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1.
Environ Technol ; : 1-9, 2024 Sep 26.
Article in English | MEDLINE | ID: mdl-39324732

ABSTRACT

The removal of the tetra-azo dye Direct Black 22 (DB22) using the microalga Chlorella vulgaris was evaluated in the present study, aiming to understand the contribution of different processes (biodegradation, photodegradation, and adsorption) in the removal of this contaminant. The growth and morphological characteristics of C. vulgaris were not affected by the presence of the dye in the reaction medium. The efficiency of dye removal was 62.6 ± 1.46%, 47.7 ± 7.2% of which was attributed to photodegradation, while 13.2 ± 6.5% were associated with the contribution of the microalga by an enzymatic route and 1.7 ± 9.6% with an adsorption process. Additionally, tests with the organism Allium cepa as a bioindicator revealed that DB22 and its byproducts did not induce toxicity, but cytotoxicity and genotoxicity were induced. We observed that genotoxicity was reduced after the remediation process. Our results establish photodegradation as the primary mechanism and biodegradation as the secondary mechanism driving the removal of DB22 within a Chlorella culture. Researchers must carefully consider all aspects involved in the removal process, including photodegradation, biodegradation, and adsorption processes.

2.
Drug Chem Toxicol ; : 1-11, 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39155645

ABSTRACT

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.

3.
J Chem Phys ; 160(24)2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38920399

ABSTRACT

Improving the catalytic performance of materials based on cerium oxide (CeO2) for the activation of methane (CH4) can be achieved through the following strategies: mixture of CeO2 with different oxides (e.g., CeO2-La2O3) and the use of particles with different sizes. In this study, we present a theoretical investigation of the initial CH4 dehydrogenation on (La2Ce2O7)n clusters, where n = 2, 4, and 6. Our framework relies on density functional theory calculations combined with the unity bond index-quadratic exponential potential approximation. Our results indicate that chemical species arising from the first dehydrogenation of CH4, that is, CH3 and H, bind through the formation of C-O and H-O bonds with the clusters, respectively. The coordination of the adsorption site and the chemical environment plays a crucial role in the magnitude of the adsorption energy; for example, species adsorb more strongly in the low-coordinated topO sites located close to the La atoms. Thus, it affects the activation energy barrier, which tends to be lower in configurations where the adsorption of the chemical species is stronger. During CH4 dehydrogenation, the CH3 radical can be present in a planar or tetrahedral configuration. Its conformation changes as a function of the charge transference between the molecule and the cluster, which depends on the CH3-cluster distance. Finally, we analyze the effects of the Hubbard effective parameter (Ueff) on adsorption properties, as the magnitude of localization of Ce f-states affects the hybridization of the interaction between the molecule and the clusters and hence the magnitude of the adsorption energies. We obtained a linear decrease in the adsorption energies by increasing the Ueff parameter; however, the activation energy is only slightly affected.

4.
Int J Biol Macromol ; 269(Pt 1): 132094, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705318

ABSTRACT

This work presents a magnetic purification method of human erythrocyte Acetylcholinesterase (EC 3.1.1.7; AChE) based on affinity binding to procainamide (Proca) as ligand. Acetylcholinesterase is an acetylcholine-regulating enzyme found in different areas of the body and associated with various neurological disorders, such as Parkinson, Alzheymer and Amyotrophic Lateral Sclerosis. AChE from human erythrocyte purification has been attempted in recent years with low degree of purity. Here, magnetic nanoparticles (MNP) were synthesized and coated with polyaniline (PANI) and procainamide (PROCA) was covalently linked to the PANI. The extracted human erythrocyte AChE formed a complex with the MNP@PANI-PROCA and an external magnet separated it from the undesired proteins. Finally, the enzyme was collected by increasing the ionic strength. Experimental Box-Behnken design was developed to optimize this process of human erythrocyte AChE purification protocol. The enzyme was purified in all fifteen experiments. However, the best AChE purification result was achieved, about 2000 times purified, when 100 mg of MNP@PANI-PROCA was incubated for one hour with 4 ml hemolysate extract. The SDS-PAGE of this preparation presented a molecular weight of approximately 70 kDa, corroborating with few previous studies of AChE from erythrocyte purification.


Subject(s)
Acetylcholinesterase , Erythrocytes , Magnetite Nanoparticles , Procainamide , Humans , Acetylcholinesterase/chemistry , Acetylcholinesterase/metabolism , Acetylcholinesterase/isolation & purification , Erythrocytes/enzymology , Magnetite Nanoparticles/chemistry , Procainamide/chemistry , Aniline Compounds/chemistry
5.
Cytokine ; 179: 156621, 2024 07.
Article in English | MEDLINE | ID: mdl-38648682

ABSTRACT

Chagas disease (CD) is caused by the hemoflagellate protozoan Trypanosoma cruzi. The control of the infection depends of the innate and acquired immune response of host. Moreover, CD plays a significant role in the immune response, and, in this context, microalgae can be an interesting alternative due to its immunomodulatory and trypanocidal effects. This study aimed to evaluate, in vitro, immunomodulatory potentials of the aqueous extracts of Chlorella vulgaris and Tetradesmus obliquus. Both microalgae extracts (ME) were obtained by sonication, and the selectivity index (SI) was determined by assays of inhibitory concentration (IC50) in T. cruzi trypomastigotes cells; as well as the cytotoxic concentrations (CC50) in human peripheral mononuclear cells (PBMC). The immune response was evaluated in T. cruzi-infected PBMC using the IC50 value. ME led to inhibition of T. cruzi trypomastigotes after 24 h of treatment, in which the IC50 values were 112.1 µg/ml to C. vulgaris and 15.8 µg ml-1 to T. obliquus. On the other hand, C. vulgaris did not affect the viability of PBMCs in concentrations up to 1000 µg ml-1, while T. obliquus was non-toxic to PBMCs in concentrations up to 253.44 µg ml-1. In addition, T. obliquus displayed a higher SI against T. cruzi (SI = 16.8), when compared with C. vulgaris (SI = 8.9). C. vulgaris decreased the levels of IFN, indicating a reduction of the inflammatory process; while T. obliquus displayed an interesting immunomodulatory effect, since discretely increased the levels of TNF and stimulated the production of the anti-inflammatory cytokine IL-10. This study confirms that ME are effective against T. cruzi trypomastigotes, and may able to control the parasitemia and preventing the progress of CD while regulating the inflammatory process.


Subject(s)
Chagas Disease , Leukocytes, Mononuclear , Microalgae , Trypanosoma cruzi , Trypanosoma cruzi/drug effects , Trypanosoma cruzi/immunology , Humans , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Chagas Disease/immunology , Chagas Disease/drug therapy , Chagas Disease/parasitology , Microalgae/chemistry , Plant Extracts/pharmacology , Cytokines/metabolism
6.
Brain Commun ; 6(2): fcae089, 2024.
Article in English | MEDLINE | ID: mdl-38529359

ABSTRACT

Leukoaraiosis is a neuroimaging marker of small-vessel disease that is characterized by high signal intensity on fluid-attenuated inversion recovery MRI. There is increasing evidence from pathology and neuroimaging suggesting that the structural abnormalities that characterize leukoaraiosis are actually present within regions of normal-appearing white matter, and that the underlying pathophysiology of white matter damage related to small-vessel disease involves blood-brain barrier damage. In this study, we aim to verify whether leukoaraiosis is associated with elevated signal intensity on fluid-attenuated inversion recovery imaging, a marker of brain tissue free-water accumulation, in normal-appearing white matter. We performed a cross-sectional study of adult patients admitted to our hospital with a diagnosis of acute ischaemic stroke or transient ischaemic attack. Leukoaraiosis was segmented using a semi-automated method involving manual outlining and signal thresholding. White matter regions were segmented based on the probabilistic tissue maps from the International Consortium for Brain Mapping 152 atlas. Also, normal-appearing white matter was further segmented based on voxel distance from leukoaraiosis borders, resulting in five normal-appearing white matter strata at increasing voxel distances from leukoaraiosis. The relationship between mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter and leukoaraiosis volume was studied in a multivariable statistical analysis using linear mixed modelling, having normal-appearing white matter strata as a clustering variable. One hundred consecutive patients meeting inclusion and exclusion criteria were selected for analysis (53% female, mean age 68 years). Mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was higher in the vicinity of leukoaraiosis and progressively lower at increasing distances from leukoaraiosis. In a multivariable analysis, the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was positively associated with leukoaraiosis volume and age (B = 0.025 for each leukoaraiosis quartile increase; 95% confidence interval 0.019-0.030). This association was found similarly across normal-appearing white matter strata. Voxel maps of the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter showed an increase in signal intensity that was not adjacent to leukoaraiosis regions. Our results show that normal-appearing white matter exhibits subtle signal intensity changes on fluid-attenuated inversion recovery imaging that are related to leukoaraiosis burden. These results suggest that diffuse free-water accumulation is likely related to the aetiopathogenic processes underlying the development of white matter damage related to small-vessel disease.

7.
Carbohydr Polym ; 334: 122061, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38553245

ABSTRACT

The galactomannan-based gel from Cassia grandis seeds was used to incorporate Penicillium sp. UCP 1286 and commercial collagenases. Experiments were carried out according to a 23-full factorial design to identify the most significant parameters for the incorporation process. The pH of the incorporation solution (pHi), stirring time (t), and initial protein concentration in the crude extract (PCi) were selected as the three independent variables, and the efficiency of collagenase incorporation (E) and collagenolytic activity (CA) after 360 min as the responses. pHi and PCi showed positive statistically significant effects on E, while CA was positively influenced by pHi and t, but negatively by PCi. The fungi collagenase was released from the gel following a pseudo-Fickian behavior. Additionally, no <76 % of collagenase was efficiently incorporated into the gel retaining a high CA (32.5-69.8 U/mL). The obtained results for the commercial collagenase (E = 93.88 %, CA = 65.8 U/mL, and n = 0.10) demonstrated a pseudo-Fickian behavior similar to the fungi-collagenase. The results confirm the biotechnological potential of the gel as an efficient matrix for the incorporation of catalytic compounds; additionally, the incorporation of collagenases was achieved by retaining the proteases CA and releasing them in a controlled manner.


Subject(s)
Cassia , Galactose/analogs & derivatives , Mannans , Cassia/chemistry , Collagenases/chemistry , Fungi/metabolism , Seeds/chemistry
8.
Rev. CEFAC ; 26(1): e3823, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1535107

ABSTRACT

ABSTRACT Purpose: to report scientific evidence on the impact of aphasia on central auditory processing and map the contribution of auditory training to aphasic individuals. Methods: a scoping review approaching national and international databases (SciELO, LILACS, PubMed, Scopus, and Cochrane Library) and the gray literature (Google Scholar and Open Grey). The inclusion criteria covered articles that addressed the interface between central auditory processing and aphasia, excluding duplicates, literature reviews, and scientific abstracts. Literature Review: the review comprised 13 articles that met the eligibility criteria for this study. Seven of the selected articles assessed central auditory processing, four used electrophysiological examinations (such as auditory brainstem response and long-latency auditory evoked potentials) to assess the auditory pathway, and only one analyzed the intervention in aphasic individuals with auditory training. Conclusion: scientific evidence points to an important change in aphasic people's central auditory processing, with impaired figure-ground, auditory closure, temporal resolution and ordering, and binaural integration. Moreover, it is relevant to assess auditory processing, given the contribution of auditory training in speech-language-hearing therapy for a better prognosis in the rehabilitation of aphasia.


RESUMO Objetivo: reportar as evidências científicas do impacto da afasia no Processamento Auditivo Central e mapear a contribuição do Treinamento Auditivo para a população afásica. Métodos: trata-se de uma revisão de escopo realizada nas bases de dados nacionais e internacionais: Scielo, Lilacs, Pubmed, Scopus, Cochrane Library e com uma busca adicional à literatura cinzenta no Google Scholar e Open Grey. Os critérios de inclusão abrangeram artigos que abordassem a interface do processamento auditivo central e afasia, excluindo-se as duplicações, artigos de revisão da literatura e resumos científicos. Revisão de Literatura: selecionaram-se 13 artigos que cumpriram os critérios de elegibilidade deste estudo. Dos artigos selecionados, sete apresentaram a avaliação do Processamento Auditivo Central, quatro apresentaram os exames eletrofisiológicos - como os exames de Potencial Evocado Auditivo de Tronco Encefálico (PEATE) e Potencial Evocado Auditivo de Longa Latência (PEALL) - para avaliação da via auditiva e apenas um estudo analisou a intervenção dos indivíduos afásicos por meio do treinamento auditivo. Conclusão: as evidências científicas apontam importante alteração no Processamento Auditivo Central dos afásicos, apresentando prejuízos nas habilidades auditivas de figura-fundo, fechamento auditivo, resolução e ordenação temporal e integração binaural. Ainda, demonstra-se como relevante a avaliação do processamento, devido à contribuição do Treinamento Auditivo nas terapias fonoaudiológicas para um melhor prognóstico na reabilitação das afasias.

9.
Immunobiology ; 229(1): 152779, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38118344

ABSTRACT

The therapeutic regimen for the treatment of American Tegumentary Leishmaniasis (ATL) is targeted at the death of the parasite; therefore, it is essential to develop a treatment that can act on the parasite, combined with the modulation of the inflammatory profile. Thus, the aim of this study was to make an in vitro evaluation of the therapeutic potential of Chlorella vulgaris extract (CV) and Imiquimod for ATL. Selectivity indices (SI) were determined by inhibitory concentration assays (IC50) in L. braziliensis cells and cytotoxic concentrations (CC50) were measured in human cells using the MTT method, based on the CV microalgae extract (IC50 concentrations of 15.63 to 500 µg/mL; CC50 concentrations of 62.5-1000 µg/mL) in comparison with the reference drugs and Imiquimod. The immune response was evaluated in healthy human cells by gene expression (RT-qPCR) and cytokine production (Flow Cytometry). The CV extract (SI = 6.89) indicated promising results by showing higher SI than meglumine antimoniate (SI = 3.44) (reference drug). In all analyses, CV presented a protective profile by stimulating the production of Th1 profile cytokines to a larger extent than the reference drugs. Imiquimod showed a high expression for Tbx21, GATA3, RORc and Foxp3 genes, with increased production only of the TNF cytokine. Therefore, the data highlight the natural extract and Imiquimod as strong therapeutic or adjuvant candidates against ATL, owing to modulation of immune response profiles, low toxicity in human cells and toxic action on the parasite.


Subject(s)
Antiprotozoal Agents , Chlorella vulgaris , Leishmania braziliensis , Leishmaniasis, Cutaneous , Humans , Imiquimod/therapeutic use , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Cytokines
10.
An Acad Bras Cienc ; 95(suppl 1): e20220552, 2023.
Article in English | MEDLINE | ID: mdl-37585969

ABSTRACT

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.


Subject(s)
Microalgae , Zea mays , Cost-Benefit Analysis , Fibrin , Hydrogen-Ion Concentration , Temperature
11.
Nat Prod Res ; : 1-7, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36661179

ABSTRACT

Due to the limitations of Chagas disease therapy, microalgae can be promising in the search of new trypanocidal compounds, since these organisms produce bioactive compounds with large pharmaceutical applications, including antiparasitic effects. In this work, trypanocidal activity of aqueous extract of Tetradesmus obliquus and, for the first time, aqueous extract of Chlorella vulgaris, were evaluated against trypomastigote forms of Trypanosoma cruzi. In addition, cytotoxic activity in Vero cells was evaluated. Our results showed that C. vulgaris and T. obliquus present trypanocidal activity (IC50 = 32.9 µg ml-1 and 36.4 µg ml-1, respectively), however, C. vulgaris did not present cytotoxic effects in Vero cells (CC50 > 600 µg ml-1) and displayed a higher selectivity against trypomastigotes forms of T. cruzi (SI > 18). Thus, microalgae extracts, such as aqueous extract of C. vulgaris, are promising potential candidates for the development of natural antichagasic drugs.

12.
Phys Chem Chem Phys ; 24(34): 20294-20302, 2022 Aug 31.
Article in English | MEDLINE | ID: mdl-35979742

ABSTRACT

Here, we report a computational investigation on the role of the most common van der Waals (vdW) corrections (D2, D3, D3(BJ), TS, TS+SCS, TS+HI, and dDsC) employed in density functional theory (DFT) calculations within local and semilocal exchange-correlation functionals to improve the description of the interaction between molecular species and solid surfaces. For this, we selected several molecular model systems, namely, the adsorption of small molecules (CH3, CH4, CO, CO2, H2O, and OH) on the close-packed Cu(111) surface, which bind via chemisorption or physisorption mechanisms. As expected, we found that the addition of the vdW corrections enhances the energetic stability of the Cu bulk in the face-centered cubic structure, which contributes to increasing the magnitude of the mechanical properties (elastic constants, bulk, Young, and shear modulus). Except for the TS+SCS correction, all vdW corrections substantially increase the surface energy, while the work function changes by about 0.05 eV (largest change). However, we found substantial differences among the vdW corrections when comparing its effects on interlayer spacing relaxations. Based on bulk and surface results, we selected only the D3 and dDsC vdW corrections for the study of the adsorption properties of the selected molecules on the Cu(111) surface. Overall, the addition of these vdW corrections has a greater effect on weakly interacting systems (CH4, CO2, H2O), while the chemisorption systems (CH3, CO, OH) are less affected.

13.
Rev. colomb. ciencias quim. farm ; 51(2)mayo-ago. 2022.
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1535853

ABSTRACT

Introdução: Os monoterpenos, que são os principais constituintes da maioria dos óleos essenciais, compreendem uma série ampla de substâncias naturais e/ou sintéticas que já apresentaram diversas atividades biológicas. Objetivo: O presente estudo teve como objetivo avaliar a atividade antibacteriana do monoterpeno (R)-(+)-citro nelal contra cepas de Pseudomonas aeruginosa. Metodologia: Utilizou-se a técnica de diluição seriada para a determinação da concentração inibitória mínima (CIM) e também realizou-se a determinação da concentração bactericida mínima (CBM) do (R)-(+)-citronelal. Resultados: Os resultados obtidos para o monoterpeno testado foi de CIM igual à 512 µg/mL, apresentando assim um efeito antibacteriano forte e CBM variação de 512 a 1024 µg/mL, sendo assim considerado bactericida. Conclusão: Conclui-se que o monoterpeno (R)-(+)-citronelal devido ao seu potencial antimicrobiano pode ser considerado muito importante para o tratamento de várias enfermidades causadas pela Pseudomonas aeruginosa.


SUMMARY Introduction: Monoterpenes, which are the main constituents of most essential oils, comprise a wide range of natural and/or synthetic substances that have already exhibited diverse biological activities. Objective: The present study aimed to evaluate the antibacterial activity of monoterpene (R)-(+)-citronellal against Pseudomonas aeruginosa strains. Methodology: The serial dilution technique was used to determine the Minimum Inhibitory Concentration (MIC) and the Minimal Bactericidal Concentration (CBM) of (R)-(+)-citronellal was also determined. Results: The results obtained for the tested monoterpene were MIC50 equal to 512 µg/mL, thus presenting a strong antibacterial effect and CBM ranging from 512 to 1024 µg/mL, thus being considered bactericidal. Conclusion : Thus, it is concluded that the monoterpene (R)-(+)-citronellal, due to its antimicrobial potential, can be considered very important for the treatment of several diseases caused by Pseudomonas aeruginosa.


Introducción: Los monoterpenos, que son los componentes principales de la mayoría de los aceites esenciales, comprenden una amplia gama de sustancias naturales o sintéticas que ya han exhibido diversas actividades biológicas. Objetivo: El presente estudio tuvo como objetivo evaluar la actividad antibacteriana del monoterpeno (R)-(+)-citronelal contra cepas de Pseudomonas aeruginosa. Metodología: Se utilizó la técnica de dilución en serie para determinar la Concentración Inhibitoria Mínima (MIC) y también se determinó la concentración bactericida mínima (CBM) de (R)-(+)-citronelal. Resultados: Los resultados obtenidos para el monoterpeno ensayado fueron MIC50 igual a 512 µg/mL, presentando así un fuerte efecto antibacteriano y CBM que van desde 512 a 1024 µg/mL, por lo que se considera bactericida. Conclusión: así, se concluye que el monoterpeno (R)-(+)-citronelal, por su potencial antimicrobiano, puede considerarse muy importante para el tratamiento de diversas enfermedades causadas por Pseudomonas aeruginosa.

14.
Biochimie ; 201: 63-74, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35839918

ABSTRACT

Photosynthetic microorganisms, specifically cyanobacteria and microalgae, can synthesize a vast array of biologically active molecules, such as lectins, that have great potential for various biotechnological and biomedical applications. However, since the structures of these proteins are not well established, likely due to the presence of intrinsically disordered regions, our ability to better understand their functionality is hampered. We embarked on a study of the carbohydrate recognition domain (CRD), intrinsically disordered regions (IDRs), amino acidic composition, as well as and functional motifs in lectins from cyanobacteria of the genus Arthrospira and microalgae Chlorella and Dunaliella genus using a combination of bioinformatics techniques. This search revealed the presence of five distinctive CRD types differently distributed between the genera. Most CRDs displayed a group-specific distribution, except to C. sorokiniana possessing distinctive CRD probably due to its specific lifestyle. We also found that all CRDs contain short IDRs. Bacterial lectin of Arthrospira prokarionte showed lower intrinsic disorder and proline content when compared to the lectins from the eukaryotic microalgae (Chlorella and Dunaliella). Among the important functions predicted in all lectins were several specific motifs, which directly interacts with proteins involved in the cell-cycle control and which may be used for pharmaceutical purposes. Since the aforementioned properties of each type of lectin were investigated in silico, they need experimental confirmation. The results of our study provide an overview of the distribution of CRD, IDRs, and functional motifs within lectin from the commercially important microalgae.


Subject(s)
Chlorella , Cyanobacteria , Carbohydrates , Chlorella/metabolism , Lectins/chemistry , Pharmaceutical Preparations , Proline
15.
Front Immunol ; 13: 891495, 2022.
Article in English | MEDLINE | ID: mdl-35844611

ABSTRACT

New therapeutic strategies for visceral leishmaniasis (VL) have been studied, and the development of an immunotherapeutic agent that modulates the host's immune response is necessary. The aim of this study was to evaluate in vitro the bioactive extracts of photosynthetic microorganisms (PMs) for their leishmanicidal/leishmanistatic and immunomodulatory potentials. Bioactive extracts from PMs (Arthrospira platensis and Dunaliella tertiolecta) were obtained by sonication. Reference drugs, miltefosine (MTF) and N-methylglucamine antimoniate (SbV), were also evaluated. The selectivity index (SI) of treatments was determined by assays of inhibitory concentration (IC50) in Leishmania infantum cells and cytotoxic concentrations (CC50) in human peripheral blood mononuclear cells by the MTT method. The immune response was evaluated in healthy human cells by the production of cytokines and nitric oxide (NO) and the gene expression of Tbx21, GATA3, RORc, and FOXP3, using four concentrations (CC50, ½ CC50, » CC50, and IC50) for in-vitro stimulation. Based on the data obtained, we observed that the extracts of D. tertiolecta (SI = 4.7) and A. platensis (SI = 3.8) presented better results when compared to SbV (SI = 2.1). When analyzing the immune response results, we identified that the extracts of PMs stimulated the production of cytokines of the Th1 profile more than the reference drugs. The extracts also demonstrated the ability to stimulate NO synthesis. Regarding gene expression, in all concentrations of A. platensis extracts, we found a balance between the Th1/Th2 profile, with the average expression of the Tbx21 gene more than the GATA3 in the highest concentration (CC50). Regarding the extract of D. tertiolecta, we can observe that, in the lowest concentrations, a balance between all the genes was present, with the average expression of the GATA3 gene being lower than the others. The best result was found in the ½ CC50 concentration, stimulating a balanced positive expression between the Th1×Th17×Treg profiles, with a negative expression of GATA3. Thus, PM extracts showed promising results, presenting low toxicity, leishmanicidal/leishmanistatic activity, and induction of the immune response, which could be potential therapeutic candidates for VL.


Subject(s)
Antiprotozoal Agents , Leishmaniasis, Visceral , Animals , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Cytokines/therapeutic use , Humans , Leukocytes, Mononuclear , Mice , Mice, Inbred BALB C
16.
An Acad Bras Cienc ; 94(2): e20201636, 2022.
Article in English | MEDLINE | ID: mdl-35319622

ABSTRACT

Hypertension is a factor that contributes to the risk of chronic diseases. The inhibition of angiotensin-I converting enzyme (ACE) is a useful therapeutic approach to the hypertension treatment. The algae have been an alternative for the production of ACE inhibitory (ACEi) peptides from enzymatic hydrolysis due to their protein-rich biomass. The aim of this study was to systematically review the literature regarding the production, composition and activity of ACEi peptides derived from algae proteins. Systematic database searches identified 648 related articles. Among these, only 14 were selected according to the eligibility criteria to this review. Macroalgae are more studied than microalgae as sources of ACEi peptides. Furthermore, hydrolysates by thermolysin or bromelain exhibited the highest ACEi activity compared to other enzymes. The main features of the peptides with high ACE inhibition are low molecular weight, short amino acids sequence and non-competitive inhibition pattern. In vivo studies using hydrolysates and peptides derived from algae proteins showed antihypertensive activity in spontaneously hypertensive rats (SHR). Thus, it is suggested that ACEi peptides derived from algae can be considered as potential antihypertensive.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors , Hypertension , Angiotensin-Converting Enzyme Inhibitors/chemistry , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Angiotensins/therapeutic use , Animals , Antihypertensive Agents/chemistry , Antihypertensive Agents/pharmacology , Antihypertensive Agents/therapeutic use , Hypertension/drug therapy , Peptides/pharmacology , Rats
17.
Appl Microbiol Biotechnol ; 106(2): 497-504, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34985569

ABSTRACT

Wounds are a public health problem due to long periods required to repair damaged skin, risk of infection, and amputations. Thus, there is a need to obtain new therapeutic agents with less side effects, more effective oxygen delivery, and increased epithelial cell migration. Photosynthetic microorganisms, such as microalgae and cyanobacteria, may be used as a source of biomolecules for the treatment of different injuries. The aim of this review article focuses on healing potential using phytoconstituents from photosynthetic microorganisms. Cyanophyte Spirulina and Chlorophyte Chlorella are more promising due to steroids, triterpenes, carbohydrates, phenols, and proteins such as lectins and phycocyanin. However, there are few reports about identification and specific function of these molecules on the skin. In other microalgae and cyanobacteria genus, high contents of pigments such as ß-carotene, chlorophyll a, allophycocyanin, and hydroxypheophytin were detected, but their effects on phases of wound healing is absent yet. The development of new topical drugs from photosynthetic microorganisms could be a potential alternative to maximize healing. KEY POINTS: • Conventional treatment to skin injuries has limitations. • Proteins, terpenes, and phenols increase collagen deposition and re-epithelialization. • Microalgae and cyanobacteria may be used as a source of biomolecules to wound healing.


Subject(s)
Chlorella , Microalgae , Chlorophyll A , Collagen , Photosynthesis
18.
ACS Chem Biol ; 16(11): 2057-2067, 2021 11 19.
Article in English | MEDLINE | ID: mdl-34597512

ABSTRACT

Arthrospira, a genus of blue-green cyanobacteria, is known for its great biological activity due to the presence of a large number of substances that are potentially active against tumor cells. This review aimed to evaluate the potential of Arthrospira spp. for the treatment or reduction of several types of cancer, in addition to elucidating the mechanism of action by which their compounds act on tumor cells. A systematic review was carried out in PubMed, Science Direct, LILACS, and SciELO databases, including original studies from 2009 to 2020. A total of 1306 articles were independently assessed according to the eligibility criteria, of which 20 articles were selected and assessed for the risk of bias using seven criteria developed by the authors. Arthrospira spp. of cyanobacteria have been evaluated against eight different types of cancer, mainly colon cancer. Among all the compounds, phycocyanin was the most used, followed by peptides and photosensitizers. In general, compounds from Arthrospira spp. act as anticancer agents by inhibiting the proliferation of tumor cells, triggering cell cycle arrest, and inducing apoptosis via different signaling pathways. In addition, these compounds also exhibited antioxidant, antiangiogenic, and antimetastatic activities. Phycocyanin demonstrated better efficacy against several types of cancer via different activities and therapeutic targets. Furthermore, it was the only molecule that functioned in synergy with other drugs that are already well established for the treatment of cancer.


Subject(s)
Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy , Spirulina/chemistry , Animals , Apoptosis/drug effects , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Phycocyanin/therapeutic use
19.
J Ophthalmic Vis Res ; 16(3): 320-324, 2021.
Article in English | MEDLINE | ID: mdl-34394860

ABSTRACT

PURPOSE: To validate the standard values and evaluate the success rate in the treatment of minor and major trichiasis using thermoablation with a diode green laser. METHODS: In this interventional prospective study, individuals with minor or major trichiasis who were treated with thermoablation using diode green laser were included. The patients' mean age was 72.1 years; the majority were females (54.1%) and Caucasian (98%). The parameters of the diode laser were wavelength of 532 nm, application time of 200 ms, target size of 50 µm, interval between the shots 150 to 200 ms, and power of 600 to 750 mW. The number of shots was defined by the depth of ablation sufficient to reach the pilus hair bulb. The patients were evaluated by slit-lamp every 3 to 4 months, for up to 15 months. The treatment success rate and the association between variables were analyzed. RESULTS: The study sample was comprised of 98 patients with 135 affected lids and 337 lashes with trichiasis. Minor trichiasis (91.8%), unilateral trichiasis (67.3%), trichiasis affecting the lower eyelid (85.9%), and trichiasis resulting from blepharitis (64.3%) were the most common presentation profiles. The overall cure rate at the end of the study was 85%, with 69% being cured with a single session and 82.8% with two treatment sessions. CONCLUSION: Thermoablation using a diode green laser applying the specified parameters to treat minor and major trichiasis is effective and results in high cure rate.

20.
Phys Chem Chem Phys ; 23(32): 17553-17566, 2021 Aug 28.
Article in English | MEDLINE | ID: mdl-34369523

ABSTRACT

The adsorption of alcohols on transition-metal (TM) substrates has received the attention of many researchers due to the applications of alcohols in several technological fields. However, our atomic-level understanding is still far from satisfactory, in particular for the interaction of alcohols with finite-size TM clusters, where new effects can arise due to the presence of quantum-size effects. In this work, we report a theoretical investigation of the adsorption properties of methanol, ethanol, and ethylene glycol on 12 different 3d, 4d, and 5d TM15 clusters based on density functional theory calculations within the semi-empirical D3 van der Waals corrections. From the correlation analysis of all the lowest- and high-energy configurations, we identified the adsorption modes of methanol, ethanol, and ethylene glycol on the TM15 clusters, in which the OH group binds to the cationic TM sites via the O-TM and H-TM interactions. Due to the relatively weak alcohol-TM15 interaction, the changes induced on the TM15 clusters are small, except for Au15 and Ru15, where the bare cluster changes its structure to a nearby minimum in the potential energy surface. The adsorption energy for the alcohol/TM15 systems is correlated to the combination of several parameters, in which the main contribution is connected with the O-TM interaction and the HOTM angles. Furthermore, the TM electronegativity is an important descriptor for the methanol and ethanol adsorption energies, while charge transfer is important for ethylene glycol.

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