Stereochemistry as a determining factor for the effect of a cell-penetrating peptide on cellular viability and epithelial integrity

TY - JOUR

T1 - Stereochemistry as a determining factor for the effect of a cell-penetrating peptide on cellular viability and epithelial integrity

AU - Birch, Ditlev

AU - Christensen, Malene Vinther

AU - Stærk, Dan

AU - Franzyk, Henrik

AU - Nielsen, Hanne Mørck

PY - 2018/5/24

Y1 - 2018/5/24

N2 - Cell-penetrating peptides (CPPs) comprise efficient peptide-based delivery vectors. Owing to the inherent poor enzymatic stability of peptides, CPPs displaying partial or full replacement of L-amino acids with the corresponding D-amino acids might possess advantages as delivery vectors. Thus, the present study aims to elucidate the membrane- and metabolism-associated effects of L-Penetratin (L-PEN) and its corresponding all-D analog (D-PEN). These effects were investigated when exerted on hepatocellular (HepG2) or intestinal (Caco-2 and IEC-6) cell culture models. The head-to-head comparison of these enantiomeric CPPs included evaluation of their effects on cell viability and morphology, epithelial membrane integrity, and cellular ultrastructure. In all investigated cell models, a rapid decrease in cell viability, pronounced membrane perturbation and an altered ultrastructure were detected upon exposure to D-PEN. At equimolar concentrations, these observations were less pronounced or even absent for cells exposed to L-PEN. Both CPPs remained stable for at least 2 h during exposure to proliferating cells (cultured for 24 h), although D-PEN exhibited a longer half-life when compared with that of L-PEN when exposed to well-differentiated cell monolayers (cultured for 18–20 days). Thus, the stereochemistry of the CPP penetratin significantly influences its effects on cell viability and epithelial integrity when profiled against a panel of mammalian cells.

AB - Cell-penetrating peptides (CPPs) comprise efficient peptide-based delivery vectors. Owing to the inherent poor enzymatic stability of peptides, CPPs displaying partial or full replacement of L-amino acids with the corresponding D-amino acids might possess advantages as delivery vectors. Thus, the present study aims to elucidate the membrane- and metabolism-associated effects of L-Penetratin (L-PEN) and its corresponding all-D analog (D-PEN). These effects were investigated when exerted on hepatocellular (HepG2) or intestinal (Caco-2 and IEC-6) cell culture models. The head-to-head comparison of these enantiomeric CPPs included evaluation of their effects on cell viability and morphology, epithelial membrane integrity, and cellular ultrastructure. In all investigated cell models, a rapid decrease in cell viability, pronounced membrane perturbation and an altered ultrastructure were detected upon exposure to D-PEN. At equimolar concentrations, these observations were less pronounced or even absent for cells exposed to L-PEN. Both CPPs remained stable for at least 2 h during exposure to proliferating cells (cultured for 24 h), although D-PEN exhibited a longer half-life when compared with that of L-PEN when exposed to well-differentiated cell monolayers (cultured for 18–20 days). Thus, the stereochemistry of the CPP penetratin significantly influences its effects on cell viability and epithelial integrity when profiled against a panel of mammalian cells.

U2 - 10.1042/BCJ20180155

DO - 10.1042/BCJ20180155

M3 - Journal article

C2 - 29686042

SN - 0264-6021

VL - 475

SP - 1773

EP - 1788

JO - Biochemical Journal

JF - Biochemical Journal

IS - 10

ER -