Jun 142012

Why CCD or ‘Doggie Dementia’?

CCD is very distressing to the dog’s owner and family. Their well-loved pet will begin to wander and pace, appear lost, get stuck behind furniture, stare aimlessly at the walls, and lose continence. Perhaps most sadly, dogs with CCD seem to forget their connection with the people they have lived with for many years. About 12% of dogs older than 8 years of age are estimated to have CCD, and the likelihood of developing CCD rises dramatically with age. Click here to learn more including a video of a dog with CCD.

In order to properly diagnose CCD, we developed the Canine Cognitive Dysfunction Rating scale (CCDR) that also allows us to track a dog’s clinical change over time. In addition, our group  developed the Canine Sand Maze as a simple, fun and accurate method of assessing a dog’s working memory.

From a neuroscience perspective, CCD is very interesting because of  many parallels to human Alzheimer’s dementia (AD). Dogs with CCD share a similar pattern of clinical symptoms as human AD, develop similar brain pathology, and react to new drugs as do humans.

In short, CCD is a faithful model of human dementia. This means that if a treatment works (or doesn’t work) in dogs with CCD, we can expect similar effects in humans.


About our Cell Therapy – Replacing Lost Cells and Connections

One of the main obstacles for finding a cure for dementia is that by the time symptoms arise, millions of neurons (brain cells) and their interconnections (synapses) will have been lost.

For this reason, there has been increasing research interest in using neural stem cells (NSCs) to treat brain diseases. NSCs are a special kind of cell that can replicate almost indefinitely in a primitive state, and then mature and develop into any one of a number of different types of brain cells. Almost all the cells in our brains now originate from NSCs when we were in our mother’s womb.  Amazingly, research in the last 10-15 years has confirmed that there are a limited number of adult NSCs that persist in special regions of the brain throughout adult life and continue to produce new brain cells through a process called neurogenesis.

Our group has developed a way of producing new brain cells from a small sample of canine skin. We do this by converting adult skin stem cells (found in all mammalian skin) into a type of neural stem cell. In addition, we have transplanted these canine skin-derived NSCs into rats with age-related memory dysfunction, and shown that the memory problems are reversed and that cells survive and engraft into the rodent’s brain.

In all our rodent studies so far, transplantation of these cells has been safe – animals have shown no side effects from the treatment, nor developed brain tumors.

We are therefore at the exciting stage in our research where we aim to trial, for the first time, whether Canine Cognitive Dysfunction in older dogs can be reversed by brain transplantation of NSCs generated from a small sample of the dog’s own skin.


Our Hope

This trial is  unique. We now have the tools and technology to test a completely new treatment option for dogs with CCD. If successful, we hope this may lead to similar trials in humans with dementia. We therefore hope that the DOGS +CELLS Trial can ultimately help improve both canine and human health.


What is involved?

There are a number of steps. The figure below summarizes this sequence.

  1. At the University of Sydney Veterinary Teaching Hospital, your dog will be thoroughly checked and examined by a veterinarian in order to definitively diagnose CCD.
  2. Your dog’s memory will be tested using our Canine Sand Maze.
  3. Under anaesthesia, we will take a small (approximately 2x2cm) skin biopsy from your dog’s belly and undergo a MRI brain scan
  4. We will then grow a customised batch of Neural Stem Cells from your dog’s skin (takes about 1 month)
  5. Your dog will return to the Hospital, and under anaesthesia, we will inject the special skin-derived cells into your dog’s brain. Your dog will be monitored at the Hospital overnight, and then released back into your care.
  6. We will carry out simple clinical exams and the Canine Sand Maze at regular 3-month and 6-month interval to keep track of your dog’s progress.

For Interested Owners

This study has been approved by the University of Sydney Animal Ethics Committee (K00/7-2012/3/5796).

Before considering whether you may wish to volunteer your dog for this study, there are a number of issues to check. One of our staff would be happy to discuss these with you further. In general:

  1. You need to be prepared to bring your dog into our Veterinary Clinic on a number of occasions over a 6-12month period
  2. Your dog needs to have a confirmed CCD diagnosis. Click here to get an initial idea.
  3. Your dog needs to be otherwise fit enough to tolerate two rounds of general anaesthesia, including cell transplantation into the brain.

If you are interested in finding out more, please email us, or fill in the form below and one of our trial Veterinarians contact you shortly.


For Interested Students

Student opportunities include:

  • Working on a multi-disciplinary cutting-edge project with the chance to influence both veterinary practice as well as human health
  • Promoting clinical diagnosis guidelines for CCD amongst vets
  • Training on canine cognitive assessment
  • Training on canine neuroimaging
  • Experience in canine neurological examination
  • Flexible work schedule

Interested students should email their CV to michael.valenzuela@sydney.edu.au