Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.1.17 (ornithine decarboxylase)
 6,351 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present review describes and discusses published results on growth and hormonal responsiveness of human endometrial stromal cells in culture. The proliferative potential of serially subcultured cells, that is, the number of cell doublings before cells enter mitotic senescence and cease to divide, was unusually high in stromal cells from several endometrial specimens, a property that may reflect the unique proliferative capacity of human endometrium when compared to other adult tissues. Fluorescent visualization of microfilaments revealed distinct age-related changes in the distribution of cytoskeletal fibers. Addition of ovarian steroids to the culture medium of stromal cells resulted in significant morphologic changes. From comparative studies using different culture media it became evident that medium components remarkably influenced cell morphology during early culture periods in an irreversible manner. Cultured stromal cells yielded interesting results in experiments designed to define the role of polyamines in growth regulation. Proliferation was greatly inhibited when polyamine levels were reduced by specific inhibition of ornithine decarboxylase, the first and rate limiting enzyme in polyamine synthesis which produces putrescine by catalytic conversion from ornithine. The antiproliferative effects were reversed by addition of putrescine to the culture medium. These results clearly establish a causal link between polyamine depletion and growth deficiencies and reveal an essential function of polyamines in stromal cell proliferation. Hormonally regulated parameters in cultured stromal cells include aromatase activity, pregnancy-associated plasma protein-A, 51K secreted protein, prolactin and laminin. The hormonally regulated production of prolactin and laminin, both considered markers of decidualization, together with morphologic changes of stromal cells to decidual-like cells, strongly suggest that human endometrial stromal cells, when subjected to appropriate hormonal stimulation, are capable of differentiating into decidual cells in culture. Cultured stromal cells therefore offer a unique opportunity to examine the complex changes in gene expression associated with decidualization. In addition, in vitro decidualization may prove to be an effective diagnostic tool in certain cases of infertility. Finally, decidualization of cultured stromal cells represents a relevant end point for testing compounds of potential clinical importance, such as synthetic progestins or antifertility drugs.
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PMID:Growth and hormonal responsiveness of human endometrial stromal cells in culture. 297 97

Infertility noted in two congenic strains of mice was associated with abortion, metritis, and stillbirths. Pasteurella pneumotropica was recovered from affected uterine tracts of ATL mice. Tetracycline treatment for 6 weeks was instituted in an attempt to minimize Pasteurella-associated infertility. Nine ATL mice and 12 ATH mice were examined 4 and 12 months after cessation of tetracycline therapy, respectively. Histopathologically, all animals appeared normal. P. pneumotropica was recovered from six of nine prepuces of both ATH and ATL mice; similarly, two of three vaginal culture of the ATL mice yielded this bacterium. Pasteurella ureae was isolated from three of eight reproductive tracts of the female ATH mice, Negative indole and ornithine decarboxylase reactions and positive acid production for mannitol differentiated P. ureae from P. pneumotropica. This report represents the first confirmed isolation of P. urea from animals. Biochemical profiles of atypical strains of P. pneumotropica isolated from animals are discussed and compared with those of P. ureae. The need for careful biochemical characterization of all Pasteurella isolated from rodents is emphasized.
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PMID:Isolation of Pasteurella ureae from reproductive tracts of congenic mice. 725 25

Polycystic ovary syndrome is a multi-system endocrinopathy with long-term metabolic and cardiovascular health consequences. Patients typically present due to symptoms of irregular menstruation, hair growth, or infertility; however, recent management options are aimed at further treating underlying glucose-insulin abnormalities as well as androgen excess for proactive control of symptoms. By a 2003 international consensus conference, diagnosis is made by two out of three criteria: chronic oligoovulation or anovulation after excluding secondary causes, clinical or biochemical evidence of hyperandrogenism (but not necessarily hirsutism due to inter-patient variability in hair follicle sensitivity), and radiological evidence of polycystic ovaries. Traditional medical treatment options include oral contraceptive pills, cyclic progestins, ovulation induction, and anti-androgenic medications (aldosterone antagonist, 5alpha-reductase antagonist, and follicle ornithine decarboxylase inhibitor). Recent pharmacotherapies include insulin-sensitizing medications metformin and two thiazolidinediones (rosiglitazone/Avandia and pioglitazone/Actos), a CYP19 aromatase inhibitor (letrozole/Femara), and statins to potentially lower testosterone levels.
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PMID:Contemporary medical therapy for polycystic ovary syndrome. 1701 Sep 75

Putrescine plays a very important role in the regulation of division, differentiation and maturation of cells as well as apoptosis. As the polycationic molecule it stabilizes the structure of DNA and participates in the functioning of cell membranes. It is able to interact with series of ion channels and has affinity for many receptors. The article presents the participation of putrescine in the metabolism of iron and mechanism of its transport across biological membranes. Especially important for the homeostasis of putrescine has ornithine decarboxylase and availability of its substrate--ornithine. Affecting to this enzyme is the simplest and widely used method of controlling the concentration of putrescine. For this purpose its inhibitor-eflornithine is applied. There was also a number of other enzymes involved in the metabolism of putrescine that was presented. Current information about the clinical relevance of putrescine in infertility, embryonic development, hirsutism, epilepsy, Alzheimer's disease, Parkinson's disease, prevention of metastases and hemostasis was also described. These processes were presented, in which putrescine plays a major role and focused on the latest reports. Attention was drawn to the situations where it has beneficial effects and those in which it is the cause of the pathology. Some of the cited reports are in phase of speculation on the possible use of it, but a significant part is already confirmed and used in clinical practice. The facts presented in this article show how great is the meaning of putrescine and how important role this simple specimen plays in the metabolic processes of living organisms.
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PMID:[The importance of putrescine in the human body]. 2486 91

The aging-related decline in fertility is an increasingly pressing medical and economic issue in modern society where women are delaying family building. Increasingly sophisticated, costly, and often increasingly invasive, assisted reproductive clinical protocols and laboratory technologies (ART) have helped many older women achieve their reproductive goals. Current ART procedures have not been able to address the fundamental problem of oocyte aging, the increased rate of egg aneuploidy, and the decline of developmental potential of the eggs. Oocyte maturation, which is triggered by luteinizing hormone (LH) in vivo or by injection of human chorionic gonadotropin (hCG) in an in vitro fertilization (IVF) clinic, is the critical stage at which the majority of egg aneuploidies arise and when much of an egg's developmental potential is established. Our proposed strategy focuses on improving egg quality in older women by restoring a robust oocyte maturation process. We have identified putrescine deficiency as one of the causes of poor egg quality in an aged mouse model. Putrescine is a biogenic polyamine naturally produced in peri-ovulatory ovaries. Peri-ovulatory putrescine supplementation has reduced egg aneuploidy, improved embryo quality, and reduced miscarriage rates in aged mice. In this paper, we review the literature on putrescine, its occurrence and physiology in living organisms, and its unique role in oocyte maturation. Preliminary human data demonstrates that there is a maternal aging-related deficiency in ovarian ornithine decarboxylase (ODC), the enzyme responsible for putrescine production. We argue that peri-ovulatory putrescine supplementation holds great promise as a natural and effective therapy for infertility in women of advanced maternal age, applicable in natural conception and in combination with current ART therapies.
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PMID:Can peri-ovulatory putrescine supplementation improve egg quality in older infertile women? 3046 17