A study by scientists at the university of Texas health science center shows that eating a high-fat, high-sugar diet causes the accumulation of harmful fat in the liver to continue even after a low-sugar, low-fat diet.
In the study, published in the journal Cell, researchers developed a nanoscale sensor that can detect and track fat accumulation levels in the liver. They used it to assess the effects of a high-fat, high-sugar diet on the livers of mice. Later, after restoring the mice to a healthy diet, they evaluated the results. The researchers found that while the fat accumulation decreased after a healthy diet, some of the residual fat remained in some liver cells.
"The liver remembers even shorter, unhealthy diets," says Maria c. Carrillo of the university of Texas health science center. In the United States, up to 40 percent of people are affected by high-fat, high-sugar diets. In patients with nonalcoholic fatty liver, excess fat accumulates in the liver. The condition can develop into more serious diseases, including inflammation and even liver cancer. "Fatty liver disease is getting more and more attention clinically," says hepatologist Dr. Robert Schwartz, an assistant professor at Weill Cornell medical college. "Right now, we don't have drugs for fatty liver. We tell patients to eat better and exercise more, but the results are not very good."
Currently, ultrasound or magnetic resonance imaging can help identify patients with fatty liver, but not in detail. The nanosensors developed by the researchers are the first non-invasive sensors to detect fat in the lysosomes of kupffer cells, potentially identifying dangerous cells. When the nanosensors are injected into mice, they undergo a series of transport and are eventually dissolved by lysosomes. Then irradiate the animals with near-infrared devices, which make the sensors glow. The shaded areas match the amount of fat in the liver, making it possible to measure fat noninvasively. At the same time, these nanosensors can also help speed up the research and treatment of liver diseases. And may improve diagnosis.