There are different forms of Inflammation, ranging from acute to chronic. Inflammation plays an important part in the immune response and is designed to help us survive – it is the immune system’s response to infections and injury.
The inflammatory response has helped us to survive in the evolutionary environment. Throughout evolution, the inflammatory response has stayed the same – our environment however, has changed drastically in the past couple of centuries (not a long time in evolutionary terms!).
The changes in our environment are thought to parallel the rise in chronic disease. Could inflammation be one of the reasons?
What Is Inflammation?
Inflammation is the response of the immune system to infection or injury. It is the mechanism used to protect us against infections (foreign invaders) and also to repair tissue damage such as injury.
There are two types of inflammation: acute and chronic.
Acute inflammation is characterized by the four signs of inflammation:
Other physiological changes can accompany inflammation such as:
- Loss of appetite
- Increased sensitivity to pain
The Four Signs of Inflammation
Heat can be fever or localized heat around damaged tissues (such as wounds).
Fever is produced by certain chemicals in the brain that trigger the hypothalamus to increase the body’s thermostat. Heat is one of the ways by which the body wards off infections.
Therefore, suppressing fever may not be a good idea and could allow infections to take hold.
Pain is a protective mechanism. As horrible as pain is, it is there for a reason.
When we touch something hot, for example, the acute pain makes us move away from the offending object immediately.
Chronic pain, on the other hand, is caused by chemicals released by the body. It is designed to make us keep the wounded area as still as possible and take extra care to protect the wounded area so that it can heal.
Swelling is caused by the leakage of blood plasma into tissues.
When the body is damaged, whether by injury or an infectious pathogen, cells break. When the cell wall ruptures, the contents of the cell spill out in the surrounding tissues.
When cells are damaged, nerves react by widening blood vessels to increase blood flow to the damaged area. This also contributes to swelling.
With increased blood flow, more nutrition and oxygen can be carried to the cells to aid recovery and also more immune cells that help fight off infections.
As you can see from the above, a level of inflammation is protective and necessary, but it should only last for a short period of time.
Chronic inflammation may persist for weeks, months or even years and is generally destructive.
Classically, inflammation is only diagnosed when all four signs of inflammation are present. Chronic low grade inflammation, however, is invisible.
When the inflammatory stimulus persists, pro-inflammatory chemicals keep on being secreted. Their normal job is to destroy cells that may be infected. However, if this is ongoing, healthy cells may be destroyed.
Continued release of pain-causing chemicals can lead to chronic pain.
Various inflammatory chemicals have been implicated in chronic disease such as autoimmune disease and cancer.
The Immune System
Inflammation is the most important part of the immune system. If the immune system dysfunctions, the immune response can become destructive to the host.
There are two different types of immunity: innate (non-specific) and acquired (specific) immunity.
Innate immunity is our first line of defence and we have it from birth. It includes the barriers that protect us from the outside world including: the skin, digestive tract and respiratory membranes. Innate immunity is not specific but mounts a generalized immune response to fight off pathogens until a more targeted response can take place. Inflammation is a key factor of the innate immune response.
Acquired immunity develops throughout life and is a targeted response carried out by immune cells (B-cells and T-cells) towards a specific invader. The memory of this invader (for example a virus) triggers this response. This is why if we had an infection (let’s say measles) in the past, we will not get this infections again.
With regards to T-cells, there are two different responses: Th1 and Th2. They are balanced by T-regulatory cells (T-reg). Keeping them in balance is important for a healthy immune response. An imbalance where Th1 becomes dominant is associated with autoimmune diseases (the body can’t distinguish its own tissue from a foreign invader and starts attacking it) and Th2 dominance is associated with allergies (the immune system over-reacts to a foreign particles). In both instances, low levels or inactivity of T-reg cells seems to be the issue.
What causes Chronic Inflammation?
Essentially, chronic inflammation is the result of a chronically activated and dysregulated immune system.
One of the reasons why this is common nowadays is that our environment has drastically changed from the environment in which the immune response evolved.
We could say there is a mismatch between our current environment and our genes.
The following factors can play a role in chronic inflammation:
- High simple carbohydrate consumption: Simple carbohydrates include refined sugar and processed flour and potato products – the staples of the modern diet. These have a high-glycaemic (GI) index (meaning they raise blood sugar quickly). High-GI diets have been shown to increase inflammation .
- Stress: When we encounter a stressor, the body releases ‘stress-hormones’. Long-term, these hormones can affect the production of T-cells and can reduce the output of the anti-inflammatory hormones DHEA.
- Sleep deprivation: Sleep is the time when the body restores itself. If it can’t do this due to limited sleep, destruction of cells may outweigh repair, potentially causing inflammation. Lack of sleep is also a stressor to the body.
- High Omega-6 Fat consumption: The essential fatty acids omega-3 and omega-6 are ‘raw materials’ for certain chemicals in the body. Omega-3 fats are turned into anti-inflammatory compounds, while omega-6 is the precursor to pro-inflammatory chemicals. We need both, but ideally the ratio should be 1:4 or some argue it even should be 1:1. Unfortunately we are much more likely to consume more omega 6 fats due to the rise of industrial seed oils in modern foods. Moreover, these fats are very susceptible to heat oxidation, turning them into sources of free-radicals.
- Free radicals: Free radicals are atoms, molecules or ions that have an unpaired electron and are therefore chemically unstable. Because they are highly reactive, they can cause damage in large numbers. Free radicals are produced by the body itself but can also be found in our environment for example in air pollution, burned foods, excessive sunlight exposure etc. The damage they cause can lead to inflammation.
- Chronic Infections: Chronic gut, viral or bladder infections could play a role in activating the immune response. This could include parasites, hidden viruses and an imbalance between good and bad bacteria and/or fungi.
- Toxins and Heavy Metals: Toxins and heavy metals are often similar enough to chemicals (such as hormones) and minerals in the body that they can replace them. This could have many consequences, one of which is inflammation.
- Nutrient excess or deficiency
Inflammation and Bladder conditions
Inflammation is probably a part of most chronic conditions. But as this blog focuses on bladder health, I’d like to take a closer look at these conditions.
It should come of no surprise for anyone suffering from IC that this is an inflammatory condition. The production of inflammatory chemicals called cytokines and chemokines in the bladder have been associated with IC and have been found to be raised significantly in IC patients, whilst certain anti-inflammatory chemicals were found to be lowered . Chemokines may play a role in lesions, potentially resulting in ulcers such as found in classic IC .
The inflammation can lead to ‘hyperexcitability’ of the bladder, resulting in pain and other symptoms.
These markers are indicative of chronic inflammation, whilst markers for acute inflammation have not been found to be higher in IC .
Overactive bladder patients have also been found to have higher inflammatory chemicals associated with chronic inflammation and not acute inflammation .
Levels or C-reactive protein (CRP), a marker for systemic inflammation in the body, have also been found to be raised in the blood of OAB patients .
Urinary Tract Infection
UTIs have been shown to have high levels of acute inflammation  – as would be expected in acute infections.
In next week’s article, I will share tips on how to test for and tackle chronic inflammation so make sure you check the blog!
What is your experience with inflammation? Let me know in the comments!
Pin it for later:
- Gökhan S. Hotamisligil Inflammation and metabolic disorders NATURE|Vol 444|14 December 2006|doi:10.1038/nature05485
- Egger, G. and Dixon, J. (2009), Should obesity be the main game? Or do we need an environmental makeover to combat the inflammatory and chronic disease epidemics?. Obesity Reviews, 10: 237–249. doi:10.1111/j.1467-789X.2008.00542.x http://onlinelibrary.wiley.com/doi/10.1111/j.1467-789X.2008.00542.x/full
- Pai C. Kao et al Serum C-Reactive Protein as a Marker for Wellness Assessment Ann Clin Lab Sci Spring 2006 vol. 36 no. 2 163-169 http://www.annclinlabsci.org/content/36/2/163.short
- Yoshimura, Naoki et al. “Bladder Afferent Hyperexcitability in Bladder Pain Syndrome/interstitial Cystitis.” International journal of urology : official journal of the Japanese Urological Association 21.0 1 (2014): 18–25. PMC. Web. 7 Oct. 2017. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089034/
- Ma, Emily et al. “A Multiplexed Analysis Approach Identifies New Association of Inflammatory Proteins in Patients with Overactive Bladder.” American Journal of Physiology – Renal Physiology 311.1 (2016): F28–F34. PMC. Web. 7 Oct. 2017. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4967156/