Bioengineers had successfully regrow cartilage in a rabbit’s knee using piezoelectricity, which appears to be a secret to successfully regrowth robust, functional cartilage in mammalian joints. The study was published in the journal Science Translational Medicine.
Arthritis is a common and painful disease caused by damage to our joints. Normally pads of cartilage cushion those spots, but injuries or age-related changes can wear it away. As the cartilage deteriorates, the bone begins to hit bone, and everyday activities like walking become terribly painful.
Current therapeutic options include surgical procedures like replacing the damaged cartilage with a healthy piece taken from elsewhere in the body or a donor. The problem is that healthy cartilage is in limited supply and taking it from your own could injure the place it was taken from.
The researchers designed a tissue scaffold made out of nanofibers of poly-L lactic acid (PLLA), which is a biodegradable polymer often used to stitch up surgical wounds. This material has a property called piezo-electricity, which when squeezed produces a little burst of electrical current.
Movements such as walking can cause the PLLA scaffold to generate a weak but steady electrical field that encourages cells to colonize it and grow into cartilage, and the cartilage that grows is mechanically robust.
They tested the scaffold in the knee of an injured rabbit, and it was allowed to hop on a treadmill to exercise after the scaffold was implanted. The cartilage grow back normally, as predicted by the team.
“This is a fascinating result, but we need to test this in a larger animal,” one with a size and weight closer to a human, says Thanh Nguyen, one of the researchers. His lab would want to observe the animals treated for at least a year, probably two, to make sure the cartilage is durable.
University of Connecticut. (2022, January 12). Regrowing knee cartilage with an electric kick: Piezoelectricity is the secret to successfully regrowing robust, functional cartilage in mammalian joints. ScienceDaily. Retrieved January 25, 2022 from www.sciencedaily.com/releases/2022/01/220112145042.htm
Wild baby rabbits in the UK. A new virus, rabbit haemorrhagic disease virus type 2 has caused a second crash in Britain’s rabbit population. Photograph: Wild Dales Photography – Simon Phillpotts/Alamy