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Nutrients Jan 2024Shifts toward increased proteolytic fermentation, such as, for example, in athlete and high-protein weight loss diets, may alter the relative abundance of microbial...
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 () protein isolates (chickpea protein isolate (CPI), lupin protein isolate (LI)). ANOSIM and Discriminant Analysis showed significant ( < 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 ( < 0.05) for predicted functionality parameters as determined by PICRUSt analysis. LA induced a generally healthier microbiota composition than CAS, and higher amounts of 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.
Topics: Humans; Animals; Rats; Gastrointestinal Microbiome; Milk; Diet; Microbiota; Vegetables; Caseins; Lactalbumin; Cicer; Fabaceae; Legumins
PubMed: 38201979
DOI: 10.3390/nu16010149 -
Foods (Basel, Switzerland) Jan 2024Protein content variation in milk can impact the quality and consistency of dairy products, necessitating access to in-line real time monitoring. Here, we present a...
Protein content variation in milk can impact the quality and consistency of dairy products, necessitating access to in-line real time monitoring. Here, we present a chemometric approach for the qualitative and quantitative monitoring of β-lactoglobulin and α-lactalbumin, using mid-infrared spectroscopy (MIR). In this study, we employed Hotelling T2 and Q-residual for outlier detection, automated preprocessing using nippy, conducted wavenumber selection with genetic algorithms, and evaluated four chemometric models, including partial least squares, support vector regression (SVR), ridge, and logistic regression to accurately predict the concentrations of β-lactoglobulin and α-lactalbumin in milk. For the quantitative analysis of these two whey proteins, SVR performed the best to interpret protein concentration from 197 MIR spectra originating from 42 Cornell University samples of preserved pasteurized modified milk. The R values obtained for β-lactoglobulin and α-lactalbumin using leave one out cross-validation (LOOCV) are 92.8% and 92.7%, respectively, which is the highest correlation reported to date. Our approach introduced a combination of preprocessing automation, genetic algorithm-based wavenumber selection, and used Optuna to optimize the framework for tuning hyperparameters of the chemometric models, resulting in the best chemometric analysis of MIR data to quantitate β-lactoglobulin and α-lactalbumin to date.
PubMed: 38201194
DOI: 10.3390/foods13010166 -
BioRxiv : the Preprint Server For... Feb 2024Human milk contains extracellular vesicles (HMEVs). Pre-clinical models suggest that HMEVs may enhance intestinal function and limit inflammation; however, it is unknown...
Human milk contains extracellular vesicles (HMEVs). Pre-clinical models suggest that HMEVs may enhance intestinal function and limit inflammation; however, it is unknown if HMEVs or their cargo survive neonatal human digestion. This limits the ability to leverage HMEV cargo as additives to infant nutrition or as therapeutics. This study aimed to develop an EV isolation pipeline from small volumes of human milk and neonatal intestinal contents after milk feeding (digesta) to address the hypothesis that HMEVs survive in vivo neonatal digestion to be taken up intestinal epithelial cells (IECs). Digesta was collected from nasoduodenal sampling tubes or ostomies. EVs were isolated from raw and pasteurized human milk and digesta by density-gradient ultracentrifugation following two-step skimming, acid precipitation of caseins, and multi-step filtration. EVs were validated by electron microscopy, western blotting, nanoparticle tracking analysis, resistive pulse sensing, and super-resolution microscopy. EV uptake was tested in human neonatal enteroids. HMEVs and digesta EVs (dEVs) show typical EV morphology and are enriched in CD81 and CD9, but depleted of β-casein and lactalbumin. HMEV and some dEV fractions contain mammary gland-derived protein BTN1A1. Neonatal human enteroids rapidly take up dEVs in part via clathrin-mediated endocytosis. Our data suggest that EVs can be isolated from digestive fluid and that these dEVs can be absorbed by IECs.
PubMed: 38187651
DOI: 10.1101/2023.09.03.556067 -
Asian Pacific Journal of Allergy and... Jan 2024Cow's milk allergy (CMA) is one of the most common food allergies in young children. As improved diagnostic tools, allergic tests are inconsistent and limited in...
BACKGROUND
Cow's milk allergy (CMA) is one of the most common food allergies in young children. As improved diagnostic tools, allergic tests are inconsistent and limited in predicting anaphylaxis.
OBJECTIVE
To explore risk factors for anaphylaxis and to determine practical cut-offs for allergic tests in predicting anaphylaxis.
METHODS
This is a prospective cohort study. Children with IgE-mediated CMA were enrolled and divided into three groups (Group 1: non-anaphylaxis; Group 2: GRADE I anaphylaxis; Group 3: GRADE II-IV anaphylaxis that warranted epinephrine). Prick-to-prick tests (PTPs) using fresh cow's milk (CM) were performed. Serum specific IgE (sIgE) against CM and its components, including casein, alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin were measured. The 90% and 95% positive predictive value (PPV) decision points for predicting anaphylaxis were determined. Potential predictors of anaphylaxis were evaluated in logistic regression models.
RESULTS
This study included 134 CMA patients with a median age of 14.4 months. The sensitization rate to any CM component was 89%. Group 3 was more likely to be sensitized to multiple CM components and have higher sIgE levels. The 95% PPV diagnostic decision points of casein-sIgE in predicting anaphylaxis was 13.0 kUA/L. For GRADE II-IV anaphylaxis, casein-sIgE ≥ 54.9 kUA/L could provide a PPV of 88.9%. The elevated casein-sIgE level (OR 14.0, P=0.025) and complicating respiratory allergic diseases (OR 4.8, P=0.022) were independent risk factors for GRADE II-IV anaphylaxis.
CONCLUSION
High casein-sIgE levels are strongly associated with CM anaphylaxis. Detection of casein-sIgE may offer an additional value for the prediction of CM anaphylaxis.
PubMed: 38183641
DOI: 10.12932/AP-010823-1667 -
Molecules (Basel, Switzerland) Dec 2023Fermented dairy products (e.g., yogurt, kefir, and buttermilk) are significant in the dairy industry. They are less immunoreactive than the raw materials from which they... (Review)
Review
Fermented dairy products (e.g., yogurt, kefir, and buttermilk) are significant in the dairy industry. They are less immunoreactive than the raw materials from which they are derived. The attractiveness of these products is based on their bioactivity and properties that induce immune or anti-inflammatory processes. In the search for new solutions, plant raw materials with beneficial effects have been combined to multiply their effects or obtain new properties. Polyphenols (e.g., flavonoids, phenolic acids, lignans, and stilbenes) are present in fruit and vegetables, but also in coffee, tea, or wine. They reduce the risk of chronic diseases, such as cancer, diabetes, or inflammation. Hence, it is becoming valuable to combine dairy proteins with polyphenols, of which epigallocatechin-3-gallate (EGCG) and chlorogenic acid (CGA) show a particular predisposition to bind to milk proteins (e.g., α-lactalbumin β-lactoglobulin, αs1-casein, and κ-casein). Reducing the allergenicity of milk proteins by combining them with polyphenols is an essential issue. As potential 'metabolic prebiotics', they also contribute to stimulating the growth of beneficial bacteria and inhibiting pathogenic bacteria in the human gastrointestinal tract. In silico methods, mainly docking, assess the new structures of conjugates and the consequences of the interactions that are formed between proteins and polyphenols, as well as to predict their action in the body.
Topics: Humans; Phenols; Polyphenols; Flavonoids; Cultured Milk Products; Milk Proteins
PubMed: 38138571
DOI: 10.3390/molecules28248081 -
Journal of Clinical Medicine Dec 2023Type 2 diabetes mellitus (T2DM) is characterized by high blood glucose levels and lipid alterations. Besides pharmacological treatment, lifestyle modifications and...
Type 2 diabetes mellitus (T2DM) is characterized by high blood glucose levels and lipid alterations. Besides pharmacological treatment, lifestyle modifications and nutraceuticals can be used to manage glucose and lipid profiles, which is crucial for preventing, or avoiding, serious consequences associated with the condition. This randomized controlled clinical trial on 75 patients with T2DM evaluated the effects of a combination of myo-inositol and d-chiro-inositol (40:1), α-lactalbumin, Gymnema sylvestre, and zinc on glucose and lipid profile. The intention-to-treat analysis displayed no significant differences in glucose parameters between the groups; however, the study group displayed reduced levels of total cholesterol ( = 0.01) and LDL ( = 0.03) after 3 months of supplementation. A subgroup analysis involving patients who did not modify their antidiabetic therapy, after 6 months displayed improved levels of total cholesterol ( = 0.03) and LDL ( = 0.04) in the study group versus placebo, along with a greater body weight reduction ( = 0.03) after 3 months. Furthermore, within the study group, levels of HDL ( = 0.03) and triglycerides ( = 0.04) improved after 3 months. These findings support supplementation with myo-inositol and d-chiro-inositol (40:1), α-lactalbumin, Gymnema sylvestre, and zinc as an adjuvant and safe strategy to manage the lipid profiles of patients with T2DM.
PubMed: 38137721
DOI: 10.3390/jcm12247650 -
Cureus Dec 2023Cow's milk protein allergies (CMPAs) particularly occur in infancy and early childhood due to an immunological allergic reaction to milk proteins. This issue is...
Cow's milk protein allergies (CMPAs) particularly occur in infancy and early childhood due to an immunological allergic reaction to milk proteins. This issue is increasing in Saudi Arabia and requires research to improve health status and provide alternatives. Our study aims to investigate the important aspects of immunoglobulin E (IgE) and IgG CMPA in Saudi Arabia regarding its prevalence and association with demographic and health-related factors in both adult and pediatric populations. A descriptive retrospective cross-sectional study was conducted on 376 patients, comprising 314 adults aged between 19 and 86 years, and 62 pediatric patients aged between one and 12 years. The study focused on individuals who attended a private medical center in Jeddah city over the past five years. Laboratory results for food allergy of IgE and IgG tests, including cow's milk proteins (CMPs), serum 25-hydroxyvitamin D (25OHD), specific IgE inhalant allergy results, and other health-related factors were collected from an electronic record system. Results have shown that casein was the most common sensitizing allergen of CMPs in adults, whereas α-lactalbumin was the most common sensitizing allergen in pediatrics. The most frequent sensitizing allergen in IgG CMP was cow's milk in 54/92 (58.7%) adults, followed by cow's sour milk products 41 (44.6%). Cow's milk was the most common sensitizing allergen in 20/20 (100%) children. The rate of CMPA was significantly higher in children younger than five years old ( =0.003), while children who interacted with pets had a marginal significantly reduced rate ( = 0.054). Thus, cow's milk is the most sensitizing allergen in IgG CMPs in adults and pediatrics.
PubMed: 38125695
DOI: 10.7759/cureus.50812 -
Journal of Dairy Science Feb 2024α-Lactalbumin (α-LA), which is encoded by the LALBA gene, is a major whey protein that binds to Ca and facilitates lactose synthesis as a regulatory subunit of the...
Genetic variability among and within domestic Old and New World camels at the α-lactalbumin gene (LALBA) reveals new alleles and polymorphisms responsible for differential expression.
α-Lactalbumin (α-LA), which is encoded by the LALBA gene, is a major whey protein that binds to Ca 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.
Topics: Animals; Lactalbumin; Camelus; Alleles; Camelids, New World; Polymorphism, Single Nucleotide; Transcription Factors
PubMed: 38122895
DOI: 10.3168/jds.2023-23813 -
Antibodies (Basel, Switzerland) Nov 2023In Spain, IgE-mediated cow's milk protein allergy (CMPA) affects approximately 0.69% of infants. Molecular diagnosis may be useful for monitoring natural spontaneous...
BACKGROUND
In Spain, IgE-mediated cow's milk protein allergy (CMPA) affects approximately 0.69% of infants. Molecular diagnosis may be useful for monitoring natural spontaneous tolerance development in CMPA. The aim of this study was to retrospectively analyse a cohort of paediatric patients with IgE-mediated CMPA who were avoiding milk products awaiting natural tolerance and determine the relationship between disease persistence and major cow's milk allergens.
METHODS
A retrospective chart review of 200 patients diagnosed with IgE-mediated CMPA between 2011 and 2020 was conducted. Patients strictly avoided milk products until an oral food challenge was performed. The main outcome was the introduction of liquid milk following a negative oral food challenge and its correlation with IgE and SPT measurements of milk components at diagnosis. Secondary outcomes included the rate of allergic reactions and anaphylaxis during the treatment period and its correlation with IgE and SPT measurements.
RESULTS
Of the 200 charts analysed, 122 patients had a negative oral food challenge to milk (61.0%) (95% confidence interval (CI): 54.1-67.5) following a period of strict avoidance of milk. Higher levels of component-specific IgE, especially casein, were associated with failure in the oral food challenge ( = 0.02). Allergic reactions were experienced by 106 children (53%), of which 34 (17%; 95% CI: 12.4-22.8) had anaphylactic reactions. The risk of anaphylaxis was not predicted by raised IgE levels.
CONCLUSIONS
While a large proportion of children acquired natural tolerance to cow's milk following a period of strict avoidance, IgE-mediated CMPA persisted in many children. Casein IgE levels at diagnosis were raised in those who failed to achieve natural tolerance. Allergic reactions to milk, including anaphylaxis, occurred commonly, but this was not predicted by raised IgE levels or SPT measurements.
PubMed: 37987254
DOI: 10.3390/antib12040076 -
Journal of Dairy Science Apr 2024Xanthine oxidase (XO), a rate-limiting enzyme in uric acid production, is the pivotal therapeutic target for gout and hyperuricemia. In this study, 57 peptides from...
Xanthine oxidase (XO), a rate-limiting enzyme in uric acid production, is the pivotal therapeutic target for gout and hyperuricemia. In this study, 57 peptides from α-lactalbumin and β-lactoglobulin were obtained via virtual enzymatic hydrolysis, and 10 XO inhibitory peptides were virtually screened using molecular docking. Then toxicity, allergenicity, solubility, and isoelectric point of the obtained 10 novel peptides were evaluated by in silico tools. The XO activity of these synthetic peptides was tested using an in vitro assay by high-performance liquid chromatography. Their inhibitory mechanism was further explored by molecular docking. The results showed that 4 peptides GL, PM, AL, and AM exhibited higher inhibitory activity, and their half maximal inhibitory concentration in vitro was 10.20 ± 0.89, 23.82 ± 0.94, 34.49 ± 0.89, and 40.45 ± 0.92 mM, respectively. The peptides fitted well with XO through hydrogen bond, hydrophobic interaction, and van der Waals forces, and amino acid residues Glu802, Leu873, Arg880, and Pro1076 played an important role in this process. Overall, this study indicated 4 novel peptides GL, PM, AL, and AM from whey protein exhibited XO inhibitory activity, and they might be useful and safe XO inhibitors for hyperuricemia prevention and treatment.
Topics: Animals; Gout Suppressants; Hyperuricemia; Xanthine Oxidase; Whey Proteins; Molecular Docking Simulation; Enzyme Inhibitors; Peptides
PubMed: 37923199
DOI: 10.3168/jds.2023-24028