Inflammation, especially in rheumatoid and arthritis conditions, is an ongoing problem in today’s society. When the word is mentioned, we often think of the 5 cardinal signs which include pain, redness, heat, swelling and loss of function, however we need to realize that in the case of chronic diseases, this is not always the scenario. Inflammation is broken up into two main categories; acute and chronic. In most instances, those typical signs are associated with acute inflammation, but for purposes of our discussion, we will be focusing more on the insidious or chronic inflammation and the impact on joint degeneration, arthritis, and pain.
Acute inflammation is part of the body’s natural defense mechanisms, often responding to a localized infection, foreign body or trauma. The end results is alteration of the blood circulation, recruitment of white blood cells and release of many inflammatory proteins with the intention of providing healing and removal of invading organisms. It is a good thing for the short term, but problems develop when the condition continues.
Chronic inflammation is often referred to as a ‘smoldering fire‘ in the background of life and a direct cause of our aging process and natural tissue degeneration. It is a fact of life, but is often worsened by many contributing factors including lifestyle, diet, body condition, stressors, genetics and environmental influences. Ongoing inflammation has been shown in research to actually increase the incidence and progression of many diseases including cardiovascular, neurodegenerative, pulmonary, allergic type conditions, immune mediated, cancer, and even joint degeneration.
Arthritis implies inflammation of a synovial structure, which includes the joint, with the most common form being osteoarthritis (OA). This condition impacts people, pets and horses and is often attributed to trauma to a joint, overuse or strain, localized infection (septic arthritis) or a natural sequela to aging. In the case of Rheumatoid Arthritis (RA), the body’s own immune system begins to attack the tissues comprising the joint, including the joint capsule and cartilage, leading to pain, degeneration and debilitation. In both cases, the disease can impact the joint capsule, periarticular structures, joint cartilage and even the bone underlying the cartilage (subchondral bone). In many instances, the condition starts often in the soft tissue such as the joint capsule and surrounding supportive structures, then with time, moves more inward involving the deeper structures. Typical diagnostic tests including x-rays or radiographs only detect or reveal bone or cartilage degeneration, but we have to remember that often the problem is just within the soft tissue structures, which does not appear on the x-ray film.
In today’s current medical and veterinary fields, there are no medications available that can reverse or restore function to damaged tissues in any form of arthritis, thus the importance of understanding the impact of inflammation might help to give us opportunities to manage the condition better and potentially slow progression.
Osteoarthritis is one of the most debilitating conditions affecting people with millions impacted each year. The most common clinical signs associated with OA are pain, heat, swelling and reduced mobility. In severe cases, due to bone remodeling, there may actually be an obvious outward change to the joint with enlargement or even deviation of the associated bones in terms of angulation, again due to degeneration, which then also contributes to decreased mobility. The condition is more common as we age, but is also prevalent in those individuals and animals with excessive wear and tear, due to work conditions, training or high level competition.
Rheumatoid arthritis is thought to impact up to 1% of the adult population, again associated with a high level of disability, pain and degeneration. The condition is connected with an improper immune response, resulting in an attack upon the joint tissues and cartilage, however, it is systemic in origin and can actually manifest elsewhere in the body including various organs. Individuals with RA have been shown to have an increased incidence of other conditions including cardiovascular disease and even certain types of cancer. There is a higher proportion of women impacted by RA than men, with the general onset between the ages of 40 and 60. In some studies, there appears to be a possible connection with various hormones as there is a higher incidence around the menopausal age and the juvenile form appears often around puberty.
The Role of Inflammation in Osteoarthritis and Rheumatoid Arthritis
Inflammation is closely tied into joint degeneration in both conditions, not only resulting in elevated pain levels, but being directly responsible for cartilage erosion through the increased production of various inflammatory proteins and enzymes. This process results in proteoglycan depletion, which then weakens the cartilage and surrounding matrix. The inflammatory process involves numerous proteins, enzymes and cytokines, all playing a pivotal role in tissue degeneration. Ongoing inflammation can also impact and alter immune function, which may actually then contribute to an increased incidence of immune mediated conditions such as RA.
The interesting thing regarding many of these inflammatory cytokines is that many of them are regulated in their production by one transcription factor called NF-kB. This transcription factor is present within the cytoplasm of various immune cells and often ‘set off’ or activated in many conditions including RA and OA. When the transcription factor is active, genetic translation results in the production of many inflammatory proteins, which then contribute to the ongoing events not only in RA and OA, but many other chronic diseases.
Inflammation is a fact of life, but we have to come to the understanding that many things within our lives contribute to the problem and accelerate the progression. Given that our current medical therapies and pharmaceutical options offer little hope in terms of reversing or restoring function fully, the goal should be to understand and intervene at the level of inflammation, hoping to gain better control, slowing the progress and improving quality of life. Considering that inflammation is a natural sequelae to aging and induced by many factors, we can also realize that earlier intervention could lead to better outcomes.
In the next article, we will be discussing current therapies, which will include alternative options.
All our best,
Tom Schell, D.V.M., CVCH, CHN
Nouvelle Research, Inc.