Imbalance in pH value may be a cause of Alzheimer's disease, a study has found. A study conducted by Johns Hopkins Medicine scientists have found new evidence in lab-grown mouse brain cells, called astrocytes, that one root of Alzheimer's disease may be a simple imbalance in acid-alkaline-or pH-chemistry inside endosomes, the nutrient and chemical cargo shuttles in cells. Astrocytes work to clear so-called amyloid beta proteins from the spaces between neurons, but decades of evidence has shown that if the clearing process goes awry, amyloid proteins pile up around neurons, leading to the characteristic amyloid plaques and nerve cell degeneration that are the hallmarks of memory-destroying Alzheimer's disease. To measure the pH balance within endosomes without breaking open the astrocyte, researchers used pH-sensitive probes that are absorbed by endosomes and emit light based on pH levels. The experiment successfully reversed the pH problem and improved the capacity for amyloid beta clearance. The study appeared in the Proceedings of the National Academy of Sciences journal. The disease that affects 50 million people worldwide has no cure or no drugs, till date.