At Eyekandi, we are very open minded about ‘expanding our mind’s capacities’ within a framework of legalities. When articles are written about inhaled nanoparticles and therapeutic peptides, we’re all over it, and want to share it with you all too.
‘Never give up on drug delivery ideas’ – that’s one of the big points Mr Derek Lowe gets out of this paper. The authors, part of a multi-centre team from sites in Italy and Germany, have previously shown that calcium phosphate nanoparticles could be a good carrier for delicate cargo such as microRNAs.
MicroRNAs are small non-coding RNA molecules (containing about 22 nucleotides) which can be found in plants, animals and some viruses, that functions in RNA silencing and post-transcriptional regulation of gene expression…
Such things tend to get degraded pretty quickly in the bloodstream; our bodies do not particularly want lots of nucleic acid strands floating around between the organs. Therapeutic peptides suffer from similar disadvantages – anyone working on one usually ends up spending lots of time modifying the original peptide structure to keep it around long enough in the body in order for it to be effective.
This paper shows that the CaP nanoparticles are effective carriers of therapeutic peptides, but what’s alarming is that they show them working through inhalation. What gave them this idea? Air pollution! Here is an excerpt from the paper so you can see what we’re talking about:
The rationale for the use of this unconventional administration route for targeting of the heart is based on the concepts that (i) during respiration the oxygenated blood moves from the pulmonary circulation first to the heart via the pulmonary vein and (ii) combustion-derived nanoparticles and ultrafine particulates inhaled through polluted air were recently shown by us (16) and others (17) to be present in the heart and causally associated with cardiac arrhythmia and dysfunction, suggesting that inhaled nanoparticles are deposited in the heart. Furthermore, CaPs can protect peptides from immediate enzymatic degradation and, because of their negative surface charge, provide cellular permeability via the membrane internalization.
It’s not over yet
There are a lot of issues which need to be addressed still, as the paper itself makes pretty clear. One thing is for sure, as with all inhalation routes, you have to wonder about the variation in lung function, both in healthy and diseased patients. Long-term studies of the effects on lung tissue would be needed, as well as a lot more pharmocokinetic work in general.
The Eyekandi team are currently expanding their horizons and knowledge about various interesting topics, and we’d appreciate your thought!