In concomitant studies, researchers at the Cleveland Clinic in the United States discovered new mechanisms that show why and how often taking red meat can increase the risk of heart disease and the role of gut bacteria in this process.
The study, led by Stanley Hazen, is based on the previous section, which shows that TMAO (trimethylamine N-oxide), a side product of intestinal bacteria produced during digestion, can lead to the development of cardiovascular diseases, including heart attacks and cerebrovascular disorders TMAO occurs when digestive bacteria digest cholin, lecithin and carnitine, nutrients rich in animal products such as red meat and liver and other animal products.
In a new foods study published Monday in the European Heart Journal, scientists found that the diet rich in red meat as the primary source of protein in circulation significantly increases TMAO levels compared to diets with white meat or not as meat source of protein.
The study showed that chronic red meat consumption improved the formation of TMAO through the microbes in the gut and decreased the effectiveness of the kidneys in elimination. This increased production and the reduction in elimination caused by red meat diet contribute to an increased concentration of TMAO, which is associated with the development of atherosclerosis and complications of heart disease.
High blood pressure TMAO has proven to be a powerful tool for predicting the future risks of heart attack, stroke and death, according to previous studies conducted by Dr. Hazen and his team, and then it all over again. TMAO tests are now in clinical use. Dr. Hazen presides over the Department of Cellular and Molecular Medicine at the Lerner Research Institute of the Cleveland Clinic and is head of the Department of Cardiac Prevention and Cardiac Rehabilitation at Miller Heart and the Vascular Institute.
The study included 113 participants who randomly received comprehensive meal plans prepared with protein sources of red meat, white meat or without meat (mostly vegetarian), at 25 percent of the daily calories. All participants followed a cleansing diet between meals.
After one month on a red meat diet, the vast majority of participants in the study experienced an increase in blood pressure and urinary levels of TMAO. On average, blood TMAO levels in the blood of red meat increased approximately three times compared to white meat or meat, and some patients increased by more than ten times. Similar increases were observed in the urine. After the patients stopped taking red meat, the levels of TMAO in blood and urine decreased in the following month.
Changes in renal function
The work also revealed an unexpected finding that the chronic diet of participants affected the functioning of the kidneys by changing the efficacy of the kidneys to eliminate the compounds. For example, while red meat diet reduced TMAO secretion, the red meat diet increased the efficacy of carnitine secretion and other metabolites derived from carnitine.
"As we know, the first study shows that the kidneys can change the efficacy of which they excrete various ingredients, depending on the diet they eat, except salts and water," says Dr. Hazen, which also runs the Clinical Microbiome Center and Human Health Cleveland.
"We know that lifestyle factors are critical to cardiovascular health, and these findings are based on our previous TMAO linkage study with heart disease. They provide additional evidence on how food interventions can be effective treatment strategies to reduce TMAO levels and reduce consequent risk of heart disease, "adds.
In another study, published in the Journal of Clinical Investigation, Hazen and his research team revealed a new potential goal to prevent cardiovascular disease by going deeper into the intestinal microbial route that transforms carnitine into TMAO.
Scientists have found that carnitine, an abundant nutrient in red meat and some energy drinks and additives, is converted into TMAO in a gut in two steps, facilitated by various intestinal bacteria. The team found that the first step is similar to all omnivores (butchers) and vegans / vegetarians. However, in the second part, the formation of TMAO significantly improves throughout the meat.
Then, researchers have shown that the daily addition of carnitine can cause TMAO production, including for vegans and vegetarians, who still eat the usual diet. Earlier this year, Hazen and her team published an article showing how the researchers designed a new potential class of drugs for the prevention of heart disease and the risk of coughing with microbial pathway disorders that became the TMAO cholin
The Hazen team compared the effect of daytime oral carnitine supplements on omnivores versus vegetarians / vegans. At the beginning, vegans / vegetarians had limited capacity to produce TMAO from carnitine, while omnivores quickly produced TMAO. After one month of completion, both groups showed increased capacity for TMAO production.
"It is surprising that vegans and vegetarians make it difficult to form TMAOs from dietary carnitine. A new astonishing finding on the pathway caused by the introduction of carnitine, although only as a capsule supplement, contains important information on new MAOI inhibition procedures that can help reduce the risk of cardiovascular disease, "says Hazen, the head of the Jan Bleeksma Chair in AAScular Cell Biology and Atherosclerosis.
It concludes: "By discovering this new path, we can potentially develop new treatments that would break this process before the development and progression of cardiovascular disease."