Researchers have found that in rats with hepatic encephalopathy, brain changes occur even before the onset of symptoms.
The liver is important for the body: it acts as a filter at about 1.7 liters per minute. Also, when he is sick, many unwanted substances enter the human body and can lead to psychological, motor and neurocognitive disorders. For example, when the liver is malfunctioning, too much ammonium can reach the brain, which produces too much glutamine production and can trigger brain edema or hepatic encephalopathy. This neuropsychiatric syndrome can go as far as coma.
Researchers from Swiss universities have been interested in how this disease works. According to their study to appear in the September edition of Journal of Hepatologyit would reach the brain even before touching other organs. Eventually, this discovery could detect brain damage related to liver diseases by brain analysis even before the first symptoms.
For eight weeks, researchers observed rats with chronic liver disease. "We tracked each animal individually by placing it every two weeks in a high magnetic field MRI (9.4 Tesla) to perform high-resolution spectroscopy (SRM), allowing us to observe the alterations very accurately. of the early onset of liver disease, and we have made unpublished observations! "says Dre. Cristina Cudalbu, research scientist and operational manager of the 9.4T MRI at the Center for Biomedical Imaging at the Swiss Federal Institute of Technology Lausanne (EPFL).
Less vitamin C and creatine
Because researchers discovered molecular changes in the animal's brain as early as the second week of liver disease. Either before the rats even show physical symptoms. "Based on previous studies, we thought it took about six weeks to see an impact - the beginning of the deterioration of the animal's health status," says Cristina Cudalbu.
This degradation finally began to appear between the fourth and the eighth week. The animals then presented states of jaundice and malnutrition, suffering from water in the belly. "From that moment, we have observed in the brain that in addition to an excess of ammonium, the rate of two other molecules suddenly drops: vitamin C, an antioxidant, and creatine, which fulfills many functions including energy "says Olivier Braissant, professor at the Department of Clinical Chemistry of the Vaud University Hospital Center (CHUV) and the Faculty of Biology and Medicine of the University Center of Lausanne (UNIL).
This is the first time that researchers have demonstrated the intervention of these two molecules in hepatic encephalopathy. According to them, they appear after the rise of ammonium in the blood.
See if human brain damage is similar to that of rats
Thus, an SRM brain scan could detect neurological manifestations of chronic liver disease before the onset of symptoms. But researchers also want to determine whether it would be possible to protect the brain from this deterioration or to reduce it, for example by compensating for the lack of creatine and vitamin C by supplements or probiotics. "We are also doing similar observations in humans, to see if brain damage is similar to that of rats," they conclude.
At present, the diagnosis of hepatic encephalopathy takes place from the symptoms and the results of examinations (blood tests, mental examination, electroencephalography ...). The manifestations of this complication, which occurs as a result of acute liver failure or chronic hepatitis, result mainly in the deterioration of the brain function of the patient whose consciousness is disturbed. At first, it may exhibit mood swings and impaired judgment. He has more and more trouble sleeping, becomes depressed, anxious or irritable and may have trouble concentrating.
As the affliction progresses, its breath will start to smell sweetish and musty. Then, he will struggle to keep hands in a stable position by stretching his arms and will present involuntary muscle twitches. The speech also slows down and the patient is more and more disoriented, agitated, excited. Sometimes the progression of hepatic encephalopathy is such that the affected person loses consciousness and falls into a coma, which usually leads to death.
Fortunately, there are treatments available to cure hepatic encephalopathy. The doctor will try to eliminate toxic substances from the patient's intestines. For example, he may prescribe antibiotics, put him on a diet low in meat and other animal proteins, and give him lactulose. Ingested, this synthetic sugar acts as a laxative by accelerating the passage of food and thus decreases the amount of ammonia absorbed by the body.