Growth factor may protect blood vessels from diabetic damage

Researchers from Schepens Eye Research Institute have found that a slight increase in transforming growth factor beta (TGF-β) protects retinal blood vessels from damage in a rat model of diabetic retinopathy.

TGF-β is a cytokine that regulates a variety of cellular functions including proliferation, differentiation and immune response.

Because the team previously found that TGF-β levels are elevated in diabetic retinal blood vessels, they initially hypothesized that the signaling molecule was responsible for the development of diabetic retinopathy. The authors were surprised to learn that inhibition of the excess TGF-β with oral medication– while preserving the baseline expression- did not protect against disease progression but rather resulted in deterioration to the rat blood vessels.

"We found that increased TGF-β is really defending the vessels in the retina," said senior author Mara Lorenzi, MD. "When we took away the small increase in TGF-β, we saw significant damage to the retinal vessels in animals with diabetes. Based on this finding, we'd now like to know if a little extra TGF-β will help protect the retinal vessels in patients with diabetes."

The authors suggest that future therapies that lead to upregulation of TGF-β could help delay or prevent DR, and advise caution when prescribing TGF-β blocking drugs to diabetic patients.