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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Expressão da leptina e seu receptor no câncer de próstata / Leptin and leptin receptor expression in prostate cancer

Clarice Fraga Esteves Maciel Osorio 12 March 2014 (has links)
O câncer de próstata é o tumor não cutâneo mais comum entre homens e responsável pela segunda maior mortalidade entre os tumores neste sexo. Diferentes métodos são utilizados com o objetivo de determinar o prognóstico do paciente portador de câncer de próstata, contudo existe grande heterogeneidade quando estes são usados individualmente. A leptina é um hormônio peptídico envolvido na regulação da ingestão alimentar, do metabolismo, do gasto energético, além de função neuroendócrina. Este hormônio parece estar envolvido na patogênese de alguns tipos de tumores, inclusive os adenocarcinomas de próstata. Até o presente não se tem certeza se a leptina e seu receptor possam ser utilizados como fatores prognósticos no cancer de próstata. O objetivo do trabalho foi correlacionar os perfis de imunomarcação da leptina e seu receptor em adenocarcinomas de próstata com diferentes fatores prognósticos e comparar as análises de imunomarcação da leptina e seu receptor em adenocarcinomas de próstata por métodos semiquantitativos e quantitativos (morfometria). Foram analisadas 532 peças cirúrgicas de prostatectomias radicais por câncer prostático. A partir destas amostras, após estudo histopatológico, foi montado um arranjo de matriz tecidual, contendo fragmentos de áreas tumorais e não tumorais (peritumorais) destas amostras. Estas foram imunomarcadas com anticorpos antileptina e antirreceptor de leptina. Análises subjetivas (feitas por dois observadores) e objetivas (através da contagem de pontos) foram realizadas em cada uma das imunomarcações. Estes resultados foram comparados e correlacionados com os seguintes fatores prognósticos: invasão perineural, embolização neoplásica vascular, comprometimento bilateral da próstata, invasão das vesículas seminais, comprometimento de margem vesical, de margem uretral e de margem cirúrgica de ressecção. Houve diferença significativa entre as análises subjetivas dos dois observadores e, portanto, estas não foram utilizadas para as demais comparações. Em relação às análises objetivas, foi verificado que a expressão do receptor de leptina estava diminuída nos tumores com comprometimento de margem cirúrgica, de margem uretral e de vesículas seminais. Ainda foi observado correlação entre a expressão desse receptor e o somátório dos fatores prognósticos analisados. Para as demais análises não foi verificada diferença significativa. Métodos semiquantitativos podem ter grande variação e devem ser preteridos em relação a métodos quantitativos para as análises realizadas neste estudo. Nem a leptina nem o seu receptor apresentaram alterações de sua expressão em amostras neoplásicas de próstata quando comparado àquelas não neoplásicas. O receptor de leptina apresentou uma diminuição da sua expressão em tumores com margem cirúrgica comprometida, margem uretral comprometida e com vesículas seminais comprometidas. Houve correlação negativa entre o percentual de área imunomarcada com o anticorpo antirreceptor de leptina e o somatório dos fatores prognósticos analisados. / Prostate cancer is the most common non-cutaneous tumor among men and accounted for the second highest mortality rate among tumors in this sex. Different methods are used to determine the prognosis of patients with prostate cancer, yet there is great heterogeneity when they are used individually. Leptin is a peptide hormone, involved in the regulation of food intake, metabolism, energy expenditure, and neuroendocrine function. This hormone appears to be involved in the pathogenesis of some types of tumors, including prostate adenocarcinomas. Up to the present, it is uncertain if leptin and its receptor may be used as prognostic factors in prostate cancer. The objective of this study was correlate the profiles of immunostaining of leptin and its receptor in prostate adenocarcinomas with different prognostic factors and compare the analysis of immunostaining of leptin and its receptor in prostate adenocarcinomas by semi quantitative and quantitative methods (morphometry). A total of 532 surgical specimens from radical prostatectomies from prostate cancer had been studied. After pathological examination, these samples were included in a tissue microarray containing fragments of tumoral and non-tumoral areas (peritumoral areas). These were immunostained with antibodies antileptin and antileptin receptor. Subjective analysis (made by two observers) and objective (by counting points) were performed on each sample. These results were compared and correlated with the following prognostic factors: perineural invasion, neoplasic vascular embolization, bilateral involvement of the prostate, seminal vesicle invasion, involvement of vesical margin, involvement of urethral margin and involvement of resection surgical margin. There were significant differences between subjective analyses of the two observers, and, therefore, they were not used for other comparisons. Regarding the objective analysis, it was found that leptin receptor expression was reduced in tumors with involvement of the surgical margin, urethral margin and seminal vesicles invasion. Further, there were correlation between the expression of this receptor and the sum of prognostic factors. For the other analyses, it was not observed any significant difference. Semi quantitative methods can have great variation and should be passed over in relation to quantitative methods for the analysis performed in this study. Neither leptin nor its receptor exhibited changes in their expression in neoplastic prostatic samples compared to those that are not neoplastic. The leptin receptor showed a decreased expression in tumors with positive surgical margin, positive urethral margin and involvement of seminal vesicles. There were a negative correlation between the percentage of immunostaining area with antibody antileptin receptor and the sum of prognostic factors.
12

Expressão da leptina e seu receptor no câncer de próstata / Leptin and leptin receptor expression in prostate cancer

Clarice Fraga Esteves Maciel Osorio 12 March 2014 (has links)
O câncer de próstata é o tumor não cutâneo mais comum entre homens e responsável pela segunda maior mortalidade entre os tumores neste sexo. Diferentes métodos são utilizados com o objetivo de determinar o prognóstico do paciente portador de câncer de próstata, contudo existe grande heterogeneidade quando estes são usados individualmente. A leptina é um hormônio peptídico envolvido na regulação da ingestão alimentar, do metabolismo, do gasto energético, além de função neuroendócrina. Este hormônio parece estar envolvido na patogênese de alguns tipos de tumores, inclusive os adenocarcinomas de próstata. Até o presente não se tem certeza se a leptina e seu receptor possam ser utilizados como fatores prognósticos no cancer de próstata. O objetivo do trabalho foi correlacionar os perfis de imunomarcação da leptina e seu receptor em adenocarcinomas de próstata com diferentes fatores prognósticos e comparar as análises de imunomarcação da leptina e seu receptor em adenocarcinomas de próstata por métodos semiquantitativos e quantitativos (morfometria). Foram analisadas 532 peças cirúrgicas de prostatectomias radicais por câncer prostático. A partir destas amostras, após estudo histopatológico, foi montado um arranjo de matriz tecidual, contendo fragmentos de áreas tumorais e não tumorais (peritumorais) destas amostras. Estas foram imunomarcadas com anticorpos antileptina e antirreceptor de leptina. Análises subjetivas (feitas por dois observadores) e objetivas (através da contagem de pontos) foram realizadas em cada uma das imunomarcações. Estes resultados foram comparados e correlacionados com os seguintes fatores prognósticos: invasão perineural, embolização neoplásica vascular, comprometimento bilateral da próstata, invasão das vesículas seminais, comprometimento de margem vesical, de margem uretral e de margem cirúrgica de ressecção. Houve diferença significativa entre as análises subjetivas dos dois observadores e, portanto, estas não foram utilizadas para as demais comparações. Em relação às análises objetivas, foi verificado que a expressão do receptor de leptina estava diminuída nos tumores com comprometimento de margem cirúrgica, de margem uretral e de vesículas seminais. Ainda foi observado correlação entre a expressão desse receptor e o somátório dos fatores prognósticos analisados. Para as demais análises não foi verificada diferença significativa. Métodos semiquantitativos podem ter grande variação e devem ser preteridos em relação a métodos quantitativos para as análises realizadas neste estudo. Nem a leptina nem o seu receptor apresentaram alterações de sua expressão em amostras neoplásicas de próstata quando comparado àquelas não neoplásicas. O receptor de leptina apresentou uma diminuição da sua expressão em tumores com margem cirúrgica comprometida, margem uretral comprometida e com vesículas seminais comprometidas. Houve correlação negativa entre o percentual de área imunomarcada com o anticorpo antirreceptor de leptina e o somatório dos fatores prognósticos analisados. / Prostate cancer is the most common non-cutaneous tumor among men and accounted for the second highest mortality rate among tumors in this sex. Different methods are used to determine the prognosis of patients with prostate cancer, yet there is great heterogeneity when they are used individually. Leptin is a peptide hormone, involved in the regulation of food intake, metabolism, energy expenditure, and neuroendocrine function. This hormone appears to be involved in the pathogenesis of some types of tumors, including prostate adenocarcinomas. Up to the present, it is uncertain if leptin and its receptor may be used as prognostic factors in prostate cancer. The objective of this study was correlate the profiles of immunostaining of leptin and its receptor in prostate adenocarcinomas with different prognostic factors and compare the analysis of immunostaining of leptin and its receptor in prostate adenocarcinomas by semi quantitative and quantitative methods (morphometry). A total of 532 surgical specimens from radical prostatectomies from prostate cancer had been studied. After pathological examination, these samples were included in a tissue microarray containing fragments of tumoral and non-tumoral areas (peritumoral areas). These were immunostained with antibodies antileptin and antileptin receptor. Subjective analysis (made by two observers) and objective (by counting points) were performed on each sample. These results were compared and correlated with the following prognostic factors: perineural invasion, neoplasic vascular embolization, bilateral involvement of the prostate, seminal vesicle invasion, involvement of vesical margin, involvement of urethral margin and involvement of resection surgical margin. There were significant differences between subjective analyses of the two observers, and, therefore, they were not used for other comparisons. Regarding the objective analysis, it was found that leptin receptor expression was reduced in tumors with involvement of the surgical margin, urethral margin and seminal vesicles invasion. Further, there were correlation between the expression of this receptor and the sum of prognostic factors. For the other analyses, it was not observed any significant difference. Semi quantitative methods can have great variation and should be passed over in relation to quantitative methods for the analysis performed in this study. Neither leptin nor its receptor exhibited changes in their expression in neoplastic prostatic samples compared to those that are not neoplastic. The leptin receptor showed a decreased expression in tumors with positive surgical margin, positive urethral margin and involvement of seminal vesicles. There were a negative correlation between the percentage of immunostaining area with antibody antileptin receptor and the sum of prognostic factors.
13

Leptin Receptor Compound Heterozygosity in Humans and Animal Models

Berger, Claudia, Klöting, Nora 15 February 2024 (has links)
Leptin and its receptor are essential for regulating food intake, energy expenditure, glucose homeostasis and fertility. Mutations within leptin or the leptin receptor cause early-onset obesity and hyperphagia, as described in human and animal models. The effect of both heterozygous and homozygous variants is much more investigated than compound heterozygous ones. Recently, we discovered a spontaneous compound heterozygous mutation within the leptin receptor, resulting in a considerably more obese phenotype than described for the homozygous leptin receptor deficient mice. Accordingly, we focus on compound heterozygous mutations of the leptin receptor and their effects on health, as well as possible therapy options in human and animal models in this review.
14

The Role of the Leptin Receptor on T Cells in Helicobacter Pylori Infection and Clearance in Mice

Emancipator, Douglas Steven 22 July 2008 (has links)
No description available.
15

Genomic and Physiological Differences for Ghrelin and Leptin Receptor in Lines of Chickens Selected for High and Low Body Weight

Kuo, Alice Yi-Wen 12 December 2003 (has links)
Autonomic nervous system (ANS) activity is related to body weight regulation. Based on the hypothesis that Most Obesities kNown Are Low In Sympathetic Activity (MONA LISA), it has been suggested that most obese subjects and animals have low sympathetic nervous system activity. Leptin, leptin receptor, and ghrelin genes influence the ANS regulation of body weight and food intake. The aim of this study was to investigate whether there are differences in leptin, the leptin receptor, or ghrelin regulation between lines of chickens selected for high (HWS) or low body weight (LWS). Intraperitoneal injections of reserpine were administrated to chickens from the HWS and LWS lines. Body weight and food intake were then compared to evaluate ANS regulation. While reserpine caused a transitory decrease in food intake and body weight in both lines, the magnitude of the change was greater in the HWS than in the LWS chickens. However, chickens from the LWS line exhibited greater catecholamine and indoleamine level changes in response to reserpine than those from the HWS line. Therefore, HWS chickens were more sensitive to the body weight-reducing effects of reserpine than LWS lines, while LWS chickens appeared to have greater sympathetic nervous system activity. Food and water intakes were differentially affected in HWS and LWS chickens in response to intracerebroventricular administration of human recombinant leptin. Leptin caused a linear decrease in food intake in the LWS line, but no effect on food intake in the HWS lines. The HWS chickens tended to have reduced water intake following leptin administration. These results suggest that the leptin receptor, or the down-stream neuropeptide regulation pathway mediating the effect of leptin; may be different between chickens from the HWS and LWS lines. Leptin, insulin like growth factor (IGF)-1, and IGF-2 concentrations in the plasma of HWS and LWS lines of chickens were evaluated. Leptin, IGF-1 and IGF-2 levels were significantly higher in the LWS than HWS chickens. The HWS female leptin concentrations were significantly lower than in HWS males or LWS females. Male chickens had greater IGF-1 concentrations in the plasma than female chickens. However, the concentration of IGF-2 did not differ between sexes. The difference in leptin concentrations in these lines and sexes may explain the differences in age of sexual maturity. Different IGF-1 and IGF-2 concentrations may be involved in the obese and anorexic conditions, fast and slow growth, and high and low food consumption found in these two lines of chickens. Differences in the gene sequence of the leptin receptor were observed in HWS and LWS lines of chickens. A single nucleotide polymorphism (SNP) in the intron between exon 8 and 9 introduced a restriction site for the enzyme Sel I in the HWS, but not the LWS line. Two SNP were detected in the leptin receptor cDNA region at nucleotides 189 and 234. At nucleotide 189, the LWS line has both a homozygous (T-T) and heterozygous (C-T), whereas the HWS line has only homozygous (T-T) form. The SNP found in nucleotide 234 introduces a restriction site Mse I in the HWS, but not the LWS line. These specific changes may be directly involved or closely linked to differences between the two lines in either the coding or regulatory domains of the leptin receptor. Differences in the leptin receptor gene expression between HWS and LWS lines of chickens in various organs and ages were observed. Leptin receptor expression in the whole brain was significantly different between sexes at 28 days-of-age in the HWS and LWS lines. The LWS line had higher leptin receptor gene expression in the liver at 2 days-of-age than at 56 and 363 days-of-age, but no differences were observed in the HWS line. In addition, at 2 days-of age, liver leptin receptor gene expression was higher in LWS than HWS chickens, but the reverse was observed at 363 days-of age. In adipose tissue, leptin receptor expression was higher in the LWS than HWS line. Leptin receptor expression in adipose tissue was greater at 363, than 28 and 56 days-of-ages. Our results showed that changes in the regulation of leptin and the leptin receptor were associated with sex, age, and growth. Differences in the ghrelin gene in the HWS and LWS lines under different feeding conditions were investigated. Both HWS and LWS chickens have six extra base pairs in the 5'-untranslated region. The LWS male ghrelin gene expression was significantly lower than in the LWS female and HWS male. The 84 day-old males had lower gene expression than 84 day-old females and 363 day-old males. When comparing different feeding methods, females allowed ad libitum feed consumption had a lower cycle threshold cycle number (CT) ratio than males allowed ad libitum feeding or fasted females. However, the inflection point cycle number of ad libitum fed females was lower than that of the ad libitum fed males, but greater than the fasted females. Ghrelin gene expression was different between the two lines of chickens, and the expression of ghrelin in chickens was influenced by body weight selection, sex, age, and feeding condition. / Ph. D.
16

A novel compound heterozygous leptin receptor mutation causes more severe obesity than in Leprdb/db mice

Berger, Claudia, Heyne, Henrike O., Heiland, Tina, Dommel, Sebastian, Höfling, Corinna, Guiu-Jurado, Esther, Lorenz, Jana, Roßner, Steffen, Dannemann, Michael, Kelso, Janet, Kovacs, Peter, Blüher, Matthias, Klöting, Nora 11 September 2024 (has links)
The leptin receptor (Lepr) pathway is important for food intake regulation, energy expenditure, and body weight. Mutations in leptin and the Lepr have been shown to cause early-onset severe obesity in mice and humans. In studies with C57BL/6NCrl mice, we found a mouse with extreme obesity. To identify a putative spontaneous new form of monogenic obesity, we performed backcross studies with this mouse followed by a quantitative trait locus (QTL) analysis and sequencing of the selected chromosomal QTL region. We thereby identified a novel Lepr mutation (C57BL/6N-LeprL536Hfs*6-1NKB), which is located at chromosome 4, exon 11 within the CRH2-leptin-binding site. Compared with C57BL/6N mice, LeprL536Hfs*6 develop early onset obesity and their body weight exceeds that of Leprdb/db mice at an age of 30 weeks. Similar to Leprdb/db mice, the LeprL536Hfs*6 model is characterized by hyperphagia, obesity, lower energy expenditure and activity, hyperglycemia, and hyperinsulinemia compared with C57BL/6N mice. Crossing Leprdb/wt with LeprL536Hfs*6/wt mice results in compound heterozygous LeprL536Hfs*6/db mice, which develop even higher body weight and fat mass than both homozygous Leprdb/db and LeprL536Hfs*6 mice. Compound heterozygous Lepr deficiency affecting functionally different regions of the Lepr causes more severe obesity than the parental homozygous mutations.
17

The Combined Effects of Leptin and Coenzyme Q10 in Ameliorating Obesity- Induced Infertility in Female Rats

Adedeji, Adekunle 01 August 2016 (has links)
Infertility is one of the major problems of obesity. Studies have shown that administration of leptin reversed obesity-induced infertility in rats and mice. Coenzyme Q10 (CoQ10) is an antioxidant and also supplies the energy needed for ovulation and embryo development. We hypothesized that leptin when combined with CoQ10 could greatly improve obesity-induced infertility. The results showed a significant decrease in food intake, body weight, and the regular estrous cycle was restored after treatment with leptin+CoQ10. There was a significant increase (p10 significantly (p10 can improve fertility in obese infertile female rats. This study could provide a novel therapeutic strategy for the treatment of infertility and formulation of new drugs for the treatment of obesity-induced infertility in females.
18

Análise molecular e morfométrica da próstata ventral de ratos injetados com leptina / Molecular and morphometric analysis of rat ventral prostate injhecteo with leptins

Jorge Luiz Alves Pereira 07 March 2012 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O objetivo deste estudo foi avaliar o efeito da administração de leptina no lobo ventral da próstata de ratos adultos. Vinte ratos Wistar machos e adultos foram divididos em 2 grupos: L - animais foram injetados com 50 μL diária de leptina (8 μg / 100 g PC, subcutânea) durante quatro dias e C - animais receberam o mesmo volume de solução salina. Perfil lipídico e níveis séricos de testosterona foram avaliados. O lobo ventral da próstata foi processado para análise histomorfométrica. Expressão dos genes da aromatase, receptor de andrógeno, receptores de estrógeno (α e β) e as isoformas dos receptores de leptina longa (Ob-Rb) e curta (Ob-Ra) foram avaliados por PCR em tempo real. Proliferação celular foi avaliada por imuno-histoquímica com PCNA. Os dados foram expressos como média  erro padrão e analisados pelo teste t de Student. Níveis séricos de colesterol aumentaram (C = 39,7 4,2; L = 55,2 4,2, mg / dL, P ≤ 0,02) e de testosterona (C = 1,6 0,43; L = 0,6 0,15, ng / dL, P ≤ 0,03) diminuíram no grupo L. A análise histomorfométrica mostrou uma redução na densidade de células (C = 8868 242; L = 8.211 210, mm2; P ≤ 0,04), na área total (C = 0,24 0,026; L = 0,10 0,009, mm2; P ≤ 0,001) e na área interna dos ácinos (C = 0,16 0,009; L = 0,08 0,006, mm2; P ≤ 0,0002). Por outro lado, houve um aumento na altura do epitélio (C = 17,3 0,3; L = 22,8 0,2 m, P ≤ 0,0001) e no número de ácinos (C = 7,0 0,2; L = 8,7 0,1, mm2; P ≤ 0,0002). As análises histomorfométrica juntamente com os resultados imuno-histoquímicos para PCNA sugerem que a leptina aumenta a proliferação celular. Em relação à expressão gênica, o tratamento de leptina aumentou a expressão de todos os genes, mas ER-α, em mais de 200 vezes em comparação com a expressão no grupo C. Em conclusão, neste trabalho mostramos que a leptina tem um efeito direto sobre a próstata de ratos adultos levando a um aumento na proliferação celular e na expressão gênica da aromatase, receptor de androgênio, nas isoformas dos receptores de leptina e receptores de estrogênios alfa e beta que são importantes para a fisiologia normal do tecido prostático / The aim of this study was to evaluate the effect of leptin administration on the ventral prostate lobe of adult rat. Twenty adult male rats were divided into 2 groups: L - animals were daily injected with 50 μL of leptin (8 g / 100 g BW, subcutaneous) for four days and C -animals received the same volume of saline solution. Lipid profile and testosterone serum levels were evaluated. The prostate ventral lobe was processed for histomorphometric analysis. Gene expression of aromatase, androgen receptor, leptin and estrogen receptors isoforms was evaluated by real-time PCR. Cell proliferation was evaluated by PCNA immunohistochemistry. Data were expressed as mean  standard error and analyzed by students t-test. Serum levels of cholesterol (C = 39.7 4.2; L = 55.2 4.2, mg / dL; P ≤ 0.02) increased and testosterone (C = 1.6 0.43; L = 0.6 0.15, ng / dL; P ≤ 0.03) decreased in L group. The histomorphometric analysis showed a reduction in cell density (C = 8868 242; L = 8211 210, mm2; P ≤ 0.04), in total (C = 0.24 0.026; L = 0.10 0.009, mm2; P ≤ 0.001) and in the internal acini areas (C = 0.16 0.009; L = 0.08 0.006, mm2; P ≤ 0.0002). On the other hand, there was an increase in the epithelial height (C = 17.3 0.3; L = 22.8 0.2, m; P ≤ 0.0001) and in the number of acini (C = 7.0 0.2; L = 8.7 0.1, mm2; P ≤ 0.0002). The histomorphometric analyses together with PCNA immunohistochemistry results suggest that leptin increases cell proliferation. In relation to the gene expression, leptin treatment increased the expression of all genes, but ER-α, in more than 200 times compared to the expression in C group. In conclusion, in this paper we showed that leptin has a direct effect on the prostate gland of adult rats leading to an increase in proliferation and in the gene expression of aromatase, androgen, leptin and estrogen receptors isoforms that are important for the physiology of the prostate gland.
19

Análise molecular e morfométrica da próstata ventral de ratos injetados com leptina / Molecular and morphometric analysis of rat ventral prostate injhecteo with leptins

Jorge Luiz Alves Pereira 07 March 2012 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O objetivo deste estudo foi avaliar o efeito da administração de leptina no lobo ventral da próstata de ratos adultos. Vinte ratos Wistar machos e adultos foram divididos em 2 grupos: L - animais foram injetados com 50 μL diária de leptina (8 μg / 100 g PC, subcutânea) durante quatro dias e C - animais receberam o mesmo volume de solução salina. Perfil lipídico e níveis séricos de testosterona foram avaliados. O lobo ventral da próstata foi processado para análise histomorfométrica. Expressão dos genes da aromatase, receptor de andrógeno, receptores de estrógeno (α e β) e as isoformas dos receptores de leptina longa (Ob-Rb) e curta (Ob-Ra) foram avaliados por PCR em tempo real. Proliferação celular foi avaliada por imuno-histoquímica com PCNA. Os dados foram expressos como média  erro padrão e analisados pelo teste t de Student. Níveis séricos de colesterol aumentaram (C = 39,7 4,2; L = 55,2 4,2, mg / dL, P ≤ 0,02) e de testosterona (C = 1,6 0,43; L = 0,6 0,15, ng / dL, P ≤ 0,03) diminuíram no grupo L. A análise histomorfométrica mostrou uma redução na densidade de células (C = 8868 242; L = 8.211 210, mm2; P ≤ 0,04), na área total (C = 0,24 0,026; L = 0,10 0,009, mm2; P ≤ 0,001) e na área interna dos ácinos (C = 0,16 0,009; L = 0,08 0,006, mm2; P ≤ 0,0002). Por outro lado, houve um aumento na altura do epitélio (C = 17,3 0,3; L = 22,8 0,2 m, P ≤ 0,0001) e no número de ácinos (C = 7,0 0,2; L = 8,7 0,1, mm2; P ≤ 0,0002). As análises histomorfométrica juntamente com os resultados imuno-histoquímicos para PCNA sugerem que a leptina aumenta a proliferação celular. Em relação à expressão gênica, o tratamento de leptina aumentou a expressão de todos os genes, mas ER-α, em mais de 200 vezes em comparação com a expressão no grupo C. Em conclusão, neste trabalho mostramos que a leptina tem um efeito direto sobre a próstata de ratos adultos levando a um aumento na proliferação celular e na expressão gênica da aromatase, receptor de androgênio, nas isoformas dos receptores de leptina e receptores de estrogênios alfa e beta que são importantes para a fisiologia normal do tecido prostático / The aim of this study was to evaluate the effect of leptin administration on the ventral prostate lobe of adult rat. Twenty adult male rats were divided into 2 groups: L - animals were daily injected with 50 μL of leptin (8 g / 100 g BW, subcutaneous) for four days and C -animals received the same volume of saline solution. Lipid profile and testosterone serum levels were evaluated. The prostate ventral lobe was processed for histomorphometric analysis. Gene expression of aromatase, androgen receptor, leptin and estrogen receptors isoforms was evaluated by real-time PCR. Cell proliferation was evaluated by PCNA immunohistochemistry. Data were expressed as mean  standard error and analyzed by students t-test. Serum levels of cholesterol (C = 39.7 4.2; L = 55.2 4.2, mg / dL; P ≤ 0.02) increased and testosterone (C = 1.6 0.43; L = 0.6 0.15, ng / dL; P ≤ 0.03) decreased in L group. The histomorphometric analysis showed a reduction in cell density (C = 8868 242; L = 8211 210, mm2; P ≤ 0.04), in total (C = 0.24 0.026; L = 0.10 0.009, mm2; P ≤ 0.001) and in the internal acini areas (C = 0.16 0.009; L = 0.08 0.006, mm2; P ≤ 0.0002). On the other hand, there was an increase in the epithelial height (C = 17.3 0.3; L = 22.8 0.2, m; P ≤ 0.0001) and in the number of acini (C = 7.0 0.2; L = 8.7 0.1, mm2; P ≤ 0.0002). The histomorphometric analyses together with PCNA immunohistochemistry results suggest that leptin increases cell proliferation. In relation to the gene expression, leptin treatment increased the expression of all genes, but ER-α, in more than 200 times compared to the expression in C group. In conclusion, in this paper we showed that leptin has a direct effect on the prostate gland of adult rats leading to an increase in proliferation and in the gene expression of aromatase, androgen, leptin and estrogen receptors isoforms that are important for the physiology of the prostate gland.
20

Leptina em fêmeas suínas: relação com status reprodutivo e causas de descarte / Leptin in swine females: relationship between reproductive status and culling causes

Moreira, Fabiana 22 November 2011 (has links)
Made available in DSpace on 2014-08-20T14:38:04Z (GMT). No. of bitstreams: 1 tese_fabiana_moreira.pdf: 1442913 bytes, checksum: 613ed46b361d675bfb046a7b74462171 (MD5) Previous issue date: 2011-11-22 / Leptin is a multifunctional peptidic hormone, primarily produced by the adipose tissue, which has receptors (Ob-Rs) in reproductive organs, hypothalamus and hypophysis, acting in the appetite regulation and energetic expenditure, potentially influencing the expression of the reproductive function, at puberty and lactation. Reproductive failure are the main causes for female culling, representing 30% to 40%,of the total female culling. Thus, post-mortem evaluation of the genital organs at slaughter may have an important diagnostic value, helping on the identification of the stage of female`s estrous cycle and aiding the interpretation of reproductive abnormalities. Its long form receptor (OBR-b) performs signal transduction in several cell types via mitogen- activated protein kinases (MAPK) cascade, such as ERK 1/2 and p38. The first stage of this thesis is aimed to evaluate the presence of leptin and MPAK in oocites of pubertal sows and prepubertal gilts. Ovaries from 10 pubertal sows and 10 prepubertal gilts were collected at a slaughterhouse. Slides were analyzed for the presence of oocites included in primordial/primary (OIPF), secondary (OISF) and tertiary follicles (OITF). Immunohistochemistry (IHC) was performed with polyclonal antibodies anti-leptin and anti-phospho-MAPK (ERK 1/2 and p38). The second stage involved 28 pubertal sows and the analyses were performed in hypothalamic neurons, endometrial glands and oocytes. For IHC, the antibodies were polyclonal anti-leptin and anti-leptin receptor. Responses were compared with reproductive data registered for each female. All images in both stages were analyzed by 16-Bit Histogram application from Image J® software. Immunolabeling for leptin and activated ERK 1/2 MAPK were more intense in sows oocytes (p ≤ 0.05), while the immunolabeling for activated p38 MAPK was more intense in gilts oocytes (p = 0.05). In sows, OIPF were more intensely marked for leptin and p38 MAPK (p <0.05), on the other hand, for gilts there was no difference in the marking of follicular oocytes from the analyzed categories. Hypothalamic neurons were more intensely marked in the sows culled by reproductive problems (p <0.05). The hypothalamus, uterus and oocytes of luteal or follicular phase sows showed more intense immunolabeling for leptin and OBR-b than the females with cystic ovaries. The immunolabeling for leptin was more pronounced in the hypothalamus and uterus of sows from parity order 2 group (PO 2-4) (p <0.05). These results demonstrate that leptin may be a marker for oocyte competence. Also, cyclic females having PO 2-4 presented more intense leptin immunolabeling in the hypothalamus and uterus and for OBR-b in the oocyte and uterus. The OBR-b immunolabeling was more pronounced in primiparous and multiparous females than for nulliparous. Therefore, immunolabeling for leptin and OBR-b can be a marker for reproductive performance in swine females. / A leptina é um hormônio peptídico multifuncional, produzido primariamente pelo tecido adiposo, com receptores (Ob-Rs) presentes em órgãos reprodutivos, hipotálamo e hipófise, que atua na regulação do apetite e no gasto energético, com potencial influência sobre a expressão da função reprodutiva, na puberdade e após a lactação. Desordens reprodutivas são as causas mais comuns, atribuídas ao total dos descartes, entre 30 e 40%. Considerando a alta proporção de descartes por estes problemas, a avaliação dos órgãos genitais no abate tem importante valor diagnóstico, auxiliando na identificação do estágio do ciclo estral da fêmea e na interpretação de possíveis anormalidades reprodutivas. O seu receptor de forma longa (OBR-b) realiza transdução de sinal em diversos tipos celulares via cascata das proteínas quinases ativadas por mitógenos (MAPK), tais como ERK 1/2 e p38. A primeira etapa do trabalho teve por objetivo avaliar a presença da leptina, e das MAPK nos oócitos de fêmeas suínas púberes e pré-púberes. Envolveu ovários de 10 fêmeas pré-púberes e 10 púberes coletados no abate e lâminas foram analisadas de oócitos inclusos em folículos primordiais/primários (OIFP), secundários (OIFS) e terciários (OIFT). Para a técnica de imuno-histoquímica (IHQ) os anticorpos policlonais instilados foram anti-leptina, anti-phospho- MAPK (ERK 1/2 e p38). A segunda etapa envolveu 28 porcas púberes descartadas, das quais foram analisados os neurônios do hipotálamo, glândulas endometriais e oócitos. Para a IHQ foram utilizados anticorpos policlonais anti-leptina e anti-receptor da leptina e objetivou comparar as respostas com os dados produtivos e reprodutivos a partir do registro de cada fêmea. Em ambas as etapas de trabalho foram utilizadas as modas obtidas pelo aplicativo 16 Bit-Histograma do software Image J®. A imunomarcação da leptina e a presença de ERK 1/2 ativada MAPK foram mais intensas em oócitos de porcas (p≤0,05), enquanto que a marcação para p38 MAPK ativada foi mais intensa em oócitos de leitoas (p=0,05). Em porcas, os OIFP estavam mais intensamente marcados para a leptina e p38 MAPK (p<0,05), mas para leitoas não foi observada diferença na marcação dos oócitos independente do estádio folicular. No hipotálamo a imunomarcação para a leptina foi mais intensa nas porcas descartadas por problemas reprodutivos (p<0,05). O hipotálamo, útero e oócitos das porcas que estavam na fase lútea ou fase folicular apresentaram imunomarcação para leptina e OBR-b mais acentuada que naquelas que possuíam cistos ovarianos. A imunomarcação para a leptina foi mais acentuada no hipotálamo e útero daquelas porcas do grupo ordem de parto 2 (OP 2-4) (p<0,05). Estes resultados demonstram que a leptina pode ser um dos marcadores para competência oocitária. Além disso, pode também ser observado que fêmeas cíclicas com OP 2-4 partos apresentam imunomarcação mais intensa para leptina no hipotálamo e útero, e OBR-b nos oócitos e útero. O OBR-b obteve marcação mais acentuada em fêmeas primíparas e multíparas, que nulíparas. Portanto, a imunomarcação para leptina e OBR-b podem ser um marcador de sinalização reprodutivo em fêmeas suínas.

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