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1.
J Neurosci ; 44(14)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38467434

RESUMO

Alterations in γ-aminobutyric acid (GABA) have been implicated in sensory differences in individuals with autism spectrum disorder (ASD). Visual signals are initially processed in the retina, and in this study, we explored the hypotheses that the GABA-dependent retinal response to light is altered in individuals with ASD. Light-adapted electroretinograms were recorded from 61 adults (38 males and 23 females; n = 22 ASD) in response to three stimulus protocols: (1) the standard white flash, (2) the standard 30 Hz flickering protocol, and (3) the photopic negative response protocol. Participants were administered an oral dose of placebo, 15 or 30 mg of arbaclofen (STX209, GABAB agonist) in a randomized, double-blind, crossover order before the test. At baseline (placebo), the a-wave amplitudes in response to single white flashes were more prominent in ASD, relative to typically developed (TD) participants. Arbaclofen was associated with a decrease in the a-wave amplitude in ASD, but an increase in TD, eliminating the group difference observed at baseline. The extent of this arbaclofen-elicited shift significantly correlated with the arbaclofen-elicited shift in cortical responses to auditory stimuli as measured by using an electroencephalogram in our prior study and with broader autistic traits measured with the autism quotient across the whole cohort. Hence, GABA-dependent differences in retinal light processing in ASD appear to be an accessible component of a wider autistic difference in the central processing of sensory information, which may be upstream of more complex autistic phenotypes.


Assuntos
Transtorno do Espectro Autista , Masculino , Adulto , Feminino , Humanos , Transtorno do Espectro Autista/tratamento farmacológico , Retina , Eletroencefalografia , Ácido gama-Aminobutírico , Eletrorretinografia
2.
Mol Psychiatry ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326560

RESUMO

Men with antisocial personality disorder (ASPD) with or without psychopathy (+/-P) are responsible for most violent crime in society. Development of effective treatments is hindered by poor understanding of the neurochemical underpinnings of the condition. Men with ASPD with and without psychopathy demonstrate impulsive decision-making, associated with striatal abnormalities in functional neuroimaging studies. However, to date, no study has directly examined the potential neurochemical underpinnings of such abnormalities. We therefore investigated striatal glutamate: GABA ratio using Magnetic Resonance Spectroscopy in 30 violent offenders (16 ASPD-P, 14 ASPD + P) and 21 healthy non-offenders. Men with ASPD +/- P had a significant reduction in striatal glutamate : GABA ratio compared to non-offenders. We report, for the first time, striatal Glutamate/GABA dysregulation in ASPD +/- P, and discuss how this may be related to core behavioral abnormalities in the disorders.

3.
Int J Mol Sci ; 24(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36982836

RESUMO

Psidium guajava L. (guava) leaves have demonstrated their in vitro and in vivo effect against diabetes mellitus (DM). However, there is a lack of literature concerning the effect of the individual phenolic compounds present in the leaves in DM disease. The aim of the present work was to identify the individual compounds in Spanish guava leaves and their potential contribution to the observed anti-diabetic effect. Seventy-three phenolic compounds were identified from an 80% ethanol extract of guava leaves by high performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry. The potential anti-diabetic activity of each compound was evaluated with the DIA-DB web server that uses a docking and molecular shape similarity approach. The DIA-DB web server revealed that aldose reductase was the target protein with heterogeneous affinity for compounds naringenin, avicularin, guaijaverin, quercetin, ellagic acid, morin, catechin and guavinoside C. Naringenin exhibited the highest number of interactions with target proteins dipeptidyl peptidase-4, hydroxysteroid 11-beta dehydrogenase 1, aldose reductase and peroxisome proliferator-activated receptor. Compounds catechin, quercetin and naringenin displayed similarities with the known antidiabetic drug tolrestat. In conclusion, the computational workflow showed that guava leaves contain several compounds acting in the DM mechanism by interacting with specific DM protein targets.


Assuntos
Catequina , Diabetes Mellitus , Psidium , Humanos , Aldeído Redutase , Diabetes Mellitus/tratamento farmacológico , Extratos Vegetais/química , Folhas de Planta/química , Psidium/química , Quercetina/análise
4.
Int J Mol Sci ; 23(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408993

RESUMO

The brain is one of the most energy-consuming organs in the mammalian body, and synaptic transmission is one of the major contributors. To meet these energetic requirements, the brain primarily uses glucose, which can be metabolized through glycolysis and/or mitochondrial oxidative phosphorylation. The relevance of these two energy production pathways in fulfilling energy at presynaptic terminals has been the subject of recent studies. In this review, we dissect the balance of glycolysis and oxidative phosphorylation to meet synaptic energy demands in both resting and stimulation conditions. Besides ATP output needs, mitochondria at synapse are also important for calcium buffering and regulation of reactive oxygen species. These two mitochondrial-associated pathways, once hampered, impact negatively on neuronal homeostasis and synaptic activity. Therefore, as mitochondria assume a critical role in synaptic homeostasis, it is becoming evident that the synaptic mitochondria population possesses a distinct functional fingerprint compared to other brain mitochondria. Ultimately, dysregulation of synaptic bioenergetics through glycolytic and mitochondrial dysfunctions is increasingly implicated in neurodegenerative disorders, as one of the first hallmarks in several of these diseases are synaptic energy deficits, followed by synapse degeneration.


Assuntos
Sinapses , Transmissão Sináptica , Animais , Encéfalo/metabolismo , Metabolismo Energético/fisiologia , Mamíferos , Terminações Pré-Sinápticas/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
5.
Int J Mol Sci ; 23(4)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35216431

RESUMO

Blood-contacting devices are increasingly important for the management of cardiovascular diseases. Poly(ethylene glycol) (PEG) hydrogels represent one of the most explored hydrogels to date. However, they are mechanically weak, which prevents their use in load-bearing biomedical applications (e.g., vascular grafts, cardiac valves). Graphene and its derivatives, which have outstanding mechanical properties, a very high specific surface area, and good compatibility with many polymer matrices, are promising candidates to solve this challenge. In this work, we propose the use of graphene-based materials as nanofillers for mechanical reinforcement of PEG hydrogels, and we obtain composites that are stiffer and stronger than, and as anti-adhesive as, neat PEG hydrogels. Results show that single-layer and few-layer graphene oxide can strengthen PEG hydrogels, increasing their stiffness up to 6-fold and their strength 14-fold upon incorporation of 4% w/v (40 mg/mL) graphene oxide. The composites are cytocompatible and remain anti-adhesive towards endothelial cells, human platelets and Staphylococcus aureus, similar to neat hydrogels. To the best of our knowledge, this is the first work to report such an increase of the tensile properties of PEG hydrogels using graphene-based materials as fillers. This work paves the way for the exploitation of PEG hydrogels as a backbone material for load-bearing applications.


Assuntos
Grafite/química , Hidrogéis/química , Polietilenoglicóis/química , Adesivos/química , Materiais Biocompatíveis/química , Linhagem Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Polímeros/química , Engenharia Tecidual/métodos
6.
Proc Biol Sci ; 288(1954): 20211156, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34229495

RESUMO

Animals use varied acoustic signals that play critical roles in their lives. Understanding the function of these signals may inform about key life-history processes relevant for conservation. In the case of fin whales (Balaenoptera physalus), that produce different call types associated with different behaviours, several hypotheses have emerged regarding call function, but the topic still remains in its infancy. Here, we investigate the potential function of two fin whale vocalizations, the song-forming 20-Hz call and the 40-Hz call, by examining their production in relation to season, year and prey biomass. Our results showed that the production of 20-Hz calls was strongly influenced by season, with a clear peak during the breeding months, and secondarily by year, likely due to changes in whale abundance. These results support the reproductive function of the 20-Hz song used as an acoustic display. Conversely, season and year had no effect on variation in 40-Hz calling rates, but prey biomass did. This is the first study linking 40-Hz call activity to prey biomass, supporting the previously suggested food-associated function of this call. Understanding the functions of animal signals can help identifying functional habitats and predict the negative effects of human activities with important implications for conservation.


Assuntos
Baleia Comum , Acústica , Animais , Biomassa , Vocalização Animal , Baleias
7.
BMC Health Serv Res ; 21(1): 756, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330280

RESUMO

BACKGROUND: The implementation of a population-based screening programme for diabetic retinopathy involves several challenges, often leading to postponements and setbacks at high human and material costs. Thus, it is of the utmost importance to promote the sharing of experiences, successes, and difficulties. However, factors such as the existence of regional programmes, specificities of each country's health systems, organisational and even linguistic barriers, make it difficult to create a solid framework that can be used as a basis for future projects. METHODS: Web of Science and PubMed platforms were searched using appropriate key words. The review process resulted in 423 articles adherent to the search criteria, 28 of which were accepted and analysed. Web sites of all Portuguese governmental and non-governmental organisations, with a relevant role on the research topic, were inspected and 75 official documents were retrieved and analysed. RESULTS: Since 2001, five regional screening programmes were gradually implemented under the guidelines of Portuguese General Health Department. However, complete population coverage was still not achieved. Among the main difficulties reported are the complex articulation between different levels of care providers, the low number of orthoptic technician in the national health system, the high burden that images grading, and treatment of positive cases represents for hospitals ophthalmology services, and low adherence rates. Yet, the comparison between strategies adopted in the different regions allowed the identification of potential solutions: hire orthoptic technician for primary health care units, eliminating the dependence of hospital professionals; use artificial intelligence algorithms for automatic retinographies grading, avoiding ophthalmologists overload; adoption of proximity strategies, as the use of portable retinographers, to promote adherence to screening. CONCLUSION: Access to diabetic retinopathy screening remains remarkably variable in Portugal and needs urgent attention. However, several characteristics of effective screening programmes were found in Portuguese screening programmes, what seems to point toward promising outcomes, especially if each other highlights are considered. The findings of this research could be very useful for the other countries with similar socio-political characteristics. TRIAL REGISTRATION: PROSPERO registration ID CRD42020200115 .


Assuntos
Inteligência Artificial , Retinopatia Diabética , Retinopatia Diabética/diagnóstico , Humanos , Programas de Rastreamento , Portugal
8.
Genet Mol Biol ; 44(2): e20200448, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34137427

RESUMO

The inclusion of a genetic risk score (GRS) can modify the risk prediction of coronary artery disease (CAD), providing an advantage over the use of traditional models. The predictive value of the genetic information on the recurrence of major adverse cardiovascular events (MACE) remains controversial. A total of 33 genetic variants previously associated with CAD were genotyped in 1587 CAD patients from the GENEMACOR study. Of these, 18 variants presented an hazard ratio >1, so they were selected to construct a weighted GRS (wGRS). MACE discrimination and reclassification were evaluated by C-Statistic, Net Reclassification Index and Integrated Discrimination Improvement methodologies. After the addition of wGRS to traditional predictors, the C-index increased from 0.566 to 0.572 (p=0.0003). Subsequently, adding wGRS to traditional plus clinical risk factors, this model slightly improved from 0.620 to 0.622 but with statistical significance (p=0.004). NRI showed that 17.9% of the cohort was better reclassified when the primary model was associated with wGRS. The Kaplan-Meier estimator showed that, at 15-year follow-up, the group with a higher number of risk alleles had a significantly higher MACE occurrence (p=0.011). In CAD patients, wGRS improved MACE risk prediction, discrimination and reclassification over the conventional factors, providing better cost-effective therapeutic strategies.

9.
J Sport Rehabil ; 30(7): 1060-1066, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034229

RESUMO

CONTEXT: Neural mobilization is commonly used in sports, and previous studies have suggested that it has a positive impact on lower-limb flexibility and performance. However, studies exploring the effect of neural mobilization dosage are almost nonexistent. OBJECTIVES: This study aimed to assess whether 2 distinct dosages of neural gliding mobilization (4 and 8 sets of 10 repetitions) impact the flexibility and performance of both the mobilized and nonmobilized lower limb in basketball athletes differently. DESIGN: Randomized, parallel, and single-blinded study. SETTING: Amateur and professional basketball clubs. PARTICIPANTS: Fifty-two basketball athletes (40 men and 12 women), who were distributed into 2 groups; one received 40 (n = 28) and the other 80 repetitions (n = 24) of neural gliding mobilization. INTERVENTION: Neural gliding mobilization applied to a single limb (the dominant limb). MAIN OUTCOME MEASURES: Knee extension angle for hamstring flexibility; hop tests and single-leg vertical jump for performance. RESULTS: There was a significant main effect of time (P < .001), a significant interaction between time and limb for flexibility (P = .003), and a significant interaction between time and limb for the single-leg hop test (P = .032). No other significant main effect for any of the remaining variables was found (P > .05). CONCLUSIONS: The application of both 40 repetitions and 80 of neural gliding significantly improved lower-limb flexibility, and one was not superior to the other. Neither one dosage nor the other positively or negatively impacted the lower-limb performance of basketball athletes.


Assuntos
Basquetebol , Atletas , Feminino , Humanos , Articulação do Joelho , Extremidade Inferior , Masculino
10.
J Anat ; 236(5): 840-853, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31997379

RESUMO

Intrauterine growth restriction (IUGR) is a serious condition which impairs the achievement of the fetus' full growth potential and occurs in a natural and severe manner in pigs as a result of placental insufficiency. Reduced skeletal muscle mass in the fetus with IUGR persists into adulthood and may contribute to increased metabolic disease risk. To investigate skeletal muscle postnatal development, histomorphometrical patterns of the semitendinosus muscle, myosin heavy chain (MyHC; embryonic I, IIA, IIB and IIX isoforms) fiber composition and the relative expression of genes related to myogenesis, adipogenesis and growth during three specific periods: postnatal myogenesis (newborn to 100 days old), hypertrophy (100-150 days old), and postnatal development (newborn to 150 days old) were evaluated in female pigs with IUGR and normal birth weight (NW) female littermates. NW females presented higher body weights compared to their IUGR counterparts at all ages evaluated (P < 0.05). Moreover, growth restriction in utero affected the semitendinosus muscle weight, muscle fiber diameter, and muscle cross-sectional area, which were smaller in IUGR pigs at birth (P < 0.05). Notwithstanding the effects on muscle morphology, IUGR also affected muscle fiber composition, as the percentage of MyHC-I myofibers was higher at birth (P < 0.05), and, in 150-day-old gilts, a lower percentage of MyHC-IIX isoform (P < 0.05) and the presence of embryonic MyHC isoform were also observed. Regarding the pattern of gene expression in both the postnatal myogenesis and postnatal development periods, IUGR led to the downregulation of myogenic factors, which delayed skeletal muscle myogenesis (PAX7, MYOD, MYOG, MYF5 and DES). Altogether, growth restriction in utero affects muscle fiber number and size at birth and muscle fiber composition through the downregulation of myogenic factors, which determines the individual´s postnatal growth rate. This fact, associated with delayed myofiber development in growth-restricted animals, may affect meat quality characteristics in animal production. Hence, knowledge of the morphofunctional phenotype of the skeletal muscle throughout postnatal development in individuals with IUGR, and the mechanism that governs it, may provide a better understanding of the mechanisms that limit postnatal muscle growth, and help the establishment of potential strategies to improve muscle development and prevent the onset of later-life metabolic diseases.


Assuntos
Retardo do Crescimento Fetal/fisiopatologia , Desenvolvimento Muscular/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Animais , Feminino , Retardo do Crescimento Fetal/metabolismo , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Cadeias Pesadas de Miosina/metabolismo , Fenótipo , Gravidez , Sus scrofa , Suínos
11.
J Chem Inf Model ; 60(9): 4124-4130, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32692571

RESUMO

The DIA-DB is a web server for the prediction of diabetes drugs that uses two different and complementary approaches: (a) comparison by shape similarity against a curated database of approved antidiabetic drugs and experimental small molecules and (b) inverse virtual screening of the input molecules chosen by the users against a set of therapeutic protein targets identified as key elements in diabetes. As a proof of concept DIA-DB was successfully applied in an integral workflow for the identification of the antidiabetic chemical profile in a complex crude plant extract. To this end, we conducted the extraction and LC-MS based chemical profile analysis of Sclerocarya birrea and subsequently utilized this data as input for our server. The server is open to all users, registration is not necessary, and a detailed report with the results of the prediction is sent to the user by email once calculations are completed. This is a novel public domain database and web server specific for diabetes drugs and can be accessed online through http://bio-hpc.eu/software/dia-db/.


Assuntos
Diabetes Mellitus , Preparações Farmacêuticas , Computadores , Bases de Dados Factuais , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes , Internet , Software
12.
J Mater Sci Mater Med ; 31(8): 69, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32705408

RESUMO

In recent years, the engineering of biomimetic cellular microenvironments has emerged as a top priority for regenerative medicine, being the in vitro recreation of the arcade-like cartilaginous tissue one of the most critical challenges due to the notorious absence of cost- and time-efficient microfabrication techniques capable of building 3D fibrous scaffolds with precise anisotropic properties. Taking this into account, we suggest a feasible and accurate methodology that uses a sequential adaptation of an electrospinning-electrospraying set up to construct a hierarchical system comprising both polycaprolactone (PCL) fibres and polyethylene glycol sacrificial microparticles. After porogen leaching, the bi-layered PCL scaffold was capable of presenting not only a depth-dependent fibre orientation similar to natural cartilage, but also mechanical features and porosity proficient to encourage an enhanced cell response. In fact, cell viability studies confirmed the biocompatibility of the scaffold and its ability to guarantee suitable cell adhesion, proliferation and migration throughout the 3D anisotropic fibrous network during 21 days of culture. Additionally, likewise the hierarchical relationship between chondrocytes and their extracellular matrix, the reported PCL scaffold was able to induce depth-dependent cell-material interactions responsible for promoting a spatial modulation of the morphology, alignment and density of the cells in vitro.


Assuntos
Cartilagem/citologia , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Biomimética , Cartilagem/efeitos dos fármacos , Cartilagem/fisiologia , Bovinos , Sobrevivência Celular , Células Cultivadas , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrócitos/fisiologia , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Galvanoplastia/métodos , Matriz Extracelular/química , Matriz Extracelular/efeitos dos fármacos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Microtecnologia/métodos , Poliésteres/química , Poliésteres/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Medicina Regenerativa/instrumentação , Medicina Regenerativa/métodos , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
13.
J Acoust Soc Am ; 148(5): 3086, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33261404

RESUMO

The interference between the direct path and the sea surface reflection of a signal as measured by a receiver is called Lloyd's Mirror effect (LME). It results in a frequency-dependent interference pattern that can be observed in a spectrogram. LME depends on the receiver depth, signal source depth, signal frequency, and slant range between source and receiver. Knowing three of these parameters a priori, LME can be used to estimate the third parameter, such as source depth. Here, the work in Pereira et al. (2016) was expanded to estimate the depth of a vocalizing fin whale recorded by an ocean-bottom seismometer (OBS). In Pereira et al. (2016), the depth of a vocalizing fin whale was inferred by manually comparing spectrograms of LME transmission loss models with observed LME. This study developed an automated procedure to perform the same task using the LME interference pattern observed in the spectrograms of the hydrophone and the vertical channel of the OBS. The results show that the joint use of the two channels was the best approach to estimate a source depth using LME. LME provides a non-intrusive approach for estimating the depth at which a fin whale was vocalizing.


Assuntos
Baleia Comum , Acústica , Animais , Vocalização Animal
14.
J Acoust Soc Am ; 147(4): 2235, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32359319

RESUMO

Fin whales were once abundant in the seas to the southwest of Portugal, but whaling activities decreased their numbers considerably. Acoustic data from ocean bottom seismometers provide an opportunity to detect fin whales from their notes, data that would otherwise be logistically challenging and expensive to obtain. Based on inter-note interval and frequency bandwidth, two acoustic patterns produced by fin whales were detected in the study area: pattern 1, described from fin whales in the Mediterranean Sea, and pattern 2, associated with fin whales from the northeast North Atlantic Ocean (NENA). NENA fin whales travel into the western Mediterranean Sea, but the Mediterranean population has not been documented to travel regularly into the NENA. In this study, 11 months of acoustic data recorded southwest of Portugal in the NENA were used to characterize 20-Hz fin whale notes into these patterns. Pattern 2 was the most common and occurred mostly in November-January. Pattern 1 occurred less frequently and mostly in September-December, February and April, which suggested a limited excursion of whales from the Mediterranean Sea. There were also occasions when the two patterns were recorded simultaneously. Results suggest that fin whales from the NENA and Mediterranean Sea might mix in the area during part of the year.


Assuntos
Baleia Comum , Acústica , Animais , Oceano Atlântico , Mar Mediterrâneo , Portugal
15.
Neural Plast ; 2019: 8136354, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341470

RESUMO

The role of attentional mechanisms in peripheral vision loss remains an outstanding question. Our study was aimed at determining the effect of genetically determined peripheral retinal dystrophy caused by Retinitis Pigmentosa (RP) on visual cortical function and tested the recruitment of attentional mechanisms using functional magnetic resonance imaging (fMRI). We included thirteen patients and twenty-two age- and gender-matched controls. We analyzed cortical responses under attentional demands and passive viewing conditions while presenting a visual stimulus covering the central and paracentral visual field. Brain activity was studied in visual areas V1, V2, and V3 as well as in cortical regions of interest corresponding to the preserved and the damaged visual field. The influence of visual field extent and age of disease onset were also investigated. Cortical thickness of visual areas was also measured. We found that cortical visual responses under attentional demands were increased in patients with larger degeneration of visual field, as demonstrated by significant interaction effects between group and task conditions. Moreover, activation during the task condition was increased for patients in two cortical regions of interest corresponding to the preserved and damaged visual field, specifically in patients with severe visual field loss. These findings were observed in the presence of preserved visual cortical structure. We conclude that RP patients have enhanced visual attention recruitment despite their retinal degeneration, while cortical structure and overall response levels remain intact. The unmasking of feedback signals from higher level visual regions involved in attentional processes may explain the increased cortical responses. These findings are relevant for the design of strategies for treating retinal diseases, based on attentional cuing.


Assuntos
Atenção/fisiologia , Retinose Pigmentar/diagnóstico por imagem , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Degeneração Retiniana/diagnóstico por imagem , Degeneração Retiniana/fisiopatologia , Retinose Pigmentar/fisiopatologia , Campos Visuais/fisiologia , Adulto Jovem
16.
Molecules ; 24(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703341

RESUMO

Culinary herbs and spices are widely used as a traditional medicine in the treatment of diabetes and its complications, and there are several scientific studies in the literature supporting the use of these medicinal plants. However, there is often a lack of knowledge on the bioactive compounds of these herbs and spices and their mechanisms of action. The aim of this study was to use inverse virtual screening to provide insights into the bioactive compounds of common herbs and spices, and their potential molecular mechanisms of action in the treatment of diabetes. In this study, a library of over 2300 compounds derived from 30 common herbs and spices were screened in silico with the DIA-DB web server against 18 known diabetes drug targets. Over 900 compounds from the herbs and spices library were observed to have potential anti-diabetic activity and liquorice, hops, fennel, rosemary, and fenugreek were observed to be particularly enriched with potential anti-diabetic compounds. A large percentage of the compounds were observed to be potential polypharmacological agents regulating three or more anti-diabetic drug targets and included compounds such as achillin B from yarrow, asparasaponin I from fenugreek, bisdemethoxycurcumin from turmeric, carlinoside from lemongrass, cinnamtannin B1 from cinnamon, crocin from saffron and glabridin from liquorice. The major targets identified for the herbs and spices compounds were dipeptidyl peptidase-4 (DPP4), intestinal maltase-glucoamylase (MGAM), liver receptor homolog-1 (NR5A2), pancreatic alpha-amylase (AM2A), peroxisome proliferator-activated receptor alpha (PPARA), protein tyrosine phosphatase non-receptor type 9 (PTPN9), and retinol binding protein-4 (RBP4) with over 250 compounds observed to be potential inhibitors of these particular protein targets. Only bay leaves, liquorice and thyme were found to contain compounds that could potentially regulate all 18 protein targets followed by black pepper, cumin, dill, hops and marjoram with 17 protein targets. In most cases more than one compound within a given plant could potentially regulate a particular protein target. It was observed that through this multi-compound-multi target regulation of these specific protein targets that the major anti-diabetic effects of reduced hyperglycemia and hyperlipidemia of the herbs and spices could be explained. The results of this study, taken together with the known scientific literature, indicated that the anti-diabetic potential of common culinary herbs and spices was the result of the collective action of more than one bioactive compound regulating and restoring several dysregulated and interconnected diabetic biological processes.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Inibidores Enzimáticos , Hipoglicemiantes , Plantas Medicinais/química , Especiarias , Diabetes Mellitus/enzimologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêutico , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico
17.
Molecules ; 24(10)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137754

RESUMO

Medicinal plants containing complex mixtures of several compounds with various potential beneficial biological effects are attractive treatment interventions for a complex multi-faceted disease like diabetes. In this study, compounds identified from African medicinal plants were evaluated for their potential anti-diabetic activity. A total of 867 compounds identified from over 300 medicinal plants were screened in silico with the DIA-DB web server (http://bio-hpc.eu/software/dia-db/) against 17 known anti-diabetic drug targets. Four hundred and thirty compounds were identified as potential inhibitors, with 184 plants being identified as the sources of these compounds. The plants Argemone ochroleuca, Clivia miniata, Crinum bulbispermum, Danais fragans, Dioscorea dregeana, Dodonaea angustifolia, Eucomis autumnalis, Gnidia kraussiana, Melianthus comosus, Mondia whitei, Pelargonium sidoides, Typha capensis, Vinca minor, Voacanga Africana, and Xysmalobium undulatum were identified as new sources rich in compounds with a potential anti-diabetic activity. The major targets identified for the natural compounds were aldose reductase, hydroxysteroid 11-beta dehydrogenase 1, dipeptidyl peptidase 4, and peroxisome proliferator-activated receptor delta. More than 30% of the compounds had five or more potential targets. A hierarchical clustering analysis coupled with a maximum common substructure analysis revealed the importance of the flavonoid backbone for predicting potential activity against aldose reductase and hydroxysteroid 11-beta dehydrogenase 1. Filtering with physiochemical and the absorption, distribution, metabolism, excretion and toxicity (ADMET) descriptors identified 28 compounds with favorable ADMET properties. The six compounds-crotofoline A, erythraline, henningsiine, nauclefidine, vinburnine, and voaphylline-were identified as novel potential multi-targeted anti-diabetic compounds, with favorable ADMET properties for further drug development.


Assuntos
Hipoglicemiantes/análise , Hipoglicemiantes/farmacologia , Internet , Plantas Medicinais/química , Interface Usuário-Computador , Disponibilidade Biológica , Hipoglicemiantes/química , Simulação de Acoplamento Molecular
18.
Biochim Biophys Acta Bioenerg ; 1859(8): 591-601, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29719209

RESUMO

Sit4p is a type 2A-related protein phosphatase in Saccharomyces cerevisiae involved in a wide spectrum of cellular functions, including the glucose repression of mitochondrial transcription. Here we report that Sit4p is also involved in post-translational regulation of mitochondrial proteins and identified 9 potential targets. One of these, the ATP synthase (FoF1 complex) beta subunit Atp2p, was characterized and two phosphorylation sites, T124 and T317, were identified. Expression of Atp2p-T124 or T317 phosphoresistant versions in sit4Δ cells decreased Atp2p phosphorylation confirming these as Sit4p-regulated sites. Moreover, Sit4p and Atp2p interacted both physically and genetically. Mimicking phosphorylation at T124 or T317 increased Atp2p levels, resulting in higher abundance/activity of ATP synthase. Similar changes were observed in sit4Δ cells in which Atp2p is endogenously more phosphorylated. Expression of Atp2-T124 or T317 phosphomimetics also increased mitochondrial respiration and ATP levels and extended yeast lifespan. These results suggest that Sit4p-mediated dephosphorylation of Atp2p-T124/T317 downregulates Atp2p alongside with ATP synthase and mitochondrial function. Combination of transcriptional with post-translational regulation during fermentative growth may allow for a more efficient Sit4p repression of mitochondrial respiration.


Assuntos
Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Proteína Fosfatase 2/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Trifosfato de Adenosina/metabolismo , Regulação Fúngica da Expressão Gênica , Fosforilação , Saccharomyces cerevisiae/crescimento & desenvolvimento
19.
Genet Mol Biol ; 41(4): 766-774, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30571812

RESUMO

The utility of genetic risk scores (GRS) as independent risk predictors remains inconclusive. Here, we evaluate the additive value of a multi-locus GRS to the Framingham risk score (FRS) in coronary artery disease (CAD) risk prediction. A total of 2888 individuals (1566 coronary patients and 1322 controls) were divided into three subgroups according to FRS. Multiplicative GRS was determined for 32 genetic variants associated to CAD. Logistic Regression and Area Under the Curve (AUC) were determined first, using the TRF for each FRS subgroup, and secondly, adding GRS. Different models (TRF, TRF+GRS) were used to classify the subjects into risk categories for the FRS 10-year predicted risk. The improvement offered by GRS was expressed as Net Reclassification Index and Integrated Discrimination Improvement. Multivariate analysis showed that GRS was an independent predictor for CAD (OR = 1.87; p<0.0001). Diabetes, arterial hypertension, dyslipidemia and smoking status were also independent CAD predictors (p<0.05). GRS added predictive value to TRF across all risk subgroups. NRI showed a significant improvement in all categories. In conclusion, GRS provided a better incremental value in intermediate subgroup. In this subgroup, inclusion of genotyping may be considered to better stratify cardiovascular risk.

20.
Int J Clin Pract ; 71(6)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28503909

RESUMO

Several genetic risk scores (GRS) have been associated with cardiovascular disease; their role, however, in survival from proven coronary artery disease (CAD) have yielded conflicting results. OBJECTIVE: The objective of this study was to evaluate long-term cardiovascular mortality according to the genetic risk score in a Southern European population with CAD. METHODS: A cohort of 1464 CAD patients with angiographic proven CAD were followed up prospectively for up to 58.3 (interquartile range: 25.8-88.1) months. Genotyping of 32 single-nucleotide polymorphisms previously associated with CAD was performed using oligonucleotides probes marked with fluorescence for each allele. GRS was constructed according to the additive model assuming codominance and categorised using the median (=26). Cox Regression analysis was performed to determine independent multivariate predictors of cardiovascular mortality. Kaplan-Meier survival curves compared high vs low GRS using log-rank test. C-index was done for our population, as a measure of discrimination in survival analysis model. RESULTS: During a mean follow-up of 58.3 months, 156 patients (10.7%) died, 107 (7.3%) of CV causes. High GRS (≥26) was associated with reduced cardiovascular survival. Survival analysis with Cox regression model adjusted for 8 variables showed that high GRS, dyslipidemia, diabetes and 3-vessel disease were independent risk factors for cardiovascular mortality (HR=1.53, P=.037; HR=3.64, P=.012; HR=1.75, P=.004; HR=2.97, P<.0001, respectively). At the end of follow-up, the estimated survival probability was 70.8% for high GRS and 80.8% for low GRS (Log-rank test 5.6; P=.018). C-Index of 0.71 was found when GRS was added to a multivariate survival model of diabetes, dyslipidemia, smoking, hypertension and 3 vessel disease, stable angina and dual antiplatelet therapy. CONCLUSIONS: Besides the classical risk factors management, this work highlights the relevance of the genetic profile in survival from CAD. It is expected that new therapies will be dirsected to gene targets with proven value in cardiovascular survival.


Assuntos
Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/mortalidade , Idoso , Estudos de Coortes , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Portugal , Análise de Regressão , Fatores de Risco , Análise de Sobrevida
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