This post is the first in a series taken from the article by Keith Wassung entitled “Inflammation and the Healing Process”. This series focuses on Inflammation and the Healing process, Drugs & Inflammation, Central Nervous System & Inflammation and Inflammation and the Healing process: Conclusion. This week’s post looks at Inflammation and the Healing process.
The role of inflammation in the process of healing has been misunderstood for many years. Recent neurological and immunological research has shed light on its importance in the human healing process. A clear shift in science is taking inflammation away from being the enemy of health and a condition to be suppressed and or eliminated to one in which its importance and role is allowed to proceed.
Inflammation is one of the most important mechanisms of host defense since it marshals the attack on the injurious agent and leads to repair of the affected tissue.1
-The Cell Biology of Inflammation
Inflammation: Tissue Response to Injury
The inflammatory response is a natural defense mechanism that is triggered whenever body tissues are damaged in any way. Most of the body defense elements are located in the blood and inflammation is the means by which body defense cells and defense chemicals leave the blood and enter the tissue around the injured or infected site. Inflammation occurs in response to physical trauma, intense heat and irritating chemicals, as well as to infection by viruses and bacteria.
The inflammatory response:
- Prevents the spread of damaging agents to nearby tissues.
- Disposes of cell debris and pathogens.
- Sets the stage for the repair process.
The four cardinal signs of inflammation are redness, heat, swelling and pain. Many experts consider impairment of function to be the fifth cardinal sign of inflammation.
The inflammatory process begins with chemical “alarms” a series of inflammatory chemicals that are released in the extracellular fluid. Injured tissue cells, phagocytes, lymphocytes, mast cells and blood proteins are all sources of inflammatory mediators, the most important of which are histamine, kinins, prostaglandins, complement, and lymphokines.
Though some of these mediators have individual inflammatory roles as well, they all promote dilation of the small blood vessels in the vicinity of the injury.
As more blood flows into the area local hyperemia (congestion with blood) occurs which accounts for the redness and the heat of the inflamed area.
These chemicals also increase the permeability of local capillaries. Consequently, exudate, fluid containing proteins such as clotting factors and antibodies, seeps from the bloodstream into the tissue spaces.
This exudate is the cause of the local edema or swelling that in turn, presses on adjacent nerve endings, contributing to a sensation of pain. Pain also results from the release of bacterial toxins, lack of nutrition to the cells in the area, and the sensitizing effects of released prostaglandins and kinins. If the swollen and painful area is a joint, normal movement may be inhibited temporarily in order for proper healing and repair to occur.
Although at first, edema may seem to be detrimental to the body, it isn’t. The entry of protein-rich fluids into the tissue spaces.
- Helps to dilute harmful substances, which may be present.
- Brings in large quantities of oxygen and nutrients necessary for the repair process.
- Allows the entry of clotting proteins which form a gel-like fibrin mesh in the tissue space that effectively isolates the injured area and prevents the spread of bacteria and other harmful agents into the adjacent tissues. It also forms a scaffolding for permanent repair.
Benefits of Inflammation
Inflammation is often associated with the inflammatory response to tissue injury or trauma, but inflammation is at work in the body at a bio-molecular level on a constant, basis without any symptomology. Inflammation helps to maintain homeostasis in the body by coordinating immune function, including T cell mediation to identify and eliminate cancer cells.
T-Lymphocytes or T cells are involved in:
- Inflammatory reactions.
- Increasing the numbers of cells for a strong
defense of the body.
The destruction of cancer and infected cells.
T cells are one of the first immune cells to become aware of the presence of foreign cells. When they notice that an infection has occurred, they release different classes of immune cofactors or biochemical signals that activate B cells to produce antibodies and other immune cells. By using these messages, T cells recruit additional cells and start an immune reaction. Regulatory T cells defend the body by recruiting other cells. These cells “talk” to one another with immune cofactors, which are small bioactive signals that are produced by cells.
I would like to begin my consideration from the homotoxicological viewpoint by pointing out the effectively beneficial aspects of the inflammatory process. As a result of the effects of histamine, and in conjunction with permeability dysfunction’s, blood plasma with antigens extravasates from blood vessels. Connecting tissue, which lies between the blood vessels and parenchyma, subsequently produces a tissue gel in response to the following processes which act on it. The enrichment of acids and the diminution of oxygen which occur here, the production of hyaluronidase among the bacteria present, and the presence of toxic products of metabolism (so-called homotoxins). In this phase of inflammation, leukocytic cells are produced in the manner, which has been very impressively demonstrated in the well-known experiment by Busse-Grawitz. Now, at this point, the toxic products of metabolism can, together with the pus formed, be properly eliminated from the organism, in the sense of a biologically effective detoxification reaction. Any measure taken to impede this process of detoxification signifies a corresponding hindrance of the process of healing. 3
No one could survive without precise signaling in cells. The body functions properly only because the cells constantly communicate with each other.2
Basic studies shed light on immune function
Immunologists at Oregon State University have recently uncovered some important clues as to how the immune system works at a fundamental level. The key, scientists say, is understanding how some of the T cells, which are sort of the quarterback of the immune system that directs other cells to go do their dirty work, can get stimulated to do their work even better, or tone it down in the case of an autoimmune condition. One of the things that has intrigued scientists is the apparent correlation between inflammation and a dysfunctional immune response, especially with autoimmune diseases. Steroid treatments, for instance, which have strong anti-inflammatory effects, are often used to treat autoimmune disorders.
“But using a powerful steroid drug, which can have many side effects, to indirectly affect something as delicate as the immune system is like hitting an ant with a sledgehammer”, according to Anthony Vella, an assistant professor of microbiology at OSU. “What we have tried to identify is exactly how the process of inflammation is related to immune function and what cellular processes are involved.” In one recent breakthrough, the OSU research program determined that inflammation in conjunction with the activation of other T cell stimulatory molecules can help T cell growth and increase the number of “fighting” T cells. In experiments, OSU researchers showed that injecting mice with an antigen caused significant death of the antigen-responsive T cells; however, when inflammation was present, it prevented the death of these cells. In cell membranes of certain bacteria, there is a natural bacterial lipid called lipopolysaccharide, or LPS. It appears that LPS can play a role in causing inflammation, and keeping activated T cells alive.4
Oregon State University Immunology Research Department
When one considers that in wound healing there is cell and tissue proliferation proceeding at a rate exceeding that seen in malignant tumors, it is humiliating to admit how little we know of the mechanisms involved. It is evident that our knowledge of healing is woefully deficient. We understand neither the signal that starts the process of healing nor the mechanisms that control and maintain it. Failure to identify the mechanism by which normal tissue homeostasis is maintained is particularly disappointing since any understanding of the major disorders of cell division ( cancer ) must be related to a knowledge of the normal controlling mechanisms of cell growth.5
Principles of Disease
When you see the letters itis at the end of a word, it means “inflammation of” The first part of the word indicates the part of the body that is involved in the inflammation process. For example, the word dermatitis means inflammation of the skin (derm) and arthritis is the inflammation of a joint in the body. It most cases the term itis at the end of a word denotes a chronic condition.
Chronic inflammation is an inflammatory response of prolonged duration–weeks, months, or even indefinitely, who extended time course is caused by persistence of the causative stimulus to inflammation in the tissue, repetitive use of anti-inflammatory drugs, a weakened immune system, or improper nerve supply.
Chronic inflammation inevitably causes tissue damage and is accompanied by simultaneous attempts at healing and repair. The exact nature, extent and time course of chronic inflammation is variable and depends on the balance between the causative agent and the attempts of the body to remove it.
1. Walters, L. The Cell Biology of Inflammation. p.138WB Saunders and Co, Philadelphia.
2. Scott, J. & Dawson, T. “Cell communication: The inside story” Scientific American, June 2000. p. 73.
3. Biological Therapy, Vol. VIII, No. 4, October 1990, p. 85-88.
4. Vella, A. “Basic studies shed light on immune function” Oregon State University, 12-17-1998
5. Walter, J. MD Principles of Disease, 2nd edition p.105 WB Saunders and Co. Philadelphia.