Related Experiment Video
Updated: Aug 25, 2026

Antigens Protected Functional Red Blood Cells By The Membrane Grafting Of Compact Hyperbranched Polyglycerols
Published on: January 2, 2013
P-glycoprotein function in the elderly
Stefanie S Brenner1, Ulrich Klotz
1Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376 Stuttgart, Germany.
Objective:
The MDR1-encoded P-glycoprotein (Pgp) represents the best-studied membraneous efflux pump defending the body against xenobiotics. Various polymorphisms (single nucleotide polymorphisms; SNPs) in the MDR1 gene have been identified, and a silent mutation in exon 26 (C3435T) has been correlated with duodenal expression of Pgp, which might affect the disposition of certain drugs. The C3435T SNP has been shown to be linked to another SNP (G2677T/A) in exon 21 which leads to an amino acid exchange. So far, the influence of age on Pgp function has been neglected. As the function of Pgp might be altered in advanced age, we investigated in groups of fit and frail elderly subjects whether the efflux of the Pgp-probe rhodamine 123 from CD56(+) natural killer cells was age dependent and whether it was affected by the two SNPs.
Methods:
Leukocytes were isolated from blood of 18 healthy elderly subjects (mean age 69 years) and 20 geriatric frail patients (mean age 78 years) and data compared with 21 previously studied young healthy Caucasian individuals (mean age 33 years). Subjects were homozygous for either CC- or TT-genotype (SNP C3435T) and additionally differentiated according to genotype GG or TT of the SNP G2677T. Using flow cytometry, rhodamine fluorescence was monitored in CD56(+) cells.
Results:
In contrast to the young controls, in both elderly populations no significant difference between the CC and TT genotypes (exon 26) could be observed in rhodamine fluorescence. Furthermore, only for the TT genotype (exon 26) did frail elderly demonstrate some reduced Pgp function ( P=0.03) if compared with the young healthy subjects. If the three groups were compared independent of the genotype, no age effects were observed. For all assessed genotypes, there was no significant difference between fit and frail elderly subjects.
Conclusion:
Aging and frailty have apparently only a minor impact on this validated cellular Pgp model and it could be assumed that function of Pgp is quite well preserved in patients of advanced age.
More Related Videos
08:49Printed Glycan Array: A Sensitive Technique for the Analysis of the Repertoire of Circulating Anti-carbohydrate Antibodies in Small Animals
Published on: February 14, 2019
10:25Monitoring of Ubiquitin-proteasome Activity in Living Cells Using a Degron (dgn)-destabilized Green Fluorescent Protein (GFP)-based Reporter Protein
Published on: November 10, 2012
Related Concept Videos
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Metabolism
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Excretion
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Absorption
Proteoglycans
Protein Glycosylation
Glycosylation occurs in...
Matrix Proteoglycans and Glycoproteins