17 Oct Diabetes: Type I Diabetics Still Make Small Amounts of Insulin
MedicalResearch.com Interview with:
Richard A. Oram, BMBCh, BA(hons), MRCP
NIHR Exeter Clinical Research Facility
University of Exeter Medical School, Barrack Road, Exeter, UK
MedicalResearch.com: What are the main findings of the study?
Answer: Historically people with Type 1 diabetes were thought to progress to make absolutely none of their own insulin. Modern assays allow us to measure very low levels of insulin, and using these we can find very tiny amounts of insulin production in most people with Type 1 diabetes even if they have had the disease for many years.
MedicalResearch.com: Were any of the findings unexpected?
Answer: The above finding fits with autopsy data that show a large proportion of people with Type 1 Diabetes have occasional beta cells visible within their pancreases, but it was still a surprise to find quite so many people, so far from diagnosis were still making these tiny amounts of insulin.
We wanted to demonstrate that the low levels were not “background noise” from the assay so were very happy and surprised that the results of the stimulation test were so clear: When comparing fasting and post-meal samples, we felt the fact that C-peptide either went up (80% of the time) or stayed the same but never went down, proved that the C-peptide levels detected truly represented functional beta cells.
MedicalResearch.com: What should clinicians and patients take away from your report?
Answer: This is an exciting result that improves our knowledge of the biology of Type 1 diabetes, it also raises questions about whether very low levels of insulin can be of any clinical benefit (to complications and hypoglyaemia).
Being able to compare who keeps endogenous insulin to the people who do not will enable us to further study the biology of Type 1 diabetes. This is very important for the long-term goal of developing a way to prevent Type 1 diabetes, halt beta cell destruction or ultimately find a cure.
It is important to remember this is a “proof of concept” study with a modest sample size. It should not change day-to-day management of people with Type 1 diabetes.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Answer: It would be great to replicate these findings in a larger group – this is something we are currently working on. (We used a urine C-peptide measurement as well as a blood in this study specifically because the urine method for assessing C-peptide can be posted from home and may therefore be logistically easier to use for large population based studies. We have a follow up study of ~1000 people and we are currently doing the data analysis and hope to present this work soon…..)
A key question is whether the very tiny levels that we detected could affect the risk of complications or hypoglycaemia, this would be of clinical importance and would also impact on the work of groups trying to restore beta cell function or prevent destruction using immunotherapy.
We do not know for sure whether the cells that remain are cells that have regenerated of are just resistant to immune attack, it would be really nice to be able to answer this…
The majority of patients with long-duration type 1 diabetes are insulin microsecretors and have functioning beta cells
Richard A. Oram, Angus G. Jones, Rachel E. J. Besser, Bridget A. Knight,
Beverley M. Shields, Richard J. Brown, Andrew T. Hattersley, Timothy J. McDonald
Received: 6 August 2013 /Accepted: 9 September 2013