By Emily Dickson, MS
As a quick refresher, cartilage has two main components: 1) Chondrocytes, i.e. the master builder and regulator cells, and 2) the extracellular matrix, which contains collagen and proteoglycans.
Proteoglycans are made up of a core protein and a glycosaminoglycan side chain. I know these are weird words, but I’m sure you have heard of chondroitin sulfate (CS); you may even have some form of CS in your home or barn already. CS is the primary glycosaminoglycan in cartilage.
The really cool thing about proteoglycans is that they act as shock absorbers and compressive strength for the joint. No wonder we all seem to be crazy about supplementing with chondroitin--It makes sense we would want to provide as much cushion to our horses’ joints as possible.
For reference, glucosamine, another common joint supplement ingredient, also occurs naturally in the body, and acts as a building block for proteoglycans and hyaluronic acid. Both are important, but CS is actually a glycosaminoglycan (building block) in cartilage, while glucosamine which is basically food for the joint.
Hopefully you are starting to see how this is all related.
The reason the cartilage proteoglycan network is a big deal is because it is constantly regenerating, unlike collagen which has very limited abilities. And we know for sure that a healthy level of exercise actually stimulates proteoglycan synthesis. The adage “a body in motion stays in motion” may not be too far off after all.
Within the joint, a substance called CS-846 (chondroitin-sulfate 846) has been measured in experiments to characterize what happens to the proteoglycan network during exercise and different stages of life.
Research has found that CS-846 is highest in fetal and newborn cartilage and gradually declines with age, indicating that proteoglycan synthesis is greatest in early development. CS-846 levels have also been shown to be elevated after joint injury or trauma, which also makes sense. Synthesis here indicates the joint’s effort to repair itself.
Interestingly enough, in horses, research has found that CS-846 levels increase with high-intensity exercise. This is probably due to excess stress on the joint (just like in joint injury or trauma) which pushes the cartilage’s repair mechanisms into overdrive as it attempts to mend itself as quickly as possible, as best it can.
This is not to say your horse can’t do high intensity exercise; rather, if you are using your horse in high intensity performance events, there’s stress going on in their joints. Period.
Luckily, there are simple ways to protect your horse’s joints. This is not a comprehensive list by any means, but it is a start:
1. Give your horse a sufficient warm-up and cool-down. Not only is this common sense, but light intensity work is important for strengthening the connective tissues within the joints, such as tendons and ligaments. Remember, exercise is ideal for joint health, but we want to make sure that it is not high-intensity, damage-causing exercise 100% of the time.
2. Pay attention to their feet. I’m sure you’ve heard the saying, “No hoof, no horse.” Keeping your horse’s feet trimmed at all the correct angles is HUGE for healthy joints, especially when it comes to concussion and force. Develop a good working relationship with your farrier and make sure your horse’s feet are properly cared for on a consistent schedule.
3. Be proactive. Joint wear and tear is inevitable, but that doesn't mean there aren't ways to slow down the aging process. Use high quality, research-backed supplements, such as Equithrive, which contains bioavailable joint supportive nutrients (meaning your horse will actually absorb the nutrients), such as chondroitin sulfate, glucosamine, hyaluronic acid and resveratrol.
There’s a lot of “hullabaloo” out there about equine joint supplements, but they are definitely not all created equally. My recommendation is to do your homework and choose the ones which have been scientifically validated.
What do you do to protect your horse’s joints?
