Home › Blog › Protein Released by Fat Cells Higher in Those with Arthritis

We’ve known for a long time that there was more going on than the extra wear and tear caused by extra weight in arthritis. Metabolic syndrome, a situation that can result from high-sugar and carbohydrate diets, lack of exercise, stress, lack of sleep, and sometimes genetics is also a huge factor in the breakdown of joints as well as many other serious health risks. What does the fat stem cell secreted protein called adiponectin have to do with this? Let take a look…

A Quick Review of Osteoarthritis

Osteoarthritis is a degenerative disease that affects not just the joint-protecting cartilage but can also be associated with pain, stiffness, and bone issues, such as bone spurs that form to address instability or bone marrow lesions (BMLs) that occur in the subchondral (beneath the cartilage) bone, particularly common in hip arthritis. It’s also interesting to note that arthritis can really present as an entirely different disease depending on the joint involved. For example, knee arthritis and hip arthritis are much different diseases based on a variety of things, such as speed of progression, formation of bone cysts, ability of the joint to self-maintain, and so on (if you want to learn more about this, watch my short video below).

While arthritis can be genetic, there are often external factors at play in arthritis as well, such as obesity, previous injuries, and so on. Osteoarthritis is also the number-one reason why patients undergo joint replacements!

Now, a new study suggests that the protein adiponectin may be one indicator of arthritis.

What Is Adiponectin?

Adiponectin is the most abundant protein secreted into our blood serum by our fat (adipose) cells, specifically those in our white fat tissue. Previous studies have shown benefits to the adiponectin protein in the blood, such as a decreased risk of atherosclerosis and heart attack as well as a reversal of insulin resistance and type-2 diabetes. Low adiponectin levels, it has recently been suggested, may actually be an indicator of metabolic disease. So normal levels of adiponectin seem to be a good thing. Unfortunately, however, our understanding of the fat arthritis connection just became clearer as there seems to be a very fine balance here as excess concentrations of adiponectin in the blood may come with a sacrifice—our joints. Let me explain.

The Fat Arthritis Connection: Arthritis Patients Found to Have High Concentrations of Adiponectin

According to today’s focus study, previous studies have made a variety of conflicting associations between adiponectin and osteoarthritis. For example, in one, increased inflammatory markers (e.g., interleukin 6) were found when cartilage cells were treated with adiponectin (suggesting eventual cartilage breakdown and arthritis). In another, excess amounts of adiponectin were found in the synovial fluid (the fluid that lubricates the joints). In yet another, no association was made between adiponectin and arthritis, while another found a benefit to joints with increased concentrations of adiponectin.

All of these conflicting findings regarding the fat arthritis connection motivated researchers to complete a new study using a meta-analysis (an aggregate of many studies) of thirteen studies to investigate whether or not an actual association existed between adiponectin and arthritis. The final result? Adiponectin levels were found to be higher in those with arthritis than in those without, leading researchers to conclude that there may indeed be an association between those high adiponectin concentrations and the occurrence of arthritis. These findings were especially pronounced in late-stage arthritis and in knee arthritis.

Other Connections with Osteoarthritis

Adiponectin is only one of many potential connections to arthritis. Take a look at a few other associations that have recently be found:

• One study found that cardiovascular disease may be linked to osteoarthritis via a compound called acylcarnitines that is produced when lipid is metabolized.
• Unfolded proteins may be a catalyst not just for arthritis but also metabolic syndrome and the creation of bad stem cells.
• Hypertension may increase the risk of knee arthritis.
• Drinking five beers (or more) per week may double the risk of knee or hip arthritis.

The upshot? What do these new fat arthritis connection findings mean? We’ll see what the future holds, and whether they may factor into early diagnosis or be a target for treatment. What we do know is the causes of arthritis are many. Some of which are genetic, some of which can be controlled by lifestyle choices, and some by treatment. Do what you can on your end, and we’re here to help on the treatment end!

Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile