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1.
Methods Mol Biol ; 2373: 107-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34520009

RESUMO

Protection of the central nervous system (CNS) and cerebral homeostasis depend upon the blood-brain barrier (BBB) functions and permeability. BBB restrictive permeability hinders drug delivery for the treatment of several neurodegenerative diseases and brain tumors. Several in vivo animal models and in vitro systems have been developed to understand the BBB complex mechanisms and aid in the design of improved therapeutic strategies. However, there are still many limitations that should be addressed to achieve the structural and chemical environment of a human BBB. We developed a microfluidic-based model of the neurovascular unit. A monolayer of human cerebral endothelial cells (hCMEC-D3) was grown and cocultured with human brain microvascular pericytes (hBMVPC), and human induced pluripotent stem cells differentiated into astrocytes (hiPSC-AC) and neurons (hiPSC-N). To visualize the physiological morphology of each cell type, we used fluorescent cell-specific markers and confocal microscopy. Permeation of fluorescent solutes with different molecular weights was measured to demonstrate that the developed BBB was selectively permeable as a functional barrier.

2.
Methods Mol Biol ; 2373: 283-296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34520019

RESUMO

This protocol describes a comprehensive practical guide for the biofabrication of 3D in vitro models of vascularized and mineralized bone Minitissues. These models give the possibility to study the contribution of physical and biochemical parameters on bone vascularization, as well as the osteoblast/osteoclast mediated matrix remodeling. Based on the specific pathophysiological processes to be investigated, the 3D bone Minitissues allow to select the most suitable cell composition, by coculturing up to four cell types, and to customize the material properties of the hydrogel matrix. Considering their versatility, these 3D bone Minitissues could be relevant for the recapitulation of bone pathologies such as bone tumors and metastases and could be and used as screening platforms to test antimetastatic drugs.

3.
Methods Mol Biol ; 2384: 1-27, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34550565

RESUMO

Oxytocin and oxytocin receptors are synthesized in the periphery where paracrine/autocrine actions have been described alongside endocrine actions effected by central release of oxytocin from the posterior pituitary. In the female reproductive system, classical actions of uterine contraction and milk ejection from mammary glands are accompanied by actions in the ovaries where roles in steroidogenesis, follicle recruitment and ovulation have been described. Steroidogenesis, contractile activity, and gamete health are similarly affected by oxytocin in the male reproductive tract. In the cardiovascular system, a local oxytocinergic system appears to play an important cardio-protective role. This role is likely associated with emerging evidence that peripheral oxytocin is an important hormone in the endocrinology of glucose homeostasis due to its actions in adipose, the pancreas, and the largely ignored oxytocinergic systems of the adrenal glands and liver. Gene polymorphisms are shown to be associated with a number of reported traits, not least factors associated with metabolic syndrome.

4.
Methods Mol Biol ; 2389: 87-94, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558004

RESUMO

Neural stem cells (NSCs) transplantation enhances plasticity and restores functions in neurological diseases. Therapeutic benefits of NSCs are due to their ability to replace the lost neurons and glial cells and also secreting a wide array of free and membrane-bound bioactive molecules that can reduce the hostility of diseased microenvironment, resolve inflammation, and rescue damaged neural cells. Membrane-encircled spherical nanostructures that are collectively known as extracellular vesicles (EVs) contain mRNA, miRNA, lipids, and specific proteins that affect different biological processes in cells located nearby or at far distances. Using EVs as an alternative non-cell-based therapy has gained huge attention, and developing methods for large-scale production of EVs is of great clinical importance. Here, we describe an efficient method to yield significant quantity of EVs from human NSCs that are expanded under free floating neurosphere assay culture system. Using the neurosphere assay in bioreactors under GMP-compliant conditions can result in scalable NSC-EVs required for human trials.

5.
Methods Mol Biol ; 2389: 95-102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558005

RESUMO

Adult neural precursor cells are an integral part of the brain and have been a focus of intense research for half a century. Even though adult neural stem/progenitor cells in the human brain have been identified over 20 years ago, progress in this area has been slow, and the existence of lifelong neurogenesis in humans is still debated. Remarkable species differences exist between humans and rodents in astrocyte development and diversity, suggesting similar differences may exist in neural stem/progenitor cells and underscoring the need for further research in human tissue.This chapter provides a guideline for dissociation of adult human brain tissue from biopsy or autopsy specimens. While protocols for subsequent culturing of neural precursors are included, the main focus is the preparation of a suspension of viable single cells that may also be useful in other experimental paradigms, such as genomic profiling.

6.
Methods Mol Biol ; 2389: 111-123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558007

RESUMO

The renewable source of neural stem cells (NSCs) with multi-lineage differentiation capability toward neurons, astrocytes, and oligodendrocytes represents an ideal supply for cell therapy of central nervous system (CNS) diseases. In spite of this, the clinical use of NSCs is hampered by heterogeneity, poor neuronal cell yield, predominant astrocytic differentiation of NSC progeny, and possible uncontrolled proliferation and tumor formation upon transplantation. The ability to generate highly enriched and defined neural cell populations from the renewable source of NSCs might overcome many of these impediments and pave the way toward their successful clinical applications.Here, we describe a simple method for NSC differentiation and subsequent purification of neuronal progenitor cells, taking advantage of size and granularity differences between neuronal cells and other NSC progeny. This highly enriched neuronal cell population provides an invaluable source of cells for both in vitro and in vivo studies.

7.
Methods Mol Biol ; 2389: 155-164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558009

RESUMO

Even with therapeutic hypothermia as standard of care, hypoxic-ischemic encephalopathy in neonates often causes long-term disabilities. Stem cell therapy may be a successful treatment for HIE both in the acute and chronic time periods post-injury. Neurogenic astrocytes with characteristics of neural stem cells can be cultured as adherent monolayers and be induced to generate neuronal progeny in vitro and in vivo following reintroduction into the neural stem cell niche of both neonatal and adult hosts. Thus, these neurogenic astrocytes represent promising candidates for cell replacement therapy in HIE. Such an approach requires optimized cell cultivation protocols as well as extensive testing of donor cells to assess their capacity for engraftment, survival, and integration in the HIE animal models. In this chapter, we will describe methods of generating the HIE model, generating and culturing monolayer neurogenic astrocytes, and transplanting these cells into HIE animal models.

8.
Methods Mol Biol ; 2389: 165-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558010

RESUMO

Neural stem cell therapy has been galvanized by the discovery of pluripotent stem cells. The possibility to generate specialized central nervous system-specific differentiated cells using human somatic cells engineered to become induced pluripotent stem cells (iPSCs) was a game changer. This technology has broad applications in the field of regenerative medicine, in vitro disease modeling, targeted drug discovery, and precision medicine. Currently, iPSCs are one of the most promising cell sources amenable for commercialization and off-the-shelf neural stem cell therapy products. iPSCs exhibit a strong self-renewable ability that supports the development of a virtually unlimited source of neural cells for structural repair in neurological disorders. However, along with this strong proliferative capacity of iPSCs comes the tumorigenic potential of these cells after transplantation. Thus, the isolation and purification of a homogeneous population of human neural stem cells (hNSCs) are of paramount importance to ensure consistency in the composition of the cellular product and to avoid tumor formation in the host brain. This chapter describes the isolation, neuralization, and long-term perpetuation of hNSCs derived from iPSCs through the use of specific growth medium and the preparation of hNSCs for transplantation in an experimental model of stroke. Additionally, we will describe methods to analyze the ischemic stroke and size of grafts using magnetic resonance imaging and OsiriX software and neuroanatomical tracing procedures to study axonal remodeling after ischemic stroke and cell transplantation.

9.
Food Chem ; 366: 130504, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273856

RESUMO

Drying process affected the qualitative indicators of green coffees; chlorogenic acid (CGAs), total phenolic content (TPC), antioxidant activities and CIE-lab color to varying degrees. Sun drying and heat pump drying resulted in comparable levels of CGAs and antioxidant activities in green coffees; however, color parameters, especially lightness (L*), differed. Correlation analyses indicated a relationship between specific CGAs, antioxidant activities and color parameters among coffees. PLS analysis revealed that the high contents of 5-caffeoylquinic acid in green coffees did not correlate with antioxidant activities. Results from CGAs contents and PCA analysis provided a linkage to previous research relating important components and quality indices of both green and roasted coffees as affected by postharvest drying. Results indicated that heat pump drying at 50 °C is a viable alternative and possibly superior to sun drying for preserving certain desirable chemical and physical characteristics of green coffee.


Assuntos
Ácido Clorogênico , Coffea , Antioxidantes , Ácido Clorogênico/análise , Café , Tailândia
10.
Food Chem ; 366: 130546, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273857

RESUMO

Effects of cysteine (Cys) treatments (0, 0.01%, 0.05% and 0.10%) on sensory quality and bioactive compounds in goji fruit stored at 4 °C and 90% RH for 10 d were investigated. Results indicated that 0.05% Cys treatment significantly reduced decay ratio and weight loss, and maintained total soluble solid content in goji fruit. Furthermore, 0.05% Cys treatment increased the contents of total phenolic, ascorbic acid and total glutathione, and the ratio of glutathione/oxidized glutathione, resulting in the higher antioxidant capacity. Determination of five free amino acids showed that 0.05% Cys treatment increased the Pro and Tau contents, while had no significant effect on the Cys, Glu and GABA contents. The increase in Tau content might be due to the up-regulation of two key genes involved in the Tau synthesis including CDO and CSAD. These findings suggested that Cys treatment could improve the storage quality in goji fruit.


Assuntos
Cisteína , Frutas , Antioxidantes , Ácido Ascórbico , Frutas/química , Fenóis/análise
11.
Food Chem ; 366: 130571, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284185

RESUMO

Plant cell cultures from cloudberry (CL), lingonberry (LI), stone berry (ST), arctic bramble (AB), and strawberry (SB) were studied in terms of their polyphenol and carotenoid composition, antioxidant activity, antihemolytic activity and cytotoxicity effects on cancerous cells. High-resolution mass spectrometry data showed that LI, presented the highest antioxidant activity, contained the highest contents of flavones, phenolic acids, lignans, and total carotenoids, while CL, ST and SB presented the opposite behavior. AB and SB presented the lowest FRAP and CUPRAC values, while AB and CL presented the lowest reducing power. SB presented the lowest antioxidant activity measured by single electron transfer assays and the lowest content of lignans, phenolic acids, and flavones. CL and LI decreased the viability of in vitro mammary gland adenocarcinoma while only LI decreased the viability of in vitro lung carcinoma and showed protective effects of human erythrocytes against mechanical hemolysis.


Assuntos
Frutas , Fenóis , Antioxidantes , Carotenoides , Técnicas de Cultura de Células , Frutas/química , Humanos , Fenóis/análise , Extratos Vegetais
12.
Food Chem ; 366: 130557, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284195

RESUMO

Diacylglycerol (DAG) is commonly used as fat substitute in food manufacture due to its functional properties, but DAG has poor emulsification and oxidation stability, which limits its wide application in food industry. In this work, fluorescence quenching data and thermodynamic parameters were analyzed to investigate the interaction mechanism between l-theanine (L-Th) and ß-lactoglobulin (ß-LG). DAG emulsion was prepared by using ß-lactoglobulin-theanine (ß-LG-Th) as surface stabilizer, and its emulsification and oxidation stability were evaluated. The results showed that the hydrophobic interaction played an important role on the conjugate of ß-LG and L-Th due to the negative values for ΔG, positive values for ΔH and ΔS at pH 4.0, pH 6.0 and pH 8.0. The DAG has been better embedded by using ß-LG-Th as surface stabilizer, and the droplet size was about 0.2 µm to 1.5 µm when the pH was 6.0, the ratio of L-Th to ß-LG was 1:1. ß-LG-Th as surface stabilizer for DAG can increase the ζ-potential and emulsion index, make the emulsion droplet size distribution more uniform. The l-theanine was better to be used to improve the emulsification stability and antioxidant capacity of DAG by binding ß-LG as surface stabilizer.


Assuntos
Antioxidantes , Lactoglobulinas , Diglicerídeos , Emulsões , Glutamatos , Interações Hidrofóbicas e Hidrofílicas
13.
Food Chem ; 366: 130562, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34289442

RESUMO

In this work, new approaches for the green extraction of polyphenols from sour cherry pomace were explored. Three Natural Deep Eutectic Solvents (NADES) systems based on choline chloride (ChCl) as a hydrogen bond acceptor (HBA) and malic acid, urea, and fructose (MalA, Ur, and Fru) as hydrogen bond donors (HBD) were used. NADES systems were prepared by heating and stirring (H&S), ultrasound (US), and microwave (MW) methods. It was found that MW-assisted preparation was the fastest requiring less than 30 s. Polyphenol extraction from cherry pomace was performed also by three mentioned methods, and compared with conventional methods. MW extraction was the most rapid with less than 5 min necessary for the extract preparation. All three NADES systems were highly efficient for anthocyanin extraction, but the most efficient was ChCl:MalA system. Extract based on ChCl:MalA system was for 62.33% more efficient for anthocyanin extraction comparing with the conventional solvent.


Assuntos
Polifenóis , Prunus avium , Micro-Ondas , Extratos Vegetais , Solventes
14.
Food Chem ; 366: 130494, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34293544

RESUMO

Bioactive peptides have recently gained more research attention as potential therapies for the management of bodily disorders and metabolic syndromes of delicate health importance. On another note, there is a rising trend on a global scale for the consumption and adoption of fruit and vegetables for the fulfilment of dietary and health needs. Furthermore, fruits and vegetables are being more studied as base materials for the isolation of biologically functional components and accordingly, they have been investigated for their concomitant bioactive peptides. This review focuses on isolation and bio-functional properties of bioactive peptides from fruits and vegetables. This manuscript is potential in serving as a material collection for fundamental consultancy on peptides derived from fruits and vegetables, and further canvasses the necessitation for the use of these food materials as primal matter for such.


Assuntos
Frutas , Verduras , Dieta , Peptídeos
15.
Food Chem ; 366: 130592, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34293549

RESUMO

An exhaustive migration study of eight corks, made of ethylene-vinyl acetate, was carried out to identify any non-volatile and volatile compounds using an untargeted approach. The challenge associated with the structural elucidation of unknowns was undertaken using both ultra-high-performance liquid chromatography coupled to an ion-mobility separation quadrupole-time of flight mass spectrometer and gas chromatography mass spectrometry. A total of fifty compounds were observed to migrate from the corks, and among these additives such as antioxidants (Butyl 4-hydroxybenzoate, Irganox 1010, Irganox 1075, Irgafos 168 and BHT) or lubricants (EBO and octadecanamide, N,N'-1,2-ethanediylbis-) were identified. A high proportion (84%) of the detected compounds was non-intentionally added substances (NIAS), and included several cyclic oligomers with different chain sequences. NIAS, such as 2,6-bis(1,1-dimethylethyl)-4-ethyl and 7,9-ditert-butyl-1-oxaspiro[4.5]deca-6,9-diene-2,8-dione, break-down products, including hexa-, hepta- and nonadecanamide, N,N'-1,2-ethanediylbis-, and oxidation products were also identified. One cork was found to be unsuitable for use as a food contact material.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Cromatografia Líquida , Etilenos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Compostos de Vinila
16.
Food Chem ; 366: 130604, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34298395

RESUMO

The aroma profiles of fresh flat peach juice (FPJ) samples obtained from four different cultivars (RP1), (ZLP), (RP18), and (ZP) were characterized by gas chromatography-Mass spectrometry-olfactometry (GC-MS-O). Totally, 32 aroma-active compounds in FPJs were identified by GC-MS-O and further quantified. Of these, 14 aroma-active compounds presented odor activity values (OAVs) greater than 1, with several lactones and aldehydes contributing as key aroma-active components of FPJs. Partial least-squares regression (PLSR) revealed that RP18 was greatly related to "fruity", "sweet" and "peach-like" attributes, while ZLP was highly correlated with "floral" and "green and grassy" attributes, confirming the quantitative describe analysis (QDA) results. In addition, an aroma recombination experiment was conducted to mimic the aroma profile of flat peach juice based on the actual concentrations of RP18. Omission experiments indicated that lactones were very highly significant for the characteristic aroma of FPJ.


Assuntos
Prunus persica , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria , Compostos Orgânicos Voláteis/análise
17.
Food Chem ; 366: 130530, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303204

RESUMO

In this study, the effects of different temperatures, incubation times and types of reducing sugars, including glucose and different low molecular weight (Mw) chito-oligosaccharides (COS) with varying acetylation degree (AD), on the extent of Maillard reaction (MR) on chitosan-based films were studied. Interestingly, an improvement of structural and functional properties of all MR-crosslinked films was noted, which is more pronounced by heating at higher temperature and exposure time. These findings were proved through Fourier-transform infrared and X-ray diffraction analyses. In addition, color change and Ultraviolet spectra demonstrate that glucose addition provides the high extent of MR, followed by COS1 (Mw < 4.4 kDa; AD, 18.20%) and COS2 (Mw < 4.4 kDa; AD, 10.63%). These results were confirmed by enhanced water resistance and thermal properties. Moreover, MR-chitosan/COS films showed the highest mechanical properties, whereas, glucose-loaded films were brittle, as demonstrated by scanning electron microscopy micrographs. Furthermore, MR-chitosan/COS1 films exhibited the better antioxidant behavior followed by chitosan/glucose and chitosan/COS2 films, mainly at higher heating-conditions. Thereby, MR-crosslinked chitosan/COS based films were attractive to be applied as functional and active coating-materials in various fields.


Assuntos
Quitosana , Antioxidantes , Glucose , Reação de Maillard , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Food Chem ; 366: 130574, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303209

RESUMO

There is growing interest in chitosan-based intelligent packaging films for monitoring food quality. However, practical application of these biopolymeric films has been limited by their poor physical and mechanical attributes. Herein, a versatile colorimetric indicator film was developed based on chitosan (CHI) and broken Riceberry phenolic extract (RPE). The effects of RPE fortification on the microstructure, physical, and functional attributes of the CHI films were comprehensively evaluated. The results revealed that CHI-RPE films exhibited increased hydrophobicity, mechanical resistance, thermal stability, barrier properties, and antioxidant activity compared to plain CHI film. The CHI-RPE films were cytocompatible. Notably, CHI-RPE film also produced intense naked-eye detectable colorimetric response to pH (2-12) variation and volatile ammonia. When enclosed with fresh shrimp, CHI-RPE film changed from orange-red to yellow in response to shrimp spoilage. Thus, CHI-RPE film has high potential for fabricating pragmatic, smart packaging labels for on-site visual detection of freshness in seafood products.


Assuntos
Quitosana , Antocianinas , Antioxidantes , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Extratos Vegetais , Alimentos Marinhos/análise
19.
Food Chem ; 366: 130613, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34304136

RESUMO

A colorimetric and fluorescence dual-signal method based on sulfur quantum dots (SQDs) was established for determination of iron (II) (Fe2+) and H2O2 in foods. Due to the complexation of Fe2+ with SQD, Fe2+ can cause fluorescence quenching of SQDs, and the color of the mixed solution changed from light yellow to deep green. By use of Fenton reaction, H2O2 can restore the quenched fluorescence of SQDs, and the color of the mixture changed from green to colorless. The concentration of Fe2+ and H2O2 has a good linear relationship with the fluorescence intensity and absorbance in the range of 2.5-55 µM and 1.25-500 µM, and the detection limits were 1.41 µM and 0.54 µM, respectively. For determination of H2O2, the linear ranges were 1.17-1.97 mM and 0.867-1.50 mM, and the detection limits were 0.03 µM and 0.06 µM, respectively.


Assuntos
Pontos Quânticos , Colorimetria , Peróxido de Hidrogênio , Ferro , Enxofre
20.
Food Chem ; 366: 130590, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311230

RESUMO

A paper-based electrochemiluminescence device (µPAD-ECL) for the estimation of trimethylamine (TMA) concentration in fish was developed using tris(2,2'-bipyridyl)ruthenium(II) complex coupled with water soluble thioglycolic acid-capped CdSe quantum dots on the inkjet-printed paper-based device. The quenching effect of tertiary amines on the ECL intensity was found to be sensitive and concentration dependent. This effect allows the measurement of TMA at low concentrations. Under the optimal conditions, the linear concentration range was exhibited from 1 × 10-12 to 1 × 10-7 M and a detection limit of 2.09 × 10-13 M, with relative standard deviation of 1.97 %. The applicability of µPAD-ECL is demonstrated by the rapid estimation of trimethylamine concentration in fish tissue, and could be used as a method for screening the total amount of tertiary amines in fishery products in remote communities. The results obtained using the paper-based devices agreed well with those obtained applying high performance liquid chromatography with benzoyl derivatization, at a confidence level of 95%.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Animais , Medições Luminescentes , Metilaminas , Compostos de Selênio , Tioglicolatos
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