From the JDRF and UC San Francisco:
JDRF-funded researchers have identified a protein on immune T cells that triggers type 1 diabetes in mice when it interacts with another protein found in cells of the pancreas. The scientists report that blocking the interaction prevents the disease without compromising normal immune defenses or causing measurable side effects.
The finding points to a possible strategy for preventing type 1 diabetes in humans, since the mouse T cell protein has a counterpart in the human immune system. The study, led by Jeffrey Bluestone, Ph.D., and Lewis Lanier, Ph.D., of the University of California, San Francisco (UCSF), was published in the June issue of the journal Immunity. The research was funded as part of the JDRF Center for Islet Transplantation at University of California, San Francisco/University of Minnesota
The T cell protein, called NKG2D, is a receptor on the surface of certain T cells called CD8 lymphocytes. Scientists became interested in NKG2D after observing the development of diabetes in nonobese diabetic (NOD) mice, the animal model for type 1 diabetes. In NOD mice, some CD8 T cells invade the pancreas when the animals are only three weeks old. These invading T cells, unlike most others, express the NKG2D receptor. Ten to 20 weeks later, the animals develop the disease.
The other protein of interest, called RAE-1, has been found on cells infected by bacteria or viruses. Normally, the RAE-1 protein binds to NKG2D, alerting CD8 T cells and other immune system molecules to attack and eliminate the pathogen. By this mechanism, the body ensures that foreign, or “non-self” material is flagged and destroyed.
The UCSF researchers were surprised to find that RAE-1 also is present in the pancreas of nonobese diabetic (NOD) mice. This presence of RAE-1 in the pancreatic cells, and the expression of NKG2D by the invading T cells, suggested than an interaction between the two proteins may play a role in type 1 diabetes.
When the scientists used antibodies to prevent RAE-1 from binding its receptor (NKG2D) on the CD8 lymphocytes, the mice were completely protected from the disease. (The effect is like plugging a keyhole so that even the correct key won’t turn the ignition). “You don’t need a calculator to tell the treatment group from the placebo group. It’s 100 percent effective,” Dr. Lanier, said in a press statement.
The researchers expect that a “humanized” antibody to human NKG2D, working in a similar manner, could provide an effective type 1 diabetes treatment in people. The finding is important, because unlike other treatments reported in NOD mice, this therapy was effective even when given relatively late in disease progression.
Friday, August 13, 2004
Sunday, August 08, 2004
Insulin Pump Beats Shots for Young Diabetics
From Reuters Health:
NEW YORK - Continuous insulin infusion delivered by a portable pump is more effective than multiple daily injections of insulin in controlling blood sugar levels in young people with type 1 diabetes, according to a new study.
Moreover, most patients chose to continue with or switch to insulin pumps after the study was over, Elizabeth A. Doyle and colleagues from the Yale University School of Medicine in New Haven report in the medical journal Diabetes Care.
The researchers randomly assigned 32 patients aged 8 to 21 to treatment with pump-delivered continuous subcutaneous insulin infusion (CSII) or to once-daily long-acting insulin (glargine) plus fast-acting insulin injections before meals and snacks, for 16 weeks.
Blood levels of hemoglobin A1c - an indicator of long-term blood glucose control - did not change in the multi-injection group, but dropped to target levels in the insulin pump patients.
The researchers point out that glargine cannot be mixed with rapid-acting insulin, so therapy with this insulin analog requires patients to give themselves injections with fast-acting insulin before meals and large snacks. The need for multiple daily injections can make compliance difficult, they add.
In fact, at the close of the study, 14 of the 16 patients on CSII chose to continue using the infusion pumps, while 12 of the 16 patients on multiple daily injections switched to CSII.
The team calls for further studies but concludes that "in the context of a short-term randomized clinical trial, we observed a considerably greater improvement in hemoglobin A1c levels with CSII than with glargine. It should be noted, however, that no single approach to treatment is ideal for every patient."
SOURCE: Diabetes Care, July 2004.
NEW YORK - Continuous insulin infusion delivered by a portable pump is more effective than multiple daily injections of insulin in controlling blood sugar levels in young people with type 1 diabetes, according to a new study.
Moreover, most patients chose to continue with or switch to insulin pumps after the study was over, Elizabeth A. Doyle and colleagues from the Yale University School of Medicine in New Haven report in the medical journal Diabetes Care.
The researchers randomly assigned 32 patients aged 8 to 21 to treatment with pump-delivered continuous subcutaneous insulin infusion (CSII) or to once-daily long-acting insulin (glargine) plus fast-acting insulin injections before meals and snacks, for 16 weeks.
Blood levels of hemoglobin A1c - an indicator of long-term blood glucose control - did not change in the multi-injection group, but dropped to target levels in the insulin pump patients.
The researchers point out that glargine cannot be mixed with rapid-acting insulin, so therapy with this insulin analog requires patients to give themselves injections with fast-acting insulin before meals and large snacks. The need for multiple daily injections can make compliance difficult, they add.
In fact, at the close of the study, 14 of the 16 patients on CSII chose to continue using the infusion pumps, while 12 of the 16 patients on multiple daily injections switched to CSII.
The team calls for further studies but concludes that "in the context of a short-term randomized clinical trial, we observed a considerably greater improvement in hemoglobin A1c levels with CSII than with glargine. It should be noted, however, that no single approach to treatment is ideal for every patient."
SOURCE: Diabetes Care, July 2004.
Eating Disturbances More Common in Diabetic Girls
From Reuters:
NEW YORK - Preteen and early teenage girls with type 1 diabetes experience eating disturbances more often than girls without the condition, according to Canadian researchers.
As reported in the journal Diabetes Care, Dr. Patricia Colton and colleagues, from the University of Toronto, compared the rate of eating disturbances in 101 diabetic and 303 non-diabetic girls.
The subjects completed the Children's Eating Disorder Examination interview, and the investigators assessed socioeconomic status, body weight, and various diabetes-related factors.
The same proportion of diabetic and nondiabetic girls - 16 percent - reported at least one disturbed eating episode in the previous month. However, 8 percent of diabetic girls reported currently engaging in at least two disturbed eating behaviors compared with just 1 percent of non-diabetic girls.
Eleven percent of girls with diabetes reported dieting in the previous month, not that much different from the rate in the non-diabetic group - 15 percent. On the other hand, 10 percent of diabetic girls took part in excessive exercise for weight control compared with only 1 percent of girls without diabetes.
Binge eating was also more common among diabetic girls (3 percent) than among non-diabetic girls (0.3 percent).
Given these findings, the researchers conclude that eating disorder "screening and prevention programs for (diabetic girls) should begin in the preteen years."
SOURCE: Diabetes Care, July 2004.
NEW YORK - Preteen and early teenage girls with type 1 diabetes experience eating disturbances more often than girls without the condition, according to Canadian researchers.
As reported in the journal Diabetes Care, Dr. Patricia Colton and colleagues, from the University of Toronto, compared the rate of eating disturbances in 101 diabetic and 303 non-diabetic girls.
The subjects completed the Children's Eating Disorder Examination interview, and the investigators assessed socioeconomic status, body weight, and various diabetes-related factors.
The same proportion of diabetic and nondiabetic girls - 16 percent - reported at least one disturbed eating episode in the previous month. However, 8 percent of diabetic girls reported currently engaging in at least two disturbed eating behaviors compared with just 1 percent of non-diabetic girls.
Eleven percent of girls with diabetes reported dieting in the previous month, not that much different from the rate in the non-diabetic group - 15 percent. On the other hand, 10 percent of diabetic girls took part in excessive exercise for weight control compared with only 1 percent of girls without diabetes.
Binge eating was also more common among diabetic girls (3 percent) than among non-diabetic girls (0.3 percent).
Given these findings, the researchers conclude that eating disorder "screening and prevention programs for (diabetic girls) should begin in the preteen years."
SOURCE: Diabetes Care, July 2004.
Saturday, August 07, 2004
Heart Enlargement Appears Early in Type 1 Diabetes Patients
From Reuters Health
NEW YORK - Children and adolescents with insulin-dependent (type 1) diabetes, particularly girls, show early signs of changes in the heart, a research team in Belgium has found.
Dr. Bert E. Suys at University Hospital of Antwerp and colleagues used ultrasound to examine the hearts of 80 young people with diabetes and 52 age-matched control subjects.
As reported in the medical journal Diabetes Care, the wall of the left ventricle, the main pumping chamber of the heart, was thicker in girls with diabetes than in the non-diabetic group. The hearts of diabetic girls also showed delayed relaxation between heartbeats.
For boys, the only difference between those with and without diabetes was in the relaxation time.
Suys and his associates theorize that, in children, "perhaps already a small increase in blood glucose is sufficient to initiate changes in the cardiovascular system," thus underscoring the importance of long-term blood sugar control.
Patients with diabetes may benefit from drugs like ACE inhibitors and beta-blockers that are used to treat heart failure, the researchers add, but only further research will clarify this issue.
NEW YORK - Children and adolescents with insulin-dependent (type 1) diabetes, particularly girls, show early signs of changes in the heart, a research team in Belgium has found.
Dr. Bert E. Suys at University Hospital of Antwerp and colleagues used ultrasound to examine the hearts of 80 young people with diabetes and 52 age-matched control subjects.
As reported in the medical journal Diabetes Care, the wall of the left ventricle, the main pumping chamber of the heart, was thicker in girls with diabetes than in the non-diabetic group. The hearts of diabetic girls also showed delayed relaxation between heartbeats.
For boys, the only difference between those with and without diabetes was in the relaxation time.
Suys and his associates theorize that, in children, "perhaps already a small increase in blood glucose is sufficient to initiate changes in the cardiovascular system," thus underscoring the importance of long-term blood sugar control.
Patients with diabetes may benefit from drugs like ACE inhibitors and beta-blockers that are used to treat heart failure, the researchers add, but only further research will clarify this issue.
Scads of research
The JDRF is all about research. It's right there in the organization's name.
The leadership has a profound belief that cures for Type I diabetes can and will be found through research. It is the driving principle behind everything the organization does.
In the coming weeks, you will discover in this space some of the latest results of that research from around the globe. This offering is not meant to be comprehensive, but rather an updated sampler of the tremendous stides being made with the money groups like Team Shelby raise.
The leadership has a profound belief that cures for Type I diabetes can and will be found through research. It is the driving principle behind everything the organization does.
In the coming weeks, you will discover in this space some of the latest results of that research from around the globe. This offering is not meant to be comprehensive, but rather an updated sampler of the tremendous stides being made with the money groups like Team Shelby raise.
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