A predictive in vitro model of the impact of drugs with anticholinergic properties on human neuronal and astrocytic systems.
The link between off-target anticholinergic effects of medications and acute cognitive impairment in older adults requires urgent investigation. We aimed to determine whether a relevant in vitro model may aid the identification of anticholinergic responses to drugs and the prediction of anticholinergic risk during polypharmacy. In this preliminary study we employed a co-culture of human-derived neurons and astrocytes (NT2.N/A) derived from the NT2 cell line. NT2.N/A cells possess much of the functionality of mature neurons and astrocytes, key cholinergic phenotypic markers and muscarinic acetylcholine receptors (mAChRs). The cholinergic response of NT2 astrocytes to the mAChR agonist oxotremorine was examined using the fluorescent dye fluo-4 to quantitate increases in intracellular calcium [Ca2+]i. Inhibition of this response by drugs classified as severe (dicycloverine, amitriptyline), moderate (cyclobenzaprine) and possible (cimetidine) on the Anticholinergic Cognitive Burden (ACB) scale, was examined after exposure to individual and pairs of compounds. Individually, dicycloverine had the most significant effect regarding inhibition of the astrocytic cholinergic response to oxotremorine, followed by amitriptyline then cyclobenzaprine and cimetidine, in agreement with the ACB scale. In combination, dicycloverine with cyclobenzaprine had the most significant effect, followed by dicycloverine with amitriptyline. The order of potency of the drugs in combination frequently disagreed with predicted ACB scores derived from summation of the individual drug scores, suggesting current scales may underestimate the effect of polypharmacy. Overall, this NT2.N/A model may be appropriate for further investigation of adverse anticholinergic effects of multiple medications, in order to inform clinical choices of suitable drug use in the elderly.
School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, United Kingdom.
Elizabeth K
EK
Woehrling
School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, United Kingdom.
H Rheinallt
HR
Parri
School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, United Kingdom.
Erin H Y
EH
Tse
Aston Research Centre into Healthy Ageing (ARCHA), Aston University, Birmingham, B4 7ET, United Kingdom.
Eric J
EJ
Hill
Aston Research Centre into Healthy Ageing (ARCHA), Aston University, Birmingham, B4 7ET, United Kingdom.
Ian D
ID
Maidment
Norwich Medical School, Faculty of Medicine and Health Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom.
G Christopher
GC
Fox
School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, United Kingdom.
Michael D
MD
Coleman
D000639:Amitriptyline / Q000494:pharmacology; D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D018678:Cholinergic Agents / Q000494:pharmacology; D018680:Cholinergic Antagonists / Q000494:pharmacology*; D004025:Dicyclomine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism*; D010095:Oxotremorine / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism
D018678:Cholinergic Agents; D018680:Cholinergic Antagonists; D005904:Glial Fibrillary Acidic Protein; D011976:Receptors, Muscarinic; D014404:Tubulin; D000639:Amitriptyline; D004025:Dicyclomine; D010095:Oxotremorine; D002118:Calcium