Prevention and treatment of diabetic retinopathy by natural antioxidant containing in chitosan-based nanomedicines

Oxidative processes are critical factors in ocular conditions that may lead to pathologies such as Diabetic Retinopahty due to structural and functional modification of the tissues, apoptosis of capillary cells and retinal microvascular changes, making the loss of vision inevitable. Application of antioxidants may reduce apoptosis and restores partially functional tissues. Considering the multiple benefits of antioxidants in DR and that conjunctival drug permeability improvement is one of the major challenges in ocular drug delivery, the major topic of this work is to study the absorption capacity and consequent bioavailability of natural antioxidants incorporated in chitosan-based nanoparticles to prevent and treat DR. In this regards, it is proposed to characterize, quantify and compare the antioxidant potential of Salvia sp. and Satureja montana extracts and their main pure antioxidants: rutin, caffeic and clorogenic acid. Then, antioxidant compounds are encapsulated into different chitosan-based nanoparticles, nanoparticles and release profile characterized and ocular permeation evaluated using in vitro cell models. Finally, the effect of antioxidant nanomedicines across human ocular is evaluated in diabetic animal after topical administration in vivo.info:eu-repo/semantics/publishedVersio

Impact of fructose and fructooligosaccharides supplementation upon the fermentation of hydrolyzed okara and its impact upon bioactive components

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Encapsulation of natural compounds in the prevention and treatment of Diabetic Retinopathy

Introduction Diabetic retinopathy is a disease resulting from diabetic chronic hyperglycemia characterized by microvascular complications in the retina, where neuronal elements responsible for vision are located. Oxidative stress has been widely regarded as the main etiological factor for the emergence of ocular disease. Antioxidant therapy has been related with inhibition of diabetes-induced abnormalities of retinal metabolism. However ocular treatment effectiveness is purely low, considering the several routes of administration. The improvement of ocular bioavailability is the ultimate era of Science. This review data encompasses new nanosystems with therapeutic potential improvements and involving routes of administration local and with a better performance facing biological barriers. Nanoparticles are described to offer real benefits to the stability, drug delivery and therapy of the patient and the most advanced treatment modalities for ocular conditions.info:eu-repo/semantics/publishedVersio

The pro- and anti-inflammatory activity of fatty acids

Inflammation is crucial to maintain homeostasis in the body. The contribution of fatty acids to the inflammatory process is exerted through a variety of mechanisms leading to cell surface modifications, activation of intracellular receptors that control inflammatory signaling processes, and changes in gene expression patterns. While long-chain saturated fatty acids induce NFkB pathway activation through TLR-4 binding, unsaturated fatty acids, such as monounsaturated, polyunsaturated, and conjugated fatty acids’ antiinflammatory ability is mediated through PPARs or GPR120. Moreover, these unsaturated fatty acids, especially omega-3 fatty acids, have immunomodulatory and cytoprotective potential, which is highly relevant for diseases with a neuroinflammatory component, such as obesity, Alzheimer’s disease, multiple sclerosis, and schizophrenia.info:eu-repo/semantics/acceptedVersio

Enzymatic hydrolysis of soymilk byproduct (Okara) by proteases extracted from Cynara Cardunculus

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Production of soy protein concentrate with the recovery of bioactive compounds: from destruction to valorization

This work aimed to develop a novel methodology based on aqueous micellar systems (AMS), for producing soy protein concentrates (SPC) from soybean flour and recovering high-valuable bioactive compounds as by-products. Ethoxylated aliphatic alcohols Tergitol 15-S-7 and Tergitol 15-S-9, non-toxic and biodegradable surfactants, were selected to form the AMS. The methodology consisted of an extractive stage of soybean flour with AMS, which rendered both a pellet, i.e., the SPC, and a supernatant containing the extracted bioactive compounds. The latter was further heated above the cloud point temperature, thus resulting in a biphasic system formed by a micelle-rich phase (MP) and an aqueous phase (AP). Obtained SPC showed a noticeable loss (∼90%) of trypsin inhibitor activity, a total protein content close to 60%, soluble protein amounts varying from 19% to 34%, and remarkable released (by simulated digestion) antioxidant and antihypertensive activities. Those indicators are similar to or even better than those corresponding to SPC from the classical acid-extraction method. The AMS also exhibited an enhanced efficiency for extracting antinutrients such as non-digestible oligosaccharides, trypsin inhibitors, and lectins mostly recovered at the AP and separated from isoflavones, which were concentrated and isolated at the MP. The recovery of all the mentioned bioactive compounds, whether beneficial or undesirable, broadens their uses in research, food, and pharmacological fields. This successful performance, simplicity, scalability, and sustainability make the proposed AMS-based extraction a powerful tool for processing plant derivatives and valorizing their by-products.info:eu-repo/semantics/publishedVersio

Encapsulation of rosmarinic acid into chitosan nanoparticles

Introduction: The use of nanotechnology in medical sciences is a innovation that promises a new age of health. Among the different approaches explored so far, chitosan exhibits favourable and unique biological properties, such as biocompatibility, biodegradability, non-antigenic, non-toxicity and mucoadhesiveness . On the other hand, natural extracts have been incorporated in chitosan films, or macro/microparticles, becoming more effective as antimicrobial or improving the antioxidant protection. The combination of antioxidants and nanoparticles is seen as the key to success in the topical administration of therapeutic antioxidants . Phenolic compound like rosmarinic acid are potent natural antioxidant with a multitude of biological activities like anti-inflammatory, antimutagen, antibacterial and antiviral as well as high potential radical scavenging activity.info:eu-repo/semantics/publishedVersio

Deuterated Ammonia in Galactic Protostellar Cores

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant (\gsim 5\sigma) \nh2d emission. Ion-molecule chemistry, which preferentially enhances deuterium in molecules above its cosmological value of \scnot{1.6}{-5} sufficiently explains these abundances. NH2D/NH3 ratios towards Class 0 sources yields information about the ``fossil remnants'' from the era prior to the onset of core collapse and star formation. We compare our observations with predictions of gas-phase chemical networks.Comment: 16 Pages, 7 Figures, Accepted to Ap.J., to appear in the June 20, 2001 editio

Development and characterization of natural antioxidant-containing chitosan nanoparticles

The use of nanotechnology in medical sciences is an innovation that promises a new age of health. Among the different approaches explored so far, chitosan exhibits favourable and unique biological properties, such as biocompatibility, biodegradability, nonantigenic, non-toxicity and mucoadhesiveness. Natural extracts rich in antioxidant molecules have been incorporated in chitosan films, or macro/microparticles, becoming more effective as improving the antioxidant protection [da Silva 2010]. In the present study, chitosan nanoparticles with extracts of sage and savoury and rosmarinic acid were prepared and characterized in order to ensure their best size, efficient encapsulation and to test the retention of the active compounds and evaluate their controlled release performance. This work proposes for the first time in literature, a simultaneous HPLC method for the determination and quantification of phenolic and flavonoid compounds, namely quercetin and rosmarinic acid encapsulated into chitosan nanoparticles. The method can be used to determine the loading capacity and association efficiency as well as its in vitro release.info:eu-repo/semantics/publishedVersio

Impact of thermal treatment and hydrolysis by Alcalase and Cynara cardunculus enzymes on the functional and nutritional value of Okara

Enzymatic hydrolysis of dried okara (autoclaved and non-autoclaved) with Alcalase (AL) and Cynara cardunculus extract (CY) was studied, assessing the impact of heat treatment and hydrolysis on potential antioxidant and antihypertensive activities of final hydrolysates. This study showed that the thermal treatment (sterilization at 121 °C, 1 atm and 15 min) facilitated the enzymatic access to substrate and increased the degree of hydrolysis (DH), especially for AL (37.9%) when compared to CY (3.6%). The antioxidant activity of dried Okara (either autoclaved or not) when hydrolysed with AL was higher (4.2 mg Trolox/mL) than that observed for CY. Additionally, the potential ACE-inhibitory activity was high for samples hydrolysed with both enzymes, however the highest ACE inhibition was also found for AL (IC50 = 9.97 µg/mL). This study allowed the identification of new peptide sequences in dried okara hydrolysed with both enzymes, and some sequences that can explain their bioactivities. The results indicate that dried okara hydrolysates can either be used as functional ingredient or as food supplement for blood pressure lowering or antioxidant applications in the future.info:eu-repo/semantics/acceptedVersio