and normalized units, as well as variance and LF oscillations of systolic arterial pressure variability, were greater in the bosentan-treated group than the control group. 4. Overall, the data indicate an increased cardiac sympathetic drive, as well as lower vagal parasympathetic activity and baroreflex sensitivity, in conscious rats after chronic blockade of ET receptors with bosentan.
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Objective: To investigate the expression of capsaicin receptor [transient receptor potential vanilloid type-1 (TRPV1)] in the peritoneum of women with chronic pelvic pain (CPP). Methods: A case-control study was conducted on 25 women with CPP and 10 controls. Samples of the rectouterine excavation (2 cm 2) were obtained by laparoscopy, fixed in 4% formaldehyde, and underwent immunohistochemistry analysis using rabbit anti-TRPV1 (1:400) polyclonal antibodies and anti-protein gene product 9.5 (PGP 9.5) (1:2000) as a neuronal marker. Ten sequential images of high magnification fields ( x 40) were captured from each slide and the area identified with the antibody was calculated with Kontron V2.0 software. Results: Immunoreactivity to TRPV1 was sparsely detected in the nervous tissue and epithelium of endometriotic lesions. The percent area of immunoreactivity for TRPV1 [expressed as median (range)] was greater in specimens from women with CPP, 1.02% (0.54 to 2.93), than from women without the disease, 0.14% (0.07 to 1.12) (P<0.0001). This greater expression was not secondary to an increase in neuronal fibers because there was also a significant difference in the percent area TRPV1:PGP 9.5 ratio between women with CPP, 1.18 (0.26 to 4.63), and controls, 0.15 (0.06 to 0.95) (P = 0.0003). Discussion: TRPV1 may play an important role in the maintenance and perpetuation of symptoms in women with CPP. In view of the immunoreactivity detected for TRPV1, the endometriotic lesion may have the ability to interfere with nociception or with the inflammatory peritoneal environment in women with CPP. Further Studies are needed to elucidate the participation of TRPV1 in CPP and its association with endometriosis.
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Context: Type 1 pseudohypoaldosteronism (PHA1), a primary form of mineralocorticoid resistance, isdueto inactivating mutations of the NR3C2 gene, coding for the mineralocorticoid receptor (MR). Objective: The objective of the study was to assess whether different NR3C2 mutations have distinct effects on the pattern of MR-dependent transcriptional regulation of aldosterone-regulated genes. Design and Methods: Four MR mutations affecting residues in the ligand binding domain, identified in families with PHA1, were tested. MR proteins generated by site-directed mutagenesis were analyzed for their binding to aldosterone and were transiently transfected into renal cells to explore the functional effects on the transcriptional activity of the receptors by cis-trans-cotrans-activation assays and by measuring the induction of endogenous gene transcription. Results: Binding assays showed very low or absent aldosterone binding for mutants MR(877Pro), MR(848Pro), and MR(947stop) and decreased affinity for aldosterone of MR(843Pro). Compared with wildtype MR, the mutations p.Leu843Pro and p.Leu877Pro displayed half-maximal aldosterone-dependent transactivation of reporter genes driven by mouse mammary tumor virus or glucocorticoid response element-2 dependent promoters, whereas MR(848Pro) and MR(947stop) nearly or completely lost transcriptional activity. Although MR(848Pro) and MR(947stop) were also incapable of inducing aldosterone-dependent gene expression ofendogenoussgk1, GILZ, NDRG2, and SCNN1A, MR(843Pro) retained complete transcriptional activity on sgk1 and GILZ gene expression, and MR(877Pro) negatively affected the expression of sgk1, NDRG2, and SCNN1A. Conclusions: Our data demonstrate that MR mutations differentially affect individual gene expression in a promoter-dependent manner. Investigation of differential gene expression profiles in PHA1 may allow a better understanding of the molecular substrate of phenotypic variability and to elucidate pathogenic mechanisms underlying the disease. (J Clin Endocrinol Metab 96: E519-E527, 2011)
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Context: Melanocortin receptor 4 (MC4R) deficiency is characterized by increased linear growth greater than expected for the degree of obesity. Objective: The objective of the investigation was to study the somatotroph axis in obese MC4R-deficient patients and equally obese controls. Patients and Methods: We obtained anthropometric measurements and insulin concentrations in 153 MC4R-deficient subjects and 1392 controls matched for age and severity of obesity. We measured fasting IGF-I, IGF-II, IGF binding protein (IGFBP)-1, IGFBP-3, and acid-labile subunit levels in a subset of 33 MC4R-deficient patients and 36 control subjects. We examined pulsatile GH secretion in six adult MC4R-deficient subjects and six obese controls. Results: Height so score was significantly greater in MC4R-deficient children under 5 yr of age compared with controls (mean +/- SEM: 2.3 +/- 0.06 vs. 1.8 +/- 0.04, P < 0.001), an effect that persisted throughout childhood. Final height (cm) was greater in MC4R-deficient men (mean +/- SEM 173 +/- 2.5 vs. 168 +/- 2.1, P < 0.001) and women (mean 165 +/- 2.1 vs. 158 +/- 1.9, P < 0.001). Fasting IGF-I, IGF-II, acid-labile subunit, and IGFBP-3 concentrations were similar in the two groups. GH levels were markedly suppressed in obese controls, but pulsatile GH secretion was retained in MC4R deficiency. The mean maximal GH secretion rate per burst (P < 0.05) and mass per burst (P < 0.05) were increased in MC4R deficiency, consistent with increased pulsatile and total GH secretion. Fasting insulin levels were markedly elevated in MC4R-deficient children. Conclusions: In MC4R deficiency, increased linear growth in childhood leads to increased adult final height, greater than predicted by obesity alone. GH pulsatility is maintained in MC4R deficiency, a finding consistent with animal studies, suggesting a role for MC4R in controlling hypothalamic somatostatinergic tone. Fasting insulin levels are significantly higher in children carrying MC4R mutations. Both of these factors may contribute to the accelerated growth phenotype characteristic of MC4R deficiency. (J Clin Endocrinol Metab 96: E181-E188, 2011)
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Context: Genetic factors that influence the response to recombinant human GH (rhGH) therapy remain mostly unknown. To date, only the GH receptor gene has been investigated. Objective: The aim of the study was to assess the influence of a polymorphism in the IGF-binding protein-3 (IGFBP-3) promoter region (-202 A/C) on circulating IGFBP-3 levels and growth response to rhGH therapy in children with GH deficiency (GHD). Design and Patients: -202 A/C IGFBP3 genotyping (rs2854744) was correlated with data of 71 children with severe GHD who remained prepubertal during the first year of rhGH treatment. Main Outcome Measures: We measured IGFBP-3 levels and first year growth velocity (GV) during rhGH treatment. Results: Clinical and laboratory data at the start of treatment were indistinguishable among patients with different -202 A/C IGFBP3 genotypes. Despite similar rhGH doses, patients homozygous for the A allele presented higher IGFBP-3 SD score levels and higher mean GV in the first year of rhGH treatment than patients with AC or CC genotypes (first year GV, AA = 13.0 +/- 2.1 cm/yr, AC = 11.4 +/- 2.5 cm/yr, and CC = 10.8 +/- 1.9 cm/yr; P = 0.016). Multiple linear regression analyses demonstrated that the influence of -202 A/C IGFBP3 genotype on IGFBP-3 levels and GV during the first year of rhGH treatment was independent of other variables. Conclusion: The -202 A allele of IGFBP3 promoter region is associated with increased IGFBP-3 levels and GV during rhGH treatment in prepubertal GHD children. (J Clin Endocrinol Metab 94: 588-595, 2009)
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The HLA-G gene is predominantly expressed at the maternal-fetal interface. It has been associated with maternal-fetal tolerance and in the inhibition of cytotoxic T lymphocyte and natural killer cytolytic functions. At least two variations in the 3` untranslated region (UTR) of HLA-G locus are associated with HLA-G expression levels, the 14-bp deletion/insertion polymorphism and the +3142 single-nucleotide polymorphism (SNP). However, this region has not been completely characterized yet. The variability of the 3`UTR of HLA-G gene and its haplotype structure were characterized in 155 individuals from Brazil, as well as HLA-G alleles associated with each of the 3`UTR haplotype. The following eight variation sites were detected: the 14-bp polymorphism and SNPs at the positions +3003T/C, +3010C/G, +3027A/C, +3035C/T, +3142G/C, +3187A/G and +3196C/G. Similarly, 11 different 3`UTR haplotypes were identified and several HLA-G alleles presented only one 3`UTR haplotype. In addition, a high linkage disequilibrium among the variation sites was detected, especially among the 14-bp insertion and the alleles +3142G and +3187A, all previously associated with low mRNA availability, demonstrating that their effects are not independent. The detailed analyses of 3`UTR of the HLA-G locus may shed some light into mechanisms underlying the regulation of HLA-G expression. Genes and Immunity (2010) 11, 134-141; doi: 10.1038/gene.2009.74; published online 1 October 2009