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1.
Am J Physiol Endocrinol Metab ; 326(5): E555-E566, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38446637

RESUMEN

Prenatal exposure to maternal diabetes has been recognized as a significant cardiovascular risk factor, increasing the susceptibility to the emergence of conditions such as high blood pressure, atherosclerosis, and heart disease in later stages of life. However, it is unclear if offspring exposed to diabetes in utero have worse vascular outcomes on a high-salt (HS) diet. To test the hypothesis that in utero exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, we treated adult male wild-type offspring (DM_Exp, 6 mo old) of diabetic Ins2+/C96Y mice (Akita mice) with HS (8% sodium chloride, 10 days) and analyzed endothelial function via wire myograph and cyclooxygenase (COX)-derived prostanoids pathway by ELISA, quantitative PCR, and immunochemistry. On a regular diet, DM_Exp mice did not manifest any vascular dysfunction, remodeling, or inflammation. However, HS increased aortic contractility to phenylephrine and induced endothelial dysfunction (analyzed by acetylcholine-induced endothelium-dependent relaxation), vascular hydrogen peroxide production, COX2 expression, and prostaglandin E2 (PGE2) overproduction. Interestingly, ex vivo antioxidant treatment (tempol) or COX1/2 (indomethacin) or COX2 (NS398) inhibitors improved or reverted the endothelial dysfunction in DM_Exp mice fed a HS diet. Finally, DM_Exp mice fed with HS exhibited greater circulating cytokines and chemokines accompanied by vascular inflammation. In summary, our findings indicate that prenatal exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, primarily through the induction of oxidative stress and the generation of COX2-derived PGE2. This supports the concept that in utero exposure to maternal diabetes is a cardiovascular risk factor in adulthood.NEW & NOTEWORTHY Using a unique mouse model of prenatal exposure to maternal type 1 diabetes, our study demonstrates the novel observation that prenatal exposure to maternal diabetes results in a predisposition to high-salt (HS) dietary-induced vascular dysfunction and inflammation in adulthood. Mechanistically, we demonstrated that in utero exposure to maternal diabetes and HS intake induces vascular oxidative stress, cyclooxygenase-derived prostaglandin E2, and inflammation.


Asunto(s)
Diabetes Gestacional , Endotelio Vascular , Efectos Tardíos de la Exposición Prenatal , Prostaglandinas , Animales , Femenino , Ratones , Embarazo , Ciclooxigenasa 2/metabolismo , Diabetes Gestacional/metabolismo , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Inflamación/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Prostaglandinas/metabolismo , Cloruro de Sodio Dietético/efectos adversos , Cloruro de Sodio Dietético/metabolismo
2.
Am J Physiol Endocrinol Metab ; 327(1): E1-E12, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38690939

RESUMEN

High levels of testosterone (Testo) are associated with cardiovascular risk by increasing reactive oxygen species (ROS) formation. NADPH oxidases (NOX) are the major source of ROS in the vasculature of cardiovascular diseases. NOX4 is a unique isotype, which produces hydrogen peroxide (H2O2), and its participation in cardiovascular biology is controversial. So far, it is unclear whether NOX4 protects from Testo-induced endothelial injury. Thus, we hypothesized that supraphysiological levels of Testo induce endothelial NOX4 expression to attenuate endothelial injury. Human mesenteric vascular endothelial cells (HMECs) and human umbilical vein endothelial cells (HUVEC) were treated with Testo (10-7 M) with or without a NOX4 inhibitor [GLX351322 (10-4 M)] or NOX4 siRNA. In vivo, 10-wk-old C57Bl/6J male mice were treated with Testo (10 mg/kg) for 30 days to study endothelial function. Testo increased mRNA and protein levels of NOX4 in HMECs and HUVECs. Testo increased superoxide anion (O2-) and H2O2 production, which were abolished by NOX1 and NOX4 inhibition, respectively. Testo also attenuated bradykinin-induced NO production, which was further impaired by NOX4 inhibition. In vivo, Testo decreased H2O2 production in aortic segments and triggered endothelial dysfunction [decreased relaxation to acetylcholine (ACh)], which was further impaired by GLX351322 and by a superoxide dismutase and catalase mimetic (EUK134). Finally, Testo led to a dysregulated endothelial cell migration, which was exacerbated by GLX351322. These data indicate that supraphysiological levels of Testo increase the endothelial expression and activity of NOX4 to counterbalance the deleterious effects caused by Testo in endothelial function.NEW & NOTEWORTHY By inducing ROS formation, high levels of testosterone play a major role in the pathogenesis of cardiovascular disease. NOXs are the major sources of ROS in the vasculature of cardiovascular diseases. Herein, we describe a novel compensatory mechanism by showing that NOX4 is a protective oxidant enzyme and counterbalances the deleterious effects of testosterone in endothelial cells by modulating hydrogen peroxide formation.


Asunto(s)
Movimiento Celular , Endotelio Vascular , Células Endoteliales de la Vena Umbilical Humana , Peróxido de Hidrógeno , Ratones Endogámicos C57BL , NADPH Oxidasa 4 , Testosterona , Animales , Humanos , Masculino , Ratones , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotelio Vascular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , NADPH Oxidasa 4/metabolismo , NADPH Oxidasa 4/genética , Especies Reactivas de Oxígeno/metabolismo , Testosterona/farmacología , Testosterona/metabolismo
3.
Clin Sci (Lond) ; 138(17): 1071-1087, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39136472

RESUMEN

Perivascular adipose tissue (PVAT) negatively regulates vascular muscle contraction. However, in the context of obesity, the PVAT releases vasoconstrictor substances that detrimentally affect vascular function. A pivotal player in this scenario is the peptide endothelin-1 (ET-1), which induces oxidative stress and disrupts vascular function. The present study postulates that obesity augments ET-1 production in the PVAT, decreases the function of the nuclear factor erythroid 2-related factor-2 (Nrf2) transcription factor, further increasing reactive oxygen species (ROS) generation, culminating in PVAT dysfunction. Male C57BL/6 mice were fed either a standard or a high-fat diet for 16 weeks. Mice were also treated with saline or a daily dose of 100 mg·kg-1 of the ETA and ETB receptor antagonist Bosentan, for 7 days. Vascular function was evaluated in thoracic aortic rings, with and without PVAT. Mechanistic studies utilized PVAT from all groups and cultured WT-1 mouse brown adipocytes. PVAT from obese mice exhibited increased ET-1 production, increased ECE1 and ETA gene expression, loss of the anticontractile effect, as well as increased ROS production, decreased Nrf2 activity, and downregulated expression of Nrf2-targeted antioxidant genes. PVAT of obese mice also exhibited increased expression of Tyr216-phosphorylated-GSK3ß and KEAP1, but not BACH1 - negative Nrf2 regulators. Bosentan treatment reversed all these effects. Similarly, ET-1 increased ROS generation and decreased Nrf2 activity in brown adipocytes, events mitigated by BQ123 (ETA receptor antagonist). These findings place ET-1 as a major contributor to PVAT dysfunction in obesity and highlight that pharmacological control of ET-1 effects restores PVAT's cardiovascular protective role.


Asunto(s)
Tejido Adiposo , Regulación hacia Abajo , Endotelina-1 , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2 , Obesidad , Especies Reactivas de Oxígeno , Animales , Endotelina-1/metabolismo , Obesidad/metabolismo , Obesidad/fisiopatología , Masculino , Tejido Adiposo/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Bosentán/farmacología , Dieta Alta en Grasa , Ratones , Estrés Oxidativo , Receptor de Endotelina A/metabolismo , Receptor de Endotelina A/genética , Enzimas Convertidoras de Endotelina/metabolismo , Aorta Torácica/metabolismo , Aorta Torácica/efectos de los fármacos , Aorta Torácica/fisiopatología
4.
Genome ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284229

RESUMEN

Eleocharis R. Br. (Cyperaceae) species are known for having holocentric chromosomes, which enable rapid karyotype differentiation. High intra- and interspecific variations in chromosome numbers and genome sizes are documented for different Eleocharis species, frequently accompanied by fluctuations in the repetitive DNA fraction. However, a lack of detailed analysis has hampered a better understanding of the interplay between holocentricity and repetitive DNA evolution in this genus. In our study, we confirmed the holocentricity of Eleocharis chromosomes by immunostaining against the kinetochore protein KNL1 and the cell-cycle dependent posttranslational modifications histone H2AThr121ph and H3S10ph. We further studied the composition and chromosomal distribution of the main satellite DNA repeats found in the newly sequenced species E. maculosa, E. geniculata, E. parodii, E. elegans, and E. montana. Five of the six satellites discovered were arranged in clusters, while EmaSAT14 was distributed irregularly along the chromatid length in a line-like manner. EmaSAT14 monomers were present in a few copies in few species across the Eleocharis phylogenetic tree. Nonetheless, they were accumulated within a restricted group of Maculosae series, subgenus Eleocharis. The data indicates that the amplification and line-like distribution of EmaSAT14 along chromatids may have occurred recently within a section of the genus.

5.
Chromosome Res ; 31(4): 30, 2023 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-37812264

RESUMEN

Structural karyotype changes result from ectopic recombination events frequently associated with repetitive DNA. Although most Phaseolus species present relatively stable karyotypes with 2n = 22 chromosomes, the karyotypes of species of the Leptostachyus group show high rates of structural rearrangements, including a nested chromosome fusion that led to the dysploid chromosome number of the group (2n = 20). We examined the roles of repetitive landscapes in the rearrangements of species of the Leptostachyus group using genome-skimming data to characterize the repeatome in a range of Phaseolus species and compared them to species of that group (P. leptostachyus and P. macvaughii). LTR retrotransposons, especially the Ty3/gypsy lineage Chromovirus, were the most abundant elements in the genomes. Differences in the abundance of Tekay, Retand, and SIRE elements between P. macvaughii and P. leptostachyus were reflected in their total amounts of Ty3/gypsy and Ty1/copia. The satellite DNA fraction was the most divergent among the species, varying both in abundance and distribution, even between P. leptostachyus and P. macvaughii. The rapid turnover of repeats in the Leptostachyus group may be associated with the several rearrangements observed.


Asunto(s)
Phaseolus , Phaseolus/genética , ADN de Plantas/genética , ADN Satélite/genética , Retroelementos , Filogenia , Genoma de Planta , Evolución Molecular
6.
J Nat Prod ; 87(4): 820-830, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38449376

RESUMEN

Snake venoms contain various bradykinin-potentiating peptides (BPPs). First studied for their vasorelaxant properties due to angiotensin converting enzyme (ACE) inhibition, these molecules present a range of binding partners, among them the argininosuccinate synthase (AsS) enzyme. This has renewed interest in their characterization from biological sources and the evaluation of their pharmacological activities. In the present work, the low molecular weight fraction of Bothrops moojeni venom was obtained and BPPs were characterized by mass spectrometry. Eleven BPPs or related peptides were sequenced, and one of them, BPP-Bm01, was new. Interestingly, some oxidized BPPs were detected. The three most abundant peptides were BPP-Bm01, BPP-Bax12, and BPP-13a, and their putative interactions with the AsS enzyme were investigated in silico. A binding cavity for these molecules was predicted, and docking studies allowed their ranking. Three peptides were synthesized and submitted to vasorelaxation assays using rat aortic rings. While all BPPs were active, BPP-Bm01 showed the highest potency in this assay. This work adds further diversity to BPPs from snake venoms and suggests, for the first time, a putative binding pocket for these molecules in the AsS enzyme. This can guide the design of new and more potent AsS activators.


Asunto(s)
Aorta , Bothrops , Oligopéptidos , Péptidos , Serpientes Venenosas , Animales , Ratas , Brasil , Aorta/efectos de los fármacos , Péptidos/farmacología , Péptidos/química , Bradiquinina/farmacología , Masculino , Venenos de Crotálidos/farmacología , Venenos de Crotálidos/química , Ratas Wistar , Venenos de Serpiente/farmacología , Vasodilatadores/farmacología , Vasodilatadores/química , Estructura Molecular
7.
J Water Health ; 22(3): 522-535, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38557568

RESUMEN

The decline in the quality of water resources in the Amazon is very rapid in cities suffering from unplanned urban growth. The region has two defined seasons, winter (wet) and summer (dry), which directly affect the behavior of contaminants in aquatic ecosystems. The aim of this study was to assess the ecological and human health risks associated with the use of the watershed. In addition, an ecological index was proposed: the Quality Index for Aquatic Life, for the risk of contaminants to aquatic life. Sampling was carried out at six points in the Juá watershed. Physicochemical parameters, major anions, metals and total phosphorus were analyzed at both stations between 2020 and 2021. The highest concentrations of contaminants were found in the rainy season, due to the washing away of the banks. In this sense, Cl presented a concentration more than 307 times higher than that permitted by Brazilian legislation (wet). The ecological index showed that the watershed has a high risk of metals such as Cr III and Cr VI for the biota. The human health risk analysis showed a low risk; however, the lack of basic sanitation in the city indicates that monitoring of urban water resources is necessary.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Humanos , Calidad del Agua , Monitoreo del Ambiente , Ecosistema , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , Metales Pesados/análisis , Ríos , China
8.
An Acad Bras Cienc ; 96(suppl 1): e20230616, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39292103

RESUMEN

Cardiovascular diseases, resulting from the deposition of clots in blood vessels, are the leading cause of death worldwide. Fibrinolytic enzymatic activity can catalyze blood clot degradation. Findings show that 36 fungal isolates recovered from Caatinga soils have the potential to produce fibrinolytic protease under submerged conditions. About 58 % of the isolates displayed fibrinolytic activity above 100 U/mL, with Mucor subtilissimus UCP 1262 being the most active. The protease was biochemically and biophysically characterized, showing that the enzyme had a high affinity for SAApNA substrate and was significantly inhibited by fluoride methyl phenyl sulfonyl-C7H7FO2S, suggesting that it is a chymotrypsin-like serine protease. The highest enzyme activity was detected at pH 5.0 and 28 °C. This fibrinolytic protease's far-UV circular dichroism (CD) showed that its secondary structure was primarily α-helical. The purified fibrinolytic enzyme may represent a novel therapeutic agent for treating thrombosis. At temperatures above 65 °C, the enzyme lost all its secondary structure. Its melting temperature was 58.1 °C, the denaturation enthalpy 85.1 kcal/mol, and the denaturation entropy 0.26 kcal/K∙mol.


Asunto(s)
Mucor , Mucor/enzimología , Concentración de Iones de Hidrógeno , Dicroismo Circular , Microbiología del Suelo , Péptido Hidrolasas/química , Péptido Hidrolasas/aislamiento & purificación , Péptido Hidrolasas/metabolismo , Temperatura , Fibrinolíticos/química , Fibrinólisis
9.
Drug Chem Toxicol ; : 1-11, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39155645

RESUMEN

Cardiovascular diseases (CVDs) cause 30% of deaths each year, and in 2030, around 23.6 million people will die due to CVDs. The major challenge is to obtain molecules with minimal adverse reactions that can prevent and dissolve blood clots. In this context, fibrinolytic enzymes from diverse microorganism sources have been extensively investigated due to their potential to act directly and specifically on the fibrin clot, preventing side effects and performing potential thrombolytic effects. However, most researches focus on the purification and characterization of proteases, with little emphasis on the mechanism of action and pharmacological characteristics, including toxicity assays which are essential to assess safety and side effects. Therefore, this work aims to emphasize the importance of evaluations indicating the toxicological profile of fibrinolytic proteases through in vitro and in vivo tests. Both types of assays contribute as preclinical stage in drug development and are crucial for clinical applications. This scarcity creates arbitrary barriers to further studies. This work should further encourage the development of studies to ensure the safety and effectivity of fibrinolytic proteases.


Suggested pre-clinical trials aim to validate more specific methods for fibrinolytic enzymes;Current toxicity standards can be adapted to better assess the profile of fibrinolytic enzymes;The class of fibrinolytic enzymes must be carefully evaluated according to the method of application.

10.
Prep Biochem Biotechnol ; 54(2): 260-271, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37355277

RESUMEN

Collagenases are proteases able to degrade native and denatured collagen, with broad applications such as leather, food, and pharmaceutical industries. The aim of this research was to purify and characterize a collagenase from Streptomyces antibioticus. In the present work, the coffee ground substrate provided conditions to obtaining high collagenase activity (377.5 U/mL) using anion-exchange DEAE-Sephadex G50 chromatographic protocol. SDS-PAGE revealed the metallo-collagenase with a single band of 41.28 kDa and was able to hydrolyzed type I and type V collagen producing bioactive peptides that delayed the coagulation time. The enzyme activity showed stability across a range of pH (6.0-11) and temperature (30-55 °C) with optima at pH 7.0 and 60 °C, respectively. Activators include Mg+2, Ca+2, Na+, K+, while full inhibition was given by other tested metalloproteinase inhibitors. Kinetic parameters (Km of 27.14 mg/mol, Vmax of 714.29 mg/mol/min, Kcat of 79.9 s-1 and Kcat/Km of 2.95 mL/mg/s) and thermodynamic parameters (Ea of 65.224 kJ/mol, ΔH of 62.75 kJ/mol, ΔS of 1.96 J/mol, ΔG of 62.16 kJ/mol, ΔGE-S of 8.18 kJ/mol and ΔGE-T of -2.64 kJ/mol) were also defined. Coffee grounds showed to be an interesting source to obtaining a collagenase able to produce bioactive peptides with anticoagulant activity.


Asunto(s)
Streptomyces antibioticus , Café , Termodinámica , Colagenasas , Péptidos , Concentración de Iones de Hidrógeno , Cinética
11.
Prep Biochem Biotechnol ; 54(4): 545-552, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37667995

RESUMEN

Mushrooms are a source of primary and secondary metabolites. Little is known about the most suitable conditions for production of mushrooms by submerged fermentation. This article reports antioxidant and cytotoxic assays, in addition to quantitatively evaluating the content of proteases with fibrinolytic action in the crude extracts of two species of edible mushrooms produced in different formulations, as well as evaluating the recovery of these enzymes by aqueous two-phase systems (ATPS). The mushrooms Pleurotus ostreatus and Pleurotus eryngii, at concentration of 100 µg/mL, displayed inhibition of DPPH and ABTS radicals below 50%. In the cytotoxicity test, the cells human fibroblast cell lines (MRC-5) showed cell viability greater than 80%. Concerning fibrinolytic activity, P. eryngii presented 226.47 ± 7.26 U/mL, therefore being more efficient than P. ostreatus (71.5 ± 0.56 U/mL). In the recovery of the P. eryngii extract by ATPS, the fibrinolytic protease was partitioned in the salt phase (30.25 U/mL). The molecular mass of the proteases was between 75 and 100 kDa. These results prove the low cytotoxicity of the extracts produced and that fermentation in supplemented malt broth favored the excretion of fibrinolytic proteases compared to the other evaluated media.


Asunto(s)
Agaricales , Antineoplásicos , Pleurotus , Humanos , Antioxidantes/química , Pleurotus/química , Péptido Hidrolasas/metabolismo , Agaricales/química , Endopeptidasas/metabolismo , Antineoplásicos/metabolismo
12.
Theor Appl Genet ; 136(10): 215, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37751069

RESUMEN

KEY MESSAGE: Karyotypes evolve through numerical and structural chromosome rearrangements. We show that Phaseolus leptostachyus, a wild bean, underwent a rapid genome reshuffling associated with the reduction from 11 to 10 chromosome pairs, but without whole genome duplication, the highest chromosome evolution rate known for plants. Plant karyotypes evolve through structural rearrangements often associated with polyploidy or dysploidy. The genus Phaseolus comprises ~ 90 species, five of them domesticated due to their nutritional relevance. Most of the species have 2n = 22 karyotypes and are highly syntenic, except for three dysploid karyotypes of species from the Leptostachyus group (2n = 20) that have accumulated several rearrangements. Here, we investigated the degrees of structural rearrangements among Leptostachyus and other Phaseolus groups by estimating their chromosomal evolution rates (CER). For this, we combined our oligo-FISH barcode system for beans and chromosome-specific painting probes for chromosomes 2 and 3, with rDNA and a centromeric probe to establish chromosome orthologies and identify structural rearrangements across nine Phaseolus species. We also integrated the detected rearrangements with a phylogenomic approach to estimate the CERs for each Phaseolus lineage. Our data allowed us to identify translocations, inversions, duplications and deletions, mostly in species belonging to the Leptostachyus group. Phaseolus leptostachyus showed the highest CER (12.31 rearrangements/My), a tenfold increase in contrast to the 2n = 22 species analysed. This is the highest rate known yet for plants, making it a model species for investigating the mechanisms behind rapid genome reshuffling in early species diversification.


Asunto(s)
Phaseolus , Phaseolus/genética , Cariotipo , Cariotipificación , Centrómero , Reordenamiento Génico
13.
An Acad Bras Cienc ; 95(suppl 1): e20220552, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585969

RESUMEN

A fibrinolytic enzyme from the microalga Dunaliella tertiolecta was produced under mixotrophic conditions using different corn steep liquor (CSL) concentrations ( 0 ≤ CLS ≤ 0.75%), purified using a combination of salting out and ion-exchange chromatography, and then biochemical characterized. Cultivation of this microalga using 0.5% CSL led to the highest maximum cell concentration (1.960±0.010 mg L-1) and cell productivity (0.140g L-1 day-1), besides a high fibrinolytic activity of the extract obtained by the homogenization method (102 ±1 U mL-1). The enzyme extracted from the microalgal biomass was 5-fold purified with a 20% yield and was found to have a specific activity of 670 U mg-1. The enzyme, whose molecular weight determined by fibrin zymography was 10 kDa, was shown to be stable at pH 3.0-9.0 and up to 70°C with optimal pH and temperature values of 8.0 and 50°C, respectively. When compared to other fibrinolytic enzymes, this protease stood out for its high fibrinolytic activity, which was enhanced by Fe2+, inhibited by Zn2+, Cu2+, Mg2+, and Ca2+, and strongly inhibited by phenylmethylsulfonyl fluoride, suggesting that it belongs to the serine metalloprotease family. Moreover, thanks to its thermal stability, the enzyme may be easily preserved and activated under high-temperature conditions.


Asunto(s)
Microalgas , Zea mays , Análisis Costo-Beneficio , Fibrina , Concentración de Iones de Hidrógeno , Temperatura
14.
Neuromodulation ; 26(5): 999-1008, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34309138

RESUMEN

OBJECTIVES: Although primary motor cortex (M1) transcranial direct current stimulation (tDCS) has an analgesic effect in fibromyalgia (FM), its neural mechanism remains elusive. We investigated whether M1-tDCS modulates a regional temporal variability of blood-oxygenation-level-dependent (BOLD) signals, an indicator of the brain's flexibility and efficiency and if this change is associated with pain improvement. MATERIALS AND METHODS: In a within-subjects cross-over design, 12 female FM patients underwent sham and active tDCS on five consecutive days, respectively. Each session was performed with an anode placed on the left M1 and a cathode on the contralateral supraorbital region. The subjects also participated in resting-state functional magnetic resonance imaging (fMRI) at baseline and after sham and active tDCS. We compared the BOLD signal variability (SDBOLD), defined as the standard deviation of the BOLD time-series, between the tDCS conditions. Baseline SDBOLD was compared to 15 healthy female controls. RESULTS: At baseline, FM patients showed reduced SDBOLD in the ventromedial prefrontal cortex (vmPFC), lateral PFC, and anterior insula and increased SDBOLD in the posterior insula compared to healthy controls. After active tDCS, compared to sham, we found an increased SDBOLD in the left rostral anterior cingulate cortex (rACC), lateral PFC, and thalamus. After sham tDCS, compared to baseline, we found a decreased SDBOLD in the dorsomedial PFC and posterior cingulate cortex/precuneus. Interestingly, after active tDCS compared to sham, pain reduction was correlated with an increased SDBOLD in the rACC/vmPFC but with a decreased SDBOLD in the posterior insula. CONCLUSION: Our findings suggest that M1-tDCS might revert temporal variability of fMRI signals in the rACC/vmPFC and posterior insula linked to FM pain. Changes in neural variability would be part of the mechanisms underlying repetitive M1-tDCS analgesia in FM.


Asunto(s)
Fibromialgia , Estimulación Transcraneal de Corriente Directa , Femenino , Humanos , Fibromialgia/diagnóstico por imagen , Fibromialgia/terapia , Imagen por Resonancia Magnética , Dolor , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Estudios Cruzados
15.
J Environ Manage ; 341: 118029, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37172351

RESUMEN

Over the last two decades, forest cover has experienced significant impacts from fires and deforestation worldwide due to direct human activities and climate change. This paper assesses trends in forest cover loss and land use and land cover changes in northern Algeria between 2000 and 2020 using datasets extracted from Google Earth Engine (GEE), such as the Hanssen Global Forest Change and MODIS Land Cover Type products (MCD12Q1). Classification was performed using the pixel-based supervised machine-learning algorithm called Random Forest (RF). Trends were analyzed using methods such as Mann-Kendall and Sen. The study area comprises 17 basins with high rainfall variability. The results indicated that the forest area decreased by 64.96%, from 3718 to 1266 km2, during the 2000-2020 period, while the barren area increased by 40%, from 134,777 to 188,748 km2. The findings revealed that the Constantinois-Seybousse-Mellegue hydrographic basin was the most affected by deforestation and cover loss, exceeding 50% (with an area of 1018 km2), while the Seybouse River basin experienced the highest percentage of cover loss at 40%. Nonparametric tests showed that seven river basins (41%) had significantly increasing trends of forest cover loss. According to the obtained results, the forest loss situation in Algeria, especially in the northeastern part, is very alarming and requires an exceptional and urgent plan to protect forests and the ecological system against wildfires and climate change. The study provides a diagnosis that should encourage better protection and management of forest cover in Algeria.


Asunto(s)
Conservación de los Recursos Naturales , Sistemas de Información Geográfica , Humanos , Conservación de los Recursos Naturales/métodos , Argelia , Agricultura , Monitoreo del Ambiente/métodos , Tecnología
16.
Prep Biochem Biotechnol ; 53(8): 906-913, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36579491

RESUMEN

Fructooligosaccharides (FOS) are prebiotics of interest to the food industry. These compounds can be produced through the transfructosylation reaction by the enzyme fructofuranosidase. This enzyme is widely produced by fungi in a medium rich in sugar. Therefore, in this work, the main objectives were production, purification, biochemical characterization of a novel fructofuranosidase enzyme by Penicillium citreonigrum URM 4459 and synthesize and evaluate the antibacterial potential of fructooligosaccharides. With respect to sucrose hydrolysis, the optimal pH was 5.5, the apparent Km for purified FFase was 3.8 mM, the molecular mass was 43.0 kDa, estimated by gel filtration on Superdex increase G75 controlled by AKTA Avant 25 and confirmed by 10% SDS-PAGE under denaturing condition. Also, the isoelectric point was 4.9. The fractions obtained with enzymatic activities, both stable at acidic pH and high temperatures, as well as being able to produce FOS. Regarding antibacterial activity, the FOS produced in this study showed better results than commercial FOS and other carbon sources. Thus, this work presents relevant data for the use of P. citreonigum to produce fructofuranosidase and consequently FOS and can be used in the food and pharmaceutical industry.


Asunto(s)
Penicillium , beta-Fructofuranosidasa , Oligosacáridos , Concentración de Iones de Hidrógeno
17.
Arch Microbiol ; 204(8): 503, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35852634

RESUMEN

Thrombosis is a hematological disorder characterized by the formation of intravascular thrombi, which contributes to the development of cardiovascular diseases. Fibrinolytic enzymes are proteases that promote the hydrolysis of fibrin, promoting the dissolution of thrombi, contributing to the maintenance of adequate blood flow. The characterization of new effective, safe and low-cost fibrinolytic agents is an important strategy for the prevention and treatment of thrombosis. However, the development of new fibrinolytics requires the use of complex methodologies for purification, physicochemical characterization and evaluation of the action potential and toxicity of these enzymes. In this context, microbial enzymes produced by bacteria of the Bacillus genus are promising and widely researched sources to produce new fibrinolytics, with high thrombolytic potential and reduced toxicity. Thus, this review aims to provide a current and comprehensive understanding of the different Bacillus species used for the production of fibrinolytic proteases, highlighting the purification techniques, biochemical characteristics, enzymatic activity and toxicological evaluations used.


Asunto(s)
Bacillus , Trombosis , Bacterias , Endopeptidasas , Fibrinolíticos/química , Fibrinolíticos/farmacología , Humanos , Péptido Hidrolasas , Trombosis/tratamiento farmacológico
18.
Protein Expr Purif ; 192: 106044, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34998976

RESUMEN

This work reports the immobilization of a fibrinolytic protease (FP) from Mucor subtilissimus UCP 1262 on Fe3O4 magnetic nanoparticles (MNPs) produced by precipitation of FeCl3·6H2O and FeCl2·4H2O, coated with polyaniline and activated with glutaraldehyde. The FP was obtained by solid state fermentation, precipitated with 40-60% ammonium sulfate, and purified by DEAE-Sephadex A50 ion exchange chromatography. The FP immobilization procedure allowed for an enzyme retention of 52.13%. The fibrinolytic protease immobilized on magnetic nanoparticles (MNPs/FP) maintained more than 60% of activity at a temperature of 40 to 60 °C and at pH 7 to 10, when compared to the non-immobilized enzyme. MNPs and MNPs/FP did not show any cytotoxicity against HEK-293 and J774A.1 cells. MNPs/FP was not hemolytic and reduced the hemolysis induced by MNPs from 2.07% to 1.37%. Thrombus degradation by MNPs/FP demonstrated that the immobilization process guaranteed the thrombolytic activity of the enzyme. MNPs/FP showed a total degradation of the γ chain of human fibrinogen within 90 min. These results suggest that MNPs/FP may be used as an alternative strategy to treat cardiovascular diseases with a targeted release through an external magnetic field.


Asunto(s)
Fibrinolíticos/química , Nanopartículas de Magnetita/química , Mucor/enzimología , Péptido Hidrolasas/química , Péptido Hidrolasas/aislamiento & purificación , Cromatografía por Intercambio Iónico , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Enzimas Inmovilizadas/farmacología , Fibrinógeno/química , Fibrinógeno/metabolismo , Fibrinolíticos/aislamiento & purificación , Fibrinolíticos/farmacología , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Mucor/química , Mucor/genética , Péptido Hidrolasas/farmacología , Temperatura
19.
An Acad Bras Cienc ; 94(4): e20201914, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36102391

RESUMEN

Fibrinolytic enzymes are considered promising alternative in the treatment of cardiovascular diseases by preventing fibrin clots. A protease from Mucor subtilissimus UCP 1262 was obtained by solid state fermentation and purified by ion exchange chromatography. The purified extract was administered at an acute dose of 2000 mg/mL to evaluate its toxic effects to the lungs of mice. After 14 days of treatment, a histomorphometric study was performed by the type 1 and 2 pneumocyte count and the evaluation of the lung area. As result, the experimental group showed a significant decrease of type 2 pneumocyte and although a decrease in the alveolar area was observed in relation to the control group, no significant pulmonary toxicity, emphysema, and fibrosis characteristics were detected. The in vitro tests suggest possible clinical applications for the enzyme.


Asunto(s)
Pulmón , Péptido Hidrolasas , Animales , Ratones , Péptido Hidrolasas/química
20.
An Acad Bras Cienc ; 94(4): e20201438, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35830020

RESUMEN

This work aimed to compare the production of collagenolytic proteases produced by M. subtilissimus UCP1262 in submerged fermentation (SF) and solid-state fermentation (SSF) as well as extracting in aqueous two-phase system (ATPS). Collagenolytic protease production was performed in using MS-2 culture medium (SF) and soybean bran as substrate (SSF). Subsequently, the fermented liquid from both fermentations were used for the extraction of enzyme by ATPS, it was verified the influence of different variables from a factorial design 23. In SSF the highest protease and collagenolytic activities were achieved with 362.66 U/mL and 179.81 U/mL, respectively. When compared with SF (26.33 and 18.70 U/mL) higher values were obtained in the activities. The protease partitioning from SF and SSF in ATPS showed a similar profile showing higher affinity for the polymer rich phase. The highest value for the response variable purification factor (3.49) was obtained in the system using SSF. Thus, SSF shows promise as a bioprocess for extracellular production of collagenolytic proteases, using of soybean bran as substrate had used sustainable raw material, aiming application this possible enzyme in the treatment of burns and postoperative scarring.


Asunto(s)
Mucor , Péptido Hidrolasas , Fermentación , Glycine max , Temperatura
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