Medical Forum / Diseases and Disorders / Diabetes / October 2005
Oxidative stress-induced insulin resistance
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ironjustice@aol.com - 27 Oct 2005 02:42 GMT <<snip>> this association is not restricted to insulin resistance in type 2 diabetes, but is also evident in obese, nondiabetic individuals, and in those patients with the metabolic syndrome <<snip>>
The molecular basis for oxidative stress-induced insulin resistances. Evans JL, Maddux BA, Goldfine ID Antioxid Redox Signal. 2005 Jul-Aug ; 7(7-8): 1040-52
Reactive oxygen and nitrogen molecules have been typically viewed as the toxic by-products of metabolism. However, accumulating evidence has revealed that reactive species, including hydrogen peroxide, serve as signaling molecules that are involved in the regulation of cellular function. The chronic and/or increased production of these reactive molecules or a reduced capacity for their elimination, termed oxidative stress, can lead to abnormal changes in intracellular signaling and result in chronic inflammation and insulin resistance. Inflammation and oxidative stress have been linked to insulin resistance in vivo. Recent studies have found that this association is not restricted to insulin resistance in type 2 diabetes, but is also evident in obese, nondiabetic individuals, and in those patients with the metabolic syndrome. An increased concentration of reactive molecules triggers the activation of serine/threonine kinase cascades such as c-Jun N-terminal kinase, nuclear factor-kappaB, and others that in turn phosphorylate multiple targets, including the insulin receptor and the insulin receptor substrate (IRS) proteins. Increased serine phosphorylation of IRS reduces its ability to undergo tyrosine phosphorylation and may accelerate the degradation of IRS-1, offering an attractive explanation for the molecular basis of oxidative stress-induced insulin resistance. Consistent with this idea, studies with antioxidants such as vitamin E, alpha-lipoic acid, and N-acetylcysteine indicate a beneficial impact on insulin sensitivity, and offer the possibility for new treatment approaches for insulin resistance.
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Who loves ya. Tom
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outsor@citynet.net - 27 Oct 2005 01:52 GMT "revealed that reactive species, including hydrogen peroxide, serve as signaling molecules that are involved in the regulation of cellular function. The chronic and/or increased production of these reactive molecules or a reduced capacity for their elimination, termed oxidative stress, can lead to abnormal changes in intracellular signaling and result in chronic inflammation and insulin resistance."
Just so, they are normal parts of the regulation system. Thus in resistance it is a question as to why their output should exceed normal levels of these normal substances or their regulation be deminished to produce the same end.
What ever the answer, we know diabetes is not caused by iron.
ironjustice@aol.com - 27 Oct 2005 15:05 GMT <<snip>> Elevated iron stores were positively associated with serum ALT levels and metabolic syndrome in Korean postmenopausal women <<snip>>
Metabolism Volume 54, Issue 11 , November 2005, Pages 1510-1514 doi:10.1016/j.metabol.2005.05.018 Copyright 2005 Elsevier Inc. All rights reserved.
Association among serum ferritin, alanine aminotransferase levels, and metabolic syndrome in Korean postmenopausal women
K.M. Choi, K.W. Lee, H.Y. Kim, J.A. Seo, S.G. Kim, N.H. Kim, D.S. Choi and S.H. Baik,
Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University Guro Hospital, Seoul 152-050, Korea
Received 21 February 2005; accepted 11 May 2005. Available online 26 October 2005.
Abstract We examined the relationships among serum ferritin, alanine aminotransferase (ALT) levels, and cardiovascular risk factors of metabolic syndrome in Korean postmenopausal women. We conducted a cross-sectional study of 959 postmenopausal women without an apparent cause of liver disease. Metabolic syndrome was defined as the presence of at least 3 of the following: elevated blood pressure, low high-density lipoprotein cholesterol, elevated serum triglycerides, elevated plasma glucose, and abdominal obesity. Serum ferritin and ALT levels were found to be correlated (r = 0.374, P < .001) and to be associated with the components of metabolic syndrome. Subjects with metabolic syndrome showed significantly higher serum ferritin (74.7 2.0 vs 59.6 2.0 ng/mL, P < .001) and ALT levels (21.3 1.6 vs 18.7 1.5 IU/L, P < .001). Moreover, the greater the number of metabolic syndrome components present, the higher were the serum ferritin and ALT levels (P < .001). Multiple regression analysis showed that serum ALT levels are significantly associated with serum ferritin levels, waist circumference, fasting blood glucose, age, and white blood cell count (adjusted R2 = 0.147). Elevated iron stores were positively associated with serum ALT levels and metabolic syndrome in Korean postmenopausal women.
Corresponding author. Tel.: +82 2 818 6646; fax: +82 2 866 1643.
Metabolism Volume 54, Issue 11 , November 2005, Pages 1510-1514
Who loves ya. Tom
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outsor@citynet.net - 27 Oct 2005 16:09 GMT What do you think caused the higher iron levels to show up in association with the syndrome?
ironjustice@aol.com - 28 Oct 2005 14:41 GMT Well according to Dr. Jerome Sullivan .. the iron levels in women begin to mirror men / rise with the advent of menopause.
No longer 'protected' by their .. monthlies ..
The iron builds and causes diabetes ..
Pretty simple .. really ..
Do I need to explain it to you .. again ..?
OK ..
the iron levels in women begin to mirror men / rise with the advent of menopause.
No longer 'protected' by their .. monthlies ..
The iron builds and causes diabetes ..
Pretty simple .. really ..
Do I need to explain it to you .. again ..?
OK ..
the iron levels in women begin to mirror men / rise with the advent of menopause.
No longer 'protected' by their .. monthlies ..
The iron builds and causes diabetes ..
Pretty simple .. really ..
Do I need to explain it to you .. again ..?
Who loves ya. Tom
Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com
Man Is A Herbivore! http://pages.ivillage.com/ironjustice/manisaherbivore
DEAD PEOPLE WALKING http://pages.ivillage.com/ironjustice/deadpeoplewalking
outsor@citynet.net - 28 Oct 2005 20:00 GMT "Well according to Dr. Jerome Sullivan .. the iron levels in women begin to mirror men / rise with the advent of menopause.
No longer 'protected' by their .. monthlies .. The iron builds and causes diabetes ..
Pretty simple .. really .."
Simple indeed, so much so as to be ignored. If the above is a risk factor for diabetes can you show an increased risk for diabetes for either gender regardless of age? Let me save you some time, no. This is another counter example to the iron is the cause of all disease because people eat meat idea, here because women do have lower iron related to periods but risk of diabetes is not related. It takes only one counter example to toss an idea. When an idea fails to be supported in science, we turn from it to seek the truth elsewhere.
ironjustice@aol.com - 29 Oct 2005 12:18 GMT If the above is a risk factor for diabetes can you show an increased risk for diabetes for either gender regardless of age? Let me save you some time, no. <<
I believe I posted them already ..
http://tinyurl.com/dxxlf
Iron levels not much higher than that found in a vegetarian .. when lowered by bloodletting .. leads to decreased insulin resistance ..
Insulin resistance is a-s-s-o-c-i-a-t-e-d .. TO .. diabetes ..
That was a very easy one ..
Try harder ..
Who loves ya. Tom
Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com
Man Is A Herbivore! http://pages.ivillage.com/ironjustice/manisaherbivore
DEAD PEOPLE WALKING http://pages.ivillage.com/ironjustice/deadpeoplewalking
outsor@citynet.net - 29 Oct 2005 17:41 GMT Sorry, no cigar, but here is a coupon to kfc for you as consolation prize. I asked to have shown that women and men regardless of age have different risk levels for diabetes. The example you provided is par for the course, use a paint gun to connect dots to force a point that doesn't exist. The topic was the effect or not of menopause on risk for diabetes, not level of resistence based on lifestyle food choices. Reminding you again of the large population study for risk, bloodletting had no effect, bnot to mention the other counter examples to the iron causes all disease because people eat meat idea it contained, only one of which is enough to toss the idea.
ironjustice@aol.com - 30 Oct 2005 02:03 GMT The topic was the effect or not of menopause on risk for diabetes, not level of resistence based on lifestyle food choices. <<
Actually .. you asked a .. question .. and since you have some sort of memory loss .. "What do you think caused the higher iron levels to show up in association with the syndrome?"
And then you for some reason .. disregard my answer .. not even disregard .. outright say .. "you didn't answer the question" ..
When in FACT .. I .. did ..
Menopause .. no .. more .. blood loss .. Menopause .. no .. more .. blood loss .. Menopause .. no .. more .. blood loss .. Menopause .. no .. more .. blood loss .. Menopause .. no .. more .. blood loss .. Menopause .. no .. more .. blood loss ..
Get it ..?
No .. more .. 'natural bloodletting' ..
NOW .. iron builds .. due to LACK of .. bloodletting .. causing .. diabetes ..
Get it ..?
Who loves ya. Tom
Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com
Man Is A Herbivore! http://pages.ivillage.com/ironjustice/manisaherbivore
DEAD PEOPLE WALKING http://pages.ivillage.com/ironjustice/deadpeoplewalking
outsor@citynet.net - 31 Oct 2005 00:44 GMT Show us where risk of diabetes varies by gender by age. When women stop losing bllod routinely and have lower iron levels your theory would say risk for diabetes should change. Nope, and is only one couter example nail in the iron causes all disease because people eat meat idea. While many are available only one is required to toss it.
Sbharris[atsign]ix.netcom.com - 31 Oct 2005 06:14 GMT > Show us where risk of diabetes varies by gender by age. When women stop > losing bllod routinely and have lower iron levels your theory would say > risk for diabetes should change. Nope, and is only one couter example > nail in the iron causes all disease because people eat meat idea. While > many are available only one is required to toss it. COMMENT:
Diabetes II increases with obesity and obesity increases with age. However, whether iron is involved or not, obesity and age are bigger factors (age 65-75 has the most diabetes in every group).
If you want to look at iron, you have to look at DM at comparable ages, and do it before menopause. Alas, you won't find any indication there that iron is important. There is more diabetes type II in African-American women than African-American men in EVERY age group, not just those over 50. It's also true from 20 to 50. If iron were involved to some great degree, that certainly would not be the case.
http://www.ndep.nih.gov/diabetes/pubs/FS_AfricanAm.pdf
Now, it's true that iron overload hurts iron sensitity directly, and this is a big factor in iron-overload diabetes. It's not just pancreas burning out, as used to be thought.
It's also true that iron deficient animals have high glucose sensitivity-- something that makes sense because they're burning glucose like crazy to make lactate, since they can't oxidize further without iron-containing enyzmes in mitochondria. But that seems like a bad way to treat diabetes, turning yourself into a veal calf with white and weak muscles.
You might think that this increased glucose sensitivity would give iron deficient animals, decreased fasting blood glucoses. Well, you'd be wrong. It doesn't. So that's disappointing, and since diabetes is diagnosed by fasting blood glucose levels, it seems unlikely that iron status makes much difference there, unless (again) there's iron overload with tranfusions or hemochromatosis and its way over normal.
As for the paper that iron-doofus likes to quote where 6 meat eaters humans were bleed and got lower blood glucoses, it's a study of only 6 people. You don't base ideas on a unreplicated reports of what happened to 6 people, particularly when it's not supported by animal data (which it isn't-- blood glucose does NOT go down in iron deficiency animals) and by epidemiology (which it isn't-- pre-menopausal women have MORE diabetes than men of the same age).
SBH
Larry - 31 Oct 2005 16:24 GMT Tom: You need to be careful with "cause" and "associated". They have completely different meanings and you used both.
Larry
> If the above is a risk factor > for diabetes can you show an increased risk for diabetes for either [quoted text clipped - 26 lines] > DEAD PEOPLE WALKING > http://pages.ivillage.com/ironjustice/deadpeoplewalking
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