Hope of Alzheimer's cure soon, says scientists in Calcutta

Scientists in Calcutta have announced that using a protein from a parasite to tackle genetic mutations in human cells may help in treating some forms of Alzheimer's disease and other disorders caused by certain genetic mutations.

According to biologist Samit Adhya at the Indian Institute of Chemical Biology (IICB) in Calcutta and his colleagues, a protein found inside the leishmania parasite, when transplanted into human cells, can correct the effects of mutations in mitochondria, the powerhouses of cells.

Their experiments, reported in the recent issue of the US journal Science, have opened new possibility of exploiting the parasite's protein to treat a number of human diseases that are caused by mutations in human mitochondria.

"We're still a great distance away from human applications," Adhya, however, warned. "But we've established a proof of principle for something that might one day emerge as a novel strategy to tackle such mitochondria–related illnesses."

The research team picked a protein called RIC that the parasite uses to import genetic material called t–RNA — used in the manufacture of proteins — into its mitochondria.

The mitochondria of the leishmania parasites are devoid of t–RNA. Instead, the parasite has evolved RIC to draw t–RNA floating outside the mitochondria and transport them inside.

In their studies, the researchers added RIC into human cells in a laboratory dish. Not only did the RIC protein move inside the human cells, it also parked itself on the surface of human mitochondria and attracted and guided t–RNA inside — performing the same function for human mitochondria that it does for leishmania mitochondria.

In many human diseases such as late–onset Alzheimer's disease, maternally inherited diabetes and deafness, and some neuro–degenerative diseases, mitochondria have mutations in genes for t–RNA.

The new studies point to an alternative route to help human mitochondria regain lost t–RNA functions — with help from the leishmania parasite protein.

The IICB scientists said their findings also reveal a new facet of parasites, micro–organisms that cause a number of diseases from malaria to leishmaniasis to sleeping sickness.

"The general notion, even within scientific circles, is that parasites are evil. Most research is focused on how parasites evade the immune system, how they infect cells and how they cause disease in humans. We've shown that some components of parasite biology may also help us fight some diseases," Adhya said.