PHILADELPHIA, Oct. 14 (UPI) -- A deficiency in neuropilin 2 receptors may result in prolonged fluid buildup after inflammation, researchers found in a study on edema and lymphedema.
Scientists say the new study opens the door for developing new treatments for lymphedema and edema, a disease characterized by excessive inflammation beneath the skin and in the cavities of the body. Patients living with the disease can experience severe pain and swelling.
The research team, led by Harvard Medical School assistant professor Diane Bielenberg, aimed to build on previous studies that showed inhibited vascular endothelial growth factor receptors demonstrate reduced blood vessel permeability after inflammation. In the new study, the investigators observed the reverse effect with neuropilin 2 knockout mice.
"We expected to see less permeability after inflammation in neuropilin 2 (Nrp2) knockout mice," Bielenberg explained in a press release, noting inflammation led to heightened edema.
The neuropilin 2 deficient mice demonstrated prominent ear swelling. Fluid retention was measured to be 2.5 times higher in the experimental group than the control group. The swelling in mice that were not administered an inflammation-causing substance receded within two days. By contrast, swelling in experimental group lasted for over 10 days.
Investigators tied the lack of superficial lymphatic capillary plexus in Nrp2-deficient mice to the increased inflammation. The findings were published in The American Journal of Pathology.