Cholecystokinin protects mouse liver against ischemia and reperfusion injury

Xin

et al. 2019

IJMS

Intestinal inflammation is an inflammatory disease resulting from immune dysregulation in the gut. It can increase the risk of enteric cancer, which is a common malignancy globally. As a new class of anti-inflammatory agents, native peptides have potential for use in the treatment of several intestinal inflammation conditions; however, their potential cytotoxicity and poor anti-inflammatory activity and stability have prevented their development. Hybridization has been proposed to overcome this problem. Thus, in this study, we designed a hybrid peptide (LL-37-TP5, LTP) by combing the active centre of LL-37 (13–36) with TP5. The half-life and cytotoxicity were tested in vitro, and the hybrid peptide showed a longer half-life and lower cytotoxicity than its parental peptides. We also detected the anti-inflammatory effects and mechanisms of LTP on Lipopolysaccharide (LPS)-induced intestinal inflammation in murine model. The results showed that LTP effectively prevented LPS-induced weight loss, impairment of intestinal tissues, leukocyte infiltration, and histological evidence of inflammation. Additionally, LTP decreased the levels of tumour necrosis factor-alpha, interferon-gamma, and interleukin-6; increased the expression of zonula occludens-1 and occludin; and reduced permeability in the jejunum of LPS-treated mice. Notably, LTP appeared to be more potent than the parental peptides LL-37 and TP5. The anti-inflammatory effects of LTP may be associated with the neutralization of LPS, inhibition of oxidative stress, and inhibition of the NF-κB signalling pathway. The findings of this study suggest that LTP might be an effective therapeutic agent for treating intestinal inflammation.

Section: Discussionmentioning

confidence: 99%

A Novel Peptide Ameliorates LPS-Induced Intestinal Inflammation and Mucosal Barrier Damage via Its Antioxidant and Antiendotoxin Effects

Xin

et al. 2019

IJMS

“…The activity of MPO is directly proportional to the neutrophil concentration in the inflamed tissue. Therefore, MPO activity is an index of neutrophil infiltration and inflammation (67). Consistent with this, jejunal MPO activity was markedly increased in LPS-treated mice, but pretreatment with LTA significantly reduced this effect.…”

Section: Discussionmentioning

confidence: 99%

Design and Development of a Novel Peptide for Treating Intestinal Inflammation

et al. 2019

Intestinal inflammatory disorders, such as inflammatory bowel disease (IBD), are associated with increased pro-inflammatory cytokine secretion in the intestines. Furthermore, intestinal inflammation increases the risk of enteric cancer, which is a common malignancy globally. Native anti-inflammatory peptides are a class of anti-inflammatory agents that could be used in the treatment of several intestinal inflammation conditions. However, potential cytotoxicity, and poor anti-inflammatory activity have prevented their development as anti-inflammatory agents. Therefore, in this study, we designed and developed a novel hybrid peptide for the treatment of intestinal inflammation. Eight hybrid peptides were designed by combining the active centers of antimicrobial peptides, including LL-37 (13-36), YW12D, innate defense regulator 1, and cathelicidin 2 (1-13) with thymopentin or the active center of thymosin alpha 1 (Tα1) (17-24). The hybrid peptide, LL-37-Tα1 (LTA), had improved anti-inflammatory activity with minimal cytotoxicity. LTA was screened by molecule docking and in vitro experiments. Likewise, its anti-inflammatory effects and mechanisms were also evaluated using a lipopolysaccharide (LPS)-induced intestinal inflammation murine model. The results showed that LTA prevented LPS-induced impairment in the jejunum epithelium tissues and infiltration of leukocytes, which are both histological markers of inflammation. Additionally, LTA decreased the levels of tumor necrosis factor-alpha, interferon-gamma, interleukin-6, and interleukin-1β. LTA increased the expression of zonula occludens-1 and occludin, and reduced permeability and apoptosis in the jejunum of LPS-treated mice. Additionally, its anti-inflammatory effect is associated with neutralizing LPS, binding to the Toll-like receptor 4-myeloid differentiation factor 2 (TLR4/MD-2) complex, and modulating the nuclear factor-kappa B signal transduction pathway. The findings of this study suggest that LTA may be an effective therapeutic agent in the treatment of intestinal inflammation.

“…However, the variation in bioactive CCKs is small in among species. In addition to mediating gallbladder contraction, pancreatic secretion, memory, and satiation [12, 13], CCK has also been shown to exert protective effects in the lung [14], kidney [15], liver [16] and heart through its receptors (CCK-AR/BR) in recent studies [17]. The multifunctionality of CCK suggests that it may have potential as a target in the evaluation and treatment of various diseases [18-20].…”

Section: Introductionmentioning

confidence: 99%

Cholecystokinin Expression in the Development of Postinfarction Heart Failure

Dong

Wang

et al. 2017

Cell Physiol Biochem

Background/Aims: Cholecystokinin (CCK) is expressed in cardiomyocytes and may also play an important role in cardiovascular regulation. Clinical studies have shown that plasma CCK levels are an independent marker of cardiovascular mortality in cardiac disease. However, whether the development of postinfarction heart failure is associated with changes in CCK expression is unknown. Methods: To investigate CCK expression patterns and the association between CCK expression and heart functional parameters, we randomized male Sprague-Dawley rats into myocardial infarction (MI) or sham operation (SO) groups. CCK expression levels were assessed by western blotting, immunohistochemistry, real-time polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA) at different time points (2, 4 or 6 weeks) after surgery. Brain natriuretic peptide (BNP) concentrations were determined using Western blotting and ELISA, myocardial morphology was assessed by microscopy. Results: Plasma CCK and BNP levels were significantly increased in all the MI groups compared with the corresponding SO groups. However, the degree to which myocardial CCK mRNA and protein expression levels were increased the MI groups compared with the SO groups was greater in the 4- and 6-week groups than in the 2-week group. Furthermore, plasma CCK levels were positively correlated with BNP concentrations and left ventricular end-systolic diameter (LVDs) and significantly negatively correlated with the ejection fraction (EF) and shortening fraction (SF) in model animals. Conclusions: Heart failure progression after infarction is associated with upregulated CCK levels; thus, CCK may be useful as a novel marker of heart failure.