scholarly journals Troglitazone, an Insulin-Sensitizing Thiazolidinedione, Represses Combined Stimulation by LH and Insulin of de Novo Androgen Biosynthesis by Thecal Cells in Vitro

2002 ◽  
Vol 87 (3) ◽  
pp. 1129-1133 ◽  
Author(s):  
Johannes D. Veldhuis ◽  
George Zhang ◽  
James C. Garmey

Polycystic ovarian syndrome (anovulatory hyperandrogenism) is marked by adolescent onset of systemic hyperinsulinism, oligoovulation, hirsutism, excessive LH and androgen secretion, and variable reduction in fertility. Insulin and LH are believed to act in concert to promote ovarian androgen hypersecretion in this disorder. Administration of troglitazone, an insulin-sensitizing agent and putative PPARγ agonist, can decrease hyperinsulinism, suppress T production, and ameliorate oligoovulation in some women with this endocrinopathy. The present study tests the hypothesis that troglitazone directly inhibits de novo androgen biosynthesis stimulated jointly by LH and insulin in primary cultures of (porcine) thecal cells. We show that troglitazone dose-dependently antagonizes LH/insulin’s combined stimulation of androstenedione and T production by thecal cells in vitro. Consistent steroidogenic inhibition of 80–95% was achieved at drug concentrations of 3–6.8 μm (P < 0.001). Exposure of thecal cells to the thiazolidinedione derivative also blocked bihormonally stimulated accumulation of CYP17 (cytochrome P450 17 α-hydroxylase/C17–20 lyase) gene expression, as reflected by decreased accumulation of cognate heterogeneous nuclear RNA and mRNA (by 30–65%; P < 0.05). Moreover, troglitazone suppressed LH/insulin-induced phosphorylation of the 52-kDa immunoprecipitated CYP17 enzyme by 88% (P < 0.001). A putative natural agonist of PPARγ nuclear transcription, 15-deoxy-δ-12,14-prostaglandin J2, also inhibited LH/insulin-driven androstenedione biosynthesis and CYP17 gene expression in thecal cells. In conclusion, a synthetic thiazolidinedione (troglitazone) and a natural ligand of PPARγ (15-deoxy-δ-12,14-prostaglandin J2) effectively impede the concerted stimulation by LH and insulin of in vitro thecal cell androgen production, CYP17 gene expression, and CYP17 protein phosphorylation. This ensemble of inhibitory actions on LH/insulin-stimulated steroidogenesis offers a plausible mechanistic basis for at least part of the observed clinical efficacy of troglitazone in mitigating androgen excess in women with polycystic ovarian syndrome.

2010 ◽  
Vol 2010 ◽  
pp. 1-3 ◽  
Author(s):  
Simone Giulini ◽  
Giulia Dante ◽  
Susanna Xella ◽  
Antonio La Marca ◽  
Tiziana Marsella ◽  
...  

We report a case of right adnexal torsion during pregnancy after an oocyte in vitro maturation and intracitoplasmic sperm injection cycle in patient with polycystic ovary syndrome. A 31-year-old woman with a typical clinical disorder of polycystic ovarian syndrome was included in an oocyte in vitro maturation program. Right adnexal torsion occurred two days after embryo transfer, and laparoscopy detorsion was successfully performed with preservation of adnexa. The patient had a full-term pregnancy and delivered a healthy infant at 40 weeks of gestation. To our knowledge this is the first report of adnexal torsion after an oocyte in vitro maturation and intracitoplasmic sperm injection program.


2021 ◽  
Vol 66 (1) ◽  
pp. 35-44
Author(s):  
Excel Rio S Maylem ◽  
Leon J Spicer ◽  
Isadora Batalha ◽  
Luis F Schutz

Asprosin is a novel fasting-induced protein encoded by fibrillin-1 (FBN1) gene, produced when FBN1 is cleaved by the enzyme furin, and is associated with insulin resistance and polycystic ovarian syndrome in humans. To characterize mRNA abundance of FBN1, FURIN, and the presumed asprosin receptor, olfactory receptor family 4 subfamily M member 1 (OR4M1) in granulosa (GC) and theca cells (TC), and identify hormones regulating FBN1 mRNA expression, GC and TC from small (1–5 mm; SM) and large (>8 mm; LG) follicles were collected from ovaries of heifers obtained at an abattoir and used for real-time PCR gene expression analysis or in vitro evaluation of hormone regulation and asprosin effects. SMTC had 151-fold greater (P < 0.05) FBN1 mRNA abundance than SMGC, and LGTC had 50-fold greater FBN1 mRNA than LGGC. In contrast, OR4M1 mRNA was 81-fold greater in SMGC than LGGC and did not differ from SMTC, but LGTC had 9-fold greater OR4M1 mRNA than LGGC. FURIN mRNA was 2.6-fold greater in SMTC than SMGC, but did not differ among follicular sizes. In cultured TC, leptin, insulin, LH, IGF1 and steroids did not affect FBN1 mRNA, but TGFB1 increased (P < 0.05) FBN1 mRNA by 2.2-fold; EGF and FGFs increased FBN1 mRNA by 1.3- to 1.5-fold. Asprosin enhanced LH-induced TC androstenedione production, reduced IGF1-induced TC proliferation, and had no effect on progesterone production. Developmental regulation of FBN1, FURIN and OR4M1 along with direct effects of asprosin on TC suggests that asprosin may be a novel regulator of ovarian follicular function.


2005 ◽  
Vol 17 (4) ◽  
pp. 423 ◽  
Author(s):  
E. Capobianco ◽  
A. Jawerbaum ◽  
M. C. Romanini ◽  
V. White ◽  
C. Pustovrh ◽  
...  

15-Deoxy-Δ12,14-prostaglandin J2 (15dPGJ2) is a peroxisome proliferator-activated receptor γ (PPARγ) ligand that regulates lipid homeostasis and has anti-inflammatory properties in many cell types. We postulated that 15dPGJ2 may regulate lipid homeostasis and nitric oxide (NO) levels in term placental tissues and that alterations in these pathways may be involved in diabetes-induced placental derangements. In the present study, we observed that, in term placental tissues from streptozotocin-induced diabetic rats, 15dPGJ2 concentrations were decreased (83%) and immunostaining for nitrotyrosine, indicating peroxynitrite-induced damage, was increased. In the presence of 15dPGJ2, concentrations of nitrates/nitrites (an index of NO production) were diminished (40%) in both control and diabetic rats, an effect that seems to be both dependent on and independent of PPARγ activation. Exogenous 15dPGJ2 did not modify lipid mass, but decreased the incorporation of 14C-acetate into triacylglycerol (35%), cholesteryl ester (55%) and phospholipid (32%) in placenta from control rats, an effect that appears to be dependent on PPARγ activation. In contrast, the addition of 15dPGJ2 did not alter de novo lipid synthesis in diabetic rat placenta, which showed decreased levels of PPARγ. We conclude that 15dPGJ2 modulates placental lipid metabolism and NO production. The concentration and function of 15dPGJ2 and concentrations of PPARγ were altered in placentas from diabetic rats, anomalies probably involved in diabetes-induced placental dysfunction.


2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Karen L. Leung ◽  
Smriti Sanchita ◽  
Catherine T. Pham ◽  
Brett A. Davis ◽  
Mariam Okhovat ◽  
...  

Abstract Background Normal-weight polycystic ovary syndrome (PCOS) women exhibit adipose resistance in vivo accompanied by enhanced subcutaneous (SC) abdominal adipose stem cell (ASC) development to adipocytes with accelerated lipid accumulation per cell in vitro. The present study examines chromatin accessibility, RNA expression and fatty acid (FA) synthesis during SC abdominal ASC differentiation into adipocytes in vitro of normal-weight PCOS versus age- and body mass index-matched normoandrogenic ovulatory (control) women to study epigenetic/genetic characteristics as well as functional alterations of PCOS and control ASCs during adipogenesis. Results SC abdominal ASCs from PCOS women versus controls exhibited dynamic chromatin accessibility during adipogenesis, from significantly less chromatin accessibility at day 0 to greater chromatin accessibility by day 12, with enrichment of binding motifs for transcription factors (TFs) of the AP-1 subfamily at days 0, 3, and 12. In PCOS versus control cells, expression of genes governing adipocyte differentiation (PPARγ, CEBPα, AGPAT2) and function (ADIPOQ, FABP4, LPL, PLIN1, SLC2A4) was increased two–sixfold at days 3, 7, and 12, while that involving Wnt signaling (FZD1, SFRP1, and WNT10B) was decreased. Differential gene expression in PCOS cells at these time points involved triacylglycerol synthesis, lipid oxidation, free fatty acid beta-oxidation, and oxidative phosphorylation of the TCA cycle, with TGFB1 as a significant upstream regulator. There was a broad correspondence between increased chromatin accessibility and increased RNA expression of those 12 genes involved in adipocyte differentiation and function, Wnt signaling, as well as genes involved in the triacylglycerol synthesis functional group at day 12 of adipogenesis. Total content and de novo synthesis of myristic (C14:0), palmitic (C16:0), palmitoleic (C16:1), and oleic (C18:1) acid increased from day 7 to day 12 in all cells, with total content and de novo synthesis of FAs significantly greater in PCOS than controls cells at day 12. Conclusions In normal-weight PCOS women, dynamic chromatin remodeling of SC abdominal ASCs during adipogenesis may enhance adipogenic gene expression as a programmed mechanism to promote greater fat storage.


2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
George Queiroz Vaz ◽  
Alessandra Viviane Evangelista ◽  
Cassio Alessandro Paganoti Sartorio ◽  
Maria Cecilia Almeida Cardoso ◽  
Maria Cecilia Erthal ◽  
...  

Background.The use of donated oocytes for in vitro fertilization treatment in patients with ovarian failure is universally recognized. But would patients with polycystic ovarian syndrome (PCOS) be a good choice for egg donation programs?Objective.Comparing the pregnancy rates of egg receptors from donor patients diagnosed with PCOS to receptors from donors without PCOS.Design.Retrospective cohort study.Methods.A total of 234 patients who had undergone egg reception program were separated into two groups: Group I, receptors from PCOS donors (n=36); Group II, receptors from donors without PCOS (n=198). Medical records were reviewed and the fertilization, implantation, and pregnancy rates were calculated.Results.PCOS patients had an average of 3.23 more oocytes retrieved, but there were no differences in the number of mature oocytes that were used for donation between the groups. We also observed that the number of transferred embryos was also not significantly different, as well as the fertilization and implantation rates. The clinical pregnancy rates were not significantly different: 28% and 26% in Group I and Group II, respectively.Conclusions.Women with PCOS should not be excluded from egg donation programs.


2007 ◽  
Vol 81 (8) ◽  
pp. 3949-3968 ◽  
Author(s):  
Sathish Sadagopan ◽  
Neelam Sharma-Walia ◽  
Mohanan Valiya Veettil ◽  
Hari Raghu ◽  
Ramu Sivakumar ◽  
...  

ABSTRACT In vitro Kaposi's sarcoma-associated herpesvirus (KSHV) infection of primary human dermal microvascular endothelial (HMVEC-d) cells and human foreskin fibroblast (HFF) cells is characterized by the induction of preexisting host signal cascades, sustained expression of latency-associated genes, transient expression of a limited number of lytic genes, and induction of several cytokines, growth factors, and angiogenic factors. Since NF-κB is a key molecule involved in the regulation of several of these factors, here, we examined NF-κB induction during de novo infection of HMVEC-d and HFF cells. Activation of NF-κB was observed as early as 5 to 15 min postinfection by KSHV, and translocation of p65-NF-κB into nuclei was detected by immunofluorescence assay, electrophoretic mobility shift assay, and p65 enzyme-linked immunosorbent assay. IκB phosphorylation inhibitor (Bay11-7082) reduced this activation significantly. A sustained moderate level of NF-κB induction was seen during the observed 72 h of in vitro KSHV latency. In contrast, high levels of ERK1/2 activation at earlier time points and a moderate level of activation at later times were observed. p38 mitogen-activated protein kinase was activated only at later time points, and AKT was activated in a cyclic manner. Studies with UV-inactivated KSHV suggested a role for virus entry stages in NF-κB induction and a requirement for KSHV viral gene expression in sustained induction. Inhibition of NF-κB did not affect target cell entry by KSHV but significantly reduced the expression of viral latent open reading frame 73 and lytic genes. KSHV infection induced the activation of several host transcription factors, including AP-1 family members, as well as several cytokines, growth factors, and angiogenic factors, which were significantly affected by NF-κB inhibition. These results suggest that during de novo infection, KSHV induces sustained levels of NF-κB to regulate viral and host cell genes and thus possibly regulates the establishment of latent infection.


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