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P Tuohimaa

Publications and source records attributed to P Tuohimaa.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Role of sex steroids in development of anxiety in female mice].

Level of sex steroid hormones being changed throughout an estrous cycle influences physiological and behavioral features of female subjects. To test how estrogen and progesterone affect the anxiety level in mice the ovariectomy (OVX) followed by hormone treatment was carried out. After 1 week of recovery period estradiol benzonate (20 micrograms, s/c) was injected once a day during 7 consequent days. By the 7th day in addition to EB injection progesterone (500 micrograms, s/c) was also injected. Four hours later the mice were tested in elevated plus-maze to measure the anxiety level. Control animals were treated with sesame oil only. Behavioral data obtained demonstrate that the hormonal treatment altered anxiety state in experimental animals. In plusmaze paradigm, it has been demonstrated that progesterone-treated mice revealed the lowest level of open arm activity. In contrast, these mice showed the highest grooming activity as compared to other experimental groups. Immunohistochemical data on progesterone receptor (PR), immunoreactivity in brain have shown that the manipulation with different hormonal treatments modified the number of PR-ir cells in many brain areas. Our data suggest that sex steroid hormones play an important role in induction of anxiety level, as measured by elevated plus-maze, and this action might be partially mediated through the classical steroid receptors.

Animals↗
PubMed2000

Vitamin D induced up-regulation of keratinocyte growth factor (FGF-7/KGF) in MCF-7 human breast cancer cells.

Keratinocyte growth factor (FGF-7/KGF) is a secreted member of the fibroblast growth factor family, which functions primarily as an important paracrine mediator of cell growth and differentiation. Inhibitory pathways of vitamin D may also involve participation of some growth factors. To determine whether vitamin D may play a role in the expression of FGF-7, we investigated FGF-7 expression in human breast cancer cells treated with 1,25-dihydroxyvitamin D3, which inhibited the growth of the cells. By means of cDNA microarray, RT-PCR, and Western blot analysis, we have shown an increase in expression of FGF-7 on both mRNA and protein levels after vitamin D exposure. This is the first demonstration of vitamin D regulation of FGF-7 expression and its possible involvement in mediating growth and differentiation by vitamin D.

Base Sequence↗
PubMed2000

Androgen receptor and vitamin D receptor in human ovarian cancer: growth stimulation and inhibition by ligands.

The data suggest that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and androgens are essential for regulation of growth and differentiation in, e.g., human reproductive tissues. We investigated the possible cross-talk between 1,25(OH)2D3 and androgens in the human ovarian cancer cell line OVCAR-3. Our data demonstrate that 1,25(OH)2D3 and androgen (dihydrotestosterone, DHT) regulate the growth of OVCAR-3 cells. Nine days' treatment of OVCAR-3 cells with 100 nM DHT resulted in 48% stimulation of growth, whereas growth inhibition (73%) was observed after treatment with 100 nM 1,25(OH)2D3. The combination of 1,25(OH)2D3 and DHT showed that 1,25(OH)2D3 clearly reduces the growth-stimulatory effect of DHT on OVCAR-3 cells. Moreover, Western blot analysis revealed that these cells contain receptors for 1,25(OH)2D3 (VDR) and androgen (AR). Expression of VDR and AR was up-regulated by their cognate ligands. Up-regulation of AR by 1,25(OH)2D3 and of VDR by DHT provides evidence of cross-talk between 2 signaling pathways in OVCAR-3 cells. We also studied the immuno-histochemical distribution of VDRs and ARs in rat ovaries and human ovarian cancer cases. In rat ovaries, VDRs were observed mainly in granulosa and theca cells and ARs in granulosa cells and surface epithelium. In the human ovarian cancer cases studied, 43% were VDR-positive and 64% AR-positive. Combining the results suggests that the growth of ovarian tissue might be regulated by 1,25(OH)2D3 and androgen.

Adenocarcinoma↗
PubMed2000

Prostate cancer risk and prediagnostic serum 25-hydroxyvitamin D levels (Finland).

OBJECTIVES: The aim was to evaluate the association between serum vitamin D (25-hydroxyvitamin D) level and risk of prostate cancer. METHODS: The nested case-control study was based on a 13-year follow-up of about 19,000 middle-aged men who attended the first screening visit within the Helsinki Heart Study and were free of clinically verified prostate cancer at baseline. Through record linkage with the files of the Finnish Cancer Registry, 149 prostate cancer cases were identified in the cohort. They were matched (1:4) to probability density sampled controls for age, time of sample retrieval, and residence. Serum levels of 25-hydroxyvitamin D (25-VD) at entry were measured for cases and controls. The relative risks of prostate cancer were derived using conditional logistic regression analysis. RESULTS: Prostate cancer risk, analyzed by quartiles of the 25-VD levels, was inversely related to 25-VD. Men with 25-VD concentration below the median had an adjusted relative risk (OR) of 1.7 compared to men with 25-VD level above the median. The prostate cancer risk was highest among younger men (< 52 years) at entry and low serum 25-VD (OR 3.1 nonadjusted and 3.5 adjusted). Among those younger men (< 52 years), low 25-VD entailed a higher risk of non-localized cancers (OR 6.3). The mean age at diagnosis of the patients with 25-VD concentration above the median was 1.8 years higher than that of patients with vitamin D below the median (63.1 vs 61.3 years). CONCLUSIONS: We conclude that low levels of 25-VD associated with an increased risk for subsequent earlier exposure and more aggressive development of prostate cancer, especially before the andropause.

Adult↗
PubMed2000

Inhibin A, B and pro-alphaC in serum and peritoneal fluid in postmenopausal patients with ovarian tumors.

OBJECTIVE: To compare serum and peritoneal fluid concentrations of inhibin A, B, and pro-alphaC in women with ovarian tumors. METHODS: Serum and peritoneal fluid samples were taken from 41 postmenopausal women operated on for an ovarian tumor. Twenty-one patients with endometrial cancer formed a control group. Serum and peritoneal fluid inhibin A, B, and pro-alphaC concentrations, and serum FSH and tumor marker CA 125 (study group only) concentrations were analyzed. RESULTS: Inhibin A was found in low concentrations (median 4.1pg/ml, range <2-29pg/ml) in serum in most postmenopausal patients with epithelial ovarian carcinoma, whereas inhibin B was not measurable. Inhibin pro-alphaC circulated in high concentrations (median 125pg/ml, range 37->1000pg/ml). All inhibins were found in clearly greater concentrations in the peritoneal fluid than in serum. International Federation of Gynecology and Obstetrics (FIGO) stage III-IV and poor differentiation grade were associated with significantly lower concentrations of inhibin A and pro-alphaC in the peritoneal fluid compared with stages I-II or low grade. This correlation was not found in the serum concentrations of inhibin A or pro-alphaC. In the control group, no dimeric inhibins were found in serum, and pro-alphaC circulated in median concentrations of 47pg/ml (range 12-174pg/ml). CONCLUSIONS: Postmenopausal patients with epithelial ovarian tumors had low concentrations of inhibin A and relatively high concentrations of inhibin pro-alphaC in serum. The peritoneal fluid concentrations of all inhibins far exceeded those in the serum. Relatively low concentrations of inhibin A and pro-alphaC in the peritoneal fluid of patients with ovarian cancer seem to be associated with high stage and grade and, to a lesser degree, with positive peritoneal cytology.

Aged↗
PubMed1999

Only a small portion of the cytoplasmic progesterone receptor is associated with Hsp90 in vivo.

In cell extracts all of the nonliganded steroid receptor molecules are found as an oligomeric complex with Hsp90 and other proteins. In previous studies we have shown that Wild-type Hsp90 and progesterone receptor (PR) are located in different cell compartments (Tuohimaa et al. [1993] Proc. Natl. Acad. Sci. USA 90:5848-5852). In the present work we studied whether PR and Hsp90 can efficiently associate provided they are present in the same cell compartment. The association of Hsp90 with PR in vivo was studied by nuclear cotranslocation and immunohistochemistry with an antibody (alphaD) which can distinguish between the oligomeric and dissociated form. Upon expression of a cytoplasmic mutant of PR with Wild-type (cytoplasmic) Hsp90 and Wild-type (nuclear) PR with NLS-Hsp90 (a Hsp90 with a nuclear localization signal), we noted that the epitope of alphaD in PR was exposed in both cases. Also, in vivo crosslinking and treatment of cells with substances which stabilize the oligomeric complex in vitro were inefficient in demonstrating or inducing a similar oligomeric receptor form detectable in vitro in cell homogenates. However, when the cytoplasmic PR mutant (DeltaPR) was coexpressed with a nuclear form of Hsp90 (NLS-Hsp90), a portion of PR was cotranslocated into the nucleus. This would indicate that steroid receptors are indeed associated with Hsp90 in intact cells, but the Hsp90-associated receptor pool represents only a small portion of the receptors. This suggests that the majority of oligomeric complexes seen in cell extracts are formed during cell fractionation.

Animals↗
PubMed1999

Distribution of progesterone receptor in female mouse tissues.

Two novel antibodies against the mammalian progesterone receptor (PR) were raised and characterized to study the distribution of PR and the effect of estrogen on PR expression in various female murine tissues by immunohistochemistry. There were estrogen-independent constitutive PR expressions in the smooth muscle cells of uterus, uterine blood vessels, urinary bladder, duodenum, and jejunum of ovariectomized mice. Uterine stromal cells, capsular cells of kidney and adrenal gland, and the epithelial cells of submandibular gland expressed PR constitutively. PR expression was detected in some thymic cells and the number of PR-positive thymic cells increased markedly after estrogen treatment. Estrogen induced PR expression in the epithelial cells of uterus, vagina, urethra, and skin and the stromal cells of vagina, urethra, and pancreatic ducts, as well as the smooth muscle cells of some blood vessels. These results suggest cell-specific progesterone actions in the urinary tract, skin, and gastrointestinal organs, on the immune functions, and on the regulation of local blood flow.

Animals↗
PubMed1999

Prognostic factors in controlled ovarian hyperstimulation.

OBJECTIVE: To determine whether the number of retrieved oocytes and the required amount of gonadotropins per oocyte in IVF treatment can be predicted with use of the following independent predictive variables: age, parity, cause of infertility, body mass index, day 3-5 FSH, E2, inhibin B, ovarian volume, the number of follicles, and intraovarian and uterine artery vascular resistance measured by ultrasonography before ovarian hyperstimulation. DESIGN: A retrospective analysis. SETTING: University hospital infertility clinic. PATIENT(S): Seventy-four consecutive women attending the university hospital infertility clinic for IVF treatment. INTERVENTION(S): The investigated factors were measured on day 3-5 of the cycle, in which luteal phase suppression was begun before ovarian hyperstimulation preparatory to IVF. MAIN OUTCOME MEASURE(S): The amount of gonadotropins required per oocyte and the number of retrieved oocytes were correlated with the predictive factors in stepwise regression analysis. RESULT(S): The best predictive factors for the number of oocytes retrieved were FSH, inhibin B, and parity, explaining 25% of the ovarian response. Intraovarian vascular resistance, parity, FSH, and inhibin B best predicted the amount of gonadotropins needed, explaining 44% of the variation. CONCLUSION(S): FSH, inhibin B, and parity were the independent predictive factors for the number of retrieved oocytes. The same factors and intraovarian vascular resistance predicted the required amount of gonadotropins per oocyte. The main part of the ovarian response cannot be predicted using the factors investigated.

Adult↗
PubMed1999

Identification of a nuclear localization signal in activin/inhibin betaA subunit; intranuclear betaA in rat spermatogenic cells.

Activin is a dimeric glycoprotein hormone that was initially characterized by its ability to stimulate pituitary FSH secretion and was subsequently recognized as a growth factor with diverse biological functions in a large variety of tissues. In the testis, activin has been implicated in the auto/paracrine regulation of spermatogenesis through its cognate cell membrane receptors on Sertoli and germ cells. In this study we provide evidence for intranuclear activin/inhibin betaA subunit and show its distribution in the rat seminiferous epithelium. We have shown by transient expression in HeLa cells of beta-galactosidase fusion proteins that the betaA subunit precursor contains a functional nuclear localization signal within the lysine-rich sequence corresponding to amino acids 231-244. In all stages of the rat seminiferous epithelial cycle, an intense immunohistochemical staining of nuclear betaA was demonstrated in intermediate or type B spermatogonia or primary spermatocytes in their initial stages of the first meiotic prophase, as well as in pachytene spermatocytes and elongating spermatids primarily in stages IX-XII. In some pachytene spermatocytes, the pattern of betaA immunoreactivity was consistent with the characteristic distribution of pachytene chromosomes. In the nuclei of round spermatids, betaA immunoreactivity was less intense, and in late spermatids it was localized in the residual cytoplasm, suggesting disposal of betaA before spermatozoal maturation. Immunoblot analysis of a protein extract from isolated testicular nuclei revealed a nuclear betaA species with a molecular mass of approximately 24 kDa, which is more than 1.5 times that of the mature activin betaA subunit present in activin dimers. These results suggest that activin/inhibin betaA may elicit its biological functions through two parallel signal transduction pathways, one involving the dimeric molecule and cell surface receptors and the other an alternately processed betaA sequence acting directly within the nucleus. According to our immunohistochemical data, betaA may play a significant role in the regulation of nuclear functions during meiosis and spermiogenesis.

Activins↗
PubMed1998

Inhibin A and B in peri- and postmenopause.

OBJECTIVE: The aim of the study was to investigate the origin of inhibin A and B during the last years of the reproductive age and after menopause by measuring their levels in the ovarian and peripheral venous blood. METHODS: The study population consisted of 43 women, aged 42-69 years (mean 50), who underwent hysterectomy with ovarian removal for a benign disease. A total of 24 of them were in follicular phase, 11 in luteal phase, and eight were postmenopausal. Peripheral and ovarian venous blood was collected for measurement of inhibin A and B. In addition, sex steroid hormone and gonadotropin levels were measured. RESULTS: Ovarian venous inhibin B correlated significantly with ovarian estradiol secretion (r = 0.5, P = 0.001). The levels of inhibin B were significantly higher in the ovarian vein than in the peripheral vein (P = 0.006). The highest inhibin B concentrations were detected in the mid-proliferative (mid-follicular) phase (median 31.6 pg/ml range 25.9-47.9). In postmenopausal women, inhibin B was not detectable. No correlation between FSH and ovarian inhibin B was found. Inhibin A rose rapidly in late proliferative (late follicular) phase (median 28.5, range < 2-51.8) and dominated in the circulation throughout the luteal phase (median 20.9, range 8.8-60). For inhibin A, no concentration gradient existed between the ovarian and peripheral vein. Unlike inhibin B, inhibin A was detectable in ovarian and peripheral blood in postmenopausal women. A significant negative correlation between ovarian and peripheral inhibin A and FSH was found (r = -0.386, P = 0.015; r = -0.345, P = 0.034, respectively). CONCLUSION: Inhibin B correlates with ovarian estradiol secretion and seems to reflect follicular function. Inhibin A dominates in circulation during the luteal phase but is detectable at low concentrations both in follicular phase and even in postmenopause. Our findings suggest that inhibin A may play a role in FSH suppression in the female reproduction. In addition to the ovary, there may be extragondal source(s) of inhibin A.

Adult↗
PubMed1998

Hormonal and photoperiodic modulation of testicular mRNAs coding for inhibin/activin subunits and follistatin in Clethrionomys glareolus, Schreber.

Photoperiodic and hormonal modulation of mRNAs for testicular inhibin/activin subunits and follistatin were studied in a seasonally breeding rodent, the bank vole (Clethrionomys glareolus). Photoperiod-induced testicular regression had no effect on the relatively low steady-state levels of follistatin mRNA. Inhibin alpha (I alpha) and beta B (I beta B) mRNA levels were significantly higher in regressed than in active gonads, but inhibin beta A was undetectable. The effect of gonadotropin administration on testicular weight and mRNA concentrations differed between the sexually active and quiescent voles. Neither FSH (1.2 U/kg; s.c. for 5 days) nor hCG (600 IU/kg; s.c. for 5 days) affected testicular weight in sexually active voles, whereas both gonadotropins significantly increased testicular weight in photo-regressed individuals. FSH had no effect on I alpha or I beta B mRNA concentrations in the active testes, whereas excessive hCG challenge induced a decrease in the steady-state levels of these mRNAs. FSH induced an increase in I alpha mRNA concentrations in the regressed gonad, whereas both gonadotropins concomitantly down-regulated I beta B mRNA levels. In conclusion, the high expression of I alpha and I beta B mRNA in the regressed testis imply autocrine and paracrine roles for inhibin/activin in the quiescent gonad of seasonal breeders. Inhibin alpha-subunit expression is at least partly under the control of FSH in the bank vole testis.

Activins↗
PubMed1998

Progesterone receptor in chicken bursa of Fabricius and thymus: evidence for expression in B-lymphocytes.

In the present work constitutive progesterone receptor (PR) expression in the chicken bursa of Fabricius was detected in the stromal, smooth muscle and follicular medullary cells and smooth muscle cells of blood vessels. PR expression was increased during sexual maturation and after estrogen treatment. Bursal medullary PR-positive cells were further characterized to be B-lymphocytes by flow cytometric analysis. In addition, estrogen induced expression of PR in the bursal FAE-cells (follicle-associated epithelial cells). In the thymus PR was expressed constitutively in the connective tissue cells of the capsule and interfollicular septa, in a few medullary cells and in vascular smooth muscle. The PR-positive medullary cells consisted of epithelial cells, large polygonal cells resembling macrophages and plasma cells. T-lymphocytes were PR-negative. Estrogen up-regulated PR expression in the thymus. Immunoblotting studies revealed that both isoforms of PR, i.e. PR-A and PR-B, were expressed in the bursa of Fabricius and thymus with PR-B dominance. These results suggest that the chicken primary lymphoid organs bursa and thymus are under regulation of estrogen and progesterone. Expression of PR in B-lymphocytes, macrophages and plasma cells in the chicken is documented for the first time and suggests evidence for direct action of progesterone on immune responses.

Animals↗
PubMed1998

Evidence for enhanced ubiquitin-mediated proteolysis of the chicken progesterone receptor by progesterone.

Genomic actions of progesterone are mediated via A and B isoforms of the progesterone receptor (PR). One major factor controlling PR level is progesterone causing negative autoregulation (down-regulation) of the receptor protein. In this work we studied the mechanism whereby progesterone exerts its effects on PR level in the chicken oviduct. We found that progesterone does not markedly regulate PR mRNA expression. Furthermore, we demonstrate here for the first time that PR is a target for ubiquitylation and that the proportion of ubiquitylated PR is increased by progesterone treatment. Our data suggest that ligand-induced down-regulation of PR involves enhanced degradation of receptor protein by ubiquitin-proteasome system in vivo.

Amino Acid Sequence↗
PubMed1998

Localization of 1,25-dihydroxyvitamin D3 receptor (VDR) expression in human prostate.

1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has been found to have a variety of physiological functions, including effects on growth and differentiation in normal and malignant cells. The antiproliferative effects of 1,25(OH)2D3 are reported to be mediated through the genomic signaling pathway by binding to a specific high affinity receptor protein, the 1,25-dihydroxyvitamin D3 receptor (VDR). VDR has been localized in a variety of tissues, but little is known about VDR distribution in human prostate. In this study, we raised an antibody against a synthetic peptide corresponding to amino acids 10-24 of human vitamin D receptor. The sequence selected for immunization is identical in human, rat and mouse VDR. Based on this antibody, we developed an immunohistochemical method suitable for studying VDR expression in paraffin-embedded tissue. The immunohistochemical staining was verified using classical target organs for vitamin D (kidney, intestine, skin). With this method, we studied VDR localization on paraffin-embedded human prostatic tissue obtained from 8 patients undergoing radical prostatectomy for urinary bladder cancer and demonstrate VDR expression in the secretory epithelial and few stromal cells of human prostate. The nuclear staining in the secretory epithelial cells was concentrated near the nuclear membrane and in discrete foci in the nucleoplasm. This suggests that effects of 1,25-dihydroxyvitamin D3 are mediated through VDR in these cells. Moreover our result indicates that there are strong variations in VDR expression between prostatic samples.

Amino Acid Sequence↗
PubMed1998

Reappraisal of the role of heat shock proteins as regulators of steroid receptor activity.

Almost 30 years have passed since the original demonstration that steroid receptors, comprising a subfamily of the nuclear receptor (NR) superfamily, exist as large (6-8S) non-DNA-binding complexes in hypotonic extracts (cytosol) of target cells; later such complexes were shown to correspond to a heterooligomer composed of receptor, heat shock (Hsp), and other proteins. Subsequently, an impressive number of studies have dealt with the composition of the "nonactive" complex, its dissociation and/or reassembly in vitro, possible functions of the non-receptor components, and their subcellular compartmentalization. While there is little dispute about the chaperoning role of some Hsps in such a complex, there is still no final proof of an association in vivo of NRs and Hsps in the nuclei of target cells, which is requisite for a direct regulatory involvement of Hsps in NR function. Here we critically review the various models that have been put forward to attribute a biological function to the NR-Hsp90 interaction, evaluate the corresponding experimental data, and integrate recent concepts originating from the structural and functional analyses of NRs.

Animals↗
PubMed1998

Activin B: detection by an immunoenzymometric assay in human serum during ovarian stimulation and late pregnancy.

A recently developed immunoenzymometric assay for activin B has been characterized further by measurement during ovarian stimulation and pregnancy. The assay is based on a monoclonal anti-peptide antibody, anti-betaB(101-115). In addition to quantitative analyses, the antibody has been used for immunohistochemical localization of the activin betaB-subunit in human term placenta. Serum samples obtained from patients suffering from tubal factor infertility who were admitted for in-vitro fertilization (IVF) treatment protocols or from patients with proven fertility who were admitted for laparoscopic tubal ligation were collected. The aim was to correlate serum activin B concentrations with other parameters during IVF and with phases of the menstrual cycle. Serum samples obtained from healthy pregnant volunteers were studied to correlate activin B concentrations with clinical parameters. During the IVF treatment protocols, activin B was detectable in all patients studied, and a significant negative correlation was observed between serum activin B and oestradiol concentrations. On the other hand, no significant difference was observed in activin B concentrations when serum samples obtained from patients at different phases of the menstrual cycle were compared, and low concentrations of activin B were observed in the samples obtained from these patients. During pregnancy, a positive correlation was observed between serum activin B concentrations and gestational age. In immunohistochemical analyses of human placental tissue obtained from healthy parturients, the activin betaB-subunit was present in trophoblast, amniotic epithelial and Hofbauer cells. The results suggest a potential clinical application in female reproductive medicine for serum activin B measurements.

Activins↗
PubMed1997

Distribution of progesterone receptor in chicken: novel target organs for progesterone and estrogen action.

Expression of progesterone receptor (PR) in various organs of sexually immature chickens and after estrogen treatment was studied by immunohistochemical and Western blotting analyses. Constitutive PR expression was observed in the mesothelium and stroma of the esophagus, proventriculus, liver, spleen, pancreas, heart and lung. In the urogenital tract, PR was expressed in the mesothelial and stromal cells and smooth muscle of blood vessels. Estrogen treatment induced PR expression in the stroma and smooth muscle of the gall bladder and in the epithelium and stroma of the trachea. In the ovary of immature chickens PR was localized in the epithelium, stroma and smooth muscle and was induced in the granulosal cells by estrogen. In most tissues there was more PR-B than PR-A expression and this PR-B dominance remained after estrogen treatment. These results suggest that progesterone and estrogen may have physiological effects on many organs outside the genital tract not previously known as steroid-target tissues.

Animals↗