Medical Forum / General / Nutrition / July 2009
Inflammation wars: Smoke 'em if you got 'em!
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Taka - 16 Jul 2009 14:48 GMT Scientific American; Jun2006, Vol. 294 Issue 6, p24-24, 1p, 1 color
HOW NICOTINE STOPS INFLAMMATION COULD LEAD TO NEW DRUGS
Body Blazes, Lisa Melton
* Nicotine has undergone * an image overhaul, at least biomedically. In the past few years researchers have found that the substance can alleviate symptoms of ailments such as Alzheimer's disease and ulcerative colitis. Just how nicotine battles these foes, however, has remained unclear. Now, by studying sepsis, Luis Ulloa of North Shore University Hospital in Manhasset, N.Y., has evidence elucidating nicotine's biochemical pathways that could lead to more potent anti-inflammatory drugs.
Sepsis, the most lethal of inflammatory conditions, is a bacterial invasion of the bloodstream. The third leading cause of death in the developed world, it accounts for nearly 10 percent of overall deaths in the U.S. every year. Infection causes part of the damage, but what makes patients critically ill is their own fiercely aggressive immune response. Macrophages churn out huge quantities of proinflammatory cytokines. This exaggerated immune response leads to tissue damage, and eventually the patient dies of cardiovascular dysfunction and multiorgan failure.
Ulloa and his collaborators have found something remarkable: nicotine can shut down this overshooting inflammatory response, to the point of reversing sepsis in mice. As far as anti-inflammatory treatments go, this is powerful stuff. "Nicotine taps into the body's own potent anti-inflammatory mechanisms," Ulloa explained in February at a Novartis Foundation meeting in London. "That is the beauty of our approach. By using nicotine, we are copying physiological mechanisms that have been selected by evolution to modulate the immune system."
Specifically, nicotine mimics acetylcholine, the Cinderella of neurotransmitters. Largely ignored over the years, acetylcholine has been catapulted into a starring role, linking the nervous and the immune systems. Through acetylcholine the nervous system controls the inflammatory fires that constantly crop up in our bodies. Receptors for acetylcholine reside not only on nerve cell endings but also on immune cells. Nicotine binds and activates these receptors, allowing cross talk between the brain and immune system.
"This is something quite phenomenal," comments Wouter de Jonge of the Academic Medical Center Amsterdam, who studies how macrophages respond to acetylcholine. "Smokers suffering from ulcerative colitis seemed to benefit from their habit, so there were hints that nicotine could ameliorate inflammatory diseases, but nobody could get a handle on it," he notes.
Now Ulloa's group may have provided an explanation for the positive effects that nicotine has on illnesses as diverse as schizophrenia, Alzheimer's, Parkinson's disease, Tourette's syndrome and ulcerative colitis. In laboratory experiments, Ulloa demonstrated that nicotine latches onto the nicotinic receptors on macrophages and stops them from spewing out inflammatory cytokines. This clampdown is brutally effective. The researchers also identified the specific receptor subtype, the alpha-7 acetylcholine receptor, that nicotine binds in macrophages to stop cytokine production.
But as a drug, nicotine is fraught with toxicity issues. Apart from its addictive nature, it can lead to cardiovascular problems and contribute to cancer. "No one is looking to use nicotine to treat inflammation," Ulloa says. "We want to design specific compounds that will target this receptor to take advantage of nicotine's anti-inflammatory effects while eluding its collateral toxicity."
"This is one of the great stories in immunology in the past few years— no question about it," remarks Mitchell Fink, an expert in critical care medicine at the University of Pittsburgh. A selective nicotinelike compound may be a promising therapy not only for sepsis but for a whole slew of chronic conditions, including heart disease, cancer and diabetes. The task at hand is to find the best surrogate for nicotine. Ulloa's petri dishes are the ones to watch.
A NICK OF NICOTINE
As a potent anti-inflammatory, nicotine can damp down a dangerous immune response. But it is too risky as a treatment. Fortunately, substitutes may exist. Pharmaceutical firms have developed nicotinelike drugs, such as GTS-21, that were designed to stimulate the alpha-7 acetylcholine receptors in the brains of patients with Alzheimer's disease. But the clinical trials failed to show a clear benefit, and the drugs were dropped. The compounds may have been unable to cross the blood-brain barrier—which would actually be a plus for an anti-inflammatory, because then it could target the periphery and avoid the brain. Researchers have begun testing such substitutes to combat inflammation.
Taka - 16 Jul 2009 14:56 GMT doi:10.1016/S0306-4530(97)00076-0
Effect of nicotine on the immune system: Possible regulation of immune responses by central and peripheral mechanisms
Nicotine (NT) treatment impairs T-cell receptor (TCR)-mediated signaling, leading to the arrest of T cells in the G1 phase of the cell cycle and inhibition of the antibody plaque-forming cell (AFC) response to sheep red blood cells (SRBC). This paper summarizes some of the previous findings related to cigarette smoke/NT and the immune response, and presents preliminary evidence suggesting that mice chronically treated with NT (0.5 mg/day/kg body weight) have a depressed inflammatory response in the turpentine-induced abscess model of inflammation. This ability of nicotine to attenuate an inflammatory response may also be the cause of reduced mortality of chronically nicotine-treated mice from acute influenza A pneumonitis. Moreover, in LEW rats, decreased anti-SRBC AFC responses were also observed after intracerebroventricular (ICV) administration of relatively small concentrations of NT (28 μg/day/kg body weight) which, when given peripherally, did not affect the AFC response. In vitro the addition of NT to T cells increased protein tyrosine kinase (PTK) activity and intracellular Ca2+ concentration [Ca2+]i. These results support the hypothesis that NT alters immune responses by directly interacting with T cells, as well as indirectly through brain- immune interactions.
Adv Exp Med Biol. 1998;437:279-89.
Nicotine-induced modulation of T Cell function. Implications for inflammation and infection.
Sopori ML, Kozak W, Savage SM, Geng Y, Kluger MJ. Pathophysiology Division, Lovelace Respiratory Research Institute, Albuquerque, New Mexico 87108, USA.
Tobacco smoking may predispose humans to respiratory disease, and may be a compounding risk factor in HIV infection and progression to AIDS. We have demonstrated that chronic exposure of mice and rats to cigarette smoke or nicotine inhibits T cell responsiveness, which may account for the decreased antibody response to T-dependent antigens seen in these animals. This inhibition may result from aberrant antigen-mediated signaling and depletion of IP3-sensitive Ca2+ stores in nicotine-treated animals. Moreover, nicotine appears to moderate the inflammation associated with turpentine-induced sterile abscess and influenza infection. These anti-inflammatory properties of nicotine may account for longer survival of nicotine-treated than control mice lethally infected with influenza virus. However, because inflammation is required for clearance of many pathogens, nicotine- treated mice exhibit significantly higher titers of influenza virus following infection. These results offer an explanation for the higher susceptibility to some infectious diseases, but greater resistance to some inflammatory diseases among human smokers. PMID: 9666281
nightlight - 23 Jul 2009 17:44 GMT > doi:10.1016/S0306-4530(97)00076-0 > > Effect of nicotine on the immune system: Possible regulation of immune > responses by central and peripheral mechanisms Nicotine doesn't account for the full range of anti-inflammatory effects of tobacco smoke. Take a look at the recent (2009) mice experiment testing 'nicotine vs tobacco smoke vs controls' effects on mice model of rheumatiod arthritis -- while both nicotine and tobacco smoke were shown to be protective (delaying the RA onset), tobacco smoke was much more protective against the rogue antibodies after the RA onset:
In section "Ameliorating effect of cigarette smoke exposure on antibody production" (pg 4, text above Fig 3):
-- quote
Levels of specific IgG against collagen II in mice exposed to cigarette smoke were significantly lower seven weeks after immunization compared with non-smoking controls (P < 0.05) in two independent experiments (Figure 3a). However, animals treated with nicotine did not show statistical differences in levels of specific antibodies to collagen type II (data not shown). These data are consistent with clinical findings showing no differences in arthritis index between the groups (Figure 2a). Intriguingly, the number of aCCP- positive animals was significantly lower in mice exposed to cigarette smoke, with only one out of 22 animals testing positive for IgG aCCP whereas in the non-smoking controls five out of 16 were positive (P < 0.05; Figure 3b). The total frequency of aCCP in CIA was low (5/38 mice, 13%). These data clearly indicate that cigarette smoke decreased the ability to produce antibodies against collagen II and aCCP. ---
http://arthritis-research.com/content/11/3/R88
nightlight - 17 Jul 2009 00:46 GMT That's merely a tip of the iceberg for this ancient medicinal plant. Here are few beneficial effects of tobacco smoke (most not due to nicotine):
1. Upregulates glutathione (by 80%), catalase and SOD (by 100%).
2. Selective MAO B inhibition (by 40%), much safer and more harmonious with overall biochemistry than via selegiline. Smokers in their 50s have MAO B of non-smokers in their 20s.
3. Dopamine (throughout the body, including brain), acetylcholine and norepinephrine are also stimulated directly (protective & therapeutic for ADD, Tourette, anxiety, depression, schizophrenia).
4. Upregulates pregnenolone, DHEA and testosterone and slows down their decline with age (protective against endometrial cancer & endometriosis).
5. Upregulates telomerase and suppresses apoptosis (protects against Alzheimer's, Parkinson's, also via 1,2 & 3; e.g. resulting in tenfold lowered rates for early onset Alzheimer's, twelvefold for early Parkinson's; protective in strokes & spinal injuries).
6. Upregulates vascular growth factor (via nicotine CO, NO).
7. Provides CoQ10 (which is even manufactured from tobacco) & niacin directly into arterial bloodstream.
8. Upregulates neutrophiles (by 20%)
9. Reduces appetite and increase basal metabolism.
10. Suppresses amyloidosis throughout tissues, not just brain
12. Improves insulin sensitivity, protects against & alleviates diabetes.
13. Anti-inflammatory effects at multiple levels, from T-cells through CNS vagus/'cholinergic anti-inflammatory' pathway (therapeutic & protective against asthma, allergies, ulcerative colitis, IBD, colon cancer, apthous ulcers, arthritis, pre-eclampsia, endotoxemia, polymicrobial sepsis...)
14. Downregulates IGF-1
15. Downregulates NF-kB
16. Upregulates bFGF (basic fibroblast growth factor) and MMPs (expression of several matrix metalloproteinases)
17. Increases BDNF (brain-derived neurotrophic factor) expression
18. Reduces TNF-alpha and increases adiponectin (adipocyte effects)
... and so on.
The net effect is that smoking animals (such as mice, rats, hamsters, dogs,... even those smoking at 5+ packs/day equivalents) live about 20% longer, stay 10-15% thinner and sharper throughout. Smokers are over-represented among supercentenarians and, among others the oldest man and the oldest women ever were smokers (the only two humans who lived over 120). The current oldest man is also a lifelong smoker. The oldest marathon runner (completed London marathon at age 101) even smoked few cigarettes during the marathon.
After 6+ decades of massive efforts to demonstrate experimentally any harm at all from inhalation of tobacco smoke, pharma sponsored antismoking researchers still don't know how to shorten the lifespans of test animals via inhalation of tobacco smoke, short of gross smoke asphixiation (you could cause same kind of overdose harm with plain water and it's easier to overdose on water than on tobacco smoke).
The entire antismoking "science" (sponsored and publicised mainly by Big Pharma, which battles and suppresses as much as it can all other natural & folk medicines as well) rests entirely on blind statistical correlations on non-randomized (self-selected subjects) samples of smoking with 'smoking related diseases'. Such non-randomized correlations are equally consistent with beneficial and causal role of tobacco smoke in those diseases. This is no different than observing that people using statins or blood pressure medications will have more heart attacks than those not using them. Or that people wearing sunglasses will have more sunburns and skin cancers thn those not wearing them. Sunglasses are merely a statistical marker for sun exposure. Similarly, use of tobacco smoke is a proxy for any exposure or biochemical/genetic malfunction for which the enumerated effects are protective and therapeutic.
For example, the upregulation of the main internal antixoidants & detox enzymes (1), implies that tobacco smoking will protect against and alleviate the harmful effects of most industrial and environmental toxins, hence people suffering such toxic exposures, or those especially sensitive to them, would perceive tangible benefits from smoking due to doubled detox rates (this has been experimentally verified animal experiments and observed in human studies), thus they would smoke more than general population, resulting thus in statistical correlations with diseases (e.g. lung cancer, copd) caused by the very same toxins against which tobacco smoke is protective.
See references & further discussions here:
Site: Smoking is good for you (a friend who liked ideas) http://www.wispofsmoke.net/goodforyou.html
Some online books & papers for the above page http://www.wispofsmoke.net/goodreads.html
The Scientific Scandal of Antismoking http://members.iinet.com.au/~ray/TSSOASb.html
Discussion 1 (imminst/nootropic forum) http://www.imminst.org/forum/index.php?s=afe84afcd59328b5da1c047f937d72a0&showto pic=15125&view=findpost&p=166023
Discussion 2 (imminst/nootropic forum) http://www.imminst.org/forum/index.php?showtopic=24284&st=0&p=263376&#entry263376
Discussion in nootropic section of m&m forum http://www.mindandmuscle.net/forum/index.php?showtopic=35287&st=30&p=508486&#ent ry508486
Harm from quitting http://forum.ryorevolution.com/viewtopic.php?p=14089#p14089
Refs & discussion of longevity experiments & facts http://www.freerepublic.com/focus/news/2262644/posts?page=#13
Amyloidosis effects http://scholar.google.com/scholar?num=50&hl=en&lr=&safe=off&q=amyloidosis+%28nic otine+OR+tobacco%29&btnG=Search
Neurotrophic effects http://scholar.google.com/scholar?hl=en&q=neurotrophic+effects+%28nicotine+OR+to bacco%29&btnG=Search
Neuroprotective effects http://scholar.google.com/scholar?hl=en&q=neuroprotective+effects+%28nicotine+OR +tobacco%29&btnG=Search
Petr Skrabanek (books in pdf format) * Follies and Fallacies in Medicine http://www.curezone.com/upload/pdf/books/Follies-and-Fallacies-in-Medicine-1up.pdf * Death of Humane Medicine http://www.curezone.com/upload/pdf/books/Death-of-Humane-Medicine.pdf * False Premises False Promises http://www.curezone.com/upload/pdf/books/False-Premises-False-Promises.pdf
John Hasenkam - 20 Jul 2009 09:10 GMT Thanks Taka,
I read about this linkage years ago and it has always fascinated me. Central Ach modulates systemic inflammation, at a big guess I imagine because it energises the hippocampal region, a possible downstream effect of this being modulation of the PVN. BIG guess. Ach is known to boost nerve growth factor production, and coffee consumption also provides an Ach boost. Good Ach levels are vital for memory. Ach is the first neurotransmitter that takes a plummet in Alz and some other neurodegenerative disorders. Drugs for Alz typically target Ache, an enzyme that breaks down Ach. There, is, however, an interesting alternative:
Mol. Pharmaceutics, 3 (6), 773 -777, 2006. 10.1021/mp060066m S1543-8384(06)00066-9
Web Release Date: August 9, 2006
Copyright © 2006 American Chemical Society
A Molecular Link between the Active Component of Marijuana and Alzheimer's Disease Pathology
Lisa M. Eubanks, Claude J. Rogers, Albert E. Beuscher IV, George F. Koob, Arthur J. Olson, Tobin J. Dickerson, and Kim D. Janda*
Departments of Chemistry, Immunology, and Molecular Biology, Molecular and Integrated Neurosciences Department, The Skaggs Institute for Chemical Biology, and Worm Institute for Research and Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
Received June 11, 2006
Abstract:
Alzheimer's disease is the leading cause of dementia among the elderly, and with the ever-increasing size of this population, cases of Alzheimer's disease are expected to triple over the next 50 years. Consequently, the development of treatments that slow or halt the disease progression have become imperative to both improve the quality of life for patients and reduce the health care costs attributable to Alzheimer's disease. Here, we demonstrate that the active component of marijuana, 9-tetrahydrocannabinol (THC), competitively inhibits the enzyme acetylcholinesterase (AChE) as well as prevents AChE-induced amyloid -peptide (A) aggregation, the key pathological marker of Alzheimer's disease. Computational modeling of the THC-AChE interaction revealed that THC binds in the peripheral anionic site of AChE, the critical region involved in amyloidgenesis. Compared to currently approved drugs prescribed for the treatment of Alzheimer's disease, THC is a considerably superior inhibitor of A aggregation, and this study provides a previously unrecognized molecular mechanism through which cannabinoid molecules may directly impact the progression of this debilitating disease.
Keywords: Cannabinoids; Alzheimer's disease; acetylcholinesterase
Scientific American; Jun2006, Vol. 294 Issue 6, p24-24, 1p, 1 color
HOW NICOTINE STOPS INFLAMMATION COULD LEAD TO NEW DRUGS
Body Blazes, Lisa Melton
* Nicotine has undergone * an image overhaul, at least biomedically. In the past few years researchers have found that the substance can alleviate symptoms of ailments such as Alzheimer's disease and ulcerative colitis. Just how nicotine battles these foes, however, has remained unclear. Now, by studying sepsis, Luis Ulloa of North Shore University Hospital in Manhasset, N.Y., has evidence elucidating nicotine's biochemical pathways that could lead to more potent anti-inflammatory drugs.
Sepsis, the most lethal of inflammatory conditions, is a bacterial invasion of the bloodstream. The third leading cause of death in the developed world, it accounts for nearly 10 percent of overall deaths in the U.S. every year. Infection causes part of the damage, but what makes patients critically ill is their own fiercely aggressive immune response. Macrophages churn out huge quantities of proinflammatory cytokines. This exaggerated immune response leads to tissue damage, and eventually the patient dies of cardiovascular dysfunction and multiorgan failure.
Ulloa and his collaborators have found something remarkable: nicotine can shut down this overshooting inflammatory response, to the point of reversing sepsis in mice. As far as anti-inflammatory treatments go, this is powerful stuff. "Nicotine taps into the body's own potent anti-inflammatory mechanisms," Ulloa explained in February at a Novartis Foundation meeting in London. "That is the beauty of our approach. By using nicotine, we are copying physiological mechanisms that have been selected by evolution to modulate the immune system."
Specifically, nicotine mimics acetylcholine, the Cinderella of neurotransmitters. Largely ignored over the years, acetylcholine has been catapulted into a starring role, linking the nervous and the immune systems. Through acetylcholine the nervous system controls the inflammatory fires that constantly crop up in our bodies. Receptors for acetylcholine reside not only on nerve cell endings but also on immune cells. Nicotine binds and activates these receptors, allowing cross talk between the brain and immune system.
"This is something quite phenomenal," comments Wouter de Jonge of the Academic Medical Center Amsterdam, who studies how macrophages respond to acetylcholine. "Smokers suffering from ulcerative colitis seemed to benefit from their habit, so there were hints that nicotine could ameliorate inflammatory diseases, but nobody could get a handle on it," he notes.
Now Ulloa's group may have provided an explanation for the positive effects that nicotine has on illnesses as diverse as schizophrenia, Alzheimer's, Parkinson's disease, Tourette's syndrome and ulcerative colitis. In laboratory experiments, Ulloa demonstrated that nicotine latches onto the nicotinic receptors on macrophages and stops them from spewing out inflammatory cytokines. This clampdown is brutally effective. The researchers also identified the specific receptor subtype, the alpha-7 acetylcholine receptor, that nicotine binds in macrophages to stop cytokine production.
But as a drug, nicotine is fraught with toxicity issues. Apart from its addictive nature, it can lead to cardiovascular problems and contribute to cancer. "No one is looking to use nicotine to treat inflammation," Ulloa says. "We want to design specific compounds that will target this receptor to take advantage of nicotine's anti-inflammatory effects while eluding its collateral toxicity."
"This is one of the great stories in immunology in the past few years— no question about it," remarks Mitchell Fink, an expert in critical care medicine at the University of Pittsburgh. A selective nicotinelike compound may be a promising therapy not only for sepsis but for a whole slew of chronic conditions, including heart disease, cancer and diabetes. The task at hand is to find the best surrogate for nicotine. Ulloa's petri dishes are the ones to watch.
A NICK OF NICOTINE
As a potent anti-inflammatory, nicotine can damp down a dangerous immune response. But it is too risky as a treatment. Fortunately, substitutes may exist. Pharmaceutical firms have developed nicotinelike drugs, such as GTS-21, that were designed to stimulate the alpha-7 acetylcholine receptors in the brains of patients with Alzheimer's disease. But the clinical trials failed to show a clear benefit, and the drugs were dropped. The compounds may have been unable to cross the blood-brain barrier—which would actually be a plus for an anti-inflammatory, because then it could target the periphery and avoid the brain. Researchers have begun testing such substitutes to combat inflammation.
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