Lactic acid bacteria can “activate” the human immune system

Recently, a new German study found out why yogurt is good for the human body. The metabolites of common bacterial lactic acid bacteria in fermented foods, when combined with a cellular receptor present in the human body, can signal “activate” the immune system. The findings, published in the journal Science Public Library and Genetics, provide a perspective for researchers to understand the benefits of fermented foods at a molecular level and will help identify potential drug targets for the treatment of inflammatory diseases.

This cellular receptor is a protein, and there are only two HCA receptors in most animals, but a third HCA receptor exists in humans and apes. The researchers found that a metabolite produced by lactic acid bacteria, D-phenyl lactic acid, binds to a third HCA receptor and signals immune cells to trigger immune cell activity. Studies have suggested that the third type of HCA receptor first appeared in the common ancestor of humans and apes, and this evolutionary character changed the eating habits of human ancestors, allowing them to start eating fermented food.

One of the authors, Claudia Staubert, a researcher at the University of Leipzig in Germany, said that in the future they will further study how the lactic acid bacteria metabolite D-phenyl lactic acid affects the immune system.

Excessive or too little sleep can have a negative impact on the brain

When the human body sleeps less than 7 hours or more than 9 hours a day, it will have a negative impact on cognitive functions such as visual memory and reaction time. The researchers tested data from nearly 400,000 participants from the UK Biobanking and International Alzheimer’s Genomics Project. Among them, the test results of visual memory indicate that people who sleep less than 7 hours will increase their mistake rate by 5% for every hour of sleep; those who sleep for more than 9 hours will make more mistakes, that is, each Sleep more than 1 hour, the error rate increased by 9%. On average, the tester is given 1 hour of sleep per day, so the response time in the visual memory test will be 1% slower and the error rate will increase by 3%.

Albert Henry, a Ph.D. student at the University of London School of Cardiology, said: “Our research provides new data that proves that both short sleep and long sleep can have a negative impact on certain cognitive areas. Such as visual memory and reaction time. The study illustrates the importance of sleep time on brain memory and cognitive function, suggesting that improving sleep habits may be beneficial to brain memory and cognitive health.

India synthesizes new compounds that kill cancer cells

Researchers at the Indian Institute of Chemical Biology have designed and synthesized 25 quinoline derivatives and patented them. The anticancer mechanism of the novel quinoline derivatives is similar to the existing topoisomerase 1 inhibitor drugs, but has a stronger ability to kill cancer cells.

Topoisomerase 1 is a basic enzyme that plays a crucial role in DNA replication. It binds to DNA molecules to form a complex and cleaves one strand of DNA, causing the DNA molecules to unwind from the helix. When the DNA molecule is unfolded, topoisomerase 1 will re-add the cleavage DNA strand to repair and replicate.

The proliferation of cancer cells far exceeds that of healthy cells, and the amount of topoisomerase 1 produced is much higher than that of normal cells, so topoisomerase 1 can form more complexes with DNA molecules. Existing topoisomerase-1 inhibitor anticancer drugs can only temporarily trap this complex, and the broken DNA strand will be repaired within about 20 minutes.

After research and testing, the newly synthesized 25 quinoline derivatives inhibited topoisomerase 1 significantly better than existing drugs, and can trap the complex formed by topoisomerase 1 and DNA molecules for up to 5 hours.