Researchers Mohan Rema (left) and Muthuswamy Balasubramanyam.
Researchers have found that curcumin, alongside its very many other uses, can block a key biological pathway needed for development of proliferative diabetic retinopathy, an eye complication among diabetics that leads to blindness if untreated1.
The study followed an epidemiology study2 in urban Chennai which showed that prevalence of diabetic retinopathy in Indians was lower than that among Europeans. Researchers suspected a dietary element behind this. "We suspected it was turmeric," says Mohan Rema, chief ophthalmologist and vice-president at Madras Diabetic Research Foundation and the corresponding author.
In diabetic retinopathy, abnormal new blood vessels grow in the retina of the eye due to a process called angiogenesis. These new vessels are thin and fragile and tend to bleed resulting in sudden and total loss of vision.
Angiogenesis involves growth of new blood vessels from pre-existing ones and is similar to wound healing. But it is also a key step helping tumor growth. Angiogenesis inhibitors (or anti-antigenic drugs) prevent the formation of new blood vessels so that the tumor cannot grow.
"In vitro experiments confirmed that curcumin, which shows anti-angiogenic effects against various cancers, may also inhibit the growth of new blood vessels in the retina," Rema said.
Turmeric, which is a major ingredient of Indian curries, also finds widespread use in traditional Indian, Chinese, and western herbal medicine.
