Key Points
- Scientists have found a key weakness in the dangerous gut parasite Cryptosporidium.
- The parasite relies on a molecule called squalene, produced by human cells, to protect itself from stress.
- The parasite cannot make its protection, making the host’s squalene a critical lifeline.
- A forgotten cholesterol drug, lapaquistat, was found to block squalene production and stop the infection in mice.
Scientists have discovered a new way to combat a life-threatening intestinal parasite by severing one of its most vital lifelines. The breakthrough involves repurposing an old, abandoned cholesterol drug that has shown remarkable success in treating the infection in mice, as part of a study published in Cell.
The parasite Cryptosporidium is a major cause of severe diarrhea, particularly in young children and individuals with weakened immune systems. There are currently no fully effective treatments.
In a new study, researchers at the Francis Crick Institute utilized CRISPR gene-editing technology to test thousands of human genes, identifying which ones the parasite requires for survival. They identified a significant weakness in the human cell’s cholesterol production process.
The team discovered that the parasite’s survival hinges on a molecule called squalene. When squalene levels are high, the parasite is protected from a type of cellular stress. The parasite cannot produce its protection against this stress, so it must hijack the host cell’s system, rendering it incredibly vulnerable.
Armed with this knowledge, the researchers looked for a way to cut off the parasite’s squalene supply. They found a forgotten drug called lapaquistat, which was originally developed to treat high cholesterol but was later abandoned.
The drug works by blocking the production of squalene. When they gave lapaquistat to mice infected with Cryptosporidium, it significantly reduced the infection and stopped further intestinal damage.
Because lapaquistat has already undergone safety testing in the past, researchers hope it can be fast-tracked for human clinical trials, offering new hope against this deadly parasite.
