News & Research

    University of Mississippi Medical Center, Jackson, Mississippi

Protective effects of C-peptide in diabetic nephropathy

General Research Subject: Both Type 1 And Type 2 Diabetes

Focus: Complications, Complications\Neuropathy

Type of Grant: Basic Science

Project Start Date: January 1, 2013

Project End Date: December 31, 2015

Research Description

C-peptide is a short protein that structurally connects the two chains of the inactive insulin molecule called proinsulin. For a long time, this was all C-peptide was thought to do; however, recent studies have shown that C-peptide may be beneficial in the treatment of organ complications associated with type 1 diabetes, including diabetic kidney disease. Specifically, in our preliminary studies we have found that treatment with C-peptide in an animal model of kidney disease associated with type 1 diabetes prevents the severity of kidney injury. Interestingly, while it protects the kidney from diabetes-induced injury it also reduces blood sugar levels, suggesting that its beneficial effects may be achieved through regulation of sugar levels.

Even if this were the case, treatment with C-peptide would have tremendous clinical use as regulating blood sugar levels is an enormous challenge for patients with type 1 diabetes. However, we have strong reasons to believe that C-peptide may also have direct protective effects on the kidney independent of blood sugar regulation. We say this as we find that in non-diabetic rats that have kidney disease without the diabetes, C-peptide is beneficial without altering blood sugar levels. However, whether C-peptide is beneficial to the kidney after prolonged diabetes that is associated with severe kidney disease is unknown. This application will examine the mechanisms by which C-peptide treatment protects the kidney in prolonged type 1 diabetes.

Research Profile

What area of diabetes research does your project cover? What role will this particular project play in preventing, treating and curing diabetes?

C-peptide is a short protein that structurally connects the two chains of the inactive insulin molecule called proinsulin. For a long time, this was all C-peptide was thought to do; however, recent studies have shown that C-peptide may be beneficial in the treatment of organ complications associated with type 1 diabetes, including diabetic kidney disease. Our studies are showing that treatment with C-peptide in an animal model of kidney disease associated with type 1 diabetes prevents the severity of kidney injury. Interestingly, while it protects the kidney from diabetes-induced injury it also reduces blood sugar levels, suggesting that its beneficial effects may be achieved through regulation of sugar levels. However, we have strong reasons to believe that C-peptide may also have direct protective effects on the kidney independent of blood sugar regulation. This project will examine the mechanisms by which C-peptide treatment protects the kidney in prolonged type 1 diabetes.

If a person with diabetes were to ask you how your project will help them in the future, how would you respond?

We anticipate that treatment with C-peptide will result in a decrease in the amount of protein in the urine and a decrease in kidney injury associated with diabetic kidney disease, independent of blood sugar lowering. We also hope that we may be able to translate this knowledge on treatment of other diabetes-related organ complications. In addition, treatment with C-peptide along with insulin may prove beneficial in regulating glucose levels, which could have tremendous clinical use as regulating blood sugar levels is an enormous challenge for patients with type 1 diabetes.

Why is it important for you, personally, to become involved in diabetes research? What role will this award play in your efforts?

The personal reasons why many scientists get involved with diabetes research are not difficult to understand. The incidence of diabetes in the Western world is so high that virtually everyone has some one either in their own family or amongst their friends who is suffering from the disease. I would be no exception to this rule with a family history of diabetes and end-organ complications. However, the determining factor for me was the presence of strong gender differences in the incidence of the diabetes not apparent in many other diseases. It always intrigued me that women are predisposed to certain types of disease more so than men and although diabetes has been amongst these diseases, research into gender differences in diabetes has not been investigated.

The Research Award from the ADA will enable me to continue and expand my studies into finding novel treatments for diabetic kidney complications.

In what direction do you see the future of diabetes research going?

Despite the successful application of existing drugs in managing diabetic kidney complications, the complete prevention of the occurrence and treatment of the disease has still not been achieved, especially in women. This suggests that our understanding of the disease process is still quite limited.

Kidney disease is often associated with prolonged diabetes and therefore, our efforts need to be targeted towards understanding how the kidney sees and reacts to the factors that govern the pathology of the disease. Better understanding of the factors involved in the development of diabetic kidney disease may lead to either novel therapeutic treatments, but more importantly may contribute to our ability to prevent the onset of the disease.