Acetylcholinesterase and butyrylcholinesterase inhibitory activities of antioxidant peptides obtained from enzymatic pea protein hydrolysates and their ultrafiltration peptide fractions.

This study optimized the enzymatic hydrolysis of yellow field pea proteins using alcalase (ACH), chymotrypsin (CHH), flavourzyme (FZH), pancreatin (PCH), pepsin (PEH), and trypsin (TPH) to obtain hydrolysates and ultrafiltered fractions (<1, 1-3, 3-5 and 5-10 kDa) that possess antioxidant plus acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities. The hydrolysates exhibited varying degrees of radical scavenging and inhibition of linoleic acid peroxidation, as well as cholinesterase inhibition activities but the potency generally improved by >10% after UF separation into peptide fractions. ACH, FZH, and PEH exhibited significantly (p < .05) higher (20%-30% increases) radical scavenging activities than the other hydrolysates. The 1 and 3 kDa UF fractions of ACH, FZH, and PEH inhibited ~20%-30% AChE activity, while ACH, PCH, TPH, and PEH inhibited ~20%-40% BuChE activity. We conclude that the pea protein hydrolysates and their peptide fractions possess multifunctional properties with potential use against neurodegenerative disorders. PRACTICAL APPLICATIONS: Alzheimer's disease (AD) has multiple pathological pathways in addition to the loss of acetylcholine (ACh) catalyzed by acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The presence of severe oxidative stress triggered by lipid peroxidation and formation of free radicals is a common trait in AD patients. The concept of AChE and BuChE inhibition as an approach toward AD amelioration involves the use of compounds with a similar structure to ACh, the natural substrate. Peptides derived from food proteins consist of ester bonds with structural similarity to ACh and theoretically possess the ability to interact with AChE and BuChE. Results from the present study imply that pea protein-derived peptides are potential candidates for use as inhibitors of AChE and BuChE activities, with application in the prevention and management of AD.

Pea Proteins Have Anabolic Effects Comparable to Milk Proteins on Whole Body Protein Retention and Muscle Protein Metabolism in Old Rats.

Plant proteins are attracting rising interest due to their pro-health benefits and environmental sustainability. However, little is known about the nutritional value of pea proteins when consumed by older people. Herein, we evaluated the digestibility and nutritional efficiency of pea proteins compared to casein and whey proteins in old rats. Thirty 20-month-old male Wistar rats were assigned to an isoproteic and isocaloric diet containing either casein (CAS), soluble milk protein (WHEY) or Pisane™ pea protein isolate for 16 weeks. The three proteins had a similar effect on nitrogen balance, true digestibility and net protein utilization in old rats, which means that different protein sources did not alter body composition, tissue weight, skeletal muscle protein synthesis or degradation. Muscle mitochondrial activity, inflammation status and insulin resistance were similar between the three groups. In conclusion, old rats used pea protein with the same efficiency as casein or whey proteins, due to its high digestibility and amino acid composition. Using these plant-based proteins could help older people diversify their protein sources and more easily achieve nutritional intake recommendations.

The Impact of Low-Level Iron Supplements on the Faecal Microbiota of Irritable Bowel Syndrome and Healthy Donors Using In Vitro Batch Cultures.

Ferrous iron supplementation has been reported to adversely alter the gut microbiota in infants. To date, the impact of iron on the adult microbiota is limited, particularly at low supplementary concentrations. The aim of this research was to explore the impact of low-level iron supplementation on the gut microbiota of healthy and Irritable Bowel Syndrome (IBS) volunteers. Anaerobic, pH-controlled in vitro batch cultures were inoculated with faeces from healthy or IBS donors along with iron (ferrous sulphate, nanoparticulate iron and pea ferritin (50 µmol-1 iron)). The microbiota were explored by fluorescence in situ hybridisation coupled with flow cytometry. Furthermore, metabolite production was assessed by gas chromatography. IBS volunteers had different starting microbial profiles to healthy controls. The sources of iron did not negatively impact the microbial population, with results of pea ferritin supplementation being similar to nanoparticulate iron, whilst ferrous sulphate led to enhanced Bacteroides spp. The metabolite data suggested no shift to potentially negative proteolysis. The results indicate that low doses of iron from the three sources were not detrimental to the gut microbiota. This is the first time that pea ferritin fermentation has been tested and indicates that low dose supplementation of iron is unlikely to be detrimental to the gut microbiota.

Evaluation of a Product Containing Xyloglucan and Pea Protein on Skin Barrier Permeability.

OBJECTIVE: The skin acts as a mechanical and protective barrier against viral, fungal, and bacterial infections. Skin conditions such as atopic dermatitis and psoriasis are characterized by alterations of the skin barrier, often caused by injury and by bacterial infections. In the last years, non-pharmacological interventions have gained great importance in epidermis-related diseases. Xyloglucan (XG) is a polysaccharide that possesses a "mucin-like" molecular structure that confers mucoadhesive properties, allowing XG-containing formulations to act as a protective barrier for the management of different diseases. Moreover, there is also increasing interest in the use of proteins due to their film-forming features. This study aimed to evaluate the barrier-protective properties of a product containing XG and pea protein (PP) in an in vitro model, assessing its effects on the membrane permeability of keratinocytes infected by Staphylococcus aureus. METHODS: HaCaT keratinocytes were pretreated with XG and PP for 3 h and then infected with S. aureus cells (106 bacteria/well) at a multiplicity of infection of 10 for 1 h. The number of bacterial colonies and membrane integrity were measured, respectively. RESULTS: We observed that pretreatment with XG and PP in human HaCaT keratinocytes infected with S. aureus significantly increased trans-epithelial electrical resistance (a marker of skin barrier function) measurement, reduced lucifer yellow (a marker of membrane integrity) permeation across the monolayer, and released lactate dehydrogenase (a marker of tissue damage). Moreover, XG and PP pretreatment was able to reduce bacterial adherence, avoiding S. aureus infection. CONCLUSION: In summary, we demonstrated that the product containing XG and PP was able to maintain barrier permeability preserving its integrity, and therefore, it can be considered as an interesting approach for the management of epidermis-related diseases.

Effects of Whey and Pea Protein Supplementation on Post-Eccentric Exercise Muscle Damage: A Randomized Trial.

This randomized trial compared pea protein, whey protein, and water-only supplementation on muscle damage, inflammation, delayed onset of muscle soreness (DOMS), and physical fitness test performance during a 5-day period after a 90-min eccentric exercise bout in non-athletic non-obese males (n = 92, ages 18-55 years). The two protein sources (0.9 g protein/kg divided into three doses/day) were administered under double blind procedures. The eccentric exercise protocol induced significant muscle damage and soreness, and reduced bench press and 30-s Wingate performance. Whey protein supplementation significantly attenuated post-exercise blood levels for biomarkers of muscle damage compared to water-only, with large effect sizes for creatine kinase and myoglobin during the fourth and fifth days of recovery (Cohen's d > 0.80); pea protein versus water supplementation had an intermediate non-significant effect (Cohen's d < 0.50); and no significant differences between whey and pea protein were found. Whey and pea protein compared to water supplementation had no significant effects on post-exercise DOMS and the fitness tests. In conclusion, high intake of whey protein for 5 days after intensive eccentric exercise mitigated the efflux of muscle damage biomarkers, with the intake of pea protein having an intermediate effect.

Effect of a Product Containing Xyloglucan and Pea Protein on a Murine Model of Atopic Dermatitis.

Atopic dermatitis (AD) is a chronic inflammatory disease of the skin, characterized by dryness and more or less severe itching. The etiology of AD is complex and has not been fully clarified, involving genetic susceptibility, immunological abnormalities, epidermal barrier dysfunction, and environmental factors. Xyloglucan (XG) and pea protein (PP) are two compounds of natural origin characterized by the ability to create a physical barrier that protects mucosae membranes, reducing inflammation. The aim of the present study was to evaluate the potential beneficial effects of XG + PP in both a mouse model of AD and Staphylococcus aureus (S.aureus) infection- associated AD. Mice were topically treated with 200 µL of 0.5% oxazolone on the dorsal skin three times a week for AD induction. Mice received XG and PP by topical administration 1 h before oxazolone treatment. In S. aureus infection-associated AD, to induce a superficial superinfection of the skin, mice were also treated with 5 µL of 108 of a culture of S. aureus for 2 weeks; mice superinfected received XG and PP by topical administration 1 h before oxazolone + S. aureus. Four weeks later, the skin was removed for histological and biochemical analysis. Our results demonstrated the protective barrier effects of XG and PP characterized by a reduction in histological tissue changes, mastocyte degranulation, and tight junction permeability in the skin following oxazolone treatment. Moreover, XG + PP was able to preserve filaggrin expression, a hallmark of AD. Our data also support the effectiveness of XG + PP to reduce the damage by superinfection post AD induced by S. aureus. In conclusion, a future product containing XG and PP could be considered as a potentially interesting approach for the treatment of AD.