Artigos - Farmacologia - IBB

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Sildenafil attenuates oxidative stress and endothelial dysfunction in lead-induced hypertension
(2023-01-01) Caetano, Ediléia Souza Paula [UNESP]; Mattioli, Sarah Viana [UNESP]; da Silva, Maria Luiza Santos [UNESP]; Martins, Laisla Zanetoni [UNESP]; Almeida, Alaor Aparecido [UNESP]; da Rocha, Ananda Lini Vieira [UNESP]; Nunes, Priscila Rezeck [UNESP]; Grandini, Núbia Alves [UNESP]; Correa, Camila Renata [UNESP]; Zochio, Gabriela Palma [UNESP]; Dias-Junior, Carlos Alan [UNESP]; Universidade Estadual Paulista (UNESP)
Lead (Pb) reduces NO bioavailability, impairs the antioxidant system, and increases the generation of reactive oxygen species (ROS). Pb-induced oxidative stress may be responsible for the associated endothelial dysfunction. Sildenafil has shown nitric oxide (NO)-independent action, including antioxidant effects. Therefore, we examined the effects of sildenafil on oxidative stress, reductions of NO and endothelial dysfunction in Pb-induced hypertension. Wistar rats were distributed into three groups: Pb, Pb + sildenafil and Sham. Blood pressure and endothelium-dependent vascular function were recorded. We also examined biochemical determinants of lipid peroxidation and antioxidant function. ROS levels, NO metabolites and NO levels in human umbilical vein endothelial cells (HUVECs) were also evaluated. Sildenafil prevents impairment of endothelium-dependent NO-mediated vasodilation and attenuates Pb-induced hypertension, reduces ROS formation, enhances superoxide dismutase (SOD) activity and antioxidant capacity in plasma and increases NO metabolites in plasma and HUVECs culture supernatants, while no changes were found on measurement of NO released from HUVECs incubated with plasma of the Pb and Pb + sildenafil groups compared with the sham group. In conclusion, sildenafil protects against ROS-mediated inactivation of NO, thus preventing endothelial dysfunction and attenuating Pb-induced hypertension, possibly through antioxidant effects.
Sevoflurane and isoflurane anesthesia induce redox imbalance, but only sevoflurane impairs vascular contraction
(2023-01-01) Rocha, Thalita L. A. [UNESP]; Borges, Teubislete F. [UNESP]; Rodrigues, Serginara D. [UNESP]; Martins, Laisla Z. [UNESP]; da Silva, Maria L. S. [UNESP]; Bonacio, Gisele F.; Rizzi, Elen; Dias-Junior, Carlos A. [UNESP]; Universidade Estadual Paulista (UNESP); UNAERP
Volatile anesthetics may cause vascular dysfunction; however, underlying effects are unclear. The aim of the present study was to investigate whether sevoflurane and isoflurane affect vascular function, nitric oxide (NO) bioavailability, and biomarkers of oxidative stress and inflammation. Wistar rats were divided into three experimental groups: Not anesthetized (control group) or submitted to anesthesia with isoflurane (Iso group) or sevoflurane (Sevo group). Hemodynamic parameters were monitored during anesthesia, and blood gas values and biochemical determinants were analyzed. Isometric contractions were recorded in aortic rings. Vasoconstriction induced by potassium chloride (KCl) and phenylephrine (Phe) were measured. No differences in hemodynamic parameters and blood gasses variables were observed. Impaired KCl and Phe-induced contractions were observed in endothelium-intact aorta of Sevo compared to Iso and Control groups. Redox imbalance was found in Sevo and Iso groups. Reduced NO bioavailability and increased activity of matrix metalloproteinase 2 (MMP-2) were observed in Sevo, but not in the Iso group. While reduced IL-10 and IL-1β were observed in Sevo, increases in IL-1β in the Iso group were found. Sevoflurane, but not isoflurane, anesthesia impairs vasocontraction, and reduced NO and cytokines and increased MMP-2 activity may be involved in vascular dysfunction after sevoflurane anesthesia.
Acquisition and maintenance of pluripotency are influenced by fibroblast growth factor, leukemia inhibitory factor, and 2i in bovine-induced pluripotent stem cells
(2022-09-14) Botigelli, Ramon Cesar [UNESP]; Pieri, Naira Carolina Godoy; Bessi, Brendon William; Machado, Lucas Simões; Bridi, Alessandra; de Souza, Aline Fernanda; Recchia, Kaiana; Neto, Paulo Fantinato; Ross, Pablo Juan; Bressan, Fabiana Fernandes; Nogueira, Marcelo Fábio Gouveia [UNESP]; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP); University of Guelph; Davis
Several opportunities for embryo development, stem cell maintenance, cell fate, and differentiation have emerged using induced pluripotent stem cells (iPSCs). However, the difficulty in comparing bovine iPSCs (biPSCs) with embryonic stem cells (ESCs) was a challenge for many years. Here, we reprogrammed fetal fibroblasts by transient expression of the four transcription factors (Oct4, Sox2, Klf4, and c-Myc, collectively termed “OSKM” factors) and cultured in iPSC medium, supplemented with bFGF, bFGF2i, leukemia inhibitory factor (LIF), or LIF2i, and then compared these biPSC lines with bESC to evaluate the pluripotent state. biPSC lines were generated in all experimental groups. Particularly, reprogrammed cells treated with bFGF were more efficient in promoting the acquisition of pluripotency. However, LIF2i treatment did not promote continuous self-renewal. biPSCs (line 2) labeled with GFP were injected into early embryos (day 4.5) to assess the potential to contribute to chimeric blastocysts. The biPSC lines show a pluripotency state and are differentiated into three embryonic layers. Moreover, biPSCs and bESCs labeled with GFP were able to contribute to chimeric blastocysts. Additionally, biPSCs have shown promising potential for contributing to chimeric blastocysts and for future studies.
Advances in non-hormonal male contraception targeting sperm motility
(Oxford Univ Press, 2023-05-04) Mariani, Noemia A. P. [UNESP]; Silva, Joana; Fardilha, Margarida; Silva, Erick J. R. [UNESP]; Universidade Estadual Paulista (UNESP); Univ Aveiro; Univ Porto
BACKGROUND The high rates of unintended pregnancy and the ever-growing world population impose health, economic, social, and environmental threats to countries. Expanding contraceptive options, including male methods, are urgently needed to tackle these global challenges. Male contraception is limited to condoms and vasectomy, which are unsuitable for many couples. Thus, novel male contraceptive methods may reduce unintended pregnancies, meet the contraceptive needs of couples, and foster gender equality in carrying the contraceptive burden. In this regard, the spermatozoon emerges as a source of druggable targets for on-demand, non-hormonal male contraception based on disrupting sperm motility or fertilization. OBJECTIVE AND RATIONALE A better understanding of the molecules governing sperm motility can lead to innovative approaches toward safe and effective male contraceptives. This review discusses cutting-edge knowledge on sperm-specific targets for male contraception, focusing on those with crucial roles in sperm motility. We also highlight challenges and opportunities in male contraceptive drug development targeting spermatozoa. SEARCH METHODS We conducted a literature search in the PubMed database using the following keywords: 'spermatozoa', 'sperm motility', 'male contraception', and 'drug targets' in combination with other related terms to the field. Publications until January 2023 written in English were considered. OUTCOMES Efforts for developing non-hormonal strategies for male contraception resulted in the identification of candidates specifically expressed or enriched in spermatozoa, including enzymes (PP1 gamma 2, GAPDHS, and sAC), ion channels (CatSper and KSper), transmembrane transporters (sNHE, SLC26A8, and ATP1A4), and surface proteins (EPPIN). These targets are usually located in the sperm flagellum. Their indispensable roles in sperm motility and male fertility were confirmed by genetic or immunological approaches using animal models and gene mutations associated with male infertility due to sperm defects in humans. Their druggability was demonstrated by the identification of drug-like small organic ligands displaying spermiostatic activity in preclinical trials. WIDER IMPLICATIONS A wide range of sperm-associated proteins has arisen as key regulators of sperm motility, providing compelling druggable candidates for male contraception. Nevertheless, no pharmacological agent has reached clinical developmental stages. One reason is the slow progress in translating the preclinical and drug discovery findings into a drug-like candidate adequate for clinical development. Thus, intense collaboration among academia, private sectors, governments, and regulatory agencies will be crucial to combine expertise for the development of male contraceptives targeting sperm function by (i) improving target structural characterization and the design of highly selective ligands, (ii) conducting long-term preclinical safety, efficacy, and reversibility evaluation, and (iii) establishing rigorous guidelines and endpoints for clinical trials and regulatory evaluation, thus allowing their testing in humans.
Artificial intelligence blastocyst ploidy distinction through morphokinetics data
(Oxford Univ Press, 2022-07-01) Nicolielo Barreto, M.; Jacobs, C.; Souza, R. C. M. [UNESP]; Erberelli, R.; Alegretti, J. R.; Chehin, M. B.; Motta, E. L. A.; Nogueira, M. F. G. [UNESP]; Rocha, J. C. [UNESP]; Lorenzon, A. R.; Huntington Med Reprod Eugin Grp; Universidade Estadual Paulista (UNESP); Universidade Federal de São Paulo (UNIFESP)
Use of giant unilamellar lipid vesicles as antioxidant carriers in in vitro culture medium of bovine embryos
(2022-12-01) Rossi, Luana Teixeira Rodrigues [UNESP]; Nunes, Giovana Barros [UNESP]; da Silva, Cíntia Rodrigues [UNESP]; de Rossi, Hugo [UNESP]; dos Santos, Priscila Helena [UNESP]; Nogueira, Marcelo Fábio Gouveia [UNESP]; Aoki, Pedro Henrique Benites [UNESP]; Mingoti, Gisele Zoccal [UNESP]; Universidade Estadual Paulista (UNESP)
Giant unilamellar vesicles (GUVs) are composed of lipophilic layers and are sensitive to the action of reactive oxygen species (ROS). The use of GUVs as microcarriers of biological macromolecules is particularly interesting since ROS produced by gametes or embryos during in vitro culture can induce the opening of pores in the membrane of these vesicles and cause the release of their content. This study investigated the behavior of GUVs [composed of 2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl)] in co-culture with in vitro produced bovine embryos, as well as their embryotoxicity and effectiveness as cysteine carriers in culture medium. Embryonic developmental rates were unaffected, demonstrating the absence of toxicity of GUVs co-cultured with the embryos. No increase of intracellular ROS levels was observed in the embryos co-cultured with GUVs, indicating that the higher lipid content of the culture environment resulting from the lipid composition of the GUV membrane itself did not increase oxidative stress. Variations in the diameter and number of GUVs demonstrated their sensitivity to ROS produced by embryos cultured under conditions that generate oxidative stress. Encapsulation of cysteine in GUVs was found to be more effective in controlling the production of ROS in embryonic cells than direct dilution of this antioxidant in the medium. In conclusion, the use of GUVs in in vitro culture was found to be safe since these vesicles did not promote toxic effects nor did they increase intracellular ROS concentrations in the embryos. GUVs were sensitive to oxidative stress, which resulted in structural changes in response to the action of ROS. The possible slow release of cysteine into the culture medium by GUV rupture would therefore favor the gradual supply of cysteine, prolonging its presence in the medium. Thus, the main implication of the use of GUVs as cysteine microcarriers is the greater effectiveness in preventing the intracytoplasmic increase of ROS in in vitro produced bovine embryos.
Analysis of the associations of the T-786C and Glu298Asp polymorphisms of the eNOS gene as risk factors in the rupture of intracranial aneurysms
(Elsevier B.V., 2022-02-01) Lopes, Marta Marques de Carvalho; Rojas, Hugo Alberto; Polizzi, Luiza Franklin; Magalhaes, Kenia Cristina S. F.; Sandrim, Valeria Cristina [UNESP]; Dellaretti, Marcos; Rubatino, Fernando Victor Martins; Simoes, Renata Toscano; Fac Santa Casa BH FSCBH; Santa Casa Belo Horizonte Hosp; Universidade Estadual Paulista (UNESP); Univ Presidente Antonio Carlos
The mechanisms involved in aneurysmal etiology are complex and only partially understood. Genetic risk factors have already been related to the process of aneurysm rupture. Among the genetic factors, the T-786C and Glu298Asp polymorphisms of the eNOS gene have great clinical relevance, as they can affect the bioavailability of nitric oxide for the cerebrovascular system. Objective: To evaluate the relationship between eNOS T-786C and Glu298Asp polymorphisms and the aneurysm pathogenesis of patients seen in the Neurosurgery Department of Santa Casa de Belo Horizonte, as well as to compare them with sociodemographic characteristics and risk factors. Methods: A total of 211 whole blood samples were collected from patients with cerebral aneurysms, 160 with ruptured aneurysms, 51 with unruptured aneurysms and 215 controls. After DNA extraction, genotyping was performed using the PCR-RFLP technique. Allele and genotype frequencies were obtained using the GENEPOP 4.2 software, and statistical analysis was performed using the GraphPad Prism 5.0 program and RStudio version 1.4. Results: Age, female sex, smoking and small diameter of the aneurysms were associated with aneurysm development and rupture in the study population. The CC genotype of the T-786C polymorphism was associated with unruptured aneurysms with a diameter >12 mm. Conclusion: Age, female sex and smoking were associated with rupture. This study revealed that the CC mutant genotype of the eNOS gene T-786C polymorphism was associated with unruptured intracranial aneurysms larger than 12 mm in our study population, revealing a new association.
Effects of nandrolone decanoate and resistance exercise on skeletal muscle in adult male rats
(2012-01-01) Cruz, Cynthia Dela; Agati, Leandro B. [UNESP]; Pereira, Oduvaldo C.M. [UNESP]; Universidade Federal de Minas Gerais (UFMG); Universidade Estadual Paulista (UNESP)
The aim of this study was to compare the effects of resistance exercise associated or not with nandrolone decanoate (ND) on skeletal muscles and body mass of adult male rats. Training protocol consisted of 15 jump sessions, for 6 weeks. ND (5mg/kg) was administered twice a week. The exercise was effective in inducing respective enlargements in fiber areas of extensor digitorum longus and soleus muscles. ND associate with exercise was also able to induce increases in fiber areas these muscles. In untrained group that received nandrolone decanoate an improved in muscular parameters could be observed. In conclusion, the resistance exercise was able to promote an enlargement in fiber areas of both muscles studied without ND treatment, indicating that after a period of time of adaptation to exercise, the muscular effects caused by ND could be achieved in the same way by exercise, without ND and without risks for health.
Repercussions of adjuvant-induced arthritis on body composition, soleus muscle, and heart muscle of rats
(2020-01-01) Pita, L. M.; Spadella, M. A.; Montenote, M. C.; Oliveira, P. B.; Chies, A. B.; Faculdade de Medicina de Marília; Instituto de Biociências de Botucatu
This study investigated the repercussions of adjuvant-induced arthritis (AIA) on body composition and the structural organization of the soleus and cardiac muscles, including their vascularization, at different times of disease manifestation. Male rats were submitted to AIA induction by intradermal administration of 100 mL ofMycobacterium tuberculosis (50 mg/mL), in the right hind paw. Animals submitted to AIA were studied 4 (AIA4), 15 (AIA15), and 40 (AIA40) days after AIA induction as well as a control group of animals not submitted to AIA. Unlike the control animals, AIA animals did not gain body mass throughout the evolution of the disease. AIA reduced food consumption, but only on the 40th day after induction. In the soleus muscle, AIA reduced the wet mass in a time-dependent manner but increased the capillary density by the 15th day and the fiber density by both 15 and 40 days after induction. The diameter of the soleus fiber decreased from the 4th day after AIA induction as well as the capillary/fiber ratio, which was most evident on the 40th day. Moreover, AIA induced slight histopathological changes in the cardiac muscle that were more evident on the 15th day after induction. In conclusion, AIA-induced changes in body composition as well as in the soleus muscle fibers and vasculature have early onset but are more evident by the 15th day after induction. Moreover, the heart may be a target organ of AIA, although less sensitive than skeletal muscles.
Treatment with cyclic adenosine monophosphate modulators prior to in vitro maturation alters the lipid composition and transcript profile of bovine cumulus-oocyte complexes and blastocysts
(2018-01-01) Razza, Eduardo M.; Sudano, Mateus J.; Fontes, Patricia K.; Franchi, Fernanda F.; Belaz, Katia Roberta A.; Santos, Priscila H.; Castilho, Anthony C. S.; Rocha, Daniele F. O.; Eberlin, Marcos N.; Machado, Mariana F.; Nogueira, Marcelo F. G.; Nove de Julho University; Federal University of Pampa; Universidade de São Paulo (USP); Universidade Estadual de Campinas (UNICAMP); Km 572 - Bairro Limoeiro
Mammalian oocytes resume meiosis spontaneously after removal from the ovarian follicle. We tested the effects of a 2-h prematuration treatment (Pre-IVM) with forskolin (FSK) and 3-isobutyl-1-methylxanthine (IBMX) in bovine cumulus-oocyte complexes (COCs) on the lipid content of oocytes and blastocysts, on the membrane lipid composition of blastocysts and on the transcriptional profiling of cumulus cells and blastocysts in a high-throughput platform. Embryonic development rates to the morula (mean 56.1%) or blastocyst (mean 26.3%) stages were unaffected by treatment. Lipid content was not affected after Pre-IVM, but was increased after IVM in treated oocytes. Conversely, the lipid content was reduced in Pre-IVM blastocysts. Pre-IVM COCs generated blastocysts containing blastomeres with more unsaturated lipids in their membranes. Pre-IVM also altered the relative abundance of 31 gene transcripts after 2 h and 16 transcripts after 24 h in cumulus cells, while seven transcripts were altered in blastocysts. Our results suggest that the Pre-IVM treatment affected the lipid composition and transcriptional profiles of COCs and blastocysts. Therefore, Pre-IVM with FSK and IBMX could be used either to prevent spontaneous meiotic resumption during IVM or to modulate lipid composition in the membrane and cytoplasm of blastocysts, potentially improving bovine embryos.
In vitro production of bovine embryos: Cumulus/granulosa cell gene expression patterns point to early atresia as beneficial for oocyte competence
(2017-01-01) Mazzoni, Gianluca; Razza, Eduardo; Pedersen, Hanne S.; Secher, Jan; Kadarmideen, Haja N.; Callesen, Henrik; Stroebech, Lotte; Freude, Kristine; Hyttel, Poul; University of Copenhagen; Universidade de São Paulo (USP); Aarhus University; Technical University of Denmark; EmbryoTrans Biotech ApS
In vitro production (IVP) of bovine embryos has become widespread technology implemented in cattle breeding and production. Here, we review novel data on cumulus/granulosa cell gene expression, as determined by RNAseq on cellular material from pooled follicular fluids at the single animal level, and relate these finding to previous data on oocyte developmental competence and ultrastructure. The cumulus/granulosa cell gene expression patterns indicate that early follicular atresia is associated with increased blastocyst yield and this hypothesis is supported by previous data on oocyte competence and ultrastructure.
Influence of nitric oxide and phosphodiesterases during in vitro maturation of bovine oocytes on meiotic resumption and embryo production
(2017-06-01) Botigelli, Ramon Cesar; Schwarz, Katia Lancellotti; Zaffalon, Fabiane Gilli; Del Collado, Maite; Castro, Fernanda Cavallari; Fernandes, Hugo; Leal, Claudia Lima Verde; Universidade de São Paulo (USP); Universidade Do Estado de São Paulo
This study aimed to examine the effects of nitric oxide (NO) and different phosphodiesterase (PDE) families on meiosis resumption, nucleotides levels and embryo production. Experiment I, COCs were matured in vitro with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) associated or not with the soluble guanylate cyclase (sGC) inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), meiotic resumption and nucleotides levels were assessed. SNAP delayed germinal vesicle breakdown (GVBD) (53.4 ± 1.2 versus 78.4 ± 2.4% for controls, P < 0.05) and ODQ reversed its effect (73.4 ± 6.3%, P > 0.05). Cyclic GMP levels were higher in SNAP (3.94 ± 0.18, P < 0.05) and ODQ abolished the effect (2.48 ± 0.13 pmol/COC, P < 0.05), while cAMP levels were decreased in both treatments. Experiment II, COCs were cultured with SNAP alone or with PDEs inhibitors. SNAP alone or with PDEs inhibitors delayed GVBD (24.7 ± 2.8 to 56.9 ± 8.7%, P < 0.05) compared with the control (77.1 ± 1.8%), and SNAP and SNAP + cilostamide had lowest rates (34.9 ± 9.2% and 24.7 ± 2.8%). Experiment III, COCs were cultured (24-28 h) with SNAP and SNAP + cilostamide to assess metaphase II (MII) rates and embryo production. SNAP + cilostamide (50.0 ± 2.0%, P < 0.05) had lower MII rates at 24 h in vitro maturation (IVM), but at 28 h all groups were similar (66.6 to 71.4%, P > 0.05). Embryo development did not differ from the control for SNAP and cilostamide groups (38.7 ± 5.8, 37.9 ± 6.2 and 40.5 ± 5.8%, P > 0.05), but SNAP + cilostamide decreased embryo production (25.7 ± 6.9%, P < 0.05). In conclusion, SNAP was confirmed to delay meiosis resumption by the NO/sGC/cGMP pathway, by increasing cGMP, but not cAMP. Inhibiting different PDEs to further increase nucleotides in association with SNAP did not show any additive effects on meiosis resumption, indicating that other pathways are involved. Moreover, SNAP + cilostamide affected the meiosis progression and decreased embryo development.
Screening of biotechnical parameters for production of bovine inter-subspecies embryonic chimeras by the aggregation of tetraploid Bos indicus and diploid crossbred Bos taurus embryos
(2016-03-01) Razza, Eduardo M.; Satrapa, Rafael A.; Emanuelli, Isabele P.; Barros, Ciro M.; Nogueira, Marcelo F.G.; Universidade de São Paulo (USP); Distrito Industrial; Biotechnology Center of CESUMAR - University Center of Maringa
The aggregation of a tetraploid zebu embryo (Bos indicus, a thermotolerant breed) with a diploid taurine embryo (Bos taurus, a thermosensitive breed) should create a complete taurine fetus, whose extra-embryonic components, e.g., the chorion, is derived mainly from the zebu embryo. These zebu-derived extra-embryonic components may interact positively with the taurine embryo/fetus during pregnancy in a tropical environment. We tested different parameters for the production of tetraploid Nelore (Bos indicus) embryos to be combined via aggregation with crossbred Bos taurus (diploid) embryos in order to produce viable chimeric blastocysts. Bovine (Bos indicus or crossbred Bos taurus) embryos were produced in vitro according to standard procedures. Two-cell Bos indicus embryos were submitted to electrofusion with varying numbers of pulses (1 or 2), voltages (0.4, 0.5, 0.75, 1.0, 1.4 and 5.0 kV/cm) and time (20, 25, 50 and 60 μs) to produce tetraploid embryos. Electrofused embryos were cultured with crossbred non-fused embryos to form chimeras that developed until the blastocyst stage. The best fusion parameter was 0.75 kV/cm for 60 μs. Four chimeric blastocysts (tetraploid Nelore with diploid crossbred Holstein) were formed after 31 attempts in 4 replicates (13%). We established an optimal procedure for the production of tetraploid Bos indicus (4n) embryos and embryonic chimeras by aggregation of crossbred Bos taurus (2n) with Bos indicus (4n) embryos. This technique would be valid in applied research, by producing exclusively taurine calves, but with placental elements from the Bos indicus breed, following transfer of these chimeras into recipient cows.
Exercise increases the phenylephrine effects in isolated portal vein of trained rats
(2009-08-01) Chies, Agnaldo Bruno; de Souza Rossignoli, Patrícia; Faculty of Medicine of Marília; Biosciences Institute of Botucatu
Physical exercise evokes an extensive circulatory redistribution. However, the influence of exercise upon the effects of sympathomimetic agonists in veins was not well studied. Thus, the present study aimed to determine whether a single bout of exercise modifies the effects of sympathomimetic agonists in veins and whether this exercise-induced modification may be altered by exercise training. The results have shown that the training did not change the responsiveness of the rat portal vein, but exposure of trained animals to a single bout of exercise enhanced the phenylephrine Rmax in these preparations. Such exercise-induced modifications of vascular response were territory-specific since similar modifications of response to phenylephrine were not observed in vena cava. Moreover, this exercise-induced augmentation of phenylephrine Rmax in the portal vein of trained rats was prevented by endothelium removal or in the presence of Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), indomethacin, BQ-123 or BQ-788. In conclusion, these data indicate that the training adapted the rat portal vein to respond vigorously to sympathetic stimuli even when the animal is exposed to this exercise. This increased response to sympathetic stimuli appears to involve an enhancement of the vasocontractile influence of endothelin that supplants the modulation exerted by nitric oxide (NO) and vasodilator prostanoids. © 2009 Elsevier Inc. All rights reserved.
Pharmacological evidence that methylene blue inhibits noradrenaline neuronal uptake in the rat vas deferens
(2003-10-09) Chies, Agnaldo B.; Custódio, Ricardo C.; de Souza, Gregório; Corrêa, Fernando M.A.; Pereira, Oduvaldo C.M.; School of Medicine of Marília; School of Medicine of Ribeirao Preto; Biosciences Institute of Botucatu
We report that the classical guanylate cyclase inhibitor methylene blue (MB, 1 μM or 10 μM), but not the selective guanylate cyclase inhibitor 1H-[1,2,4]oxidazolo[4,3-a]quinoxalin-1-one (1 μM) or nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (100 μM), causes a shift to the left in the concentration-response curve for noradrenaline in the isolated rat vas deferens preparations. The main objective of our study was to investigate the pharmacological mechanism by which MB increases the sensitivity of the rat vas deferens to noradrenaline. According to the presented results, MB did not change rat vas deferens sensitivity to methoxamine or noradrenaline in the presence of desipramine (0.1 μM). The pre-contracted rat vas deferens relaxation induced by isoproterenol was also not significantly changed by MB (1 μM). Thus, we suggest that MB increases rat vas deferens sensitivity through neuronal uptake inhibition without interfering in either the nitrergic mechanism or guanylate cyclase activity.
Abortive and/or embryofetotoxic effect of Cinnamomum zeylanicum leaf extracts in pregnant rats
(1994-11-17) Pellegatti Lemonica, I.; Borro Macedo, A. M.R.; Institute of Biosciences
Female Wistar rats received by gavage 70 mg/kg of aqueous and chloroform extracts of C. zeylanicum during pregnancy. The results showed that the females treated with both the extracts presented an increased number of resorptions, which explains their use as an abortive infusion by Brazilian people. A non significant number of abnormalities was observed in live fetuses, the same occurring with fetal weight and number of dead fetuses.
Effects of methoxyflurane on intraocular and cerebrospinal fluid pressure in dogs with spontaneous or artificial respiration
(1979-12-01) Vassilieff, I.; De Oliveira Vassilieff, V. S.; Chagas, A. M.; Universidade Estadual Paulista (UNESP)
Methoxyflurane (0.2 ml/kg over 5 min), administered by inhalation to dogs with spontaneous respiration, resulted approximately 10 minutes later in a significant increase of intraocular pressure (IOP) (13.3 mm Hg), cerebrospinal fluid pressure (CSFP) (9.4 mm Hg), and venous pressure (VP) (6 mm Hg), as well as a significant decrease in arterial pressure (AP) (23.3 mm Hg), respiratory frequency (3.2 mov/min) and respiratory amplitude (7.1 mm). These alterations occurred concomitantly with respiratory acidosis, an increase in serum K+ and Cl-, increased osmolarity of the aqueous humor, and an elevation of K+ and Cl- in cerebrospinal fluid (CSF). However, if CSF was allowed to drain freely so that no increase of CSFP occurred, there was only a small increase of IOP (3.7 mm Hg). Under these latter conditions, there also was a decrease of arterial pressure (20.7 mm Hg), respiratory frequency (9.5 mov/min) and respiratory amplitude (2.1 mm). When dogs were ventilated artificially the above changes were greatly attenuated. They were limited to a small but significant rise of CSFP (4.7 mm Hg), a decrease in AP (20.7 mm Hg) and a decrease of HCO3- (7.6 mEq/) of arterial blood. The possible mechanisms involved in the action of methoxyflurane on IOP were discussed and it was pointed out that this anesthetic agent might be used for inducing anesthesia; however, it would be necessary to avoid respiratory depression, in order to prevent intracranial and ocular hypertension.
Generation of primordial germ cell-like cells from iPSCs derived from turner syndrome patients
(2021-11-01) Souza, Aline Fernanda de; Bressan, Fabiana Fernandes; Pieri, Naira Caroline Godoy; Botigelli, Ramon Cesar [UNESP]; Revay, Tamas; Haddad, Simone Kashima; Covas, Dimas Tadeu; Ramos, Ester Silveira; King, Willian Allan; Meirelles, Flavio Vieira; Universidade de São Paulo (USP); University of Guelph; Universidade Estadual Paulista (UNESP); University of Calgary
Turner syndrome (TS) is a genetic disorder in females with X Chromosome monosomy associated with highly variable clinical features, including premature primary gonadal failure leading to ovarian dysfunction and infertility. The mechanism of development of primordial germ cells (PGCs) and their connection with ovarian failure in TS is poorly understood. An in vitro model of PGCs from TS would be beneficial for investigating genetic and epigenetic factors that influence germ cell specification. Here we investigated the potential of reprogramming peripheral mononuclear blood cells from TS women (PBMCs-TS) into iPSCs following in vitro differentiation in hPGCLCs. All hiPSCs-TS lines demonstrated pluripotency state and were capable of differentiation into three embryonic layers (ectoderm, endoderm, and mesoderm). The PGCLCs-TS recapitulated the initial germline development period regarding transcripts and protein marks, including the epigenetic profile. Overall, our results highlighted the feasibility of producing in vitro models to help the understanding of the mechanisms associated with germ cell formation in TS.
Desenvolvimento de um método analítico rápido e eficiente para a determinação de corticosteroídes plasmáticos por injeção direta em coluna cromatográfica ISRP-C18 por CLAE
(2010-01-01) Toledo-Pinto, E. A. [UNESP]; Menezes, M. L. [UNESP]; Pereira, O. C.M. [UNESP]; Universidade Estadual Paulista (UNESP)
The present work had as aim the development of simple an analytical method, fast efficient and the determination of corticosteroids (cortisone, corticosterone, acetate of hidrocortisone and acetate of dexametasone) in sanguine samples of rats using an isocratic system of liquid chromatography of high efficiency (CLAE) with ultraviolet detention. The method involved direct injection of sanguine sample in a chromatographic column with internal surface of phase reverse (ISRP-C18), using the composed mobile phase for drain plug phosphate pH 4,0: acetonitrile (65:35 v/v). The detention the analytes was obtained using an ultraviolet detector of changeable wave length (Varian Model 2550) adjusted in 240 nm and a 4400 integrator SP Chromaject (Varian Associates, Inc., Sunnyvale, CA, USA). The extraction of the analyte resulted in recovery values between 90% and 108%, and variation coefficient enter 1,1% and 2.5%. The detention and quantification limits of the method were 0,02 and 0,04 μg mL-1, respectively. In conclusion, the analytical method possible the direct injection (on-line) of the sample without previous treatment also presenting some advantages, such as: fast, exactness, precision and specific.
Cattle in vitro induced pluripotent stem cells generated and maintained in 5 or 20% oxygen and different supplementation
(2021-06-01) Bessi, Brendon Willian; Botigelli, Ramon Cesar [UNESP]; Pieri, Naira Caroline Godoy; Machado, Lucas Simões; Cruz, Jessica Brunhara; de Moraes, Pamela; de Souza, Aline Fernanda; Recchia, Kaiana; Barbosa, Gabriela; de Castro, Raquel Vasconcelos Guimarães [UNESP]; Nogueira, Marcelo Fábio Gouveia [UNESP]; Bressan, Fabiana Fernandes; Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP)
The event of cellular reprogramming into pluripotency is influenced by several factors, such as in vitro culture conditions (e.g., culture medium and oxygen concentration). Herein, bovine iPSCs (biPSCs) were generated in different levels of oxygen tension (5% or 20% of oxygen) and supple-mentation (bFGF or bFGF + LIF + 2i—bFL2i) to evaluate the efficiency of pluripotency induction and maintenance in vitro. Initial reprogramming was observed in all groups and bFL2i supplementation initially resulted in a superior number of colonies. However, bFL2i supplementation in low oxygen led to a loss of self-renewal and pluripotency maintenance. All clonal lines were positive for alkaline phosphatase; they expressed endogenous pluripotency-related genes SOX2, OCT4 and STELLA. However, expression was decreased throughout the passages without the influence of oxygen tension. GLUT1 and GLUT3 were upregulated by low oxygen. The biPSCs were immunofluorescence-positive stained for OCT4 and SOX2 and they formed embryoid bodies which differentiated in ectoderm and mesoderm (all groups), as well as endoderm (one line from bFL2i in high oxygen). Our study is the first to compare high and low oxygen environments during and after induced reprogramming in cattle. In our conditions, a low oxygen environment did not favor the pluripotency maintenance of biPSCs.

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