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1.
J Agric Food Chem ; 72(28): 15416-15426, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38955361

RESUMO

In recent years, there has been a growing interest in the pure casein fraction of milk protein, particularly ß-casein due to its physicochemical properties as well as its bio- and techno-functional properties. The utilization of self-assembled ß-caseins from bovine origin as nanocarriers for the delivery of nutraceutical compounds or drugs has increased dramatically. Concerning ß-caseins from other milk sources, the use of hypoallergenic donkey ß-caseins as a potential delivery vehicle for nutraceutical hydrophobic compounds is beginning to generate interest. The present review deals with casein micelles models, bovine and donkey ß-casein molecular structures, as well as their physical-chemical properties that account for their exploitation in nutraceutics and pharmaceutics. This review work suggests the possibility of developing delivery systems for hydrophobic bioactive compounds using ß-casein purified from hypoallergenic donkey milk, highlighting the potential of this protein as an innovative and promising vehicle for enhancing the enrichment and bioavailability of various bioactive substances in food products.


Assuntos
Caseínas , Equidae , Micelas , Leite , Animais , Caseínas/química , Bovinos , Leite/química , Portadores de Fármacos/química , Suplementos Nutricionais/análise , Interações Hidrofóbicas e Hidrofílicas
2.
Food Chem ; 428: 136757, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37413839

RESUMO

The quality parameters of cappuccinos prepared with pasteurized milk or ultra-high-temperature milk steam-injected at different temperatures by a professional coffee machine have been assessed. In particular, the protein profile, the content of vitamins and lactose, the lipid peroxidation process, and the involvement of milk proteins in the foam formation were evaluated. The nutritional quality of milk seems not affected by the steam injection treatment carried out at a temperature of 60-65 °C, but at higher temperatures a decrement of lactoperoxidase, vitamin B6 and folic acid was observed. The milk used in cappuccino preparation is very important: pasteurized milk can form a more consistent and lasting foam with respect to ultra-high-temperature milk because of the presence of ß-lactoglobulin and lactoferrin, both playing an important role in the foam formation and stability. This work would provide additional information to the coffee industry for the preparation of high nutritional and organoleptic quality cappuccinos.


Assuntos
Café , Vapor , Animais , Leite , Proteínas do Leite , Vitaminas
3.
Vet Sci ; 10(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36977272

RESUMO

Acute diarrhea is a very frequent condition affecting dogs; nevertheless, little is known about what happens in the GI tract during such conditions. Proteomics allows the study of proteins present in a specific biologic substrate, and fecal proteomic investigations have been recently implemented to study GI diseases in dogs. In the present study, the fecal protein profiles of eight dogs suffering from acute uncomplicated diarrhea at the time of inclusion was investigated for the first time, and then the same patients were followed, replicating two further evaluations at two subsequent time points (after 2 and 14 days from the first presentation), with the aim of gaining possible new insights regarding the pathologic changes in the gastrointestinal environment during such conditions. Two-dimensional gel electrophoresis (2-DE) was performed, followed by mass spectrometry. Nine spots, corresponding to four (groups of) proteins (i.e., albumin, alkaline phosphatase, chymotrypsin-C-like, and some immunoglobulins), showed significant differences at two or more of the three time points investigated, almost all behaving similarly and decreasing at T1 (2 days after the onset of the condition) and significantly increasing at T2 (14 days after the onset), mainly evidencing a reaction of the organism. Further studies including a greater number of patients and possibly different techniques are needed to confirm the present findings.

4.
Food Res Int ; 159: 111627, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35940766

RESUMO

The roles of mesophilic lactobacilli in cheese manufacturing and ripening have been widely studied, but their impacts, especially as additives in preserving liquids, on the high-moisture mozzarella cheese quality parameters remained underexplored. The current study studied and compared the effects of four preserving liquid formulations - brine solution (sodium chloride, as control), a salt mixture solution, and two lactobacilli solutions (Lactiplantibacillus plantarum IMC 509 in brine solution) or SYNBIO® (a 1:1 ratio of Lacticaseibacillus rhamnosus IMC 501 and Lacticaseibacillus paracasei IMC 502) - on the microbial, chemical (volatile fatty acids), physicochemical (moisture, weight, pH, colour), texture (adhesiveness, hardness, cohesiveness, gumminess, springiness, chewiness) and sensorial qualities of mozzarella stored for 30 days at 4 °C. The quality of the governing solution, including microbial content, lactobacilli viability, pH, turbidity, and smell, was also monitored. For the first 10 days of storage, all samples demonstrated similar physicochemical variations: the firmness and chewiness of the mozzarella lessened, the pH values of the liquid decreased, but cheese microbial growth increased, as did the levels of free fatty acids, the mozzarella pH values and skin whiteness. At day 20, mozzarella stored in mesophilic lactobacilli liquid, especially SYNBIO®, had a spongy structure, tasted more bitter and sour, and had lower pH values than mozzarella in the simple brine solution. Moreover, the cheese sample and liquid of SYNBIO® also presented higher coliform and Pseudomonas spp. counts than that detected in the control, the SYNBIO® liquid, especially in the later period of storage, exhibited a yogurt smell and increased turbidity. By contrast, Mozzarella packed into salt mixture liquid exhibited somewhat more adhesiveness and gumminess, a saltier taste and slightly higher microbial counts than the control sample. The mozzarella samples differed slightly in colour and texture as well. The overall quality changes suggested that the use of the studied mesophilic lactobacilli as governing liquid additives may not be appropriate for high-moisture mozzarella cheese preservation.


Assuntos
Queijo , Olfato , Cloreto de Sódio , Paladar
5.
Biomolecules ; 12(1)2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35053228

RESUMO

Breast cancers (BCs) may present dramatic diagnoses, both for ineffective therapies and for the limited outcomes in terms of lifespan. For these types of tumors, the search for new drugs is a primary necessity. It is widely recognized that gold compounds are highly active and extremely potent as anticancer agents against many cancer cell lines. The presence of the metal plays an essential role in the activation of the cytotoxicity of these coordination compounds, whose activity, if restricted to the ligands alone, would be non-existent. On the other hand, gold exhibits a complex biochemistry, substantially variable depending on the chemical environments around the central metal. In this review, the scientific findings of the last 6-7 years on two classes of gold(I) compounds, containing phosphane or carbene ligands, are reviewed. In addition to this class of Au(I) compounds, the recent developments in the application of Auranofin in regards to BCs are reported. Auranofin is a triethylphosphine-thiosugar compound that, being a drug approved by the FDA-therefore extensively studied-is an interesting lead gold compound and a good comparison to understand the activities of structurally related Au(I) compounds.


Assuntos
Antineoplásicos , Auranofina , Neoplasias da Mama , Ouro , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Auranofina/química , Auranofina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Ouro/química , Ouro/uso terapêutico , Humanos , Relação Estrutura-Atividade
6.
Biophys J ; 120(20): 4575-4589, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34474016

RESUMO

Amyloids are proteinaceous deposits considered an underlying pathological hallmark of several degenerative diseases. The mechanism of amyloid formation and its inhibition still represent challenging issues, especially when protein structure cannot be investigated by classical biophysical techniques as for the intrinsically disordered proteins (IDPs). In this view, the need to find an alternative way for providing molecular and structural information regarding IDPs prompted us to set a novel, to our knowledge, approach focused on UV Resonance Raman (UVRR) spectroscopy. To test its applicability, we study the fibrillation of hen-egg white lysozyme (HEWL) and insulin as well as their interaction with resveratrol, employing also intrinsic fluorescence spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The increasing of the ß-sheet structure content at the end of protein fibrillation probed by FTIR occurs simultaneously with a major solvent exposure of tryptophan (Trp) and tyrosine (Tyr) residues of HEWL and insulin, respectively, as revealed by UVRR and intrinsic fluorescence spectroscopy. However, because the latter technique is successfully used when proteins naturally contain Trp residues, it shows poor performances in the case of insulin, and the information regarding its tertiary structure is exclusively provided by UVRR spectroscopy. The presence of an increased concentration of resveratrol induces mild changes in the secondary structure of both protein fibrils while remodeling HEWL fibril length and promoting the formation of amorphous aggregates in the case of insulin. Although the intrinsic fluorescence spectra of proteins are hidden by resveratrol signal, UVRR Trp and Tyr bands are resonantly enhanced, showing a good sensitivity to the presence of resveratrol and marking a modification in the noncovalent interactions in which they are involved. Our findings demonstrate that UVRR is successfully employed in the study of aggregation-prone proteins and of their interaction with ligands, especially in the case of Trp-lacking proteins.


Assuntos
Galinhas , Proteínas Intrinsicamente Desordenadas , Amiloide , Animais , Feminino , Ligantes , Estrutura Secundária de Proteína
7.
Langmuir ; 37(33): 10166-10176, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34369787

RESUMO

Monoolein-based cubic and hexagonal mesophases were investigated as matrices for insulin loading, at low pH, as a function of temperature and in the presence of increasing amounts of oleic acid, as a structural stabilizer for the hexagonal phase. Synchrotron small angle X-ray diffraction, rheological measurements, and attenuated total reflection-Fourier transform infrared spectroscopy were used to study the effects of insulin loading on the lipid mesophases and of the effect of protein confinement in the 2D- and 3D-lipid matrix water channels on its stability and unfolding behavior. We found that insulin encapsulation has only little effects both on the mesophase structures and on the viscoelastic properties of lipid systems, whereas protein confinement affects the response of the secondary structure of insulin to thermal changes in a different manner according to the specific mesophase: in the cubic structure, the unfolding toward an unordered structure is favored, while the prevalence of parallel ß-sheets, and nuclei for fibril formation, is observed in hexagonal structures.


Assuntos
Insulina , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
8.
Nutrients ; 13(5)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947032

RESUMO

BACKGROUND: Whole milk is a good source of all the nutrients, and it also contains a sufficient number of vitamins to permit regular the growth of the neonate. Dairy cow milk can create allergy in infants less than 12 months old because of the high caseins and ß-lactoglobulin content. In these circumstances, donkey milk can represent a good replacement for dairy cows' milk in children affected by Cow Milk Protein Allergy (CMPA) because of its close chemical composition with human milk, mainly due to its low protein and low mineral content. Milk vitamin content is highly variable among mammalian species and it is strictly correlated with the vitamin status and the diet administered to the mother. Fat-soluble vitamins content in donkey milk is, on average, lower compared to ruminants' milk, while vitamin C content determined in donkey milk is higher compared to dairy cows' milk, showing a great similarity with human milk. In donkey milk, the content of vitamins of the B-complex such as thiamine, riboflavin, niacin, pyridoxine, and folic acid is higher compared to human milk. The use of donkey milk as a new functional food must be further evaluated in interdisciplinary clinical trials in which pediatricians, dietitians, and food scientists must be involved to deepen the knowledge about the positive health impact of donkey milk in different sensitive people, especially children and the elderly.


Assuntos
Equidae/fisiologia , Leite Humano/química , Leite/química , Vitaminas/química , Animais , Feminino , Humanos , Valor Nutritivo , Vitaminas/metabolismo
9.
Vet Rec Open ; 8(1): e9, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33981443

RESUMO

BACKGROUND: In the scientific literature, there are only a few manuscripts available on small animal faecal proteomics. METHODS: In the present pilot study, this evaluation was performed using pooled faecal samples from 10 clinically healthy dogs and, for the first time, in 10 clinically healthy cats by mean of two-dimensional electrophoresis followed by liquid chromatography-tandem mass spectrometry. RESULTS: Our results showed the presence of nine (albumin, alkaline phosphatase, chymotrypsin-C-like, cytosol aminopeptidase, elastase-3B/proteinase E, immunoglobulins and nuclear pore membrane glycoprotein 210) and 14 (albumin, caspase recruitment domain-containing protein, chymotrypsin-like, deleted in malignant brain tumours 1 protein-like, hypothetical protein LOC107375, immunoglobulin, kallikrein-1, superoxide dismutase, transthyretin precursor, interstitial collagenase-like) different proteins in canine and feline faeces, respectively. CONCLUSION: These preliminary findings document the presence of a range of proteins in the faeces of apparently healthy dogs and cats and may serve as a basis for larger, prospective studies to establish reference proteomic data against which diseased populations can be compared.

10.
Biomacromolecules ; 22(3): 1147-1158, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33600168

RESUMO

A method is designed to quickly form protein hydrogels, based on the self-assembly of highly concentrated lysozyme solutions in acidic conditions. Their properties can be easily modulated by selecting the curing temperature. Molecular insights on the gelation pathway, derived by in situ FTIR spectroscopy, are related to calorimetric and rheological results, providing a consistent picture on structure-property correlations. In these self-crowded samples, the thermal unfolding induces the rapid formation of amyloid aggregates, leading to temperature-dependent quasi-stationary levels of antiparallel cross ß-sheet links, attributed to kinetically trapped oligomers. Upon subsequent cooling, thermoreversible hydrogels develop by the formation of interoligomer contacts. Through heating/cooling cycles, the starting solutions can be largely recovered back, due to oligomer-to-monomer dissociation and refolding. Overall, transparent protein hydrogels can be easily formed in self-crowding conditions and their properties explained, considering the formation of interconnected amyloid oligomers. This type of biomaterial might be relevant in different fields, along with analogous systems of a fibrillar nature more commonly considered.


Assuntos
Hidrogéis , Muramidase , Amiloide , Proteínas Amiloidogênicas , Temperatura
11.
Biomedicines ; 8(10)2020 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-33081006

RESUMO

Platelet-rich plasma (PRP) is a nontransfusional hemocomponent, considered as a powerful concentrate of growth factors (GFs) therapeutically used to stimulate tissue regeneration. The use of autologous PRP, as the patient's own biological material, for therapeutic purposes represents a safe and effective alternative to conventional treatments in both human and veterinary medicine. The aim of this study was the characterization of canine PRP from rheological and biological points of view. Thus, a characterization of the viscoelastic properties of the PRP systems was performed in order to clarify the influence of different calcium concentrations, in the presence of autologous thrombin-rich solution, on the PRP gels' mechanical properties, from which the applicability of these systems in biomedical treatments is strongly dependent. Then, an evaluation of the content of GFs in PRP, activated or not with thrombin, and stored at different temperatures (37 °C and -20 °C) was performed over time, outlining, for the first time, the importance of the effect of physiological temperature (37 °C) on the production of GFs. A clinical case study conducted in a dog with a complete rupture of the common calcaneal tendon (Achilles tendon) confirmed the relevance of this hemocomponent in the daily veterinary clinical activity and the potential translational value for human health.

12.
Animals (Basel) ; 10(9)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927781

RESUMO

The aim of this study was to compare the carcass characteristics and the chemical and physical parameters of the meat produced by 10 male crossbred donkeys and 10 male mules slaughtered at 16 ± 1 years of age. The carcass weight and dressing percentage were significantly (p < 0.05) higher in mules. Samples of the muscle Longissimus thoracis (LT) were analyzed. Donkey meat showed a higher fat content, while the glycogen content was higher in the mule LT. The total collagen content was higher in the mule LT; in this muscle, the shear force values were higher compared to the donkey LT. The lightness parameter (L*) was lower in the mule LT, while the redness index (a*) was higher in the mule LT; this muscle showed a higher content of iron, while zinc was higher in the donkey muscle LT. The donkey LT muscle showed a higher content of essential amino acids (52.2%) compared to the mule LT (50.1%). The results obtained demonstrated that the chemical and physical traits of mule and donkey meat were similar to those of other kinds of equid meat.

13.
Pharmacol Res ; 161: 105123, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32822867

RESUMO

Breast cancer (BC) is the most common cancer in women and, among different BC subtypes, triple negative (TN) and human epidermal growth factor receptor 2 (HER2)-positive BCs have the worst prognosis. In this study, we investigated the anticancer activity of the root ethanolic and hexane extracts from Lithospermum erythrorhizon, a traditional Chinese herbal medicine known also as tzu ts'ao or tzu-ken, against in vitro and in vivo models of TNBC and HER2-positive BC. Treatment with L. erythrorhizon root extracts resulted in a dose-dependent inhibition of BC cell viability and in a significant reduction of the growth of TNBC cells transplanted in syngeneic mice. Acetylshikonin, a naphthoquinone, was identified as the main bioactive component in extracts and was responsible for the observed antitumor activity, being able to decrease BC cell viability and to interfere with autochthonous mammary carcinogenesis in Δ16HER2 transgenic mice. Acetylshikonin anticancer effect depends on its ability to act as a potent inhibitor of dihydrofolate reductase (DHFR), to down-regulate key mediators governing cancer growth and progression, such as HER2, Src and STAT3, and to induce apoptosis by caspase-3 activation. The accumulation of acetylshikonin in blood samples as well as in brain, kidney, liver and tumor tissues was also investigated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) highlighting that L. erythrorhizon treatment is effective in delivering the active compound into the target tissues. These results provide evidence that L. erythrorhizon extract and in particular its main component acetylshikonin are effective against aggressive BC subtypes and reveal new acetylshikonin mechanisms of action.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/prevenção & controle , Antagonistas do Ácido Fólico/farmacologia , Lithospermum , Receptor ErbB-2/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo , Animais , Antraquinonas/isolamento & purificação , Antraquinonas/farmacocinética , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Antagonistas do Ácido Fólico/isolamento & purificação , Antagonistas do Ácido Fólico/farmacocinética , Humanos , Lithospermum/química , Camundongos Transgênicos , Raízes de Plantas , Receptor ErbB-2/genética , Transdução de Sinais , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Mass Spectrom ; 55(11): e4635, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32767505

RESUMO

Kefir is a type of fermented milk obtained thanks to the introduction of "kefir grains" in mammalian milk. Kefir grains consist of lactic and acetic acid bacteria and yeasts in alternative proportions that are held together by a matrix of complex sugars known as "kefiran." Thanks to the fermentative process, the kefir milk is rich in nutraceutical substances such as amino acids, vitamins, and mineral salts. The most valuable compounds of kefir fermentation are mainly lactic acid, exopolysaccharides, and bioactive peptides, the resulting products of proteolytic release from milk proteins (caseins and whey proteins). Among the nutraceutical properties of kefir are antimicrobial and antitumor activity, immunomodulating effect, and cholesterol-lowering effect. Therefore, in light of these intriguing properties of kefir milk, in this work, a proteomic analysis, by two-dimensional electrophoresis followed by mass spectrometry, has been performed. As a result, milk-derived polypeptides were identified in commercial kefir milk from organic farming. In particular, polypeptides deriving from κ-, αs1 -, and αs2 -caseins that may have potentially beneficial effects on human health have been detected.


Assuntos
Kefir/análise , Proteínas do Leite/análise , Animais , Caseínas/análise , Eletroforese em Gel Bidimensional , Espectrometria de Massas , Agricultura Orgânica , Peptídeos/análise , Proteômica
15.
Nutrients ; 12(6)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532150

RESUMO

BACKGROUND: Vitamin D and calcium are important dietary compounds that affect bone mass, even if other minerals (potassium, zinc, etc.) and vitamins (A, C and K) are also involved. Vitamin D and certain minerals, in fact, play an important role in calcium homeostasis and calcium absorption. Hip fracture incidence is higher in Europe and the United States, where calcium is frequently included in the human diet; while the occurrence of these fractures is lower in developing countries, where diets are often poor in calcium. This condition is named the "calcium paradox", and may be partially explained by phosphate toxicity, which can negatively affect mineral metabolism. It is important to maintain correct dietary calcium-phosphate balance in order to have a healthy life, reducing the risk of osteoporotic fractures in older people. Vitamin D can also act as a hormone; vitamin D2 (ergocalciferol) is derived from the UV-B radiation of ergosterol, the natural vitamin D precursor detected in plants, fungi, and invertebrates. Vitamin D3 (cholecalciferol) is synthesized by sunlight exposure from 7-dehydrocholesterol, a precursor of cholesterol that can also act as provitamin D3. Dietary intake of vitamin D3 is essential when the skin is exposed for short periods to ultraviolet B light (UV-B), a category of invisible light rays such as UV-A and UV-C. This can be considered the usual situation in northern latitudes during the winter season, or the typical lifestyle for older people and/or for people with very white delicate skin. The actual recommended daily intake of dietary vitamin D is strictly correlated with age, ranging from 5 µg for infants, children, teenagers, and adults-including pregnant and lactating women-to 15 µg for people over 65 years.


Assuntos
Laticínios , Ingestão de Alimentos/fisiologia , Fenômenos Fisiológicos da Nutrição/fisiologia , Osteoporose/prevenção & controle , Vitamina D/administração & dosagem , Vitamina D/farmacologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Cálcio/metabolismo , Criança , Pré-Escolar , Feminino , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle , Homeostase/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fosfatos/efeitos adversos , Fosfatos/metabolismo , Gravidez , Recomendações Nutricionais , Risco , Vitamina D/metabolismo , Vitamina D/fisiologia , Adulto Jovem
16.
Front Chem ; 8: 602845, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33490036

RESUMO

A class of phosphane gold(I) compounds, made of azoles and phosphane ligands, was evaluated for a screening on the regards of Breast Cancer cell panels (BC). The compounds possess N-Au-P or Cl-Au-P bonds around the central metal, and they differ for the presence of aprotic or protic polar groups in the azoles and/or the phosphane moieties to tune their hydrophilicity. Among the six candidates, only the compounds having the P-Au-N environment and not displaying neither the hydroxyl nor carboxyl groups in the ligands were found active. The compounds were screened by MTT tests in SKBR3, A17, and MDA-MB231 cancer cells, and two compounds (namely the 4,5-dicyano-imidazolate-1yl-gold(I)-(triphenylphosphane, 5, and 4,5-dichloro-imidazolate-1yl-gold(I)-triphenylphosphane, 6) were found very cytotoxic, with the most active with an IC50 value of 3.46 µM in MDA-MB231 cells. By performing enzymatic assays in the treated cells lysates, the residual enzymatic activity of dihydrofolate reductase (DHFR) has been measured after cell treatment for 4 or 12 h in comparison with control cells. Upon 12 h of treatment, the activity of DHFR was significantly reduced in both SKBR3 and A17 cells by compounds 5 and 6, but not in human MDA-MB231 cells; interestingly, it was found remarkably high after 4 h of treatment, revealing a time dependence for the DHFR enzymatic assays. The DHFR inhibition data have been compared to those for the thioredoxin reductase (TrxR), the most recognized molecular target for gold compounds. For this latter, similar residual activities (i.e., 37 and 49% for the match of SKBR3 cells and compound 5 or 6, respectively) were found. Binding studies on the regards of ct-DNA (calf-thymus-DNA) and of plasma transporters proteins, such as BSA (bovine serum albumin) and ATF (apo transferrin), were performed. As expected for gold compounds, the data support strong binding to proteins (Ksv values range: 1.51 ÷ 2.46 × 104 M-1) and a weaker interaction with ct-DNA's minor groove (Ksv values range: 1.55 ÷ 6.12 × 103 M-1).

17.
Int J Mol Sci ; 20(7)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30979096

RESUMO

A class of gold(I) phosphane complexes have been identified as inhibitors of dihydrofolate reductase (DHFR) from E. coli, an enzyme that catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF), using NADPH as a coenzyme. In this work, to comprehend the nature of the interaction at the basis of these inhibitory effects, the binding properties of bis- and tris-phosphane gold(I) chloride compounds in regards to DHFR have been studied by emission spectroscopy and spectrophotometric assays. The lack of cysteine and seleno-cysteine residues in the enzyme active site, the most favorable sites of attack of Au(I) moieties, makes this work noteworthy. The interaction with the gold compounds results into the quenching of the DHFR tryptophan's emissions and in an enhancement of their intrinsic emission intensities. Moreover, a modulating action of NADPH is highlighted by means of an increase of the gold compound affinity toward the enzyme; in fact, the dissociation constants calculated for the interactions between DHFR and each gold compound in the presence of saturating NADPH were lower than the ones observed for the apo-enzyme. The fluorimetric data afforded to Kd values ranged from 2.22 ± 0.25 µM for (PPh3)2AuCl in the presence of NADPH to 21.4 ± 3.85 µM for 4L3AuTf in the absence of NADPH. By elucidating the energetic aspects of the binding events, we have attempted to dissect the role played by the gold phosphane/protein interactions in the inhibitory activity, resulting in an exothermic enthalpy change and a positive entropic contribution (ΔH° = -5.04 ± 0.08 kcal/mol and ΔS° = 7.34 ± 0.005 cal/mol·K).


Assuntos
Escherichia coli/enzimologia , Antagonistas do Ácido Fólico/farmacologia , NAD/metabolismo , Compostos Organoáuricos/farmacologia , Fosfinas/farmacologia , Tetra-Hidrofolato Desidrogenase/metabolismo , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Antagonistas do Ácido Fólico/química , Ouro/química , Ouro/farmacologia , Humanos , Compostos Organoáuricos/química , Fosfinas/química
18.
ScientificWorldJournal ; 2019: 2742401, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30718980

RESUMO

Different laboratory markers are routinely used in the diagnosis and management of gastrointestinal (GI) disease in dogs. In the present study, starting from feces from both healthy dogs and dogs suffering from food responsive diarrhea (FRD), we tried to find proteins differently expressed in the two groups of dogs, by using a proteomic approach. Interestingly, we found that the immunoglobulin J-chain isoform 1 (species: Canis lupus familiaris) was identified only in diseased dogs (not in healthy). J-chain combines especially IgA monomers to IgA dimers and plays a crucial role for their secretions into mucosal interface. Being the first study of that kind in the dog, it is only possible to hypothesize that their presence could be likely due to an increased activation of the immune system or to a mucosal damage or both in FRD patients. Similarly, it is still impossible to assess whether this protein could be used as diagnostic/prognostic marker of GI disease; however, this study represents a promising first step toward fecal proteomics in canine GI disorders.


Assuntos
Ração Animal/microbiologia , Diarreia/veterinária , Doenças do Cão/metabolismo , Doenças do Cão/microbiologia , Fezes/química , Doenças Transmitidas por Alimentos/veterinária , Proteoma , Animais , Cromatografia Líquida , Doenças do Cão/epidemiologia , Cães , Proteômica/métodos , Espectrometria de Massas em Tandem
19.
Colloids Surf B Biointerfaces ; 173: 210-216, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30296645

RESUMO

Caseins are a family of proteins constituted by α-caseins (αs-1 and αs-2 caseins), ß-caseins and κ-caseins. ß-caseins, in particular, show a temperature and concentration-dependent self-assembling behaviour. Recently, ß-casein micelles have been proposed as natural nanocarriers for the delivery of hydrophobic compounds, promoting their bioavailability. Until now, all studies regarding both chemical-physical characterization and applications of ß-caseins have employed the protein of bovine origin. However, it could be interesting to exploit the use of ß-caseins from other milk sources for their potential encapsulation ability and immunogenicity but, at present, no information on the self-assembling behaviour is available for ß-caseins from the milk of species different from bovine. In this work, for the first time, ß-caseins from human milk and from donkey, goat, and sheep milk were purified and their self-assembling behaviour was compared to that of a commercial bovine ß-casein, the only one for which the concentration and temperature aggregation behaviour is known. Furthermore, a preliminary evaluation of the immunogenicity potential of ß-casein from other milk sources has been performed by cross-reaction experiments using anti-ß-casein antibodies from bovine origin. The results indicated a similar self-assembling profile among all ß-caseins examined compared to the bovine ß-casein, suggesting the possible use of ß-casein from other milk sources as nanocarriers. Since donkey and human ß-casein do not cross-react with bovine anti-ß-casein antibodies, they could be particularly interesting for the development of self-assembling systems with lower hypoallergenic potential.


Assuntos
Anticorpos/metabolismo , Caseínas/metabolismo , Leite/química , Animais , Anticorpos/isolamento & purificação , Especificidade de Anticorpos , Caseínas/química , Caseínas/classificação , Caseínas/isolamento & purificação , Bovinos , Reações Cruzadas , Equidae , Feminino , Corantes Fluorescentes/química , Cabras , Humanos , Micelas , Pirenos/química , Ovinos , Especificidade da Espécie , Espectrometria de Fluorescência , Temperatura
20.
Eur J Med Chem ; 155: 418-427, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29906688

RESUMO

Basal like breast cancer (BLBC) is a very aggressive subtype of breast cancer giving few chances of survival, against which cisplatin based therapy is a compromise among the anticancer activity, the resistance development and the severe side effects. With the aim of finding new anticancer agents alternative to cisplatin, seven gold(I) azolate/phosphane compounds were evaluated in vitro by MTT tests in human MDA-MB-231, human mammary epithelial HMLE cells overexpressing FoxQ1, and murine A17 cells as models of BLBC. Two compounds, (4,5-dichloro-1H-imidazolate-1-yl)-(triphenylphosphane)-gold(I) 1 and (4,5-dicyano-1H-imidazolate-1-yl)-(triphenylphosphane)-gold(I) 2 were found very active and chosen for an in vivo study in A17 tumors transplanted in syngeneic mice. The compounds resulted to be more active than cisplatin, less nephrotoxic and generally more tolerated by the mice. This study also provides evidence that both gold(I) complexes inhibited the 19 S proteasome-associated deubiquitinase USP14 and induced apoptosis, while compound 1's mechanism of action depends also on its ability to down-regulate key molecules governing cancer growth and progression, such as STAT3 and Cox-2.


Assuntos
Antineoplásicos/farmacologia , Azóis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Compostos Organoáuricos/farmacologia , Fosfinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Azóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Compostos Organoáuricos/síntese química , Compostos Organoáuricos/química , Fosfinas/química , Relação Estrutura-Atividade
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