Possible mechanisms involved in the effect of the subchronic administration of rosuvastatin on endothelial function in rats with metabolic syndrome.

Metabolic syndrome is a multifaceted condition associated with a greater risk of various disorders (e.g., diabetes and heart disease). In a rat model of metabolic syndrome, an acute in vitro application of rosuvastatin causes relaxation of aortic rings. Since the outcome of a subchronic rosuvastatin treatment is unknown, the present study explored its effect on acetylcholine-induced vasorelaxation of aortic rings from rats with metabolic syndrome. Animals were submitted to a 16-week treatment, including a standard diet, a cafeteria-style diet (CAF-diet), or a CAF-diet with daily rosuvastatin treatment (10 mg/kg). After confirming the development of metabolic syndrome in rats, aortic segments were extracted from these animals (those treated with rosuvastatin and untreated) and the acetylcholine-induced relaxant effect on the corresponding rings was evaluated. Concentration-response curves were constructed for this effect in the presence/absence of L-NAME, ODQ, KT 5823, 4-aminopyridine (4-AP), tetraethylammonium (TEA), apamin plus charybdotoxin, glibenclamide, indomethacin, clotrimazole, and cycloheximide pretreatment. Compared to rings from control rats, acetylcholine-induced vasorelaxation decreased in rings from animals with metabolic syndrome, and was maintained at a normal level in animals with metabolic syndrome plus rosuvastatin treatment. The effect of rosuvastatin was inhibited by L-NAME, ODQ, KT 5823, TEA, apamin plus charybdotoxin, but unaffected by 4-AP, glibenclamide, indomethacin, clotrimazole, or cycloheximide. In conclusion, the subchronic administration of rosuvastatin to rats with metabolic syndrome improved the acetylcholine-induced relaxant response, involving stimulation of the NO/cGMP/PKG/Ca2+-activated K+ channel pathway.

Central nervous system development-related microRNAs levels increase in the serum of gestational diabetic women during the first trimester of pregnancy.

MicroRNAs are heterochronic molecules important during brain development, which could be altered by gestational diabetes mellitus (GDM). To explore these molecules in maternal serum, we performed an RT-qPCR analysis. Our results revealed the heterochronic character of some neural development-related microRNA in serum samples of pregnant women. In relation to the first trimester, higher levels of miR-183-5p, -200b-3p, and -125-5p in the second trimester, and higher levels of miR-137 in the third trimester, were found. Furthermore, an insult such as GDM led to higher levels of miR-183-5p, -200b-3p, -125-5p, and -1290 relative to the control in the first trimester, which might be related to changes in neurogenesis and cell proliferation. An in silico analysis suggested that increased microRNAs in the second trimester in the control contributed to cell proliferation and neuron differentiation and that the rise in miR-137 in the third trimester led to neuron maturation. In the diabetic, higher levels of the microRNAs in the first trimester suggested alterations in cell proliferation and neuron differentiation. In conclusion, we showed that fetal-related microRNAs can be detected in the serum of pregnant woman and exhibit temporary regulation during pregnancy and that microRNAs involved in cell proliferation and neuron differentiation are upregulated under GDM.

Altered levels of brain neurotransmitter from new born rabbits with intrauterine restriction.

Fetal intrauterine growth restriction generates chronic hypoxia due to placental insufficiency. Despite the hemodynamic process of blood flow, redistributions are taking place in key organs such as the fetal brain during intrauterine growth restriction, in order to maintain oxygen and nutrients supply. The risk of short- and long-term neurological effects are still present in hypoxic offspring. Most studies previously reported the effect of hypoxia on the levels of a single neurotransmitter, making it difficult to have a better understanding of the relationship among neurotransmitter levels and the defects reported in products that suffer intrauterine growth restriction, such as motor development, coordination and execution of movement, and the learning-memory process. The aim of this study was to evaluate the levels of gamma-aminobutyric acid, glutamate, dopamine and serotonin in three structures of the brain related to the above-mentioned function such as the cerebral cortex, the striatum, and the hippocampus in the chronic hypoxic newborn rabbit model. Our results showed a significant increase in glutamate and dopamine levels in all studied brain structures and a significant decrease in gamma-aminobutyric acid levels but only in the striatum, suggesting that the imbalance on the levels of several neurotransmitters could be involved in new born brain damage due to perinatal hypoxia.

Possible mechanisms involved in the effect of the subchronic administration of rosuvastatin on endothelial function in rats with metabolic syndrome

Metabolic syndrome is a multifaceted condition associated with a greater risk of various disorders (e.g., diabetes and heart disease). In a rat model of metabolic syndrome, an acute in vitro application of rosuvastatin causes relaxation of aortic rings. Since the outcome of a subchronic rosuvastatin treatment is unknown, the present study explored its effect on acetylcholine-induced vasorelaxation of aortic rings from rats with metabolic syndrome. Animals were submitted to a 16-week treatment, including a standard diet, a cafeteria-style diet (CAF-diet), or a CAF-diet with daily rosuvastatin treatment (10 mg/kg). After confirming the development of metabolic syndrome in rats, aortic segments were extracted from these animals (those treated with rosuvastatin and untreated) and the acetylcholine-induced relaxant effect on the corresponding rings was evaluated. Concentration-response curves were constructed for this effect in the presence/absence of L-NAME, ODQ, KT 5823, 4-aminopyridine (4-AP), tetraethylammonium (TEA), apamin plus charybdotoxin, glibenclamide, indomethacin, clotrimazole, and cycloheximide pretreatment. Compared to rings from control rats, acetylcholine-induced vasorelaxation decreased in rings from animals with metabolic syndrome, and was maintained at a normal level in animals with metabolic syndrome plus rosuvastatin treatment. The effect of rosuvastatin was inhibited by L-NAME, ODQ, KT 5823, TEA, apamin plus charybdotoxin, but unaffected by 4-AP, glibenclamide, indomethacin, clotrimazole, or cycloheximide. In conclusion, the subchronic administration of rosuvastatin to rats with metabolic syndrome improved the acetylcholine-induced relaxant response, involving stimulation of the NO/cGMP/PKG/Ca2+-activated K+ channel pathway.

Escherichia coli-induced temporal and differential secretion of heat-shock protein 70 and interleukin-1ß by human fetal membranes in a two-compartment culture system.

INTRODUCTION: Escherichia coli is recognized as an etiological bacteria associated with chorioamnionitis and the preterm premature rupture of fetal membranes. This pathological condition induces pro-inflammatory cytokines and degradative metalloproteinases, which are considered biological markers secreted in an acute stage of infection. Heat-shock proteins (HSPs) are an important component of the innate immunity response and are found in different pathological conditions. They have not been previously measured in human fetal membranes in response to infectious conditions. We hypothesized that the choriodecidual tissue and amniotic epithelium secreted temporal and differential Hsp-60, Hsp-70, and interleukin (IL)-1ß mediated by E. coli infection. METHODS: Fetal membranes were mounted in a two-compartment culture system and infected with two passes of live E. coli at different doses (10², 104, 105, and 106 colony-forming units (CFU)/mL) and intervals of incubation (3, 6, and 24 h). The culture medium was collected, and Hsp-60, Hsp-70, and IL-1ß were assessed using the enzyme-linked immunosorbent assay (ELISA) method. RESULTS: After 3 and 6 h of infection, E. coli induced an increase in Hsp-70 secretion in the choriodecidual tissue. However, after 24 h of incubation, Hsp-70 was downregulated and we observed an increase in IL-1ß secretion. By contrast, E. coli induced a lower Hsp-60 secretion in the amnion compared to Hsp-70. DISCUSSION: Human fetal membranes responded actively to E. coli infection, with an increase in Hsp-70 during the first hours of infection. After 24 h, there was an increase in the liberation of IL-1ß.

An experimental mixed bacterial infection induced differential secretion of proinflammatory cytokines (IL-1ß, TNFα) and proMMP-9 in human fetal membranes.

Overall, 1-4% of all births in the US are complicated by choriamnionitis. Choriamnionitis is a polymicrobial infection most often due to ascending genital microbes which, in over 65% of positive amniotic fluid cultures, involves two or more organisms. In this study, we determine the cytokines expression (IL-1ß, TNFα) and prometalloproteinase activation (proMMP-2 and proMMP-9) after double o single infection an in vitro model of human fetal membranes. Fetal membranes at term were mounted in the Transwell culture system and after 24 h of infection, choriodecidual, and amnion media was collected. IL-1ß and TNFα were evaluated by ELISA, whereas proMMP-9 and proMMP-2 were determined by substrate gel zymography. The choriodecidual and amnion compartments actively respond to the infectious process, which induced the secretion of IL-1ß, TNFα, and proMMP-9 after either mixed or single infection. The proMMP-2 secretion profile was the same after all experimental conditions. There was no synergy between Streptococcus agalactiae and Escherichia coli for inducing the secretion of inflammatory factors or degradative metalloproteinase. In conclusion, these two bacteria could initiate different pathways to induce chorioamnioitis.

Effect of increasing trypsin concentrations on seminal coagulum dissolution and sperm parameters in spider monkeys (Ateles geoffroyi).

Seminal coagulum formation in spider monkeys (Ateles geoffroyi) interferes with the efficient recovery and evaluation of spermatozoa. The main objective was to assess the effect of increasing concentrations of trypsin on dissolution of seminal coagulum and spermatic parameters. Seminal coagulum was incubated at 37 °C without trypsin or in the presence of increasing trypsin concentrations (0.1%, 1.0%, and 5.0%). For each sample, coagulum dissolution time was measured, and sperm concentration, viability, motility, and morphology were evaluated using light microscopy and/or transmission electronic microscopy (TEM). Trypsin concentrations of 1.0% and 5.0% more rapidly liquefied seminal coagulum, averaging 32 and 21 min, respectively, compared with nontrypsinized controls, with maintenance of greater sperm viability (70.8% and 72.5%, respectively). Coagulum treated with 1.0% trypsin and the liquid ejaculate fraction averaged higher sperm motility (40.1% and 55.6%, respectively) than control samples, and both 1.0% and 5.0% trypsin treatment allowed recovery of increased numbers of motile spermatozoa. There was greater sperm fragmentation at the head and midpiece level after treatment with 1.0% and 5.0% trypsin (55.8% and 55.9%); however, the percentage of normal morphology in structurally intact spermatozoa did not differ relative to controls. With transmission electronic microscopy imaging, there were similar percentages of spermatozoa with plasma membrane swelling in the midpiece and acrosomal regions in trypsin-treated samples and controls. In conclusion, trypsin treatment of spider monkey seminal coagulum exerted a concentration-dependent effect on dissolution time and various spermatic parameters. Higher trypsin concentrations caused more rapid liquefaction of coagulum and recovery of greater numbers of motile spermatozoa, but may adversely affect fragmentation of spermatozoa and could compromise sperm function and cryopreservation potential.

Histamine is required during neural stem cell proliferation to increase neuron differentiation.

Histamine in the adult central nervous system (CNS) acts as a neurotransmitter. This amine is one of the first neurotransmitters to appear during development reaching its maximum concentration simultaneously with neuron differentiation peak. This suggests that HA plays an important role in neurogenesis. We have previously shown that HA is able to increase neuronal differentiation of neural stem cells (NSCs) in vitro, by activating the histamine type 1 receptor. However the mechanism(s) by which HA has a neurogenic effect on NSCs has not been explored. Here we explore how HA is able to increase neuron phenotype. Cortex neuroepithelium progenitors were cultured and at passage two treatments with 100 µM HA were given during cell proliferation and differentiation or only during differentiation. Immunocytochemistry was performed on differentiated cultures to detect mature neurons. To explore the expression of certain important transcriptional factors involved on asymmetric cell division and commitment, RT-PCR and qRT-PCR were performed. Results indicate that HA is required during cell proliferation in order to increase neuron differentiation and suggest that this amine increases neuron commitment during the proliferative phase probably by rising prospero1 and neurogenin1 expression.