Exercise is one of the external factors associated with impairment of intestinal integrity, possibly leading to increased permeability and altered absorption. Here, we aimed to examine to what extent endurance exercise in the glycogen‐depleted state can affect intestinal permeability toward small molecules and protein‐derived peptides in relation to markers of intestinal function. Eleven well‐trained male volunteers (27 ± 4 years) ingested 40 g of casein protein and a lactulose/rhamnose (L/R) solution after an overnight fast in resting conditions (control) and after completing a dual – glycogen depletion and endurance – exercise protocol (first protocol execution). The entire procedure was repeated 1 week later (second protocol execution). Intestinal permeability was measured as L/R ratio in 5 h urine and 1 h plasma. Five‐hour urine excretion of betacasomorphin‐7 (BCM7), postprandial plasma amino acid levels, plasma fatty acid binding protein 2 (FABP‐2), serum pre‐haptoglobin 2 (preHP2), plasma glucagon‐like peptide 2 (GLP2), serum calprotectin, and dipeptidylpeptidase‐4 (DPP4) activity were studied as markers for excretion, intestinal functioning and recovery, inflammation, and BCM7 breakdown activity, respectively. BCM7 levels in urine were increased following the dual exercise protocol, in the first as well as the second protocol execution, whereas 1 h‐plasma L/R ratio was increased only following the first exercise protocol execution. FABP2, preHP2, and GLP2 were not changed after exercise, whereas calprotectin increased. Plasma citrulline levels following casein ingestion (iAUC) did not increase after exercise, as opposed to resting conditions. Endurance exercise in the glycogen depleted state resulted in a clear increase of BCM7 accumulation in urine, independent of DPP4 activity and intestinal permeability. Therefore, strenuous exercise could have an effect on the amount of food‐derived bioactive peptides crossing the epithelial barrier. The health consequence of increased passage needs more in depth studies.
DOCUMENT
IL22 is an important cytokine involved in the intestinal defense mechanisms against microbiome. By using ileum-derived organoids, we show that the expression of anti-microbial peptides (AMPs) and anti-viral peptides (AVPs) can be induced by IL22. In addition, we identified a bacterial and a viral route, both leading to IL22 production by T cells, but via different pathways. Bacterial products, such as LPS, induce enterocyte-secreted SAA1, which triggers the secretion of IL6 in fibroblasts, and subsequently IL22 in T cells. This IL22 induction can then be enhanced by macrophage-derived TNFα in two ways: by enhancing the responsiveness of T cells to IL6 and by increasing the expression of IL6 by fibroblasts. Viral infections of intestinal cells induce IFNβ1 and subsequently IL7. IFNβ1 can induce the expression of IL6 in fibroblasts and the combined activity of IL6 and IL7 can then induce IL22 expression in T cells. We also show that IL22 reduces the expression of viral entry receptors (e.g. ACE2, TMPRSS2, DPP4, CD46 and TNFRSF14), increases the expression of anti-viral proteins (e.g. RSAD2, AOS, ISG20 and Mx1) and, consequently, reduces the viral infection of neighboring cells. Overall, our data indicates that IL22 contributes to the innate responses against both bacteria and viruses.
DOCUMENT
Understanding taste is key for optimizing the palatability of seaweeds and other non-animal-based foods rich in protein. The lingual papillae in the mouth hold taste buds with taste receptors for the five gustatory taste qualities. Each taste bud contains three distinct cell types, of which Type II cells carry various G protein-coupled receptors that can detect sweet, bitter, or umami tastants, while type III cells detect sour, and likely salty stimuli. Upon ligand binding, receptor-linked intracellular heterotrimeric G proteins initiate a cascade of downstream events which activate the afferent nerve fibers for taste perception in the brain. The taste of amino acids depends on the hydrophobicity, size, charge, isoelectric point, chirality of the alpha carbon, and the functional groups on their side chains. The principal umami ingredient monosodium l-glutamate, broadly known as MSG, loses umami taste upon acetylation, esterification, or methylation, but is able to form flat configurations that bind well to the umami taste receptor. Ribonucleotides such as guanosine monophosphate and inosine monophosphate strongly enhance umami taste when l-glutamate is present. Ribonucleotides bind to the outer section of the venus flytrap domain of the receptor dimer and stabilize the closed conformation. Concentrations of glutamate, aspartate, arginate, and other compounds in food products may enhance saltiness and overall flavor. Umami ingredients may help to reduce the consumption of salts and fats in the general population and increase food consumption in the elderly.
MULTIFILE
Chemo-enzymatic peptide synthesis is unique in enabling the fast and sustainable synthesis of cyclic peptides, complex peptides and functionalized mini-proteins. The starting materials are routinely obtained by solid-phase peptide synthesis. One of the starting materials requires an oxo-ester functionality for recognition by the enzymes active site. The SPPS-based synthesis of the oxo-ester functionality still suffers from significant byproduct formation and low overall synthesis yields. The solution to this is introduction of the oxo-ester functionality at the end of the SPPS via a so-called Passerini reaction. Such a process does not only result in a more efficient production of cyclic or long peptides, but also expand the scope towards proteins derived from biological synthesis (i.e. recombinant proteins). To highlight the relevance of this proposed methodology, we will demonstrate a site-selective modification of the pharmaceutically important drug insulin.
Biotherapeutic medicines such as peptides, recombinant proteins, and monoclonal antibodies have successfully entered the market for treating or providing protection against chronic and life-threatening diseases. The number of relevant commercial products is rapidly increasing. Due to degradation in the gastro-intestinal tract, protein-based drugs cannot be taken orally but need to be administered via alternative routes. The parenteral injection is still the most widely applied administration route but therapy compliance of injection-based pharmacotherapies is a concern. Long-acting injectable (LAI) sustained release dosage forms such as microparticles allow less frequent injection to maintain plasma levels within their therapeutic window. Spider Silk Protein and Poly Lactic-co-Glycolic Acid (PLGA) have been attractive candidates to fabricate devices for drug delivery applications. However, conventional microencapsulation processes to manufacture microparticles encounter drawbacks such as protein activity loss, unacceptable residual organic solvents, complex processing, and difficult scale-up. Supercritical fluids (SCF), such as supercritical carbon dioxide (scCO2), have been used to produce protein-loaded microparticles and is advantageous over conventional methods regarding adjustable fluid properties, mild operating conditions, interfacial tensionless, cheap, non-toxicity, easy downstream processing and environment-friendly. Supercritical microfluidics (SCMF) depict the idea to combine strengths of process scale reduction with unique properties of SCF. Concerning the development of long-acting microparticles for biological therapeutics, SCMF processing offers several benefits over conventionally larger-scale systems such as enhanced control on fluid flow and other critical processing parameters such as pressure and temperature, easy modulation of product properties (such as particle size, morphology, and composition), cheaper equipment build-up, and convenient parallelization for high-throughput production. The objective of this project is to develop a mild microfluidic scCO2 based process for the production of long-acting injectable protein-loaded microparticles with, for example, Spider Silk Protein or PLGA as the encapsulating materials, and to evaluate the techno-economic potential of such SCMF technology for practical & industrial production.
Biotherapeutic medicines such as peptides, recombinant proteins, and monoclonal antibodies have successfully entered the market for treating or providing protection against chronic and life-threatening diseases. The number of relevant commercial products is rapidly increasing. Due to degradation in the gastro-intestinal tract, protein-based drugs cannot be taken orally but need to be administered via alternative routes. The parenteral injection is still the most widely applied administration route but therapy compliance of injection-based pharmacotherapies is a concern. Long-acting injectable (LAI) sustained release dosage forms such as microparticles allow less frequent injection to maintain plasma levels within their therapeutic window. Spider Silk Protein and Poly Lactic-co-Glycolic Acid (PLGA) have been attractive candidates to fabricate devices for drug delivery applications. However, conventional microencapsulation processes to manufacture microparticles encounter drawbacks such as protein activity loss, unacceptable residual organic solvents, complex processing, and difficult scale-up. Supercritical fluids (SCF), such as supercritical carbon dioxide (scCO2), have been used to produce protein-loaded microparticles and is advantageous over conventional methods regarding adjustable fluid properties, mild operating conditions, interfacial tensionless, cheap, non-toxicity, easy downstream processing and environment-friendly. Supercritical microfluidics (SCMF) depict the idea to combine strengths of process scale reduction with unique properties of SCF. Concerning the development of long-acting microparticles for biological therapeutics, SCMF processing offers several benefits over conventionally larger-scale systems such as enhanced control on fluid flow and other critical processing parameters such as pressure and temperature, easy modulation of product properties (such as particle size, morphology, and composition), cheaper equipment build-up, and convenient parallelization for high-throughput production. The objective of this project is to develop a mild microfluidic scCO2 based process for the production of long-acting injectable protein-loaded microparticles with, for example, Spider Silk Protein or PLGA as the encapsulating materials, and to evaluate the techno-economic potential of such SCMF technology for practical & industrial production.
