Obese people are 10 times more likely to develop diabetes than people who are underweight. Scientists have been exploring the fundamental connection between the two. Previously, people believed that the main problem of obese diabetes was abnormal insulin activity, that is, the body could not prevent the dangerous release of fatty acids. However, the latest research by a team including Rutgers University at New Brunswick in the United States has found that the problem is not with "brake failure", but rather with a sudden increase in neurotransmitters in the liver and other tissues when stepping on the "gas pedal". Scientists have found the key in the sympathetic nervous system that triggers the human body's "fight or flight" response. New research suggests that a high-fat diet can cause a surge in neurotransmitters throughout the body, leading to rapid breakdown of adipose tissue in the liver, which is typically regulated by insulin release. The focus of this study is on insulin resistance. Scientists have long known that diabetes worsens when insulin cannot effectively reduce blood sugar levels. But they are more interested in understanding the essence of insulin resistance. The team also turned their attention to the sympathetic nervous system, which is responsible for delivering neurotransmitters such as norepinephrine to tissues throughout the body. They fed mice edited with neurotransmitter related genes with foods rich in fats such as lard, coconut oil, and soybean oil. During the observation period of over two months, mice that had undergone gene editing had similar food intake, weight gain, and insulin signaling activity as those without gene editing. However, in genetically edited mice, there was no increase in fat tissue breakdown and insulin resistance, and ultimately no signs of fatty liver or worsening tissue inflammation were observed. The unedited mice showed insulin resistance, aggravated inflammation, and signs of liver disease. This means that neurotransmitters are the culprits causing insulin resistance and related problems. Scientists say that drugs that block neurotransmitter activity related to the sympathetic nervous system have not yet shown benefits in obese populations. If these drugs can target specific tissues and avoid affecting the brain, it may be more promising. (New Society)