ABSTRACT
Here, we highlight the case of a 31-yr-old man who had clinical features of primary hypertrophic osteoarthropathy (PHOAR) and harbored a homozygous variant (c.38C > A, p.Ala13Glu) in the HPGD gene, as indicated by whole-exome sequencing (WES). This variant has been previously classified by our laboratory as a variant of uncertain significance (VUS). However, another patient with the same phenotype and the same homozygous variant in HPGD was subsequently reported. In reassessing the variant, the absence of this variant in the gnomAD population database, supporting computational predictions, observation in homozygosity in two probands, and specificity of the phenotype for HPGD, all provide sufficient evidence to reclassify the HPGD c.38C > A, p.Ala13Glu variant as likely pathogenic.
Subject(s)
Osteoarthropathy, Primary Hypertrophic , Male , Humans , Osteoarthropathy, Primary Hypertrophic/diagnosis , Osteoarthropathy, Primary Hypertrophic/genetics , Hydroxyprostaglandin Dehydrogenases/genetics , Homozygote , Phenotype , Exome SequencingABSTRACT
Solidagenone (SOL) is a labdane-type diterpenoid found in Solidago chilensis, a plant traditionally used to treat skin diseases, kidney pain and ovarian inflammation. In this study, the topical anti-inflammatory activity of SOL was evaluated using in vivo and in silico assays. Croton oil-, arachidonic acid (AA)- and phenol-induced ear oedema mouse models were applied in the in vivo studies. Myeloperoxidase (MPO) and N-acetyl-ß-D-glucosaminidase (NAG) activities and tumour necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and nitric oxide (NO) levels were determined, as well as histopathological analyses were conducted. Interaction profiles between SOL and cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), glucocorticoid receptor, estradiol-17-ß-dehydrogenase and prostaglandin-E(2)-9-reductase were established using molecular docking. SOL significantly inhibited croton oil-, AA- and phenol-induced ear oedema (P < .001) at doses of 0.1, 0.5 and 1.0 mg/ear. The MPO and NAG activities and TNF-α, IL-6 and NO levels were decreased (P < .001). The histopathological data revealed that inflammatory parameters (oedema thickness, leucocyte infiltration and vasodilatation) were reduced by treatment with SOL at doses of 0.1, 0.5 and 1.0 mg/ear. The docking study showed that SOL interacts with COX-1 and prostaglandin-E(2)-9-reductase through hydrogen bonding, inhibiting these enzymes. These results indicate that SOL may be a promising compound for the treatment of cutaneous inflammatory disorders and has potential as a topical anti-inflammatory agent.
Subject(s)
Cyclooxygenase Inhibitors/pharmacology , Dermatitis/prevention & control , Edema/prevention & control , Furans/pharmacology , Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors , Membrane Proteins/antagonists & inhibitors , Naphthalenes/pharmacology , Plant Extracts/pharmacology , Skin/drug effects , Solidago , Acetylglucosaminidase/metabolism , Animals , Cyclooxygenase 1/metabolism , Cyclooxygenase Inhibitors/isolation & purification , Cyclooxygenase Inhibitors/metabolism , Dermatitis/metabolism , Dermatitis/pathology , Disease Models, Animal , Edema/chemically induced , Edema/metabolism , Edema/pathology , Furans/isolation & purification , Furans/metabolism , Hydrogen Bonding , Hydroxyprostaglandin Dehydrogenases/metabolism , Interleukin-6/metabolism , Male , Membrane Proteins/metabolism , Mice , Molecular Docking Simulation , Naphthalenes/isolation & purification , Naphthalenes/metabolism , Nitric Oxide/metabolism , Peroxidase/metabolism , Plant Extracts/isolation & purification , Plant Extracts/metabolism , Protein Binding , Signal Transduction , Skin/metabolism , Skin/pathology , Solidago/chemistry , Tumor Necrosis Factor-alpha/metabolismABSTRACT
BACKGROUND: Aspirin is a promising medical therapy for the prevention of intracranial aneurysm (IA) rupture. Recently, we found that men have a better response to aspirin than women. The purpose of this study was to determine whether a sex differential exists in the level of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in the lumen of human IAs. METHODS AND RESULTS: Consecutive patients undergoing coiling or stent-assisted coiling for a saccular IA at our institution were enrolled. Two samples (A and B) were collected from IA lumens, and the plasma level of 15-PGDH was measured using an ELISA-based method. The study included 38 patients, with 20 women and 18 men. Women and men were comparable on baseline characteristics. The mean plasma concentration of 15-PGDH did not differ statistically between sample A (62.8±16.2 ng/mL) and sample B (61.8±17.9 ng/mL; 95% confidence interval -6.6 to 9.4). The mean plasma concentration of 15-PGDH in IA lumens of samples A and B was significantly higher in men (73.8±13.5 ng/mL) than women (49.6±7.8 ng/mL; P<0.0001). CONCLUSIONS: Higher enzyme levels of 15-PGDH exist in the lumen of IAs of men compared with women. This observation could explain why aspirin confers better protection against IA rupture in men than in women. The susceptibility of an individual to aspirin may differ according to the level of 15-PGDH.
Subject(s)
Hydroxyprostaglandin Dehydrogenases/blood , Intracranial Aneurysm/enzymology , Adult , Aged , Aspirin/therapeutic use , Biomarkers/blood , Cardiovascular Agents/therapeutic use , Embolization, Therapeutic/instrumentation , Female , Humans , Intracranial Aneurysm/blood , Intracranial Aneurysm/diagnosis , Intracranial Aneurysm/therapy , Male , Middle Aged , Sex Factors , Stents , Up-RegulationABSTRACT
Endometritis is a major cause of infertility in many domestic species. However, until now the pathogenesis of the endometritis in the bitch is unclear. The aim of this study was to evaluate the gene transcription pattern of prostaglandin (PG) synthesis enzymes (cyclooxygenase [COX2], PTGES-1 and PGFS) in the endometrium of bitches with or without endometritis. Thirty mixed breed bitches in dioestrus, aged between 1 and 5 years, and weighing between 10 and 30 kg were used. After ovariohysterectomy (OVX), uterine biopsy samples were collected from the middle part of both horns. Then, endometrial epithelium was collected using the cytobrush method and mRNA analysis was performed by real-time RT-PCR. Data were analysed with Kruskal-Wallis anova using the sas® software. Uterine condition was identified by endometrial biopsies (normal endometria [n = 11; NE], acute endometritis [n = 10; AE] and chronic endometritis [n = 9; CE]). The COX2, PTGES-1 and PGFS/AKR1C3 mRNA expression in bitches with and without endometritis was similar. Except for PGFS/AKR1C3, gene transcription of COX2 and PTGES-1 was significantly increased in AE compared with CE. In addition, COX2 gene transcription was significantly increased in AE compared with NE. In contrast, no differences were found for COX2, PTGES-1 and PGFS/AKR1C3 mRNA expression in the samples of NE compared with CE.
Subject(s)
Dog Diseases/enzymology , Endometritis/veterinary , Endometrium/enzymology , Prostaglandins/biosynthesis , Prostaglandins/genetics , Transcription, Genetic , Animals , Cyclooxygenase 2/genetics , Dog Diseases/surgery , Dogs , Endometritis/enzymology , Endometritis/surgery , Female , Hydroxyprostaglandin Dehydrogenases/genetics , Hysterectomy/veterinary , Ovariectomy/veterinary , Prostaglandin-E Synthases/genetics , RNA, Messenger/analysisABSTRACT
BACKGROUND: In 21-hydroxylase deficiency (21-OHD), there is an influence of genotype on the severity of external genitalia virilization. However, females carrying mutations predicting a similar impairment of enzymatic activity present a wide variability of genital phenotypes. In such cases, interindividual variability in genes related to the sex steroid hormone pathway could play a role. OBJECTIVE: To evaluate the influence of POR, HSD17B5 and SRD5A2 variants on the severity of external genitalia virilization in 21-OHD females. DESIGN AND PATIENTS: Prader stages were evaluated in 178 females with 21-OHD from a multicenter study. The 21-OHD genotypes were divided into two groups according to their severity: severe and moderate. The influences of the POR p.A503V, HSD17B5 c.-71A>G, HSD17B5 c.-210A>C, and SRD5A2 p.A49T and p.V89L variants on the degree of external genitalia virilization were analyzed. RESULTS: The POR p.A503V, HSD17B5 c.-71A>G, HSD17B5 c.-210A>C, and SRD5A2 p.A49T and p.V89L variants were found in 25, 33, 17, 1, and 31% of the alleles, respectively. In uni- and multilinear regression, HSD17B5 c.-210A>C has a significant influence on the degree of external genitalia virilization. This variant was also identified with a higher frequency in the most severely virilized females. CONCLUSION: We demonstrated that a variant in the promoter region of HSD17B5 related to fetal androgen synthesis influences the genital phenotype in 21-OHD females.
Subject(s)
3-Hydroxysteroid Dehydrogenases/genetics , Adrenal Hyperplasia, Congenital/genetics , Alleles , Hydroxyprostaglandin Dehydrogenases/genetics , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Virilism/genetics , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/genetics , Adrenal Hyperplasia, Congenital/pathology , Aldo-Keto Reductase Family 1 Member C3 , Female , Humans , Membrane Proteins/genetics , Retrospective Studies , Virilism/pathologyABSTRACT
The initial inactivation of prostaglandins (PGs) is mediated by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). PGs are potent mediators of several biological processes, including inflammation and reproduction. In uterus, PGs play a key role in infection-induced pregnancy loss, in which concentration of this mediator increased. This process is accompanied with the induction of nitric oxide synthase expression and a marked increase in uterine levels of nitric oxide. There is no information concerning nitric oxide contribution to potential changes in PG catabolism, but experimental evidence suggests that nitric oxide modulates PG pathways. The specific objectives of the study were to evaluate the protein expression of HPGD (15-PGDH) and to characterize the nitric oxide-dependent regulation of this enzyme in a model of lipopolysaccharide (LPS)-induced embryonic resorption. Results show that LPS decreased HPGD protein expression and augmented PGE synthase activity; therefore, PGE2 levels increased in uterus in this inflammatory condition. Just as LPS, the treatment with a nitric oxide donor diminished HPGD protein expression in uterine tissue. In contrast, the inhibition of nitric oxide synthesis both in control and in LPS-treated mice increased 15-PGDH levels. Also, we have found that this enzyme and PGE2 levels are not modulated by peroxynitrite, an oxidant agent derived from nitric oxide. This study suggests that LPS and nitric oxide promote a decrease in the ability of the uterus for PG catabolism during bacterially triggered pregnancy loss in mice.
Subject(s)
Down-Regulation , Embryo Loss/metabolism , Hydroxyprostaglandin Dehydrogenases/metabolism , Nitric Oxide/metabolism , Uterus/metabolism , Animals , Dinoprostone/metabolism , Down-Regulation/drug effects , Embryo Loss/enzymology , Embryo Loss/immunology , Enzyme Inhibitors/pharmacology , Escherichia coli Infections/enzymology , Escherichia coli Infections/immunology , Escherichia coli Infections/metabolism , Female , Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors , Intramolecular Oxidoreductases/metabolism , Lipopolysaccharides , Mice , Mice, Inbred BALB C , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Pregnancy , Pregnancy Complications, Infectious/enzymology , Pregnancy Complications, Infectious/immunology , Pregnancy Complications, Infectious/metabolism , Prostaglandin-E Synthases , Random Allocation , Up-Regulation/drug effects , Uterus/drug effects , Uterus/immunologyABSTRACT
The human aldo-keto reductase (AKR) 1C3, also known as type-5 17ß-hydroxysteroid dehydrogenase and prostaglandin F synthase, has been suggested as a therapeutic target in the treatment of prostate and breast cancers. In this study, AKR1C3 inhibition was examined by Brazilian propolis-derived cinnamic acid derivatives that show potential antitumor activity, and it was found that baccharin (1) is a potent competitive inhibitor (K(i) 56 nM) with high selectivity, showing no significant inhibition toward other AKR1C isoforms (AKR1C1, AKR1C2, and AKR1C4). Molecular docking and site-directed mutagenesis studies suggested that the nonconserved residues Ser118, Met120, and Phe311 in AKR1C3 are important for determining the inhibitory potency and selectivity of 1. The AKR1C3-mediated metabolism of 17-ketosteroid and farnesal in cancer cells was inhibited by 1, which was effective from 0.2 µM with an IC(50) value of about 30 µM. Additionally, 1 suppressed the proliferation of PC3 prostatic cancer cells stimulated by AKR1C3 overexpression. This study is the first demonstration that 1 is a highly selective inhibitor of AKR1C3.
Subject(s)
3-Hydroxysteroid Dehydrogenases/antagonists & inhibitors , Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors , Propolis/chemistry , Trichothecenes/pharmacology , Aldo-Keto Reductase Family 1 Member C3 , Brazil , Crystallography, X-Ray , Humans , Male , Molecular Conformation , Nuclear Magnetic Resonance, Biomolecular , Stereoisomerism , Trichothecenes/chemistryABSTRACT
We studied (1) the effects of oral contraceptive pills (OCPs) on hirsutism, hormonal and metabolic variables in 49 polycystic ovary syndrome patients without metabolic comorbidities and (2) the effect of 17-hydroxysteroid dehydrogenase type 5 gene polymorphism (-71A/G HSD17B5 SNP) on the response to OCP treatment. Mean age was 21.9 ± 6.5 years. Patients received monophasic OCP (20 µg ethinyl estradiol plus 75 µg gestodene), 21/28 days per cycle, during 6 months; 32 patients with severe hirsutism also received spironolactone 100 mg. The frequencies of HSD17B5 genotypes were: AA = 0.49 (55.1%), AG = 0.42 (30.6%) and GG = 0.09 (14.3%). After 6 months, body mass index and waist circumference remained unchanged regardless of the presence of allele G. A slight reduction (p < 0.05) was noted in systolic blood pressure (p < 0.05) and luteinizing hormone levels, whereas a slight increase (p < 0.05) was noted in lipids. Total testosterone and hirsutism score declined, while sex hormone binding globulin increased after OCP treatment (p < 0.05). None of these changes were associated with genotype. Insulin and homeostasis model assessment remained unchanged after treatment and did not vary according to the presence of allele G. OCP seems to ameliorate androgenic symptoms without compromising metabolic parameters. The -71A/G SNP of HSD17B5 gene did not contribute to the improvements observed.
Subject(s)
Contraceptives, Oral, Combined/therapeutic use , Ethinyl Estradiol/therapeutic use , Hirsutism/prevention & control , Norpregnenes/therapeutic use , Polycystic Ovary Syndrome/drug therapy , Sex Hormone-Binding Globulin/analysis , Testosterone/blood , 3-Hydroxysteroid Dehydrogenases/genetics , 3-Hydroxysteroid Dehydrogenases/metabolism , Adolescent , Adult , Aldo-Keto Reductase Family 1 Member C3 , Brazil , Contraceptives, Oral, Combined/adverse effects , Drug Therapy, Combination , Ethinyl Estradiol/adverse effects , Female , Genetic Association Studies , Hirsutism/drug therapy , Hirsutism/etiology , Hirsutism/physiopathology , Humans , Hydroxyprostaglandin Dehydrogenases/genetics , Hydroxyprostaglandin Dehydrogenases/metabolism , Hyperandrogenism/etiology , Hyperandrogenism/prevention & control , Mineralocorticoid Receptor Antagonists/therapeutic use , Norpregnenes/adverse effects , Pilot Projects , Polycystic Ovary Syndrome/genetics , Polycystic Ovary Syndrome/metabolism , Polycystic Ovary Syndrome/physiopathology , Polymorphism, Single Nucleotide , Severity of Illness Index , Spironolactone/therapeutic use , Young AdultABSTRACT
The first proteomic analysis of Trypanosoma cruzi resistance to Benznidazole (BZ) is presented. The differential proteome of T. cruzi with selected in vivo resistance to Benznidazole (BZR and Clone27R), its susceptible pairs (BZS and Clone9S), and a pair from a population with Benznidazole- in vitro-induced resistance (17LER) and the susceptible pair 17WTS were analyzed by two-dimensional gel electrophoresis (2-DE) followed by mass spectrometry (MS) for protein identification. Out of 137 spots analyzed through MS, 110 were identified as 56 distinct proteins. Out of the 56 distinct proteins, 36 were present in resistant, 9 in susceptible, and 11 in both phenotypes. Among the proteins identified in resistant samples, 5 were found in Cl 27R and in BZR (calpain-like cysteine peptidase, hypothetical protein conserved 26 kDa, putative peptidase, peroxiredoxin and tyrosine amino transferase) and 4 in Cl 27R and 17LER (cyclophilin A, glutamate dehydrogenase, iron superoxide dismutase and nucleoside diphosphate kinase). As for the proteins identified in Benznidazole-susceptible samples, PGF-2a was found in BZS and 17WTS. A functional category analysis showed that the proteins involved with transcription and protein destination were overexpressed for the Benznidazole-resistant phenotype. Thus, the present study provides large-scale, protein-related information for investigation of the mechanism of T. cruzi resistance to Benznidazole.
Subject(s)
Drug Resistance , Nitroimidazoles/pharmacology , Proteome/metabolism , Protozoan Proteins/metabolism , Trypanosoma cruzi/metabolism , Animals , Cyclophilin A/analysis , Cyclophilin A/metabolism , Cysteine Endopeptidases/analysis , Cysteine Endopeptidases/metabolism , Electrophoresis, Gel, Two-Dimensional , Glutamate Dehydrogenase/analysis , Glutamate Dehydrogenase/metabolism , Hydroxyprostaglandin Dehydrogenases/analysis , Hydroxyprostaglandin Dehydrogenases/metabolism , Nucleoside-Diphosphate Kinase/analysis , Nucleoside-Diphosphate Kinase/metabolism , Peptide Hydrolases/analysis , Peptide Hydrolases/metabolism , Peroxiredoxins/analysis , Peroxiredoxins/metabolism , Proteome/analysis , Protozoan Proteins/analysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Superoxide Dismutase/analysis , Superoxide Dismutase/metabolism , Tandem Mass Spectrometry , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Tyrosine Transaminase/analysis , Tyrosine Transaminase/metabolismABSTRACT
Nitric oxide (NO) synthesized by fetal membranes may act either directly inhibiting myometrium contractility or indirectly interacting with tocolytic agents as prostaglandins (PGs). Here we examined if NO could modulate prostaglandin E(2) 9-ketoreductase (9-KPR) activity in human fetal membranes (HFM). 9-KPR is the enzyme that converts PGE(2) into PGF(2alpha), the main PGs known to induce uterine contractility at term. Chorioamnion explants obtained from elective caesareans were incubated with aminoguanidine (AG), an iNOS inhibitor, or NOC-18, a NO donor. NOC-18 (2mM) increased PGE(2) production and diminished PGF(2alpha) synthesis in HFM. AG presented the opposite effect. When we evaluated the activity of 9-KPR by the conversion of [(3)H]-PGE(2) into [(3)H]-PGF(2alpha) and 13,14-dihidro-15-keto prostaglandin F(2alpha) (the PGF(2alpha) metabolite), we found that NOC-18 inhibited 9-KPR activity. Interestingly, AG did not elicit any effect on 9-KPR but l-NAME, a non-selective NOS inhibitor, significantly increased its activity. Our data suggests that exogenous NO inhibits 9-KPR activity in HFM, thus modulating the synthesis of important labor mediators as PGF(2alpha).
Subject(s)
Extraembryonic Membranes/enzymology , Hydroxyprostaglandin Dehydrogenases/metabolism , Nitric Oxide/metabolism , Dinoprost/metabolism , Dinoprostone/metabolism , Dose-Response Relationship, Drug , Extraembryonic Membranes/cytology , Extraembryonic Membranes/drug effects , Female , Gene Expression Regulation , Humans , Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors , Middle Aged , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase/metabolism , Pregnancy , Prostaglandin-Endoperoxide Synthases/metabolismABSTRACT
Myometrial quiescence is a key factor in all species to accomplish a successful gestation. PGs play a crucial role in mediating parturition events, and their synthesis and metabolism are regulated by cyclooxygenases (COXs) and NAD(+)-dependent 15-hydroxy-PG dehydrogenase (PGDH), respectively. Progesterone (P(4)) is the hormone responsible for maintaining uterine smooth muscle quiescence during pregnancy. In this work, we have studied the effect of P(4) on the activity of COXs and PGDH, the uterine enzymes involved in the biosynthesis and metabolism of prostanoids in the rat. We found that during pregnancy PGF(2alpha) production and also protein levels of COX-1 and COX-2 were decreased. The exogenous administration of P(4) significantly inhibited the uterine production of PGF(2alpha) and also the protein level of COX-2. PGF(2alpha), metabolism was assessed by PGDH activity, which resulted high during pregnancy and increased as a result of P(4) administration. These results indicate that PGs levels were negatively modulated by P(4), which could be exerting its effect by increasing PGs metabolism through stimulation on PGDH activity and an inhibition on COX and that is a major mechanism for maintain uterine quiescence in pregnancy.
Subject(s)
Abortifacient Agents, Nonsteroidal/metabolism , Dinoprost/metabolism , Progesterone/pharmacology , Uterus/drug effects , Animals , Cyclooxygenase 1 , Cyclooxygenase 2 , Female , Hydroxyprostaglandin Dehydrogenases/metabolism , Isoenzymes/metabolism , Membrane Proteins , Pregnancy , Prostaglandin-Endoperoxide Synthases/metabolism , Rats , Rats, Wistar , Uterus/metabolismABSTRACT
The anti-inflammatory effects of Ph CL28A, a potentiator of prostacyclin output and inhibitor of leukotriene (LT) synthesis, were assessed in two models of acute inflammation. In paw oedema induced by carrageenan in rats, Ph CL28A (10-100 mg/kg), given i.p. at the same time as the carrageenan, inhibited oedema for up to 4 h. When indomethacin or Ph CL28A was given locally into the paw with carrageenan, indomethacin inhibited oedema formation but Ph CL28A potentiated the oedema for up to 4 h. As Ph CL28A does not inhibit cyclo-oxygenase, its anti-inflammatory effects in this model may reflect its ability to increase prostacyclin output. In pleurisy induced by carrageenan in rats, there were increases in leukocytes, LTB4, thromboxane B2 (TxB2) and 6-oxo-prostaglandin F1 alpha (6-oxo-PGF1 alpha) in the pleural fluid over 3 h. In this model, Ph CL28A (30 mg/kg) given i.p. decreased leukocyte numbers and LTB4 but did not affect TxB2 or 6-oxo-PGF1 alpha. Indomethacin decreased both prostanoids but did not affect leukocyte accumulation. The beneficial effects of Ph CL28A in two different models of acute inflammation suggests that it may have potential as an anti-inflammatory agent.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Azo Compounds/pharmacology , Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors , 6-Ketoprostaglandin F1 alpha/biosynthesis , Animals , Blood Pressure/drug effects , Carrageenan , Edema/chemically induced , Edema/prevention & control , Epoprostenol/biosynthesis , Indomethacin/pharmacology , Leukotriene B4/biosynthesis , Male , Pleurisy/chemically induced , Pleurisy/prevention & control , Radioimmunoassay , Rats , Rats, Wistar , Thromboxane B2/biosynthesisABSTRACT
The effects of exogenous histamine (H) on prostaglandin (PG) generation and release in uteri isolated from diestrous rats and the influences of H2-receptors blockers (cimetidine and metiamide) on the output of uterine PGs, were explored. Moreover, the action of H on the uterine 9-keto-reductase, was also studied. Histamine (10(-4) M) failed to alter the basal output of PGE1 but reduced significantly the generation and release of PGE2 and augmented the output of PGF2 alpha. On the other hand, cimetidine (10(-5) M) enhanced the basal release of PGE2 but had no action on the outputs of PGs E1 or F2 alpha. The enhancing effect of H on the production and release of PGF2 alpha was abolished in the presence of cimetidine. Also, the antagonist reversed the influence of H on the output of PGE2. Metiamide, another H2-receptor antagonist, did not alter the basal control generation and release of uterine PGs, but antagonized the augmenting influence of H on PGF2 alpha uterine output, as much as cimetidine did, and prevented the depressive action of H on the release of PGE2 from uteri. Histamine (10(-4) M) significantly stimulated uterine formation of cyclic-adenosine monophosphate, an action which was antagonized by the presence of cimetidine (10(-5) M), a blocker of H2 receptors. Also, histamine (10(-5) M) and dibutyrylcyclic-adenosine monophosphate (DB-cAMP) at 10(-3) M, enhanced significantly the formation 3H-PGF2 alpha from 3H-PGE2. Results presented herein demonstrate that H is able to diminish the generation of PGE2 in uteri from rats at diestrus augmenting the synthesis of PGF2 alpha, apparently via the activation of H2-receptors, enhancing adenylate-cyclase. These effects appear to increase uterine 9-keto-reductase activity which transforms PGE2 into PGF2 alpha. Relationships between the foregoing results and those evoked by estradiol, are also discussed.
Subject(s)
Diestrus/metabolism , Estrus/metabolism , Histamine/pharmacology , Hydroxyprostaglandin Dehydrogenases/metabolism , Prostaglandins/biosynthesis , Receptors, Histamine H2/drug effects , Uterus/metabolism , Animals , Cimetidine/pharmacology , Cyclic AMP/metabolism , Estradiol/metabolism , Female , In Vitro Techniques , Metiamide/pharmacology , Rats , Rats, Inbred StrainsABSTRACT
The generation and output of prostaglandins (PGs) E2 and F2 alpha into the solution suspending uterine segments from ethanol (ETOH)-fed diestrous rats and the activity of 15-OH-PG-dehydrogenase (PGDH) in uteri at diestrus, were explored and compared with normal-fed controls. Animals were fed with ETOH (35% of the total calories in a liquid diet) during 20 days before sacrifice. Paired normal-fed controls were given isocaloric quantities of dextrimaltose. It was observed that the uterine outputs of PGE2 and of PGF2 alpha into the suspending solution, were significantly greater in the ETOH group. On the other hand, the PGDH activity for PGE2 in control uterine tissue, was significantly smaller than the activity detected in preparations from animals fed with the chronic ETOH diet. Results are discussed in terms of possible mechanisms for the action of ethanol, either on the release of PG fatty acid precursors (activation of phospholipase A2) or on the activity of PG synthesizing enzymes. Inasmuch as in the ETOH-fed group uterine PGDH activity was greater, rather than diminished, the possibility of a reduced catabolism accounting for the augmentation of PGs in the suspending medium, does not appear feasible. In fact, results suggest that the real magnitude of higher PG generation and release is even greater than that disclosed by the present study. The finding that chronic ethanol consumption augments PG production, appears relevant, in view of the unique roles played by these eicosanoids in parturition and in the development of fetuses.