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1.
3 Biotech ; 14(3): 92, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38425411

RESUMO

Polysaccharide-rich materials were extracted from the alcohol-insoluble solids of Olea europaea l. **leaves. Structural characteristics were determined by colorimetric techniques, FT-IR, GC-MS, SEC/MALS/VD/DRI, and NMR (1H,13C). The extract and its main macromolecular components were characterized to assess their ability toward antioxidant, α-amylase inhibition, and antiproliferative activities. Results revealed that the ultrasound olive leave extract comprises polysaccharides with uronic acid, galactose, arabinose, and glucose in molar percentages of 11.7%, 11.3%, 7.5%, and 4.9% respectively, constituting 41% of the total mass. In addition, polyphenols (21%) and proteins (9%) are associated with these polysaccharides. Further, the extract showed noticeable ORAC and free radical scavenging abilities, in addition to high in vitro antiproliferative activity against Caco-2 colon carcinoma cell lines. Similarly, the extract exhibited a strong, uncompetitive inhibition of α-amylase by 75% in the presence of the extract with 0.75 µg/mL of concentration. This research concludes that ultrasound extraction method can be used for the extraction of polysaccharide-polyphenol-protein complexes. These conjugates exhibit the potential for combined biological activities resulting from a synergistic effect of its compounds, making them promising ingredients for the development of functional food.

2.
Bioorg Chem ; 146: 107255, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38457955

RESUMO

Monoaminooxidases (MAOs) are important targets for drugs used in the treatment of neurological and psychiatric disorders and particularly on Parkinson's Disease (PD). Compounds containing a trans-stilbenoid skeleton have demonstrated good selective and reversible MAO-B inhibition. Here, twenty-two (Z)-3-benzylidenephthalides (benzalphthalides, BPHs) displaying a trans-stilbenoid skeleton have been synthesised and evaluated as inhibitors of the MAO-A and MAO-B isoforms. Some BPHs have selectively inhibited MAO-B, with IC50 values ranging from sub-nM to µM. The most potent compound with IC50 = 0.6 nM was the 3',4'-dichloro-BPH 16, which showed highly selective and reversible MAO-B inhibitory activity. Furthermore, the most selective BPHs displayed a significant protection against the apoptosis, and mitochondrial toxic effects induced by 6-hydroxydopamine (6OHDA) on SH-SY5Y cells, used as a cellular model of PD. The results of virtual binding studies on the most potent compounds docked in MAO-B and MAO-A were in agreement with the potencies and selectivity indexes found experimentally. Additionally, related to toxicity risks, drug-likeness and ADME properties, the predictions found for the most relevant BPHs in this research were within those ranges established for drug candidates.


Assuntos
Neuroblastoma , Doença de Parkinson , Estilbenos , Humanos , Inibidores da Monoaminoxidase/química , Simulação de Acoplamento Molecular , Monoaminoxidase/metabolismo , Doença de Parkinson/tratamento farmacológico , Relação Estrutura-Atividade
3.
Anat Rec (Hoboken) ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38357774

RESUMO

Tamandua mexicana is an anteater species native from Mexico to Peru. This species is of great evolutionary interest because it belongs to one of the oldest clades of placental mammals in the American continent. This study aimed to describe the origin, insertion, and arterial supply of the intrinsic shoulder and brachial muscles of T. mexicana. We also compared the masses of the functional groups. Gross dissections were performed on both thoracic limbs of 13 cadavers. ANOVA followed by Tukey's test was used for statistical analyses. The subscapularis muscle presents a hiatus to the common tendon of the caput breve of the biceps brachii and coracobrachialis muscles. A variant accessory muscle, the m. articularis humeri lateralis, was found on the lateral surface of the shoulder joint. M. deltoideus pars acromialis has two bellies. The teres major muscle is perforated by the aponeurotic origin of the m. tensor fasciae antebrachii. The triceps brachii has two capita longi. The caput mediale is fused with the m. anconeus medialis. The caput laterale can have an accessory belly as an anatomical variant. Among the functional groups, a significant difference was found between the elbow extensors and flexors, with the latter having the lowest mass. In conclusion, the intrinsic muscles of T. mexicana presented unique features for the species, as well as arrangements in mass distribution that evidence a possible evolutionary convergence among species of the Superorder Xenarthra.

4.
Heliyon ; 10(4): e26111, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390136

RESUMO

Introduction: Opioids are widely used for pain management, and increased intracranial pressure (ICP) has been evidenced in some cases. We reported a patient with severe cerebral edema after initiating methadone and its complete resolution upon discontinuing the medication. Additionally, a review of the literature is made. Case report: A 53-year-old woman patient with a history of systemic lupus erythematosus developed mechanic chronic lower back pain, refractory to conventional treatments. She presented improvement with oxycodone. She withdrew this medication due to a lack of supplies in her country (Colombia) and showed withdrawal symptoms. She consulted the emergency department, where oral methadone was started and symptom control was achieved. Three days after admission, she presented intense headaches and emesis. A brain CT scan was performed in which severe cerebral edema was appreciated. Methadone was discontinued, and neurological symptoms quickly disappeared. A follow-up brain CT scan was performed later, finding full resolution of the edema. Conclusion: A case of severe cerebral edema associated with the initiation of oral methadone and its rapid resolution without neurological sequelae after its withdrawal is presented, clinicians must be attentive to this adverse event.

6.
Foods ; 12(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37959141

RESUMO

The pomace olive oil sector needs to improve its use of the main olive oil by-product, called alperujo, which is currently used mainly for combustion after extraction of pomace oil, with all the problems this process entails due to the high degree of humidity, organic load and phytotoxic substances. In this work, a solution at an industrial level that uses thermo-malaxation at a temperature close to 65 °C for one or two hours followed by centrifugation in three phases is proposed. In this way, over 40% of the pomace oil that is rich in minor compounds, a solid with a lower degree of humidity (55%), and a liquid aqueous fraction that is rich in bioactive compounds such as phenolics and sugars are obtained. This aqueous fraction can be treated through subsequent storage stages to increase its content of the main phenolic, hydroxytyrosol, to up to 1.77 g/L, decreasing its percentage of insoluble solids by up to 1.9%, making it possible to obtain extracts that are rich in hydroxytyrosol using systems that are commonly in place at the industrial level. The aqueous fraction, without phenolics, could be used for energy production. A solid with a slightly higher fat content than the initial alperujo remains, thus the rest of the oil content can be extracted from it using solvent, making it, once defatted, suitable for application in subsequent bioprocesses.

7.
Foods ; 12(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38002223

RESUMO

The pectin from the cell walls of olive waste (alperujo) and apple, orange and strawberry fruits was extracted using choline chloride (ChCl) and the yield and chemical and structural compositions were compared to pectin extracted using citric acid (CA) and ammonium oxalate/oxalic acid (AOOA). According to the results, the alperujo pectin extracted using ChCl from alcohol-insoluble residue (AIR) showed a higher yield (2.20-2.88% on the basis of dry weight of AIR) than using CA (0.65-1.22%) but lower than using AOOA (3.92-5.42%). For fruit pectin, the highest yield was obtained using CA (8.81-16%), followed by AOOA (5.4-6.63%), although for apple pectin, ChCl gave a similar yield (5.36%) to AOOA. The uronic acid contents in all ChCl pectins (45.9-70.6% dry basis AIR) were higher or similar to that of the other extracting agents (30.6-65.2%), although a lower level of neutral sugar side chains was detected, with a lower degree of branching and degree of methylation. The NMR and FT-IR spectroscopy of the pectin isolated using ChCl confirmed its slightly different structural composition with respect to CA and AOOA pectin. Therefore, depending on the source material and functionality, pectin isolated using ChCl could be an acid-free alternative to pectin production.

8.
Nat Metab ; 5(8): 1290-1302, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37460843

RESUMO

Having direct access to brain vasculature, astrocytes can take up available blood nutrients and metabolize them to fulfil their own energy needs and deliver metabolic intermediates to local synapses1,2. These glial cells should be, therefore, metabolically adaptable to swap different substrates. However, in vitro and in vivo studies consistently show that astrocytes are primarily glycolytic3-7, suggesting glucose is their main metabolic precursor. Notably, transcriptomic data8,9 and in vitro10 studies reveal that mouse astrocytes are capable of mitochondrially oxidizing fatty acids and that they can detoxify excess neuronal-derived fatty acids in disease models11,12. Still, the factual metabolic advantage of fatty acid use by astrocytes and its physiological impact on higher-order cerebral functions remain unknown. Here, we show that knockout of carnitine-palmitoyl transferase-1A (CPT1A)-a key enzyme of mitochondrial fatty acid oxidation-in adult mouse astrocytes causes cognitive impairment. Mechanistically, decreased fatty acid oxidation rewired astrocytic pyruvate metabolism to facilitate electron flux through a super-assembled mitochondrial respiratory chain, resulting in attenuation of reactive oxygen species formation. Thus, astrocytes naturally metabolize fatty acids to preserve the mitochondrial respiratory chain in an energetically inefficient disassembled conformation that secures signalling reactive oxygen species and sustains cognitive performance.


Assuntos
Astrócitos , Encéfalo , Camundongos , Animais , Astrócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Encéfalo/metabolismo , Cognição , Ácidos Graxos/metabolismo
9.
Neurobiol Dis ; 184: 106199, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37321421

RESUMO

Mitochondrial reactive oxygen species (mROS) have been generally considered harmful byproducts wanted to clear when elevated to avoid brain damage. However, the abundance of mROS in astrocytes is very high -about one order of magnitude above that in neurons-, despite they are essential to preserve cell metabolism and animal behavior. Here, we have focused on this apparent ambiguity by discussing (i) the intrinsic mechanisms accounting for the higher production of mROS by the mitochondrial respiratory chain in astrocytes than in neurons, (ii) the specific molecular targets of astrocytic beneficial mROS, and (iii) how decreased astrocytic mROS causes excess neuronal mROS leading to cellular and organismal damage. We hope that this mini-review serves to clarifying the apparent controversy on the beneficial versus deleterious faces of ROS in the brain from molecular to higher-order organismal levels.


Assuntos
Encéfalo , Mitocôndrias , Animais , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Encéfalo/metabolismo
11.
Antioxidants (Basel) ; 12(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37371892

RESUMO

The olive oil sector is continuously evolving in order to improve the quality of olive oil and its by-products. In fact, the trend is to use increasingly greener olives to improve quality by decreasing the extraction yield, thus obtaining a higher content of antioxidant phenolics. The application of a cold-pressing system to the olive before the extraction of oil was tested with three varieties: picual at three different stages of maturity and arbequina and hojiblanca at early stages of maturity. The Abencor system was used for the extraction of virgin olive oil and its by-products. For the quantification of phenols and total sugars for all phases, organic solvent extractions and colorimetric measurements and high-performance liquid chromatography (HPLC) with a UV detector were used. The results show that the new treatment significantly improved the amount of oil extracted by between 1 and 2% and even increased its concentration of total phenols by up to 33%. Regarding the by-products, the concentrations of the main phenols, such as hydroxytyrosol, increased by almost 50%, as did the glycoside. The treatment also facilitated the separation of phases in by-products and improved the phenolic profile, although not in terms of total phenols, but individual phenols with higher antioxidant activity were obtained.

12.
Nature ; 618(7964): 365-373, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225978

RESUMO

Birth presents a metabolic challenge to cardiomyocytes as they reshape fuel preference from glucose to fatty acids for postnatal energy production1,2. This adaptation is triggered in part by post-partum environmental changes3, but the molecules orchestrating cardiomyocyte maturation remain unknown. Here we show that this transition is coordinated by maternally supplied γ-linolenic acid (GLA), an 18:3 omega-6 fatty acid enriched in the maternal milk. GLA binds and activates retinoid X receptors4 (RXRs), ligand-regulated transcription factors that are expressed in cardiomyocytes from embryonic stages. Multifaceted genome-wide analysis revealed that the lack of RXR in embryonic cardiomyocytes caused an aberrant chromatin landscape that prevented the induction of an RXR-dependent gene expression signature controlling mitochondrial fatty acid homeostasis. The ensuing defective metabolic transition featured blunted mitochondrial lipid-derived energy production and enhanced glucose consumption, leading to perinatal cardiac dysfunction and death. Finally, GLA supplementation induced RXR-dependent expression of the mitochondrial fatty acid homeostasis signature in cardiomyocytes, both in vitro and in vivo. Thus, our study identifies the GLA-RXR axis as a key transcriptional regulatory mechanism underlying the maternal control of perinatal cardiac metabolism.


Assuntos
Ácidos Graxos , Glucose , Coração , Leite Humano , Ácido gama-Linolênico , Feminino , Humanos , Recém-Nascido , Gravidez , Cromatina/genética , Ácidos Graxos/metabolismo , Ácido gama-Linolênico/metabolismo , Ácido gama-Linolênico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Coração/efeitos dos fármacos , Coração/embriologia , Coração/crescimento & desenvolvimento , Homeostase , Técnicas In Vitro , Leite Humano/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Receptores X de Retinoides/metabolismo , Fatores de Transcrição/metabolismo
13.
Food Chem ; 419: 136073, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030208

RESUMO

The main by-product from olive oil extraction (alperujo) was extracted with hot water, citric acid, natural deep eutectic solvent (choline chloride: citric acid), and only choline chloride. The purified extracts were composed of macromolecular complexes constituting polyphenols associated with pectin. The extracts were structurally characterized by FT-IR and solid-NMR spectroscopy and an in vitro test revealed distinct antioxidant and antiproliferative activity, depending on the extracting agents. The choline chloride-extracted complex contained the highest amount of polyphenols among the examined agents, which exhibited a strong antioxidant activity and significant antiproliferative capacity. However, the complex extracted by hot water showed the highest antiproliferative capacity in vitro against the colon carcinoma Caco-2 cell line. In this finding, choline chloride could be used as a novel, green and promising alternative to the conventional extracting agent for the production of complexes that combine the antioxidant activity of phenolic compounds and the physiological effects of pectic polysaccharides.


Assuntos
Olea , Polifenóis , Humanos , Pectinas/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Colina/química , Antioxidantes/química , Células CACO-2 , Espectroscopia de Infravermelho com Transformada de Fourier , Solventes/química , Água/química , Ácido Cítrico
14.
Biomed Opt Express ; 14(4): 1562-1578, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078059

RESUMO

Adaptive optics, in combination with multi-photon techniques, is a powerful approach to image deep into a specimen. Remarkably, virtually all adaptive optics schemes today rely on wavefront modulators that are reflective, diffractive or both. This, however, can pose a severe limitation for applications. Here, we present a fast and robust sensorless adaptive optics scheme adapted for transmissive wavefront modulators. We study our scheme in numerical simulations and in experiments with a novel, optofluidic wavefront shaping device that is transmissive, refractive, polarisation-independent, and broadband. We demonstrate scatter correction of two-photon-excited fluorescence images of microbeads as well as brain cells and benchmark our device against a liquid-crystal spatial light modulator. Our method and technology could open new routes for adaptive optics in scenarios where previously, the restriction to reflective and diffractive devices may have staggered innovation and progress.

15.
Essays Biochem ; 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36866606

RESUMO

Astrocytes are a type of non-neuronal, glial cells, anatomically placed in the intersection between the brain blood vessels and other neural cells-including neurons. Such a strategic situation confers these cells a unique opportunity to sense circulating molecules and adapt according to different organismal conditions. By acting as sentinel cells, astrocytes thus co-ordinate gene expression profiles, immune responses, signal transduction pathways, and metabolic programs that play essential roles in the formation of brain circuits to modulate neurotransmission and higher-order organismal functions.

16.
Essays Biochem ; 67(1): 17-26, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36805653

RESUMO

Astrocytes show unique anatomical, morphological, and metabolic features to take up substrates from the blood and metabolize them for local delivery to active synapses to sustain neuron function. In the present review, we specifically focus on key molecular aspects of energy and redox metabolism that facilitate this astrocyte-neuronal coupling in a controlled manner. Basal glycolysis is co-ordinated by the anaphase-promoting complex/cyclosome (APC/C)-Cdh1, a ubiquitin ligase that targets the proglycolytic enzyme 6-phosphofructokinase-2,6-bisphosphastate-3 (PFKFB3) for degradation. APC/C-Cdh1 activity is more robust in neurons than in astrocytes, which determine that PFKFB3 abundance and glycolytic rate are weaker in neurons. The low PFKFB3 activity in neurons facilitates glucose-6-phosphate oxidation via the pentose-phosphate pathway, which promotes antioxidant protection. Conversely, the high PFKFB3 activity in astrocytes allows the production and release of glycolytic lactate, which is taken up by neurons that use it as an oxidizable substrate. Importantly, the mitochondrial respiratory chain is tighter assembled in neurons than in astrocytes, thus the bioenergetic efficiency of mitochondria is higher in neurons. Because of this, the production of reactive oxygen species (mROS) by mitochondrial complex I is very low in neurons and very high in astrocytes. Such a naturally occurring high abundance of mROS in astrocytes physiologically determines a specific transcriptional fingerprint that contributes to sustaining cognitive performance. We conclude that the energy and redox metabolism of astrocytes must complementarily match that of neurons to regulate brain function and animal welfare.


Assuntos
Astrócitos , Metabolismo Energético , Animais , Astrócitos/metabolismo , Glicólise/fisiologia , Oxirredução , Neurônios/metabolismo
17.
J Neurochem ; 165(4): 521-535, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36563047

RESUMO

Intracellular Ca2+ concentrations are strictly controlled by plasma membrane transporters, the endoplasmic reticulum, and mitochondria, in which Ca2+ uptake is mediated by the mitochondrial calcium uniporter complex (MCUc), while efflux occurs mainly through the mitochondrial Na+ /Ca2+ exchanger (NCLX). RNAseq database repository searches led us to identify the Nclx transcript as highly enriched in astrocytes when compared with neurons. To assess the role of NCLX in mouse primary culture astrocytes, we inhibited its function both pharmacologically or genetically. This resulted in re-shaping of cytosolic Ca2+ signaling and a metabolic shift that increased glycolytic flux and lactate secretion in a Ca2+ -dependent manner. Interestingly, in vivo genetic deletion of NCLX in hippocampal astrocytes improved cognitive performance in behavioral tasks, whereas hippocampal neuron-specific deletion of NCLX impaired cognitive performance. These results unveil a role for NCLX as a novel modulator of astrocytic glucose metabolism, impacting on cognition.


Assuntos
Astrócitos , Cálcio , Camundongos , Animais , Astrócitos/metabolismo , Cálcio/metabolismo , Trocador de Sódio e Cálcio/genética , Mitocôndrias/metabolismo , Glicólise , Cognição , Sódio/metabolismo , Sinalização do Cálcio/fisiologia
18.
Molecules ; 27(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36500472

RESUMO

The main by-product generated from the olive oil two-phase extraction system, or alperujo, is undoubtedly a rich source of bioactive components, among which phenolics are one of the most important. The evolution of four of its main phenolics: hydroxytyrosol (HT), hydroxytyrosol 4-ß-d-glucoside (Glu-HT), 3,4-dihydroxyphenylglycol (DHPG) and tyrosol (Ty) was studied over two seasons and in ten oil mills under similar climatological and agronomic conditions, for the first time using organic extraction and high-performance liquid chromatography (HPLC-DAD) determination. The results show that HT (200-1600 mg/kg of fresh alperujo) and Ty (10-570 mg/kg) increase, while DHPG (10-370 mg/kg) decreases only in the last month of the season and Glu-HT (1400-0 mg/kg) decreases drastically from the beginning. This evolution is similar between different seasons, with a high correlation between Glu-HT, HT, and Ty. On the other hand, it has been verified that a mixture of alperujos from all the oil mills, which is what the pomace extractor receives, is a viable source of a liquid fraction which is rich in the phenolics studied through organic extractions and especially after the application of a thermal treatment, obtaining values of 4.2 g/L of HT, 0.36 g/L of DHPG, and 0.49 g/L of Ty in the final concentrated liquid fraction.


Assuntos
Olea , Álcool Feniletílico , Azeite de Oliva/análise , Glucosídeos , Resíduos Sólidos/análise , Álcool Feniletílico/química , Fenóis/análise , Olea/química
19.
Antioxidants (Basel) ; 11(10)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36290637

RESUMO

The growing interest in natural compounds is helping to improve the management of agro-industrial by-products such as the date seed as sources of such compounds. In this work, the application of a hydrothermal treatment at 160 and 180 °C for 60 min was studied to achieve the solubilization of its phenolic components and sugars in order to obtain biologically active extracts. The percentage of phenols and total sugars in the final extracts were very similar, at 45 and 25% for the 160 and 180 °C treatments, respectively. The treatment at a higher temperature allowed greater solubilization of other components. The antioxidant activity was measured as free-radical scavenging capacity. For the DPPH• method, expressed as EC50, the results were 0.34 and 0.37 mg/L, the TEAC values for the ABTS• method were 6.61 and 3.28 mg/g dried extract, and the values obtained by the ORAC method were 12.82 and 9.91 mmol Trolox/g dried extract, for 160 and 180 °C, respectively. All these values are higher than those of other plant extracts and extracts obtained using the whole date. Therefore, the date seed is a very important source of phenols, and through thermal and chromatographic processes, it is possible to obtain extracts with high antioxidant activity.

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