Health and Medical News and Resources

General interest items edited by Janice Flahiff

Effects of environmental toxicants reach down through generations

Effects of environmental toxicants reach down through generations

From the 2 March 2012 article at Science News Daily

 Washington State University researcher has demonstrated that a variety of environmental toxicants can have negative effects on not just an exposed animal but the next three generations of its offspring.

English: Environmental contamination with pest...

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The animal’s DNA sequence remains unchanged, but the compounds change the way genes turn on and off — the epigenetic effect studied at length by WSU molecular biologist Michael Skinner and expanded on in the current issue of the online journalPLoS ONE.

While Skinner’s earlier research has shown similar effects from a pesticide and fungicide, this is the first to show a greater variety of toxicants — including jet fuel, dioxin, plastics and the pesticides DEET and permethrin — promoting epigenetic disease across generations…

The field opens new ground in the study of how diseases develop. While toxicologists generally focus on animals exposed to a compound, Skinner’s work further demonstrates that diseases can also stem from older, ancestral exposures that are then mediated through epigenetic changes in sperm.

The study was funded by the U.S. Army to study pollutants that troops might be exposed to. Skinner and his colleagues exposed pregnant female rats to relatively high but non-lethal amounts of the compounds and tracked changes in three generations of offspring.

The researchers saw females reaching puberty earlier, increased rates in the decay and death of sperm cells and lower numbers of ovarian follicles that later become eggs. Future studies can use the molecular tools for risk assessment analysis

March 5, 2012 Posted by | Public Health | , , , , , , , | Leave a comment

You are what your father ate

You are what your father ate
UMMS research suggests paternal diet affects lipid metabolizing genes in offspring

From the December 23, 2010 Eureka news alert

WORCESTER, Mass. — Scientists at the University of Massachusetts Medical School and the University of Texas at Austin have uncovered evidence that environmental influences experienced by a father can be passed down to the next generation, “reprogramming” how genes function in offspring. A new study published this week in Cell shows that environmental cues—in this case, diet—influence genes in mammals from one generation to the next, evidence that until now has been sparse. These insights, coupled with previous human epidemiological studies, suggest that paternal environmental effects may play a more important role in complex diseases such as diabetes and heart disease than previously believed.

“Knowing what your parents were doing before you were conceived is turning out to be important in determining what disease risk factors you may be carrying,” said Oliver J. Rando, MD, PhD, associate professor of biochemistry & molecular pharmacology at UMMS and principal investigator for the study, which details how paternal diet can increase production of cholesterol synthesis genes in first-generation offspring….

…These observations are consistent with epidemiological data from two well-known human studies suggesting that parental diet has an effect on the health of offspring. One of these studies, called the Överkalix Cohort Study, conducted among residents of an isolated community in the far northeast of Sweden, found that poor diet during the paternal grandfather’s adolescence increased the risk of diabetes, obesity and cardiovascular disease in second-generation offspring. However, because these studies are retrospective and involve dynamic populations, they are unable to completely account for all social and economic variables. “Our study begins to rule out the possibility that social and economic factors, or differences in the DNA sequence, may be contributing to what we’re seeing,” said Rando. “It strongly implicates epigenetic inheritance as a contributing factor to changes in gene function.”

The results also have implications for our understanding of evolutionary processes, says Hans A. Hofmann, PhD, associate professor of integrative biology at the University of Texas at Austin and a co-author of the study. “It has increasingly become clear in recent years that mothers can endow their offspring with information about the environment, for instance via early experience and maternal factors, and thus make them possibly better adapted to environmental change. Our results show that offspring can inherit such acquired characters even from a parent they have never directly interacted with, which provides a novel mechanism through which natural selection could act in the course of evolution.” Such a process was first proposed by the early evolutionist Jean-Baptiste Lamarck, but then dismissed by 20th century biologists when genetic evidence seemed to provide a sufficient explanation.

Taken together, these studies suggest that a better understanding of the environment experienced by our parents, such as diet, may be a useful clinical tool for assessing disease risk for illnesses, such as diabetes or heart disease. “We often look at a patient’s behavior and their genes to assess risk,” said Rando. “If the patient smokes, they are going to be at an increased risk for cancer. If the family has a long history of heart disease, they might carry a gene that makes them more susceptible to heart disease. But we’re more than just our genes and our behavior. Knowing what environmental factors your parents experienced is also important.”

The next step for Rando and colleagues is to explore how and why this genetic reprogramming is being transmitted from generation to generation. “We don’t know why these genes are being reprogrammed or how, precisely, that information is being passed down to the next generation,” said Rando. “It’s consistent with the idea that when parents go hungry, it’s best for offspring to hoard calories, however, it’s not clear if these changes are advantageous in the context of a low-protein diet.”

 

 

December 27, 2010 Posted by | Medical and Health Research News, Nutrition | , , , , , , , | Leave a comment

Farm Environment, Cats Help Kids Avoid Skin Disease & Related Article (Growing Up on Farm Strengthens Immune System)

Farm Environment, Cats Help Kids Avoid Skin Disease

HealthDay news image

European researchers report rural living less likely to lead to atopic dermatitis for infants

Childhood exposure to germs in the environment strengthens their immune system, according to current scientific evidence. (See  Immune System (http://www.niaid.nih.gov/topics/immuneSystem/Pages/immunity.aspx) by the National Institute of Allergy and Infectious Diseases [NIAID])

Now it seems that the environment not only confers immunity through not only interacting with a child’s immune system after birth, but before birth.

Excerpts from a recent Health Day news article by Robert Preidt

WEDNESDAY, Dec. 8 (HealthDay News) — The children of mothers who were around farm animals and cats during pregnancy are less likely to develop atopic dermatitis in their first two years of life, new European research shows.

Atopic dermatitis (also called atopic eczema) is a chronic and painful inflammation of the skin that frequently occurs in childhood. The condition affects up to 20 percent of children in industrialized countries and is one of the most common childhood skin diseases….

….Along with the first finding, the researchers also identified two genes associated with a child’s reduced risk of developing atopic dermatitis in the first two years of life.

The findings support the theory that a gene-environment interaction with a child’s developing immune system influences the development of atopic dermatitis, said the researchers.

The study appears in the Journal of Allergy & Clinical Immunology.***
[The abstract of the article may be found here]

Previous research has found that allergies are less likely in children who grow up on farms and whose mothers lived on farms during their pregnancy.

SOURCE: Journal of Allergy & Clinical Immunology, news release, Dec. 2, 2010

Click here for suggestions on how to get the full text of the article

 

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Growing Up On A Farm Directly Affects Regulation Of The Immune System

From the 9 February 2012 Medical News Today article

Immunological diseases, such as eczemaand asthma, are on the increase in westernised society and represent a major challenge for 21st century medicine. A new study has shown, for the first time, that growing up on a farm directly affects the regulation of the immune system and causes a reduction in the immunological responses to food proteins. …

…Dr Marie Lewis, Research Associate in Infection and Immunity at the School of Veterinary Sciences, who led the research, said: “Many large-scale epidemiological studies have suggested that growing up on a farm is linked to a reduced likelihood of developing allergic disease. However, until now, it has not been possible to demonstrate direct cause and effect: does the farm environment actively protect against allergies, or are allergy-prone families unlikely to live on farms?” ,,,

 


December 12, 2010 Posted by | Consumer Health | , , , , , , , , , | 2 Comments

   

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