Chicken Muscle-Derived ACE2 Upregulating Peptide VVHPKESF Inhibits Angiotensin II-Stimulated Inflammation in Vascular Smooth Muscle Cells via the ACE2/Ang (1-7)/MasR Axis

Food-Derived Up-Regulators and Activators of Angiotensin Converting Enzyme 2: A Review

Angiotensin-converting enzyme 2 (ACE2) is a key enzyme in the renin-angiotensin system (RAS), also serving as an amino acid transporter and a receptor for certain coronaviruses. Its primary role is to protect the cardiovascular system via the ACE2/Ang (1-7)/MasR cascade. Given the critical roles of ACE2 in regulating numerous physiological functions, molecules that can upregulate or activate ACE2 show vast therapeutic value. There are only a few ACE2 activators that have been reported, a wide range of molecules, including food-derived compounds, have been reported as ACE2 up-regulators. Effective doses of bioactive peptides range from 10 to 50 mg/kg body weight (BW)/day when orally administered for 1 to 7 weeks. Protein hydrolysates require higher doses at 1000 mg/kg BW/day for 20 days. Phytochemicals and vitamins are effective at doses typically ranging from 10 to 200 mg/kg BW/day for 3 days to 6 months, while Traditional Chinese Medicine requires doses of 1.25 to 12.96 g/kg BW/day for 4 to 8 weeks. ACE2 activation is linked to its hinge-bending region, while upregulation involves various signaling pathways, transcription factors, and epigenetic modulators. Future studies are expected to explore novel roles of ACE2 activators or up-regulators in disease treatments and translate the discovery to bedside applications.

Chicken Muscle-Derived ACE2-Upregulating Peptide VVHPKESF Reduces Blood Pressure Associated with the ACE2/Ang (1-7)/MasR Axis in Spontaneously Hypertensive Rats

SCOPE

This study aims to investigate the antihypertensive effect of four chicken muscle-derived angiotensin (Ang)-converting enzymes (ACE)-regulating peptides: Val-Arg-Pro (VRP, ACE inhibition), Leu-Lys-Tyr and Val-Arg-Tyr (LKY and VRY, ACE inhibition and ACE2 upregulation), and Val-Val-His-Pro-Lys-Glu-Ser-Phe (VVHPKESF [V-F], ACE2 upregulation) in spontaneously hypertensive rats.

METHODS AND RESULTS

Rats (12-14 weeks old) are grouped: 1) untreated, 2) VRP, 3) LKY, 4) VRY, and 5) V-F. Blood pressure (BP) is monitored using implantable telemetry technology. Over 18-day oral administration of 15 mg kg-1 body weight (BW) per day, only peptide V-F significantly (p < 0.05) reduces BP, decreases circulating Ang II, and increases ACE2 and Ang (1-7) levels, and enhances aortic expressions of ACE2 and Mas receptor (MasR). Peptide V-F also attenuates vascular inflammation (TNFα, MCP-1, IL-1α, IL-15, and cyclooxygenase 2 [COX2]) and vascular oxidative stress (nitrotyrosine). The gastrointestinal (GI)-degraded fragment of peptide V-F, Val-Val-His-Pro-Lys (VVHPK), is also an ACE2-upregulating peptide. Peptides VRP, LKY, and VRY do not reduce BP, possibly due to low bioavailability or other unknown reasons.

CONCLUSIONS

Peptide V-F is the first ACE2-upregulating peptide, purified and fractionated from food proteins based on in vitro ACE2 upregulation, that reduces BP associated with the activation of ACE2/Ang (1-7)/MasR axis; the N-terminal moiety VVHPK may be responsible for the antihypertensive effect of V-F.

Identification and Screening of Potential ACE2 Activating Peptides from Soybean Protein Isolate Hydrolysate against Ang II-Induced Endothelial Dysfunction

Angiotensin-converting enzyme 2 (ACE2) is a counterregulator against ACE by converting angiotensin II (Ang II) to Ang-(1-7), and its down-regulation leads to endothelial dysfunction in the vascular system. In the present study, we investigated the effects of soybean protein isolate hydrolysate (SPIH) on Ang II-induced endothelial dysfunction with its underlying mechanisms via ACE2 activation in human umbilical vein endothelial cells (HUVECs). We further screened potential ACE2 activating peptides by peptidomics analysis combined with bioinformatics tools. Results showed that SPIH remarkably attenuated Ang II-induced cell migration from 129 to 92%, decreased the ROS level from 2.22-fold to 1.45-fold, and increased NO concentration from 31.4 ± 0.7 to 43.7 ± 0.1 μM in HUVECs. However, these beneficial effects were reversed by ACE2 inhibitor MLN-4760 to a certain extent, indicating the modulation of ACE2. Further results revealed that SPIH (1 mg/mL) significantly increased the expression and activity of ACE2 and two novel ACE2 activating peptides with different mechanisms were explored from SPIH. IVPQ and IAVPT (50 μM) enhanced ACE2 activity, and only IVPQ (50 μM) increased ACE2 protein expression in HUVECs. These findings furthered our understanding of the antihypertensive mechanism of SPIH mediating the ACE2 activation on vascular endothelium.

Peptidomics Study of Plant-Based Meat Analogs as a Source of Bioactive Peptides

The demand for plant-based meat analogs (PBMA) is on the rise as a strategy to sustain the food protein supply while mitigating environmental change. In addition to supplying essential amino acids and energy, food proteins are known sources of bioactive peptides. Whether protein in PBMA affords similar peptide profiles and bioactivities as real meat remains largely unknown. The purpose of this study was to investigate the gastrointestinal digestion fate of beef and PBMA proteins with a special focus on their potential as precursors of bioactive peptides. Results showed that PBMA protein showed inferior digestibility than that in beef. However, PBMA hydrolysates possessed a comparable amino acid profile to that of beef. A total of 37, 2420 and 2021 peptides were identified in the gastrointestinal digests of beef, Beyond Meat and Impossible Meat, respectively. The astonishingly fewer peptides identified from beef digest is probably due to the near-full digestion of beef proteins. Almost all peptides in Impossible Meat digest were from soy, whereas 81%, 14% and 5% of peptides in Beyond Meat digest were derived from pea, rice and mung proteins, respectively. Peptides in PBMA digests were predicted to exert a wide range of regulatory roles and were shown to have ACE inhibitory, antioxidant and anti-inflammatory activities, supporting the potential of PBMA as a source of bioactive peptides.

Soybean-Derived Tripeptide Leu-Ser-Trp (LSW) Protects Human Vascular Endothelial Cells from TNFα-Induced Oxidative Stress and Inflammation via Modulating TNFα Receptors and SIRT1

Soybean is a rich source of high-quality proteins and an excellent food source of bioactive peptides. A tripeptide, Leu−Ser−Trp (LSW), was previously identified from soybean as an angiotensin-converting enzyme inhibitory peptide. In the present work, we further studied its antioxidant and anti-inflammatory activities in human vascular endothelial cells (EA.hy926) and elucidated the mechanisms underlying these biological activities. In tumor necrosis factor alpha (TNFα)-stimulated EA.hy926 cells, LSW significantly inhibited oxidative stress, both reduced superoxide and malondialdehyde levels (p < 0.001), owing to its free-radical-scavenging ability. LSW treatment also mitigated the elevated protein expression of vascular adhesion molecule-1 (p < 0.001) and cyclooxygenase 2 (p < 0.01) via inhibition of NF-κB and p38/JNK signaling, respectively. Additionally, LSW also inhibited the endogenous formation of TNFα and attenuated the expression of its two receptors in EA.hy926 cells. Furthermore, LSW upregulated sirtuin-1 level, which partially contributed to its anti-inflammatory activity. These results demonstrate the multiple roles of LSW in ameliorating vascular endothelial oxidative stress and inflammatory responses, which support its uses as a nutraceutical or functional food ingredient for combating endothelial dysfunction and cardiovascular diseases.

Chicken muscle protein-derived peptide VVHPKESF reduces TNFα-induced inflammation and oxidative stress by suppressing TNFR1 signaling in human vascular endothelial cells

SCOPE

This study aimed to investigate the protective effects of four chicken muscle-derived peptides (Val-Arg-Pro (VRP), Leu-Lys-Tyr (LKY), Val-Arg-Tyr (VRY), and Val-Val-His-Pro-Lys-Glu-Ser-Phe [VVHPKESF (V-F)] on tumor necrosis factor alpha (TNFα)-induced endothelial inflammation and oxidative stress in human vascular endothelial EA.hy926 cells.

METHODS AND RESULTS

Inflammation and oxidative stress are induced in EA.hy926 cells by TNFα (10 ng/mL) treatment for different periods of time. Inflammatory proteins and signaling molecules including inducible nitric oxide synthase, intracellular cell adhesion molecule-1, vascular cell adhesion molecule-1 (VCAM-1), cyclooxygenase 2 (COX2), nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPKs), and TNFα receptor 1 (TNFR1) were measured by qRT-PCR or western blotting; soluble TNFR1 level and NADPH oxidase activity were determined by Elisa kits; superoxide was measured by dihydroethidium staining. Only V-F treatment inhibited the expression of VCAM-1 and COX2, via suppressing NF-κB and p38 MAPK signaling, respectively, while reduced oxidative stress via the inhibition of NADPH oxidase activity; V-F treatment attenuated both gene and protein expressions of TNFR1.

CONCLUSION

V-F treatment ameliorated TNFα-induced endothelial inflammation and oxidative stress possibly via the inhibition of TNFR1 signaling, suggesting its potential as a functional food ingredient or nutraceutical in the prevention and treatment of hypertension and cardiovascular diseases. This article is protected by copyright. All rights reserved.