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Medicinas Complementares
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1.
Drug Deliv ; 29(1): 1608-1619, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35612320

RESUMO

Photodynamic therapy (PDT) and photothermal therapy (PTT) have attracted research interest for their noninvasive nature and selective treatment of tumor tissues. They are effective through the generation of reactive oxygen species (ROS) or heat. Nevertheless, several problems, including low bioavailability and long-lasting cutaneous photosensitivity, have limited their clinical application. In this study, we reported an in situ self-assembly strategy that could improve various biological properties of the photosensitizer in vivo. A photosensitizer connected to a receptor-mediated smart peptide can self-assemble into nanoparticles (NPs) under the force of hydrophobic interaction and then transform into a nanofibrillar network after attaching to the tumor cell surface with the help of the ß-sheet-forming peptide KLVFF. The supramolecular structural changes deeply affected the PDT and PTT properties of the photosensitizer on tumors. After being aggregated into the nanostructure, the water solubility and targeting ability of the photosensitizer was ameliorated. Moreover, the improvement of the photothermal conversion efficiency, ROS generation, and tumor retention followed the formation of nanofibrils (NFs). This self-assembly strategy showed the ability of supramolecular nanofibrils to improve the bioavailability of photosensitizers, which provides a new potential treatment avenue for various cancer therapies.


Assuntos
Neoplasias Colorretais , Nanopartículas , Fotoquimioterapia , Clorofila/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Humanos , Peptídeos/farmacologia , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo
2.
J Sci Food Agric ; 102(14): 6771-6779, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35638177

RESUMO

BACKGROUND: The wild bitter gourd (WBG) is a commonly consumed vegetable in Asia that has antioxidant and hypoglycemic properties. The present study aimed to investigate the anti-adipogenic activities of isolated compounds from WBG on 8-day differentiated cultures of 3 T3-L1 adipocytes that were then stained with Oil Red O (ORO) or diamidino-2-phenylindole (DAPI). RESULTS: ORO stains of the methanol extracts of de-seeded HM86 cultivar of WBG (WBG-M) and the ethyl acetate fractions (WBG-M-EA) showed anti-adipogenic activities against differentiated adipocytes. Two chlorophyll-degraded compounds, pheophorbide a (1) and pyropheophorbide a (2), were isolated from WBG-M-EA. Treatments with 1 (5, 10, and 20 µmol L-1 ) and 2 (2.5, 5, and 10 µmol L-1 ) showed dose-dependent reductions in lipid accumulations and reduced nuclear DAPI stains in differentiated 3 T3-L1 adipocytes. The concentrations for 50% inhibition against lipid accumulations of 1 and 2, respectively, were 16.05 and 7.04 µmol L-1 . Treatments with 1 and 2 showed enhanced lactate dehydrogenase release in the first 4-day cell mitotic clonal expansions during the differentiating cultural processes, although the effect was less on the non-differentiating cultural processes. Thus, 1 and 2 were more toxic to differentiating adipocytes than to non-differentiated pre-adipocytes, which partly resulted in anti-adipogenic activities with lowered lipid accumulations. CONCLUSION: Both 1 and 2 showed anti-adipogenic activities in cell models. These chlorophyll-degraded compounds commonly exist in several vegetables during storage or edible seaweeds, which will provide resources for further investigations aiming to test anti-obesity in animal studies. © 2022 Society of Chemical Industry.


Assuntos
Momordica charantia , Animais , Antioxidantes , Clorofila/análogos & derivados , Hipoglicemiantes/farmacologia , Lactato Desidrogenases , Lipídeos , Metanol , Momordica charantia/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia
3.
Biomed Pharmacother ; 147: 112664, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35131655

RESUMO

The lymphatic vascular system is crucial for maintaining tissue fluid homeostasis and immune surveillance. Promoting lymphatic function represents a new strategy to treat several diseases including lymphedema, chronic inflammation and impaired wound healing. By screening a plant extract library, a petroleum ether extract from the aerial parts of Eupatorium perfoliatum (E. perfoliatum) was found to possess lymphangiogenic properties. With the aid of HPLC activity profiling the active compound was identified as pheophorbide a. Both plant extract and pheophorbide a induced the sprouting and tube formation of human primary lymphatic endothelial cells (LECs). The proliferation of the LECs was increased upon treatment with pheophorbide a but not the E. perfoliatum extract. Treatment with the MEK1/2 inhibitor U0126 reduced the LEC sprouting activity, indicating a potential mechanism of action. These studies suggest that pheophorbide a could represent novel natural therapeutic agent to treat human lymphatic vascular insufficiencies.


Assuntos
Clorofila/análogos & derivados , Células Endoteliais/efeitos dos fármacos , Eupatorium , Linfangiogênese/efeitos dos fármacos , Extratos Vegetais/farmacologia , Butadienos/farmacologia , Linhagem Celular , Clorofila/farmacologia , Humanos , Vasos Linfáticos/efeitos dos fármacos , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Nitrilas/farmacologia
4.
J Nat Med ; 75(3): 675-681, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33625682

RESUMO

Accumulation of advanced glycation end products (AGEs) plays an important role in diabetes, immunoinflammation, and cardiovascular and neurodegenerative diseases. Since AGEs mediate their pathological effects through interaction with receptor for AGEs (RAGE), RAGE antagonists would provide a useful therapeutic option for various health disorders. Therefore, in this study, we aimed to identify phytochemicals that would inhibit binding of AGEs to RAGE, which may help develop new drug leads and/or nutraceuticals for AGE-RAGE-related diseases. On screening ethanol extracts obtained from 700 plant materials collected in Myanmar, we found that the ethanol extract from the leaves of Mallotus philippensis inhibited the binding of AGEs to RAGE. We also found that the leaves of M. japonicus, which belongs to the same genera and distributes abundantly in Japan, exhibited the inhibitory activity similar to M. philippensis. Activity-guided fractionation and LC/MS analysis of the ethanol extract of M. japonicus helped identify pheophorbide a (PPBa) as a major component in the active fraction, along with some other pheophorbide derivatives. PPBa exhibited potent inhibitory activity against AGE-RAGE binding, with an IC50 value (0.102 µM) comparable to that of dalteparin (0.084 µM). PPBa may be a valuable natural product for use as a therapeutic agent and/or a nutraceutical against various health complications arising from activation of the AGE-RAGE axis.


Assuntos
Clorofila/análogos & derivados , Mallotus (Planta)/química , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Clorofila/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Mianmar , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química
5.
J Agric Food Chem ; 68(22): 6040-6047, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32374593

RESUMO

The steroid hormones, including brassinosteroids, regulate plant growth under stress. It is hypothesized that 24-epibrassinosteroids (24-EBR) can affect safflower (Carthamus tinctorius) biochemical properties, crop yield, and oil content under drought stress. The objective of our study was to determine the response of three safflower genotypes (Goldasht, Faraman, and Sina) to exogenous 24-EBR (0 and 10-7 M) under drought stress, including 85, 65, and 45% of field capacity in 2015. Stress decreased chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, relative water content (RWC), seed yield, and oil percentage. The activities of superoxide dismutase (SOD), catalase (CAT), polyphenol oxidase (PPO), and proline contents increased in response to either drought stress or 24-EBR. Genotypes behaved significantly different under stress. 24-EBR significantly increased plant chlorophyll contents and oil percentage, and it significantly reduced the malondialdehyde (MDA) content via increasing the proline and carotenoid contents under stress. 24-EBR can increase safflower oil and seed yield under drought stress.


Assuntos
Carthamus tinctorius/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Óleos de Plantas/metabolismo , Esteroides/farmacologia , Carotenoides/análise , Carotenoides/metabolismo , Carthamus tinctorius/química , Carthamus tinctorius/genética , Carthamus tinctorius/metabolismo , Clorofila/análogos & derivados , Clorofila/análise , Clorofila/metabolismo , Secas , Genótipo , Malondialdeído/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Óleos de Plantas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/química , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
6.
Photosynth Res ; 146(1-3): 189-195, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32114648

RESUMO

CO2 concentration and temperature for growth of photosynthetic organisms are two important factors to ensure better photosynthetic performance. In this study, we investigated the effects of CO2 concentration and temperature on the photosynthetic performance in a marine centric diatom Chaetoceros gracilis. Cells were grown under four different conditions, namely, at 25 °C with air bubbling, at 25 °C with a supplementation of 3% CO2, at 30 °C with air bubbling, and at 30 °C with the CO2 supplementation. It was found that the growth rate of cells at 30 °C with the CO2 supplementation is faster than those at other three conditions. The pigment compositions of cells grown under the different conditions are altered, and fluorescence spectra measured at 77 K also showed different peak positions. A novel fucoxanthin chlorophyll a/c-binding protein complex is observed in the cells grown at 30 °C with the CO2 supplementation but not in the other three types of cells. Since oxygen-evolving activities of the four types of cells are almost unchanged, it is suggested that the CO2 supplementation and growth temperature are involved in the regulation of photosynthetic light-harvesting apparatus in C. gracilis at different degrees. Based on these observations, we discuss the favorable growth conditions for C. gracilis.


Assuntos
Dióxido de Carbono/farmacologia , Diatomáceas/fisiologia , Fotossíntese/fisiologia , Clorofila/análogos & derivados , Clorofila/metabolismo , Clorofila A/metabolismo , Diatomáceas/metabolismo , Fluorescência , Temperatura , Xantofilas/metabolismo
7.
Theranostics ; 10(1): 62-73, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31903106

RESUMO

Rationale: Nanoparticles (NPs) that are rapidly eliminated from the body offer great potential in clinical test. Renal excretion of small particles is preferable over other clearance pathways to minimize potential toxicity. Thus, there is a significant demand to prepare ultra-small theranostic agents with renal clearance behaviors. Method: In this work, we report a facile method to prepare NPs with ultra-small size that show renal clearable behavior for imaging-guided photodynamic therapy (PDT). Pyropheophorbide-a (Pa), a deep red photosensitizer was functionalized with polyethylene glycol (PEG) to obtain Pa-PEG. The prepared NPs formed ultra-small nanodots in aqueous solution and showed red-shifted absorbance that enabling efficient singlet oxygen generation upon light irradiation. Results: In vitro studies revealed good photodynamic therapy (PDT) effect of these Pa-PEG nanodots. Most of the cancer cells incubated with Pa-PEG nanodots were destroyed after being exposed to the irradiated light. Utilizing the optical properties of such Pa-PEG nanodots, in vivo photoacoustic (PA) and fluorescence (FL) imaging techniques were used to assess the optimal time for PDT treatment after intravenous (i.v.) injection of the nanodots. As monitored by the PA/FL dual-modal imaging, the nanodots could accumulate at the tumor site and reach the maximum concentration at 8 h post injection. Finally, the tumors on mice treated with Pa-PEG nanodots were effectively inhibited by PDT treatment. Moreover, Pa-PEG nanodots showed high PA/FL signals in kidneys implying these ultra-small nanodots could be excreted out of the body via renal clearance. Conclusion: We demonstrated the excellent properties of Pa-PEG nanodots that can be an in vivo imaging-guided PDT agent with renal clearable behavior for potential future clinical translation.


Assuntos
Neoplasias da Mama/terapia , Sobrevivência Celular/efeitos dos fármacos , Clorofila/análogos & derivados , Nanopartículas , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia/métodos , Animais , Linhagem Celular Tumoral , Clorofila/uso terapêutico , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Técnicas Fotoacústicas , Nanomedicina Teranóstica
8.
Braz. j. med. biol. res ; 53(1): e8389, Jan. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055479

RESUMO

Photodynamic therapy (PDT) promotes cell death, and it has been successfully employed as a treatment resource for neuropathic complications of diabetes mellitus (T1DM) and hepatocellular carcinoma. The liver is the major organ involved in the regulation of energy homeostasis, and in pathological conditions such as T1DM, changes in liver metabolic pathways result in hyperglycemia, which is associated with multiple organic dysfunctions. In this context, it has been suggested that chlorophyll-a and its derivatives have anti-diabetic actions, such as reducing hyperglycemia, hyperinsulinemia, and hypertriglyceridemia, but these effects have not yet been proven. Thus, the biological action of PDT with chlorophyll-a on hepatic parameters related to energy metabolism and oxidative stress in T1DM Wistar rats was investigated. Evaluation of the acute effects of this pigment was performed by incubation of isolated hepatocytes with chlorophyll-a and the chronic effects were evaluated by oral treatment with chlorophyll-based extract, with post-analysis of the intact liver by in situ perfusion. In both experimental protocols, chlorophyll-a decreased hepatic glucose release and glycogenolysis rate and stimulated the glycolytic pathway in DM/PDT. In addition, there was a reduction in hepatic oxidative stress, noticeable by decreased lipoperoxidation, reactive oxygen species, and carbonylated proteins in livers of chlorophyll-treated T1DM rats. These are indicators of the potential capacity of chlorophyll-a in improving the status of the diabetic liver.


Assuntos
Animais , Masculino , Ratos , Clorofila/análogos & derivados , Fármacos Fotossensibilizantes/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Glicólise/efeitos dos fármacos , Fígado/fisiopatologia , Fotoquimioterapia , Clorofila/administração & dosagem , Ratos Wistar , Estresse Oxidativo/fisiologia , Diabetes Mellitus Experimental/patologia , Quimioterapia Combinada , Metabolismo Energético/efeitos dos fármacos , Glicólise/fisiologia , Fígado/patologia
9.
Environ Monit Assess ; 191(11): 679, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655913

RESUMO

Algal treatment methods have been widely used in nutrient removal studies. However, in most cases, the experimental conditions have not been fully complied with actual conditions. For instance, the effect of algae acclimation to wastewater medium on cell growth and removal efficiency has generally been ignored in laboratory scale experiments. This paper investigates the effect of acclimation on cell growth and nutrient uptake rates of Arthrospira platensis and Chlorella vulgaris. For this purpose, batch reactors, which contained the synthetic secondary effluent, had been inoculated by acclimated algae cells and the growth parameters were measured daily, as well as nutrient concentration. A significant decrease (P < 0.05) in chlorophyll-a content of acclimated A. platensis was observed, although there was no significant change in specific growth rate (µ) and doubling time (dt), in comparison with the non-acclimated ones. Moreover, the acclimation process changed the chlorophyll-a content and kinetic parameters of Chlorella vulgaris. Furthermore, t test results showed a significant increase in removal rate of nitrogen compounds through the acclimation. Residence time of A. platensis and C. vulgaris was also reduced through the acclimation by approximately 50% and 25%, respectively.


Assuntos
Chlorella vulgaris/fisiologia , Eliminação de Resíduos Líquidos/métodos , Aclimatação , Chlorella vulgaris/crescimento & desenvolvimento , Clorofila/análogos & derivados , Monitoramento Ambiental , Cinética , Nitrogênio/análise , Nutrientes , Fósforo/análise , Spirulina/fisiologia , Águas Residuárias
10.
Environ Sci Pollut Res Int ; 26(30): 31414-31421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31478174

RESUMO

Phosphorus (P) characteristics in eutrophic lakes change during algal growth. Furthermore, algae have a significant relationship with the microbial communities of lake sediments. This study addressed the influence of algal growth and soluble reactive phosphorus (SRP) concentrations on P characteristics within the sediment-water-algal (SWA) system. Results indicated that the SWA system simulating a high algal bloom level (SWA-HAB) had a correspondingly high SRP concentration (258.9 µg L-1), and that algal growth promoted a high SRP concentration in the overlying water. The high SRP concentration in overlying water could support algal growth, resulting in a high chlorophyll a (Chl-a) concentration (285.23 mg L-1). During algal growth, the P release flux was high in sediments from the high-SRP SWA system, with the highest P release flux measured at 0.982 mg m-2 day-1. Furthermore, microbial community abundance had a significant relationship with Chl-a concentrations in overlying water (p < 0.05) and increases with algae growth.


Assuntos
Eutrofização , Sedimentos Geológicos/microbiologia , Microbiota , Fósforo/análise , Poluentes Químicos da Água/análise , China , Clorofila/análogos & derivados , Clorofila A , Lagos , Água
11.
Angew Chem Int Ed Engl ; 58(42): 14974-14978, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31410962

RESUMO

A nanoemulsion with a porphyrin shell (NewPS) was created by the self-assembly of porphyrin salt around an oil core. The NewPS system has excellent colloidal stability, is amenable to different porphyrin salts and oils, and is capable of co-loading with chemotherapeutics. The porphyrin salt shell enables porphyrin-dependent optical tunability. The NewPS consisting of pyropheophorbide a mono-salt has a porphyrin shell of ordered J-aggregates, which produced a narrow, red-shifted Q-band with increased absorbance. Upon nanostructure dissociation, the fluorescence and photodynamic reactivity of the porphyrin monomers are restored. The spectrally distinct photoacoustic imaging (at 715 nm by intact NewPS) and fluorescence increase (at 671 nm by disrupted NewPS) allow the monitoring of NewPS accumulation and disruption in mice bearing KB tumors to guide effective photodynamic therapy. Substituting the oil core with Lipiodol affords additional CT contrast, whereas loading paclitaxel into NewPS facilitates drug delivery.


Assuntos
Portadores de Fármacos/química , Óleo Etiodado/química , Nanopartículas/química , Neoplasias , Paclitaxel/administração & dosagem , Técnicas Fotoacústicas/métodos , Porfirinas/química , Nanomedicina Teranóstica/métodos , Animais , Clorofila/análogos & derivados , Clorofila/química , Emulsões , Humanos , Células KB , Camundongos Nus , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Paclitaxel/uso terapêutico , Tamanho da Partícula , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Environ Monit Assess ; 191(6): 318, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044287

RESUMO

The representativeness of aquatic ecosystem monitoring and the precision of the assessment results are of high importance when implementing the EU's Water Framework Directive that aims to secure a good status of waterbodies in Europe. However, adapting monitoring designs to answer the objectives and allocating the sampling resources effectively are seldom practiced. Here, we present a practical solution how the sampling effort could be re-allocated without decreasing the precision and confidence of status class assignment. For demonstrating this, we used a large data set of 272 intensively monitored Finnish lake, coastal, and river waterbodies utilizing an existing framework for quantifying the uncertainties in the status class estimation. We estimated the temporal and spatial variance components, as well as the effect of sampling allocation to the precision and confidence of chlorophyll-a and total phosphorus. Our results suggest that almost 70% of the lake and coastal waterbodies, and 27% of the river waterbodies, were classified without sufficient confidence in these variables. On the other hand, many of the waterbodies produced unnecessary precise metric means. Thus, reallocation of sampling effort is needed. Our results show that, even though the studied variables are among the most monitored status metrics, the unexplained variation is still high. Combining multiple data sets and using fixed covariates would improve the modeling performance. Our study highlights that ongoing monitoring programs should be evaluated more systematically, and the information from the statistical uncertainty analysis should be brought concretely to the decision-making process.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Clorofila/análogos & derivados , Clorofila/análise , Ecossistema , Monitoramento Ambiental/estatística & dados numéricos , Europa (Continente) , Finlândia , Lagos , Fósforo/análise , Rios , Qualidade da Água
13.
J Control Release ; 305: 120-129, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31096018

RESUMO

Combination chemotherapy now becomes the most standard cancer treatment protocol. Here, we present a core-shell type polymeric microgel (CSPM) which combines photodynamic and chemo therapeutic modalities in one-pot system. CSPM localizes in the malignant lesion after intratumoral injection, releases reactive oxygen species (ROS) and anticancer drug (5'-deoxy-5-fluorocytidine; DFCR) under the near-infrared (NIR) laser treatment. Pheophorbide A (PheoA)-linked poly(hydroxyethyl methacrylate) (poly-HEMA) was designated to a ROS-generating core, and chemically covered with a chitosan shell. In addition, phenylboronic acid was employed in chitosan shells and linked to DFCR to form an ROS cleavable boronic ester. The core-shell structure of CSPM was determined by transmission electron microscopy. NIR-responsive photodynamic ROS generation was confirmed by the oxidative reduction of 9,10-dimethylanthracene (a fluorescent dye), and the cascadic release of DFCR by ROS was confirmed by a release study and a live and dead cell imaging study. Typically, poly-HEMA cored microgel increased its volume by 48.9-fold after absorption of body fluid. This swelling property ensured CSPM was retained in tumor tissues after subtumoral injection and the suitability of CSPM for locoregional phototherapy. The therapeutic effect of CSPM was attributed to the combined, cascadic deliveries of cytotoxic ROS and DFCR and confirmed by growth inhibition studies in in vitro pancreatic cancer cells and in vivo colon cancer mouse model.


Assuntos
Antineoplásicos/uso terapêutico , Clorofila/análogos & derivados , Desoxicitidina/análogos & derivados , Microgéis/uso terapêutico , Neoplasias/terapia , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Clorofila/química , Clorofila/uso terapêutico , Terapia Combinada , Preparações de Ação Retardada/química , Preparações de Ação Retardada/uso terapêutico , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Humanos , Raios Infravermelhos , Terapia a Laser , Camundongos Endogâmicos BALB C , Microgéis/química , Neoplasias/metabolismo , Neoplasias/patologia , Poli-Hidroxietil Metacrilato/química , Poli-Hidroxietil Metacrilato/uso terapêutico , Água/química
14.
Biosci Biotechnol Biochem ; 83(7): 1181-1192, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31032736

RESUMO

Interaction between foods and drugs is an important consideration in pharmaceutical therapy. Therefore, here, we examined the suppressive effects of the extracts from seven edible herbs on the induction of CYP3A4 gene expression in rifampicin-treated HepG2 cells. We evaluated the structure and suppressive activity of the most effective active compound isolated from dried peppermint (Mentha piperita L.). The structure of the compound was identified as that of pheophorbide a based on spectroscopic data. It suppressed the induction of CYP3A4 mRNA expression by rifampicin in a dose-dependent manner. Quantitative high-performance liquid chromatography showed that 2 g of dry leaves 0.43 mg in one cup of peppermint tea. These findings demonstrate that pheophorbide a suppresses the induction of CYP3A4 mRNA expression in rifampicin-treated HepG2 cells. Pheophorbide is known to cause photosensitivity. However, the effective dose of pheophorbide a that had a suppressive effect was very low, indicating a high safety margin. Abbreviations: DAD: diode array detector; DMEM: Dulbecco's modified Eagle's medium; ELISA: enzyme-linked immunosorbent assay; HPLC: high-performance liquid chromatography; PCR: polymerase chain reaction; PXR: pregnane X receptor; CAR: constitutive androstane receptor; AHR: aryl hydrocarbon receptor; TLC: thin-layer chromatography.


Assuntos
Antibióticos Antituberculose/farmacologia , Clorofila/análogos & derivados , Citocromo P-450 CYP3A/genética , Mentha piperita/química , Extratos Vegetais/farmacologia , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , Rifampina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Clorofila/química , Clorofila/farmacologia , Cromatografia Líquida de Alta Pressão , Células Hep G2 , Humanos , Estrutura Molecular , Extratos Vegetais/química , Espectroscopia de Prótons por Ressonância Magnética , Relação Estrutura-Atividade
15.
Environ Sci Pollut Res Int ; 26(12): 11940-11950, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825122

RESUMO

Dust storms affect the primary productivity of the ocean by providing necessary micronutrients to the surface layer. One such dust storm during March 2012 led to a substantial reduction in visibility and enhancement in aerosol optical depth (AOD) up to ~ 0.8 (AOD increased from 0.1 to 0.9) over the Arabian Sea. We explored the possible effects and mechanisms through which this particular dust storm could impact the ocean's primary productivity (phytoplankton concentration), using satellite-borne remote sensors and reanalysis model data (2003-2016). The climatological analyses revealed anomalous March 2012 in terms of dust deposition and enhancement in phytoplankton concentration in the month of March during 2003-2016 over this region. The studied dust storm accounts for increase in the daily average surface dust deposition rate from ~ 3 to ~53 mg m-2 day-1, which is followed by a significant enhancement in the chlorophyll-a (Chl_a) concentration (~ 2 to ~9 mg m-3). We show strong association between a dust storm and an event of anomalously high biological production (with a 4-day forward lag) in the Arabian Sea. We suggest that the increase in biological production results from the superposition of two complementary processes (deposition of atmospheric nutrients and deepening of the mixed layer due to dust-induced sea surface temperature cooling) that enhance nutrient availability in the euphotic layer.


Assuntos
Poluentes Atmosféricos/análise , Poeira/análise , Monitoramento Ambiental , Fitoplâncton/fisiologia , Aerossóis/análise , Clorofila/análogos & derivados , Clorofila A , Fitoplâncton/crescimento & desenvolvimento , Estações do Ano
16.
Phytother Res ; 33(3): 702-707, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30648298

RESUMO

This study was designed to determine the inhibitory effects of pheophorbide A on carbohydrate digesting enzymes and its ability to improve postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Pheophorbide A caused noticeable inhibitory effects on α-glucosidase and α-amylase, with half-maximal inhibitory concentrations (IC50 ) of 80.65 ± 5.90 and 76.48 ± 6.31 µM, respectively. The pheophorbide-mediated inhibition of α-glucosidase and α-amylase was significantly more effective than that of the positive control, acarbose. The increase in postprandial blood glucose levels was more significantly suppressed in the pheophorbide A group than in the control group of STZ-induced diabetic mice. In addition, the area under the curve was decreased by pheophorbide A intake in STZ-induced diabetic mice. Our results suggested that pheophorbide A may help to improve postprandial hyperglycemia by inhibiting the activity of carbohydrate digesting enzymes.


Assuntos
Clorofila/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/farmacologia , Hiperglicemia/prevenção & controle , Rodófitas/química , Animais , Glicemia/efeitos dos fármacos , Clorofila/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estreptozocina
17.
Braz. j. biol ; 78(3): 579-587, Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951578

RESUMO

Abstract Current study investigated the effectiveness of different macrophytes as culture media for Ankistrodesmus gracilis in laboratory conditions. Significant difference (p < 0.05) was reported in cell density with regard to conventional culture medium (CHU12) and macrophytes culture media. Mean cell density in NPK, Eichhornia crassipes and E. azurea media was higher (p < 0.05) than in conventional culture medium. Chlorophyll-a was higher than 1 g.L-1, except in CHU12 (0.7 ± 0.4 g.L-1) and T. domingensis (0.8 ± 0.3 g.L-1) media. Nitrate decreased sharply as from the 7th-day of the experiment. Ammonium and total phosphorus were highest in culture media and ranged between 0.4 g.L-1 (P. cordata medium) and 1.7 g.L-1 (CHU12 medium) for ammonium, and between 0.8 g.L-1 (CHU12 medium) and 1.9 g.L-1 (T. domingensis medium) for total phosphorus. Results revealed inorganic fertilizer and macrophytes combined with vitamins may be effective as culture media and strongly supports the growth of Ankistrodesmus gracilis, since cell density and biochemical composition are similar to or higher than conventional culture medium (CHU12). Macrophyte is a tool for aquaculture since biological wastes may be used with nutrients to improve the cultivation of microalgae.


Resumo O presente estudo investigou a eficácia na utilização de diferentes macrófitas como meio de cultura para Ankistrodesmus gracilis em condições laboratoriais. Foi observada diferença significativa (p < 0,05) entre a densidade celular em relação aos meios de cultura convencional (CHU12) e de macrófitas. Os meios de cultura com Eichhornia crassipes, E. azurea e NPK apresentaram densidade celular maiores (p < 0,05) que o meio de cultura convencional. Os teores de clorofila-a foram superiores a 1 g.L-1, exceto nos meios de cultura CHU12 (0.7 ± 0.4 g.L-1) e de T. domingensis (0.7 ± 0.3 g.L-1). O nitrato diminuiu acentuadamente a partir do 7º dia de experimento. Dentre os nutrientes, amônia e o fósforo total foram os mais elevados nos meios de cultura, variando entre 0.4 g.L-1 (meio de P. cordata) a 1,7 g.L-1 (meio CHU12) para amônia e, entre 0.8 g.L-1 (meio CHU12) e 1,9 gL-1 (meio de T. domingensis) para o fósforo total. Os resultados do presente estudo mostraram que o uso de fertilizantes inorgânicos e macrófitas, combinados com vitaminas, pode ser eficaz como meio de cultura no crescimento de Ankistrodesmus gracilis, uma vez que a densidade celular e a composição bioquímica foram semelhantes ou superiores ao meio de cultura convencional (CHU12). As macrófitas são ferramentas a serem adotadas na aquicultura, desde que os resíduos biológicos podem ser usados como nutrientes para melhorar o cultivo de microalgas.


Assuntos
Aquicultura , Meios de Cultura/química , Clorófitas/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Águas Residuárias/química , Fósforo , Brasil , Clorofila/análogos & derivados , Clorófitas/química , Microalgas/química , Fertilizantes , Águas Residuárias/análise , Clorofila A , Nitratos , Valor Nutritivo
18.
Ecotoxicol Environ Saf ; 166: 192-199, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30269014

RESUMO

Harmful cyanobacterial blooms are a growing threat to freshwater ecosystems worldwide due to the production of microcystin (MC), which can have detrimental effects on water quality and human health. The relations between MC-producing Microcystis, MC production, and environmental variables especially nutrient conditions in eutrophic lakes, Lake Taihu and Lake Yanghe, were investigated during the bloom season of 2015. Results showed that toxigenic cells contributed to 8.94-75.68% and 7.87-58.69% of the total Microcystis in Lake Taihu and Lake Yanghe, respectively. The dynamics of toxigenic cells and MC production were positively associated with NH3-N concentration in Lake Taihu, while positively associated with the concentrations of TP, TDP and PO4-P in Lake Yanghe, indicating that the dominant nutrient factor affecting the toxic blooms was nitrogen in Lake Taihu, whereas it was phosphorus in Lake Yanghe. The significant relationship between TLR eq (total MC after transformation of MC-RR and MC-YR into MC-LR) and Chlorophyll-a (Chl-a) concentration implied that Chl-a could be an alternative measure to predict MC risk in the two lakes, and the safe threshold value of Chl-a was proposed as 25.38 and 31.06 µg/L in Lake Taihu and Lake Yanghe, respectively.


Assuntos
Lagos/microbiologia , Microcistinas/análise , Microcystis/genética , China , Clorofila/análogos & derivados , Clorofila/análise , Genótipo , Lagos/química , Toxinas Marinhas , Nitrogênio/análise , Nutrientes , Fósforo/análise
19.
Lasers Surg Med ; 50(5): 506-512, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29737551

RESUMO

BACKGROUND AND OBJECTIVES: In this study, we evaluated the impact of hyperthermia in photosensitizing efficacy of 3-[(1'-hexyloxy)ethyl-3-devinylpyropheophorbide-a (HPPH or Photochlor) for the treatment of cancer by photodynamic therapy (PDT). STUDY DESIGN/MATERIALS AND METHODS: The outcome of both whole body hyperthermia (WBH) and local hyperthermia (LH) in combination with HPPH-PDT was determined in BALB/c and nude mice bearing Colon26 and U87 tumors, respectively. LH was performed by using an indigenously designed heating device, that was heated to the required temperature using a circulating water bath. The device which has flexible membrane on one side was placed on skin above the tumor. The temperature of the tumor was monitored using a thermocouple sensor placed on the surface of the tumor capable of measuring the temperature within 0.1°C. Uptake of the photosensitizer in tumors was determined by fluorescence using an IVIS or a Nuance Imaging System. The PDT was performed by exposing the tumors to 665 nm laser loght, (135 J/cm2 , 75 mW/cm2 ) at the maximal uptake time of HPPH. Tumor size was measured daily using vernier calipers. RESULTS: The improved PDT efficacy (long-term percentage tumor cure) in combination with hyperthermia is possible due to an increase in tumor-uptake of the photosensitizer (PS), confirmed by in vivo fluorescence imaging and also by increased tumor perfusion and decreased hypoxia as have been reported previously (Sen et al. [2011] Cancer Res. 71:3872-3880 In Vivo. 20:689-695). Interestingly, compared to whole body hyperthermia, the 14 C- HPPH biodistribution data under local hyperthermia showed similar tumor-uptake in BALB/c mice bearing Colon26 tumors, but significantly lower uptake in other organs and in the blood. CONCLUSION: Our study demonstrates that both, fever range whole body and local hyperthermia in combination with HPPH-PDT enhances the long-term tumor cure of BALB/c and nude mice implanted with Colon26 and U87 tumors respectively. Lasers Surg. Med. 50:506-512, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Clorofila/análogos & derivados , Neoplasias do Colo/terapia , Hipertermia Induzida/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Animais , Clorofila/farmacologia , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
20.
Braz J Biol ; 78(3): 579-587, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29166430

RESUMO

Current study investigated the effectiveness of different macrophytes as culture media for Ankistrodesmus gracilis in laboratory conditions. Significant difference (p < 0.05) was reported in cell density with regard to conventional culture medium (CHU12) and macrophytes culture media. Mean cell density in NPK, Eichhornia crassipes and E. azurea media was higher (p < 0.05) than in conventional culture medium. Chlorophyll-a was higher than 1 g.L-1, except in CHU12 (0.7 ± 0.4 g.L-1) and T. domingensis (0.8 ± 0.3 g.L-1) media. Nitrate decreased sharply as from the 7th-day of the experiment. Ammonium and total phosphorus were highest in culture media and ranged between 0.4 g.L-1 (P. cordata medium) and 1.7 g.L-1 (CHU12 medium) for ammonium, and between 0.8 g.L-1 (CHU12 medium) and 1.9 g.L-1 (T. domingensis medium) for total phosphorus. Results revealed inorganic fertilizer and macrophytes combined with vitamins may be effective as culture media and strongly supports the growth of Ankistrodesmus gracilis, since cell density and biochemical composition are similar to or higher than conventional culture medium (CHU12). Macrophyte is a tool for aquaculture since biological wastes may be used with nutrients to improve the cultivation of microalgae.


Assuntos
Aquicultura , Clorófitas/crescimento & desenvolvimento , Meios de Cultura/química , Microalgas/crescimento & desenvolvimento , Águas Residuárias/química , Brasil , Clorofila/análogos & derivados , Clorofila A , Clorófitas/química , Fertilizantes , Microalgas/química , Nitratos , Valor Nutritivo , Fósforo , Águas Residuárias/análise
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