The effects of poor eating habits persist even after diet is improved

November 03, 2014

Almost everyone knows that improving your eating habits will most likely improve your health. What most people may not know, however, is that the effects of poor eating habits persist long after dietary habits are improved. In a new report appearing in the November 2014 issue of the Journal of Leukocyte Biology, scientists use mice to show that even after successful treatment of atherosclerosis (including lowering of blood cholesterol and a change in dietary habits) the effects of an unhealthy lifestyle still affect the way the immune system functions. This change in function occurs largely because poor eating habits alter the way genes express themselves, including genes related to immunity. This change in gene expression (epigenetics) ultimately keeps the risk of cardiovascular disorders higher than it would be had there been no exposure to unhealthy foods in the first place.

"I hope that this study demonstrates the importance of diet-induced changes in the epigenome and encourages further research into the interaction between dietary patterns, DNA methylation and disease," said Erik van Kampen, a researcher involved in the work from the Division of Biopharmaceutics at the Leiden Academic Centre for Drug Research at Leiden University in Leiden, The Netherlands.

To make their discovery, scientists used two groups of mice that had an altered gene making them more susceptible to developing high blood cholesterol and atherosclerosis. These mice were either fed a high-fat, high-cholesterol diet (Western-type diet, WTD) or a normal diet (chow). After a long period of feeding, bone marrow was isolated from the mice and transplanted into mice with a similar genetic background that had their own bone marrow destroyed. The recipient mice were left on chow diet for several months, after which the development of atherosclerosis in the heart was measured. The number and status of immune cells throughout the body and epigenetic markings on the DNA in the bone marrow also were examined. They found that DNA methylation, an epigenetic signature, in the bone marrow was different in mice that received bone marrow from the WTD-fed donors compared to the mice receiving bone marrow from chow-fed donors. Furthermore, these mice had large differences in their immune system and increased atherosclerosis.

"We've long known that lifestyle and nutrition could affect immune system function," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. "The ability of nutritional history to have durable affects on immune cells demonstrated in this new report could have profound implications for treatment of diseases with immune underpinnings. The length of such effects will be critical to determine and it will be interesting to examine the effects of drugs that can modify epigenetics."
-end-
Erik van Kampen, Armand Jaminon, Theo J. C. van Berkel, and Miranda Van Eck. Diet-induced (epigenetic) changes in bone marrow augment atherosclerosis. J. Leukoc. Biol. November 2014 96:833-841; doi:10.1189/jlb.1A0114-017R. http://www.jleukbio.org/content/96/5/833.abstract

The Journal of Leukocyte Biology publishes peer-reviewed manuscripts on original investigations focusing on the cellular and molecular biology of leukocytes and on the origins, the developmental biology, biochemistry and functions of granulocytes, lymphocytes, mononuclear phagocytes and other cells involved in host defense and inflammation. The Journal of Leukocyte Biology is published by the Society for Leukocyte Biology.

Federation of American Societies for Experimental Biology

Related Immune System Articles from Brightsurf:

How the immune system remembers viruses
For a person to acquire immunity to a disease, T cells must develop into memory cells after contact with the pathogen.

How does the immune system develop in the first days of life?
Researchers highlight the anti-inflammatory response taking place after birth and designed to shield the newborn from infection.

Memory training for the immune system
The immune system will memorize the pathogen after an infection and can therefore react promptly after reinfection with the same pathogen.

Immune system may have another job -- combatting depression
An inflammatory autoimmune response within the central nervous system similar to one linked to neurodegenerative diseases such as multiple sclerosis (MS) has also been found in the spinal fluid of healthy people, according to a new Yale-led study comparing immune system cells in the spinal fluid of MS patients and healthy subjects.

COVID-19: Immune system derails
Contrary to what has been generally assumed so far, a severe course of COVID-19 does not solely result in a strong immune reaction - rather, the immune response is caught in a continuous loop of activation and inhibition.

Immune cell steroids help tumours suppress the immune system, offering new drug targets
Tumours found to evade the immune system by telling immune cells to produce immunosuppressive steroids.

Immune system -- Knocked off balance
Instead of protecting us, the immune system can sometimes go awry, as in the case of autoimmune diseases and allergies.

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.

Parkinson's and the immune system
Mutations in the Parkin gene are a common cause of hereditary forms of Parkinson's disease.

How an immune system regulator shifts the balance of immune cells
Researchers have provided new insight on the role of cyclic AMP (cAMP) in regulating the immune response.

Read More: Immune System News and Immune System Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.