Blood-Brain barrier It is a selective membrane structure, which allows only very few molecules to penetrate the bloodstream into the brain cells. Because of the barrier, it is not easy to transfer drugs directly through the bloodstream – whether it is drug -injected drugs, or they are swallowed and should be absorbed in the blood through the digestive system. One way to bypass the barrier is to transfer medication through the nasal caves, where a tissue is called the smell. Epithelial cells expect parts of the body’s organs; The smelling epithelium includes, among other things, smell receptors: the nervous system cells, which are directly connected to the Olafactory Bulb – that is, to the area in the brain responsible for the sense of smell. However, in the drops or spray to the nose, only a little of the drug can be consumed, and some of the small quantity is expected to be absorbed in the respiratory tract of the respiratory system, and not reach the smell. In order to overcome the problem, researchers engineering bacteria that live in the nasal caves to secrete drugs that will come directly to the brain.
The article was originally published on the Davidson Institute for Scientific Education
The nasal caves populate an harmless bacterial population, which is permanently living there. In a published study In the journal Cell, Matthew Wok Chang and his colleagues, from the National University of Singapore, asked to check if they could be used to transfer medication to the brain. The researchers found that the bacterium for Lactobacillus Plantarum is only on the baked in humans, but not on the respiratory epithelium. The researchers added a fluorescent color to the bacteria and found that when dripping them into a nose of mice, the bacteria only concentrate on the bouncing epithelium, although after about 72 hours, the amount of bacteria decreases three to four times the amount in the first 24 hours. Additional tests found a large amount of bacteria in the feces of the mice and colon, which probably indicates the removal of excess bacteria through the digestive system over time. When the researchers engineered the bacteria so that the fluorescent material is excited out – and so it can be seen – they found that the material reaches the odor attack, and from there to the rest of the brain, especially the forehead.
Weight – but less
In order to examine whether this method has the therapeutic value, the researchers engineered the bacteria to secrete hormones from an appetite that operate in the brain. They drip daily a small amount of bacteria for lean mice noses, and at the same time they began to provide them with high -fat food. After eight weeks the weight of the mice in the control group, which were not treated with bacteria, rose by about a third – seven grams, on average. In contrast, the weight of the mice treated with bacteria rose only to three grams, and their fat tissues were smaller.
The researchers also conducted a sugar loading test, which examined a prenatal condition-blood sugar levels that are considered higher than the norm, and may develop into type 2 diabetes. In another experiment, the researchers compared mice who received bacteria for mice who received the drug itself in nose drops. The drug slowed the weight, but bacterial treatment was more effective. The researchers believe that such treatment may be an effective way to transfer medication to the brain.
In another study, published in the journal Cell Systems, the Mark Gek Research Group from the University of Pompeo Fabra in Spain, leather bacteria called Coutibacterium Acnes) so that antioxidant enzymes are to protect skin damage from oxidative damage. The researchers also engineered molecular detectors to feel radiation and retry the antioxidants. The system they developed in cell culture, but has not yet been tried for a real living.
If so, it seems that harmless bacteria may be used in the future as medical technology. With which we can transfer drugs directly to the brain, or other places in the body that are difficult to treat, and perhaps to protect ourselves from the sun’s radiation.