Congenital Hypothyroidism is Associated With Impairment of the Leptin Signaling Pathway in the Hypothalamus in Male Wistar Animals in Adult Life.

The goal of this study is to investigate whether congenital hypothyroidism induced by MMI during gestation (G) or gestation plus lactation (GL) would affect the leptin action upon body weight control on hypothalamus. Six to eight pups per group were killed at 90 days of age. For statistical analysis one-way ANOVA followed by the Holm-Sìdak post hoc test was used. Hypothyroidism resulted in a significant increase in leptin serum levels in G 20% and GL 25% (p<0.04). There was a significant expression decrease of OBR in G 45% and GL 63%; pSTAT3 in G 56% and GL 51%; pERK in G 50% and GL 48%; POMC in G 41% and GL 46% (p<0.04), while a significant increase was assigned to SOCS3 in G 52% and GL 170% (p<0.04) protein expression. We can conclude that hypothyroxinemia condition in rats on adulthood results in impairment of the leptin signaling pathway via ObRb-STAT3 in the hypothalamus, which is likely to be involved in the leptin resistance.

Hormonal and testicular changes in rats submitted to congenital hypothyroidism in early life.

The goal of this study was to evaluate the influence of hypothyroidism induced by MMI, during gestation (G) or gestation plus lactation (GL) on testis and its relation with leptin in rats. Six to eight pups were killed at 90 days of age. For statistical analysis One-way ANOVA followed by the Holm-Sìdak post hoc test was used. Hypothyroidism resulted in a significant reduction in LH, FSH and testosterone and an increase in leptin serum levels (p < 0.04). There was a significant decrease in StAR, AR, FSHR, LHR, pSTAT3 and SOCS3 (p < 0.04) protein expression and in the fertility parameters (p < 0.04). We can conclude that hypothyroidism is associated with reduction of steroidogenesis and spermatogenesis leading to a low fertility potential in these animals. This outcome could be a consequence of low pituitary stimulus and testicular response and probably are not related with leptin hormone since its signaling pathway is down-regulated in the testis.

A link between hypothyroidism, obesity and male reproduction.

Hypothyroidism is a condition in which the serum levels of thyroid hormones are below that necessary to carry out physiological functions in the body. Hypothyroidism is related to obesity as an increase in body weight gain is seen in hypothyroid patients. Moreover, an inverse correlation between free thyroxine values and body mass index has been reported. Leptin, a polypeptide hormone produced by adipocytes, was originally thought to be an antiobesity hormone due its anorexic effects on hypothalamic appetite regulation. However, nowadays it is known that leptin conveys information about the nutritional status to the brain being considered a crucial endocrine factor for regulating several physiological processes including reproduction. Since the identification of thyroid hormone and leptin receptors on the testes, these hormones are being recognized as having important roles in male reproductive functions. A clear link exists among thyroid hormones, leptin and reproduction. Both hormones can negatively affect spermatogenesis and consequently may cause male infertility. The World Health Organization (WHO) estimates the overall prevalence of primary infertility ranging from 8 to 15%. The fact that 30% of couples' inability to conceive is related to a male factor and that the longer hypothyroidism persisted, the greater the damage to the testes, strongly suggest that more studies attempting to clarify both hormones actions directly in the testes need to be conducted specially in cases of congenital hypothyroidism. Therefore, the goal of this review is to highlight the relationship of such hormones in the reproductive system.

Leptin, its receptor and aromatase expression in deep infiltrating endometriosis.

BACKGROUND: The aim of this study was to evaluate the leptin levels in the serum and peritoneal fluid (PF) and the protein expression in three different peritoneal ectopic implants in patients who underwent surgery for deep infiltrating endometriosis. METHODS: All patients had been treated at the Department of Gynecology of the Pedro Ernesto University Hospital, Rio de Janeiro. The study group consisted of 15 patients who underwent surgery for adnexal masses and infertility, while the control group consisted of ten women who underwent surgery for tubal ligation. Peritoneal fluid and samples tissues were collected during surgery. Serum samples were obtained before anesthesia. In this study, the leptin levels in the serum and peritoneal fluid (PF) were evaluated by ELISA. The protein expression of leptin and its receptors (ObR) and aromatase enzyme were evaluated by Western blot analysis of the intestine, uterosacral ligament and vaginal septum in the ectopic implants. The t-test and one-way ANOVA with Holm-Sìdak post-test were used, and p < 0.05 was considered to be statistically significant. RESULTS: Compared to the controls, the serum leptin levels (control = 14.7 ng/mL ± 2.63, endometriosis = 19.2 ng/mL ± 1.84, p < 0.0001) were increased, while in PF, there was no difference (control = 6.68 ng/mL ± 0.43, endometriosis = 7.71 ng/mL ± 0.59, p = 0.18). Comparing women with and without ovarian implants, the leptin levels in both the serum and PF were significantly higher in women without ovarian implants (serum: with ovarian implant = 15.85 ± 1.99; without ovarian implant = 23.14 ± 2.60; ng/mL, p = 0.04; PF: with ovarian implant = 4.28 ± 1.30; without ovarian implant = 11.18 ± 2.98;ng/mL, p = 0.048). The leptin, ObR and aromatase protein expression levels were increased in lesions in the vaginal septum and were decreased in the intestine lesions. CONCLUSION: This study reports several interesting associations between the leptin levels in serum, peritoneal fluid, and tissue samples and the localization of the ectopic endometrium. Although this study does not provide a clear picture of the role of leptin in the development and progression of peritoneal implants, it contributed new data that might be useful to elucidating the enigma that is the role of leptin in endometriosis disease.

The testis of the mice C57/BL6 offspring in adulthood have alterations due to maternal caffeine consumption.

PURPOSE: To investigate the effects of the maternal caffeine consumption during pregnancy to adult male testis mice offspring. METHODS: Twenty pregnant mice were divided into control group (c) and caffeine group (cf). dams received daily saline or 20 mg/kg of caffeine subcutaneously. Male offspring were monitored daily until 13th week. The testis were used to evaluate both the proliferation (pcna) and apoptosis (bax); leptin receptor (ob-r); aromatase; follicle stimulating hormone (fshr), luteinizing hormone (lhr) and androgen receptors (ar); steroidogenic acute regulatory protein (star); vascular endothelial growth factor (vegf) and estrogen receptors (erα and erß) by western blotting. Serum concentrations of testosterone, estradiol and leptin were measured. RESULTS: There was a significant reduction in food intake and the body mass gain (p<0.05) in the cf ; pcna (p=0.01), fshr (p=0.02), star (p=0.0007), vegf (p=0.009), ar (p=0.03) in the cf. while an increase were note in bax (p=0.01), ob-r (p=0.02), lhr (p=0.04) and in the aromatase (p=0.03) in the cf. only erα and erß were not changed by maternal caffeine. The serum testosterone levels in the cf offspring were 90% lower than in the c offspring (p=0.04). CONCLUSION: Maternal caffeine consumption has a role and alters the testis of the offspring in adulthood.

The testis of the mice C57/BL6 offspring in adulthood have alterations due to maternal caffeine consumption

To investigate the effects of the maternal caffeine consumption during pregnancy to adult male testis mice offspring. METHODS: Twenty pregnant mice were divided into control group (c) and caffeine group (cf). dams received daily saline or 20 mg/kg of caffeine subcutaneously. Male offspring were monitored daily until 13th week. The testis were used to evaluate both the proliferation (pcna) and apoptosis (bax); leptin receptor (ob-r); aromatase; follicle stimulating hormone (fshr), luteinizing hormone (lhr) and androgen receptors (ar); steroidogenic acute regulatory protein (star); vascular endothelial growth factor (vegf) and estrogen receptors (erα and erβ) by western blotting. Serum concentrations of testosterone, estradiol and leptin were measured. RESULTS: There was a significant reduction in food intake and the body mass gain (p<0.05) in the cf ; pcna (p=0.01), fshr (p=0.02), star (p=0.0007), vegf (p=0.009), ar (p=0.03) in the cf. while an increase were note in bax (p=0.01), ob-r (p=0.02), lhr (p=0.04) and in the aromatase (p=0.03) in the cf. only erα and erβ were not changed by maternal caffeine. The serum testosterone levels in the cf offspring were 90% lower than in the c offspring (p=0.04). CONCLUSION: Maternal caffeine consumption has a role and alters the testis of the offspring in adulthood.

Leptin regulates gonadotropins and steroid receptors in the rats ovary.

The leptin hormone is important to satiety and an important link between the nutritional status and reproductive processes. Owing to the contradictory effects of leptin on the ovary and the failure to clarify the precise mechanism by which leptin affects the ovary, our aim was to contribute to evaluation if leptin can directly regulate the gene expression of leptin itself and its receptors, and the expression of several genes related to the ovary function by a model of tissue culture. Ovaries from Wistar dams were used at 90 days of age and were submitted to medium with presence and absence of leptin. The results can demonstrate that leptin regulates gonadotropins and steroid receptors, which could suggest that the ovarian leptin role could be secondary to the changes in these receptors expression in rats.

La hormona leptina es importante en la sensación de la saciedad y un vínculo importante entre el estado nutricional y los procesos reproductivos. Debido a los efectos contradictorios de la leptina en el ovario y la falta de esclarecimiento del mecanismo exacto por el cual la leptina afecta el ovario, nuestro objetivo es contribuir a la evaluación si la leptina puede regular directamente la expresión del gen de la leptina sí mismo y sus receptores, y la expresión de varios genes relacionados con la función del ovario por un modelo de cultivo de tejidos. Los ovarios de las presas Wistar fueron usadas en los 90 días de edad y se sometieron a medio con presencia y ausencia de leptina. Los resultados pueden mostrar que la leptina regula las gonadotropinas y los receptores de esteroides, lo que podría sugerir que la función ovárica de la leptina podría ser secundario a los cambios en la expresión de sus receptores en ratas.

Leptin regulates gonadotropins and steroid receptors in the rats ovary / La leptina regula las gonadotropinas y los receptores de esteroides en el ovario de las ratas

The leptin hormone is important to satiety and an important link between the nutritional status and reproductive processes. Owing to the contradictory effects of leptin on the ovary and the failure to clarify the precise mechanism by which leptin affects the ovary, our aim was to contribute to evaluation if leptin can directly regulate the gene expression of leptin itself and its receptors, and the expression of several genes related to the ovary function by a model of tissue culture. Ovaries from Wistar dams were used at 90 days of age and were submitted to medium with presence and absence of leptin. The results can demonstrate that leptin regulates gonadotropins and steroid receptors, which could suggest that the ovarian leptin role could be secondary to the changes in these receptorse expression in rats (AU)

La hormona leptina es importante en la sensación de la saciedad y un vínculo importante entre el estado nutricional y los procesos reproductivos. Debido a los efectos contradictorios de la leptina en el ovario y la falta de esclarecimiento del mecanismo exacto por el cual la leptina afecta el ovario, nuestro objetivo es contribuir a la evaluación si la leptina puede regular directamente la expresión del gen de la leptina sí mismo y sus receptores, y la expresión de varios genes relacionados con la función del ovario por un modelo de cultivo de tejidos. Los ovarios de las presas Wistar fueron usadas en los 90 días de edad y se sometieron a medio con presencia y ausencia de leptina. Los resultados pueden mostrar que la leptina regula las gonadotropinas y los receptores de esteroides, lo que podría sugerir que la función ovárica de la leptina podría ser secundario a los cambios en la expresión de sus receptores en ratas (AU)