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1.
Biomed Pharmacother ; 170: 115979, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061138

RESUMO

Lung cancer is one of the leading causes of cancer-related deaths in men and women worldwide. Current treatments have limited efficacy, cause significant side effects, and cells can develop drug resistance. New therapeutic strategies are needed to discover alternative anticancer agents with high efficacy and low-toxicity. TMBP, a biphenyl obtained by laccase-biotransformation of 2,6-dimethoxyphenol, possesses antitumor activity against A549 adenocarcinoma cells. Without causing damage to sheep erythrocytes and mouse peritoneal macrophages of BALB/c mice. In addition to being classified as a good oral drug according to in-silico studies. This study evaluated the in-vitro cytotoxic effect of TMBP on lung-cancer cell-line NCI-H460 and reports mechanisms on immunomodulation and cell death. TMBP treatment (12.5-200 µM) inhibited cell proliferation at 24, 48, and 72 h. After 24-h treatment, TMBP at IC50 (154 µM) induced various morphological and ultrastructural changes in NCI-H460, reduced migration and immunofluorescence staining of N-cadherin and ß-catenin, induced increased reactive oxygen species and nitric oxide with reduced superoxide radical-anion, increased superoxide dismutase activity and reduced glutathione reductase. Treatment also caused metabolic stress, reduced glucose-uptake, intracellular lactate dehydrogenase and lactate levels, mitochondrial depolarization, increased lipid droplets, and autophagic vacuoles. TMBP induced cell-cycle arrest in the G2/M phase, death by apoptosis, increased caspase-3/7, and reduced STAT-3 immunofluorescence staining. The anticancer effect was accompanied by decreasing PI3K, AKT, ARG-1, and NF-κB levels, and increasing iNOS. These results suggest its potential as a candidate for use in future lung anticancer drug design studies.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Feminino , Humanos , Animais , Camundongos , Ovinos , Neoplasias Pulmonares/patologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proliferação de Células , Estresse Oxidativo , Estresse Fisiológico
2.
Sci Rep ; 13(1): 6928, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37117253

RESUMO

Available treatments for leishmaniasis have been widely used since the 1940s but come at a high cost, variable efficacy, high toxicity, and adverse side-effects. 3,3',5,5'-Tetramethoxy-biphenyl-4,4'-diol (TMBP) was synthesized through laccase-catalysis of 2,6-dimethoxyphenol and displayed antioxidant and anticancer activity, and is considered a potential drug candidate. Thus, this study aimed to evaluate the anti-leishmanial effect of TMBP against promastigote and amastigote forms of Leishmania (L.) amazonensis and investigated the mechanisms involved in parasite death. TMBP treatment inhibited the proliferation (IC50 0.62-0.86 µM) and induced the death of promastigote forms by generating reactive oxygen species and mitochondrial dysfunction. In intracellular amastigotes, TMBP reduced the percentage of infected macrophages, being 62.7 times more selective to the parasite (CC50 53.93 µM). TMBP did not hemolyze sheep erythrocytes; indicative of low cytotoxicity. Additionally, molecular docking analysis on two enzyme targets of L. amazonensis: trypanothione reductase (TR) and leishmanolysin (Gp63), suggested that the hydroxyl group could be a pharmacophoric group due to its binding affinity by hydrogen bonds with residues at the active site of both enzymes. TMBP was more selective to the Gp63 target than TR. This is the first report that TMBP is a promising compound to act as an anti-leishmanial agent.


Assuntos
Antiprotozoários , Leishmania mexicana , Leishmania , Animais , Ovinos , Camundongos , Simulação de Acoplamento Molecular , Antiprotozoários/farmacologia , Antiprotozoários/química , Camundongos Endogâmicos BALB C
3.
Cell Biochem Funct ; 40(7): 773-783, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36111697

RESUMO

Obesity is associated with other diseases such as diabetes and cancer. Botryosphaeran, a fungal (1→3)(1→6)-ß-d-glucan, is described to present antimutagenic, hypoglycemic, hypocholesterolemic, and antitumor activities when administered by gavage over 15 days in rats and mice. Thus, the present study aims to analyze the metabolic effects of Botryosphaeran (12 mg/kg body weight/day) treatment over 30 days in obese Wistar male rats. Obesity was induced in the rats by a high-fat/high-sugar diet for 8 weeks. Control rats received a standard diet. On the 5th week, Botryosphaeran treatment commenced. Groups: control, obese, and obese+Botryosphaeran 30 days. In the 8th week, obesity was characterized. Feed intake, glucose and lipid profiles, glucose tolerance, and insulin sensitivity were analyzed. Obese rats showed accumulation of visceral adipose tissue, reduction of muscle mass, glucose intolerance, insulin resistance, hyperglycemia, and dyslipidemia. Botryosphaeran effectively reduced weight gains and the accumulation of retroperitoneal adipose tissue, corrected the levels of glucose, triglycerides, and very low-density lipoprotein-cholestrol, and improved insulin sensitivity. Treatment for 30 days was effective in maintaining the beneficial effects demonstrated by this ß-glucan when administered for 15 days without promoting side effects. Treatment with (1→3)(1→6)-ß- d-glucan presented anti-obesogenic and beneficial metabolic effects in Wistar rats; important for the treatment of obesity and its comorbidities.


Assuntos
Resistência à Insulina , beta-Glucanas , Animais , Glicemia , Dieta Hiperlipídica , Glucanos/farmacologia , Glucose , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Insulina , Lipoproteínas LDL , Masculino , Camundongos , Obesidade/metabolismo , Ratos , Ratos Wistar , Açúcares , Triglicerídeos/metabolismo , beta-Glucanas/farmacologia
4.
Biomacromolecules ; 23(10): 4041-4052, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36173245

RESUMO

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-ß-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Antivirais/farmacologia , Glucanos/farmacologia , Herpes Simples/tratamento farmacológico , Humanos
5.
Cell Biochem Funct ; 40(6): 578-588, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35788958

RESUMO

Several biological activities of the fungal exopolysaccharide (1 → 3)(1 → 6)-ß-d-glucan (botryosphaeran) have been described in the literature, but its effects on inflammation have not been evaluated. This study aimed to investigate the action of botryosphaeran on experimental mice models of carrageenan-induced acute pleurisy and acute paw edema, and complete Freund's adjuvant-induced persistent paw edema. All botryosphaeran doses tested (1.0, 2.5, 5.0, and 10.0 mg/kg birth weight [b.w.], orally administered) reduced leukocyte recruitment, nitric oxide (NO) levels, and protein extravasation in the pleural cavity. Botryosphaeran (5 mg/kg b.w.) did not diminish edema and mechanical hyperalgesia in the paw within 4 h; however, cold allodynia was alleviated within the first 2 h. In the persistent paw inflammation model, the effects of daily oral administration of botryosphaeran (5 mg/kg b.w.) were evaluated over 3 and 7 days. The fungal ß-glucan significantly reduced the levels of the cytokines, tumor necrosis factor(TNF)-α, interleukin (IL)-6), and IL-10, in the paw homogenates in both protocols, while paw edema and the levels of advanced oxidation protein products (AOPP) only diminished on Day 7. No effect in mechanical hyperalgesia was observed. Oral treatment for 3 or 7 days also decreased the plasma levels of NO, AOPP, TNF-α, and IL-10. On Day 7, the number of leukocytes in the blood was also reduced by this treatment. Importantly, botryosphaeran did not induce inflammation in mice when administered alone over 7 days. This study demonstrated the anti-inflammatory and antinociceptive potential of botryosphaeran in these experimental models, making this fungal ß-glucan a new possibility for complementary treating acute and chronic inflammation.


Assuntos
Hiperalgesia , beta-Glucanas , Administração Oral , Produtos da Oxidação Avançada de Proteínas/metabolismo , Animais , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/patologia , Glucanos/efeitos adversos , Glucanos/farmacologia , Glucanos/uso terapêutico , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-10 , Leucócitos/patologia , Camundongos , Nociceptividade , beta-Glucanas/efeitos adversos , beta-Glucanas/farmacologia , beta-Glucanas/uso terapêutico
6.
J Toxicol Environ Health A ; 85(13): 521-537, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35255775

RESUMO

Breast cancer is the most common cancer worldwide among the female population. The fungal exopolysaccharide botryosphaeran is a (1→3)(1→6)-ß-D-glucan with limited solubility in water that can be promoted through carboxymethylation. Thus, the aim of this study was to examine in-vitro anticancer effects of carboxymethylated-botryosphaeran (CM-BOT) on breast cancer MCF-7 cells cultivated in multicellular tumor spheroids (MCTS). CM-BOT (≥ 600 µ/ml) decreased the viability (resazurin assay) of MCF-7 grown in monolayers after 24 hr incubation. Although CM-BOT did not markedly alter viability of MCTS in the resazurin assay after 24, 48 or 72 hr, CM-BOT ≥ 600 µg/ml produced cell-death by apoptosis after 72 hr utilizing the triple staining assay and labeling dead cells with propidium iodide, which can also be visualized on the architecture of MCTS. CM-BOT (1000 µg/ml) inhibited cell proliferation, which resulted in MCTSs with smaller diameters than controls. CM-BOT at all concentrations examined decreased the ability of MCF-7 to form colonies and to migrate in the extracellular matrix. This is the first report using MCTS-architecture to study anti-tumor effects of ß-glucans. Our findings are important in the search for compounds for use in breast cancer therapy, or as adjuvants in reducing the adverse effects of mammary tumor chemotherapy.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Feminino , Glucanos/farmacologia , Glucanos/uso terapêutico , Humanos , Células MCF-7 , Esferoides Celulares
7.
Appl Biochem Biotechnol ; 194(10): 4348-4361, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35146637

RESUMO

The oxidation process of 2,6-dimethoxyphenol (2,6-DMP) by laccase from Botryosphaeria rhodina MAMB-05 and the corresponding enzyme-mediator systems was studied using cyclic voltammetry (CV). The enzyme was classified as a high oxidation potential laccase (> 0.70) V vs. NHE) based on its Redox potential at different pHs. The cyclic voltammograms for 2,6-DMP (- 58.7 mV pH-1) showed that its oxidation potential decreased more significantly compared to the enzyme (- 50.2 mV pH-1) by varying the pH. The 2,2'-azino-bis[3-ethyl-benzothiazoline-6-sulfonic acid] diammonium salt (ABTS) and 2,2,6,6-tetramethylpiperidine 1-oxyl radical (TEMPO) mediators were effectively oxidized by laccase from B. rhodina MAMB-05. The influence of laccase on the comproportionation of ABTS and the ionic step of the oxidation of TEMPO was also studied using CV. A higher potential difference was observed between laccase and the substrate, and correlated with higher enzyme activity. For the laccase-mediator systems, there was no clear correlation of potential difference between laccase and mediators with enzyme activity towards 2,6-DMP. This observation suggests that there are other limiting parameters for enzyme activity despite Redox potential difference, especially during ionic steps of the mechanism.


Assuntos
Elétrons , Lacase , Benzotiazóis , Catálise , Lacase/metabolismo , Oxirredução , Pirogalol/análogos & derivados , Ácidos Sulfônicos
8.
Chem Biol Interact ; 351: 109713, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34699765

RESUMO

Leishmaniasis is an infectious-parasitic disease caused by the protozoan Leishmania spp. The available treatments are based upon expensive drugs bearing adverse side-effects. The search for new therapeutic alternatives that present a more effective action without causing adverse effects to the patient is therefore important. The objective of this study was to evaluate the in vitro effect of botryosphaeran, a (1 â†’ 3)(1 â†’ 6)-ß-D-glucan, on the promastigote and intracellular amastigote forms of Leishmania amazonensis. The direct activity of botryosphaeran on promastigote forms was evaluated in vitro and inhibited proliferation, the IC50 7 µg/mL in 48 h was calculated. After 48 h treatment, botryosphaeran induced nitric oxide production (NO), caused mitochondrial membrane hyperpolarization, increased reactive oxygen species (ROS), and accumulation of lipid vesicles in promastigotes, resulting in apoptosis, necrosis and autophagy, and was accompanied by morphological and ultrastructural changes. The range of concentrations used did not alter the viability of peritoneal macrophages from BALB/c mice and erythrocytes of sheep. Botryosphaeran was able to reduce the number of infected macrophages and the number of amastigotes per macrophage at 12.5 µg/mL (50.75% ± 6.48), 25 µg/mL (55.66% ± 3.93) and 50 µg/mL (72.9% ± 6.98), and IC50 9.3 µg/mL (±0.66) for intracellular amastigotes forms. The leishmanicidal effect was due to activation of NF-κB and promoted an increase in pro-inflammatory cytokines (TNF-α and IL-6), iNOS and microbial-derived ROS and NO, in addition to decreasing the levels of SOD. Based upon the data obtained, we infer that botryosphaeran exerted an active leishmanicidal and immunomodulatory effect, acting on promastigotes through autophagic, apoptotic and necrosis processes, and in the intracellular amastigote form, through the action of ROS and NO.


Assuntos
Apoptose/efeitos dos fármacos , Glucanos/farmacologia , Fatores Imunológicos/farmacologia , Leishmania/efeitos dos fármacos , NF-kappa B/metabolismo , Tripanossomicidas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Interleucina-6/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/microbiologia , Masculino , Camundongos Endogâmicos BALB C , Necrose/induzido quimicamente , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34681671

RESUMO

The infection of mammalian cells by enveloped viruses is triggered by the interaction of viral envelope glycoproteins with the glycosaminoglycan, heparan sulfate. By mimicking this carbohydrate, some anionic polysaccharides can block this interaction and inhibit viral entry and infection. As heparan sulfate carries both carboxyl and sulfate groups, this work focused on the derivatization of a (1→3)(1→6)-ß-D-glucan, botryosphaeran, with these negatively-charged groups in an attempt to improve its antiviral activity. Carboxyl and sulfonate groups were introduced by carboxymethylation and sulfonylation reactions, respectively. Three derivatives with the same degree of carboxymethylation (0.9) and different degrees of sulfonation (0.1; 0.2; 0.4) were obtained. All derivatives were chemically characterized and evaluated for their antiviral activity against herpes (HSV-1, strains KOS and AR) and dengue (DENV-2) viruses. Carboxymethylated botryosphaeran did not inhibit the viruses, while all sulfonated-carboxymethylated derivatives were able to inhibit HSV-1. DENV-2 was inhibited only by one of these derivatives with an intermediate degree of sulfonation (0.2), demonstrating that the dengue virus is more resistant to anionic ß-D-glucans than the Herpes simplex virus. By comparison with a previous study on the antiviral activity of sulfonated botryosphaerans, we conclude that the presence of carboxymethyl groups might have a detrimental effect on antiviral activity.


Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Herpesviridae/efeitos dos fármacos , Ácidos Sulfônicos/química , beta-Glucanas/química , Animais , Antivirais/química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Vírus da Dengue/fisiologia , Glucanos/química , Glucanos/farmacologia , Herpesviridae/fisiologia , Metilação , Células Vero , Internalização do Vírus/efeitos dos fármacos , beta-Glucanas/farmacologia
10.
J Hazard Mater ; 420: 126598, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34274805

RESUMO

Two biomass types of Botryosphaeria rhodina MAMB-05 (VMSM and M3) were evaluated to determine their effectiveness in removing Ag(I) ions from synthetic solutions. Both biomass types obtained good results in the biosorption process with maximum biosorption capacities (qm) for the Langmuir model of 34.67 and 39.23 mg Ag(I)/g dry biomass for M3 and VMSM, respectively. The biomass was characterized by X-ray microfluorescence and Fourier-transform-infrared spectroscopy (FT-IR). After the biosorption process, the mechanisms involved in biosorption were studied by FT-IR, X-ray diffraction (XRD), Field Emission Scanning Microscopy/Energy Dispersive X-ray Analysis (FESEM/EDX) and Ultraviolet-Visible Spectrophotometry. The results demonstrated the participation of various mechanisms in the retention of silver on biomass (bioadsorption, complexation, ion exchange, covalent bonding) that resulted in the formation of silver chloride nanoparticles (AgCl-NPs) and silver nanoparticles (AgNPs). The sizes of AgCl-NPs (chlorargyrite) according to the Debye-Scherrer equation were 19.29 nm (VMSM biomass) and 24.9 nm for the M3 type. For AgNPs the crystal size was between 1.5 and 0.8 nm for VMSM and M3 respectively. Furthermore, it was found that an undetermined fraction of the silver nanoparticles after biosorption remained in solution, which could be advantageous for their recovery.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos , Ascomicetos , Biomassa , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
Int J Biol Macromol ; 183: 316-330, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33930443

RESUMO

A hydrogel containing exocellular (1 → 6)-ß-D-glucan (lasiodiplodan, LAS) was developed and its wound healing potential was evaluated. ß-Glucans have attracted much interest by the cosmetic industry sector because of their bioactive and functional properties and in promoting skin health. In the present work an ß-glucan was studied as a healing biomaterial that has not hitherto been reported in the scientific literature. LAS produced by the ascomycete Lasiodiplodia theobromae MMPI was used in the formulation of a healing hydrogel. Physicochemical and microbiological quality parameters, antioxidant potential and stability of the formulation was evaluated. FTIR, thermal analysis and SEM techniques were also employed in the characterization. Wistar rats were used as a biological model to investigate the wound healing potential. Histological analyses of cutaneous tissue from the dorsal region were conducted after 4, 7, 10 and 14 days of treatment, and evaluated re-epithelialization, cell proliferation and collagen production. Physicochemical stability, microbiological quality and antioxidant potential, especially in relation to its ability to scavenge hydroxyl radicals were found. The hydrogel stimulated cell re-epithelialization and proliferation during all days of the treatment, and stimulated an increase of collagen fibers. Lasiodiplodan showed immunomodulatory activity in wound healing and this biomacromolecule could be an alternative compound in wound care.


Assuntos
Colágeno/química , Glucanos/química , Hidrogéis/química , Hidrogéis/farmacologia , Polissacarídeos/química , Cicatrização/efeitos dos fármacos , Animais , Ratos
12.
Int J Biol Macromol ; 177: 176-203, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33609583

RESUMO

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Factors increasing the risks for CVD development are related to obesity, diabetes, high blood cholesterol, high blood pressure and lifestyle. CVD risk factors may be treated with appropriate drugs, but prolonged can use cause undesirable side-effects. Among the natural products used in complementary and alternative medicines, are the ß-ᴅ-glucans; biopolymers found in foods (cereals, mushrooms), and can easily be produced by microbial fermentation. Independent of source, ß-glucans of the mixed-linked types [(1 → 3)(1 → 6)-ß-ᴅ-glucans - fungal, and (1 → 3)(1 → 4)-ß-ᴅ-glucans - cereal] have widely been studied because of their biological activities, and have demonstrated cardiovascular protective effects. In this review, we discuss the roles of ß-ᴅ-glucans in various pathophysiological conditions that lead to CVDs including obesity, dyslipidemia, hyperglycemia, oxidative stress, hypertension, atherosclerosis and stroke. The ß-glucans from all of the sources cited demonstrated potential hypoglycemic, hypocholesterolemic and anti-obesogenicity activities, reduced hypertension and ameliorated the atherosclerosis condition. More recently, ß-glucans are recognized as possessing prebiotic properties that modulate the gut microbiome and impact on the health benefits including cardiovascular. Overall, all the studies investigated unequivocally demonstrated the dietary benefits of consuming ß-glucans regardless of source, thus constituting a promising panaceutical approach to reduce CVD risk factors.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , beta-Glucanas/farmacologia , beta-Glucanas/uso terapêutico , Animais , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Anticolesterolemiantes/farmacologia , Anticolesterolemiantes/uso terapêutico , Fermentação/efeitos dos fármacos , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico
13.
Mikrochim Acta ; 188(1): 28, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33404780

RESUMO

A photoelectrochemical biosensing strategy for the highly sensitive detection of the flavonoid rutin was developed by synergizing the photoelectrocatalytic properties of hematite (α-Fe2O3) decorated with palladium nanoparticles (PdNPs) and the biocatalysis towards laccase-based reactions. The integration of α-Fe2O3.PdNPs with a polyphenol oxidase as a biorecognition element yields a novel biosensing platform. Under visible light irradiation, the photoactive biocomposite can generate a stable photocurrent, which was found to be directly dependent upon the concentration of rutin. Under the optimal experimental conditions, the cathodic photocurrent, measured at 0.33 V vs. Ag/AgCl, from the square-wave voltammograms presented a linear dependence on the rutin concentration within the range of 0.008-30.0 × 10-8 mol L-1 (sensitivity: 1.7 µA·(× 10-8 M-1)·cm-2), with an experimental detection limit (S/N = 3) of 8.4 × 10-11 mol L-1. The proposed biosensor device presented good selectivity towards rutin in the presence of various organic compounds and inorganic ions, demonstrating the potential application of this biosensing platform in complex matrices. This bioanalytical device also exhibited excellent operational and analytical properties, such as intra-day (standard deviation, SD = 0.21%) and inter-day (SD = 1.30%) repeatability, and long storage stability (SD = 2.80% over 30 days).Graphical abstract.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Compostos Férricos/química , Rutina/urina , Adulto , Enzimas Imobilizadas/química , Compostos Férricos/efeitos da radiação , Humanos , Lacase/química , Luz , Limite de Detecção , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Paládio/química , Paládio/efeitos da radiação , Processos Fotoquímicos , Chá/química , Vinho/análise , Adulto Jovem
14.
Nutr Cancer ; 73(7): 1175-1192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32643421

RESUMO

Studies demonstrate that obesity can increase tumor development. Botryosphaeran, a fungal (1→3)(1→6)-ß-D-glucan, presents antimutagenic, antiproliferative and pro-apoptotic activities. This study evaluated the effects of botryosphaeran on tumor development and metabolic and hematological parameters in tumor-bearing obese and non-obese rats. Obesity was induced by a high-fat and high-sugar diet, while control rats received standard diet and water without sugar for 10 weeks. On 8th-week, Walker-256 tumor cells were inoculated in the rats, and treatment with botryosphaeran (12 mg/Kg b.w.) started. Groups:control tumor-CT, control tumor botryosphaeran-CTB, obese tumor-OT and obese tumor botryosphaeran-OTB. On 10th-week, tumor development, cachexia, metabolic and hematological parameters were analyzed. Tumor development and cachexia were significantly higher in the OT group compared to the CT group, and botryosphaeran attenuated these parameters. OT rats presented accumulation of adipose tissue, reduced muscle mass, glucose intolerance, insulin resistance, hyperglycemia, anemia, leukocytosis, and thrombocytopenia. Botryosphaeran corrected insulin resistance and hyperglycemia, modulated cholesterol levels, and increased leukocyte and lymphocytes in obese rats, which can be attributable to an inflammatory response against the Walker-256 tumor, contributing to a lower tumor development. Our data demonstrated that botryosphaeran was effective in attenuating tumor growth and in improving the metabolic and hematological profiles of the tumor-bearing rats, demonstrating its potential role in the cancer's management.


Assuntos
Caquexia , Neoplasias , Animais , Caquexia/etiologia , Caquexia/prevenção & controle , Glucanos , Obesidade/complicações , Ratos , Ratos Wistar
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 249: 119255, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33338938

RESUMO

Surface-enhanced Raman spectroscopy (SERS) became a useful analytical technique with the development of appropriate metallic substrates. The need for SERS substrates that immobilize metallic nanoparticles prompted this work to search for an appropriate material. This work presents the preparation, characterization and application of a SERS substrate for crystal violet (CV) detection, as the probe molecule. The inner layer of the substrate is a thin film of the fungal ß-D-glucan, botryosphaeran, covered by a thin layer of silver nanoparticles (AgNPs). The nanoparticles were produced by laser ablation, a fast and clean method for their preparation, and the layers were assembled by casting. Scanning electron and atomic force microscopies, UV-VIS and Raman spectroscopy and X-ray diffraction allowed the characterization of the surface of the substrate. Analysis by Raman spectroscopy showed promising results for SERS amplification on the substrate. Detection of CV reached enhancement factors up to 106 orders of magnitude, compared to normal Raman spectra. Linearity was observed for analyses on the SERS substrate at concentration ranges of 0.005 to 1 µmol L-1. The assembly reached the detection of 12 pmol cm-2 of CV, which corresponds to 96 fg of the probe molecule contained in the area of the substrate effectively interacting with the laser. The substrate was more efficient than silver colloids to perform SERS.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Violeta Genciana , Polissacarídeos , Prata
16.
Int J Biol Macromol ; 165(Pt A): 985-994, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32991890

RESUMO

Obesity is an important risk factor in tumor development. Botryosphaeran, a (1 â†’ 3)(1 â†’ 6)-ß-D-glucan, produced by the fungus Botryosphaeria rhodina (MAMB-05), is a high molecular mass, water-soluble exopolysaccharide. It consists of a main chain of (1 â†’ 3)-linked ß-d-glucose units, with a degree of branching of ~22% at carbon-6 with glucose and gentiobiose residues linked through ß-(1 â†’ 6)-bonds, and presents a triple helix conformation. Botryosphaeran presents anticlastogenic, antiproliferative, pro-apoptotic and anti-obesogenic activities. This study evaluated the effects of botryosphaeran on tumor development in obesity and analyzed its mechanism of action. Obesity was induced in male Wistar rats by a high-fat/high-sugar diet. After 9 weeks, rats were divided into two groups: Obese Tumor (OT) and Obese Tumor Botryosphaeran (OTB), and inoculated with 1 × 107 Walker-256 tumor cells, and treatment with botryosphaeran (30 mg/kg b.w./day via gavage for 15 days) commenced. On the 11th week, biological parameters, tumor development, metabolic profile, erythrogram and protein expression were evaluated. Botryosphaeran significantly reduced tumor growth, body-weight loss and cachexia. Furthermore, botryosphaeran decreased mesenteric fat and insulin resistance, corrected macrocytic anemia, and increased Forkhead transcription factor-3a (FOXO3a) activity. Our study demonstrated the potential role of botryosphaeran in the management of cancer in tumor-bearing obese rats by increasing insulin sensitivity and FOXO3a activity.


Assuntos
Caquexia/tratamento farmacológico , Glucanos/farmacologia , Neoplasias/tratamento farmacológico , Obesidade/tratamento farmacológico , Animais , Ascomicetos/química , Caquexia/etiologia , Caquexia/genética , Caquexia/patologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Proteína Forkhead Box O3/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucanos/química , Glucose/metabolismo , Humanos , Insulina/genética , Resistência à Insulina/genética , Masculino , Neoplasias/etiologia , Neoplasias/genética , Neoplasias/patologia , Obesidade/complicações , Obesidade/genética , Obesidade/patologia , Ratos
17.
Bioelectrochemistry ; 135: 107543, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32450282

RESUMO

Laccase from Botryosphaeria rhodina MAMB-05 was covalently immobilized on carboxymethyl-botryosphaeran by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide (EDC/NHS) in aqueous solution. This approach was employed to fabricate a novel laccase-based biosensor to electrochemically quantify quercetin (QCT), using a simple carbon black paste electrode as a transducer. The proposed biosensor was characterized by electrochemical impedance spectroscopy and Nyquist plots were used to evaluate the immobilization of the enzyme. For determining QCT, variables were optimized, that included experimental conditions for laccase immobilization, pH of the supporting electrolyte, and instrumental parameters of the electroanalytical technique. From square-wave-voltammograms, a linear dependence between the cathodic current peak and QCT concentration was observed within the range 4.98-50.0 × 10-8 mol L-1, with a theoretical detection limit of 2.6 × 10-8 mol L-1. The proposed method was successfully applied to determine QCT in beverages, pharmaceuticals, and biological samples. The proposed biosensor device presented good selectivity in the presence of uric acid, various inorganic ions, as well as other phenolic compounds, demonstrating the potential application of this biosensing platform in chemically complex solutions. Operational and analytical stability of the laccase-biosensor were evaluated, and good intra-day (SD = 1.23%) and inter-day (SD = 2.32%) repeatability, and long storage stability (SD = 3.47%) are presented.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas/métodos , Glucanos/química , Lacase/química , Quercetina/análise , Limite de Detecção , Soluções , Água/química
18.
Life Sci ; 252: 117608, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32289434

RESUMO

AIMS: Cancer is a multifactorial disease characterized by an uncontrolled growth of cells that can lead to cachexia-anorexia syndrome. Botryosphaeran, a fungal (1 â†’ 3)(1 â†’ 6)-ß-D-glucan produced by Botryosphaeria rhodina MAMB-05, has presented antimutagenic, antiproliferative, pro-apoptotic, hypoglycemic and hypocholesterolemic effects. This study evaluated the effects of botryosphaeran (30 mg/kg b.w./day) on tumor development and cachexia syndrome in Walker-256 tumor-bearing rats, and also the metabolic and hematological profiles of these animals. MATERIALS AND METHODS: Male Wistar rats were divided into 3 groups: control (C), control tumor (CT) and control tumor botryosphaeran (CTB). On the first day, 1 × 107 Walker-256 tumor cells were inoculated subcutaneously into the right flank of the CT and CTB rats, and concomitantly treatment with botryosphaeran (30 mg/kg b.w./day) started. After the 15th day of treatment, biological parameters, tumor development, cachexia, glucose and lipid profiles, hemogram and protein expression were analyzed. KEY FINDINGS: Botryosphaeran significantly reduced tumor development (p = 0.0024) and cancer cachexia, modulated the levels of glucose, triglycerides and HDL-cholesterol, and corrected macrocytic anemia. Botryosphaeran also increased significantly the bax expression in the tumor tissue (p = 0.038) demonstrating that this (1 â†’ 3)(1 â†’ 6)-ß-D-glucan is increasing the apoptosis of tumor cells. p53, p27, bcl-2, caspase-3 and Forkhead transcription factor 3a (FOXO3a) protein expression were similar among the groups. SIGNIFICANCE: This study demonstrated that botryosphaeran was effective in decreasing tumor development and cachexia by direct and indirect mechanisms increasing apoptosis and improving the metabolic and hematological profiles.


Assuntos
Apoptose/efeitos dos fármacos , Caquexia/tratamento farmacológico , Carcinoma 256 de Walker/tratamento farmacológico , Glucanos/administração & dosagem , Animais , Caquexia/etiologia , Carcinoma 256 de Walker/patologia , Glucanos/farmacologia , Glucose/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Food Chem ; 315: 126306, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035315

RESUMO

In this work we propose the use of statistical mixture design in the construction of a biosensor device based on graphite oxide, platinum nanoparticles and biomaterials obtained from Botryosphaeria rhodina MAMB-05. The biosensor was characterized by electrochemical impedance spectroscopy. Under optimized experimental parameters by factorial design, the biosensor was applied to the voltammetric determination of chlorogenic acid (CGA) measured as 5-O-caffeoylquinic acid (5-CQA). The biosensor response was linear (R2 = 0.998) for 5-CQA in the concentration range 0.56-7.3 µmol L-1, with limit of detection and quantification of 0.18 and 0.59 µmol L-1, respectively. The new biosensing device was applied to quality control analysis based upon the determination of CGA content in specialty and traditional coffee beverages. The results indicated that specialty coffee had a significantly higher content of CGA. Principal component analysis of the voltammetric fingerprint of brewed coffees revealed that the laccase-based biosensor can be used for their discrimination.


Assuntos
Bebidas/análise , Ácido Clorogênico/análogos & derivados , Café/química , Ácido Quínico/análogos & derivados , Técnicas Biossensoriais/métodos , Ácido Clorogênico/análise , Nanopartículas Metálicas/química , Platina/química , Ácido Quínico/análise
20.
Talanta ; 210: 120642, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31987177

RESUMO

The polysaccharide carboxymethyl-botryosphaeran (CMB) was used to improve the dispersion of multi-walled carbon nanotubes (MWCNTs) in water. This feature was applied in modifying a glassy carbon electrode (GCE) to construct a sensitive voltammetric sensor for the determination of desloratadine (DESL), a tricyclic antihistamine. The morphology and spectroscopic behavior of the sensor were evaluated. The modified sensor was characterized as homogeneous, and presented a higher electroactive area and a lower charge transfer resistance compared to the unmodified GCE. Using linear sweep voltammetry at 25 mV s-1, the developed sensor presented a sensitivity of 1.018 µA L µmol-1 in the linear working range of 1.99-32.9 µmol L-1, with a detection limit of 0.88 µmol L-1 of DESL in 0.10 mol L-1 potassium hydrogen-phosphate solution (pH 8.0). In addition, the sensor showed excellent repeatability with a relative standard deviation of only 1.02% for a sequence of 10 measurements. The sensor was successfully applied in the analysis of pharmaceutical preparations containing DESL, with equivalent results compared to a validated spectrophotometric method at the 95% confidence level. The sensor was also employed in the analysis of a spiked sample of DESL in rat serum.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Glucanos/química , Loratadina/análogos & derivados , Nanotubos de Carbono/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Eletrodos , Loratadina/análise , Tamanho da Partícula , Propriedades de Superfície , Água/química
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