Health Diagrams III — Inflammation from Cell to Tissue

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I have explained my perspective in diagrams of the relationship between diet, gut flora and disease:

Health Diagrams I — Gut Flora and Diet

and of the interaction between gut flora, the immune system and autoimmunity:

Health Diagrams II — Curing Autoimmunity and Allergies

Now I am discussing how inflammation, the foundation of most chronic diseases, begins at the cellular level and results in the classic symptoms of tissue inflammation: redness, heat, swelling and pain.

NF-kB is the Transcription Factor that Controls Inflammation Genes

Of the 23,000 human genes, about 1,000 on each of 23 chromosomes, five dozen, e.g. enzymes involved in nitric oxide (vasodilation and erection hormone), synthesis of heparin sulfate and prostaglandin synthesis from omega-6 fatty acids or cytokines (IL-1, IL-6, TNFa), are associated with inflammation.  These inflammatory genes are turned on or expressed in individual cells, when the inflammation transcription factor, NF-kB, is activated by any of numerous external signals, including inflammatory cytokines, bacterial or fungal cell wall materials (LPS or beta-glucan), advanced glycation end products (AGE, e.g. HgA1C, resulting from high blood sugar) or reactive oxygen species (ROS, e.g. super oxide, from insulin resistance).

NF-kB and Inflammation
Superoxid Causes Insulin Resistance

Inflammation is the Foundation of Growth, Birth, Cancer and Pain

We think of inflammation as the sum of physical symptoms, and our purpose in responding to inflammation is typically to limit its impact.  We try to stop swelling by applying cold or hot, and we take aspirin to lower fevers and stop pain.  We fail to realize that inflammation is essential to the growth and development of many different tissues, and that inflammation is a cycle that leads back to normal function.  

Body tissues, such as the lining of the intestines or the uterus, continually produce new cells to replace the old that are sloughed off.  NF-kB must be turned on for these growth and attrition cycles.  Taking aspirin blocks NF-kB in the gut and stops local development of the lining, resulting in weak areas that bleed.  That is why doctors encourage patients to drink a half glass of water before and after swallowing aspirin tablets. 

Another more dramatic example of control of inflammation is conception, gestation and birth.  Conception and gestation require inhibition of inflammation, to permit growth of a foreign organism (a fetus is half sperm genes) in the uterus.  Chronic inflammation limits the ability of the uterus to suppress immune attack and can produce infertility, which is treated by aspirin and heparin, which suppress chronic inflammation.  The return of inflammation at the end of gestation precipitates labor and birth.  Excess Inflammation produces high levels of circulating inflammatory cytokines, which causes postpartum depression.  Depression and chronic inflammation have the same cytokine profiles, i.e. depression is a symptom of chronic inflammation.

Birth and Inflammation

Proliferation, or enhanced cell division, is another aspect of inflammation and is also the foundation for cancer.  That is the reason that some doctors recommend low dose aspirin to reduce colon cancer.  Similarly, since inflammation is the basis for coronary artery disease, doctors sometimes recommend low dose aspirin, although this is controversial.  Doctors also use aspirin as a so called blood thinner, since it blocks inflammatory signaling in platelets and discourages clotting.  Inflammation of nerve cells is experienced by the brain as pain.  

When it is understood that inflammation is an essential feature of many normal, healthy cell and tissue functions, then “inflammation," with its negative connotations, becomes a misnomer.

NSAIDs Inhibit Inflammatory Prostaglandin Production

Aspirin directly inhibits NF-kB activation inside the cell, but it also chemically modifies COX, the enzyme that converts omega-6 polyunsaturated fatty acids (common in polyunsaturated vegetable oils) into inflammatory prostaglandins.  Other NSAIDS (Non-Steroidal Anti-Inflammatory Drugs) just inhibit COX, but Aspirin transfers its acetyl group to make acetyl-COX, which has a new activity that converts omega-6 fatty acids into anti-inflammatory prostaglandins.  The high omega-6 fatty acid content of vegetable/seed oils, such as corn, soy, canola, etc. is why these oils, in contrast to olive oil or butter, are inflammatory.  Omega-3 fish oil is anti-inflammatory, because it is converted to anti-inflammatory prostaglandins.  Plant omega-3 fatty acids are shorter and are not converted to prostaglandins, but inhibit omega-6 conversion.

Aspirin

Nitric Oxide, Vasodilation and Viagra

Swelling is caused by vasodilation, the relaxation of blood vessels, and accumulation of serum in the tissue.  This vasodilation also makes the tissue red and warm from the increased amount of warm blood in the capillaries.  Vasodilation is caused by nitric oxide, NO, that is produced by an enzyme under the control of NF-kB, which takes the nitrogen from arginine (or nitroglycerine).  The NO diffuses easily and binds to receptors that produce an amplified signal, cyclic GMP, that relaxes the muscle cells surrounding blood vessels.  [Viagra is potentially dangerous, because it just exaggerates the amplified signal and obscures the underlying vascular damage, e.g. hypertension, that causes erectile dysfunction by blocking normal vasodilation.]

Nitric Oxide and Erectile Dysfunction

Hot/Cold and Endorphins

The dilemma of whether to use hot or cold therapy to block inflammation is based on a misunderstanding of what the temperature changes are actually doing.  Changing the temperature of the skin alters the structure of sensory proteins in nerves of the skin and triggers signals to the brain that register as hot or cold.  Chemicals, e.g. capsaicin or menthol, can have the same effect without changing skin temperature.  The important response for inflammation control, is return signals from the brain that release neurohormones, e.g. endorphins, from different nerves that reach not only some of the skin that was hot or cold, but also deeper tissue.  The endorphins block inflammation and all of its symptoms.  That is why chemically treated pads are more effective than icing or changing from hot to cold, because "hot" and "cold" signaling chemicals can be applied simultaneously.  None of the treatments is more than skin deep.  Actually chilling or heating tissue below the skin is damaging and causes more inflammation.  Low dose Naltrexone may be effective in some cases of chronic inflammation, by stimulating systemic rebound endorphin production.

Dr. Oz, Pain, Hot/Cold Receptors

Lymphocyte Offloading, Mast Cells, Heparin

Rosacea is a group of diseases that involve inflammation of the face in an exaggerated blush.  Any of the signals that would lead to blushing cause intense vasodilation.  A blush is fleeting, but rosacea is made chronic by another aspect of inflammation, offloading of lymphocytes.  Large numbers of lymphocytes accumulating in response to a local infection would produce pus.  In the case of rosacea, the distributed leucocytes, including neutrophils, respond to the blushing signals by producing inflammatory signals, such as P protein.  The result is cycles of inflammation, autoinflammation.

Mast cells can also be offloaded from blood vessels and provide a link between the immune system and inflammation.  Mast cells display IgE receptors on their surfaces, which bind antigens and trigger release of histamine, heparin and protease.  Histamine is a neurotransmitter that binds to receptors on blood vessels and nerve cells.  In the gut, histamine mediates many digestive processes.  Heparin released along with  histamine, coats the gut and prevents attachment of pathogens by competing for binding to the heparan sulfate proteoglycans (HSPGs) that form the surface of cells that line the gut.  [Heparin is the most common drug used in hospitals and is produced from intestines of cattle and hogs in the meat industry.]  Heparin also binds and inactivates the proteases released from mast cells.  Upon release, the now active proteases attack and activate receptors on nerves and immune cells.

Mast Cells and Heparin

Heparin is Anti-Inflammatory

Heparin is the most negatively charged polysaccharide, mediates most of the receptor/hormone interactions at cell surfaces; facilitates amyloid plaque formation, e.g. in Alzheimer's, atherosclerosis, diabetes, dementia; and controls numerous protease reactions in the complement system and clotting, etc.  There are hundreds of heparin-binding proteins.  Heparin is produced in secretory granules of mast cells by the action of heparanase on heparan sulfate proteoglycans. Heparin is a mixture of small fragments, oligosaccharides of heparan sulfate polysaccharides.  Heparin is anti-inflammatory and is administered to facilitate conception and gestation.  Inflammation also inhibits the genes involved in heparan sulfate proteoglycan production and since HSPGs are a major component of basement membranes of tissues and provide the barrier function of blood vessels in kidneys and brain, inflammation leads to proteinuria and loss of the blood brain barrier.  Since HSPGs have a short half life of six hours and are rapidly recycled, heparin added to the blood is rapidly absorbed by vessels, and heparin taken orally is absorbed by intestinal cells, but does not reach the blood.  HSPGs and heparin are central components of immunity and inflammation.

Heparin and Inflammation

Inflammation Blocks Skin Synthesis of Vitamin D from Cholesterol

Inflammation blocks solar synthesis of vitamin D in the skin and is more important than skin pigmentation, use of sunblock or latitude in producing vitamin D deficiency.  The vitamin D content of food is negligible compared to solar production in the skin.  It is not surprising that rising chronic inflammation is also accompanied by rising vitamin D deficiency.  Vitamin D supplementation is usually ineffective in curing vitamin D deficiency, because the supplements are too low and very high levels of supplemental vitamin D are required to reverse underlying chronic inflammation.  Statins are very effective at blocking cholesterol synthesis and although reducing cholesterol has minimal impact on the target, cardiovascular disease, it dramatically reduces vitamin D causing muscle pain, etc.

Most vitamins are enzyme cofactors synthesized by gut bacteria and used as quorum sensing signals during formation of biofilms.  Vitamin D, in contrast, is a steroid hormone and receptors for vitamin D are inside cells.  The receptor/vitamin D complex is transported into the nucleus where it acts as a transcription factor to control the expression of genes.  Vitamin D controls the expression of defensins in the crypts of the villi of the small intestines.  The antimicrobial activity of defensins is based on the basic amino acids (arginine and lysine) of its heparin binding domains.  Vitamin D also interacts with NF-kB in the nucleus and modulates inflammation.

Inflammation and Vitamin D

Bacteria and LPS

Lipopolysaccharide is a wall component that is indicative of bacteria, just as beta-glucan is indicative of fungi, and both are intense activators of NF-kB and inflammation.  LPS is released from damaged bacteria, e.g. by antibiotic treatment, binds to receptors on the surface of intestines and stimulates inflammation with release of NO, which produces diarrhea.  Food intolerances, which are based on incomplete digestion of food components, because of an incomplete gut flora (immunological responses/food allergies are rare) are probably also the result of LPS release from gut flora and inflammation.

Innate Immunity is also Triggered by LPS

The basic defenses of humans against microorganisms are mediated at the cellular level by triggering molecules common to all microorganisms, e.g. LPS for bacteria.  The responses are equally general: lysozyme to digest bacterial wall peptidylglycan, lactoferrin that binds iron and yields antibacterial peptides.  LPS (and inflammatory cytokines) also stimulates the liver to produce CRP (C Reactive Protein) that binds to choline on bacteria as the first step in phagocytosis and DNAse I that digests NETs (neutrophil extracellular traps) that are the DNA and histones released by triggered neutrophil cells that enmesh bacteria for engulfment by phagocytic cells.  [NETS plug peripheral catheters and can be cleared with probiotics that stimulate DNAse I release from the liver.]  NETs are also present at sites of inflammation and the accompanying nuclear proteins have the basic triplets that stimulate immune presentation and act as autoantigens, i. e. produce anti-nuclear antibodies, in the absence of adequate Tregs.

Diet and Inflammation

The diagram outlines the interactions that produce the tissue symptoms of inflammation.  Many components of modern diet can trigger inflammation:

Sugars and high glycemic starches raise blood sugar and enhance AGE/HgA1C.

Vegetable oils high in omega-6 oils are converted into inflammatory prostaglandins.

Wheat and other grains have high glycemic starch and insoluble fiber that is inflammatory.  Gluten is inflammatory.

Antibiotics damage the gut flora and produce vitamin deficiencies, autoimmunity and allergies.

Food intolerances result from damaged gut flora and produce gut inflammation.

Fish high in omega-3 EPA and DHA are anti-inflammatory.

The Anti-Inflammatory Diet

Health Results from a Balance of:

Diet (meat, fish, eggs, dairy, vegetables), containing macronutrients of protein, starch 30-100 g/d and fat (low omega 6/3 and saturated fat for most calories), and micronutrients

Soluble Fiber, e.g. resistant starch (consult Free the Animal), inulin, pectin, (plant polysaccharides, animal GAGs)

Gut Flora, diverse and adapted to dietary soluble fiber,

Exercise

Resistant Starch, Panacea, but Why?

Mark’s Daily Apple provides an authoritative diet guide (except for the gut flora).

Heparin, Growth Factors and Rosacea

Knock-out Mice and FGF Receptor Inhibitors Mimic Rosacea
Heparin Nanofibers Loaded with VEGF and FGF Mimic Stem Cells

In previous articles, I have emphasized the mediation of extracellular signaling by heparan sulfate proteoglycans (HSPGs, polysaccharides attached to proteins) and heparin (HS fragments, oligosaccharides) and the sensitivity of HSPG expression and HS degradation by inflammation.  I return to that subject, spurred on by reading two articles that together show both the significance of heparin-mediated growth factors in general and in the specific case of symptom development in rosacea.

FGF Receptor Inhibitors Cause Symptoms Like Rosacea
Fibroblast growth factors stimulate the development of cancers, and antibodies against FGF receptors block cancer growth (see ref.)  FGF receptor inhibiting antibodies are now being used to stop cancers.  Unfortunately,  FGFR antibodies (e.g. cetuximab, panitumumab) also cause symptoms in the skin (telangiectasia, acneiform eruption) similar to the facial inflammation of rosacea.  Similarly, in knock-out mice, that lack the ability to produce FGFR, there are related symptoms.  It appears that lack of some FGF signaling may produce the symptoms of visible blood vessels and pus-filled (though lacking bacteria) follicles of rosacea.

FGF Mediated by HSPG
FGF binds to the heparan sulfate of membrane bound HSPG in pairs and these FGF dimer/heparan sulfate complexes activate a pair of FGF receptors.  The result is activation of protein phosphorylation activity (tyrosine kinase) and normal skin development.  HSPG synthesis is modified by inflammation and heparanase activity is increased.  This suggests that inflammation will decrease FGF signaling and could lead to symptoms of rosacea.

Growth Factors (VEGF, FGF) Bind to Heparin Nanofibers that Mimic Stem Cells
Stem cells produce lots of different growth factors and when stem cells are introduced into damaged cardiovascular tissue, more healing results (see ref.)  To determine if the growth factors produced by the transplanted stem cells was sufficient for the improved healing, fibers made of heparin were dipped into stem cell cultures and the resulting growth factor-coated fibers were injected into damaged tissue.  The heparin-binding growth factors were just as effective at enhancing healing as were the stem cells in previous experiments.  This demonstrated that heparin-binding growth factors were the key to normal repair/revascularization and function.

Rosacea Results from Inflammation and Aberrant Vascularization
Rosacea is poorly understood and is probably numerous diseases that have related symptoms and complex development.  As I indicated in previous articles, neurotransmitters from stimulated facial nerves, enzymes (kallikrein) and cytokines from intestinal interactions with gut flora, mast cell products (heparin, protease) and modified antimicrobial peptides (cathelicidins), as well as cryptic bacteria in facial tissues, may all be involved.  Inflammation in the skin of the face and in the intestines is involved.  Vitamin D, omega-3 fatty acids and anti-oxidants have a variety of responses (sometimes paradoxical) that differ from individual to individual and at different stages in the development of the disease.  Facial inflammation leads to abnormal development of blood vessels (telangiectasia) and in accumulation of lymphocytes and neutrophils (papulopustular rosacea).

Facial Inflammation May Depress HSPG Production and Disrupt FGF Function
One of the key ramifications of persistent facial inflammation may be the depletion of of HSPGs that normally coat cells.  HSPGs are continually produced, reabsorbed and degraded.  The half-life for HSPGs, even those that surround the cells that produce cartilage in connective tissue, is six hours.  HSPGs are also the source of heparin, that is produced as a counter ion bound to histamine and proteases in the secretory granules released by activated mast cells.  Thus, inflammation-based depression of HSPG production, which is also accompanied by heparanase activation, will remove the HSPG coating of cells.  This HSPG coating is needed for normal growth factor function.  Lack of an HSPG matrix on the surface of cells will also result in the migration of growth factors away from where they are normally functional and into adjacent tissue where they may stimulate aberrant development of blood vessels.  This may explain telangiectasia.

Is Topical Heparin a Rosacea Treatment?
Topical heparin does penetrate the skin.  It would appear to be a logical treatment, if HSPG depletion is contributing to symptom development in rosacea.  The length of the heparin fragments may be important.  I am unaware if anyone has tried the heparin lotions that are available for treatment of wounds to minimize scarring, on rosacea.  Heparin may be useful in combination with vitamin D3 and remediation of gut flora in a general scheme to treat rosacea.

refs:
Segaert S, Van Cutsem E.  Clinical signs, pathophysiology and management of skin toxicity during therapy with epidermal growth factor receptor inhibitors.  Ann Oncol. 2005 Sep;16(9):1425-33. Epub 2005 Jul 12.

Webber MJ, Han X, Prasanna Murthy SN, Rajangam K, Stupp SI, Lomasney JW.  Capturing the stem cell paracrine effect using heparin-presenting nanofibres to treat cardiovascular diseases.  J Tissue Eng Regen Med. 2010 Mar 10. [Epub ahead of print]

An Autoantigen for Pancreatitis

Pancreatic Secretory Trypsin Inhibitor (PSTI) Has Internalization Basic Triplet

Pancreatitis is an inflammation of the pancreas resulting from lack of adequate inhibition of proteases. Autoantibodies against PSTI would explain some forms of pancreatitis.

I was researching the maintenance of baby gut flora by mother’s milk, when the reference discussed here was brought to my attention by my wife, who happens to be a lactation consultant. The paper showed that PSTI is present in colostrom, the first milk that a baby gets, before the true milk comes in. PSTI protects the new gut from digestion by its own pancreatic proteases, since PSTI is a protease inhibitor that sticks to the gut.

I naturally assumed that PSTI stuck to the gut by heparin-binding domains that would stick to the heparan sulfate proteoglycans on the gut surface. [Recall that it is via these HSPGs that viruses and bacteria infect the gut and the HSPGs in turn are protected during infections by the release of heparin from mast cells. The heparin in the guts of cattle and pigs are used to make commercial heparin to block blood clotting.] So I looked up the structure (above, with basic amino acids in blue and basic triplet on right) sequence of human PSTI at NCBI:

>gi|190694|gb|AAA36522.1| PSTI
MKVTGIFLLSALALLSLSGNTGADSLGREAKCYNELNGCTKIYD
PVCGTDGNTYPNECVLCFENRKRQTSILIQKSGPC

The basic triplet (RKR,arg-lys-arg), from my perspective, should result in presentation to the immune system during high levels of inflammation, and as a consequence result in autoantibodies against PSTI. The result would be the neutralization of the protease inhibitor and damaging production of active protease to attack the pancreas, i.e. pancreatitis.

It would be fairly easy to test this hypothesis by looking for the anti-PSTI antibodies in some people with pancreatitis. Other autoantibodies, e.g. against tissue transglutaminase, might also be checked, because the inflammation that produced one autoantibody may produce others and both PSTI and tTG are produced in the intestines. In fact, celiac may be the cause of some cases of autoimmune pancreatitis.

Note added in proof:

I just checked the literature on PubMed and found that PSTI is in fact an autoantigen in pancreatitis and produces antibodies against PSTI:
Raina A, Greer JB, Whitcomb DC. Serology in autoimmune pancreatitis. Minerva Gastroenterol Dietol. 2008 Dec;54(4):375-87.

and
I found that pancreatitis is often found associated with celiac (gluten intolerance):
Patel RS, Johlin FC Jr, Murray JA. Celiac disease and recurrent pancreatitis. Gastrointest Endosc. 1999 Dec;50(6):823-7.

ref:
Marchbank T, Weaver G, Nilsen-Hamilton M, Playford RJ. Pancreatic secretory trypsin inhibitor is a major motogenic and protective factor in human breast milk. Am J Physiol Gastrointest Liver Physiol. 2009 Apr;296(4):G697-703.

Suffering from Inflammation?

How do you know if your symptoms result from inflammation?

My interest is the molecular basis of inflammation, how inflammation is triggered and how inflammation contributes to numerous diseases. I try to expose the inflammatory underpinnings of various diseases by initially linking a disease to inflammation and then unraveling the molecular events that lead to and make up the disease.

How Do I Link a Disease to Inflammation?

My first task is to check the biomedical literature to see if there are research articles that support anti-inflammatory interventions that prevent or limit the disease. I just do a PubMed search the disease name plus anti-inflammatory treatments, e.g. omega-3 fish oils, vitamin D, NSAIDs, etc. It is also possible to see if a disease, such as diabetes, that produces chronic inflammation is a risk factor for the new disease being examined. It is shocking to me that omega-3 fish oils (EPA/DHA) or even flax seed oil, have been found to be effective treatments for numerous diseases that range from allergies, arthritis, inflammatory bowel diseases, depression and even septic shock and multiple organ failure. Aspirin has been used to treat infertility and post partum depression, and at high levels to treat cancer.

Dietary Suppression as Prima Fascia Evidence of Inflammatory Cause

If I find that omega-3 oils have been used successfully to treat a disease, then I attempt to link inflammation to the molecular events that initiate the disease. The biomedical literature is of minimal help here. [Biomedical research is usually limited to assessing the impact of drugs on the symptoms of diseases, so the biomedical literature typically does not provide information on the cause of diseases or ways to cure diseases. Causes and cures do not receive research funding.] I have to learn the basic workings of the organs involved and the alterations of function associated with the disease. I have also found by long experience, that major molecular components are systematically missing from typical explanations of function.

Heparan sulfate/heparin Is Missing in Action

Heparan sulfate proteoglycans (HSPGs) dominate the extracellular environment and yet they are systematically excluded from biomedical research. On this blog, I have provided dozens of examples of the essential role played by HSPGs and disruption of these roles by heparin. The majority of cytokines, growth factors, clotting events, complement cascades and even lipid transport (LDL) act via HSPGs. Leaking of proteins into the urine, across the intestines or the blood brain barrier is controlled by HSPGs, is reduced by inflammation and can be partially repaired by heparin. Autoimmune and allergic diseases are initiated by disruptions in HSPG metabolism. Viral and bacterial pathogens bind to human cells via HSPGs. Cancer cells reduce their HSPGs and start to secrete heparanase in order to metastasize. Mast cells secrete heparin! HSPGs and heparin are major players in tissue function and yet the major cell biology text book does not even discuss them. HSPGs are not mentioned in medical school training even though heparin is the most commonly administered drug.

One of the insights that I bring to my conceptualization of diseases is the role of heparan/heparin in cellular physiology. It explains a lot.

Check for Inflammatory Symptoms by Trying the Anti-Inflammatory Diet

If your symptoms are due to inflammation, there is an easy way to find out. Since diet is the biggest source of inflammation and most of the cells of the immune system congregate in your intestines, it makes sense to check to see your health problems are rooted in inflammation by making simple changes in your diet. Since this is just a test, don’t worry about whether or not this is diet for the rest of your life. Just stick to it for a week and see if it changes your life.

The Basic Anti-Inflammatory Diet and Lifestyle Guidelines are here.

(Vitamin D and omega-3 fish oil amounts are minimal levels. More severe examples of inflammation will require higher levels. Vitamin D up to 10,000 IU per day has been found safe. Some individuals require up to 12 fish oil capsule per day to experience relief from symptoms. Increases should be gradual over weeks of time.)

Try it for a week and let me know if your symptoms disappear. The prevalence of diet-based inflammation, makes me confident that you will be glad that you tried these simple, healthy changes. For immediate relief of pain, see my articles on capsaicin, castor oil and menthol/Vicks.

This is not medical advice and is used only in appropriate support of primary medical care.

Extreme Flu Remedies

Experimental Therapies for ARDS, Cytokine Storms

Do not do this at home. There are doctors and hospitals. Use them.

....But, if a doctor emailed me pleading for any ideas that I had to save a bunch of patients suffering from acute respiratory distress syndrome (ARDS) from Tamiflu-resistant H1N1, my first response would be to suggest therapies designed for ARDS from other origins, e.g. burns, septicemia, etc.

Cytokine Storms Are Out of Control
When too much tissue is injured, the local, molecular communication that normally occurs just between cells, spills into the blood stream and becomes potentially lethal. That is what happens in anaphylactic shock. It is also what happens in cytokine storms, where inflammatory cytokines that are normally short-lived and processed locally to progress into recovery, erupt into the blood stream and impact distant organs.

Major disruption of body function by aggressive blood infections or burns over most of the body, will be lethal without heroic medical interventions. These are injuries beyond the evolved adaptations of mammals.  Until recently there were no survivors.

Influenza has been around for a long time. Humans, other mammals and birds get the flu and get over it. Many body cells become infected, antibodies specific to the virus are produced within about a week, the infected cells are killed, the virus is digested and life goes on.

People die from the flu, because an opportunistic pathogen causes a lethal secondary infection, or the body over-reacts and damages itself in attempts to attack its own infected cells. This is a cytokine storm.

Silence the Storms
Cytokine storms can be weathered by blocking the signaling system. Cytokines are just small proteins that are complementary in shape to corresponding protein receptors that penetrate through the surface membranes of cells throughout the body. Binding of cytokine to receptor changes the shape of the receptor and transmits a signal into the cytoplasm of the receptive cell. This turns on aggressive behavior of immune cells and triggers more inflammatory signaling in other cells. This causes fever, malaise, etc.

...But, I was the one the doctor is pleading with to save the people. And I know that there is more to cytokine signaling than just cytokines and receptors. There are also heparan sulfate proteoglycans (HSPGs). Cytokines are not supposed to be broadcast throughout the body. Cytokines function in the space between cells, the extracellular matrix. Polysaccharides attached to membrane proteins, HSPGs, are secreted at one end of the cells, sweep across the surface and are taken back up at the other end. Cytokines have heparan-binding domains and so they stick to the heparan and are swept along. Cytokines can move from one cell to another as the sweeping HSPGs of adjacent cells come in contact.

HSPGs Mediate Cytokine Signaling
The critical point here is that cytokines bind to their receptors with the heparan between -- the cytokine and receptor are like two halves of a bun and the hot dog is the heparan. In fact the heparan bridges two cytokine/receptor complexes to make an active, signaling pentamer.

Heparin Can Block Cytokine Signaling
Heparin is a fragment of heparan sulfate produced by enzymatic degradation of HSPG. Commercial heparin, used to block blood clotting, is obtained from the mast cells of lungs and intestines of hogs and cattle. The mast cells release heparin and histamine in response to parasites or pollen. Since heparin is a short version of heparan sulfate, it can block the formation of active cytokine/receptor complexes.

Heparin is used in a mist to treat the lungs of burn patients. It is also injected into some infertility patients to suppress inflammation that is inhibiting implantation and gestation. It is also effective in treatment of autoimmune inflammation in Crohn’s disease. I think it should be tested as a therapy for H1N1 cytokine storms. It may be useful in nebulizing mists and oral treatment of intestines.

Berberine Binds to HSPG
Berberine is a phytochemical from Barberry traditionally used in the treatment of intestinal infections and arthritis. It also binds to heparan sulfate to form fluorescent complexes visible in microscopy. Berberine-treated mast cells glow brightly. Heparan sulfate can also be detected in Alzheimer’s plaque, atherosclerotic plaque and prion complexes. Because berberine binds to heparan sulfate, it should also disrupt cytokine signaling. It has been used successfully in treatment of septicemic ARDS.

Curcumin Blocks NFkB
One of the most potent chemicals that blocks inflammatory signaling via the inflammatory transcription factor, NFkB, is curcumin. Curcumin is a major component of the spice turmeric. Oral curcumin can be enhanced by co-administration of black pepper, because the piperine in pepper inhibits intestinal inactivation.

Anti-Inflammatory Diet
Of course, I would also recommend vigorous implementation of an anti-inflammatory diet and lifestyle to support any medical treatment.

Niacin Flush

Niacin is a B vitamin that is cheap and highly effective at raising HDL and lowering LDL. HDL and LDL were previously called good and bad cholesterol, resp., but since the data from numerous studies show that they don’t have a big impact on health, it is probably easier to just call them heavy and light reflecting less and more lipid content. If you still want to adjust your blood lipids, then niacin is more effective than the costly statins. Unfortunately, niacin also causes an uncomfortable (itchy and hot) flush.

The niacin flush is part of the inflammatory process that includes the classic tetrad of symptoms: rubor (redness), calor (increased heat), tumor (swelling), dolor (pain). Flushing in response to niacin shows that the immune cells in the skin respond to ingested niacin that is flowing through the capillaries. Mast cells in the skin have receptors that bind niacin and the cells secrete inflammatory prostaglandins. The prostaglandins act on the capillaries to cause dilation and flushing. Mast cells have secretory granules that fuse to the cytoplasmic membrane and release their contents outside. The granules contain histamine, heparin and tryptase. The histamine stimulates histamine receptors on pain/itch nerves and the tryptase stimulates receptors on a second set of pain/itch nerves.

Prostaglandins are produced by membrane bound enzymes on the surface of mast cells. When the mast cells are stimulated, additional enzymes are added to the surface through fusion of the secretory granules. The combined enzyme complex produces prostaglandins by releasing arachidonic acid (ARA) from phospholipids of the membrane (phospholipase A2, PLA2), converting the ARA to an epoxide prostaglandin (cyclooxygenase, COX-1) and stepwise producing additional prostaglandins. These prostaglandins cause the dilation of capillaries that is seen as flushing.

Niacin also binds to receptors on fat cells, adipocytes, and blocks release of fatty acids from the triglycerides stored in these cells. It is this action that is responsible for the increase in HDL and the lowering of LDL in blood serum.

An extension of the niacin skin flushing reaction is the use of this response to demonstrate the presence of arachidonic acid and a functional immune system in the skin. A recent study used topical application of niacin and skin reddening to test the idea that schizophrenia exhausts ARA as a result of inflammatory processes in the brain. Tests showed a tendency for schizophrenic episodes to be accompanied by a diminished flushing response to niacin. This result also suggests that a lowered system-wide ARA level should show up in a predisposition to gut problems.

It would be very interesting to test the interplay between inflammatory provocations, e.g. infection, serum omega-6/omega-3 fatty acids, and measures of inflammation, e.g. C-reactive protein on niacin flushing. Inflammatory depletion of ARA may be important in the decline in the integrity of tissues that is observed in inflammatory diseases of the gut (Helicobacter-based ulcers, IBD, Crohn’s disease, celiac), autoimmune diseases (arthritis, atherosclerosis), skin diseases (vitiligo), etc. It would also be interesting to test the impact of helminth infections to reverse ARA depletion.

reference:
Benyó Z, Gille A, Kero J, Csiky M, Suchánková MC, Nüsing RM, Moers A, Pfeffer K, Offermanns S. 2005. GPR109A (PUMA-G/HM74A) mediates nicotinic acid-induced flushing. J Clin Invest. 2005 Dec;115(12):3634-40.

Mast Cell Heparin

Mast cells are sentinels in tissues. They respond to invading pathogens by releasing their stored histamine, enzymes and heparin. The heparin modifies the activity of enzymes and cytokines.

What are mast cells and why are they loaded with heparin (left)? Mast cells start in the bone marrow, like many other components of the immune system. They then move into the blood stream and offload in most of the tissues that typically encounter pathogens and parasites. Thus, the typical commercial source of the mast cell-produced heparin is pig intestines or cow lungs, i.e. since heparin is made and stored in mast cells and mast cells are abundant in lungs and intestines, those are the sources of crude heparin. Proteins bound to the crude heparin are removed as the heparin is cleaned up to be used as an anti-clotting drug.

Mast cells are sentinels near the surface of mucus membranes that line the airways of the lungs and the digestive tract. Diseases of the lungs and intestines, e.g. asthma and inflammatory bowel disease, that have an inflammatory and/or autoimmune component yield high levels of mast cells in the affected tissues. Pathogens or parasites coming in contact with mast cells trigger the sudden release of vesicles full of histamine, enzymes and heparin.

Heparin stored in vesicles in mast cells can also be readily visualized by staining the mast cells in microscope sections using the fluorescent dye berberine (left). Berberine binds quite specifically to heparin and is also used in herbal medicine as a treatment for many inflammatory diseases, such as arthritis. It would be very interesting to know whether berberine has any effect on asthma.

Mast cells display a variety of receptor proteins on their surfaces. Protein receptors work by binding target molecules, ligands, changing their shapes and transmitting a signal through the cytoplasm. A key aspect of the signal transmission is the requirement for the ligand binding to bring together receptors in pairs. The pairing of receptors during ligand binding is facilitated by the binding of heparin to both ligands and receptors. Two ligands, e.g. cytokine peptides, such as TNF, can bind to adjacent sites on a heparin molecule and this pair can then bind to two receptors brought together on the surface of a cell. The receptors bind to the ligand and to the heparin. Some ligands will bind to their receptors without heparin, but the presence of heparin greatly accelerates and intensifies the reactions.

Heparin is synthesized in the vesicles of mast cells and binds to enzymes, e.g. tryptase, also present in the vesicles. The tryptase enzyme proteins form tetramers with heparin wrapped around the edge (left, edge view showing one pair of tryptase proteins with heparin bound diagonally to blue heparin-binding domains; other pair of tryptase proteins is hidden).

Interestingly the active site for each tryptase in the tetramer faces a hole where the four proteins come together. Thus the tetramer can degrade small peptides, but large proteins cannot get access to the blocked active sites. Monomers change shape and are no longer active.

Activated mast cells release their vesicle contents with some enzymes active and their bound heparin is replaced by the heparan sulfate attached to adjacent cells. Other enzymes are initially inactive bound to heparin and are activated by dissociation of the heparin once they are released from the vesicles. In both cases some of the heparin is released from the mast cells into the surrounding tissue. The free heparin can bind to cytokines released from other cells and the combined pairs of cytokines bound to heparin can in turn bind to appropriate receptors on other cells. The abundance of heparan sulfate bound to other cells will determine whether additional heparin is required for receptor responses from particular cytokines. Cells with abundant heparan sulfates will sweep heparin binding ligands toward receptors aggregated in lipid rafts, as the heparan sulfate proteoglycans are internalized for recycling.

Mast cells can be activated by allergens, because of IgE receptors. IgEs are antibodies that trigger allergic responses. The IgEs produced by antibody producing B lymphocytes circulate in the blood serum and bind to mast cell receptor proteins. Allergen molecules bind to the IgE-receptor complexes, trigger the activation of the mast cells and release histamine. The histamine binds to receptors on other cells and produces the symptoms of allergy or asthma.
Heparin can be sprayed into the lungs of asthma sufferers and reduce symptoms. This suggests that the ratio of heparin to cytokines is important and that cytokine signaling required for asthma episodes of airway constriction can bind individually to different heparin molecules and minimize mast cell triggering and histamine release.

Asthma also responds to a general decrease in chronic systemic inflammation. Thus, an anti-inflammatory diet and lifestyle, can reduce episodes and potentially reverse symptoms. Omega-3 oils and glucosamine, for example are both effective.

Tryptase model: Sommerhoff CP, Bode W, Pereira PJ, Stubbs MT, Stürzebecher J, Piechottka GP, Matschiner G, Bergner A. 1999. The structure of the human betaII-tryptase tetramer: fo(u)r better or worse. Proc Natl Acad Sci U S A 96(20):10984-91.


Berberine staining of mast cell heparin: Feyerabend TB, Hausser H, Tietz A, Blum C, Hellman L, Straus AH, Takahashi HK, Morgan ES, Dvorak AM, Fehling HJ, Rodewald HR. 2005. Loss of histochemical identity in mast cells lacking carboxypeptidase A. Mol Cell Biol. 25:6199-210.