Splenic gene expression of cytokines at multiple time points following lipopolysaccharide challenge in layers.

OBJECTIVE: To investigate inflammatory responses to lipopolysaccharide (LPS) injection in layers. ANIMALS: 33 40-week-old laying hens were used. METHODS: 30 laying hens were divided into 2 groups: the first group was injected with 8 mg/kg LPS, while the second group was injected with sterile saline. At the start of the study, 3 birds served as a baseline and were used as the time 0 controls for both the saline and LPS-treated groups. Blood and spleen tissues were collected at 0 (before) and 1, 2, 3, 4, and 6 hours after injection. RESULTS: LPS administration increased splenic mRNA levels of IL-1ß, IL-2, IL-6, IL-8, IL-10, interferon-γ, and tumor necrosis factor-α (P < .001) and serum IL-6 levels (P < .01) compared to saline injection. The mRNA expression of most cytokine genes increased rapidly toward peak values within 2 hours after the LPS injection, and then the difference between the saline and LPS treatments got smaller as time went on; serum IL-6 reached its highest concentration 2 hours after LPS administration. The magnitude of LPS-induced upregulation of gene expression was the highest for IL-6, followed by IL-1ß and IL-8, and tumor necrosis factor-α was the least affected. CLINICAL RELEVANCE: The temporal and quantitative profile of these inflammatory mediators generated from this study provides valuable information in identifying the optimal time window and appropriate biomarkers for LPS-induced inflammation, which has significant implications in evaluating the effects of interventions on the immune system of chickens.

Adding pulse flours to cereal-based snacks and bakery products: An overview of free asparagine quantification methods and mitigation strategies of acrylamide formation in foods.

Thermal processing techniques can lead to the formation of heat-induced toxic substances. Acrylamide is one contaminant that has received much scientific attention in recent years, and it is formed essentially during the Maillard reaction when foods rich in carbohydrates, particularly reducing sugars (glucose, fructose), and certain free amino acids, especially asparagine (ASN), are processed at high temperatures (>120°C). The highly variable free ASN concentration in raw materials makes it challenging for food businesses to keep acrylamide content below the European Commission benchmark levels, while avoiding flavor, color, and texture impacts on their products. Free ASN concentrations in crops are affected by environment, genotype, and soil fertilization, which can also influence protein content and amino acid composition. This review aims to provide an overview of free ASN and acrylamide quantification methods and mitigation strategies for acrylamide formation in foods, focusing on adding pulse flours to cereal-based snacks and bakery products. Overall, this review emphasizes the importance of these mitigation strategies in minimizing acrylamide formation in plant-based products and ensuring safer and healthier food options.

Options for substantiating protein content claims for conventional foods.

In Canada and the United States, front-of-package protein content claims require data to support the quality of the protein. In general, protein quality reflects the product of the amino acid composition of the food protein relative to human amino acid requirements and a measure of digestibility. The currently accepted method in both jurisdictions is the protein digestibility-corrected amino acid score (PDCAAS) that requires the measurement of true fecal protein (nitrogen) digestibility. The latter must be measured in vivo using a rat model. This requirement for animal testing is inconsistent with international efforts to reduce the usage of animals in testing for regulatory purposes. The current commentary positions four options to remove the need to use animal testing for determining protein quality, when considering protein content claim substantiation. These options include (i) a focus on protein quantity alone; (ii) the use of the amino acid score alone, with no correction for digestibility; (iii) the use of a fixed digestibility coefficient to estimate protein quality; and (iv) the use of in vitro methods to measure protein and/or amino acid digestibility. The relative merits and deficiencies of the options are positioned with the goal of encouraging dialogue within the regulatory agencies to move towards alternative approaches for substantiating protein content claims on foods, including those derived from plant-based sources.

Impact of cooking on the protein quality of Russet potatoes.

Despite being low in crude protein, on a fresh weight basis, given their overall contribution to the North American diet, potatoes contribute approximately 2%-4% of the population's protein intake. However, the quality of the protein remains ill-defined. To that end, Russet potatoes were secured and subjected to various cooking conditions (raw [control], boiled, baked, microwaved, and fried [3, 6, and 9 min]) to determine the impact of cooking method on protein quality, as determined by amino acid score (AAS) and indices of in vivo true fecal protein digestibility (TFPD%; rodent bioassay) and in vitro protein digestibility (pH-drop, pH-Stat, and simulated gastrointestinal digestion both static and dynamic). The AAS of raw Russet potatoes was 0.67 ± 0.01, with histidine being the limiting AA. Frying led to a significant reduction in the AAS, however, other cooking methods yielded similar results to the raw control. The TFPD% of raw potato was low (40.5% ± 3.9%) and was significantly enhanced to over 80% with all cooking methods. Similar patterns were observed with all in vitro measures, however, all methods yielded higher values for the raw control samples. Final protein digestibility-corrected AAS (PDCAAS; product of AAS and TFPD%) values ranged from 0.27 (raw) to a high of 0.57 (boiled), with cooked values being comparable to other plant-based protein sources, including grains, and some nuts and pulses. In vitro PDCAAS values followed similar trends. This study defined the protein quality of cooked Russet potatoes and provides data for use in defining the quality of total protein consumed in the North American diet.

The in vivo and in vitro protein quality of three hemp protein sources.

In this work, the protein quality of defatted hemp hearts and protein-enriched hemp fractions was determined. Protein quality was assessed using a rodent bioassay to evaluate growth and protein digestibility, while amino acid composition was determined via HPLC. A method for determining in vitro protein digestibility was compared to in vivo methodology and used to generate an in vitro protein quality score. The true protein digestibility of hemp protein 2, a hemp protein concentrate, was significantly lower than that of either defatted hemp hearts or hemp protein 1, a hemp protein concentrate (p < .05). While there was no relationship between the in vivo and in vitro measurements of protein digestibility (R 2 = .293, p = .459), there was a significant correlation between the protein digestibility-corrected amino acid score (PDCAAS) determined in vivo and in vitro PDCAAS (R 2 = .989, p = .005). The protein efficiency ratio of hemp protein 1 was significantly lower than that of either defatted hemp hearts or hemp protein 2 (p < .05). These data highlight the nutritional capacity of hemp protein sources while also demonstrating the relationship between in vivo and in vitro methods for determining protein quality.

Effects of genotype, environment and their interaction on protein and amino acid contents in soybeans.

Soybean [Glycine max (L.) Merr.] is an important source of protein and oil. Genotype, environment and the interaction of genotype × environment influence the protein composition in soybean seeds. The main objectives of this study were to i) study the influence of genotype, environment and their interaction on soybean protein and amino acid contents; ii) evaluate the stability of soybean genotype across various environments, with a focus on soybeans grown in a northern latitude; and iii) identify the correlation between crude protein and critical amino acid value (CAAV). Twenty-three soybean genotypes were grown at four locations in Manitoba, Canada for two years (2018 and 2019). Soybean seeds were analyzed for protein and amino acids (nine essential amino acids and cysteine). The effects of genotype, environment and genotype × environment interaction on all traits were significant (P < 0.05). Genotype and environments explained the main part of variation for all traits. G13 and G15 cultivars performed better in favorable environments (bi > 1), and G22 cultivar showed greater resistance to environmental change. Protein and amino acids responded differently to various environments, but the optimal environments for greater soybean protein and amino acid remains to be established. The CAAV had a negative linear relationship with protein content in soybean (k = -0.17). This work expands our knowledge of the factors impacting the protein quality of soybeans grown in northern latitudes.

Plant Proteins: Methods of Quality Assessment and the Human Health Benefits of Pulses.

As countries increase their standard of living and individual income levels rise, there is a concomitant increase in the demand for animal-based protein. However, there are alternative sources. One of the alternatives available is that of increased direct human consumption of plant proteins. The quality of a dietary protein is an important consideration when discussing the merits of one protein source over another. The three most commonly used methods to express protein quality are the protein efficiency ratio (PER), a weight gain measurement; protein digestibility-corrected amino acid score (PDCAAS); and the digestible indispensable amino acid score (DIAAS). The possibility that alterations in the quality and quantity of protein in the diet could generate specific health outcomes is one being actively researched. Plant-based proteins may have additional beneficial properties for human health when compared to animal protein sources, including reductions in risk factors for cardiovascular disease and contributions to increased satiety. In this paper, the methods for the determination of protein quality and the potential beneficial qualities of plant proteins to human health will be described.

The Effect of Increasing Concentrations of Omega-3 Fatty Acids from either Flaxseed Oil or Preformed Docosahexaenoic Acid on Fatty Acid Composition, Plasma Oxylipin, and Immune Response of Laying Hens.

BACKGROUND: There is a lack of nutrition guidelines for the feeding of omega-3 polyunsaturated fatty acids (PUFA) to laying hens. Knowledge as to whether the type and concentrations of α-linolenic acid (ALA) and/or docosahexaenoic acid (DHA) in the diet can make a difference to the birds' immune responses when subjected to a lipopolysaccharide (LPS) challenge is limited. OBJECTIVES: The study was designed to determine the potential nutritional and health benefits to laying hens when receiving dietary omega-3 PUFA from either ALA or DHA. METHODS: A total of 80 Lohmann LSL-Classic (white egg layer, 20 wk old) were randomly assigned to 1 of 8 treatment diets (10 hens/treatment), provided 0.2%, 0.4%, 0.6%, or 0.8% of total dietary omega-3 PUFA, provided as either ALA-rich flaxseed oil or DHA-enriched algal biomass. After an 8-wk feeding period, the birds were challenged with Escherichia coli-derived LPS (8 mg/kg; i.v. injection), with terminal sample collection 4 h after challenge. Egg yolk, plasma, liver, and spleen samples were collected for subsequent analyses. RESULTS: Increasing dietary omega-3 supplementation yielded predictable responses in egg yolk, plasma, and liver fatty acid concentrations. Dietary intake of ALA contributed mainly to ALA-derived oxylipins. Meanwhile, eicosapentaenoic acid- and DHA-derived oxylipins were primarily influenced by DHA dietary intake. LPS increased the concentrations of almost all the omega-6 PUFA-, ALA-, and DHA-derived oxylipins in plasma and decreased hepatic mRNA expression of COX-2 and 5-LOX (P < 0.001) involved in the biosynthesis of oxylipins. LPS also increased mRNA expression of proinflammatory cytokine IFN-γ and receptor TLR-4 (P < 0.001) in the spleen. CONCLUSIONS: These results revealed that dietary intake of ALA and DHA had unique impacts on fatty acid deposition and their derived oxylipins and inflammatory responses under the administration of LPS in laying hens.

Quantitative trait loci associated with amino acid concentration and in vitro protein digestibility in pea (Pisum sativum L.).

With the expanding interest in plant-based proteins in the food industry, increasing emphasis is being placed on breeding for protein concentration and quality. Two protein quality traits i.e., amino acid profile and protein digestibility, were assessed in replicated, multi-location field trials from 2019 to 2021 in pea recombinant inbred line population PR-25. This RIL population was targeted specifically for the research of protein related traits and its parents, CDC Amarillo and CDC Limerick, had distinct variations in the concentration of several amino acids. Amino acid profile was determined using near infrared reflectance analysis, and protein digestibility was through an in vitro method. Several essential amino acids were selected for QTL analysis, including lysine, one of the most abundant essential amino acids in pea, and methionine, cysteine, and tryptophan, the limiting amino acids in pea. Based on phenotypic data of amino acid profiles and in vitro protein digestibility of PR-25 harvested in seven location-years, three QTLs were associated with methionine + cysteine concentration, among which, one was located on chromosome 2 (R2 = 17%, indicates this QTL explained 17% phenotypic variation of methionine + cysteine concentration within PR-25), and two were located on chromosome 5 (R2 = 11% and 16%). Four QTLs were associated with tryptophan concentration and are located on chromosome 1 (R2 = 9%), chromosome 3 (R2 = 9%), and chromosome 5 (R2 = 8% and 13%). Three QTLs were associated with lysine concentration, among which, one was located on chromosome 3 (R2 = 10%), the other two were located on chromosome 4 (R2 = 15% and 21%). Two QTLs were associated with in vitro protein digestibility, one each located on chromosomes 1 (R2 = 11%) and 2 (R2 = 10%). QTLs associated with in vitro protein digestibility, and methionine + cysteine concentration on chromosome 2 were identified to be co-localized with known QTL for total seed protein concentration in PR-25. QTLs associated with tryptophan and methionine + cysteine concentration co-localized on chromosome 5. The identification of QTLs associated with pea seed quality is an important step towards marker-assisted selection of breeding lines with improved nutritional quality, which will further boost the competitiveness of pea in plant-based protein markets.

Methionine and cysteine oxidation are regulated in a dose dependent manner by dietary Cys intake in neonatal piglets receiving enteral nutrition.

Methionine (Met) is an indispensable amino acid (AA) in piglets. Met can synthesize cysteine (Cys), and Cys has the ability to reduce the Met requirement by 40% in piglets. However, whether this sparing effect on Met is facilitated by downregulation of Cys synthesis has not been shown. This study investigated the effects of graded levels of Cys on Met and Cys oxidation, and on plasma AA concentrations. Piglets (n = 32) received a complete elemental diet via gastric catheters prior to being randomly assigned to one of the eight dietary Cys levels (0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.40, 0.50 g kg-1d-1) with an adequate Met concentration (0.25g kg-1d-1). Constant infusion of L-[1-14C]-Met and L-[1-14C]-Cys were performed for 6 h on d 6 and d 8 to determine Met and Cys oxidation, respectively. Met oxidation decreased as Cys intake increased (P<0.05). At higher Cys intakes (0.15 to 0.5g kg-1d-1), Met oxidation decreased (P<0.05) at a slower rate. Cys oxidation was similar (P>0.05) among dietary Cys intakes; however, a significant polynomial relationship was observed between Cys oxidation and intake (P<0.05, R2 = 0.12). Plasma Met concentrations increased (P<0.05) linearly with increasing levels of dietary Cys, while plasma Cys concentrations changed (P<0.05) in a cubic manner and the highest concentrations occurred at the highest intake levels. Increasing dietary levels of Cys resulted in a reduction in Met oxidation until the requirement for the total sulfur AA was met, indicating the sparing capacity by Cys of Met occurs through inhibition of the transsulfuration pathway in neonatal piglets.

Guidance and perspectives on highly processed foods.

Guidance from Health Canada to limit highly processed foods (HPF) seeks to ensure that Canadians remain within intake recommendations for nutrients of concern. However, HPF can contribute to dietary requirements of specific populations. The Canadian Nutrition Society and Institute for the Advancement of Food and Nutritional Sciences convened speakers for a Food for Health workshop in 2021 to provide evidence and perspectives from government, industry, and healthcare on reasons for advocating limits and potential unintended consequences of limiting HPF, and implications and necessity of HPF in clinical settings. This paper discusses advantages and disadvantages of HPF explored at this workshop.

Impact of Ultra-High Pressure Homogenization on the Structural Properties of Egg Yolk Granule.

Ultra-high pressure homogenization (UHPH) is a promising method for destabilizing and potentially improving the techno-functionality of the egg yolk granule. This study's objectives were to determine the impact of pressure level (50, 175 and 300 MPa) and number of passes (1 and 4) on the physico-chemical and structural properties of egg yolk granule and its subsequent fractions. UHPH induced restructuration of the granule through the formation of a large protein network, without impacting the proximate composition and protein profile in a single pass of up to 300 MPa. In addition, UHPH reduced the particle size distribution up to 175 MPa, to eventually form larger particles through enhanced protein-protein interactions at 300 MPa. Phosvitin, apovitellenin and apolipoprotein-B were specifically involved in these interactions. Overall, egg yolk granule remains highly stable during UHPH treatment. However, more investigations are needed to characterize the resulting protein network and to evaluate the techno-functional properties of UHPH-treated granule.

Alteration of the dietary methionine: Cysteine ratio modulates the inflammatory response to an inter-peritoneal injection of lipopolysaccharide in wistar rats.

Sulphur amino acids (SAA) are essential for multiple physiological/metabolic processes, with the ratio of dietary methionine: cysteine (Met:Cys) being an important contributor to pro-inflammatory responses, including TNF-α activity. The current study was designed to determine the effect an altered dietary SAA ratio, and the resulting reliance on the transsulfuration pathway to supply Cys, will have on the inflammatory response. In the present study, 100 µg/kg of an intraperitoneal (IP) injection of lipopolysaccharide (LPS) was used as a model for systemic inflammation. Male Wistar rats were randomized to one of two amino acid-defined diets, (100Met:0Cys or 50Met:50Cys) and subdivided to receive either IP LPS or saline injections. LPS significantly increased total plasma Cys, homocysteine (Hcy) and glutathione (GSH) 240 min post-IP injection in rats fed a 50Met:50Cys ratio compared to other treatments. The TNF-α area under the curve for LPS-treated rats consuming a dietary 50Met:50Cys ratio was significantly higher (P < .004) compared to those consuming a dietary 100Met:0Cys ratio. A significant increase in the percentage of leukocytes that were neutrophils was observed in rats injected with LPS when compared to saline with no effect of diet. These results demonstrate that an alteration of the dietary Met:Cys ratio did not attenuate the inflammatory response to an IP injection of LPS in Wistar rats; however, a diet with a balanced Met:Cys ratio increased concentrations of Cys and GSH which may result in a more rapid response to an LPS challenge.

The effect of short-term storage temperature on the key headspace volatile compounds observed in Canadian faba bean flour.

The odour emitted from the high-tannin fab bean flour (Vicia faba var. minor), was characterized by headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS). The relative odour activity value (ROAV) was used to monitor the changes in key volatile compounds in the flour during short-term storage at different temperature conditions. The key flavour compounds of freshly milled flour included hexanal, octanal, nonanal, decanal, 3-methylbutanal, phenyl acetaldehyde, (E)-2-nonenal, 1-hexanol, phenyl ethyl alcohol, 1-octen-3-ol, ß-linalool, acetic acid, octanoic acid, and 3-methylbutyric acid; these are oxidative degradation products of unsaturated fatty acids and amino acids. Despite the low lipid content of faba beans, the abundances of aldehydes arising during room temperature storage greatly contributed to the flavour of the flour due to their very low odour thresholds. Two of the key volatiles responsible for beany flavour in flour (hexanal, nonanal) increased greatly after 2 weeks of storage at room temperature or under refrigerated conditions. These volatile oxidation products may arise as a result of enzymatic activity on unsaturated fatty acids, and was seen to be arrested by freezing the flour.

Genosets for APOE and CYP7A1-rs3808607 variants do not predict LDL cholesterol lowering upon intervention with plant sterols in a randomized, double-blind, placebo-controlled trial.

BACKGROUND: The consumption of 2 g/d plant sterols (PSs) reduces circulating LDL cholesterol by ≤10%. The degree of LDL cholesterol lowering was associated with specific apolipoprotein E [APOE, Reference SNP (rs)429358] and cholesterol 7α-hydroxylase (CYP7A1, rs3808607) genosets in previous post hoc analyses of randomized controlled trials. However, because post hoc analyses do not conform to the randomization model, there is a greater potential that the findings could be due to type I error, thus warranting validation through an a priori-designed intervention trial. OBJECTIVES: The GenePredict Plant Sterol study (GPS) was designed to validate associations of LDL cholesterol lowering with specific APOE and CYP7A1 genosets through a priori recruitment of individuals carrying prespecified genosets. METHODS: A 2-center, double-blind, placebo-controlled, randomized 2-period crossover dietary intervention with 2 g/d PS for 28 d with a minimum 28-d washout was undertaken from July 2017 to December 2019. A priori recruitment of individuals with slightly elevated LDL cholesterol was based on genosets of APOE isoforms and CYP7A1 rs3808607. Randomization was performed with stratification by sex and genoset. RESULTS: The recruitment target of 64 participants with prespecified genosets could not be reached, despite the screening of 477 individuals; 42 participants completed the intervention trial. Reductions in LDL cholesterol were similar across all 3 genosets (-0.298 ± 0.164, -0.357 ± 0.115, -0.293 ± 0.109 mmol/L; P = 0.0002 overall; P = 0.9126 for treatment × genoset), providing evidence that the shortfall in recruitment might not have stopped the trial from meeting the objective. CONCLUSIONS: APOE and CYP7A1 genotypes did not influence the efficacy of LDL cholesterol reductions upon dietary intervention with PSs. Findings of previous post hoc analyses could not be validated in a trial using a priori genotype-based recruitment. Obtaining adequate numbers of participants is challenging in trials using genoset-based recruitment, even for common variants.

Effect of roasting pulse seeds at different tempering moisture on the flour functional properties and nutritional quality.

Knowledge on the functional and nutritional properties of wet roasted pulses can increase the utilization of processed pulses as ingredients in food products. This study investigated the effects of tempering different pulse [chickpea (CP), green lentil (GL), navy bean (NB) and yellow pea (YP)] seeds to 20 or 30% moisture prior to roasting (160℃ for 30 min) on the functional properties and nutritional quality of their resulting flours. The surface charge of each pulse remained the same (p > 0.05) after wet roasting and there were no significant (p > 0.05) differences between the different raw pulse flours. The oil holding capacity (OHC) of GL (~2 g/g) was not improved by wet roasting (p > 0.05) whereas the other pulses generally had better OHC for one or both of the tempering moistures used prior to roasting. Foaming properties of all pulses decreased after heat treatment with the exception of both foaming capacity (107%) and stability (~71%) for GL tempered to 20% moisture prior to roasting (p > 0.05). Raw GL had inferior foaming properties compared to the other raw pulse flours (p < 0.001). Emulsion properties of the wet roasted pulses were similar to those of the control (raw flour) for each pulse. Solubility decreased with roasting regardless of the tempering moisture (p < 0.05) whereas in general the in vitro protein digestibility increased. Small improvements (2.4-6.9% increase) in the in vitro protein digestibility-corrected amino acid score were found for GL and NB tempered to 20% moisture before roasting and roasted YP at either moisture content (p < 0.05). Wet roasting increased (p < 0.05) the rapidly digestible starch content, more so with a tempering moisture of 30%. Overall the results from this study will allow for the utilization of wet roasted pulses as ingredients based on their functional properties and protein quality.

Sprouting improves the flavour quality of faba bean flours.

Flours were made from the sprouted seeds of the low- and high-tannin faba bean cultivars Fabelle, FB9-4, Snowbird, and Snowdrop. Headspace measurements on sprouted flours found the most favourable aroma profiles following 48 h sprouting and 24 h drying at 60 °C. Lipoxygenase activity, and the tannin, protein, and moisture contents were determined for unsprouted and sprouted faba bean flours. Lipoxygenase activity was higher in sprouted seeds before drying. Protein content increased after sprouting, whereas the tannin content decreased, especially for high-tannin varieties. Key volatile flavour compounds of faba bean flours included pentanal, hexanal, heptanal, octanal, nonanal, decanal, 1-hexanol, 1-octen-3-ol, 3-methylbutanal, phenyl acetaldehyde, 3-methylbutyric acid, d-limonene, ß-linalool, menthol, and estragole; these include oxidative degradation products of oleic, linoleic, and some amino acids. An overall flavour improvement was achieved after germination, as indicated by a decrease in bitter compounds (tannins) and beany flavours (hexanal, nonanal, 2-heptanone, and 2-pentylfuran).

A combination of single nucleotide polymorphisms is associated with the interindividual variability in the blood lipid response to dietary fatty acid consumption in a randomized clinical trial.

BACKGROUND: Blood lipid concentrations display high interindividual variability in response to dietary interventions, partly due to genetic factors. Existing studies have focused on single nucleotide polymorphisms (SNPs) analyzed individually, which only explain a limited fraction of the variability of these complex phenotypes. OBJECTIVE: We aimed to identify combinations of SNPs associated with the variability in LDL cholesterol and triglyceride (TG) concentration changes following 5 dietary interventions. DESIGN: In a multicenter randomized crossover trial, 92 participants with elevated waist circumference and low HDL cholesterol concentrations consumed 5 isoenergetic diets for 4 wk: a diet rich in saturated fatty acids (SFAs) from cheese, SFA from butter, monounsaturated fatty acids (MUFAs), n-6 polyunsaturated fatty acids (PUFAs), and a diet higher in carbohydrates (CHO). The association between 22 candidate SNPs in genes involved in lipid and bile acid metabolism and transport and changes in LDL cholesterol and TG concentrations was assessed with univariate statistics followed by partial least squares regression. RESULTS: Endpoint LDL cholesterol concentrations were significantly different (cheese: 3.18 ± 0.04, butter: 3.31 ± 0.04, MUFA: 3.00 ± 0.04, PUFA: 2.81 ± 0.04, CHO: 3.11 ± 0.04 mmol/L; P < 0.001) while endpoint TG concentrations were not (P = 0.117). Both displayed consistently elevated interindividual variability following the dietary interventions (CVs of 34.5 ± 2.2% and 55.8 ± 1.8%, respectively). Among the 22 candidate SNPs, only ABCA1-rs2066714 and apolipoprotein E (APOE) isoforms exhibited consistent significant effects, namely on LDL cholesterol concentrations. However, several SNPs were significantly associated with changes in LDL cholesterol and TG concentrations in a diet-specific fashion. Generated multivariate models explained from 16.0 to 33.6% of the interindividual variability in LDL cholesterol concentration changes and from 17.5 to 32.0% of that in TG concentration changes. CONCLUSIONS: We report combinations of SNPs associated with a significant part of the variability in LDL cholesterol and TG concentrations following dietary interventions differing in their fatty acid profiles.

Common Genetic Variations Involved in the Inter-Individual Variability of Circulating Cholesterol Concentrations in Response to Diets: A Narrative Review of Recent Evidence.

The number of nutrigenetic studies dedicated to the identification of single nucleotide polymorphisms (SNPs) modulating blood lipid profiles in response to dietary interventions has increased considerably over the last decade. However, the robustness of the evidence-based science supporting the area remains to be evaluated. The objective of this review was to present recent findings concerning the effects of interactions between SNPs in genes involved in cholesterol metabolism and transport, and dietary intakes or interventions on circulating cholesterol concentrations, which are causally involved in cardiovascular diseases and established biomarkers of cardiovascular health. We identified recent studies (2014-2020) that reported significant SNP-diet interactions in 14 cholesterol-related genes (NPC1L1, ABCA1, ABCG5, ABCG8, APOA1, APOA2, APOA5, APOB, APOE, CETP, CYP7A1, DHCR7, LPL, and LIPC), and which replicated associations observed in previous studies. Some studies have also shown that combinations of SNPs could explain a higher proportion of variability in response to dietary interventions. Although some findings still need replication, including in larger and more diverse study populations, there is good evidence that some SNPs are consistently associated with differing circulating cholesterol concentrations in response to dietary interventions. These results could help clinicians provide patients with more personalized dietary recommendations, in order to lower their risk for cardiovascular disease.

The effect of increasing intakes of plant protein on the protein quality of Canadian diets.

The 2015 Canadian Community Health Survey was used to investigate the protein content and protein quality of the diets consumed by adults (≥19 years) when plant protein is increased. Individuals (n = 6498) were allocated to quartiles of increasing proportions of protein from plant foods (Quartile 1: 0-24.9%; Quartile 2: 25%-49.9%; Quartile 3: 50-74.9%; Quartile 4: 75-100%). The Protein Digestibility Corrected Amino Acid Score (PDCAAS) of diets were estimated using indispensable amino acid concentrations of foods and an assumed digestibility coefficient of 0.8. Corrected protein intakes were determined by aggregating foods consumed over 24 hours and as the sum of corrected protein consumed at eating events within six 4-hour time intervals. Most individuals (51%) consumed 25-49.9% of protein from plant foods. Cereal-based foods represented the majority of plant protein consumed. PDCAAS of diets remained ≥0.87 for quartiles 1-3, but decreased (p < 0.0001) to 0.71 ± 0.018 in quartile 4 vs. quartile 2 (0.96 ± 0.004). Corrected protein intakes in quartile 2 (80.66 ± 1.21 g/day; 1.07 ± 0.03 g protein/kg body weight) decreased to 37.13 ± 1.88 g/day (0.54 ± 0.03 g/kg body weight) in quartile 4 (p < 0.0001). Aggregated daily corrected protein intake strongly correlated (r = 0.99; p < 0.001) with the sum of corrected protein consumed within time intervals. Intra-time interval analysis revealed that the relative proportions of animal and plant proteins changed at eating events over 24 hours and did not reflect the allocation to quartiles based on the daily proportion of plant protein consumption. Various tools should be explored and developed to assist Canadians in effectively incorporating plant protein foods into dietary patterns. Novelty: Corrected protein intakes decreased as plant protein consumption increased. PDCAAS was ≥0.87 for diets with ≤74.9% plant protein.