Disease relevance of Theca Cells

• CRH also affects androgen production by theca cells and may be involved in the pathogenesis of ovarian hyperandrogenism (OH) [1].
• In addition, the normal inhibin A and inhibin B production in the absence of estradiol precursors and estradiol provide insight into the selective dysfunction of the theca cells in autoimmune oophoritis [2].
• In the thecomas, P-450SCC and P-450(17 alpha) were positive in luteinized theca cells and in cells with vacuolated cytoplasm, while P-450AROM was not observed [3].
• Immunohistochemical and biochemical analysis of a human Sertoli-Leydig cell tumor: autonomous steroid production characteristic of ovarian theca cells [4].
• Follicular atresia was reflected by reduced granulosa cell responsiveness to FSH, theca cell hyperplasia and increased basal and LH-stimulated androgen production [5].

High impact information on Theca Cells

• A luteinizing dose of LH caused a cessation of proliferation in luteinizing granulosa cells while stimulating a limited proliferation of theca cells [6].
• Estradiol and FSH each acted on follicles at different stages of development to stimulate proliferative activity of both granulosa and theca cells [6].
• These results indicate that, depending upon the state of differentiation of granulosa and theca cells, estradiol, FSH and LH can stimulate or inhibit the ability of these cells to proliferate [6].
• Cultured human granulosa and theca cells did not contain mRNA for IL-1 beta or IL-1RA but did contain mRNA for IL-1R [7].
• LH acts on theca cells via cAMP ro regulate both P450scc and P450(17) alpha mRNA levels, leading to increased biosynthesis of androstenedione [8].

Biological context of Theca Cells

• Our analysis revealed that PCOS theca cells have a gene expression profile that is distinct from normal theca cells [9].
• The molecular phenotype of polycystic ovary syndrome (PCOS) theca cells and new candidate PCOS genes defined by microarray analysis [9].
• In luteal phase, cortical stroma was negative or only weakly positive, whereas glycodelin was present in theca interna of the corpus luteum and luteinized granulosa cells and also in corpus albicans and Leydig cells of the ovarian hilus [10].
• We investigated the mechanism of lysophosphatidic acid (LPA) signaling in ovarian theca cells and observed that stimulation with this bioactive lipid markedly enhanced Thr/Tyr phosphorylation of the MAPK ERK1/2 [11].
• This demonstrates that in the absence of GDF-9, the follicles are incompetent to emit a signal that recruits theca cell precursors to surround the follicle; 2) The primary follicles of GDF-9-deficient mice demonstrate an up-regulation of kit ligand and inhibin-alpha [12].

Anatomical context of Theca Cells

• However, although normally a major HSPG of basement membranes or basal laminae, in chicken follicles, perlecan is absent from the membranous structure between the theca interna and granulosa cell layers, which to date has been considered a bona fide basement membrane [13].
• Rather, the protein is localized in the extracellular matrix of theca externa cells, which produce this HSPG [13].
• In PCOS ovaries, we found strong expression of EG-VEGF mRNA in theca interna and stroma in most of the specimens examined, thus spatially related to the new blood vessels [14].
• These autoantibodies were completely absorbed with powdered adrenal cortex and thus were "steroidal cell" antibodies (SCA), cross-reactive with a cytosolic antigen in the steroid-producing cells of adrenal cortex, placental syncytiotrophoblast, Leydig areas of testis, and theca interna/granulosa layer of ovarian follicles [15].
• GHR mRNA was not detected in preantral follicles, theca interna, theca externa, oocytes, or stroma [16].

Associations of Theca Cells with chemical compounds

• A hallmark of PCOS is excessive theca cell androgen secretion, which is directly linked to the symptoms of PCOS [9].
• We demonstrated that retinoic acid and GATA6 increased the expression of 17alpha-hydroxylase, providing a functional link between altered gene expression and intrinsic abnormalities in PCOS theca cells [9].
• Progesterone (P4), 17alpha-hydroxyprogesterone (17OHP4), and testosterone (T) production per cell were markedly increased in PCOS theca cell cultures [17].
• To test the hypothesis that the hyperandrogenemia associated with polycystic ovary syndrome (PCOS) results from an intrinsic abnormality in ovarian theca cell steroidogenesis, we examined steroid hormone production, steroidogenic enzyme activity, and mRNA expression in normal and PCOS theca cells propagated in long-term culture [17].
• PCOS theca cells were capable of substantial metabolism of precursors into T, reflecting expression of an androgenic 17beta-hydroxysteroid dehydrogenase [17].

Gene context of Theca Cells

• The Insl3 gene (originally designated Ley I-L), a member of the insulin-like superfamily, is specifically expressed in Leydig cells of the fetal and postnatal testis and in theca cells of the postnatal ovary [18].
• Immunohistochemical analysis also showed gonadotropin induced Egr-1 in theca cells [19].
• Alterations in mitogen-activated protein kinase kinase and extracellular regulated kinase signaling in theca cells contribute to excessive androgen production in polycystic ovary syndrome [20].
• The major findings of our studies are as follows: 1) There are no detectable signals around GDF-9-deficient follicles for several theca cell layer markers [i.e. 17alpha-hydroxylase, LH receptor (LHR), and c-kit, the receptor for kit ligand] [12].
• OBJECTIVE: The objective of the study was to explore mechanisms by which GATA6 mRNA levels are increased in PCOS theca cells [21].

Analytical, diagnostic and therapeutic context of Theca Cells

• Treatment of cell cultures with forskolin (25 microM) induced IL-1 beta transcripts in granulosa but not theca cells [7].
• In this present study, we carried out microarray analysis to define the gene networks involved in excess androgen synthesis by the PCOS theca cells in order to identify candidate PCOS genes [9].
• Localization of renin gene expression to monkey ovarian theca cells by in situ hybridization [22].
• RT-PCR analysis revealed that theca cells also express another AKR, 20 alpha HSD (AKR1C1) [23].
• By immunohistochemistry, ephrin B1 was moderately expressed on theca interna cells, but was expressed at a low level on granulosa cells in the preovulatory follicles [24].

References