Papillomavirus E6 oncoprotein up-regulates occludin and ZO-2 expression in ovariectomized mice epidermis.

We have studied the expression of the tight junction proteins (TJ) occludin, claudin-1 and ZO-2 in the epidermis of female mice. We observed a peak of expression of these proteins at postnatal day 7 and a decrease in 6 week-old mice to values similar to those found in newborn animals. We explored if the expression of the E6 oncoprotein from high-risk human papilloma virus type 16 (HPV16) in the skin of transgenic female mice (K14E6), altered TJ protein expression in a manner sensitive to ovarian hormones. We observed that in ovariectomized mice E6 up-regulates the expression of occludin and ZO-2 in the epidermis and that this effect was canceled by 17ß-estradiol. Progesterone instead induced occludin and ZO-2 over-expression. However, the decreased expression of occludin and ZO-2 induced by 17ß-estradiol in the epidermis was not overturned by E6 or progesterone. In addition, we employed MDCK cells transfected with E6, and observed that ZO-2 delocalizes from TJs and accumulates in the cell nuclei due to a decrease in the turnover rate of the protein. These results reinforce the view of 17ß-estradiol and E6 as risk factors for the development of cancer through effects on expression and mislocalization of TJ proteins.

Effects of metformin treatment on luteal phase progesterone concentration in polycystic ovary syndrome.

The causes of luteal phase progesterone deficiency in polycystic ovary syndrome (PCOS) are not known. To determine the possible involvement of hyperinsulinemia in luteal phase progesterone deficiency in women with PCOS, we examined the relationship between progesterone, luteinizing hormone (LH) and insulin during the luteal phase and studied the effect of metformin on luteal progesterone levels in PCOS. Patients with PCOS (19 women aged 18-35 years) were treated with metformin (500 mg three times daily) for 4 weeks prior to the test cycle and throughout the study period, and submitted to ovulation induction with clomiphene citrate. Blood samples were collected from control (N = 5, same age range as PCOS women) and PCOS women during the late follicular (one sample) and luteal (3 samples) phases and LH, insulin and progesterone concentrations were determined. Results were analyzed by one-way analysis of variance (ANOVA), Duncan's test and Karl Pearson's coefficient of correlation (r). The endocrine study showed low progesterone level (4.9 ng/ml) during luteal phase in the PCOS women as compared with control (21.6 ng/ml). A significant negative correlation was observed between insulin and progesterone (r = -0.60; P < 0.01) and between progesterone and LH (r = -0.56; P < 0.05) concentrations, and a positive correlation (r = 0.83; P < 0.001) was observed between LH and insulin. The study further demonstrated a significant enhancement in luteal progesterone concentration (16.97 ng/ml) in PCOS women treated with metformin. The results suggest that hyperinsulinemia/insulin resistance may be responsible for low progesterone levels during the luteal phase in PCOS. The luteal progesterone level may be enhanced in PCOS by decreasing insulin secretion with metformin.

Effects of metformin treatment on luteal phase progesterone concentration in polycystic ovary syndrome

The causes of luteal phase progesterone deficiency in polycystic ovary syndrome (PCOS) are not known. To determine the possible involvement of hyperinsulinemia in luteal phase progesterone deficiency in women with PCOS, we examined the relationship between progesterone, luteinizing hormone (LH) and insulin during the luteal phase and studied the effect of metformin on luteal progesterone levels in PCOS. Patients with PCOS (19 women aged 18-35 years) were treated with metformin (500 mg three times daily) for 4 weeks prior to the test cycle and throughout the study period, and submitted to ovulation induction with clomiphene citrate. Blood samples were collected from control (N = 5, same age range as PCOS women) and PCOS women during the late follicular (one sample) and luteal (3 samples) phases and LH, insulin and progesterone concentrations were determined. Results were analyzed by one-way analysis of variance (ANOVA), Duncan's test and Karl Pearson's coefficient of correlation (r). The endocrine study showed low progesterone level (4.9 ng/ml) during luteal phase in the PCOS women as compared with control (21.6 ng/ml). A significant negative correlation was observed between insulin and progesterone (r = -0.60; P < 0.01) and between progesterone and LH (r = -0.56; P < 0.05) concentrations, and a positive correlation (r = 0.83; P < 0.001) was observed between LH and insulin. The study further demonstrated a significant enhancement in luteal progesterone concentration (16.97 ng/ml) in PCOS women treated with metformin. The results suggest that hyperinsulinemia/insulin resistance may be responsible for low progesterone levels during the luteal phase in PCOS. The luteal progesterone level may be enhanced in PCOS by decreasing insulin secretion with metformin.

Alteraciones hormonales en melasma idiopático / Hormonal alterations in idiophatic melasma

En nueve pacientes con melasma idiopática se encontraron niveles bajos de gonadotropinas y altos niveles de estrógenos en la folicular, así como también niveles bajos de progesterona en la fase lútea, cuando se compararon con pacientes controles. Estos resultados estuvieron de acuerdo con observaciones previas de la melasma en estados caracterizados por altos niveles de estrógenos tales como el embarazo y el uso de anticonceptivos hormonales. Es posible que estos pacientes tengan moderada disfunción ovárica (subclínica). Ya que los estrógenos están involucrados en el proceso pigmentario, es posible que esta anormalidad esté relacionada a la patogénesis del melasma idiopático

Cuerpo lúteo deficiente análisis de 30 casos con embarazo clínico / Deficient corpus luteum: analysis of 30 cases with clinical pregnancy

El cuerpo lúteo deficiente (CLD) es una disfunción ovulatoria poco precisada pero real. Se menciona que su frecuencia oscila entre el 3 y 10 por ciento de las parejas estériles y de 30 a 40 por ciento de los abortos habituales. Forma parte del grupo de aberraciones ovulatorias junto con la lutenización in situ y el síndrome de folículo luteinizado no roto. Su diagnóstico se basa en la morfología endometrial y determinación de progesterona. El objetivo de éste trabajo es analizar 30 casos de CLS que lograron embarazos. El diagnóstico se realizó en base a determinación baja de progesterona sérica, biopsia de endometrio irregular o en desfase y todos los factores de esterilidad restantes normales. El promedio de la edad de la paciente fue de 36 años y de esterilidad de 3.1. El tratamiento consistió en la administración de citrato de clomifeno (CC)100 mg al día de hCG en 21 casos. CC sólo en 8 casos y asociado a bromocriptina en un caso (hiperprolactinemia concomitante); 26 embarazos llegaron a término, siete de ellos consoporte de progesterona exógena las primeras semanas. Hubieron tres abortos y un ectópico. Se incluye que con un estudio completo de esterilidad que sólo revele progesterona sérica baha y/o endometrio en desfase o irregular el diagnóstico de CLD es probable y debe tratarse de primera instancia con CC más hCG. La evolución de los embarazos es normal y de acuerdo a éstos resultados es poco aceptable la utilización de progesterona como soporte del embarazo.

Insuficiência luteínica: correlaçäo entre temperatura basal, biopsia de endométrio e dosagens hormonais / Luteal insufficiency: correlation between basal temperature, endometrium biopsy and hormonal dosages

Os autores fazem citaçöes da literatua, enfocando os aspectos propedêuticos e etiológicos da insuficiência de corpo lúteo onde por raciocínio lógico dedutivo, procuram emitir a idéia da possibilidade de a referida síndrome estar ligada a distúrbios da "inibina" ovariana e consideram ainda provável que seja estágio inicial da síndrome dos ovários policísticos. Além disso, apresentam o achado propedêutico da correlaçäo dos três métodos citados em suas pacientes, onde encontram a correlaçäo geral de 78,1% entre os mesmos. Enfatizam a necessidade da realizaçäo de uma propedêutica completa para o estabelecimento de perfeito diagnóstico