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- Abnormal immunoreactivity to serotonin in cerebellar purkinje cells after neonatal cocaine exposurePublication . Summavielle, Teresa; Alves, Cecília J.; Monteiro, Pedro; Tavares, Maria AméliaNeonatal cocaine is known to affect the developing serotonergic system in many brain structures, including the cerebellum. Changes in the cerebellar Purkinje cells after drug exposure are well documented and result in impairment of movement and other cerebellar disorders such as ataxia. These cells have a major postnatal developmental pattern; therefore, neonatal exposure to cocaine is likely to affect them. In this work, male and female Wistar rats were injected with 15 mg of cocaine hydrochloride/kg body weight/day, subcutaneously, in two daily doses, from postnatal day 1 (PND1) to PND29. Controls were given 0.9% of saline. On PND14, PND21, and PND30, rats were transcardially perfused, and brains removed and cryoprotected. Coronal sections from the cerebellum were processed for immunocytochemistry of cells containing serotonin (5-hydroxytryptamine, or 5-HT). At the same postnatal age, rats from at least three different litters were sacrificed by decapitation, and brains were dissected for determination of 5-HT in the cerebellum by high-performance liquid chromatography with electrochemical detection. Upon the expected distribution of immunoreactivity to 5-HT, an abnormal immunoreactivity to 5-HT was observed in the Purkinje cells of six cocaineexposed animals, but not in control animals. Also, levels of cerebellar 5-HT in cocaine-exposed rats were significantly increased on PND21. These results, together with previously reported observations of altered patterns of motor behavior, indicate that neonatal cocaine exposure affects the serotonergic cerebellar system, altering the standard development of Purkinje cells and possibly compromising the motor function.
- Acetil-L-Carnitina como neuroprotetor na excitotoxicidade do glutamatoPublication . Casais, Joana; Lobo, Andrea; Summavielle, TeresaA excitotoxicidade consiste na ativação excessiva de recetores de glutamato, causada pela acumulação extracelular deste neurotransmissor. A ativação dos recetores de glutamato promove o aumento excessivo da concentração intracelular de cálcio e morte neuronal associada à ativação de protéases como calpaínas e caspases - acontecimentos típicos de patologias como isquémia cerebral, Alzheimer, Parkinson e Huntington. A acetil-L-carnitina (ALC) é um éster da L-carnitina com funções neuroprotetoras, mas o mecanismo envolvido permanece desconhecido.
- Acetyl-L-Carnitine prevents methamphetamine-induced structural damage on endothelial cells via ILK-related MMP-9 activityPublication . Summavielle, Teresa; Fernandes, S.; Salta, S.; Bravo, J.; Silva, A.P.Methamphetamine (METH) is a potent psychostimulant highly used worldwide. Recent studies evidenced the involvement of METH in the breakdown of the blood-brain-barrier (BBB) integrity leading to compromised function. The involvement of the matrix metalloproteinases (MMPs) in the degradation of the neurovascular matrix components and tight junctions (TJs) is one of the most recent findings in METH-induced toxicity. As BBB dysfunction is a pathological feature of many neurological conditions, unveiling new protective agents in this field is of major relevance. Acetyl- L-carnitine (ALC) has been described to protect the BBB function in different paradigms, but the mechanisms underlying its action remain mostly unknown. Here, the immortalized bEnd.3 cell line was used to evaluate the neuroprotective features of ALC in METH-induced damage. Cells were exposed to ranging concentrations of METH, and the protective effect of ALC 1 mM was assessed 24 h after treatment. F-actin rearrangement, TJ expression and distribution, and MMPs activity were evaluated. Integrin-linked kinase (ILK) knockdown cells were used to assess role of ALC in ILK mediated METH-triggered MMPs’ activity. Our results show that METH led to disruption of the actin filaments concomitant with claudin-5 translocation to the cytoplasm. These events were mediated by MMP-9 activation in association with ILK overexpression. Pretreatment with ALC prevented METH-induced activation of MMP-9, preserving claudin-5 location and the structural arrangement of the actin filaments. The present results support the potential of ALC in preserving BBB integrity, highlighting ILK as a new target for the ALC therapeutic use.
- Acute effect of neuromuscular electrostimulation in the torque and cross-sectional area of the Extensor Digitorum Communis muscle. Real-time ultrasound imagingPublication . Lopes, Alexandre; Faria, Susana; Quadrado, Pedro; Silva, Diogo C. F.Neuromuscular electrostimulation (NMES) is a therapeutic resource widely used by most physiotherapists with the objective of favoring muscle strengthening, prevention or recovery from atrophy due to disuse, however there is still no scientific consensus on which is the most effective current for this purpose. This study aims to evaluate the acute effect induced by low and medium frequency electrostimulation in an isometric contraction of wrist extension and compare them with the maximum voluntary isometric contraction (MVIC) (1) in the force production capacity and (2) in the vertical and horizontal values of the cross-sectional area of the Extensor Digitorum Communis muscle (EDC). There are no differences between the mean values for height or width between the TENS and Kotz currents, nor between the two NMES currents and the MVIC. No differences were found in the capacity for power generation of the administration of NMES currents and the MVIC. No differences were found in the height or width values between the TENS and Kotz currents, nor between the two NMES currents and the MVIC. No differences were found in the capacity for power generation of the exclusive administration of NMES currents and the MVIC, in a population of healthy adults.
- Acute effects of physical exercise with microcurrent in the adipose tissue of the abdominal region: A randomized controlled trialPublication . Noites, Andreia; Moreira, Anabela; Melo, Cristina; Faria, Miriam; Vilarinho, Rui; Freitas, Carla; Monteiro, Pedro; Carvalho, Paulo; Adubeiro, Nuno; Sousa, Maria; Santos, Rubim; Nogueira, LuisaIncreased abdominal fat and sedentary lifestyles contribute to cardiovascular disease risk. Low-intensity electrical current (microcurrent) on the abdominal region, associated with physical exercise, appears to be an innovative method to increase the lipolytic rate of abdominal adipocytes, in order to reduce abdominal fat. This study aimed to analyze the acute effects of microcurrent associated with an aerobic exercise program in healthy subjects in lipolysis. A double-blinded, randomized controlled trial was developed and conducted in a higher education school. Eighty-three healthy subjects, aged between 18 and 30 years old and with a 18.5 to 29.9 kg/m2 body mass index were randomly assigned either to an experimental or to a placebo group. Subjects received a trans-abdominal microcurrent stimulation for 40 min with (experimental group) or without (placebo group) electrical current, followed by a single aerobic exercise session (60 min at 45–55% VO2max intensity). Lipolytic activity (serum glycerol), abdominal fat (waist circumference, abdominal skinfold, ultrasonography), and serum lipid profile (serum triglyceride, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol) were evaluated in all subjects. Physical activity (International Physical Activity Questionnaire) and dietary intake (food-frequency questionnaire) questionnaires were applied. After the intervention, lipolytic rate was significantly higher (p = 0.003) in the experimental group (mean = 0.15) than in the placebo group (mean = 0.09). Glycerol results showed a statistically significant increase between baseline and after the intervention for both experimental group (p = 0.001) and the placebo group (p = 0.001). Combined use of microcurrent and physical aerobic exercise had an acute effect enhancing lipolytic rate comparing to exercise alone, in young healthy subjects.
- Addressing the role of maternal age on the metabolic profile of the placentaPublication . Pinheiro, Ana R.; Rodrigues, Adriana; Matos, Liliana; Guedes-Martins, Luís; Almeida, Henrique; Silva, ElisabeteAfter the age of 35, during pregnancy, there is an increased risk of impaired placentation. Changes in uterine redox balance seem to play a role in deficient placentation. We hypothesized that this local redox dysregulation has a negative impact on the placenta metabolic profile. Thus, we aimed to study the placenta metabolic profile during reproductive aging and the effect of antioxidant supplementation. Placentas were collected from pregnant women aged between 22 and 41 years, and from mice of different ages (3 or 9 months). Additionally, 9-month-old mice were treated with apocynin (5 mM) in the drinking water (3 weeks prior to and during pregnancy). Semi-quantitative real-time PCR was carried out to assess the expression of glucose and fatty acid transporters. Quantitative results are presented with standard error of the mean (SEM). In the human study, Spearman’s correlation was used for the comparative analysis of the variables studied. In the animal model, Student’s t-test was used for comparative analysis of the variables studied. A p-value of less than 0.05 was considered statistically significant. Concerning glucose transport, the results show that the expression of glucose transporter 1 is strongly negatively correlated with maternal age (r = 0.710; p = 0.0121). Regarding lipid metabolism, there is a strong negative correlation between the fatty acid transporter 4 expression and maternal age (r = -0.6865, p = 0.0233). In mice, the expression of glucose transporter 1 was also decreased in 9-month-old females (p = 0.0329, when compared to the 3-month-old females group). No differences were observed between the reproductively aged females treated with apocynin and the young females (p = 0.1990). The results of this study show that reproductive aging is linked with changes in the placenta metabolic profile. In the mice study model, antioxidant supplementation attenuated the changes observed in nutrient transport in the placenta.
- Alendronic Acid as Ionic Liquid: New Perspective on OsteosarcomaPublication . Teixeira, Sónia; Santos, Miguel M.; Fernandes, Maria H.; Costa-Rodrigues, Joao; Branco, Luís C.Herein the quantitative synthesis of eight new mono- and dianionic Organic Salts and Ionic Liquids (OSILs) from alendronic acid (ALN) is reported by following two distinct sustainable and straightforward methodologies, according to the type of cation. The prepared ALN-OSILs were characterized by spectroscopic techniques and their solubility in water and biological fluids was determined. An evaluation of the toxicity towards human healthy cells and also human breast, lung and bone (osteosarcoma) cell lines was performed. Globally, it was observed that the monoanionic OSILs showed lower toxicity than the corresponding dianionic structures to all cell types. The highest cytotoxic effect was observed in OSILs containing a [C2OHMIM] cation, in particular [C2OHMIM][ALN]. The latter showed an improvement in IC50 values of ca. three orders of magnitude for the lung and bone cancer cell lines as well as fibroblasts in comparison with ALN. The development of OSILs with high cytotoxicity effect towards the tested cancer cell types, and containing an anti-resorbing molecule such as ALN may represent a promising strategy for the development of new pharmacological tools to be used in those pathological conditions.
- Alterações imediatas induzidas pela electroestimulação neuromuscular de baixa e média frequência no torque e na área de secção transversal do músculo reto femoral, em adultos saudáveisPublication . Lopes, Alexandre; Silva, Diogo C. F.; Torres, Rui; Carvalho, PauloA electroestimulação neuromuscular (NMES) é um recurso terapêutico amplamente utilizado pela maioria dos fisioterapeutas com o objetivo de favorecer o fortalecimento muscular, a prevenção ou a recuperação, no entanto, ainda sem consenso científico.
- Altered environmental perception by parental stress and depression vulnerability: impact on mothers and offspringPublication . Alves, Renata L.; Portugal, Camila C.; Lopes, Igor M.; Oliveira, Pedro; Alves, Cecília J.; Barbosa, Fernando; Summavielle, Teresa; Magalhães, Ana; Summavielle, TeresaDepressive mothers often find the mother-child interaction to be challenging. Parental stress may further impair mother-child attachment, which may increase the risk of negative developmental consequences. We used rats with different vulnerability to depression (Wistar and Kyoto) to investigate the impact of stress (maternal separationMS) on maternal behaviour and adolescent offspring cognition. MS in Kyoto dams increased pup-contact, resulting in higher oxytocin levels and lower anxiety-like behaviour after weaning, while worsening their adolescent offspring cognitive behaviour. Whereas MS in Wistar dams elicited higher quality of pup-directed behaviour, increasing Brain-Derived Neurotrophic Factor (BDNF) in the offspring, which seems to have prevented a negative impact on cognition. Hypothalamic oxytocin seems to impact the salience of the social environment cues (as negative for Kyoto) leading to different coping strategies. Our findings highlight the importance of contextual and individual factors in the understanding of the oxytocin role in modulating maternal behaviour and stress regulatory processes.
- Antiproliferative organic salts derived from betulinic acid: Disclosure of an ionic liquid selective against lung and liver cancer cellsPublication . Silva, Ana Teresa; Cerqueira, Maria João; Prudêncio, Cristina; Fernandes, Maria Helena; Costa-Rodrigues, João; Teixeira, Cátia; Gomes, Paula; Ferraz, RicardoIn the last few years, we have been witnessing an increasing interest in ionic liquids (ILs) and organic salts, given their potential applications in biological and pharmaceutical sciences. We report the synthesis and in vitro evaluation of novel organic salts combining betulinate, known for its anticancer properties, with antimalarial drugs, primaquine, chloroquine, and mepacrine, and also with the trihexyltetradecylphosphonium ([P6,6,6,14]) cation. The salts were screened for their in vitro activity against tumor lines HepG2 (liver), MG63 (osteosarcoma), T47D (breast), A459 (lung), and RKO (colon), and also on normal human fibroblasts. All betulinates prepared displayed antiproliferative properties, with the trihexyltetradecylphosphonium betulinate standing out for its higher selectivity. This unprecedented disclosure of a betulinic acid (BA)-derived IL with selective antitumor activity constitutes a relevant first step toward development of novel anticancer therapies based on BA-derived IL.