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The SAGE Encyclopedia of Stem Cell Research


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Diabetes, Endocrinology, and Metabolic Diseases at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), discussed, not long ago, the NIDDK’s research initiatives of setting up and implementing clinical trials for diabetes that would be sponsored by the government and that are “not currently pursued by drug companies.”

      One of the successes of the National Institutes of Health (NIH)/NIDDK multicenter trials pointed to by Fradkin, is the success in recruiting ethnically heterogeneous populations. The government-sponsored initiative includes about 45 percent of minority groups. The study looked at the incidence rates of diabetes based on three factors: the use of metformin, the presence of a placebo, and lifestyle intervention. The benefits of metformin and lifestyle interventions in the reduction of the incidence of type 2 diabetes were clear across all of the ethnic groups under study. This fact alone proved to be key, as it indicates that type 2 diabetes affects minority populations in a disproportionate manner compared to other racial groups.

      An additional positive outcome that resulted from this study has been that, in addition to the inclusion of diverse ethnic groups, trials sponsored by the government have succeeded in classifying diabetic patients by phenotype. Such an unexpected finding has had important impact on the development of type 1 diabetes trials. The study also succeeded in creating some phenotyping following pharmacogenomics analyses. The results revealed that even for people with higher genetic risk for type 2 diabetes, lifestyle interventions may succeed in reducing their level of risk. This was described by the community of scientists as “a powerful result” indicating that genetics is far from being synonymous with destiny when it comes to developing type 2 diabetes.

      NIDDK: A New Model for Clinical Trial Collaboration

      Given the prevalence of diabetes in older adults and its constant increase in children, the expanded time course of the disease, and the costs associated with it, Fradkin believes that “diabetes is a good candidate for collaboration between NIH and the Centers for Medicare and Medicaid Services (CMS). Very few of the practices Medicare pays for have been rigorously examined in [randomized clinical trials] RCTs. Given NIDDK’s track record in conducting paradigm-shifting diabetes trials in diverse populations, conducting clinical trials in the Medicare population could offer an opportunity for cost savings.” Such collaboration would work in that NIH/NIDDK and CMS would share the costs related to research and clinical care, opening a new era of collaboration that could potentially benefit diabetic patients.

      TrialNet: A Network Strategy for Type 1 Diabetes Trials

      Another new venture that could be beneficial for diabetic patients in the long term is the establishment of TrialNet. Funded jointly by the Juvenile Diabetes Research Foundation International (JDRF), the NIH, and the American Diabetes Association (ADA), and approved by Congress, TrialNet is an international network of researchers and scientists whose objective is to explore new ways to delay, prevent, and potentially reverse the progression of type 1 diabetes. TrialNet researchers come from 18 clinical centers in Canada, the United Kingdom, Finland, Italy, New Zealand, Germany, and the United States, and more than 150 medical centers and physician offices.

      New Treatment Pushed Forward by the Pharmaceutical Industry

      While government initiatives for the fight against diabetes are emerging and flourishing, America’s biopharmaceutical research companies also continue to explore various strategies to combat diabetes and its related conditions. Some potential new treatments from the 180 existing medications in development today include enhancing the regeneration of insulin-producing cells (islets) and stimulating the formation of cells capable of generating insulin, a potential state-of-the-art treatment for type 1 diabetes. The treatment would consist of a human peptide made up of the bioactive part of a gene responsible for regenerating pancreatic islets.

      Leaps Forward on the Research Horizon

      The potential development of an effective vaccine or the use of stem cells to grow beta cells capable of making insulin are part of an array of promising lines of research intended to advance diabetes treatment. A number of novel devices are currently under way to better control blood sugar levels. In terms of vaccines, British scientists reported the existence of a well-known virus that could trigger type 1 diabetes by attacking insulin-making beta cells and triggering an infection. The underlying reasoning is that, if such process proves to be effective, it is highly possible that the individual’s immune response may not be able, in the end, to produce insulin. Based on this assumption, a vaccine with the ability to block infection by a virus might also be able to prevent diabetes from developing. In the United States, some Harvard University researchers have suggested that a widely used tuberculosis vaccine could treat type 1 diabetes by acting on the person’s immune response to kill beta cells. In current studies, type 1 diabetic mice started to produce insulin following treatment with the vaccine.

      As for glucagon, which is produced in the pancreas and released when blood sugar levels are too low, a recent study stated that “suppressing the action of glucagon made insulin unnecessary to control blood sugar levels.” These results could suggest that if the action of glucagon is blocked, normal glucose tolerance might be restored.

      Morenike Trenou

       Independent Scholar

      See Also: Adult Stem Cells: Overview; Clinical Trials Outside the United States; Hematopoietic Transplantation: Gene Therapy.

      Further Readings

      Cooke, D. W. and L. Plotnick. “Type 1 Diabetes Mellitus in Pediatrics.” Pediatric Review, v.29/11 (2008).

      Emerging Risk Factors Collaboration. “Diabetes Mellitus, Fasting Blood Glucose Concentration, and Risk of Vascular Disease: A Collaborative Meta-Analysis of 102 Prospective Studies.” Lancet, v.375/9733 (2010).

      International Diabetes Federation. http://www.idf.org (Accessed April 2014).

      Kitabchi, A. E., G. E. Umpierrez, J. M. Miles, and J. N. Fisher. “Hyperglycemic Crises in Adult Patients With Diabetes.” Diabetes Care, v.32/7 (July 2009).

      Melmed, Shlomo, et al. Williams Textbook of Endocrinology, 12th ed. Philadelphia: Elsevier/Saunders, 2011.

      Nathan, D. M., P. A. Cleary, J. Y. Backlund, S. M. Genuth, et al. Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study Research Group (December 2005). “Intensive Diabetes Treatment and Cardiovascular Disease in Patients With Type 1 Diabetes.” New England Journal of Medicine, v.353/25 (2005).

      Shoback, David G. and Dolores Gardner. Greenspan’s Basic & Clinical Endocrinology, 9th ed. New York: McGraw-Hill Medical, 2011.

      Vos, T., A. D. Flaxman, et al. “Years Lived With Disability (YLDs) for 1160 Sequelae of 289 Diseases and Injuries 1990–2010: A Systematic Analysis for the Global Burden of Disease Study 2010.” Lancet, v.380/9859 (December 15, 2012).

      World Health Organization. http://www.who.int/diabetes/en (Accessed April 2014).

      Clinical Trials, U.S.: Eye Conditions

      Clinical Trials, U.S.: Eye Conditions

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      Clinical Trials, U.S.: Eye Conditions

      Retinopathies pertain to vascular conditions that involve the eye, often leading to blindness. Research on cell-based therapy has resulted in the identification of self-renewing cells that could be utilized to replace lost cells of the retina, including associated vascular and neuronal tissues. Interestingly, there are at least four types of stem cells that could be employed for cell-based therapy of eye conditions.