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1.
Nutrients ; 16(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38613059

RESUMO

High protein intake during infancy results in accelerated early weight gain and potentially later obesity. The aim of this follow-up study at 12 months was to evaluate if modified low-protein formulas fed during early infancy have long-term effects on growth and metabolism. In a double-blinded RCT, the ALFoNS study, 245 healthy-term infants received low-protein formulas with either alpha-lactalbumin-enriched whey (α-lac-EW; 1.75 g protein/100 kcal), casein glycomacropeptide-reduced whey (CGMP-RW; 1.76 g protein/100 kcal), or standard infant formula (SF; 2.2 g protein/100 kcal) between 2 and 6 months of age. Breastfed (BF) infants served as a reference. At 12 months, anthropometrics and dietary intake were assessed, and serum was analyzed for insulin, C-peptide, and insulin-like growth factor 1 (IGF-1). Weight gain between 6 and 12 months and BMI at 12 months were higher in the SF than in the BF infants (p = 0.019; p < 0.001, respectively), but were not significantly different between the low-protein formula groups and the BF group. S-insulin and C-peptide were higher in the SF than in the BF group (p < 0.001; p = 0.003, respectively), but more alike in the low-protein formula groups and the BF group. Serum IGF-1 at 12 months was similar in all study groups. Conclusion: Feeding modified low-protein formula during early infancy seems to reduce insulin resistance, resulting in more similar growth, serum insulin, and C-peptide concentrations to BF infants at 6-months post intervention. Feeding modified low-protein formula during early infancy results in more similar growth, serum insulin, and C-peptide concentrations to BF infants 6-months post intervention, probably due to reduced insulin resistance in the low-protein groups.


Assuntos
Fórmulas Infantis , Resistência à Insulina , Humanos , Lactente , Peptídeo C , Seguimentos , Proteínas de Ligação ao GTP , Insulina , Fator de Crescimento Insulin-Like I , Lactalbumina , Aumento de Peso , Estudos Prospectivos
2.
J Agric Food Chem ; 72(15): 8285-8303, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38588092

RESUMO

The gut barrier plays an important role in health maintenance by preventing the invasion of dietary pathogens and toxins. Disruption of the gut barrier can cause severe intestinal inflammation. As a natural source, milk is enriched with many active constituents that contribute to numerous beneficial functions, including immune regulation. These components collectively serve as a shield for the gut barrier, protecting against various threats such as biological, chemical, mechanical, and immunological threats. This comprehensive review delves into the active ingredients in milk, encompassing casein, α-lactalbumin, ß-lactoglobulin, lactoferrin, the milk fat globular membrane, lactose, transforming growth factor, and glycopeptides. The primary focus is to elucidate their impact on the integrity and function of the gut barrier. Furthermore, the implications of different processing methods of dairy products on the gut barrier protection are discussed. In conclusion, this study aimed to underscore the vital role of milk and dairy products in sustaining gut barrier health, potentially contributing to broader perspectives in nutritional sciences and public health.


Assuntos
Caseínas , Leite , Animais , Leite/metabolismo , Caseínas/metabolismo , Lactalbumina/metabolismo , Lactoglobulinas/metabolismo , Dieta
3.
Soft Matter ; 20(9): 2100-2112, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38348915

RESUMO

In this study, we conducted a comprehensive computational investigation of the interaction between α-lactalbumin, a small globular protein, and strong anionic oligoelectrolyte chains with a polymerization degree from 2 to 9. Both the protein and oligoelectrolyte chains are represented using coarse-grained models, and their properties were calculated by the Monte Carlo method under constant pH conditions. We were able to estimate the effects of this interaction on the electrostatic potential around the protein. At acidic pH, the protein had a net positive charge; therefore, the electrostatic potential around it was also positive. To neutralize or reverse this electrostatic potential, oligoelectrolyte chains with a minimum size of six monomers were necessary. Simultaneously, low salt concentrations were required as elevated salt levels led to a significant attenuation of the electrostatic interactions and the corresponding electrostatic potential.


Assuntos
Lactalbumina , Cloreto de Sódio , Lactalbumina/química , Eletricidade Estática , Concentração de Íons de Hidrogênio
4.
Compr Rev Food Sci Food Saf ; 23(1): e13288, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284584

RESUMO

Whey protein derived bioactives, including α-lactalbumin, ß-lactoglobulin, bovine serum albumin, lactoferrin, transferrin, and proteose-peptones, have exhibited wide ranges of functional, biological and therapeutic properties varying from anticancer, antihypertensive, and antimicrobial effects. In addition, their functional properties involve gelling, emulsifying, and foaming abilities. For these reasons, this review article is framed to understand the relationship existed in between those compound levels and structures with their main functional, biological, and therapeutic properties exhibited either in vitro or in vivo. The impacts of hydrolysis mechanism and separation techniques in enhancing those properties are likewise discussed. Furthermore, special emphasize is given to multifunctional effects of whey derived bioactives and their future trends in ameliorating further food, pharmaceutical, and nutraceutical products. The underlying mechanism effects of those properties are still remained unclear in terms of activity levels, efficacy, and targeted effectiveness. For these reasons, some important models linking to functional properties, thermal properties and cell circumstances are established. Moreover, the coexistence of radical trapping groups, chelating groups, sulfhydryl groups, inhibitory groups, and peptide bonds seemed to be the key elements in triggering those functions and properties. Practical Application: Whey proteins are the byproducts of cheese processing and usually the exploitation of these food waste products has increasingly getting acceptance in many countries, especially European countries. Whey proteins share comparable nutritive values to milk products, particularly on their richness on important proteins that can serve immune protection, structural, and energetic roles. The nutritive profile of whey proteins shows diverse type of bioactive molecules like α-lactalbumin, ß-lactoglobulin, lactoferrin, transferrin, immunoglobulin, and proteose peptones with wide biological importance to the living system, such as in maintaining immunological, neuronal, and signaling roles. The diversification of proteins of whey products prompted scientists to exploit the real mechanisms behind of their biological and therapeutic effects, especially in declining the risk of cancer, tumor, and further complications like diabetes type 2 and hypertension risk effects. For these reasons, profiling these types of proteins using different proteomic and peptidomic approaches helps in determining their biological and therapeutic targets along with their release into gastrointestinal tract conditions and their bioavailabilities into portal circulation, tissue, and organs. The wide applicability of those protein fractions and their derivative bioactive products showed significant impacts in the field of emulsion and double emulsion stabilization by playing roles as emulsifying, surfactant, stabilizing, and foaming agents. Their amphoteric properties helped them to act as excellent encapsulating agents, particularly as vehicle for delivering important vitamins and bioactive compounds. The presence of ferric elements increased their transportation to several metal-ions in the same time increased their scavenging effects to metal-transition and peroxidation of lipids. Their richness with almost essential and nonessential amino acids makes them as selective microbial starters, in addition their richness in sulfhydryl amino acids allowed them to act a cross-linker in conjugating further biomolecules. For instance, conjugating gold-nanoparticles and fluorescent materials in targeting diseases like cancer and tumors in vivo is considered the cutting-edges strategies for these versatile molecules due to their active diffusion across-cell membrane and the presence of specific transporters to these therapeutic molecules.


Assuntos
Neoplasias , Peptidomiméticos , Eliminação de Resíduos , Humanos , Proteínas do Soro do Leite/metabolismo , Lactalbumina/metabolismo , Proteínas do Leite/química , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia , Lactoferrina/metabolismo , Peptonas/metabolismo , Hidrólise , Emulsões , Proteômica , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Aminoácidos
5.
Nutrients ; 16(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38201979

RESUMO

Shifts toward increased proteolytic fermentation, such as, for example, in athlete and high-protein weight loss diets, may alter the relative abundance of microbial species in the gut and generate bioactive, potentially deleterious metabolic products. In the current investigation, intestinal (caecal) microbiota composition was studied in rats fed diets differing only in their constituent proteins: milk (casein (CAS), lactalbumin (LA)) or legume (Cicer arietinum, Lupinus angustifolius) protein isolates (chickpea protein isolate (CPI), lupin protein isolate (LI)). ANOSIM and Discriminant Analysis showed significant (p < 0.05) differences at both family and genus levels in both microbiota composition and functionality as a consequence of feeding the different proteins. Differences were also significant (p < 0.05) for predicted functionality parameters as determined by PICRUSt analysis. LA induced a generally healthier microbiota composition than CAS, and higher amounts of Methanobrevibacter spp. and Methanogenic_PWY were found in the LI group. LEfSe analysis of bacterial composition and functional activities revealed a number of groups/functions able to explain the different effects found with milk and legume protein isolates. In conclusion, the mostly beneficial modulation of intestinal microbiota generally found with legume-based diets is likely to be due, at least in part, to their constituent proteins.


Assuntos
Cicer , Fabaceae , Microbioma Gastrointestinal , Microbiota , Humanos , Animais , Ratos , Leite , Dieta , Verduras , Caseínas , Lactalbumina , Leguminas
6.
Expert Opin Drug Metab Toxicol ; 20(1-2): 61-72, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38226638

RESUMO

INTRODUCTION: This Expert Opinion covers recent updates in the use of Inositol in polycystic ovary syndrome (PCOS) and type II diabetes and gives support to researchers and clinicians. AREAS COVERED: This article discusses the role of Myo-Inositol (MI) and D-Chiro-Inositol (DCI) in physiological function, the use of MI in PCOS, the risks of using DCI in reproductive conditions, the 40:1 combination of MI/DCI in PCOS. Furthermore, we discuss the issues of insulin resistance and how α-lactalbumin may increase the intestinal bioavailability of MI. The paper then transitions to talk about the use of inositols in diabetes, including type II diabetes, Gestational Diabetes Mellitus (GDM), and double diabetes. Literature searches were performed with the use of PubMed, Google Scholar, and Web of Science between July and October 2023. EXPERT OPINION: Inositol therapy has grown in the clinical field of PCOS, with it demonstrating an efficacy like that of metformin. The use of α-lactalbumin has further supported the use of MI, as issues with intestinal bioavailability have been largely overcome. In contrast, the effect of inositol treatment on the different PCOS phenotypes remains an outstanding question. The use of inositols in type II diabetes requires further study despite promising analogous data from GDM.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Resistência à Insulina , Síndrome do Ovário Policístico , Gravidez , Feminino , Humanos , Inositol/farmacologia , Inositol/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Lactalbumina/uso terapêutico
7.
Int J Biol Macromol ; 254(Pt 1): 127751, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287593

RESUMO

In order to meet the market demand and avoid the increase of operation amount and cleaning cost in the process of ultrafiltration, it is particularly important to find more practical and efficient methods to control and improve membrane fouling. In this study, the ions in the ultrafiltration process were regulated to affect membrane surface proteins composition (lactoferrin, α-lactalbumin, ß-lactoglobulin A and ß-lactoglobulin B) and delay membrane fouling. It was found that Na+ (21 mmol/L), Zn2+ (0.25 mmol/L) and K+ (44 mmol/L) was added at 4 min, 8 min and 12 min, respectively during ultrafiltration process. The continuous regulation slowed down the decline rate of membrane flux and reduced the content of α-lactalbumin, ß-lactoglobulin A and ß-lactoglobulin B on the membrane surface analyzed by HPLC. This could reduce the irreversible membrane fouling of proteins cake resistance. Furthermore, the ions concentration was also investigated after filtration. The concentration of K+ was increased significantly and other ions concentration was not significantly changed after continuous regulation such Na+, Mg2+, Zn2+ and Ca2+ compared to control. Therefore, dynamic ionic regulation of whey protein ultrafiltration process is a simple and effective method, which provides technical theoretical basis for optimizing and improving membrane technology.


Assuntos
Ultrafiltração , Purificação da Água , Ultrafiltração/métodos , Proteínas do Soro do Leite , Lactalbumina , Cromatografia Líquida de Alta Pressão , Lactoglobulinas , Proteínas de Membrana , Fatores de Transcrição , Íons , Membranas Artificiais , Purificação da Água/métodos
8.
Int J Biol Macromol ; 254(Pt 2): 127908, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939780

RESUMO

Amyloid fibrils are self-assembled aggregates of proteins and peptides that can lead to a broad range of diseases called amyloidosis. So far, no definitive and approved treatment to target directly amyloid fibrils has been introduced. Nevertheless, the search for small molecules with ability to inhibit and suppress fibril formation is an active and promising area of the research. Herein, the binding interactions and inhibitory effects of myricetin and morin hydrate on the in vitro fibrillation of bovine α-lactalbumin (BLA) have been investigated. The intrinsic fluorescence of BLA was quenched by myricetin and morin hydrate through combination of the static and dynamic quenching along with non-radiative Förster energy transfer mechanisms. The binding of these two flavonoids to BLA were not accompanied by major alteration in the conformation of BLA as evidenced by CD studies. The results of the fluorescence quenching analyses indicated almost the same binding affinities of myricetin and morin hydrate toward BLA (Kb ~ 106 M-1). However, the results of thioflavin T (ThT) assays showed that myricetin is a stronger inhibitor against BLA fibrillation compared to morin hydrate.


Assuntos
Amiloide , Lactalbumina , Animais , Bovinos , Amiloide/química , Lactalbumina/química , Flavonoides/farmacologia , Flavonoides/química
9.
Food Chem ; 439: 138046, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029562

RESUMO

In this research, interactions between α-lactalbumin (ALA) and three protopanaxadiol ginsenosides [20(S)-Rg3, 20(S)-Rh2, and 20(S)-PPD] were compared to explore the effects of similar ligand on structure and cytotoxicity of ALA. Multi-spectroscopy revealed the binding between ALA and ginsenoside changed the conformation of ALA, which related to different structures and solubility of ligands. Scanning electron microscope illustrated that all ALA-ginsenoside complexes exhibited denser structures via hydrophobic interactions. Additionally, the cytotoxic experiments confirmed that the cytotoxicity of ginsenoside was enhanced after binding with ALA. Molecular docking showed all three ginsenosides were bound to the sulcus depression region of ALA via hydrogen bonding and hydrophobic interaction. Furthermore, molecular dynamics simulation elucidated the precise binding sites and pertinent system properties. Among all three composite systems, 20(S)-Rh2 had optimal binding affinity. These findings enhanced understanding of the synergistic utilization of ALA and ginsenosides as functional ingredients in food, medicine, and cosmetics.


Assuntos
Ginsenosídeos , Sapogeninas , Ginsenosídeos/farmacologia , Ginsenosídeos/química , Lactalbumina , Simulação de Acoplamento Molecular , Sapogeninas/química , Sapogeninas/farmacologia
10.
J Dairy Sci ; 107(2): 1068-1084, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38122895

RESUMO

α-Lactalbumin (α-LA), which is encoded by the LALBA gene, is a major whey protein that binds to Ca2+ and facilitates lactose synthesis as a regulatory subunit of the synthase enzyme complex. In addition, it has been shown to play central roles in immune modulation, cell-growth regulation, and antimicrobial activity. In this study, a multitechnical approach was used to fully characterize the LALBA gene and its variants in both coding and regulatory regions for domestic camelids (dromedary, Bactrian camel, alpaca, and llama). The gene analysis revealed a conserved structure among the camelids, but a slight difference in size (2,012 bp on average) due to intronic variations. Promoters were characterized for the transcription factor binding sites (11 found in total). Intraspecies sequence comparison showed 36 SNPs in total (2 in the dromedary, none in the Bactrian camel, 22 in the alpaca, and 12 in the llama), whereas interspecies comparison showed 86 additional polymorphic sites. Eight SNPs were identified as trans-specific polymorphisms, and 2 of them (g.112A>G and g.1229A>G) were particularly interesting in the New World camels. The first creates a new binding site for transcription factor SP1. An enhancing effect of the g.112G variant on the expression was demonstrated by 3 independent pGL3 gene reporter assays. The latter is responsible for the p.78Ile>Val AA replacement and represents novel allelic variants (named LALBA A and B). A link to protein variants has been established by isoelectric focusing (IEF), and bioinformatics analysis revealed that carriers of valine (g.1229G) have a higher glycosylation rate. Genotyping methods based on restriction fragment length polymorphism (PCR-RFLP) were set up for both SNPs. Overall, adenine was more frequent (0.54 and 0.76) at both loci. Four haplotypes were found, and the AA and GA were the most common with a frequency of 0.403 and 0.365, respectively. Conversely, a putative biological gain characterizes the haplotype GG. Therefore, opportunities for rapid directional selection can be realized if this haplotype is associated with favorable milk protein properties. This study adds knowledge at the gene and protein level for α-LA (LALBA) in camelids and importantly contributes to a relatively unexplored research area in these species.


Assuntos
Camelídeos Americanos , Lactalbumina , Animais , Lactalbumina/genética , Camelus/genética , Alelos , Camelídeos Americanos/genética , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética
11.
Anal Chem ; 95(43): 15861-15866, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37857348

RESUMO

Transport within human tissue matrices, e.g., the subcutaneous tissue, exhibits some resemblance to chromatographic processes. Here, a porous matrix comprising agarose beads compatible with UV-vis imaging was developed for a parallel piped rectangular flow cell (4 mm light path). Introduction of high-molecular weight dextrans (Mr ∼ 200000 and ∼500000) at 10% (w/v) rendered imaging possible by providing optical clearing of the turbid porous matrix, resulting in improved transmittance as well as resolution (from 400 to 180 µm) at 280 nm, as well as 520 nm. The interplay between diffusive and convective transport at 0 < Pe ≤ 28 was visualized at 280 nm upon injection of dexamethasone suspensions. Real-time UV-vis imaging showed in-flow cell the effect of incorporating ion-exchange resins on the retention of infliximab, lysozyme, and α-lactalbumin. The ion-exchange matrix may serve as a surrogate for polyelectrolytes in the subcutaneous tissue, assessing the potential role of electrostatic interactions of biotherapeutics upon injection. UV-vis imaging of size-exclusion chromatographic matrixes may be of interest in its own right and potentially develop into a characterization tool for injectables.


Assuntos
Lactalbumina , Tela Subcutânea , Humanos , Cromatografia por Troca Iônica/métodos
12.
Int J Biol Macromol ; 253(Pt 7): 127374, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37839609

RESUMO

As an opaque and complex colloidal mixture, milk is usually present as a positively charged colloid under acidic conditions. Adding negatively charged colloids can lead to protein aggregation in milk. Alpha-lactalbumin (α-La) is an essential component of whey protein and has good physicochemical properties for functional food development. We combined spectroscopy, computer simulations, and other techniques to comparative analyze the mechanisms and characteristics of isolated α-La aggregation induced by CI Acid Red 27 (C27)/CI Acid Red 14 (FB) containing different sulfonyl groups in vitro. The results showed that C27/FB (5.25 × 10-5 mol·L-1 to 3.15 × 10-4 mol·L-1) induced the formation of fibril-like aggregates under acidic conditions (pH 2.0 and 4.0) mainly benefit from hydrophobic and electrostatic forces. Weakening and redshift of α-La's characteristics negative peak were observed (208 nm to 218 nm) on circular dichroism. ß-Crosslinks self-assembly and reorganization of disulfide bonds occurred during protein fibrillation. Moreover, the different redshift intensity of Congo red binding to amyloid fibrils was observed to be induced by C27 (>551 nm) and FB (>536 nm), and the direct observation by TEM demonstrated the ability to induce protein fibrillation is C27 > FB. Edible azo dyes with more sulfonyl groups would possess a stronger ability to induce protein fibrillation.


Assuntos
Lactalbumina , Leite , Animais , Lactalbumina/química , Proteínas do Soro do Leite , Leite/metabolismo , Dicroísmo Circular , Compostos Azo , Amiloide/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-37657402

RESUMO

Liquid chromatography coupled with mass spectrometry is widely used in the field of proteomic analysis after off-line protein digestion. On-line digestion with chromatographic column connected in a series with immobilized enzymatic reactor is not often used approach. In this work we investigated the impact of chromatographic conditions on the protein digestion efficiency. The investigation of trypsin reactor activity was performed by on-line digestion of N-α-benzoyl-L-arginine 4-nitroanilide hydrochloride (BAPNA), followed by separation of the digests on the mixed-mode column. Two trypsin column reactors with the different trypsin coverage on the bridged ethylene hybrid particles were evaluated. To ensure optimal trypsin activity, the separation temperature was set at 37.0 °C and the pH of the mobile phase buffer was maintained at 8.5. The on-line digestion itself ongoing during the initial state of gradient was carried out at a low flow rate using a mobile phase that was free of organic modifiers. Proteins such as cytochrome C, enolase, and myoglobin were successfully digested on-line without prior reduction or alkylation, and the resulting peptides were separated using a mixed-mode column. Additionally, proteins that contain multiple cysteines, such as α-lactalbumin, albumin, ß-lactoglobulin A, and conalbumin, were also successfully digested on-line (after reduction and alkylation). Moreover, trypsin immobilized enzymatic reactors were utilized for over 300 injections without any noticeable loss of digestion activity.


Assuntos
Lactalbumina , Proteômica , Proteólise , Tripsina , Alquilação , Enzimas Imobilizadas
14.
J Phys Chem B ; 127(33): 7251-7265, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37574910

RESUMO

Ionic liquids (ILs) are known to stabilize protein conformations in aqueous medium. Importantly, ILs can also act as refolding additives in urea-driven denaturation of proteins. However, despite the importance of the problem, detailed microscopic understanding of the counteraction effects of ILs on urea-induced protein denaturation remains elusive. In this work, atomistic molecular dynamics (MD) simulations of the protein α-lactalbumin have been carried out in pure aqueous medium, in 8 M binary urea-water solution and in ternary urea-IL-water solutions containing ammonium-based ethyl ammonium acetate (EAA) as the IL at different concentrations (1-4 M). Attempts have been made to quantify detailed molecular-level understanding of the origin behind the counteraction effects of the IL on urea-induced partial unfolding of the protein. The calculations revealed significant conformational changes of the protein with multiple free energy minima due to its partial unfolding in binary urea-water solution. The counteraction effect of the IL was evident from the enhanced structural rigidity of the protein with propensity to transform into a single native free energy minimum state in ternary urea-IL-water solutions. Such an effect has been found to be associated with preferential direct binding of the IL components with the protein and simultaneous expulsion of urea from the interface, thereby providing additional stabilization of the protein in ternary solutions. Most importantly, modified rearrangement of the hydrogen bond network at the interface due to the formation of stronger protein-cation (PC) and protein-anion (PA) hydrogen bonds by breaking relatively weaker protein-urea (PU) and protein-water (PW) hydrogen bonds has been recognized as the microscopic origin behind the counteraction effects of EAA on urea-induced partial unfolding of the protein.


Assuntos
Compostos de Amônio , Líquidos Iônicos , Líquidos Iônicos/química , Lactalbumina , Peptídeos/química , Ureia/farmacologia , Ureia/química , Simulação de Dinâmica Molecular , Água/química , Fatores de Transcrição , Desnaturação Proteica
15.
Colloids Surf B Biointerfaces ; 230: 113490, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37556880

RESUMO

In order to highlight the role of hydrophobic interactions in the molten globule (MG) state of globular protein modulated by surfactants, the interactions of bovine α-lactalbumin (α-LA) with alkyl trimethylammonium bromides (CnTAB, n = 10, 12, 14, and 16) have been studied by experimental and theoretical techniques. Isothermal titration calorimetry (ITC) showed that the enthalpy changes (ΔH) and area of the enthalpogram increased with increasing the chain length of CnTAB. The result of fluorescence, circular dichroism (CD) and 1H nuclear magnetic resonance (NMR) spectrum suggested that C10TAB and C12TAB unfolded α-LA partially, C14TAB reconstructed protein with a native-like secondary structure content, and C16TAB induced an MG state α-LA. The SAXS results confirmed that the tertiary structure of α-LA was disrupted by C16TAB forming an MG state complex with a micelle-like structure even at the surfactants concentrations below CMC. As indicated by MD results, the ß-domain and unstructured region(s) were involved in the MG state α-LA modulated by CnTAB. This work not only provides molecular insights into the role of hydrophobic interactions in the MG state of a globular protein but also helps understand the mechanism of preparing α-LA based biomacromolecule modulated by hydrophobic interactions.


Assuntos
Dobramento de Proteína , Tensoativos , Animais , Bovinos , Espalhamento a Baixo Ângulo , Difração de Raios X , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Lactalbumina/química
16.
J Dairy Sci ; 106(12): 8321-8330, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641337

RESUMO

Protein lactosylation is a significant modification that occurs during the heat treatment of dairy products, causing changes in proteins' physical-chemical and nutritional properties. Knowledge of the detailed lactosylation information on milk proteins under various heat treatments is important for selecting appropriate thermo-processing and identifying markers to monitor heat load in dairy products. In the present study, we used proteomics techniques to investigate lactosylated proteins under different heating temperatures. We observed a total of 123 lactosylated lysines in 65 proteins, with lactosylation even occurring in raw milk. The number of lactosylated lysines and proteins increased moderately at 75°C to 130°C, but dramatically at 140°C. We found that 6 out of 10, 9 out of 16, 6 out of 12, and 5 out of 15 lysine residues in κ-casein, ß-lactoglobulin, α-lactalbumin, and αS1-casein, respectively, were lactosylated under the applied heating treatment. Moreover, different lactosylation states of individual lysines and proteins can indicate the intensity of heating processes. Lactosylation of K14 in ß-lactoglobulin could distinguish pasteurized and UHT milk, while lactosylation of lactotransferrin can reflect moderate heat treatment of products.


Assuntos
Temperatura Alta , Proteínas do Leite , Animais , Proteínas do Leite/análise , Lactalbumina/análise , Leite/química , Caseínas/química , Lactoglobulinas/química , Proteínas do Soro do Leite/análise
17.
Eur Rev Med Pharmacol Sci ; 27(12): 5831-5840, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37401320

RESUMO

The present review focuses on the side effects that ex-obese patients face following bariatric surgery. We searched through the principal medical indexes (SCOPUS, Web of Science, PubMed, MEDLINE) using the following words, both alone and in combinations: bariatrics; bariatric surgery; anemia; vitamin B12; cobalamin; folate; folic acid; iron; iron supplements; gut microbiota; lactalbumin; α-lactalbumin. To perform exhaustive research, we considered articles published since 1985. Bariatric surgery induces states of nutritional deficiencies. In particular, the surgery results in a drastic fall in the levels of iron, cobalamin, and folate. Despite the dietary supplements which can counteract such decrease, some limitations exist in the nutraceutical approach. Indeed, the gastrointestinal side effects of supplements, the alterations in the microbiota, and the reduced absorption induced by the surgery may impair the effect of dietary supplements, exposing the patients to the risk of developing nutritional deficiencies. Recent literature reports the effect of promising molecules to counteract such limitations, which include α-lactalbumin, a whey protein with prebiotic activities, and new pharmaceutical forms of iron supplements, namely micronized ferric pyrophosphate. If on the one hand, α-lactalbumin enhances intestinal absorption and helps in restoring a physiological microbiota, micronized ferric pyrophosphate has a high tolerability and low or null risk of gastrointestinal side effects. Bariatric surgery represents a valid solution to obesity and obesity-related disease. However, the procedure may induce deficiencies in micronutrients. Data exists on the promising activities of α-lactalbumin and micronized ferric pyrophosphate, which may help in preventing bariatric-induced anemia.


Assuntos
Anemia , Cirurgia Bariátrica , Desnutrição , Obesidade Mórbida , Humanos , Lactalbumina , Ferro , Cirurgia Bariátrica/efeitos adversos , Obesidade/cirurgia , Obesidade/etiologia , Ácido Fólico , Suplementos Nutricionais , Vitamina B 12 , Obesidade Mórbida/cirurgia
18.
Food Chem ; 427: 136752, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37392621

RESUMO

The oleic acid/alpha-lactalbumin complex HAMLET (human alpha-lactalbumin made lethal to tumors) is cytotoxic to various cancerous cell lines and is assembled from alpha-lactalbumin (ALA) and free oleic acid (OA). HAMLET is also cytotoxic to normal immature intestinal cells. It remains unclear if HAMLET, experimentally assembled with OA and heat, can spontaneously assemble in frozen human milk over time. To approach this issue, we used a set of timed proteolytic experiments to evaluate the digestibility of HAMLET and native ALA. The purity of HAMLET in human milk was confirmed by ultra high performance liquid chromatography coupled to tandem mass spectrometry and western blot to resolve the ALA and OA components. Timed proteolytic experiments were used to identify HAMLET in whole milk samples. Structural characterization of HAMLET was performed by Fournier transformed infrared spectroscopy and indicated a transformation of secondary structure with increased alpha-helical character of ALA upon binding to OA.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Ácido Oleico/química , Leite Humano/metabolismo , Lactalbumina/química , Neoplasias/patologia , Antineoplásicos/química , Digestão , Ácidos Oleicos/química
19.
Nutrients ; 15(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513560

RESUMO

The primary control of dysmetabolic patients is extremely challenging worldwide, with inadequate dietary habits and sporadic physical activity among the key risk factors for metabolic syndrome onset. Nowadays, there is no exclusive treatment for this condition, and considering that preventive measures usually fail, new therapeutic approaches need to be proposed and investigated. This present pilot study compared the effects of diet alone and in association with a combination of myo-inositol and d-chiro-inositol in their 40:1 ratio, α-lactalbumin, and Gymnema sylvestre on different metabolic parameters in obese dysmetabolic patients. To this purpose, 37 patients with BMI between 30 and 40 and fasting blood glucose between 100 and 125 mg/dL were divided into two groups: (i) the control group followed a hypocaloric Mediterranean diet, (ii) while the study group was also supplemented with a daily dosage of two sachets, each one containing 1950 mg myo-inositol, 50 mg d-chiro-inositol, 50 mg α-lactalbumin, and 250 mg Gymnema Sylvestre. After a 6-month treatment, all parameters improved in both groups. Nevertheless, the treated group experienced a greater improvement, especially concerning the variation from the baseline of HOMA index, triglycerides, BMI, body weight, and waist circumference. These findings support the supplementation with myo-inositol and d-chiro-inositol in the 40:1 ratio, α-lactalbumin, and Gymnema sylvestre as a therapeutical strategy to potentiate the beneficial effects induced via dietary programs in dysmetabolic patients.


Assuntos
Gymnema sylvestre , Síndrome do Ovário Policístico , Humanos , Feminino , Lactalbumina/metabolismo , Inositol/uso terapêutico , Projetos Piloto , Dieta , Obesidade/complicações , Obesidade/tratamento farmacológico , Peso Corporal , Metaboloma
20.
Pediatr Allergy Immunol Pulmonol ; 36(3): 90-93, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37433203

RESUMO

Objective: Cases of cow's milk allergy (CMA) who reacted to measles or measles, mumps, and rubella (MMR) vaccines containing alpha-lactalbumin have been reported. The purpose of this study was to assess patients with CMA who received measles or MMR vaccines containing alpha-lactalbumin, as well as the characteristics of those who developed reactions to these vaccines. Study Design: Patients followed up in the allergy clinic for CMA and who received measles or MMR vaccines containing alpha-lactalbumin at 9 or 12 months of age were included in the study, and their characteristics were analyzed retrospectively from the hospital registry system. Results: Forty-nine patients were included in the study. Six patients received the measles vaccine, whereas 43 patients received the MMR vaccine containing alpha-lactalbumin. Vaccine skin tests were performed on these 6 patients. One patient had a positive intradermal test, so an alternative vaccine not containing alpha-lactalbumin was administered. The other 5 patients were vaccinated, and no reaction was observed. Anaphylaxis was observed in 3 of 43 patients who received the MMR vaccine containing alpha-lactalbumin. In all of these patients, the first reaction to dairy products was anaphylaxis. In 2 of those patients, cow's milk-specific IgE (spIgE) levels were >100 kU/L, and alpha-lactalbumin-spIgE levels were also high at 97 and 90 kU/L. The third patient's cow's milk-spIgE level was 15.9 kU/L, whereas the alpha-lactalbumin-spIgE level was 0.04 kU/L. Conclusion: Especially in patients with an initial reaction of anaphylaxis to dairy products and high cow's milk-spIgE levels, the risk of reaction is high with the MMR vaccine.


Assuntos
Anafilaxia , Lactalbumina , Vacina contra Sarampo-Caxumba-Rubéola , Hipersensibilidade a Leite , Leite , Animais , Bovinos , Feminino , Anafilaxia/imunologia , Imunoglobulina E , Lactalbumina/efeitos adversos , Lactalbumina/imunologia , Vacina contra Sarampo-Caxumba-Rubéola/efeitos adversos , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Hipersensibilidade a Leite/imunologia , Estudos Retrospectivos , Humanos , Leite/efeitos adversos , Leite/imunologia
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