Molecular docking is widely used to predict the interaction
Molecular docking is widely used to predict the interaction between an enzyme and its inhibitors. This is a computational simulation approach that can be used as a tool to investigate the structure-activity relationship of ACE inhibitory peptides (Goodsell, 2009). It has been recently shown that ACE inhibitory peptides bind with ACE through various interactions, including hydrogen bonds, hydrophobic, van der Waals, electrostatic and metal acceptor interaction (Li et al., 2014). The inhibition of peptides derived from in vitro GI digestion of cooked chicken meat has not been well established. Therefore, better understanding of ACE inhibition of these peptides after digestion and absorption, and assessment of their activity at the molecular level are critical steps in the development of nutraceutical and pharmaceutical products from these peptides.
Materials and methods
Results and discussion
Conclusions The effectiveness of ACE inhibitory peptides under physiological condition greatly depends on permeability in their intact form. In this study, KPLL revealed the highest ACE inhibitory activity after transport through Caco-2 cells. KPLL was hydrolyzed by surface G007-LK enzymes to KP and LL, and the intact peptide as well as peptide fragments were transported to the basolateral layer. Enzyme inhibition kinetics and molecular docking studies illustrated that KPLL and KP exhibited mixed mode inhibition (Ki of 0.09 and 3.86 mM, respectively), while LL was a non-competitive inhibitor. K1 at N-terminus of KPLL is a key residue required for ACE inhibition. The findings obtained from this study warrant further in vivo investigation on hypotensive effect of KPLL.
Acknowledgments This work was financially supported by the Royal Golden Jubilee Scholarship (Grant No. PhD/0223/2552). Partial funding was also obtained from Suranaree University of Technology (SUT) and by the Office of the Higher Education Commission under NRU project of Thailand, and from the Natural Sciences & Engineering Research Council of Canada research grants to co-authors DDK and ECYL.
Introduction In this Special Section, Finkelhor (2017) provides the field with his perspective about the cautions needed for “widespread” screening of ACEs (Finkelhor, 2017). He asserts a lack of evidence-based interventions and questions the potential iatrogenic effects for persons who screen positive for ACEs. Interestingly, he also raises the question about what we should be screening for, in light of the 2015 publication, which recommended that ACEs assessment should include more than the 10 original exposures (Finkelhor, Shattuck, Turner, & Hamby, 2015). The current paper provides further discussion regarding Finkelhor’s cautions about ACEs screening. While there is a recognition that evidence-based interventions for ACEs are lacking, childhood trauma is a public health crisis; we are now at a juncture to act cautiously and ethically. Finkelhor (2017) cites examples of positive public health screening. In his article, he states verbatim: “One of the key principles in public health screening is that screening primarily has benefits when we have established interventions that mitigate some potential harmful outcome that the screening identifies (Stoto, Almario, & McCormick, 1999). Two positive examples are screening for smoking (Milch, Edmunson, Beshansky, Griffith, & Selker, 2004) and substance abuse (Babor et al., 2007). In both cases research has demonstrated that, when identified, brief counseling by physicians, and referrals to evidence based treatment programs can reduce these risk behaviors and improve health (Finkelhor, 2017).” Tobacco use is a modifiable behavior and it is correct to say that there are evidence-based interventions that warrant screening (US Public Health Service, 2008); screening for tobacco use is an intervention in and of itself. Tobacco use, in particular smoking, grabbed the attention of the medical and public health community with the release of the 1964 Surgeon General’s Report on Smoking and Health (https://www.cdc.gov/tobacco/data_statistics/sgr/index.htm). With comprehensive tobacco control programs and policies, the prevalence of smoking has significantly declined over the past six decades (Centers for Disease Control and Prevention, 2014). However, a substantial percent of adults still smoke, and eradication of smoking initiation among youth is not yet realized (US Department of Health & Human Services, 2014).