跳至主要内容

Sodium caprate enables the blood pressure-lowering effect of Ile-Pro-Pro and Leu-Lys-Pro in spontaneously hypertensive rats by indirectly overcoming PepT1 inhibition

Author:John P.Gleeson, Jesús M.Frías, Sinéad M.Ryan, David J.Brayden   《European Journal of Pharmaceutics and Biopharmaceutics》


ABSTRACTS
The tripeptides, Ile-Pro-Pro (IPP) and Leu-Lys-Pro (LKP), inhibit angiotensin-converting enzyme (ACE) resulting in lowered blood pressure. Our hypothesis was that the medium chain fatty acid permeation enhancer, sodium caprate (C10), may prevent the decrease in permeability of the tripeptides when PepT1 is inhibited by glycyl-sarcosine (Gly-Sar), a situation that may occur in the presence of food hydrolysates. Using Caco-2 monolayers and isolated rat jejunal tissue, the apparent permeability coefficients (Papp) of [3H]-IPP and [3H]-LKP were assessed in the presence of Gly-Sar with and without C10. Gly-Sar decreased the Papp of both tripeptides across monolayers and isolated jejunal tissue, but C10 restored it. C10likely increased the paracellular permeability of the tripeptides, as indicated by immunofluorescence changes in tight junction proteins in Caco-2 monolayers accompanied by a concentration-dependent decrease in transepithelial electrical resistance (TEER). [3H]-IPP and [3H]-LKP were orally-gavaged to normal rats with Gly-Sar, C10, or with a mixture. Plasma levels of both peptides were reduced by Gly-Sar to less than half that of the levels detected in its absence, but were restored when C10 was co-administered. In spontaneously hypertensive rats (SHRs), unlabelled IPP and LKP lowered blood pressure when delivered either by i.v. or oral routes. Oral gavage of Gly-Sar reduced the hypotensive action of peptides in SHRs, but the effect was restored in the presence of C10. In conclusion, there was a reduction in the hypotensive effects of IPP and LKP in SHRs when intestinal PepT1 was inhibited by Gly-Sar, but C10 may circumvent this by enhancing paracellular permeability.

Graphical abstract


KEY WORDS
Intestinal peptide transport; PepT1; Nutraceuticals; Antihypertensive agents; Intestinal permeation enhancers; Sodium caprate
SCREENSHOT

RELATED PRODUCTS
IPP (PubChem CID: 9949212) and LKP (PubChem CID: 24978508) were obtained from China Peptides (China)
CHAINING
https://www.sciencedirect.com/science/article/abs/pii/S0939641117308986


评论

此博客中的热门博文

The Catalytically Inactive Mutation of the Ubiquitin-Conjugating Enzyme CDC34 Affects its Stability and Cell Proliferation

Author:Xun Liu, Yang Zhang, Zhanhong Hu, Qian Li, Lu Yang,  Guoqiang Xu     《The Protein Journal》 ABSTRACTS The ubiquitin proteasome system (UPS) plays important roles in the regulation of protein stability, localization, and activity. A myriad of studies have focused on the functions of ubiquitin ligases E3s and deubiquitinating enzymes DUBs due to their specificity in the recognition of downstream substrates. However, the roles of the most ubiquitin-conjugating enzymes E2s are not completely understood except that they transport the activated ubiquitin and form E2–E3 protein complexes. Ubiquitin-conjugating enzyme CDC34 can promote the degradation of downstream targets through the UPS whereas its non-catalytic functions are still elusive. Here, we find that mutation of the catalytically active cysteine to serine (C93S) results in the reduced ubiquitination, increased stability, and attenuated degradation rate of CDC34. Through semi-quantitative proteom...

A Quasi-direct LC-MS/MS-based Targeted Proteomics Approach for miRNA Quantification via a Covalently Immobilized DNA-peptide Probe

Author:Liang Liu, Qingqing Xu, Shuai Hao & Yun Chen     《Scientific Reports》 ABSTRACTS MicroRNAs (miRNAs) play a vital role in regulating gene expression and are associated with a variety of cancers, including breast cancer. Their distorted and unique expression is a potential marker in clinical diagnoses and prognoses. Thus, accurate determination of miRNA expression levels is a prerequisite for their applications. However, the assays currently available for miRNA detection typically require pre-enrichment, amplification and labeling steps, and most of the assays are only semi-quantitative. Therefore, we developed a quasi-direct liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based targeted proteomics approach to quantify target miRNA by innovatively converting the miRNA signal into the mass response of a reporter peptide  via  a covalently immobilized DNA-peptide probe. Specifically, the probe containing the targeted proteomics-...

Preparation of an antimicrobial surface by direct assembly of antimicrobial peptide with its surface binding activity

Author:Junjian Chen, Yuchen Zhu, Yancheng Song, Lin Wang,  Jiezhao Zhan, Jingcai He, Jian Zheng, Chunting Zhong, Xuetao Shi, Sa Liu, Li Ren and Yingjun Wang     《Journal of Materials Chemistry B》 ABSTRACTS Antimicrobial peptides (AMPs) are a broad prospect for clinical application against bacterial infections of biomaterials. However, a bottleneck exists as there is a lack of simple technology to prepare AMPs on biomaterials with sufficient activity, as the activity of AMP is dependent on the correct orientation on the biomaterial. In the present study, based on the conventional AMP (Tet213: KRWWKWWRRC) and surface binding peptide (SKHKGGKHKGGKHKG), we designed an Anchor-AMP that could be directly assembled onto the surface of the biomaterial and also showed excellent antimicrobial activity. By characterizing the surface using a quartz crystal microbalance with dissipation (QCM-D), contact angle, atom force microscopy (AFM) and X-ray photoelectron spectr...