Expression and regulation of estrogen-converting enzymes in ectopic human endometrial tissue.

OBJECTIVE: To investigate the regulation of estrogen-converting enzymes in human ectopic endometrial tissue. DESIGN: Animal study. SETTING: Academic medical center. ANIMAL(S): Sixty female nude mice with implanted human endometrial tissue. PATIENT(S): Twenty-two premenopausal women undergoing endometrial biopsy or hysterectomy. INTERVENTION(S): Human endometrial tissue was implanted into the peritoneal cavity of nude mice, and the effect of therapeutic drugs on transcription of steroid receptors and estrogen-converting enzymes was analyzed. MAIN OUTCOME MEASURE(S): Transcript levels of steroid hormone receptors, 17beta-hydroxysteroid dehydrogenase type 1 and 2, aromatase, and steroid sulfatase as well as proliferation rate were analyzed in the human ectopic endometrial tissue. RESULT(S): Steroid receptors and estrogen-converting enzymes were expressed in the ectopic human endometrial fragments. Application of medroxyprogesterone acetate, dydrogesterone, danazol, and the aromatase inhibitor finrozole significantly inhibited aromatase transcription. In addition, danazol caused a significant decrease in transcription of steroid sulfatase, and finrozole, of 17beta-hydroxysteroid dehydrogenase type 1 in parallel to a decrease in proliferation rate in the ectopic human endometrial tissue. CONCLUSION(S): Pharmacological regulation of transcription of estrogen-converting enzymes in human endometrium cultured in nude mice may help to develop new therapeutic concepts based on local regulation of estrogen metabolism in endometriosis.

Isolation and characterization of a cDNA encoding for a lysozyme from the gut of the reduviid bug Triatoma infestans.

We have isolated and characterised a Triatoma infestans cDNA encoding a lysozyme. A 174-bp fragment was amplified by PCR using degenerate oligodeoxyribonucleotide primers derived from the known amino acid sequences of lysozyme from other insects. This PCR fragment was used to screen a cDNA gut library of T. infestans. A clone containing the 3'-end of the lysozyme cDNA (219 bp) was isolated and sequenced. RACE was used to amplify the 5'-end of the lysozyme cDNA. After sequencing the complete lysozyme cDNA, the deduced 417 amino acid sequence showed high identity (40-50%) with other chicken-type lysozymes. The amino acid residues responsible for the catalytic activity and the binding of the substrate were essentially conserved. The expression pattern of the lysozyme gene in bugs at different molting and feeding states showed that this gene was upregulated in the digestive tract directly after the molt and after feeding. Additionally, this lysozyme gene was expressed differently in the different regions of the digestive tract, strongly in the cardia and stomach, the anterior regions of the midgut, and only traces of lysozyme mRNA could be detected in the small intestine, the posterior region of the midgut.