Hydrophobicity of whey protein hydrolysates enhances the protective effect against oxidative damage on PC 12 cells

Digestion of whey peptide induces antioxidant and anti-inflammatory bioactivity on glial cells: Sequences identification and structural activity analysis

Whey derived peptides have shown potential activity improving brain function in pathological condition. However, there is little information about their mechanism of action on glial cells, which have important immune functions in brain. Astrocytes and microglia are essential in inflammatory and oxidative defense that take place in neurodegenerative disease. In this work we evaluate antioxidant and anti-inflammatory potential bioactivity of whey peptide in glial cells. Peptides were formed during simulated gastrointestinal digestion (Infogest protocol), and low molecular weight (<5kDA) peptides (WPHf) attenuated reactive oxygen species (ROS) production induced by hydrogen peroxide stimulus in both cells in dose-dependent manner. WPHf induced an increase in the antioxidant glutathione (GSH) content and prevented GSH reduction induced by lipopolysaccharides (LPS) stimulus in astrocytes cells in a cell specific form. An increase in cytokine mRNA expression (TNFα and IL6) and nitric oxide secretion induced by LPS was attenuated by WPHf pre-treatment in both cells. The inflammatory pathway was dependent on NFκB activation. Bioactive peptide ranking analysis showed positive correlation with hydrophobicity and negative correlation with high molecular weights. The sequence identification revealed 19 peptides cross-referred with bioactive database. Whey peptides were rich in leucine, valine and tyrosine in the C-terminal region and lysine in the N-terminal region. The anti-inflammatory and antioxidant potential of whey peptides were assessed in glia cells and its mechanisms of action were related, such as modulation of antioxidant enzymes and anti-inflammatory pathways. Features of the peptide structure, such as molecular size, hydrophobicity and types of amino acids present in the terminal region are associated to bioactivity.

Food-derived Peptides as Promising Neuroprotective Agents: Mechanism and Therapeutic Potential

Many food-derived peptides have the potential to improve brain health and slow down neurodegeneration. Peptides are produced by the enzymatic hydrolysis of proteins from different food sources. These peptides have been shown to be involved in antioxidant and anti-inflammatory activity, neuro-transmission modulation, and gene expression regulation. Although few peptides directly affect chromatin remodeling and histone alterations, others indirectly affect the neuroprotection process by interfering with epigenetic changes. Fish-derived peptides have shown neuroprotective properties that reduce oxidative stress and improve motor dysfunction in Parkinson's disease models. Peptides from milk and eggs have been found to have anti-inflammatory properties that reduce inflammation and improve cognitive function in Alzheimer's disease models. These peptides are potential therapeutics for neurodegenerative diseases, but more study is required to assess their efficacy and the underlying neuroprotective benefits. Consequently, this review concentrated on each mechanism of action used by food-derived peptides that have neuroprotective advantages and applications in treating neurodegenerative diseases. This article highlights various pathways, such as inflammatory pathways, major oxidant pathways, apoptotic pathways, neurotransmitter modulation, and gene regulation through which food-derived peptides interact at the cellular level.

In Vitro Anti-Obesity Effect of Shenheling Extract (SHLE) Fermented with Lactobacillus fermentum grx08

Obesity is a common global problem. There are many fat-reducing herbal prescriptions in traditional Chinese medicine that have been proven to be safe and functional during long-term application. Microbial fermentation can improve the efficacy of herbal medicine and improve the unsavory flavor. In this study, Shenheling extract (SHLE) composed of six medicine food homology materials was used as the research object. The purpose of this study was to evaluate the effects of Lactobacillusfermentum grx08 fermentation on the antiobesity efficacy and flavor of SHLE. We found that L. fermentum grx08 grew well in SHLE. After 72 h of fermentation, the total polysaccharides, total flavonoids, total polyphenols and total saponins of SHLE decreased, but the lipase inhibitory activity and total antioxidant capacity (FRAP) were significantly increased (p < 0.01). There were no significant differences in the α-glucosidase inhibition rate and DPPH· clearance rate before or after fermentation (p > 0.05). In addition, the fermentation reduces the unpleasant flavors of SHLE such as bitterness and grassy and cassia flavors. This study demonstrates that SHLE fermented by L. fermentum grx08 improved some anti-obesity functions and improved the unpleasant flavor.

Hydrolase-Treated Royal Jelly Attenuates H2O2- and Glutamate-Induced SH-SY5Y Cell Damage and Promotes Cognitive Enhancement in a Rat Model of Vascular Dementia

Vascular dementia (VaD) is the second most common type of dementia following Alzheimer's disease, but the therapeutic efficacy is still not effective. This makes the searching for novel neuroprotective agents important. Therefore, we hypothesized that royal jelly, a well-known traditional medicine, could attenuate memory impairment and brain damage in vascular dementia. This study determined the effects of royal jelly hydrolysate (RJH) and possible mechanism of cell damage and cognitive-enhancing effect in animal study. An in vitro study assessed the effects of RJH on acetylcholinesterase inhibitor, cell viability, and cell damage in SH-SY5Y neuroblastoma cells. Then, an in vivo study examined vascular dementia by the occlusion of the right middle cerebral artery (Rt.MCAO); adult male Wistar rats had been orally given RJH at doses ranging from 10, 50, to 100 mg/kg for 14 days before and 14 days after the occlusion of Rt.MCAO to mimic the VaD condition. Rats' spatial memory was evaluated using Morris water maze and radial arm maze every 7 days after Rt.MCAO throughout a 14-day experimental period, and then, they were sacrificed and the acetylcholinesterase (AChE) activity in the hippocampus was determined. The results showed that RJH has no cytotoxic effect with the final concentration up to 500 μg protein/ml and reduces cell death from the H₂O₂- and glutamate-induced cell damage in in vitro neuroblastoma cells. Importantly, RJH significantly improved memory performance in Morris water maze test and radial arm maze and decreased the level of acetyl cholinesterase activity. In conclusion, RJH is the potential neuroprotective agent and cognitive enhancer for VaD.

Advances on Food-Derived Peptidic Antioxidants-A Review

The oxidation process is considered to be the main reason behind human aging, human degenerative diseases and food quality degradation. Food-derived peptidic antioxidants (PAs) have wide sources and great activity, and have broad application prospects in removing excess reactive oxygen species in the body, anti-aging and preventing and treating diseases related to oxidative stress. On the other hand, PAs are expected to inhibit the lipid peroxidation of foods and increase the stability of the food system in the food industry. However, the production pathways and action mechanism of food-derived PAs are diverse, which makes it is difficult to evaluate the performance of PAs which is why the commercial application of PAs is still in its infancy. This article focuses on reviewing the preparation, purification, and characterization methods of food-derived PAs, and expounds the latest progress in performance evaluation and potential applications, in order to provide an effective reference for subsequent related research of PAs.

Synthesis and evaluation of isoprenylation-resveratrol dimer derivatives against Alzheimer's disease

A series of resveratrol dimer derivatives against Alzheimer's disease (AD) was obtained by structural modification and transformation using resveratrol as substrate. Biological analysis revealed that these derivatives had moderate inhibitory activity against human monoamine oxidase B (hMAO-B). In particular, 3 and 7 showed the better inhibitory activity for hMAO-B (IC50 = 3.91 ± 0.23 μM, 0.90 ± 0.01 μM) respectively. Compound 3 (IC50 = 46.95 ± 0.21 μM for DPPH, 1.43 and 1.74 trolox equivalent by ABTS and FRAP method respectively), and 7 (IC50 = 35.33 ± 0.15 μM for DPPH, 1.70 and 1.97 trolox equivalent by ABTS method and FRAP method respectively) have excellent antioxidant effects. Cellular assay shown that 3 and 7 had lower toxicity and were resistant to neurotoxicity induced by oxidative toxins (H2O2, rotenone and oligomycin-A). More importantly, the selected compounds have neuroprotective effects against ROS generation, H2O2-induced apoptosis and a significant in vitro anti-inflammatory activity. The results of the parallel artificial membrane permeability assay for blood-brain barrier indicated that 3 and 7 would be predominant to cross the blood-brain barrier. In this study, mouse microglia BV2 cells were used to establish cell oxidative stress injury model with H2O2 and to explore the protective effect and mechanism of 3 and 7. In general, 3 and 7 can be considered candidates for potential treatment of AD.

Acetoacetic acid induces oxidative stress to inhibit the assembly of very low density lipoprotein in bovine hepatocytes

Dairy cows with fatty liver or ketosis exhibit hyperketonemia, oxidative stress, and a low rate of very low density lipoprotein (VLDL) assembly, and there may be a potential link among these characteristics. Therefore, the objective of this study was to determine the effect of acetoacetic acid (AcAc) on the assembly of VLDL in cow hepatocytes. Cultured cow hepatocytes were treated with different concentrations of AcAc with or without N-acetylcysteine (NAC, an antioxidant). AcAc treatment decreased the mRNA expression and activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and significantly increased malondialdehyde (MDA) content, indicative of oxidative stress. Furthermore, AcAc treatment significantly down-regulated the mRNA expression of apolipoprotein B100 (ApoB100), apolipoprotein E (ApoE), and low density lipoprotein receptor (LDLR), which thus decreased VLDL assembly and increased triglyceride (TG) accumulation in these bovine hepatocytes. Importantly, NAC relieved AcAc-induced oxidative stress and increased VLDL assembly. In summary, these results suggest that AcAc-induced oxidative stress affects the assembly of VLDL, which increases TG accumulation in bovine hepatocytes.

Dairy cheese consumption ameliorates single-meal sodium-induced cutaneous microvascular dysfunction by reducing ascorbate-sensitive oxidants in healthy older adults

Chronic dairy product intake is associated with improved cardiovascular outcomes, whereas high dietary Na impairs endothelial function through increased oxidative stress and reduced nitric oxide (NO) bioavailability. The purpose of this study was to compare the effect of acute cheese consumption with consumption of Na from non-dairy sources on microvascular function. We hypothesised that dairy cheese ingestion would augment NO-dependent vasodilation compared with Na from non-dairy sources. On five visits, fourteen subjects (61 (sem 2) years, eight male/six female) consumed either 85 g dairy cheese (560 mg Na), 85 g soya cheese (560 mg Na), 65 g pretzels (560 mg Na), 170 g dairy cheese (1120 mg Na) or 130 g pretzels (1120 mg Na). Two intradermal microdialysis fibres were inserted in the ventral forearm for delivery of lactated Ringer's solution or 10 mm-ascorbate (antioxidant) during local skin heating (approximately 50 min). Erythrocyte flux was measured continuously by laser-Doppler flowmetry (LDF), and cutaneous vascular conductance (CVC=LDF/mean arterial pressure) was normalised as %CVCmax (28 mm-sodium nitroprusside). Following a plateau in CVC, 15 mm-N G -nitro-l-arginine-methyl-ester was perfused to quantify NO-dependent vasodilation (approximately 45 min). NO-dependent vasodilation was greater following consumption of dairy products (560 mg Na 57 (sem 3) %) (1120 mg Na 55 (sem 5) %) compared with soya (560 mg Na 42 (sem 3) %; P=0·002) or pretzels (560 mg Na 43 (sem 4) %; P=0·004) (1120 mg Na 46 (sem 3) %; P=0·04). Ascorbate augmented NO-dependent vasodilation following intake of soya (control: 42 (sem 3) v. ascorbate: 54 (sem 3) %; P=0·01) or pretzels (560 mg Na; control: 43 (sem 4) v. ascorbate: 56 (sem 3) %; P=0·006) (1120 mg Na; control: 46 (sem 5) v. ascorbate: 56 (sem 3) %; P=0·02), but not dairy products. Na ingestion via dairy products was associated with greater NO-dependent vasodilation compared with non-dairy products, a difference that was ameliorated with ascorbate perfusion. The antioxidant properties of dairy proteins may protect against Na-induced reductions in NO-dependent dilation.