Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide with a w... more Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide with a widespread distribution both in the nervous system and peripheral organs. The peptide is also present in the female gonadal system, indicating its role in reproductive functions. While a lot of data are known on PACAP-induced effects in oogenesis and in the regulation of gonadotropin secretion at pituitary level, its placental effects are somewhat neglected in spite of the documented implantation defi cit in mice lacking endogenous PACAP. The aim of the present review is to give a brief summary on the occurrence and actions of PACAP and its receptors in the placenta. Radioimmunoassay (RIA) measurements revealed increased serum PACAP levels during the third trimester and several changes in placental PACAP content in obstetrical pathological conditions, further supporting the function of PACAP during pregnancy. Both the peptide and its receptors have been shown in different parts of the placenta and the umbilical cord. PACAP infl uences blood vessel and smooth muscle contractility of the uteroplacental unit and is involved in regulation of local hormone secretion. The effects of PACAP on trophoblast cells have been mainly studied in vitro. Effects of PACAP on cell survival, angiogenesis and invasion/ proliferation have been described in different trophoblast cell lines. PACAP increases proliferation and decreases invasion in proliferative extravillous trophoblast cells, but not in primary trophoblast cells, where PACAP decreased the
Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide having a... more Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide having a widespread distribution both in the nervous system and peripheral organs including the female reproductive system. Both the peptide and its receptors have been shown in the placenta but its role in placental growth, especially its human aspects, remains unknown. The aim of the present study was to investigate the effects of PACAP on invasion, proliferation, cell survival, and angiogenesis of trophoblast cells. Furthermore, cytokine production was investigated in human decidual and peripheral blood mononuclear cells. For in vitro studies, human invasive proliferative extravillous cytotrophoblast (HIPEC) cells and HTR-8/SVneo human trophoblast cells were used. Both cell types were used for testing the effects of PACAP on invasion and cell survival in order to investigate whether the effects of PACAP in trophoblasts depend on the examined cell type. Invasion was studied by standardized inv...
Oxidative stress plays an important role in various renal and hepatic pathologies, and reduction ... more Oxidative stress plays an important role in various renal and hepatic pathologies, and reduction of oxidative stress-induced processes is an important protective strategy in tissues of diverse origins against harmful stimuli. Pituitary adenylate cyclase activating polypeptide (PACAP) is a well-known cytotrophic and cytoprotective peptide. PACAP promotes cell survival in numerous cells and tissues exposed to various stimuli. Protective effects of PACAP have been shown in the kidney, but it is not known whether PACAP is protective against oxidative stress in renal cells. Little is known about the effects of PACAP in the liver. The aim of the present study was to investigate whether PACAP is protective against oxidative stress in primary rat kidney cell culture and whether PACAP has any effect on cell survival in human WRL-68 hepatocytes and HEP-G2 hepatocellular carcinoma cells subjected to oxidative stress. Cells were exposed to various concentrations of H(2)O(2) with or without PACAP co-treatment and cell viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test (MTT). We found that oxidative stress induced a significant decrease in cell viability in both cell lines. PACAP could dose-dependently increase the percentage of living cells in kidney cells, but it failed to do so in hepatocytes. Given the survival-promoting effects of PACAP against oxidative stress in rat kidney, we conducted a further experiment to determine whether PACAP influences the markers of oxidative stress in vivo. We have proven earlier that PACAP was effective in kidney ischemia/reperfusion injury in vivo. In the present study, we determined the levels of the oxidative stress marker malondialdehyde and the activity of the scavenger molecules glutathione (GSH) and superoxide dismutase (SOD) following kidney ischemia/reperfusion in rats. We found that PACAP significantly increased the level of GSH and counteracted the marked reduction of SOD activity after ischemia/reperfusion in vivo. In summary, the present study showed that while PACAP was able to significantly increase the cell survival in primary kidney cell cultures exposed to oxidative stress, possibly involving interaction with the endogenous scavenger system, it failed to influence the viability of normal or cancerous hepatocytes.
The effects of pituitary adenylate cyclase activating polypeptide (PACAP) are mediated through G-... more The effects of pituitary adenylate cyclase activating polypeptide (PACAP) are mediated through G-protein-coupled receptors, the specific PAC1 receptor and VPAC1 and VPAC2 receptors which bind vasoactive intestinal peptide with similar affinity. Based on binding affinity studies, PACAP6-38 was discovered as a potent antagonist of PAC1 and it has been used by hundreds of studies as a PACAP antagonist. Recently, we have found that in certain cells/tissues, PACAP6-38 does not antagonize PACAP-induced effects, but surprisingly, it exerts similar actions to PACAP1-38, behaving as an agonist. In the present study, we report on the agonistic behavior of PACAP6-38 on neuropeptide release from sensory nerves of the isolated rat trachea and on the MAPK signaling pathways in cytotrophoblast cells. In isolated rat tracheae, PACAP6-38, similarly to PACAP1-38, induced significant inhibitory effects on the release of three simultaneously measured sensory neuropeptides, substance P, calcitonin gene-related peptide, and somatostatin evoked by both chemical excitation and electrical field stimulation of capsaicin-sensitive afferents. Effects of PACAP6-38 were the same as those of PACAP1-38 on MAPK signaling in human cytotrophoblast cells. Western blot analysis showed that both peptide forms stimulated ERK1/2 and JNK phosphorylation, while they both inhibited p38 MAPK phosphorylation. The most pronounced effects were observed when both peptides were present. In summary, our results show that PACAP6-38, which is a PACAP receptor antagonist in most cells/tissues, can behave as an agonist in other systems. The increasing interest in the effects of PACAP requires further studies on the pharmacological properties of the peptide and its analogues.
Objective: To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laborat... more Objective: To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laboratory diagnosis of endometriosis and various gynecologic disorders. Design: Prospective case-control study. Setting: University medical centers. Patient(s): A total of 135 women of reproductive age were involved in the study, 77 endometriosis patients, 28 gynecologic controls, and 30 healthy women. Intervention(s): Diagnostic laparoscopy and collection of tissue biopsies, peritoneal cells, and native peripheral blood from different case groups of gynecology patients and healthy women. Main Outcome Measure(s): The expression of mRNA and serum concentration of Gal-9. Result(s): Semiquantitative reverse transcription-polymerase chain reaction analysis and serum soluble Gal-9 ELISA were performed on three different cohorts of patients: those with endometriosis, those with benign gynecologic disorders, and healthy controls. Differences in the Gal-9 concentrations between the investigated groups and the stability of Gal-9 in the serum and diagnostic characteristics of Gal-9 ELISA were determined by statistical evaluation and receiver operating characteristic (ROC) curve analysis. Significantly elevated Gal-9 levels were found in both minimal-mild (I-II) and moderate-severe (III-IV) stages of endometriosis in comparison with healthy controls. At a cutoff of 132 pg/mL, ROC analysis revealed an excellent diagnostic value of Gal-9 ELISA in endometriosis (area under the curve ¼ 0.973) with a sensitivity of 94% and specificity of 93.75%, indicating better diagnostic potential than that of other endometriosis biomarkers. Furthermore, various pelvic pain or infertility-associated benign gynecologic conditions were also associated with increased serum Gal-9 levels. Conclusion(s): Our results suggest that Gal-9 could be a promising noninvasive biomarker of endometriosis and a predictor of various infertility or pelvic pain-related gynecologic disorders.
Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with survival-promotin... more Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with survival-promoting actions, has been observed in endocrine organs and is thought to play a role in reproductive functions, including pregnancy. PACAP occurs in two forms, 27 and 38 amino acid residues, with PACAP38 being the predominant form in human tissues. In the present study, we determined the concentrations of PACAP38 and PACAP27 in first-trimester and full-term human placentas using radioimmunoassay. We found high levels of PACAP38 and lower levels of PACAP27 in different parts of the full-term human placenta. PACAP38 content increased in the placenta during pregnancy, both on the maternal side and on the fetal side. The effects of PACAP on the survival of JAR human choriocarcinoma cells were investigated using flow cytometry and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell viability assay in cells exposed to the widely used chemotherapeutic agent methotrexate (MTX). It was found that PACAP neither influenced the survival of JAR cytotrophoblast cells nor affected cellular response to the death-inducing effect of the chemotherapeutic agent MTX. The present observations further support the significance of PACAP in the human placenta. The observation that PACAP did not influence the effects of MTX may have future clinical importance, showing that PACAP does not decrease the effects of certain chemotherapeutic agents.
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a widespread neuropeptide with a di... more Pituitary adenylate cyclase-activating polypeptide (PACAP) is a widespread neuropeptide with a diverse array of biological functions. Not surprisingly, the lack of endogenous PACAP therefore results in a variety of abnormalities. One of the important effects of PACAP is its neuroprotective and general cytoprotective role. PACAP protects neurons and other tissues against ischemic, toxic, and traumatic lesions. Data obtained from PACAP-deficient mice provide evidence that endogenous PACAP also has protective functions. Mice lacking PACAP are more vulnerable to different in vitro and in vivo insults. The present review summarizes data on the increased sensitivity of PACAP-deficient mice against harmful stimuli. Mice lacking PACAP respond with a higher degree of injury in cerebral ischemia, autoimmune encephalomyelitis, and axonal lesion. Retinal ischemic and excitotoxic injuries also produce increased cell loss in PACAP-deficient mice. In peripheral organs, kidney cell cultures from PACAP-deficient mice are more sensitive to oxidative stress and in vitro hypoxia.
Follicular growth, ovulation, and luteinization are influenced by interactions of peptide and ste... more Follicular growth, ovulation, and luteinization are influenced by interactions of peptide and steroid hormone-signaling cascades in the ovary. Pituitary adenylate cyclase-activating polypeptide (PACAP) plays an important role in the regulation of several endocrine processes and is present in ovarian follicular fluid (FF). However, little is known about PACAP in FF with regard to maturation, ovulation, fertilization, and successful pregnancy. The aim of this pilot study was to investigate whether there is a correlation between PACAP concentration in FF and ovarian response to superovulation treatment in infertile women, performed in volunteers (n = 132; aged between 20 and 35). After treatment, the number of harvested oocytes was recorded and PACAP immunoreactivity in FF was measured by radioimmunoassay. All the corresponding PACAP concentrations were below 290 fmol/ml in cases when the number of harvested oocytes exceeded 14 per patient, while in all cases above 290 fmol/ml, the number of oocytes was below 14. Using these cutoff values, we determined three study groups: high-PACAP concentration, high-oocyte number, and low-PACAP concentration-low-oocyte number groups. Median values of PACAP concentration in these groups were 411.2, 106.5, and 101.0 fmol/ml, respectively, while the median values of harvested oocytes were 5.5, 19.0, and 5.0, respectively. Differences were significant, indicating a correlation between concentration of PACAP in FF and the number of recruited oocytes. Higher concentrations of PACAP in FF might be associated with lower number of developing oocytes, while low concentrations of PACAP might correlate with a markedly higher number of ova retrieved, thus predicting a higher chance for ovarian hyperstimulation. Our present study is among the first few human clinical studies with direct conclusions drawn for possible clinical impact of PACAP.
Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with well-known cyto... more Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with well-known cytoprotective effects. We have reported earlier that PACAP decreases mortality and the degree of tubular atrophy in a rat model of renal ischemia/reperfusion injury. Recently, we have shown that kidney cultures isolated from PACAP deficient mice show increased susceptibility to renal oxidative stress. Based on these previous studies, we raised the question whether PACAP deficient mice display increased sensitivity to in vivo kidney ischemia/reperfusion. PACAP À/À mice underwent 45 or 60 min of renal ischemia followed by 2 weeks reperfusion. Kidneys were processed for histological analysis. Sections stained with PAS-haematoxylin were graded for the following parameters: degree of tubular dilation, Bowmann's capsule dilation, lymphocyte and macrophage infiltration, thyroidization and the disappearance of the PAS-positive glycocalyx from under the brush border. In other sets of experiments, tissue cytokine expression and the level of the endogenous antioxidant superoxide dismutase (SOD) were also determined after 60 min ischemia/reperfusion. Our results show that while intact kidneys were not different between wild-type and PACAP deficient mice, marked differences were observed in the histological structures in groups that underwent ischemia/reperfusion. PACAP deficient mice had a worse histological outcome, with significantly higher histological scores for all tested parameters. Cytokine expression was also markedly different between wild-type and PACAP deficient mice. In addition, the level of SOD was significantly lower in PACAP À/À animals after ischemia/reperfusion. In conclusion, the lack of endogenous PACAP leads to higher susceptibility to in vivo renal ischemia/reperfusion, suggesting that PACAP has an endogenous renoprotective effect.
Pituitary adenylate cyclase activating polypeptide (PACAP), a multifunctional neuropeptide, has 2... more Pituitary adenylate cyclase activating polypeptide (PACAP), a multifunctional neuropeptide, has 2 active forms, PACAP38 and PACAP27. It is now well-established that PACAP has several actions also in peripheral organs, including renoprotective effects. The peptide itself has not been previously identified in the rat kidney. The first aim of our study was to identify PACAP in the rat kidney using mass spectrometry and radioimmunoassay (RIA).
Although vasoactive intestinal polypeptide (VIP) is thought to be a prolactin releasing factor, i... more Although vasoactive intestinal polypeptide (VIP) is thought to be a prolactin releasing factor, in vivo studies on sheep suggest that it is inactive in this species. Recent studies, based primarily on the rat, suggest that the related pituitary adenylate cyclase-activating polypeptide (PACAP) is also a hypophysiotrophic factor but again in sheep, this peptide has no in vivo effects on hormone secretion despite being a potent activator of adenylate cyclase in vitro. This lack of response to either peptide in vivo in sheep could be due to the low concentration of peptide that reaches the pituitary gland following peripheral injection. In the present study we therefore adopted an alternative approach of evaluating in vitro effects of these peptides on GH, FSH, LH or prolactin secretion from dispersed sheep pituitary cells. In a time-course study, PACAP (1 mmol/l) increased GH concentrations in the culture medium between 1 and 4 h and again at 12 h but had no effect in the 6 and 24 h incubations. Prolactin, LH and FSH were not affected by PACAP. The response to various concentrations of PACAP (1 nmol/l-1 mmol/l) were then evaluated using a 3 h incubation. Again prolactin and LH were not affected by PACAP and there was a small increase in GH concentrations but only at high concentrations of PACAP (0.1 and 1 mmol/l; P<0.05). PACAP also stimulated FSH secretion in cells from some animals although this effect was small. The GH response to PACAP was inhibited by PACAP(6-38), a putative PACAP antagonist, but not by (N-Ac-Tyr1, D-Arg2)-GHRH(1-29)-NH 2, a GH-releasing hormone (GHRH) antagonist. The cAMP antagonist Rp-cAMPS was unable to block the GH response to PACAP suggesting that cAMP does not mediate the secretory response to this peptide. At incubation times from 1-24 h, VIP (1 mmol/l) had no effects on prolactin, LH or GH secretion and, in a further experiment based on a 3 h incubation, concentrations of VIP from 1 nmol/l-1 mmol/l were again without effect on prolactin concentrations. Interactions between PACAP and gonadotrophin releasing hormone (GnRH), GHRH and dopamine were also investigated. PACAP (1 nmol/l-1 mmol/l) did not affect the gonadotrophin or prolactin responses to GnRH or dopamine respectively. However, at a high concentration (1 mmol/l), PACAP inhibited the GH response to GHRH. In summary, these results show that PACAP causes a modest increase in FSH and GH secretion from sheep pituitary cells but only at concentrations of PACAP that are unlikely to be in the physiological range. The present study confirms that VIP is not a prolactin releasing factor in sheep.
Epidemiológiai vizsgálat a húgyuti fejlődési rendellenességek (renalis a/dysgenesis, polí/ multic... more Epidemiológiai vizsgálat a húgyuti fejlődési rendellenességek (renalis a/dysgenesis, polí/ multicystáscystás vesedysplasia, obstruktiv húgyuti rendellenességek és exstrophias húgyhólyag/cloaca) kórokainak feltárása érdekében, a Magyarországi Veleszületett Rendellenességek Eset-Kontroll Felügyelet (Hungarian Case-Control Surveillance of Congenital Abnormlalities) anyagában. A vizsgálat fő céljai:
Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide with a w... more Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide with a widespread distribution both in the nervous system and peripheral organs. The peptide is also present in the female gonadal system, indicating its role in reproductive functions. While a lot of data are known on PACAP-induced effects in oogenesis and in the regulation of gonadotropin secretion at pituitary level, its placental effects are somewhat neglected in spite of the documented implantation defi cit in mice lacking endogenous PACAP. The aim of the present review is to give a brief summary on the occurrence and actions of PACAP and its receptors in the placenta. Radioimmunoassay (RIA) measurements revealed increased serum PACAP levels during the third trimester and several changes in placental PACAP content in obstetrical pathological conditions, further supporting the function of PACAP during pregnancy. Both the peptide and its receptors have been shown in different parts of the placenta and the umbilical cord. PACAP infl uences blood vessel and smooth muscle contractility of the uteroplacental unit and is involved in regulation of local hormone secretion. The effects of PACAP on trophoblast cells have been mainly studied in vitro. Effects of PACAP on cell survival, angiogenesis and invasion/ proliferation have been described in different trophoblast cell lines. PACAP increases proliferation and decreases invasion in proliferative extravillous trophoblast cells, but not in primary trophoblast cells, where PACAP decreased the
Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide having a... more Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide having a widespread distribution both in the nervous system and peripheral organs including the female reproductive system. Both the peptide and its receptors have been shown in the placenta but its role in placental growth, especially its human aspects, remains unknown. The aim of the present study was to investigate the effects of PACAP on invasion, proliferation, cell survival, and angiogenesis of trophoblast cells. Furthermore, cytokine production was investigated in human decidual and peripheral blood mononuclear cells. For in vitro studies, human invasive proliferative extravillous cytotrophoblast (HIPEC) cells and HTR-8/SVneo human trophoblast cells were used. Both cell types were used for testing the effects of PACAP on invasion and cell survival in order to investigate whether the effects of PACAP in trophoblasts depend on the examined cell type. Invasion was studied by standardized inv...
Oxidative stress plays an important role in various renal and hepatic pathologies, and reduction ... more Oxidative stress plays an important role in various renal and hepatic pathologies, and reduction of oxidative stress-induced processes is an important protective strategy in tissues of diverse origins against harmful stimuli. Pituitary adenylate cyclase activating polypeptide (PACAP) is a well-known cytotrophic and cytoprotective peptide. PACAP promotes cell survival in numerous cells and tissues exposed to various stimuli. Protective effects of PACAP have been shown in the kidney, but it is not known whether PACAP is protective against oxidative stress in renal cells. Little is known about the effects of PACAP in the liver. The aim of the present study was to investigate whether PACAP is protective against oxidative stress in primary rat kidney cell culture and whether PACAP has any effect on cell survival in human WRL-68 hepatocytes and HEP-G2 hepatocellular carcinoma cells subjected to oxidative stress. Cells were exposed to various concentrations of H(2)O(2) with or without PACAP co-treatment and cell viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test (MTT). We found that oxidative stress induced a significant decrease in cell viability in both cell lines. PACAP could dose-dependently increase the percentage of living cells in kidney cells, but it failed to do so in hepatocytes. Given the survival-promoting effects of PACAP against oxidative stress in rat kidney, we conducted a further experiment to determine whether PACAP influences the markers of oxidative stress in vivo. We have proven earlier that PACAP was effective in kidney ischemia/reperfusion injury in vivo. In the present study, we determined the levels of the oxidative stress marker malondialdehyde and the activity of the scavenger molecules glutathione (GSH) and superoxide dismutase (SOD) following kidney ischemia/reperfusion in rats. We found that PACAP significantly increased the level of GSH and counteracted the marked reduction of SOD activity after ischemia/reperfusion in vivo. In summary, the present study showed that while PACAP was able to significantly increase the cell survival in primary kidney cell cultures exposed to oxidative stress, possibly involving interaction with the endogenous scavenger system, it failed to influence the viability of normal or cancerous hepatocytes.
The effects of pituitary adenylate cyclase activating polypeptide (PACAP) are mediated through G-... more The effects of pituitary adenylate cyclase activating polypeptide (PACAP) are mediated through G-protein-coupled receptors, the specific PAC1 receptor and VPAC1 and VPAC2 receptors which bind vasoactive intestinal peptide with similar affinity. Based on binding affinity studies, PACAP6-38 was discovered as a potent antagonist of PAC1 and it has been used by hundreds of studies as a PACAP antagonist. Recently, we have found that in certain cells/tissues, PACAP6-38 does not antagonize PACAP-induced effects, but surprisingly, it exerts similar actions to PACAP1-38, behaving as an agonist. In the present study, we report on the agonistic behavior of PACAP6-38 on neuropeptide release from sensory nerves of the isolated rat trachea and on the MAPK signaling pathways in cytotrophoblast cells. In isolated rat tracheae, PACAP6-38, similarly to PACAP1-38, induced significant inhibitory effects on the release of three simultaneously measured sensory neuropeptides, substance P, calcitonin gene-related peptide, and somatostatin evoked by both chemical excitation and electrical field stimulation of capsaicin-sensitive afferents. Effects of PACAP6-38 were the same as those of PACAP1-38 on MAPK signaling in human cytotrophoblast cells. Western blot analysis showed that both peptide forms stimulated ERK1/2 and JNK phosphorylation, while they both inhibited p38 MAPK phosphorylation. The most pronounced effects were observed when both peptides were present. In summary, our results show that PACAP6-38, which is a PACAP receptor antagonist in most cells/tissues, can behave as an agonist in other systems. The increasing interest in the effects of PACAP requires further studies on the pharmacological properties of the peptide and its analogues.
Objective: To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laborat... more Objective: To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laboratory diagnosis of endometriosis and various gynecologic disorders. Design: Prospective case-control study. Setting: University medical centers. Patient(s): A total of 135 women of reproductive age were involved in the study, 77 endometriosis patients, 28 gynecologic controls, and 30 healthy women. Intervention(s): Diagnostic laparoscopy and collection of tissue biopsies, peritoneal cells, and native peripheral blood from different case groups of gynecology patients and healthy women. Main Outcome Measure(s): The expression of mRNA and serum concentration of Gal-9. Result(s): Semiquantitative reverse transcription-polymerase chain reaction analysis and serum soluble Gal-9 ELISA were performed on three different cohorts of patients: those with endometriosis, those with benign gynecologic disorders, and healthy controls. Differences in the Gal-9 concentrations between the investigated groups and the stability of Gal-9 in the serum and diagnostic characteristics of Gal-9 ELISA were determined by statistical evaluation and receiver operating characteristic (ROC) curve analysis. Significantly elevated Gal-9 levels were found in both minimal-mild (I-II) and moderate-severe (III-IV) stages of endometriosis in comparison with healthy controls. At a cutoff of 132 pg/mL, ROC analysis revealed an excellent diagnostic value of Gal-9 ELISA in endometriosis (area under the curve ¼ 0.973) with a sensitivity of 94% and specificity of 93.75%, indicating better diagnostic potential than that of other endometriosis biomarkers. Furthermore, various pelvic pain or infertility-associated benign gynecologic conditions were also associated with increased serum Gal-9 levels. Conclusion(s): Our results suggest that Gal-9 could be a promising noninvasive biomarker of endometriosis and a predictor of various infertility or pelvic pain-related gynecologic disorders.
Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with survival-promotin... more Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with survival-promoting actions, has been observed in endocrine organs and is thought to play a role in reproductive functions, including pregnancy. PACAP occurs in two forms, 27 and 38 amino acid residues, with PACAP38 being the predominant form in human tissues. In the present study, we determined the concentrations of PACAP38 and PACAP27 in first-trimester and full-term human placentas using radioimmunoassay. We found high levels of PACAP38 and lower levels of PACAP27 in different parts of the full-term human placenta. PACAP38 content increased in the placenta during pregnancy, both on the maternal side and on the fetal side. The effects of PACAP on the survival of JAR human choriocarcinoma cells were investigated using flow cytometry and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell viability assay in cells exposed to the widely used chemotherapeutic agent methotrexate (MTX). It was found that PACAP neither influenced the survival of JAR cytotrophoblast cells nor affected cellular response to the death-inducing effect of the chemotherapeutic agent MTX. The present observations further support the significance of PACAP in the human placenta. The observation that PACAP did not influence the effects of MTX may have future clinical importance, showing that PACAP does not decrease the effects of certain chemotherapeutic agents.
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a widespread neuropeptide with a di... more Pituitary adenylate cyclase-activating polypeptide (PACAP) is a widespread neuropeptide with a diverse array of biological functions. Not surprisingly, the lack of endogenous PACAP therefore results in a variety of abnormalities. One of the important effects of PACAP is its neuroprotective and general cytoprotective role. PACAP protects neurons and other tissues against ischemic, toxic, and traumatic lesions. Data obtained from PACAP-deficient mice provide evidence that endogenous PACAP also has protective functions. Mice lacking PACAP are more vulnerable to different in vitro and in vivo insults. The present review summarizes data on the increased sensitivity of PACAP-deficient mice against harmful stimuli. Mice lacking PACAP respond with a higher degree of injury in cerebral ischemia, autoimmune encephalomyelitis, and axonal lesion. Retinal ischemic and excitotoxic injuries also produce increased cell loss in PACAP-deficient mice. In peripheral organs, kidney cell cultures from PACAP-deficient mice are more sensitive to oxidative stress and in vitro hypoxia.
Follicular growth, ovulation, and luteinization are influenced by interactions of peptide and ste... more Follicular growth, ovulation, and luteinization are influenced by interactions of peptide and steroid hormone-signaling cascades in the ovary. Pituitary adenylate cyclase-activating polypeptide (PACAP) plays an important role in the regulation of several endocrine processes and is present in ovarian follicular fluid (FF). However, little is known about PACAP in FF with regard to maturation, ovulation, fertilization, and successful pregnancy. The aim of this pilot study was to investigate whether there is a correlation between PACAP concentration in FF and ovarian response to superovulation treatment in infertile women, performed in volunteers (n = 132; aged between 20 and 35). After treatment, the number of harvested oocytes was recorded and PACAP immunoreactivity in FF was measured by radioimmunoassay. All the corresponding PACAP concentrations were below 290 fmol/ml in cases when the number of harvested oocytes exceeded 14 per patient, while in all cases above 290 fmol/ml, the number of oocytes was below 14. Using these cutoff values, we determined three study groups: high-PACAP concentration, high-oocyte number, and low-PACAP concentration-low-oocyte number groups. Median values of PACAP concentration in these groups were 411.2, 106.5, and 101.0 fmol/ml, respectively, while the median values of harvested oocytes were 5.5, 19.0, and 5.0, respectively. Differences were significant, indicating a correlation between concentration of PACAP in FF and the number of recruited oocytes. Higher concentrations of PACAP in FF might be associated with lower number of developing oocytes, while low concentrations of PACAP might correlate with a markedly higher number of ova retrieved, thus predicting a higher chance for ovarian hyperstimulation. Our present study is among the first few human clinical studies with direct conclusions drawn for possible clinical impact of PACAP.
Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with well-known cyto... more Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with well-known cytoprotective effects. We have reported earlier that PACAP decreases mortality and the degree of tubular atrophy in a rat model of renal ischemia/reperfusion injury. Recently, we have shown that kidney cultures isolated from PACAP deficient mice show increased susceptibility to renal oxidative stress. Based on these previous studies, we raised the question whether PACAP deficient mice display increased sensitivity to in vivo kidney ischemia/reperfusion. PACAP À/À mice underwent 45 or 60 min of renal ischemia followed by 2 weeks reperfusion. Kidneys were processed for histological analysis. Sections stained with PAS-haematoxylin were graded for the following parameters: degree of tubular dilation, Bowmann's capsule dilation, lymphocyte and macrophage infiltration, thyroidization and the disappearance of the PAS-positive glycocalyx from under the brush border. In other sets of experiments, tissue cytokine expression and the level of the endogenous antioxidant superoxide dismutase (SOD) were also determined after 60 min ischemia/reperfusion. Our results show that while intact kidneys were not different between wild-type and PACAP deficient mice, marked differences were observed in the histological structures in groups that underwent ischemia/reperfusion. PACAP deficient mice had a worse histological outcome, with significantly higher histological scores for all tested parameters. Cytokine expression was also markedly different between wild-type and PACAP deficient mice. In addition, the level of SOD was significantly lower in PACAP À/À animals after ischemia/reperfusion. In conclusion, the lack of endogenous PACAP leads to higher susceptibility to in vivo renal ischemia/reperfusion, suggesting that PACAP has an endogenous renoprotective effect.
Pituitary adenylate cyclase activating polypeptide (PACAP), a multifunctional neuropeptide, has 2... more Pituitary adenylate cyclase activating polypeptide (PACAP), a multifunctional neuropeptide, has 2 active forms, PACAP38 and PACAP27. It is now well-established that PACAP has several actions also in peripheral organs, including renoprotective effects. The peptide itself has not been previously identified in the rat kidney. The first aim of our study was to identify PACAP in the rat kidney using mass spectrometry and radioimmunoassay (RIA).
Although vasoactive intestinal polypeptide (VIP) is thought to be a prolactin releasing factor, i... more Although vasoactive intestinal polypeptide (VIP) is thought to be a prolactin releasing factor, in vivo studies on sheep suggest that it is inactive in this species. Recent studies, based primarily on the rat, suggest that the related pituitary adenylate cyclase-activating polypeptide (PACAP) is also a hypophysiotrophic factor but again in sheep, this peptide has no in vivo effects on hormone secretion despite being a potent activator of adenylate cyclase in vitro. This lack of response to either peptide in vivo in sheep could be due to the low concentration of peptide that reaches the pituitary gland following peripheral injection. In the present study we therefore adopted an alternative approach of evaluating in vitro effects of these peptides on GH, FSH, LH or prolactin secretion from dispersed sheep pituitary cells. In a time-course study, PACAP (1 mmol/l) increased GH concentrations in the culture medium between 1 and 4 h and again at 12 h but had no effect in the 6 and 24 h incubations. Prolactin, LH and FSH were not affected by PACAP. The response to various concentrations of PACAP (1 nmol/l-1 mmol/l) were then evaluated using a 3 h incubation. Again prolactin and LH were not affected by PACAP and there was a small increase in GH concentrations but only at high concentrations of PACAP (0.1 and 1 mmol/l; P<0.05). PACAP also stimulated FSH secretion in cells from some animals although this effect was small. The GH response to PACAP was inhibited by PACAP(6-38), a putative PACAP antagonist, but not by (N-Ac-Tyr1, D-Arg2)-GHRH(1-29)-NH 2, a GH-releasing hormone (GHRH) antagonist. The cAMP antagonist Rp-cAMPS was unable to block the GH response to PACAP suggesting that cAMP does not mediate the secretory response to this peptide. At incubation times from 1-24 h, VIP (1 mmol/l) had no effects on prolactin, LH or GH secretion and, in a further experiment based on a 3 h incubation, concentrations of VIP from 1 nmol/l-1 mmol/l were again without effect on prolactin concentrations. Interactions between PACAP and gonadotrophin releasing hormone (GnRH), GHRH and dopamine were also investigated. PACAP (1 nmol/l-1 mmol/l) did not affect the gonadotrophin or prolactin responses to GnRH or dopamine respectively. However, at a high concentration (1 mmol/l), PACAP inhibited the GH response to GHRH. In summary, these results show that PACAP causes a modest increase in FSH and GH secretion from sheep pituitary cells but only at concentrations of PACAP that are unlikely to be in the physiological range. The present study confirms that VIP is not a prolactin releasing factor in sheep.
Epidemiológiai vizsgálat a húgyuti fejlődési rendellenességek (renalis a/dysgenesis, polí/ multic... more Epidemiológiai vizsgálat a húgyuti fejlődési rendellenességek (renalis a/dysgenesis, polí/ multicystáscystás vesedysplasia, obstruktiv húgyuti rendellenességek és exstrophias húgyhólyag/cloaca) kórokainak feltárása érdekében, a Magyarországi Veleszületett Rendellenességek Eset-Kontroll Felügyelet (Hungarian Case-Control Surveillance of Congenital Abnormlalities) anyagában. A vizsgálat fő céljai:
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Papers by R. Brubel