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Biomedical subjects

R Koistinen

Publications and source records attributed to R Koistinen.

At least 37 records · Page 2Linked to original sources
PubMed1998

Growth hormone induced increase in serum IGFBP-3 level is reversed by anabolic steroids in substance abusing power athletes.

OBJECTIVE: Body builders may use growth hormone (GH) and anabolic steroids to increase fitness and muscle mass. GH increases serum concentrations of IGF-I and IGFBP-3. The combined effects of GH and anabolic androgenic steroids on IGFBP-3 and IGF-I levels are not known under authentic substance-abusing conditions. The aim of this study was to investigate this in substance-abusing power athletes. DESIGN AND PATIENTS: Nine healthy, non-obese and non-competing male power athletes, all aggressive substance abusers, used GH and/or anabolic steroids independently of this study. Blood samples were taken both during and between the drug intake. Sixteen substance non-abusing wrestlers served as controls. MEASUREMENTS: Serum IGF-I concentration was measured by radioimmunoassay and the IGFBP-3 concentration was measured by two immunofluorometric assays, one detecting proteolytic fragments of IGFBP-3. The capacity of serum to proteolytically cleave IGFBP-3 was studied by the proteolysis assay. RESULTS: While growth hormone increased the IGFBP-3 and IGF-I concentrations, anabolic steroids decreased the same. Concomitant use of growth hormone and anabolic steroids decreased the IGFBP-3 concentration in five out of six abuse periods in spite of the fact that the IGF-I concentration remained elevated in four of them. However, in two men who were on low calorie diet both the IGF-I and IGFBP-3 concentrations decreased during combined GH/anabolic steroid abuse. No proteolytic fragmentation of IGFBP-3 was observed. CONCLUSION: Massive abuse of anabolic steroids decreases both the basal and GH-stimulated IGFBP-3 concentrations, whereas its effects on serum IGF-I concentration are variable and affected by low calorie diet. This study demonstrates that detection of GH doping by measuring the IGF-I and/or IGFBP-3 levels has notable confounding factors.

Adult↗
PubMed1998

Glycodelins: role in regulation of reproduction, potential for contraceptive development and diagnosis of male infertility.

Glycodelins are glycoproteins synthesized in various glands, with sequence homology to beta-lactoglobulins, and named according to their unique oligosaccharide structures. We purified, cloned and sequenced endometrium- and seminal plasma-derived glycodelins (GdA and GdS respectively) and found that they are involved in various types of cell-cell communications. These include interactions between the spermatozoon and the egg, and between immune cells and their targets. Endometrial GdA inhibits sperm-egg binding, whereas the differently glycosylated GdS in seminal plasma does not. These observation are of interest for reproductive physiology, detection of causes of infertility, and they also may have potential for contraceptive development.

Biomarkers↗
PubMed1997

Regulation of insulin-like growth factor-binding protein-1 and progesterone secretion from human granulosa-luteal cells: effects of octreotide and insulin.

OBJECTIVE: To examine the effects of the synthetic somatostatin-analogue octreotide and human recombinant insulin on the release of insulin-like growth factor binding protein-1 (IGFBP-1) and P from human granulosa-luteal cells. DESIGN: Primary culture of human granulosa-luteal cells. SETTING: Academic research laboratory. PATIENT(S): Women undergoing oocyte retrieval for IVF-ET because of tubal infertility. INTERVENTION(S): Octreotide or insulin were added to the cultures; sampling of culture medium was performed after 48 hours. MAIN OUTCOME MEASURE(S): Insulin-like growth factor binding protein-1 and P. RESULT(S): Octreotide significantly inhibited IGFBP-1 (58.8% compared with controls) and P release (66.1% compared with controls). Insulin abolished IGFBP-1 release while stimulating P release (200.7% compared with controls). There was a significant and positive correlation between IGFBP-1 and P levels. CONCLUSION(S): Octreotide and insulin have a significant effect on human granulosa-luteal cell function in terms of IGFBP-1 and P release. Our results suggest a local ovarian mechanism for the recently observed effects of octreotide in the treatment of women with polycystic ovary syndrome.

Cells, Cultured↗
PubMed1997

Levonorgestrel-releasing intrauterine device-wearing women express contraceptive glycodelin A in endometrium during midcycle: another contraceptive mechanism?

Intrauterine devices (IUDs) exert contraceptive action by interfering with sperm transport, ovum development, fertilization and implantation. Glycodelin A (GdA) is a uterine glycoprotein that has local contraceptive activity by inhibiting sperm-egg binding. GdA is normally absent from endometrium during the fertile midcycle and it is not expressed until the fifth postovulatory day. The phase of menstrual cycle addressed in this study covers the phase when conception is most likely to follow an unprotected intercourse and when GdA is normally absent. We present here evidence that levonorgestrel-releasing IUD (LNg-IUD) is accompanied by 'inappropriate' expression of GdA in endometrium between days 7 and 16 of the menstrual cycle (six out of six cases). The same was also found in copper-releasing IUD (Cu-IUD)-wearing women, but less frequently (four out of 11 cases, P < 0.0345, Fisher's exact test). In-situ hybridization localized GdA mRNA into endometrial glands in the midcycle endometrium, confirming the cellular site of synthesis. Based on the potent inhibitory activity of GdA on sperm-egg binding, the presence of GdA in uterine glands of IUD wearers may lead to prior exposure of sperm to contraceptive GdA, thus contributing to the contraceptive activity of the IUD.

Contraception↗
PubMed1997

Multiple forms of messenger ribonucleic acid encoding glycodelin in male genital tract.

Glycodelin-A is a human endometrium-derived glycoprotein with contraceptive and immunosuppressive activities. Recently, we found that seminal plasma contains immunoreactive glycodelin (GdS) that is differentially glycosylated and has no contraceptive activity. We now report localization and variant forms of GdS in the male genital tract. Northern blot and reverse transcription-PCR analyses showed that GdS mRNA is expressed in the seminal vesicles and ampulla of the vas deferens. Immunohistochemical staining localized GdS to the epithelial cells and lumen of glands in the seminal vesicles and ampullary part of the vas deferens. The same tissues and cells contained glycodelin mRNA as localized by in situ hybridization. Whereas the major reverse transcription-PCR products were identical to the glycodelin-A cDNA from decidual expression library, there were also several splicing variants of GdS mRNA. Seminal plasma also contained smaller immunoreactive forms of the GdS protein. Some of them were posttranslational cleavage products of GdS, because incubation of 125I-labeled GdS in seminal plasma resulted in smaller molecular weight cleavage products. Based on these results, we concluded that multiple forms of glycodelin mRNA are expressed in the male genital tract, including those lacking the coding sequences for the glycosylation sites, and that seminal plasma has proteolytic activity that cleaves GdS.

Aged↗
PubMed1997

Glycodelins GdA and GdS modified by 3-hydroxyphthalic anhydride inhibit gp120-CD4 binding and HIV-1 infection in vitro.

Bovine beta-lactoglobulin chemically modified with 3-hydroxyphthalic anhydride (3HP) was recently shown, at nanomolar concentrations, to block the binding site on CD4 for the HIV surface glycoprotein (gp120), potentially inhibiting HIV transmission. Human glycodelin has sequence homology with bovine beta-lactoglobulin and appears as different glycoforms in endometrium (GdA) and seminal plasma (GdS). We studied the anti-HIV effects of chemically modified GdA and GdS on both the infection of MT-2 cells by HIV-1IIIB, and the infection of peripheral blood mononuclear cells by the primary HIV isolate THA/93/051 belonging to subtype E. Whereas the native proteins were inactive when tested at physiologic concentrations, nanomolar concentrations of either 3HP-GdA or 3HP-GdS inhibited the production of HIV nucleocapsid p24, cytopathic effects of HIV-1IIIB, and infection of peripheral blood mononuclear cells by the primary HIV isolate THA/93/051. Moreover, both modified proteins inhibited gp120-CD4 binding, 3HP-GdS being more potent than 3HP-GdA (p = 0.0042). Because GdA and GdS have the same major protein core, the observed difference in gp120-CD4 binding must depend on the specific glycoform. In view of the previously reported contraceptive activity of GdA, the observed anti-HIV activity induced by its chemical modification should be of special interest in the development of antiviral strategies that may also have contraceptive effects.

Anti-HIV Agents↗
PubMed1996

Gender-specific glycosylation of human glycodelin affects its contraceptive activity.

We have recently demonstrated that a human amniotic fluid-derived glycoprotein, glycodelin-A (GdA; previously known as PP14 or PAEP), potently inhibits gamete binding in an established sperm-egg binding system and expresses immunosuppressive activities directed against a variety of different immune cell types. GdA has high mannose-, hybrid-, and complex-type biantennary oligosaccharides including structures with fucosylated or sialylated N, N'-diacetyllactosediamine (GalNAcbeta1-4GlcNAc) sequences, which are rare in other human glycoproteins. We now report the characterization of glycodelin-S (GdS). This is a human seminal plasma glycoprotein that is immunologically indistinguishable from GdA, but unlike the latter, does not inhibit human sperm-zona pellucida binding under hemizona assay conditions. Analysis of the N-glycans of GdS by mass spectrometry revealed that all glycoforms of GdS are different from those of GdA. GdS glycans are unusually fucose-rich, and the major complex-type structures are biantennary glycans with Lewisx (Galbeta1-4(Fucalpha1-3)GlcNAc) and Lewisy (Fucalpha1-2Galbeta1-4(Fucalpha1-3)GlcNAc) antennae. It is probable that these highly fucosylated epitopes contribute to the immunosuppressive activity of human seminal plasma and to the low immunogenicity of sperm. This study provides the first evidence for gender-specific glycosylation that may serve to regulate key processes involved in human reproduction.

Contraceptive Agents↗
PubMed1996

Genetic and environmental components of interindividual variation in circulating levels of IGF-I, IGF-II, IGFBP-1, and IGFBP-3.

We assessed the magnitude of the genetic component in the variation of circulating levels of insulin-like growth factors I and II (IGF-I and IGF-II), and their binding proteins IGFBP-1 and IGFBP-3 by measuring their serum concentrations in 32 monozygotic and 47 dizygotic adult twin pairs of the same sex. The intrapair correlation for the IGF-I levels was r = 0.41 (P < 0.009) for monozygotic twins and r = 0.12 (P < 0.22) for dizygotic twins. For the IGF-II concentration the intrapair correlations were r = 0.66 (P < 0.0001) for the monozygotic and r = 0.34 (P < 0.01) for the dizygotic twins. No significant intrapair correlation was found for IGFBP-1 levels in either group. The correlations for IGFBP-3 concentration were r = 0.65 (P < 0.0001) and r = 0.23 (P < 0.06) for monozygotic and dizygotic twins, respectively. Women had higher IGF-II levels than men (635+/-175 vs. 522+/-144 microg/liter; P < 0.0001) and IGFBP-3 levels were also higher in women compared with men (5441+/-1018 vs. 4496+/-1084 microg/liter; P < 0.001). The proportion of variance attributable to genetic effects was 38% for the IGF-I concentration, 66% for the IGF-II concentration, and 60% for the IGFBP-3 concentration. No significant heritability was found for the IGFBP-1 concentrations. Our results show that, in adults, there is a substantial genetic contribution responsible for interindividual variation of the circulating levels of IGF-I, IGF-II, and IGFBP-3, but not for the IGFBP-1 levels.

Adult↗
PubMed1996

Hemoglobin level is linked to growth hormone-dependent proteins in short children.

Erythropoiesis was investigated in 32 children wih short stature and in eight children with skeletal dysplasia by studying blood hemoglobin in relation to growth and to serum concentrations of insulin-like growth factor I (IGF-I), IGF binding protein-3 (IGFBP-3), and erythropoietin (EPO) before, during, and after 12 months of recombinant human growth hormone (GH) treatment. Blood hemoglobin concentration was positively correlated with relative body height and with serum IGF-I and IGFBP-3 levels (P = .001 to .02), but not with the concentrations of EPO. The normal age-dependency of hemoglobin was lacking. Hemoglobin levels and their responses to GH treatment were similar in the patients with GH deficiency and those with normal GH secretion. Treatment with GH accelerated growth and elevated the concentrations of hemoglobin, IGF-I, and IGFBP-3. In the eight patients with skeletal dysplasia, body mass increased similarly, but gain in height was less than in the other patients, and the increase in hemoglobin was markedly pronounced. In this group, the correlations between hemoglobin, IGF-I, and IGFBP-3 were extremely close (r = 0.80 to 0.85, P = .031 to .008). These findings are in accord with earlier observations from in vitro and animal studies, and suggest that the GH-IGF axis is involved in the physiologic elevation of hemoglobin levels during childhood.

Achondroplasia↗
PubMed1996

Double-blind placebo controlled study: human biosynthetic growth hormone for assisted reproductive technology.

OBJECTIVE: To study whether the effect of cotreatment with human biosynthetic GH improves the outcome of poor IVF responders. DESIGN: A double-blind placebo-controlled study using a GnRH agonist (GnRH-a) and gonadotropin in a "boost" flare-up protocol for ovarian stimulation together with either placebo, 4, or 12 IU of human GH followed by oocyte retrieval and IVF-ET. PATIENTS: Twenty-two patients with previously demonstrated poor responses in at least two assisted reproductive technology cycles were recruited. INTERVENTIONS: Pretreatment and post-treatment blood samples and daily morning blood samples during ovarian stimulation were collected after an overnight fast. Human GH or placebo and GnRH-a were administered SC; gonadotropin was administered IM. Oocytes were collected by ultrasound-guided transvaginal aspiration of follicles. Embryos were cultured in vitro and transferred transcervically. MAIN OUTCOME MEASURES: Serum E2, FSH, GH, insulin-like growth factor-I (IGF-1), IGF binding protein 1 (IGFBP-1), and IGFBP-3 concentrations. Number of FSH ampules, follicles, oocytes, embryos, and pregnancies. RESULTS: No improvement in cycle outcome was demonstrated with daily adjuvant human GH administration with either 4 or 12 IU. Serum IGF-I levels were highest in the 12 IU human GH group and lowest in the placebo group. Serum IGFBP-3 levels increased 2 days after IGF-I levels in the 12 IU human GH group only. Serum IGFBP-1 levels were unchanged in all groups. CONCLUSION: Poor IVF responders do not benefit from cotreatment with human GH during their ovarian stimulation.

Adult↗
PubMed1996

A role for glycoconjugates in human development: the human feto-embryonic defence system hypothesis.

The mechanisms underlying the protection of the human embryo/fetus from the maternal immune response are poorly understood. Substantial evidence indicates that carbohydrate recognition plays a primary role in the sequestration of leukocytes during inflammatory processes, lymphocyte homing, and initial gamete binding. Our previous studies suggest a possible convergence in the types of carbohydrate sequences recognized during initial human gamete binding and immune/inflammatory cell interactions. Our more recent findings indicate that oligosaccharides participating in such processes are also associated with soluble glycoconjugates found in the human placenta, amniotic fluid, and decidua. We theorize that such glycoconjugates may abrogate the maternal immune/inflammatory response by blocking the primary adhesive interactions required for the expression of such activities. Foreign embryonic cells may also be protected by surface expression of oligosaccharide sequences that suppress immune effector cell action in a manner not dependent upon classical major histocompatibility (MHC) recognition. Glycoconjugates expressing selectin ligands may also manifest a potent contraceptive effect that may also be beneficial for both the mother and the developing embryo/fetus. This hypothesis provides a preliminary framework for understanding how temporally and spatially restricted immunosuppressive effects could be expressed in utero that protect the human embryo/fetus during this period of human development.

Animals↗
PubMed1996

Glycodelin from seminal plasma is a differentially glycosylated form of contraceptive glycodelin-A.

Glycodelin-A is a human amniotic fluid-derived glycoprotein with contraceptive and immunosuppressive activities. An immunoreactive form of glycodelin was detected in seminal plasma over a decade ago, but definitive characterization of this glycoprotein was not pursued. We considered it unlikely that the seminal plasma of fertile men would contain an appreciable amount of contraceptive glycodelin-A. To address this issue we purified seminal plasma glycodelin (glycodelin-S) and performed comparative studies with glycodelin-A. Glycodelin-S behaved differently when compared with glycodelin-A during sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing but identically after enzymatic deglycosylation. N-terminal sequencing of glycodelin-A and glycodelin-S gave identical results, and digestion with trypsin gave identical peptide fragments. The glycoproteins were also found to be indistinguishable from each other based upon immunological analyses. These results indicate that glycodelin-S and glycodelin-A have similar overall protein structure, suggesting the likelihood that these glycoproteins are differentially glycosylated forms of very similar proteins. This latter possibility is supported by lectin binding studies indicating that, unlike glycodelin-A, glycodelin-S does not manifest any affinity for lectins from Wisteria floribunda or Sambucus nigra. The results of sugar analysis and neuraminidase digestion also lead us to conclude that glycodelin-S and glycodelin-A are differentially glycosylated forms of similar proteins. Our evidence indicates that glycodelin-A mediated its biological activities via its unusual oligosaccharide sequences that are not associated with glycodelin-S. In lectin-immunoassay no appreciable amount of contraceptive glycodelin-A was found in the 22 seminal plasma samples studied.

Amidohydrolases↗
PubMed1996

Effect of marathon run on serum IGF-I and IGF-binding protein 1 and 3 levels.

Acute physical exercise increases growth hormone (GH) secretion, and GH regulates the expression of insulin-like growth factor I (IGF-I) and IGF-binding protein (IGFBP) 3. IGFBP-1 is a local modulator of IGF activity with rapid dynamic regulation that is downregulated by insulin. The IGF system mediates the metabolic actions of GH, and possibly it regulates glucose metabolism. We hypothesize that strenuous exercise causes changes in the IGF system. We studied the effects of the marathon run on the circulating levels of IGF-I, IGFBP-1, IGFBP-3, and insulin in 23 participants. Immediately after the run, the most striking change was an 11.6-fold median increase in serum IGFBP-1 level (from 63.7 +/- 50.5 to 736 +/- 408 micrograms/l; P < 0.001). Because the insulin level remained unchanged, the elevation of serum IGFBP-1 level cannot be explained by changes in insulin. One day after the run, the IGFBP-1 level had returned to baseline. The physiological role of this increment could be the inhibition of hypoglycemic effects of IGF-I and/or regulation of glucose availability to the muscles. The changes in IGF-I and IGFBP-3 levels were less dramatic: the IGF-I and IGFBP-3 levels were lower 1 and 3 days after the run. This report provides an important basis for authentic effects of strenuous exercise on the IGF-system.

Adult↗
PubMed1996

Recombinant human growth hormone improves growth in children receiving glucocorticoid treatment after liver transplantation.

Linear growth is often impaired after successful liver transplantation. The cause is multifactorial; poor graft function and long term glucocorticoid treatment are the main factors responsible. The efficacy and safety of recombinant human GH (rhGH) treatment were assessed in eight growth-retarded children (five boys and three girls) with liver transplants. Immunosuppression comprised azathioprine, cyclosporin, and methylprednisolone. rhGH was administered in a dose of 1 IU/kg x week, given by daily sc injections. The median age at the start of treatment was 9.7 yr (range, 5.9-14.9 yr). All but one of the patients remained prepubertal during treatment. The median growth rate increased from 3.2 to 7.l cm/yr (P = 0.025) and height SD score increased from -3.9 to -3.1 (P = 0.036) during the first year of rhGH treatment. Serum insulin-like growth factor I and insulin-like growth factor-binding protein-3 levels increased significantly during treatment. Graft function was normal in all except one patient, and no rejections or other serious side-effects were documented. In conclusion, rhGH treatment is effective in short, non-GH-deficient, liver-transplanted children receiving long term glucocorticoid treatment. Due to potential risk of allograft rejection, close monitoring of liver function and immunosuppression is required.

Azathioprine↗
PubMed1996

Normal human ovary and ovarian tumors express glycodelin, a glycoprotein with immunosuppressive and contraceptive properties.

Glycodelin is a glycoprotein with potent immunosuppressive and contraceptive activities. It reacts with antibodies against placental protein 14, or progesterone-associated endometrial protein, and has a unique carbohydrate structure. Previous nomenclature is misleading, because glycodelin is neither synthesized in the placenta nor is it endometrium specific. No ovarian synthesis of glycodelin has been demonstrated. We present evidence for glycodelin synthesis in the human ovary and ovarian tumors. In follicular phase, immunoperoxidase staining of microwave-treated tissue sections employing affinity-purified polyclonal antibodies localized glycodelin to areas of stromal cell condensation in ovarian cortex, theca interna, and the granulosa. 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. In situ hybridization gave negative results for glycodelin mRNA in normal ovary, whereas in ovarian tumors strong expression of both the glycodelin mRNA and the protein were found in benign and malignant serous cystadenomas, mucinous ovarian tumors being negative. We conclude that glycodelin is synthesized in human ovarian tumors, and its occurrence in normal human ovary may represent either synthesis or a site of glycodelin action.

Adult↗
PubMed1995

Differences in linear growth and cortisol production between liver and renal transplant recipients on similar immunosuppression.

Linear growth is more often impaired after liver than after renal transplantation (Tx) in childhood. As similar triple immunosuppression was used in our liver and renal transplant recipients, we were able to compare growth and endocrine function between 19 prepubertal liver and 35 renal transplant recipients. There were no significant differences in median age, weight-for-height index, or height standard deviation score at Tx. Seventy-eight percent of the liver Tx patients, but only 7% of the renal Tx patients, were below the normal range for height 3 years after Tx. Graft function was good in both liver and renal transplant recipients 3 years after Tx. There was no significant difference in growth hormone secretion, serum insulin-like growth factor (IGF)-I, and IGF-binding protein-3 levels, or in methylprednisolone and cyclosporine doses. However, the blood cyclosporine levels were significantly higher in the liver transplant recipients (P = 0.001 1 year and P = 0.005 2 years after Tx). Cortisol production was significantly lower in the liver transplant recipients (P = 0.002 1 year and P = 0.049 2 years after Tx), which suggests greater steroid-mediated suppression of adrenal function. Growth inhibition is more often observed in liver than in renal transplant recipients on similar triple immunosuppression, and may not be related to deficient function of the growth hormone-IGF-I axis. Similar cyclosporine doses result in higher plasma levels of the drug and similar methylprednisolone doses result in more inhibited adrenal cortisol production in liver transplant recipients. In children with organ transplants, cyclosporine and methylprednisolone should be administered on an individual basis.

Adrenocorticotropic Hormone↗