Aspirin, COX-2 and Inflammation

When aspirin was first created it was hailed as a wonder drug for inflammation, pain and fever. Aspirin relieves inflammation due to its ability to inhibit an enzyme in the body called COX-2. Unfortunately, aspirin also inhibits the COX-1 enzyme. This inhibition can lead to stomach irritation and bleeding problems.

Aspirin is chemically related to salicin, a chemical found in the inner bark of willow trees and also in some other plants. Willow bark has been used to treat pain and fever since ancient times. Salicin is turned into salicylic acid in our digestive tracts.

In the 1800’s scientists isolated salicin from willow and made salicylic acid, which was used as a medicine. However, the salicylic acid often caused severe stomach pain. German chemist Felix Hoffman, who worked for the Bayer company, is credited with the creation of aspirin in 1897. He converted salicylic acid into acetylsalicylic acid, also known as ASA or aspirin. Aspirin was found to cause less stomach pain than salicylic acid.

Inflammation is a normal body response to injury. When tissue is damaged by an infection, chemicals, physical trauma, heat or radiation, inflammation begins. Extra blood flows to the injured area, causing fluid to leak out of the blood vessels, resulting in heat, redness, swelling and pain. The blood and fluids contain white blood cells and proteins that destroy infectious organisms, such as bacteria and viruses. Inflammation helps to seal off the injured area from the rest of the body. In addition, damaged cells are destroyed and the repair of injured tissues begins.

Inflammation is uncomfortable but is normally a temporary process. This short-lived inflammatory response is known as acute inflammation. Acute inflammation subsides as pathogens are killed and body tissue is repaired. However, acute inflammation in certain parts of the body, such as in the brain, is very dangerous. Inflammation that lasts a long time (chronic inflammation) can lead to a variety of health problems.

There are several versions of the COX (cyclooxygenase) enzyme. The best known forms of the enzyme are COX-1 and COX-2. COX-1 is found in most of our cells. COX-2 is much less common, but is found in increased amounts in inflamed areas.

The COX enzymes stimulate the body to make chemicals called prostaglandins. Different prostaglandins produce different effects. Some maintain normal body function, but others cause inflammation, pain and fever. COX-2 stimulates the production of inflammatory prostaglandins. Aspirin inhibits the manufacture of COX-2, thereby decreasing inflammation.

Aspirin inhibits the COX-1 enzyme as well as the COX-2 enzyme. COX-1 stimulates the production of prostaglandins that maintain the mucus lining inside the stomach. This mucus lining protects the inner layer of the stomach from being attacked by the hydrochloric acid and digestive enzymes that are present in the stomach cavity. Without enough mucus in the stomach, a person taking aspirin may develop an inflamed stomach lining (gastritis) and ulcers (sores). Aspirin may also cause kidney problems, since COX-1 is needed for normal kidney function.

COX-1 also causes blood platelets to make thromboxane A2. This chemical triggers platelets to stick together around a wound, starting the clotting process. Since aspirin inhibits the production of COX-1, it also inhibits blood clotting. Wounds on the stomach wall and elsewhere may bleed more freely during treatment with aspirin.

In addition, up to twenty percent of adults with asthma may experience an asthma attack when they take aspirin. Aspirin can also cause tinnitus (ringing or other sounds in the ears in the absence of external sounds), or make existing tinnitus worse. In children with a viral disease, aspirin use may cause Reye’s syndrome, a very dangerous condition in which the brain and liver swell.

Aspirin’s ability to reduce blood clotting may be helpful in some people, such as those at risk for developing blood clots in the heart, resulting in a heart attack, or blood clots in the carotid arteries traveling up the neck to the brain, which could lead to a stroke. Some doctors recommend that patients who have an increased likelihood of developing these disorders take a low dose of aspirin every day.

NSAID’s (Non-Steroidal Anti-Inflammatory Drugs) are a group of chemicals that include aspirin and ibuprofen. Like aspirin, ibuprofen inhibits both COX-1 and COX-2. Acetaminophen is not a NSAID. It is used to treat pain and fever, but unlike aspirin and ibuprofen, it only weakly inhibits the COX-2 enzyme and is not anti-inflammatory. Acetaminophen is believed to exert its effects by acting on the central nervous system.

New drugs have been created that inhibit COX-2 but not COX-1. These drugs don’t create stomach problems since they don’t inhibit the COX-1 enzyme. Unfortunately, some of them have been found to cause serious health problems, including an increased risk of heart attack, stroke and liver damage, and have been withdrawn from the market.

Over the long-term, an anti-inflammatory diet can help chronic inflammation and reduce the need for anti-inflammatory medications. In an anti-inflammatory diet foods known to increase inflammation must be avoided, or at least limited. These foods include saturated fats, refined grains, sugar and alcohol. Artificial trans fats and hydrogenated fats should be eliminated from the diet.

Fats containing omega-3 fatty acids have been shown to reduce inflammation. Oily fish such as salmon and sardines are good sources of omega-3 fats. Extra virgin olive oil contains oleocanthal, which produces a stinging sensation in the throat just like ibuprofen does and also lowers the levels of COX-1 and COX-2 just like ibuprofen, reducing inflammation. The amount of olive oil that is normally ingested each day is equivalent to a weak dose of ibuprofen, but it’s believed that over time the regular consumption of extra virgin olive oil can decrease inflammation. Other substances that have been shown to reduce inflammation are green vegetables, berries, herbs and certain spices, especially ginger and turmeric.

Chronic inflammation contributes to many health problems. Some of these problems include rheumatoid arthritis, asthma and inflammatory bowel disease. If you have a disorder that involves inflammation, it’s certainly worth following an anti-inflammatory diet. This diet is healthy for everyone, whether or not a person is experiencing inflammation. Following the diet may enable you to reduce or even eliminate medications and their side effects.

DO NOT start taking daily aspirin to help prevent cancer without consulting your doctor. There are unpleasant and potentially dangerous side effects of aspirin use in some people, and as the video states, people with certain medical conditions should not take aspirin, and there are drugs that should not be combined with aspirin.

The video also points out you shouldn’t expect aspirin to stop you from getting cancer if you still perform activities known to promote the disease, such as smoking. Follow an anti-cancer diet and lifestyle before you even consider asking your doctor about using aspirin.

Although the results of the study described in the video are very interesting, remember that it was only one study. It will be interesting to see if other researchers confirm the results, and if they do, to discover whether aspirin interferes with cancer by reducing inflammation or by some other mechanism.