Search results for "PEPTIDE"

Evaluation of in vitro iron bioavailability in free form and as whey peptide-iron complexes

2018

Abstract Finding alternatives for food fortification in a bioavailable form of iron is needed because iron deficiency leads to several diseases. Iron solubility and in vitro iron absorption were evaluated in free and complexed forms, as iron salts or peptide-iron complexes. Whey peptide-iron complexes were synthesized with various ligands (whey protein hydrolysate; its fractions >5 kDa and 85%), only complexes that were synthesized with low-molecular-mass peptides (

Antimicrobial peptide–metal ion interactions – a potential way of activity enhancement

2018

Increasing bacterial and fungal drug resistance requires novel, effective antimicrobial treatments to be actively sought. Because of a general lack of resistance towards antimicrobial peptides (AMPs), they are being relied on as a novel class of therapeutics aiming to conquer drug-resistant bacteria and fungi. There are numerous ways in which AMPs might interact with pathogens, such as membrane disruption, production of ROS, inhibition of cell wall, nucleic acid and protein synthesis or by the withdrawal of essential metal ions. Biologically indispensable metal ions have a dual effect on the activity of antimicrobial peptides: (i) AMPs bind them, so that microbes cannot get enough metals es…

Bacterial Vegetative Insecticidal Proteins (Vip) from Entomopathogenic Bacteria

2016

SUMMARY Entomopathogenic bacteria produce insecticidal proteins that accumulate in inclusion bodies or parasporal crystals (such as the Cry and Cyt proteins) as well as insecticidal proteins that are secreted into the culture medium. Among the latter are the Vip proteins, which are divided into four families according to their amino acid identity. The Vip1 and Vip2 proteins act as binary toxins and are toxic to some members of the Coleoptera and Hemiptera. The Vip1 component is thought to bind to receptors in the membrane of the insect midgut, and the Vip2 component enters the cell, where it displays its ADP-ribosyltransferase activity against actin, preventing microfilament formation. Vip3…

2018

The cellular inhibitor of apoptosis 1 (cIAP1) is an E3-ubiquitin ligase that regulates cell signaling pathways involved in fundamental cellular processes including cell death, cell proliferation, cell differentiation and inflammation. It recruits ubiquitination substrates thanks to the presence of three baculoviral IAP repeat (BIR) domains at its N-terminal extremity. We previously demonstrated that cIAP1 promoted the ubiquitination of the E2 factor 1 (E2F1) transcription factor. Moreover, we showed that cIAP1 was required for E2F1 stabilization during the S phase of cell cycle and in response to DNA damage. Here, we report that E2F1 binds within the cIAP1 BIR3 domain. The BIR3 contains a s…

Age-dependent control of collagen-dependent platelet responses by thrombospondin-1 : Comparative analysis of platelets from neonates, children, adole…

2021

Platelet function is developmentally regulated. Healthy neonates do not spontaneously bleed, but their platelets are hypo-reactive to several agonists. The mechanisms underlying immature platelet function in neonates are incompletely understood. This critical issue remains challenging for the establishment of age-specific reference ranges. In this study, we evaluated platelet reactivity of five pediatric age categories, ranging from healthy full-term neonates up to adolescents (11–18 years) in comparison to healthy adults (&gt

Pharmacological disruption of the MID1/α4 interaction reduces mutant Huntingtin levels in primary neuronal cultures.

2017

Expression of mutant Huntingtin (HTT) protein is central to the pathophysiology of Huntington's Disease (HD). The E3 ubiquitin ligase MID1 appears to have a key role in facilitating translation of the mutant HTT mRNA suggesting that interference with the function of this complex could be an attractive therapeutic approach. Here we describe a peptide that is able to disrupt the interaction between MID1 and the α4 protein, a regulatory subunit of protein phosphatase 2A (PP2A). By fusing this peptide to a sequence from the HIV-TAT protein we demonstrate that the peptide can disrupt the interaction within cells and show that this results in a decrease in levels of ribosomal S6 phosphorylation a…

Mortality in COVID-19 disease patients: Correlating Association of Major histocompatibility complex (MHC) with severe acute respiratory syndrome 2 (S…

2020

Highlights • In addition to ethnicity, socio-economic factors, prior vaccinations and exposure to other coronaviruses, other factors need to be considered to explain geographical and regional variations in susceptibility, severity of clinical expression of COVID-19 disease and outcomes. • Differences in peptide binding of SARS-CoV-2 variants to MHC class II, but not to MHC class I alleles frequent in individuals with African, Asian or Caucasian descent could be identified. • Single mutations in the wildtype of SARS-CoV-2, the so called B strain or L strain impact on MHC presentation • Most likely there is selective pressure from MHC class II alleles in regard to binding of the ORF8 (L84S) v…

Evidence That Graves' Ophthalmopathy Immunoglobulins Do Not Directly Activate IGF-1 Receptors

2018

Background: Graves' ophthalmopathy (GO) pathogenesis involves thyrotropin (TSH) receptor (TSHR)-stimulating autoantibodies. Whether there are autoantibodies that directly stimulate insulin-like growth factor 1 receptors (IGF-1Rs), stimulating insulin-like growth factor receptor antibodies (IGFRAbs), remains controversial. This study attempted to determine whether there are stimulating IGFRAbs in patients with GO. Methods: Immunoglobulins (Igs) were purified from normal volunteers (NV-Igs) and patients with GO (GO-Igs). The effects of TSH, IGF-1, NV-Igs, and GO-Igs on pAKT and pERK1/2, members of pathways used by IGF-1R and TSHR, were compared in orbital fibroblasts from GO patients (GOFs) a…

Cardiovascular outcomes trials with incretin-based medications: a critical review of data available on GLP-1 receptor agonists and DPP-4 inhibitors

2020

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors are so called “incretin-based therapies” (IBTs) that represent innovative therapeutic approaches and are commonly used in clinical practice for the treatment of type 2 diabetes mellitus (T2DM). The cardiovascular outcome trials (CVOTs) have provided useful information that has helped to shape changes in clinical practice guidelines for the management of T2DM. At the same time, the mechanisms that may explain the nonglycemic and cardiovascular (CV) benefits of these medications are still being explored. A summary of the main findings from CVOTs performed to-date with particular emphasis on vari…

Influence of glucagon-like peptide 2 on energy homeostasis

2016

Glucagon like peptide-2 (GLP-2) is a gastrointestinal hormone released from enteroendocrine L-type cells together with glucagon like peptide-1 in response to dietary nutrients. GLP-2 acts through a specific receptor, the GLP-2 receptor, mainly located in the gut and in the brain. Classically, GLP-2 is considered a trophic hormone involved in the maintenance of intestinal epithelial morphology and function. This role has been targeted for therapies promoting repair and adaptive growth of the intestinal mucosa. Recently, GLP-2 has been shown to exert beneficial effects on glucose metabolism specially in conditions related to increased uptake of energy, such as obesity. Several actions of GLP-…