TY - JOUR

T1 - Barrier properties of ex vivo porcine intestinal mucus are highly independent of isolation and storage conditions

AU - Støvring Mortensen, Janni

AU - Saaby, Lasse

AU - Harloff-Helleberg, Stine

AU - Mørck Nielsen, Hanne

N1 - Funding Information: Jannie Jørgensen, Charlotte Fink and the Department of Experimental Medicine (University of Copenhagen) are greatly acknowledged for providing pig intestines. Laboratory technician Karina Vissing, scholar student Sylvester Petersen and Master student Lasse Krog (Department of Pharmacy, University of Copenhagen) are acknowledged for their help with mucus isolation. This work was supported by Novo Nordisk Foundation (Grand Challenge Programme; NNF16OC0021948), Innovative Medicines Initiative Joint Undertaking (European Union’s Seventh Framework program FP7/2007-2013 and EFPIA: 115363) and the Carlsberg Foundation. Funding Information: Jannie J?rgensen, Charlotte Fink and the Department of Experimental Medicine (University of Copenhagen) are greatly acknowledged for providing pig intestines. Laboratory technician Karina Vissing, scholar student Sylvester Petersen and Master student Lasse Krog (Department of Pharmacy, University of Copenhagen) are acknowledged for their help with mucus isolation. This work was supported by Novo Nordisk Foundation (Grand Challenge Programme; NNF16OC0021948), Innovative Medicines Initiative Joint Undertaking (European Union's Seventh Framework program FP7/2007-2013 and EFPIA: 115363) and the Carlsberg Foundation. Publisher Copyright: © 2022 The Author(s)

PY - 2022

Y1 - 2022

N2 - Porcine intestinal mucus (PIM) is often utilized as an ex vivo mucus model in mucus interaction studies. However, numerous isolation procedures and storage conditions for PIM are reported, yet their potential impact on preserving the critical properties of PIM remains unknown. This study investigated the effect of isolation procedures (rinsing and anatomical site of mucus isolation) and storage conditions (−20 °C, −80 °C, snap frozen in liquid nitrogen prior to storage at −80 °C, or freeze-dried followed by storage at room temperature and reconstitution) of PIM in regard to the permeation of fluorescein-isothiocyanate-labelled dextran (FD) macromolecules of 4, 40 and 150 kDa, rheological properties as well as pH, osmolality, protein and water content. Rinsing intestines with tap water or phosphate-buffered saline as well as isolating PIM from different regions of the first five meters of the proximal jejunum did not affect the pH or osmolality of isolated PIM. The permeation of FD4, FD40 and FD150 through stored PIM was similar to permeation through fresh PIM. The rheological properties of stored PIM were similar to properties of fresh PIM. Osmolality, protein and water content were similar in stored and fresh PIM whereas pH decreased with 0.3 unit for all stored PIMs. Overall, PIM samples stored at −20°, −80 °C, snap frozen or freeze-dried were found to have similar properties to freshly isolated PIM and can all be considered good alternatives to fresh PIM for mucus studies.

AB - Porcine intestinal mucus (PIM) is often utilized as an ex vivo mucus model in mucus interaction studies. However, numerous isolation procedures and storage conditions for PIM are reported, yet their potential impact on preserving the critical properties of PIM remains unknown. This study investigated the effect of isolation procedures (rinsing and anatomical site of mucus isolation) and storage conditions (−20 °C, −80 °C, snap frozen in liquid nitrogen prior to storage at −80 °C, or freeze-dried followed by storage at room temperature and reconstitution) of PIM in regard to the permeation of fluorescein-isothiocyanate-labelled dextran (FD) macromolecules of 4, 40 and 150 kDa, rheological properties as well as pH, osmolality, protein and water content. Rinsing intestines with tap water or phosphate-buffered saline as well as isolating PIM from different regions of the first five meters of the proximal jejunum did not affect the pH or osmolality of isolated PIM. The permeation of FD4, FD40 and FD150 through stored PIM was similar to permeation through fresh PIM. The rheological properties of stored PIM were similar to properties of fresh PIM. Osmolality, protein and water content were similar in stored and fresh PIM whereas pH decreased with 0.3 unit for all stored PIMs. Overall, PIM samples stored at −20°, −80 °C, snap frozen or freeze-dried were found to have similar properties to freshly isolated PIM and can all be considered good alternatives to fresh PIM for mucus studies.

KW - Collection of mucus

KW - Composition

KW - Jejunum mucus

KW - Permeability

KW - Rheology

KW - Stability

U2 - 10.1016/j.ejpb.2022.03.015

DO - 10.1016/j.ejpb.2022.03.015

M3 - Journal article

C2 - 35364256

AN - SCOPUS:85128229925

VL - 174

SP - 106

EP - 110

JO - European Journal of Pharmaceutics and Biopharmaceutics

JF - European Journal of Pharmaceutics and Biopharmaceutics

SN - 0939-6411

ER -