Terapia hormonal na menopausa: quando não usar: [revisão] / Hormone therapy in menopause: when not to use: [review]

A menopausa corresponde à cessação permanente da menstruação, conseqüente à perda da função folicular ovariana ou à remoção cirúrgica dos ovários. A idade média para ocorrência da menopausa natural gira em torno de 50 anos. A deficiência estrogênica decorrente da menopausa está associada com sintomas vasomotores, atrofia urogenital, declínio cognitivo, assim como a um aumento no risco de doenças crônico-degenerativas, aterosclerose e doença cardiovascular, osteoporose e doença de Alzheimer. A estrogenioterapia permanece sendo o tratamento mais efetivo para o manejo dos sintomas vasomotores e atrofia urogenital. Em mulheres com útero presente, a progesterona natural ou os progestogênios devem ser associados ao tratamento com estradiol para antagonizar os efeitos proliferativos deste hormônio sobre o endométrio e anular o risco de hiperplasia/carcinoma endometrial. Por outro lado, em determinadas condições clínicas, a terapia hormonal não é recomendada ou é mesmo contra-indicada. Neste artigo, focalizamos criticamente essas situações clínicas em que não se deve indicar a terapia hormonal na menopausa.

Menopause is defined as the permanent cessation of menses, as a result of the loss of ovarian follicular function or of surgical removal of ovaries. The mean age for occurrence of natural menopause is around 50 years. Estrogen deficiency has been associated with vasomotor symptoms, urogenital atrophy, and cognitive impairment, as well as increased risk of chronic degenerative diseases such as osteoporosis and Alzheimer’s disease. Estrogen therapy remains the most effective treatment for the management of vasomotor symptoms and urogenital atrophy. Progesterone or progestins should be added to estrogen treatment in women with uterus, in order to antagonize the estrogen-induced endometrial proliferation. In turn, in specific clinical conditions hormone therapy is not recommended. In the present article, the authors critically focus these clinical conditions in which hormone therapy should not be used.

Regulation of cadmium induced porphyria by ascorbic acid in chick embryos.

Sublethal doses of cadmium chloride (2.5, 5.0 and 10.0 mu mole/kg egg weight) were found to significantly alter the first two rate limiting enzymes of heme biosynthesis in chick embryos. Delta-aminolevulinic acid synthase activity was elevated by 2.05 and 2.11 fold with 5.0 and 10.0 mu moles of cadmium treatment respectively. However, this was reduced to 1.25 and 1.3 fold by the simultaneous administration of ascorbic acid. Blood delta-aminolevulinic acid dehydratase (ALA-D) activity was decreased by 48.4 and 55.0 per cent with 5.0 and 10.0 mu moles cadmium treatment respectively; in the presence of ascorbic acid only 18 and 24 per cent inhibition of ALA-D activity was observed. Further 1.39 and 2.08 fold accumulation of delta-aminolevulinic acid and 4.17 and 4.62 fold increase of blood porphyrins was observed in chick embryos treated with 5.0 and 10.0 mu moles cadmium respectively. This elevation of intermediate compounds of heme biosynthesis was effectively checked by the administration of ascorbic acid. Depletion of hepatic heme and free sulfhydryl level by cadmium were countered by the treatment of ascorbic acid. Hence, the present findings suggest the protective role of ascorbic acid against cadmium induced chemical porphyria in chick embryos.

Porfiria intermitente aguda: relato de um caso / Acute intermittent porphyria: case report

As porfirias sao doencas associadas a anormalidades na biossintese da heme, podendo ser adquiridas ou herediatarias. A porfiria intermitente aguda e uma forma hereditaria, de transmissao autossomica dominante, que apresenta, como defeito enzimatico basico, a deficiencia da sintetase do uroporfirinogenio I. Seu quadro clinico pode ser desencadeado por drogas, jejum prolongado, infeccoes e etanol, sendo caracterizado por sintomas neuropsiquiatricos e abdominais. O prognostico da doenca tem sido favoravel na maioria dos casos, embora o tratamento seja em geral inespecifico. No caso em questao a paciente apresentou quadro clinico compativel, provavelmente desencadeado pelo uso de anticoncepcionais orais, evidenciando melhora atraves de medidas gerais utilizadas, embora com recidiva posterior sem fator desencadeante

Effect of ursodeoxycholic acid on experimental hepatic porphyria induced by griseofulvin

Griseofulvin(GF) has become the drug of choice as an antifungal agent for patients who suffer from many kinds of fungal infection. In order to clarify hepatic injury by griseofulvin(GF) overload and the effect of UDCA on GF-induced hepatic injury, the authors carried out biochemical, histologic, and ultrastructural studies of liver following treatment with griseofulvin and ursodeoxycholic acid(UDCA) in mice. Urine porphobilinogen excretion in the group treated with GF alone was significantly increased and reached the highest level in the 4th week and declined thereafter. Biochemical studies of the liver function showed no remarkable changes of serum bilirubin levels throughout the experimental period in all groups, except for SGPT and alkaline phosphatase activities which were significantly elevated and reached the highest level in the second week. Then they slightly decreased in GF treated groups(GF alone and GF plus UDCA) in comparison with the control group. Pathologic findings in the group treated with GF alone include focal liver cell necrosis(esp, zone 3), Mallory bodies in hepatocytes(esp, zone 1), Kupffer cell activation, and brown protoporphyrin pigments in the hepatocytes, bile canaliculi and interlobular bile ducts with a marked inflammatory cell infiltration in the portal tracts. Under the polarizing light microscope, bile ductular and canalicular thrombi showed a "Maltese cross" birefringence in mice treated with GF alone. There is no definite finding of fatty change in hepatocyte. Under the microscope, the liver appeared normal with an intact lobular architecture in the GF plus UDCA treated group. Electron microscopically, GF-induced changes include swelling of mitochondria, globular protoporphyrin crystals in the hepatocyte cytoplasm, markedly dilated bile cannaliculi and bile ducts and the formation of a Mallory hyaline bodies in the hepatocytes. There were no noticeable structural changes in the GF plus UDCA-treated group. Therefore the results suggest that GF causes hepatic injury, namely porphyria and cholestasis, and the treatment of UDCA may have cytoprotective and choleretic effects on GF-induced hepatic injuries.

Evaluacion de la capacidad de la desferrioxamina para revertir una severa porfiria inducida por hexaclorobenceno / Evaluation of desferrioxamine capacity to revert a severe porphyrid induced by hexachlorobenzene

El objeto del presente trabajo es investigar la capacidad de la desferrioxamina (DF) como quelante de hierro para disminuir o revertir una porfiria experimental severa inducida por hexaclorobenceno (HCB) en ratas. La DF se comienza a administrar después de 17 semanas de intoxicación con HCB y se continúa hasta la semana 27. Se cuantifican semanalmente excreciones en orina de ácido aminolevúlico (ALA), profobilinógeno y porfirinas. Al final del experimento se sacrifican los animales y se determinan porfirinas hepáticas y actividad de ALA sintetasa y porfirinógeno carboxi-liasa. Los resultados indican que el quelante adminsitrado no mejora el disturbio provocado por el HCB sobre el camino metabólico del hemo en las presentes condiciones. Se comparan estos resultados con los obtenidos cuando la DF se da conjuntamente con el HCB desde el comienzo de la administración del fungicida, situación en que sí el quelante retarda y atenúa el efecto porfirinogénico del HCB. Se discute el papel del hierro en la metabolización del HCB

The role of iron in the hexachlorobenzine induced porphyria: I. Studies on diferent types of iron and its relation with porphyrinogen carboxy-lyase decrease

Se llevaron a cabo estudios para elucidar si en la porfiria por hexaclorobenceno (HCB) están alterados los contenidos de hierro total, no hémico en hígado y si existe alguna relación entre estas alteraciones y el decrenento de la porfirinógeno carboxi-liasa (PCL) hepática en ratas tratadas con la droga. Se observó que en los hígados porfíricos los niveles de hierro total y no hémico incrementaron significativamente como consecuencia de la intoxicación por HCB, mientras que este tratamiento produjo un decremento no significativo en el contenido de hierro hémico. Preparaciones enzimáticas de hígados porfíricos filtradas a través de columnas de Sephadex G-25, que separan el hierro libre y que tienen un contenido de hierro-proteína mayor que las normales, exhibieron una fuerte inhibición de PCL. Agentes quelantes, alfa alfa' bipiridilo y 8-hidroxiquinolina, no revierten tal inhibición. Se ensayó también el efecto in vitro de diferentes concentraciones de hierro inogánico, ferritina y hemina sobre la actividad de PCL normal. Así se observó que hierro inogánico y hemina producen ligera inhibición de PCL cuando se añaden en concentraciones mayores que las correspondientes a un hígado porfírico (0.08 mM y 10-6 M respectivamente como promedio en el medio de incubación). Por lo tanto dichas inhibiciones no tienen significado fisiológico. La ferritina no modifica el proceso de descarboxilación. De estos resultados surge que el hierro no desempeña un papel directo en el decremento de la actividad PCL en la porfiria experimental por HCB, no siendo el inhibidor que se pone de manifiesto en los ensayos de calentamiento. El hierro podría quizás estimular la metabolización del HCB dando origen a metabolitos activos