What Drives Arthritis?

The “wear and tear” model of arthritis never really sat well with me. It just doesn’t make much sense if you understand physiology. It’s common for healthcare professionals to make analogies of the body being like a car. This can make sense in some ways such as fuel and metabolism. However, the problem is that many people, including healthcare professionals, say things such as, “like a car, your parts just wear out”. That reminds me of the quote, “just because it’s logical, doesn’t mean it’s physiologic”. 

The idea is that if you are obese, you are going to put more mechanical pressure on your joints and wear them out faster. Certainly, there is a correlation between obesity and arthritis, but I don’t think pressure is the main driver. There is a law in physiology called Wolff’s law: Bone grows and remodels in response to the mechanical stresses placed upon it. That’s for all tissues too, not just bone, including cartilage. So you’d expect that pressure would grow cartilage, not erode it. We’ve seen studies that show that runners have more knee cartilage than sedentary people. So it doesn’t quite add up. 

It also doesn’t make sense that those with obesity have more arthritis in the hands, which are non-weight bearing. Also, it is well known that astronauts come back from space with cartilage erosion and osteopenia, or bone loss. They are in a weightless environment, how does this make sense? This goes back to Wolff’s law that can be rephrased to: Bone breaks down in response to the mechanical stresses not placed upon it.

So what is the driver? Researchers have discovered that body fat plays an important role in joint health, because of the hormones fat tissue produces. One of the most important of these hormones is called leptin.

Leptin is best known as the hormone that tells the brain when we have enough energy stored. In theory, higher levels of leptin should make us feel full and encourage us to use energy. In practice, many people develop what is called leptin resistance, where the brain no longer responds properly. This is one reason why obesity is often difficult to overcome.

What makes leptin even more interesting is that it is found inside the fluid that cushions our joints. Cartilage cells and other tissues in the joint can also produce it. Instead of protecting the joint, leptin often promotes inflammation and activates enzymes that break down cartilage. It can also influence bone, encouraging the growth of bony spurs known as osteophytes that are a hallmark of osteoarthritis. Higher leptin levels act almost like a chemical messenger that speeds up joint damage, even in joints that do not carry much weight, such as the hands.

I’m not suggesting this is the only driver, but certainly a key driver. We know of other contributors such as pathogenic gut bacteria. We find the same gut bacteria in arthritic joints and they inhibit the turnover of new cartilage. We also know there is a strong correlation between excess sugar in the diet and arthritis. 

The reason that I think this is an important point is because it changes the prescription. Patients with arthritis are commonly told to rest and protect the joints. Perhaps that’s the worst possible thing to do. 

References:

Dumond H, Presle N, Terlain B, et al. "Evidence for a key role of leptin in osteoarthritis." Arthritis Rheum. 2003;48(11):3118–3129.

Francisco V, Pérez T, Pino J, López V, Franco E, Blanco FJ, et al. "Biological role of adipokines in osteoarthritis: a systematic review." Int J Mol Sci. 2019;20(18):4650.

Gandhi R, Takahashi M, Smith H, Rizek R, Mahomed NN. "The synovial fluid adipokine network in osteoarthritis." Arthritis Rheum. 2011;63(3):719–727.

Ku JH, Lee CK, Joo BS, An BM, Choi SH, Wang TH, Cho HL. "Correlation of synovial fluid leptin concentrations with the severity of osteoarthritis." Clin Rheumatol. 2009;28(12):1431–1435.

Mosher TJ, Liu Y, Torok CM. "Functional cartilage MRI T2 mapping: evaluating the effect of physical activity on knee cartilage." Osteoarthritis and Cartilage. 2010;18(3):358–364.

Tirman PF, Feller J, Janzen DL, Peterfy CG, Bergman AG, Mosher TJ, Genant HK. "MRI of articular cartilage in the knee: correlation with physical activity." AJR Am J Roentgenol. 1997;169(1):111–118.

Understanding the Connection Between Arthritis and Gut Dysbiosis: Exploring the Gut-Joint Axis

Arthritis, a condition characterized by inflammation and stiffness in the joints, affects millions of people worldwide, causing pain and reduced mobility. While it's traditionally been viewed as a joint-specific issue, emerging research is shedding light on the intricate connection between arthritis and gut health. In particular, the concept of gut dysbiosis, an imbalance in the gut microbiota, is gaining attention for its potential role in exacerbating arthritis symptoms and even contributing to its development.

The Gut Microbiota: A Key Player in Health

The gut microbiota, consisting of trillions of microorganisms residing in our gastrointestinal tract, plays a crucial role in various aspects of our health, from digestion and nutrient absorption to immune system regulation and beyond. A diverse and balanced gut microbiome is essential for maintaining overall well-being. 

Arthritis encompasses a range of conditions, including osteoarthritis, rheumatoid arthritis, and psoriatic arthritis, each with its unique characteristics and underlying causes. While joint inflammation is the hallmark feature of arthritis, it's increasingly recognized as a systemic condition that can affect multiple organs and systems in the body.

The Gut-Joint Axis: Unraveling the Link

There appears to be a bidirectional relationship between the gut and joints, known as the gut-joint axis. This means that gut dysbiosis can influence the development and progression of arthritis, while arthritis can, in turn, impact gut integrity and microbial balance. It was long thought that being obese causes too much wear and tear on the joints. Well we now know that fat cells secrete inflammatory cytokines. So fat cells are in a sense, an endocrine organ. 

Gut dysbiosis refers to an imbalance in the composition and function of the gut microbiota, often characterized by a reduction in beneficial bacteria and an overgrowth of harmful microbes. Diet, medications, stress, and environmental toxins can disrupt the delicate balance of the gut microbiome, leading to dysbiosis. Joints that are arthritic have the same pathologic bacteria in them that the gut does. It’s thought that these bacteria inhibit the action of the progenitor cells, the ones that replace cartilage. 

Several mechanisms have been proposed to explain how gut dysbiosis may contribute to arthritis. These include:

1. Immune Dysregulation: The gut microbiota plays a crucial role in educating the immune system and maintaining immune homeostasis. Dysbiosis can trigger an inappropriate immune response, leading to systemic inflammation that exacerbates joint inflammation in arthritis.

2. Intestinal Permeability: Dysbiosis-induced damage to the intestinal lining, known as increased intestinal permeability or "leaky gut," allows harmful substances such as bacterial toxins and undigested food particles to enter the bloodstream, triggering immune reactions and promoting inflammation throughout the body, including the joints.

3. Metabolic Dysfunction: Dysbiosis can alter the metabolism of dietary components and produce metabolites that influence inflammation and oxidative stress, both of which are implicated in the pathogenesis of arthritis.

4. Molecular Mimicry: Dysbiosis may promote the production of microbial antigens that resemble host tissues, leading to cross-reactive immune responses that mistakenly target joint tissues, contributing to autoimmune forms of arthritis such as rheumatoid arthritis.

Managing Arthritis Through Gut Health

Optimizing gut health may offer a promising approach for managing arthritis symptoms and slowing disease progression. Strategies to support gut health include:

1. Probiotics and Prebiotics: Consuming probiotic-rich foods (such as yogurt, kefir, and fermented vegetables) and prebiotic fibers (found in fruits, vegetables, and whole grains) can help restore microbial balance and promote a healthy gut environment.

2. Dietary Modifications: Adopting an anti-inflammatory diet rich in fruits, vegetables, healthy fats, and animal proteins while minimizing processed foods, sugar, and polyunsaturated fats can reduce inflammation and support gut health.

3. Stress Management: Exercise has a well established role in reducing stress. Practicing stress-reduction techniques such as meditation, yoga, and deep breathing exercises can help modulate the gut-brain axis and improve gut function. Cold plunges are another quick way to reduce stress. 

4. Supplements: Certain supplements, such as omega-3 fatty acids, vitamin D, and butyrate, may have beneficial effects on gut health and inflammation in arthritis.

To read some research articles on this topic, see below:

If you want help restoring your gut microbiome, let’s get on a free consult call: