16 research outputs found
Improving the Therapeutic Potential of G-CSF through Compact Circular PEGylation Based on Orthogonal Conjugations
: In this study, a circular conjugate of granulocyte colony-stimulating factor (G-CSF) was prepared by conjugating the two end-chains of poly(ethylene glycol) (PEG) to two different sites of the protein. For the orthogonal conjugation, a heterobifunctional PEG chain was designed and synthesized, bearing the dipeptide ZGln-Gly (ZQG) at one end-chain, for transglutaminase (TGase) enzymatic selective conjugation at Lys41 of G-CSF, and an aldehyde group at the opposite end-chain, for N-terminal selective reductive alkylation of the protein. The cPEG-Nter/K41-G-CSF circular conjugate was characterized by physicochemical methods and compared with native G-CSF and the corresponding linear monoconjugates of G-CSF, PEG-Nter-G-CSF, and PEG-K41-G-CSF. The results demonstrated that the circular conjugate had improved physicochemical and thermal stability, prolonged pharmacokinetic interaction, and retained the biological activity of G-CSF. The PEGylation strategy employed in this study has potential applications in the design of novel protein-based therapeutics
Poly(L-glutamic acid)-co-poly(ethylene glycol) block copolymers for protein conjugation
Poly(L-glutamic acid)-co-poly(ethylene glycol) block copolymers (PLE-PEG) are here investigated as polymers for conjugation to therapeutic proteins such as granulocyte colony stimulating factor (G-CSF) and human growth hormone (hGH). PLE-PEG block copolymers are able to stabilize and protect proteins from degradation and to prolong their residence time in the blood stream, features that are made possible thanks to PEG's intrinsic properties and the simultaneous presence of the biodegradable anionic PLE moiety. When PLE-PEG copolymers are selectively tethered to the N-terminus of G-CSF and hGH, they yield homogeneous monoconjugates that preserve the protein's secondary structure. During the current study the pharmacokinetics of PLE10-PEG20k-G-CSF and PLE20-PEG20k-G-CSF derivatives and their ability to induce granulopoiesis were, respectively, assessed in Sprague-Dawley rats and in C57BL6 mice. Our results show that the bioavailability and bioactivity of the derivatives are comparable to or better than those of PEG20k-Nter-G-CSF (commercially known as Pegfilgrastim). The therapeutic effects of PLE10-PEG20k-hGH and PLE20-PEG20k-hGH derivatives tested in hypophysectomized rats demonstrate that the presence of a negatively charged PLE block enhances the biological properties of the conjugates additionally with respect to PEG20k-Nter-hGH
Anti-HER2 Super Stealth Immunoliposomes for Targeted-Chemotherapy
: Liposomes play an important role in the field of drug delivery by virtue of their biocompatibility and versatility as carriers. Stealth liposomes, obtained by surface decoration with hydrophilic polyethylene glycol (PEG) molecules, represented an important turning point in liposome technology, leading to significant improvements in the pharmacokinetic profile compared to naked liposomes. Nevertheless, the generation of effective targeted liposomes - a central issue for cancer therapy - has faced several difficulties and clinical phase failures. Active targeting remains a challenge for liposomes. In this direction, we designed a new Super Stealth Immunoliposomes (SSIL2) composed of a PEG-bi-phospholipids derivative that stabilizes the polymer shielding over the liposomes. Furthermore, its counterpart, conjugated to the fragment antigen-binding of trastuzumab (Fab'TRZ -PEG-bi-phospholipids), is firmly anchored on the liposomes surface and correctly orients outward the targeting moiety. Throughout this study, the performances of SSIL2 are evaluated and compared to classic stealth liposomes and stealth immunoliposomes in vitro in a panel of cell lines and in vivo studies in zebrafish larvae and rodent models. Overall, SSIL2 shows superior in vitro and in vivo outcomes, both in terms of safety and anticancer efficacy, thus representing a step forward in targeted cancer therapy, and valuable for future development. This article is protected by copyright. All rights reserved
Caratterizzazione della frazione volatile di specie erbacee originarie delle Viote del Monte Bondone
Studio dei composti organici volatili (COV) da specie erbacee originarie delle Viote del Monte Bondone (TN) per mezzo di analisi gascromatografica (GC
Use of soybean acid oils in broiler diets: effect on chicken meat oxidability
Fats and oils are usually used in animal feeding because they represent the main source of energy and they provide several essential nutrients, such as polyunsaturated fatty acids. On the market, there are many different available fat sources for poultry diets and nowadays there is an increasing interest about searching for new alternative sources. One of these alternative sources is represented by the by-products derived from the refining of edible oils, because some of them (e.g. acid oils and fatty acid distillates) can satisfy the energy and nutritional requirements, and at the same time, their use would contribute to the sustainability of the food chain and reduce the costs.
EU recently defined acid oils and fatty acid distillates and some previous studies have assessed these by-products in order to study quality and safety aspects about their use in animal production, protecting both consumers and animals.
However, there is a lack of information about several aspects of these fat sources: strict composition characterization, nutritional quality, ability to modify lipid composition of foods from animal origin (e.g. meat, fish fillets, eggs), effect on the oxidative stability of these foods, and toxicological or physiological effects of some fat degradation compounds and of some undesirable contaminants.
It is widely known that lipid oxidation is a cause of meat degradation, especially in cooked meat products, and, consequently, responsible of the quality reduction, affecting colour, nutritional value, taste and aroma. Furthermore, it is important to consider that the lipid composition of meat directly depends on the fat source composition used in feed formulations. The main factors involved in the oxidative stability and influenced by diet are fatty acid profile and tocopherols and tocotrienol content. However, other antioxidants and prooxidants present in the diet might have an effect.
The global objective of the whole project is to characterize the acid oils and fatty acid distillates coming from industrial refining and to generate practical information about their use in feeding monogastric animals (including broilers, pigs and basses) and to study the repercussions on the lipid quality of meats and fish fillets. Specifically, the present work focuses on the study of chicken meat composition and their influence on oxidative stability. In the present work it was studied how broiler feed containing soybean acid oils as fat source may affect meat oxidability.
To evaluate the oxidative status of the chicken meat different analytical methods were used to quantify lipid oxidation products. First, the primary lipid oxidation was assessed through the major primary lipid oxidation products, lipid hydroperoxides (measured by FOX method). Then, secondary lipid oxidation was determined by the measurement of malondialdehyde (TBA values) and the content of the volatile compounds was measured by SPME/GC-MS.
Broiler diets have been divided into three groups, depending on the dietary treatment received: crude soybean oil (CS), soybean acid oil (AS) and refined soybean oil (RS), and the meat samples obtained have been divided into three different meat treatments: Fresh, Cooked and Cooked & refrigerated.
Lipid fraction and tocopherols and tocotrienols content were studied, comparing feeds and meats. For PUFA n-3 content, as well as for SFA and MUFA, the differences in dietary treatments are reflected in FA composition of meats. Also tocopherol and tocotrienol values in meats show that, except for the α-T, the content of the tocopherols and tocotrienols reflected the content of the diets. These results demonstrate that dietary treatments directly influence FA and tocopherols and tocotrienols contents of meat. The composition of the different fat sources (CS, AS and RS) used in feeds is reflected in the lipid composition of chicken meat.
The magnitude of the differences found in meat between the different dietary treatments used (CS, AS and RS) is low, in terms of FA profile and tocopherols and tocotrienols content. Consequently, this might explain why no significant differences were found in oxidation parameters of meats, considering the dietary treatment factor.
Results obtained from the analysis of oxidation parameters reveal that oxidative stability is strongly influenced by meat technological treatment (cooking, refrigeration). It is widely studied that heat and storage increment the meat susceptibility to lipid oxidation. The measurements of the main parameters used to evaluate oxidative status of chicken meat (FOX method, TBA values and volatile profile) show higher values regarding Cooked and Cooked & refrigerated meat.
The study of sample clustering by the principal component analysis (PCA), clearly shows a correspondence between the primary and secondary products of lipid oxidation and the meat technological treatments, in which the cooking process and refrigerated storage are involved, further confirm the effect of meat processing on the oxidative status of meat
Comparison of three different methodologies for the quantification of hydroxytyrosol and tyrosol in olive oils, in relation to the health claim
The association between body composition and quality of life among elderly Italians
Objective This study aimed to assess the body composition and quality of life in elderly Italian people and to value the association between these variables. Methods Height, weight, humerus breadth, circumferences, skinfolds, and hand grip strength were measured in 256 older adults (age: M: 81.1 +/- 7.3, F: 84.9 +/- 8.1 years). Body mass index, waist-hip ratio, waist-height ratio, upper-arm areas, and body composition parameters were calculated. Quality of life (QoL) was measured by WHO Quality of Life-BREF questionnaire (WHOQOL-BREF). Differences between sexes were valued. A multiple regression analysis was carried out to assess the influence of nutritional status and of socio-demographic characteristics on QoL. Results The participants were in average overweight. Even if the percentage of overweight/obese subjects was high in both sexes, males presented a more centripetal fat distribution. These characteristics, joined to data regarding lower values of arm-muscle area and hand grip strength, put males at greater risk of cardiometabolic diseases. Regarding quality of life assessments, psychological domain showed the worst scores, and, marital status resulted the main explanatory variable for this domain. Conclusions Social care facilities for the elderly people require planning strategies based on health promotion criteria in order to accentuate active ageing interventions to ameliorate the quality of life of residents
HPLC-MS/MS Phenolic Characterization of Olive Pomace Extracts Obtained Using an Innovative Mechanical Approach
Olive pomace results from the production of olive oil. Even if olive pomace represents a potential environmental problem, it contains phenolic compounds, which are widely recognized for their beneficial properties for human health. In this study, an innovative and sustainable technological approach to extract phenolic compounds from fresh olive pomace, based on food-grade solvent instead of those usually adopted, is investigated. Characterization and shelf-life evaluation of the hydroalcoholic extracts obtained from the procedure developed for different industrial purposes were also carried out. The phenolic fractions of the different samples were studied with the FolinâCiocaÌlteu method to quantify that the total reducing molecules and HPLC-MS/MS analysis was used to define the profile through the identification and quantification of 42 compounds, belonging to five chemical families. Regarding shelf-life, the hydroalcoholic extract showed no significant reduction in phenolic content, for both instrumental evaluations, retaining most of the phenolic compounds present in the raw material; negative attributes were not perceived by sensory evaluation. Thus, these lab-scale results can be the starting point to develop a procedure that is suitable for a real olive mill, representing a valorization strategy in a circular economy and the perspective of new business models
Edible insects in mixed-sourced protein meals for animal feed and food: An EU focus
Despite insects being nutritious and a sustainable protein source, entomophagy is not widely accepted by Western consumers. After EFSA's positive risk assessment report, few species can be legally farmed and processed in the EU under measures set out in Novel Foods regulation 2015/2283. This review summarizes scientific progress in the applications of insects as feed and complementary proteins in foods during the past five years including legislative frameworks covering this trajectory. Despite numerous opportunities presented, insects farming still faces challenges such as gaps in legislative policies, high initial R&D costs, and high costs involved in Life Cycle Assessment. As with other novel foods, insect production requires new value chains and attention to standardization, food safety-related issues, certification for mass production, and consumer acceptance. Therefore, the roles of public sector, scientific community, local authorities, and legislative bodies are extremely important in increasing awareness of sustainability implications and benefits of insects as food and feed