Environmental risk factors in multiple sclerosis

[Wilberforce]

NEW LINK PPV
Environmental risk factors in multiple sclerosis
Lauer
http://www.tandfonline.com/doi/abs/10.1586/ern.10.7

The etiology of multiple sclerosis is, at present, not definitely known, but genetic and environmental
factors play a role in its causation. Environmental causes have a predominant impact. Epidemiologic
research has contributed considerably to the identification of external risk factors in this multifactorial
setting, but methodological constraints still play a major part. Viral and other microbial agents have
drawn much attention, although none of them is a necessary condition for the disease. This is true
also for the Epstein–Barr virus, for which most data, including prospective data, supports a role in
the majority of multiple sclerosis patients. In parallel, the hypothesis is still attractive in that it is not
the virus per se, but rather more the age when it infects the human being that is the crucial matter.
Other risk factors, such as tobacco smoking and vitamin D deficiency, which have immunomodulating
properties, may also play some role, although the latter is not compatible with all data of the
descriptive epidmiology of multiple sclerosis. Diet might be of considerable importance, all the more
since multiple sclerosis can be ecologically attributed to a certain food patterns and is inversely
associated with others (e.g., the ‘Mediterranean diet’). The hypothesis that the preservation of meat
by nitrite and wood smoke plays a role, and the protective influence of a fish and, possibly, a vegetable
diet, are supported by some studies, but methodological constraints limit, at present, definite conclusions.
A new avenue is the search for an interaction between genetic and environmental causes, and also
between several environmental factors that might lead to new approaches for prevention and, perhaps,
for the treatment of multiple sclerosis.

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Sausage Preservation Methods and the Prevalence of Multiple Sclerosis: An Ecological Study
Lauer
http://www.tandfonline.com/doi/abs/10.1 ... 0601093300
PPV
http://www.tandfonline.com/doi/pdf/10.1 ... 0601093300

Abstract
Sausage preservation methods (smoking vs. drying), as classified by Hippisley Coxe and Hippisley Coxe (1986), were compared with the prevalence of multiple sclerosis (MS) in 26 countries. Meat, pork, and animal fat consumption, divided by food energy intake, were taken as covariates. In logistic regression smoke preservation, meat consumption and animal fat consumption showed a significant association with MS in univariate analysis. In multiple logistic regression, smoke preservation was associated with MS independently from meat and pork consumption, whereas animal fat contributed with borderline significance. The data suggest an association between sausage preservation by smoking and MS. A possible causal link should be studied further by individual-based epidemiological approaches.

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Notes on the Epidemiology of Multiple Sclerosis, with Special Reference to Dietary Habits
Klaus Lauer
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3975352/

Abstract
Sausage preservation methods (smoking vs. drying), as classified by Hippisley Coxe and Hippisley Coxe
(1986), were compared with the prevalence of multiple sclerosis (MS) in 26 countries. Meat, pork, and
animal fat consumption, divided by food energy intake, were taken as covariates. In logistic regression
smoke preservation, meat consumption and animal fat consumption showed a significant association
with MS in univariate analysis. In multiple logistic regression, smoke preservation was associated with
MS independently from meat and pork consumption, whereas animal fat contributed with borderline
significance. The data suggest an association between sausage preservation by smoking and MS.
A possible causal link should be studied further by individual-based epidemiological approaches.

[Wilberforce]

Testing Method Promising for Spinal Cord Injuries, Multiple Sclerosis

June 14, 2013 — A medical test previously developed to measure a toxin found in tobacco smokers has been adapted to measure the same toxin in people suffering from spinal cord injuries and multiple sclerosis, offering a potential tool to reduce symptoms.

The toxin, called acrolein, is produced in the body after nerve cells are injured, triggering a cascade of biochemical events thought to worsen the injury's severity. Acrolein (pronounced a-KRO-le-an) also may play an important role in multiple sclerosis and other conditions.

Because drugs already exist to reduce the concentration of acrolein in the body, being able to detect and measure it non-invasively represents a potential treatment advance, said Riyi Shi (pronounced Ree Shee), a professor of neuroscience and biomedical engineering in Purdue University's Department of Basic Medical Sciences, School of Veterinary Medicine, Center for Paralysis Research and Weldon School of Biomedical Engineering.

"If the acrolein level is high it needs to be reduced, and we already have effective acrolein removers to do so," Shi said. "Reducing or removing acrolein may lessen the severity of symptoms in people who have nerve damage, but there has not been a practical way to monitor acrolein levels in nervous system trauma and diseases."

The toxin is present in tobacco smoke and air pollutants. A method had been developed previously to detect and measure acrolein in the urine of smokers, but it has not been used in people suffering from conditions in which the body produces acrolein internally.

"Based on this method, it was revealed that acrolein is significantly elevated in smokers and decreases following the cessation of cigarette smoke," Shi said. "However, such a method has not been widely used for conditions in which acrolein is elevated due to central nervous system damage or disease."

The researchers tested the method in laboratory animals.

"We wanted to see if higher levels of acrolein corresponds to greater severity of spinal cord injury, and the answer is yes," said Shi, who is working with Bruce Cooper, director of the Metabolite Profiling Facility in the Bindley Bioscience Center of Purdue's Discovery Park. "This means reducing acrolein may help to control symptoms."

New findings are detailed in a research paper that recently appeared online in the Journal of Neurotrauma. The paper, which also will appear in an upcoming print edition of the journal, was authored by doctoral students Lingxing Zheng, Jonghyuck Park, Michael Walls and Melissa Tully; Amber Jannasch, laboratory manager of the Metabolite Profiling Facility; and Cooper and Shi.

The method does not detect acrolein directly but determines the presence of a byproduct, or metabolite, of acrolein in the urine. The metabolite is a chemical compound called N-acetyl-S-3-Hydroxypropylcysteine, or 3-HPMA.

"Acrolein is very volatile, so it doesn't remain stable long enough to monitor, but one molecule of acrolein will make one molecule of 3-HPMA, which is very stable in urine," Shi said.

Laboratory rats were injected with different doses of acrolein, and findings showed that the detection technique is able to accurately measure these differences in acrolein concentration in the urine. The technique might one day be performed routinely in a doctor's office.

"The non-invasive nature of measuring 3-HPMA concentrations in urine allows for long-term monitoring of acrolein in the same animal and ultimately in human clinical studies," Shi said.

Two drugs have been shown to be effective in reducing acrolein levels in the body: hydralazine and phenelzine, which have been approved by the U.S. Food and Drug Administration for hypertension and depression, respectively.

The testing method could be used in conjunction with other measures to test patients for the progress of spinal cord disease.

"Nervous system trauma and diseases are like many other illnesses: A disease-associated marker can be critical for making a diagnosis, a therapeutic selection and a treatment evaluation," Shi said. "Therefore, determination of acrolein levels gives you more assurance that you have an intense biochemical imbalance and biochemical damage and that you should use an acrolein scavenger as a treatment. We used different levels of hydralazine to see if it causes a dose-dependent reduction of 3-HPMA and found that, in fact, it did. This shows that this method is capable of monitoring the decrease of acrolein through treatment with acrolein-removing medications."

Acrolein damages mitochondria, which provide energy for cells, and in multiple sclerosis compromises the myelin sheath surrounding a nerve cell's axon, preventing nerves from properly conducting electrical impulses. The toxin has a possible role in other diseases, including Alzheimer's disease, cancer and atherosclerosis.

"Due to widespread involvement of acrolein in the body, the benefits of this study have the potential to significantly enhance human health," Shi said. "For example, there is evidence that heightened levels of acrolein could diminish an individual's ability to recover fully from stroke and cancer."

In laboratory animals, hydralazine has been shown to delay onset of multiple sclerosis for several days, which could mean several years in humans. Tests with animals also suggests the drug could help to reduce the most severe symptoms once the disease has progressed.

Acrolein has been found to be elevated by about 60 percent in the spinal cord tissues of mice with a disease similar to multiple sclerosis. The toxin causes harm by reacting with the proteins and lipids that make up cells, including neurons.

The research is funded by the National Institutes of Health. Previous work was supported with funding from the state of Indiana.

source
http://www.sciencedaily.com/releases/20 ... 082850.htm