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Radiofrequency ablation (RFA) has widespread popularity due to its immune-modulation effects in many cancers. Optimal settings to apply RFA in pancreatic cancer, in which the advanced stage of the tumor at the diagnosis makes various therapeutic approaches fail, are still demanding. We report the case of a patient with unresectable pancreatic cancer in which 3 repetitive RFA has been applied over a period of 3 months. Results revealed an improvement in the patient's clinical condition associated with the reduced incidence of CD4+CD45RO+ T lymphocytes and declined TGF-ß level in serum. The good quality of life and disease-free survival were maintained for the next months. Booster application of RFA procedure might be a promising option to improve the quality of life in pancreatic cancer patients.
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Many patients with hepatocellular carcinoma cannot be treated surgically because of the advanced stage of the tumor and/or coexisting cirrhosis. Transcatheter arterial embolization (TAE) represents an alternative therapeutic approach for some of these patients. However, it is not a curative measure, and an additional therapy is required to eradicate the residual disease. In this communication, we report a case of 55-year-old man with giant hepatocellular carcinoma located in the right lobe of the liver that was successfully treated with TAE. TAE completely devascularized the tumor in one session. Despite of postembolization antibiotic therapy, complete tumor necrosis led to abscess formation. After 57 days of abscess drainage, necrotic tumor tissue was completely evacuated from the drained cavity; no viable tumor tissue was identified by computed tomography/magnetic resonance imaging scan on a 5 year follow-up. TAE procedure can be suggested as a modulator of antitumor immune response, by exposing tumor antigens after necrosis leading to inflammation. In addition to necrosis caused by TAE, an antimicrobial acute inflammatory reaction in the treated area led to the complete destruction of the giant tumor.
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Adipokines may link adipose tissue to the inflammatory, metabolic, and immune dysregulation. The variation of adipokine levels within individuals, intercorrelations, and relationships to well-established measures of adiposity are incompletely defined. The main goal of the present study was quantitative evaluation of the genetic interrelationships between obesity and adipokines in normal human population. The study sample comprised 272 families of various sizes, including 530 men and 531 women aged 18-80 years, randomly recruited in rural population living in Russia. Various fatness and fat distribution measures (OB), blood pressure (BP), and plasma levels of several adipokines (AC), such as adiponectin, leptin, resistin, and IGFBP-1, have been measured. The likelihood ratio tests clearly revealed that genetic effect for all studied phenotypes was highly significant (P < 0.001) and accounted for 45.9% +/- 8.1%, 33.7% +/- 7.9%, 35.7% +/- 9.8% of variation for AC, OB, and BP, respectively. The pairwise bivariate analyses showed that strong phenotypic correlation between the obesity (OB) and adipocytokines (AC) was caused by both common genetic and environmental factors (r(G) = 0.597 +/- 0.116, r(E) = 0.671 +/- 0.051). The phenotypic correlation between BP and OB is explained by shared genetic factors only (r(G) = 0.532 +/- 0.109), whereas the phenotypic correlation between BP and AC has only common environment basis (r(E) = -0.212 +/- 0.081) and was mostly due to the correlation observed in females. Our results suggest that genetic factors play a significant role in regulation of variation of the examined traits. The variation of OB traits is almost fully due to genes influencing variation of AC, whereas the correlation between BP and AC is only marginally significant and caused only by shared environment.
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Adipocinas/genética , Pressão Sanguínea/genética , Obesidade/genética , Adipocinas/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meio Ambiente , Feminino , Variação Genética , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Fenótipo , Análise de Regressão , Fatores de Risco , População Rural , Federação RussaRESUMO
Background: Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related deaths in developed countries. The liver is the most prevalent site of metastasis from CRC. Currently, the gold-standard treatment for colorectal liver metastases (CLMs) is surgical resection. However, depending on the pattern of the disease, a significant number of patients may require different approaches alone or in combination with surgery, including thermal ablation (radiofrequency (RFA) or microwave (MWA) ablation) or transarterial liver-directed therapies, although the latter is not yet part of the standard treatment for CRC liver metastases. Methods and Results: We present the case of a 63-yearold man with bilobar CLM who was treated with transarterial embolization (TAE) and RFA followed by chemotherapy. A post-RFA study of immune parameters revealed the downregulation of CD39 expression in the circulating CD4+ T cell population and a reduction of the serum levels of cytokines IL-10, TGF-ß, IFN-gamma and IL-17, which positively correlated with the diminished serum level of gamma-glutamyl transferase (GGT) and the subdued inflammatory markers: the neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR). Later, the patient underwent chemotherapy. Liver failure developed within two years and nine months following tumour ablation, leading to the death of the patient. Conclusions: However, the denial of adjuvant chemotherapy by the patient gave us the opportunity to assess the immunomodulatory changes following RFA in the absence of any other therapeutic modalities.
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Introduction: Hepatic cancer is a highly lethal tumour with increasing worldwide incidence. These tumours are characterized by the proliferation of malignant cells, generalised immunosuppression and chronic inflammation marked with an increase in inflammatory markers as a neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR) and overexpression of CD4+CD39+ on T lymphocytes. The studies have outlined immunomodulatory changes in liver cancer patients as the plausible explanation for the better survival. The aim of this pilot study was understand the possible immunomodulatory effect of radiofrequency (RF) energy and liver resection (non-radiofrequency based devices; non-RF device) in relation to NLR, PLR and expression of CD4+CD39+ T lymphocytes and compare the magnitude of these changes. Material and Methods: In the present study, 17 patients with hepatic cancer were prospectively divided into treatment groups radiofrequency ablation (RFA group) and Liver resection using non-RF devices (LR group). A blood sample was collected from each patient, one month before and after the procedure and compared with the blood samples of age-matched healthy volunteers for group wise comparison. The Mann-Whitney U test, Mc Nemar test and Wilcoxon rank test were used for statistical comparisons as appropriate. Results: A decrease in NLR was reported after RFA from 4.7±3.3 to 3.8±1.8 (P=0.283), in contrary to an increase from 3.5±2.8 to 4.5±3.2 (P=0.183) in LR group. Likewise, a decrease was discerned in PLR following RFA from 140.5±79.5 to 137±69.2 respectively (P=0.386) and increase in the LR group from 116±42.2 to 120.8±29 respectively (P=0.391). A significant decrease in CD4+CD39+ lymphocytes from 55.8±13.8 to 24.6±21.1 (P=0.03) was observed in RFA group whilst a significant increase was reported in LR group from 47.6±8.8 to 55.7±33.2 (P=0.38). Conclusion: Studies have shown that decrease in the NLR, PLR and expression of CD4+CD39+ on T lymphocytes as the marker of better survival in hepatic cancer patients and our findings have confirmed that these changes can be induced following application of RF energy. Moreover, this could be the explanation of better survival observed in different studies using RFA or other RF-based devices in comparison to non-RF based liver resection techniques. However, further larger studies are needed to confirm these findings.
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Case report presents the successful treatment of unresectable liver metastasis in a patient with colon cancer. A 44-year-old male underwent right hemicolectomy followed by capecitabine for a moderately differentiated adenocarcinoma of the colon. 2 years later, a liver metastatic lesion was detected and had increased in size despite chemotherapy with capecitabine plus oxaliplatin (XELOX). Curative liver resection was conducted after conversion of unresectable tumor to resectable by transarterial chemoembolization followed by chemotherapy - irinotecan with fluorouracil and folinic acid (FOLFIRI). No recurrence was observed during 22-month follow-up after hepatectomy.
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Adenocarcinoma/terapia , Camptotecina/análogos & derivados , Quimioembolização Terapêutica , Neoplasias do Colo/terapia , Fluoruracila/uso terapêutico , Leucovorina/uso terapêutico , Neoplasias Hepáticas/terapia , Adenocarcinoma/diagnóstico , Adenocarcinoma/secundário , Adulto , Biomarcadores/metabolismo , Camptotecina/uso terapêutico , Capecitabina/uso terapêutico , Colectomia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Hepatectomia , Humanos , Mediadores da Inflamação/metabolismo , Irinotecano , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Masculino , Microesferas , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Indução de RemissãoRESUMO
Recent studies have demonstrated that the accumulation of senescent endothelial cells may be the primary cause of cardiovascular diseases. Because of their multifunctional properties, endothelial cells actively take part in stimulating the immune system and inflammation. In addition, ageing is characterized by the progressive deterioration of immune cells and a decline in the activation of the immune response. This results in a loss of the primary function of the immune system, which is eliminating damaged/senescent cells and neutralizing potential sources of harmful inflammatory reactions. In this review, we discuss cellular senescence and the senescence-associated secretory phenotype (SASP) of endothelial cells and summarize the link between endothelial cells and immunosenescence. We describe the possibility that age-related changes in Toll-like receptors (TLRs) and microRNAs can affect the phenotypes of senescent endothelial cells and immune cells via a negative feedback loop aimed at restraining the excessive pro-inflammatory response. This review also addresses the following questions: how do senescent endothelial cells influence ageing or age-related changes in the inflammatory burden; what is the connection between ECs and immunosenescence, and what are the crucial hypothetical pathways linking endothelial cells and the immune system during ageing.
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Envelhecimento/fisiologia , Senescência Celular/fisiologia , Células Endoteliais/fisiologia , Imunossenescência/fisiologia , Animais , Humanos , Inflamação/genética , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , FenótipoRESUMO
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Portal vein tumor thrombosis (PVTT) is a frequent entity in HCC, which strictly limits the gold standard treatment options such as surgical resection and transarterial chemoembolization. Therefore, the prognosis of patients with PVTT is extremely poor and an emergence of seeking an alternative option for intervention is inevitable. We present a case of a 60-year-old male patient with HCC induced PVTT who was subjected to the intraportal RFA and stenting-VesOpen procedure. No additional medical intervention was performed. The repeated CT performed 5 months after the VesOpen procedure revealed significant decrease of the tumor size, patent right, and main portal vein and a recanalization of the left portal vein, which was not processed. At this time point, liver functional tests, appetite, and general condition of the patient were improved evidently. This report designates the RFA as an instrumental option of therapeutic intervention for HCC patients with PVTT.
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Recent literature has shown that circulating levels of insulin-like growth factor I (IGF-I) and/or IGF binding proteins (IGF-BPs) may be of importance in the risk assessment of several chronic diseases including cancer, cardiovascular disease, diabetes mellitus and so on. The present study examined the extent of genetic and environmental influences on the populational variation of circulating IGF-I and IGF-BP-1 in apparently healthy and ethnically homogeneous white families. The plasma levels of each of the studied biochemical indices were determined by enzyme-linked immunoassay in 563 individuals aged 18 to 80 years. Quantitative genetic analysis showed that the IGF-I variation was appreciably attributable to genetic effects (47.1% +/- 9.0%), whereas for IGF-BP-1, only 23.3% +/- 7.8% of the interindividual variation was explained by genetic determinants. Common familial environment factors contributed significantly only to IGF-BP-1 variation (23.3% +/- 7.8%). In addition, we examined the covariations between these molecules and between them and IGF-BP-3 and leptin that were previously studied in the same sample. The analysis revealed that the pleiotropic genetic effects were significant for 2 pairs of traits, namely for IGF-I and IGF-BP-3, and for IGF-BP-1 and leptin. The bivariate heritability estimates were 0.21 +/- 0.04 and 0.15 +/- 0.05. The common environmental factors were consistently a significant source of correlation between all pairs (barring IGF-I and leptin) of the studied molecules; they were the sole predictors of correlation between IGF-I and IGF-BP-1, and between IGF-BP-1 and IGF-BP-3. Our results affirm the existence of specific and common genetic pathways that in combination determine a substantial proportion of the circulating variation of these molecules.
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Predisposição Genética para Doença , Leptina/sangue , Somatomedinas/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: To determine the ranges of variation of circulating receptor activator of nuclear factor-kappaB ligand (RANKL)/osteoprotegerin (OPG)/macrophage-colony stimulating factor(M-CSF) and to ascertain their potential relationships with age, sex and menopausal status in women, and with sex hormones in a population-based healthy cohort. SUBJECTS AND METHODS: Blood samples were collected with EDTA after an overnight fast. The plasma levels of each of the above biochemical indices were measured by ELISA in a total of 566 apparently healthy individuals aged 18-75 years. RESULTS: The plasma concentrations of cytokine molecules in the entire sample ranged from 674 to 4929 pg/ml for OPG, from 105 to 4468 pg/ml for soluble RANKL (sRANKL), and from 187 to 7604 pg/ml for M-CSF. The OPG levels demonstrated a clear positive correlation with age in both sexes (r=0.42 and 0.43, P<0.001, for men and women respectively). Application of the two-interval mathematical model revealed that in females OPG levels were age-independent until age 42, but then showed clear and significant correlation with age (r=0.48, P<0.001). As a result, young females (before 42 years) had a substantially lower average OPG level, 1377.8+/-327.68 pg/ml, in comparison with older women, 1666.02+/-397.14 pg/ml. The M-CSF correlation with age was significantly greater in women (r=0.29, P<0.001) compared with men (r=0.17, P<0.01). Significant negative correlations between plasma levels of both OPG and M-CSF with estradiol concentrations were observed in women (r=-0.39, P<0.01; r=-0.25, P<0.001 respectively). sRANKL did not correlate with either age or sex hormones in either women or men. CONCLUSION: Age and sex affect differently the interindividual variation of OPG, RANKL and M-CSF. Our observations could form the basis for further research to establish provisional reference limits for OPG and RANKL, which are potential markers for benign and malignant processes in bone.
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Proteínas de Transporte/sangue , Fator Estimulador de Colônias de Macrófagos/sangue , Glicoproteínas de Membrana/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Densidade Óssea/fisiologia , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Estradiol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligante RANK , Radioimunoensaio , Receptor Ativador de Fator Nuclear kappa-B , Fatores Sexuais , Estatísticas não Paramétricas , Testosterona/sangueRESUMO
BACKGROUND: T cell-mediated immune responses contribute to the hepatocellular injury during autoimmune hepatitis, viral infection, and hepatotoxins. Pharmacological compounds regulating immune responses are suitable candidates for prevention/treatment of this pathology. Therefore, the main aim of this study was to define the effects of antioxidant, anti-inflammatory mixture of citrus peel extract (CPE) on the immune-mediated liver injury. METHODS: The influence of CPE on liver injury was determined by the activity of transaminases in plasma and the histological changes. Anti-inflammatory and antioxidant effects were studied by measuring frequency of T regulatory cells (Tregs), cytokines (TNF-α, IL-10, and IFN-γ), and nitric oxide levels. RESULTS: The CPE application notably prevents development of liver injury through decreasing levels of both cytokines (TNF-alpha, INF) and regulatory T cells and increasing levels of IL-10. CPE injection also diminished the serum NO, which in turn resulted in evident reduction of the liver damage. CONCLUSION: Our findings represent the primary preclinical data indicating that the CPE in vivo could ameliorate Con A induced hepatitis. The low dose of CPE most likely can be used for the treatment of the T cell-mediated liver injury as in autoimmune hepatitis, alcoholic hepatitis, and chronic viral hepatitis.
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Antioxidantes/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Hepatite/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citrus/química , Concanavalina A/toxicidade , Hepatite/imunologia , Hepatite/patologia , Interferon gama/sangue , Interleucina-10/sangue , Camundongos , Óxido Nítrico/sangue , Extratos Vegetais/química , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T Reguladores/imunologia , Transaminases/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
BACKGROUND: Measurement of angiogenin in plasma provides important prognostic and diagnostic information in variety of malignancies and may even correlate with cancer's progression. Nevertheless, nowadays, specific physiological mechanisms of this protein action as well as major factors regulating its circulating levels normally and in pathology are still poorly understood. The main objectives of this study were to examine the contribution of a number of endogenous factors, such as sex, age, body size and genetic effects on the production of angiogenin in apparently healthy individuals, and to assess the correlations in circulating levels between angiogenin and other molecules involved in angiogenesis. METHODS: The plasma levels of angiogenin and each of the additional cytokines [interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), macrophage-colony stimulating factor (M-CSF), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), soluble intercellular adhesion molecule-1 (sICAM)] were determined by enzyme-linked immunoassay in a large family based sample. RESULTS: Angiogenin levels were significantly higher in man than in women (360.64 +/- 104.04 ng/ml vs. 322.15 +/- 100.34 ng/ml, P < 0.01) and significantly correlated with age (P < 0.01) in both sexes. Genetic analysis showed that adjusted for potential covariates, 37.4 +/- 7.1% of angiogenin variation was attributable to putative genetic factors. The results of our study revealed that angiogenin concentrations were positively and significantly (P < 0.05) associated with sICAM, IL-6, TNF-alpha and M-CSF levels in the female cohort. CONCLUSIONS: Our data provide reliable evidence for the substantial role of genetic factors in the determination of the phenotypic variability of angiogenin plasma levels. These findings of our study, including circulating angiogenin reference limits in healthy population and its correlation with angiogenic cytokines, may be of importance in determination of early stages of pathological angiogenesis.
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Citocinas/sangue , Ribonuclease Pancreático/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Tamanho Corporal , Meio Ambiente , Saúde da Família , Feminino , Variação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Fenótipo , Ribonuclease Pancreático/genética , Fatores SexuaisRESUMO
In our research we examined the contribution of putative genetic sources on interindividual variation and cross-sectional correlations of several adhesion molecules, including intracellular (ICAM-1) and vascular cell adhesion molecules (VCAM-1) and E-selectin, in a population-based sample of ethnically homogeneous families of European origin. The plasma levels of these molecules were measured in 947 apparently healthy individuals from 217 nuclear families. Quantitative statistical-genetic analysis implementing the model fitting technique revealed significant parent/offspring and sibling correlations (p < 0.01) for all three molecules. The putative genetic effects explained 55.2 +/- 7.2% (VCAM-1), 63.3 +/- 7.5% (ICAM) and 63.8 +/- 8.1% (E-selectin) of the variation. Common family environmental factors also significantly influenced the variation of E-selectin (13%) and VCAM-1 (28.6%). The main results of our bivariate analysis showed that the observed phenotypic correlations between ICAM-1 and VCAM-1, and between ICAM-1 and E-selectin, were mostly attributable to shared environmental factors (r(E)= 0.896 and 0.737, respectively; p < 0.01). However, the correlation between VCAM-1 and E-selectin was likely caused by common genetic effects (r(G)= 0.334, p < 0.05). Our results show that familial clustering of adhesion molecules is likely due to strong genetic effects, supplemented with shared environmental factors.
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Selectina E/sangue , Meio Ambiente , Variação Genética , Molécula 1 de Adesão Intercelular/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Adolescente , Adulto , Idoso , Estudos Transversais , Família , Feminino , Ligação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , População Branca/etnologia , População Branca/genéticaRESUMO
Dysregulation of cytokines synthesis is thought to play a role in the development of a number of age-related conditions, such as rheumatoid arthritis, osteoporosis, atherosclerosis, and others, but observational studies have led to contradictory results. We investigated potential familial influences on the plasma levels of IL-6 and TNF-alpha in 91 nuclear and more complex pedigrees of Caucasian ethnic origin (N=401 individuals). The maximum likelihood based variance decomposition analysis showed significant positive correlation between circulating IL-6 and age in both genders. The magnitude of these correlations in our sample ranged from 0.22 in females to 0.28 in males (P<0.001). Significant association between TNF-alpha and IL-6 (r=0.28, r=0.43; P<0.001; respectively for men and women) was also observed. Likelihood ratio test clearly revealed that additive genetic effect for TNF-alpha was highly significant (P<0.001), and accounted over 80% of its variation, adjusted for IL-6 levels and age. In contrast, heritability estimate for IL-6 adjusted for age and TNF-alpha, revealed small contribution of genetic factors (24.1 +/- 10.2%). The bivariate variance component analysis demonstrated that significant relationship between IL-6 and TNF-alpha was due to shared environment only (r(E)=0.760 +/- 0.140). As evinced from our complex segregation analysis the nature of the genetic determinant of each of these two cytokines is quite complex and it is probably oligogenic.
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Interleucina-6/sangue , Interleucina-6/genética , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Adulto , Fatores Etários , Idoso , Peso Corporal , Núcleo Celular/metabolismo , Feminino , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Valores de Referência , Análise de RegressãoRESUMO
Circulating levels of insulin-like growth factor binding protein-3 (IGFBP-3) vary greatly between normal individuals, but until now little attention has been given to the study of the genetic factors involved in IGFBP-3 variability in healthy populations. The present study investigated the extent and pattern of the possible genetic influences on plasma levels of IGFBP-3 in 91 nuclear and more complex families, totaling 396 individuals (201 males and 195 females) of Caucasian ethnic origin. The variance decomposition analysis, was performed using the FISHER statistical package. In the second stage of the analysis, we used complex segregation analysis as implemented in the statistical package MAN. Significant negative correlation was revealed between age and plasma levels of IGFBP-3 in both sexes ( r=-0.49; r=-0.23; P<0.001). Multivariate analysis identified age, body weight, and height as significant covariates in men, but for women only age had a considerable effect. It has been demonstrated that about 57.7% of IGBP-3 variation adjusted for significant confounding factors was attributable to genetic factors. The results of bivariate variance decomposition analysis showed no significant genetic and phenotypic correlation between the mineral density of hand bones and IGFBP-3. Segregation analysis revealed the existence of a potential major gene effect that was able to explain some 27.5% of IGFBP-3 variation. Multifactorial effects, likely, unknown minor genes, contributed an additional 30% to IGFBP-3 variation. The segregation analysis also provided evidence of significant genotype X sex interaction in the determination of plasma levels of IGFBP-3.
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Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Adolescente , Adulto , Fatores Etários , Idoso , Estatura , Peso Corporal , Densidade Óssea , Estradiol/sangue , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Análise Multivariada , Linhagem , Fenótipo , Pós-Menopausa , Pré-Menopausa , Testosterona/sangueRESUMO
Leptin is secreted primarily by the adipocytes and plays an important role in the regulation of food intake and energy expenditure. In addition to its adipostatic function, it has been demonstrated that leptin directly enhances stromal cell differentiation to osteoblasts, and since such precursor cells are potential targets for leptin, the latter could possibly mediate the relationship between obesity and bone mass and size. To address this question, we studied phenotypic and genetic correlations between the circulating levels of leptin and hand bone size (BS) and geometry (BG) of the radiographic hand in a healthy and ethnically homogeneous sample of pedigrees. We also attempted to evaluate to what extent potential leptin/BS/BG correlations are modified by an individual's obesity traits, specifically his/her BMI. Our research has shown that leptin, BMI and the corresponding bone measures are clearly inherited traits (0.46+/-0.11, 0.35+/-0.16, 0.62+/-0.12 and 0.51+/-0.09, respectively). The bivariate variance component analysis revealed very strong and significant genetic and environmental correlations between circulating leptin and BMI ( r(G)=0.86+/-0.09, r(E)=0.75+/-0.05, P<0.001). Furthermore, genetic correlations between leptin and hand bone characteristics proved inverse and statistically significant ( r(G)=-0.35+/-0.01 and -0.45+/-0.10 for BS and BG, respectively), while corresponding environmental correlations were low ( r(E)=-0.14+/-0.15 and -0.07+/-0.14) and they could be constrained to zero without significant deterioration of the model fit to the data ( P>0.10). However, despite the extremely strong relationship between leptin and BMI, we failed to detect phenotypic or genetic correlations between BMI and our two hand bone measures. Thus our study provided evidence that plasma leptin levels may be statistically significant predictor of hand bone size and geometry, and may play a physiological role in maintaining bone mass as well as in regulation of hand bone proportions.