How to Develop Anti-aging Therapies for

Canine Aging Biology Chapter 2 How does aging affect dogs?

Aging impacts dogs in a multiplicity of ways, They may also exhibit a loss of and these impacts reduce both lifespan (the hearing, limping or other signs of number of years a lives) and healthspan discomfort, and a general decline in (the number of years free of significant enthusiasm and energy. disease or disability). Most of us can easily tell a dog is old through a gestalt assessment of appearance, movement, and demeanor without being able to detail all the specific features that signal age.

Older dogs experience diminished physical One interesting challenge for canine health and functional capacity, decreased aging science is to be able to break resilience and resistance to stress and disease, this assessment down into and undesirable changes in behavior and components and identify specific social functioning. Aging also affects the bond markers of physical aging. This would between dogs and their human family be especially useful since not all dogs members and imposes emotional, financial, age in the same way or at the same and other burdens on caregivers. time, so biological age isn’t exactly matched with chronological age. Anti-aging therapies have the potential to mitigate all of these impacts by targeting We can tell when a dog is “old,” but the underlying mechanisms rather than what we are really seeing is their just the specific physical or behavioral biological age, not how many years manifestations of aging. they have lived.

The most familiar signs of aging in dogs are A six-year-old , for visible physical changes, such as greying and example, may look a lot older than a thinning of hair, loss of muscle, and clouding ten-year-old miniature of the eyes. parents also frequently notice because giant-breed dogs age changes in physical function. Our dogs may be physically faster and sooner than less active or have difficulty going up and small-breed dogs. down stairs or walking on slippery floors.

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Having tools to tell us the true biological age of individual dogs would help us understand how and why dogs age differently and also help us to measure the impact of anti-aging treatments.

Not all physical changes that occur with aging are visible, of course. Changes in the structure and function of internal organs have significant health effects even though they are invisible.

Old dogs may have less energy, less strength, less tolerance for exercise, less resilience in the face of physical stress, such as heat or cold, and less resistance to disease. Chronic invisible health problems, such as arthritis and other inflammatory diseases, kidney disease, heart disease, and many others become more common with aging, and these can seriously degrade comfort and quality of life.

One of the most common diseases of aging, and one of the leading causes of death in old dogs, is .

The details of how cancer happens are complex and vary some with different types of cancer. However, age-related damage to DNA and other components of cells, as well as changes in functioning and the internal environment of the body all make cancer more likely to appear and to progress to the point of clinical disease as dogs age. One of the exciting aspects of anti-aging medicine is that by targeting the general aging changes that support development of cancer, it may be possible to prevent many different kinds of at once, rather than having to target the specific mechanisms behind the development of each type separately.

Another common and critical impact of aging in dogs is the multitude of changes in behavior often seen.

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Ultimately, these changes may lead to Canine Cognitive Dysfunction (CCD), a phenomenon very similar to and some types of Alzheimer’s disease in humans.

This condition disrupts sleeping patterns, social relationships, and housetraining and increases fear and confusion, which all seriously undermine both the quality of life for our dogs and the human-animal bond between dogs and their family. These changes often lead to euthanasia even for dogs in otherwise good physical health. Slowing the aging changes in the brain that lead to undesirable behaviors and CCD would have a significant positive impact on both healthspan and lifespan in dogs.

disrupted sleep

confusion & panic disrupted relationships & household training

Signs of Canine Cognitive Dysfunction

Bottom Line

Aging leads to numerous physical and behavioral changes in dogs. Some of these are visible, such as greying of the hair, and others are hidden, but the accumulation of these changes eventually undermines the health and quality of life of aging dogs. Aging is also the number one risk factor for many diseases that seem, on the surface, unrelated. Cancer, kidney disease, heart disease, and dementia are all diagnosed and treated differently, but they are all more likely because of changes associated with aging.

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How to Develop Anti-aging Therapies for Dogs