By Laura Liscum on behalf of the PBGVCA Health Committee
In August, the AKC Canine Health Foundation (CHF) sponsored the 2015 National Parent Club Canine Health Conference in St. Louis. Linda Murray and I attended the conference on behalf of the PBGVCA and the PBGV Health & Rescue Foundation, respectively. We both thought that it was a fabulous experience with excellent talks, abundant opportunities to interact with the speakers, and lots of free dog chow! Here is a synopsis of several presentations that we heard at the conference.
Stem Cells Therapy for Supraspinatus Tendonopathy.
Dogs injure ligaments and tendons while chasing bunnies in the field, running agility courses and roughhousing at doggie daycare. Like their owners, many dogs develop osteoarthritis after years of activity. The traditional surgical repair, medications and rehabilitation therapy have not always restored the injured dog to his/her pre-injury state. Two years ago, we heard Dr. Sherman Canapp describe his remarkable results when traditional treatment approaches are combined with stem cells or platelet-rich plasma therapy. His work continues to look very promising.
This year we heard Dr. Jennifer Barrett from Virginia-Maryland Regional College of Veterinary Medicine. Barrett described her collaborative studies with Canapp using stem cells and platelet-rich plasma to heal 57 agility dogs with shoulder injuries that had been lame for more than a yeardespite treatment with non-steroidal anti-inflammatory drugs, steroids and sessions in rehab. Dogs were treated with stem cells, which are undifferentiated cells that are able to divide and develop into specialized cells that repair and replenish adult tissues. They also treated the dogs with platelet-rich plasma isolated from the canine patient’s blood. Platelets are a natural source of bioactive proteins and growth factors that stimulate collagen formation and healing of tendons and ligaments. In fact, platelet rich plasma is currently being used to treat human and equine athletes. The dogs received pre-treatment analysis of gait and limb movement. Then stem cells and platelets were isolated and injected into the soft tissue lesions, guided by ultrasound.
The dog returned each month for ultrasound gait and limb movement analyses. The site of injury was examined by arthroscopy at 90 days. The outcomes of this study were very encouraging! The AKC CHF is now funding Drs. Barrett and Canapp to conduct the first randomized, placebocontrolled clinical trial of stem cells and platelet-rich plasma for supraspinatus tendon injury. They are having a difficult time enrolling enough dogs for the trial, so if you have an injured dog, please inquire.
Techniques to Treat Cartilage Disorders. Complaints about aching joints are not limited to the athletic canine. Couch potatoes can get injured too. In fact, 80 percent of all dogs have orthopedic joint disease at some point. One type of joint disease is called osteochondrosis, in which the joint’s cartilage becomes damaged. If a weakened flap of tissue breaks off, the piece may absorb minerals and harden. Imagine what it would feel like to have a pebble floating around in your joint! Unfortunately, joints do not regenerate healthy tissue very well. Dr. William Saunders, from Texas A&M, described a method for healing degenerated joints in which a plug of tissue is taken out of a non-weight-bearing portion of a dog’s healthy joint and grafted into the same dog’s damaged joint. This autograft can successfully restore function to the formerly damaged joint. However, this is like robbing Peter to pay Paul — the donor site now has a weakened cavity. Dr. Saunders’s goal is to develop a method to strengthen the donor site. His approach is to create replacement plugs made of porous polyethylene glycol and seeded with healthy bone-derived stem cells. In his preliminary studies, he placed these artificial plugs into the donor sites, and the stem cells within the plug populated the joint. This is an important step in bringing the autograft therapy method to the clinic.
Personalized Cancer Treatment.
Most treatment strategies for cancer use a standard approach in which all individuals with a particular cancer are treated with the same standard drug therapy. Unfortunately, this approach fails to take into account the molecular differences between individual cancers. Precision medicine is a new approach in which treatments are selected only after an individual’s tumor has been profiled to find specific gene mutations that led to their cancer.
Dr. Douglas Thamm of Colorado State University is investigating Toceranib, a therapeutic for mast-cell tumors that is used when surgery is not curative. Toceranib, marketed as Palladia, is the only dog-specific anti-cancer drug that is currently approved by the U.S. Food and Drug Administration. It acts by binding to a specific protein in tumor cells. Dr. Thamm hypothesizes that treatment with Toceranib will only be successful on dogs whose tumors are due to mutation of that specific protein. To test this hypothesis, Dr. Thamm has developed a rapid test that can be performed on fine-needle aspirates. The test can rapidly determine whether a dog’s mast-cell tumor has the mutation so that a therapeutic decision can be made within days. This test is the first step toward personalized medicine in the treatment of canine mast-cell tumors.
Atopic Dermatitis and the Mycobiome.
“You’ll Never Walk Alone” is a Rodgers and Hammerstein song from the musical Carousel. When he wrote the lyrics in 1945, Hammerstein had no way of knowing that when you walk through a storm, at least 100 trillion bacteria walk with you. In fact, 90 percent of our body’s cells are bacteria! We truly never walk alone. Fortunately, the microbes that colonize us are non-pathogenic symbiotic bacteria and fungi that are critical for our health. The abundance of these friendly microbes keeps the pathogenic organisms at bay.
Dr. Jan Suchodolski from Texas A&M is studying the canine mycobiome, which is the dog’s fungal community. He has determined that “the skin of dogs is inhabited by much more rich and diverse microbial communities than previously thought.” His recent publication [Hoffman, 2014] showed that each dog has a unique community of microorganisms, and each area of a dog’s skin harbors a unique selection of microbes. Healthy dogs have from 25 to 40 different species in their nostrils and up to 866 species in an ear! The composition of the microbial community did not appear to be influenced by dog age, sex, breed, itchiness, ear problems or indoor/outdoor environment. However, there was a significant difference when healthy dogs were compared to those with atopic dermatitis, or allergies. Dogs with allergies had fewer species of microbes than healthy dogs. Future work is needed to determine whether the reduced diversity of the skin mycobiome in allergic dogs isthe cause of, or the result of, the animal’s hypersensitivity to allergens. It is not known if the skin mycobiome shifts during allergic episodes. Finally, the possibility exists that restoring the microbe community to healthy levels will help treat atopic dermatitis.
Senior Cognition and Brain Aging.
Are you slower to get out of bed in the morning? Can’t remember who that person in front of you is? Finding it harder to negotiate a familiar environment? Have a decreased attention span and a loss of knowledge? Feeling anxious about all of these changes? These are questions that you should be asking your senior dog. From about six years of age on, your dog will begin to exhibit signs of brain aging that are so subtle that you may not notice them. Signs that are severe enough for you to notice include new fears or phobias, separation anxiety, soiling in the house, waking at night, vocalization and repetitive actions. Many owners do not report the first signs of aging to their vet because they think that nothing can be done. But there is evidence that early intervention may help.
Dr. Gary Landsberg from the North Toronto Veterinary Behaviour Specialty Clinic has extensive experience in testing cognition in senior dogs. Senior dogs get Alzheimer’s-like brain changes and have measurable deficits in learning and memory. When cognitive dysfunction is suspected, a vet must first rule out medical issues, and conduct neurological and sensory physical exams. Dr. Landsberg is also director of Veterinary Affairs at CanCog, a contract organization that specializes in non-invasive research on canine cognition and general behavior. His videos of the CanCog Beagle colony illustrated a typical cognitive test. First, let a dog learn a task such as quickly finding the food treat that is under the large box, but never under the small box. Once the task is learned, you present the dog with a reversal task by putting the treat under the small box. Young dogs quickly learn that the task has been reversed, whereas older dogs take significantly longer. But it turns out you can teach an old dog this new trick if you have provided the dog with an enriched environment. Dr. Landsberg said that you should make a senior dog work his/her brain everyday! He cited several pharmaceuticals that he prescribes for dogs that are showing cognitive dysfunction. He said that senior dogs show improvement with the medications individually and do even better when they are in combination. He encouraged owners to ask their vets for help. He also recommended two foods for dogs older than six; they are Hills b/d Canine and Purina Bright Minds (discussed below). Both have additives that help senior dogs maintain learning and memory skills.
Bright Mind Platform.
The brain is the most metabolically active organ in the body. At rest, the human brain uses up to 25 percent of the body’s energy even though it only accounts for 2 percent of the body’s mass. When challenged by a Sudoku puzzle, the energy needs go up. That energy is obtained from glucose that enters brain tissue from the blood. The situation is similar in dogs. Dr. Gary Penn, from the Nestlé Research Center, explained that dogs begin to show behavior signs of aging because their brains lose the ability to metabolize glucose around the age of 7. Investigators at the Nestlé Research Center explored alternative energy sources and found that adding medium chain triglycerides to the food increased the ability of dogs at the CanCog facility to perform cognitive tests. I was so convinced by the evidence that medium-chain triglycerides help maintain cognitive function that I bought a coconut-oil dietary supplement for myself. If only I could remember to take it!
The Human-Animal Bond/Quality of Life Scale.
If you are an avid reader of Saber Tails, that probably means that your passionate relationship to your PBGV(s) governs your life. From the house you buy and the car you drive, to the clothes you wear and places you vacation — PBGVs rule! This extraordinarily close human-animal bond makes it difficult when your dog is terminally ill. The keynote speaker for the CHF conference was Dr. Alice Villalobos, the former president of both the American Associationof Human Animal Bond Veterinarians and of the Society for Veterinary Medical Ethics. Dr. Villalobos has an animal oncology consultation service in Woodland Hills, Calif., and an animal hospice, called Pawspice, in Hermoso Beach, Calif. The Pawspice mission statement says, “Pawspice is committed to the highest standard of compassionate cancer treatment and end-of-life palliative care to advanced stage and terminal pets by providing a unique Quality of Life Care Program.”
According to Dr. Villalobos, we need to be able to distinguish between normal senior life and end of life in our pets. In the past, veterinarians were not trained to give pets palliative care; she is trying to change that. She has developed a quality of life scale that assesses seven characteristics, which are Hurt, Hunger, Hydration, Hygiene, Happiness, Mobility and More good days than bad days. The scale is intended to help caregivers and family to monitor and improve a pet’s well being, and help them know when palliative care and hospice may be warranted, rather than curative treatment. Dr. Villalobos stressed the importance of providing terminally ill pets all necessary medications, effective pain management, adequate nutrition and hydration, proper hygiene, assistance with mobility to maintain muscle mass and healthy joints, and contentment.
The Pawspice website (pawspice.com) has excellent resources for pet owners who are facing difficult end-of-life decisions. Go to the site and click on Library to find articles on Dr. Villalobos’s quality-of-ife scale or to view her seminar at the August 2015 Southern California Veterinary Medical Association Symposium. There is also information on many types of cancer and when it is time for euthanasia.
The 2015 National Parent Club Canine Health Conference also featured presentations on gastric dilatation volvulus (commonly known as bloat), intestinal inflammation, infectious diseases, brucellosis and seizures. You will read about those talks in a future issue of Saber Tails.