A report has found that a synthetic peptide disrupts the inflammation which occurs in nephritis, helping the kidneys to recover and maintain their important functions.
Acute or chronic nephritis, which affects both kidneys and the million filtering units in each, can be caused by a serious infection or injury, or diseases like uncontrolled hypertension and diabetes.
Particularly in cases of chronic nephritis, patients often have kidney failure and require dialysis.
Dr. Michael Madaio, nephrologist, chair emeritus of the Medical College of Georgia, Augusta University the study’s co-corresponding author, said: “We’ve been looking for a great way to treat this. In theory, this could take the place of the anti-inflammatory effect of steroids. That would be great.”
The synthetic peptide
The TIP peptide Lucas developed is a synthetic version of the tip of tumour necrosis factor (TNF). TNF is known to target cancer, but is also a primary instigator of destructive inflammation in nephritis.
The researchers watched a mouse model of nephritis. Immune cells arrived in response to a toxin attack on the kidney, which in turn generated a lot of TNF. TNF then activated two main inflammation-promoting pathways in the endothelial cells that line the million kidney filtering units (glomeruli) and the podocytes, the cells that wrap around the capillaries of the filtering units.
TNF also decreased production of things like nitric oxide, that could help the kidneys recover, and prostaglandin E2, which can suppress the immune response and inflammation.
Dr Rudolf Lucas, vascular biologist in the Vascular Biology Center at the Medical College of Georgia at Augusta University, said: “This is how high levels of TNF are bad for us, and the consequence of this is now you get an increased protein in your urine and you will get increased renal inflammation and that is not what you want.”
The researchers found that their TIP peptide delivered directly to the kidneys reduced inflammation and decreased blood pressure, despite a high-salt diet, and did not interfere with the infection-fighting role of TNF.
Reversing kidney inflammation from nephritis
Madaio explained: “We showed that it reversed inflammation in the kidney during the course of nephritis. We showed that it was effective and that it was a local effect within the kidney itself.”