Quite a large body of research literature is building in support of the idea that chronic inflammation is a major cause of many degenerative diseases. One of the causes of chronic inflammation is obesity.
In research published in the Sept 21 issue of Circulation, the researchers show for the first time that circulating mononuclear cells -- the body's monocytes (the largest type of white blood cell) and lymphocytes -- exist in a proinflammatory state in obese persons known to be at increased risk of developing diabetes, heart disease or both.
"These cells are creating a lot of nuisance in the obese," said Paresh Dandona, M.D., Ph.D., head of UB's Division of Endocrinology, Diabetes and Metabolism and senior author on the study. "They enter the artery and set up atherosclerosis. They activate fat cells to produce more proinflammatory factors. They interfere with insulin signaling, causing insulin resistance. They even enter the brain."
Husam Ghanim, Ph.D., research associate, is first author on the study.
The good news, said Dandona, is that, based on these findings, the status of mononuclear cells from one blood sample could serve as an easy early-warning system for the risk of developing insulin resistance and circulatory problems.
The research was conducted using fasting blood samples from 16 normal-weight subjects with an average body mass index (BMI) of 22.6 and from 16 obese subjects with an average BMI of 40. All participants had similar glucose levels and were taking no anti-inflammatory medication. The research was conducted at the Diabetes-Endocrinology Center of Western New York located in Kaleida Health's Milliard Fillmore-Gates Hospital.
Mononuclear cells were isolated, and proinflammatory and anti-inflammatory factors within the nucleus and the cell were assayed. The researchers also calculated an insulin-resistance index for each participant, using a standard formula.
Results showed that measures of proinflammatory factors were significantly higher in blood samples from obese subjects than the average weight subjects, while levels of factors that normally inhibit inflammation were significantly lower.
"This proinflammatory state may contribute to insulin resistance," said Dandona, "because the cytokines produced may interfere with insulin action." The index of insulin resistance in the obese subjects was nearly three times higher, on average, than that of the normal subjects, findings showed.
Lose excess weight to lower your level of body-wide inflammation and you will live longer as a result.
The randomized trial was conducted from June 2001 to January 2004 at a university hospital in Italy among 180 patients (99 men and 81 women) with the metabolic syndrome. Patients in the intervention group (n=90) were instructed to follow a Mediterranean-style diet and received detailed advice about how to increase daily consumption of whole grains, fruits, vegetables, nuts, and olive oil; patients in the control group (n=90) followed a prudent diet (carbohydrates, 50 percent-60 percent; proteins, 15 percent-20 percent; total fat, less than 30 percent).
The researchers found that after 2 years, patients in the Mediterranean diet intervention group had significant decreases in body weight, blood pressure, levels of glucose, insulin, total cholesterol, and triglycerides and a significant increase in levels of high-density lipoprotein cholesterol, all of which were greater than those recorded in the control group. Serum concentrations of interleukins 6 (IL-6), 7 (IL-7), and 18 (IL-18) and high-sensitivity C-reactive protein (hs-CRP) were significantly reduced in patients in the intervention group compared with those in the control group. Endothelial function score improved in the intervention group but remained stable in the control group. Forty patients consuming the intervention diet still had features of the metabolic syndrome, compared with 78 patients consuming the control diet. Participants who followed the intervention diet showed a reduction in the number of the components of the syndrome such that the overall prevalence of the metabolic syndrome was reduced by approximately one half.
You can also read the abstract of the Journal of the American Medical Association paper of the previous report.
Elevatation of inflammation marker high-sensitivity C Reactive Protein (hs-CRP) correlates with greater arterial plaque build-up and therefore greater risk of heart disease and other circulatory ailments.
The study of 386 Olmsted County, Minn., residents used transesophageal echocardiography (TEE) to obtain high-quality images of the lining of the aorta, the main artery through which the heart pumps blood to the body. TEE images are clearer than traditional echocardiograms because they come from an ultrasound probe inserted down the throat. This enables imaging of the heart and major blood vessels without interference from the ribs and chest wall.
The researchers found partial blockages, called atherosclerotic plaques, in the aortas of 69 percent of the study subjects, whose median age was 66. The level of high-sensitivity C-reactive protein (hs-CRP), a marker in the bloodstream that indicates inflammation, was the single factor most closely associated with the presence of plaques and their severity.
Emotional states have a large influence on blood levels of C Reactive Protein and the risk of circulatory and heart-related ailments. Anger and depression increase the risks of heart disease .
In earlier studies, Suarez has shown that people who are prone to anger, hostility and depressive symptoms respond to stress with increased production of the stress hormone norepinephrine. Scientific evidence suggests that an increase in this stress hormone activates the inflammatory arm of the immune system and triggers the expression of genes that cause chronic, low-grade inflammation. This inflammation is characterized by high levels of CRP, he said.
"Individuals with these psychological attributes may evaluate their environment in a cynically hostile manner, and thus respond with greater anger, which is often accompanied by mild to moderate symptoms of depression," said Suarez. "These psychological attributes tend to cluster within the same individual, and the clustering of attributes may produce even greater risk than any single trait alone."
Suarez said the levels of depressive symptoms and angry/hostile moods necessary to raise CRP do not constitute psychiatric conditions. "That is, you don't have to be clinically depressed or have extreme and frequent bouts of anger to show higher levels of CRP," he said.
In the Duke study, 121 healthy men and women were asked to complete standard personality questionnaires in which they described their psychological attributes, including anger, hostility and depression. The volunteers did not have any pre-existing conditions -- such as smoking, high blood pressure, diabetes or heart disease -- that would predispose them to having high CRP levels. High-sensitivity blood tests were then conducted to measure CRP levels.Respondents who were prone to anger, had high hostility levels, and showed mild to moderate symptoms of depression had two to three times higher CRP levels than their calmer counterparts. The more pronounced their negative moods, the higher CRP levels they had, the study showed.
The highest levels of CRP were in the range of 1.7 mg/L to 3.0 mg/L. While these levels are still considered relatively low – fever, an active infection, or physical trauma is associated with CRP levels above 10.0/mg/L –CRP levels in this range are associated with a moderate to high risk of heart attacks and strokes, said Suarez.
Stay skinny. Eat great food. Also, be careful with your thoughts since they have a lot of impact upon your body. Avoid anger and depression. Plus, since exercise lowers inflammation markers and brightens the mood working out is good for your mental and physical health.
|Share |||Randall Parker, 2004 September 23 01:48 AM Aging Studies|