Proteomic and metabolomic approaches to diagnose diabetes and pre-diabetes.

More than 5 million adults in the United States have undiagnosed type 2 diabetes mellitus, and another 38 million with pre-diabetes are at increased risk for developing diabetes. The lack of a simple and reliable way to detect diabetes and pre-diabetes has hindered identification of these individuals and provision of effective therapies. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) encourages the application of proteomic and other novel technologies to develop new diagnostic tests and/or to identify new biomarkers for the diagnosis of pre-diabetes and/or diabetes that do not require fasting or glucose administration.

Diabetes is a metabolic disease characterized by hyperglycemia that in 2002 affected nearly 9% of U.S. adults. More than 90% of the people with diabetes have type 2 diabetes. The symptoms of type 2 diabetes develop gradually. Some people have no symptoms until after they develop complications, which could have been prevented or delayed with early diagnosis and effective treatment. Additionally, 38 million U.S. adults aged 40-74 have pre-diabetes. Pre-diabetes is defined as impaired fasting glucose or impaired glucose tolerance (http://www.diabetes.org/diabetes-prevention/ pre-diabetes.jsp). These individuals have glucose levels above normal but below the level needed for diagnosis of diabetes. They are at increased risk of cardiovascular disease compared to those with normal glucose tolerance, and are at substantial risk for developing diabetes.

Clinical trials have demonstrated effective interventions for preventing or delaying complications in those with diabetes and for preventing or delaying onset of diabetes in those with pre-diabetes. However, millions of Americans are not receiving effective therapy, in part due to the limitations of current methods of diagnosing diabetes and pre-diabetes. The oral glucose tolerance test (OGTT)--the gold standard for diagnosis of diabetes and pre-diabetes--is inconvenient, requires fasting, and is not highly reproducible. The fasting blood glucose is less burdensome but much less sensitive, particularly in older Americans, who have the highest prevalence of diabetes and pre-diabetes. The quantitation of hemoglobin A1c (a glycated form of hemoglobin) from blood has been widely used as a test for assessing the adequacy of glycemic control and risk of complications in diabetic patients, but this test is not sufficiently sensitive to detect the range of glucose values typically seen in pre-diabetes or new-onset type 2 diabetes. Furthermore, there are many variants of hemoglobin present in blood, particularly in minority populations that are disproportionately affected by diabetes, and this adds additional uncertainty to the use of this test.

A simplified, less burdensome approach to the diagnosis of diabetes and pre-diabetes would facilitate increased recognition and improved care of these conditions. Many proteins and other blood components may be modified in individuals with elevated blood glucose. Identification of these molecules or of identifiable correlates of hyperglycemia would facilitate development of potential new laboratory tests for diagnosis of diabetes and pre-diabetes. With this initiative, we are encouraging scientists with expertise in proteomics and metabolomics to develop new tests to detect pre-diabetes and diabetes that correlate with the results of the OGTT but do not require fasting or administration of glucose.

Proteomic and metabolomic approaches have been successfully used for studying complex biological problems and for the identification of disease markers. Recent developments indicate that these technologies could be used or appropriately modified for developing new methods to diagnose diabetes and pre-diabetes. For example, mass spectrometry has been successfully used for the identification and quantitation of large numbers of proteins from plasma. Similar studies were performed for quantifying large numbers of metabolites. In some cases, fractionation prior to the mass spectrometric analysis was shown to be very effective for increasing the number of proteins and metabolites that could be identified, and further development in fractionation methodologies could perhaps be the key for the identification of novel biomarkers. The use of isotopically labeled reagents recently made many proteomic methodologies usable for quantitative studies, and further development of these reagents might also lead to a more comprehensive analysis of the sera proteome and possible identification of novel biomarkers.

This initiative solicits the application of proteomic and metabolomic technologies for the development of novel methodologies and/or the identification of new biomarkers for the diagnosis of pre-diabetes and type 2 diabetes that do not require fasting or glucose administration. To facilitate this effort, plasma from well-characterized individuals of diverse racial and ethnic backgrounds with normal glucose tolerance, impaired glucose tolerance, and type 2 diabetes will be made available to investigators for validation of potential new diagnostic tests.

The novel diagnostic test could ultimately be used in place of the OGTT, if adequately validated, or for the identification of high-risk individuals who should undergo testing for diabetes and pre-diabetes using a more functional assay such as the OGTT. Focused deployment of the OGTT in appropriately selected individuals would reduce costs, limit burden, and improve the yield of diagnostic testing for diabetes and pre-diabetes.

This special-emphasis program announcement (PAR) will use the NIH Exploratory/Development Research Grant (R21) combined with the Exploratory/ Development Research Grant Phase 2 (R33). The R33 is an NIH grant mechanism that provides a second phase for the support of innovative exploratory and developmental research initiated under the R21 mechanism. The transition of the R21 to the R33 phase will be expedited and is dependent on completion of negotiated milestones. As an applicant, you will be solely responsible for planning, directing, and executing the proposed project. This PAR is a one-time solicitation. Future unsolicited, competing-continuation applications based on this project will have to be submitted using a standard R01 or R21 mechanism, will compete with all investigator-initiated applications, and will be reviewed according to the customary peer-review procedures.

To be considered for the transition to the R33 phase, the applicant must show that he/she has identified differences between the pre-diabetes, diabetes, and normal patient samples provided by the NIDDK for the R21 phase (i.e., applicant must have identified at least one potential biomarker for pre-diabetes and/or diabetes). These differences should be determined in a reproducible and quantitative way and with a throughput that shows promise for translation to a clinical setting. In addition, the investigator can include in the proposal the use of samples from other clinical studies for optimizing or further validating the methodology.

For the purpose of assessing research progress and facilitating interaction between the 4-5 funded principal investigators, a workshop will be held in May/June 2006 in Bethesda, Maryland. All funded principal investigators are required to attend, and collaborators are encouraged to participate. Funds for attending this meeting should be included in the budget proposal.

This PAR uses just-in-time concepts. It also uses the modular as well as the nonmodular budgeting formats (see http://grants.nih.gov/grants/ funding/modular/modular.htm). Specifically, if you are submitting an application with direct costs in each year of $250,000 or less, use the modular format. Otherwise, follow the instructions for nonmodular research grant applications. This program does not require cost sharing as defined in the current NIH Grants Policy Statement at http://odoerdb2. od.nih.gov/gmac/nihgps_2003/index.htm.

The NIDDK intends to commit approximately $1 million in direct costs for fiscal year 2005 to fund 4-5 new grants in response to this PAR. An applicant may request a project period of 2 years for the R21 phase and 3 years for the R33 phase. The R21 phase may not exceed $250,000 in direct costs per year. The R21 budgets can exceed this cap to accommodate facilities and administrative costs to subcontracts to the project, in which case a nonmodular budget format must be used. The R33 application has a budgetary limit of $500,000 in direct costs for each year. Awards pursuant to this PAR are contingent upon the availability of funds and the receipt of a sufficient number of meritorious applications.

Applications must be prepared using the PHS 398 research grant application instructions and forms (rev. 5/2001). Applications must have a Dun and Bradstreet Data Universal Numbering System (DUNS) number as the Universal Identifier when applying for federal grants or cooperative agreements. The DUNS number can be obtained by calling 1-866-705-5711 or through the website at http://www. dunandbradstreet.com/. The PHS 398 document is available at http://grants.nih.gov/grants/funding/ phs398/phs398.html in an interactive format. For further assistance, contact GrantsInfo, 301-435-0714, email: [e-mail].

Letters of intent are due 18 June 2004, with applications due 20 July 2004. The anticipated award date is 1 April 2005. Applications that are not funded in the competition described in this PAR may be resubmitted as new investigator-initiated applications using the standard receipt dates for new applications described in the instructions to the PHS 398 application. For more information on this PAR, see http://grants.nih.gov/grants/guide/pa-files/ PAR-04-076.html

Contact: Direct questions about scientific and research issues to Salvatore Sechi, Division of Diabetes, Endocrinology, and Metabolic Diseases, NIDDK, 6707 Democracy Blvd, Rm 611, Bethesda, MD 20892-5460 USA, 301-594-8814, fax: [phone], e-mail: [e-mail]; direct questions about peer review issues to Francisco O. Calvo, Division of Extramural Activities, NIDDK, 6707 Democracy Blvd, Rm 752, Bethesda, MD 20892-5452 USA, 301-594-8897, fax: [phone], e-mail: [e-mail]; direct questions about financial and grants management matters to Kathleen Shino, Grants Management Branch, NIDDK, 6707 Democracy Blvd, Rm 708, Bethesda, MD 20892-5460 USA, 301-594-8869, fax: [phone], e-mail: [e-mail]. Reference: PA No. PAR-04-076