Researchers (from left) Munna Sarkar, Sutapa Mondal and #38; Hirak Chakraborty

A class of pain relieving drugs has shown new promise in inducing membrane fusion in small vesicles1. This new function of non-steroidal anti-inflammatory drugs (NSAIDs) could help formulate new therapies for diseases like cancer.

Membrane fusion leads to mixing of internal contents of cells. This is an integral process in many biological events such as fertilization of eggs by sperm, viral invasion of cells and transport of proteins inside the cells. To study drug-induced membrane fusion, the researchers took three NSAIDs — piroxicam, meloxicam and tenoxicam and small vesicles made of dimyristoylphosphatidylcholine (DMPC), the natural phospholipid component of biological membranes. The small vesicles were treated with drugs and compared to untreated ones.

The study has found that the three drugs are capable of inducing membrane fusion. Sophisticated imaging techniques showed several fusion bodies arrested at the different stages of the fusion process. These were seen in the drug treated vesicles but not in untreated ones.

"We have shown that piroxicam can rupture mitochondrial membrane leading to release of cytochrome C, a protein that activates certain enzymes triggering the controlled death of cells," says lead researcher Munna Sarkar from the chemical sciences division of Saha Institute of Nuclear Physics, Kolkata. This is an important strategy to trigger mass death for cancer cells, she adds.