Co-associations between insulin sensitivity and measures of liver function, subclinical inflammation, and hematology

Associations Between GGT/ALT Ratio and Carotid Plaque in Inpatients With Coronary Artery Disease: A RCSCD-TCM Study

This study investigated the relationship between gamma-glutamyltransferase/alanine aminotransferase (GGT/ALT) ratio and carotid plaques in patients with coronary artery disease (CAD). This multicenter retrospective study included 8,255 patients with CAD who were divided according to GGT/ALT quartiles: Q1 (GGT/ALT ≤ 1.00), Q2 (1.00 < GGT/ALT ≤ 1.41), Q3 (1.41 < GGT/ALT ≤ 2.05), and Q4 (GGT/ALT > 2.05). Logistic regression was used to analyze the relationship between GGT/ALT, carotid plaques, and carotid plaque echogenicity. GGT/ALT ratio (odds ratio [OR]: 1.16; 95% confidence interval [CI]: 1.11-1.21; P < .001) was significantly associated with carotid plaque risk. The degree of relevance was higher in men (OR: 1.71; 95% CI: 1.35-2.15; P < .001) than in women (OR: 1.56; 95% CI: 1.28-1.91; P < .001). The ORs value of carotid plaque risk was higher in middle-aged patients (OR: 2.23; 95% CI: 1.78-2.80; P < .001) than in older patients (OR: 1.77; 95% CI: 1.44-2.18; P < .001). The GGT/ALT ratio was significantly associated with different carotid plaque echogenicity, and the highest OR values were for isoechoic plaques (OR: 1.18; 95% CI: 1.12-1.24; P < .001). These findings suggest that the GGT/ALT ratio might be associated with a high risk of developing carotid plaques and different types of plaque echoes and was more significantly associated with isoechoic plaques.

A history of previous gestational diabetes mellitus is associated with adverse changes in insulin secretion and VLDL metabolism independently of increased intrahepatocellular lipid

AIMS/HYPOTHESIS

We have previously reported a high prevalence of non-alcoholic fatty liver disease (NAFLD) among women with previous gestational diabetes mellitus (pGDM). We wanted to confirm that intrahepatocellular lipid (IHCL) is associated with pGDM independently of adiposity and determine: (1) if VLDL metabolism is dysregulated; and (2) the extent to which NAFLD and IHCL account for the dysmetabolic phenotype in pGDM.

METHODS

We analysed data from a cohort of 234 women (114 with pGDM) and identified effects of pGDM on lipid and glucoregulation that were independent of ultrasound-diagnosed NAFLD. We then measured IHCL by MR spectroscopy in a representative subgroup (n = 36) and conducted detailed metabolic studies (IVGTT, VLDL apolipoprotein B [apoB] kinetics and palmitate turnover) and measurement of regional body fat by MRI to demonstrate effects of IHCL that were independent of a history of pGDM.

RESULTS

pGDM was associated with increased IHCL (p = 0.04) after adjustment for adiposity. Independently of IHCL, pGDM was associated with a lower IVGTT disposition index (p = 0.02) and acute insulin response to glucose (pGDM+/NAFLD-, 50% lower; pGDM+/NAFLD+, 36% lower; effect of pGDM, p = 0.03), increased VLDL apoB pool size (pGDM+/NAFLD-, 3.1-fold higher; pGDM+/NAFLD+, 1.2-fold higher; effect of pGDM, p = 0.02) and, at borderline significance (p = 0.05), increased rate of VLDL apoB synthesis.

CONCLUSIONS/INTERPRETATION

pGDM is associated with increased IHCL independently of adiposity. The increased liver fat contributes to the phenotype, but pGDM status is independently associated with diminished insulin secretion and (shown for the first time) augmented VLDL metabolism. IHCL with pGDM may compound a dysmetabolic phenotype.

Uric acid lowering to prevent kidney function loss in diabetes: the preventing early renal function loss (PERL) allopurinol study

Diabetic kidney disease causes significant morbidity and mortality among people with type 1 diabetes (T1D). Intensive glucose and blood pressure control have thus far failed to adequately curb this problem and therefore a major need for novel treatment approaches exists. Multiple observations link serum uric acid levels to kidney disease development and progression in diabetes and strongly argue that uric acid lowering should be tested as one such novel intervention. A pilot of such a trial, using allopurinol, is currently being conducted by the Preventing Early Renal Function Loss (PERL) Consortium. Although the PERL trial targets T1D individuals at highest risk of kidney function decline, the use of allopurinol as a renoprotective agent may also be relevant to a larger segment of the population with diabetes. As allopurinol is inexpensive and safe, it could be cost-effective even for relatively low-risk patients, pending the completion of appropriate trials at earlier stages.

Elevated serum uric acid levels are associated with non-alcoholic fatty liver disease independently of metabolic syndrome features in the United States: Liver ultrasound data from the National Health and Nutrition Examination Survey

OBJECTIVE

Experimental and observational studies suggest a role for uric acid in non-alcoholic fatty liver disease (NAFLD). We examined the association between serum uric acid levels and NAFLD in a large population-based study from the United States.

MATERIALS/METHODS

A cross-sectional analysis of 10,732 nondiabetic adults who participated in the National Health and Nutrition Examination Survey 1988-1994. Sex specific uric acid quartiles were defined: ≤5.2, 5.3-6.0, 6.1-6.9, and >6.9mg/dL for men and ≤3.7, 3.8-4.5, 4.6-5.3, and >5.3mg/dL for women. NAFLD presence and severity were defined by ultrasonographic detection of steatosis in the absence of other liver diseases. We modeled the probability that more severe NAFLD would be associated with the highest quartiles of uric acid.

RESULTS

Compared to the 1st quartile, the odds ratio for NAFLD was 1.79 (95% C.I. 1.49-2.15, p<0.001) and 3.14 (95% C.I. 2.63-3.75, p<0.001) for the 3rd and 4th quartiles, respectively. After adjusting for demographics, hypertension, waist circumference, triglycerides, high-density lipoprotein-cholesterol, homeostasis model assessment-estimated insulin resistance, estimated glomerular filtration rate, and aspartate aminotransferase, uric acid (4th quartile) was significantly associated with NAFLD (odds ratio 1.43; 95% C.I. 1.16-1.76, p<0.001). Positive parameter estimates suggest increasing uric acid is associated with greater severity of NAFLD.

CONCLUSIONS

Elevated uric acid level is independently associated with ultrasound-diagnosed NAFLD in a nationally representative sample of United States nondiabetic adults. Increasing uric acid is associated with increasing severity of NAFLD on ultrasonography. These findings warrant further studies on the role of uric acid in NAFLD.

Chromium dinicocysteinate supplementation can lower blood glucose, CRP, MCP-1, ICAM-1, creatinine, apparently mediated by elevated blood vitamin C and adiponectin and inhibition of NFkappaB, Akt, and Glut-2 in livers of zucker diabetic fatty rats

Chromium and cysteine supplementation can improve glucose metabolism in animal studies. This study examined the hypothesis that a cysteinate complex of chromium is significantly beneficial than either of them in lowering blood glucose and vascular inflammation markers in Zucker diabetic fatty (ZDF) rats. Starting at the age of 6 wk, ZDF rats were supplemented orally (daily gavages for 8 more weeks) with saline-placebo (D) or chromium (400 microg Cr/Kg body weight) as chromium dinicocysteinate (CDNC), chromium dinicotinate (CDN) or chromium picolinate (CP) or equimolar L-cysteine (LC, img/Kg body weight), and fed Purina 5008 diet for 8 wk. ZDF rats of 6 wk age before any supplementations and onset of diabetes were considered as baseline. D rats showed elevated levels of fasting blood glucose, HbA(1), CRP, MCP-1, ICAM-1 and oxidative stress (lipid peroxidation) and lower adiponectin and vitamin C, when compared with baseline rats. In comparison to D group, CDNC group had significantly lower blood glucose, HbA(1), CRP, MCP-1, ICAM-1 and lipid peroxidation and increased vitamin C and adiponectin levels. CDN, CP or LC showed significantly less or no effect on these biomarkers. Only CDNC lowered blood creatinine levels in comparison to D. While CDN and CP had no effect, activation of NFkappaB, Akt and glucose transporter-2 levels were decreased, insulin receptor substrate 1 (IRS-1) activation increased in livers of CDNC-rats. CDNC effect on glycemia, NFkappaB, Akt and IRS-1 in liver was significantly greater compared with LC. Blood chromium levels did not differ between Cr-groups. Exogenous vitamin C supplementation significantly inhibited MCP-1 secretion in U937 monocytes cultured in high-glucose-medium. CDNC is a potent hypoglycemic compound with anti-inflammatory activity apparently mediated by elevated blood vitamin C and adiponectin and inhibition of NFkappaB, Akt, and Glut-2 and increased IRS-1 activation in livers of type 2 diabetic rats.

Insulin resistance-related biomarker clustering and subclinical inflammation as predictors of cancer mortality during 21.5 years of follow-up

OBJECTIVES

Risk of cancer is increased in conditions associated with insulin resistance, but this could be secondary to subclinical inflammation. We evaluated whether insulinemia, indices of insulin resistance or a validated insulin resistance-related biomarker cluster, could predict cancer mortality independently of subclinical inflammation.

METHODS

Fasting insulin and glucose concentrations and insulin-related metabolic variables were recorded in 1,016 white males, of whom 718 also had an oral glucose tolerance test (OGTT). Baseline measurements included the following: fasting insulin and the derived insulin resistance index, HOMA-IR; OGTT insulin and the derived insulin resistance index, Matsuda-IS; the factor score for a validated insulin resistance-related biomarker cluster; white blood cell count; erythrocyte sedimentation rate; and serum albumin and globulin concentrations.

RESULTS

There were 105 deaths from cancer during the 21.5-year mean follow-up. Insulin concentrations and insulin resistance were not predictive. Insulin resistance-related biomarker clustering predicted cancer mortality (hazard ratio 1.65, 95% CI 1.26-2.17, p < 0.001). Subclinical inflammation markers were also predictive, but the insulin resistance-related biomarker cluster predicted cancer mortality independently of these and was particularly associated with death from colorectal cancer.

CONCLUSIONS

Despite insulin concentrations or derived indices of insulin resistance failing to predict cancer mortality, insulin resistance-related biomarker clustering was highly predictive and predicted independently of simple measures of subclinical inflammation.

Inflammation, aging, and cancer: tumoricidal versus tumorigenesis of immunity: a common denominator mapping chronic diseases

Acute inflammation is a highly regulated defense mechanism of immune system possessing two well-balanced and biologically opposing arms termed apoptosis ('Yin') and wound healing ('Yang') processes. Unresolved or chronic inflammation (oxidative stress) is perhaps the loss of balance between 'Yin' and 'Yang' that would induce co-expression of exaggerated or 'mismatched' apoptotic and wound healing factors in the microenvironment of tissues ('immune meltdown'). Unresolved inflammation could initiate the genesis of many age-associated chronic illnesses such as autoimmune and neurodegenerative diseases or tumors/cancers. In this perspective 'birds' eye' view of major interrelated co-morbidity risk factors that participate in biological shifts of growth-arresting ('tumoricidal') or growth-promoting ('tumorigenic') properties of immune cells and the genesis of chronic inflammatory diseases and cancer will be discussed. Persistent inflammation is perhaps a common denominator in the genesis of nearly all age-associated health problems or cancer. Future challenging opportunities for diagnosis, prevention, and/or therapy of chronic illnesses will require an integrated understanding and identification of developmental phases of inflammation-induced immune dysfunction and age-associated hormonal and physiological readjustments of organ systems. Designing suitable cohort studies to establish the oxido-redox status of adults may prove to be an effective strategy in assessing individual's health toward developing personal medicine for healthy aging.

L-cysteine supplementation lowers blood glucose, glycated hemoglobin, CRP, MCP-1, and oxidative stress and inhibits NF-kappaB activation in the livers of Zucker diabetic rats

This study examined the hypothesis that l-cysteine supplementation can lower insulin resistance, glycemia, oxidative stress, and markers of vascular inflammation in type 2 diabetes using Zucker diabetic fatty (ZDF) rats as a model. Starting at the age of 6 weeks, ZDF rats were supplemented orally (daily gavage, 8 weeks) with saline placebo (D) or l-cysteine (LC; 1 mg/kg bw) and fed a high-calorie diet. Six-week-old rats without any supplementation were considered baseline (BL) rats. D rats showed elevated fasting blood glucose, glycated Hb, CRP, and MCP-1 compared with BL rats in which there was no onset of diabetes. LC supplementation significantly lowered blood levels of glucose (18%, p= 0.05), glycated Hb (8%, p= 0.02), CRP (23%, p= 0.02), MCP-1 (32%, p= 0.01), and insulin resistance (25%) compared with levels seen in saline-supplemented D rats. There was a decrease in plasma protein oxidation levels (p< 0.01); however, GSH levels were similar in LC and D groups. Although LC did not change blood hematocrit or levels of transaminases, it did lower alkaline phosphatase (29%, p= 0.01) levels in comparison to D. Western blotting analyses of liver showed increased activation of NF-kappaB and Akt (50% pNF-kappaB and 20% pAkt) in D compared with BL rats. LC supplementation inhibited these effects (17% pAkt, 18% pNF-kappaB). This is the first report showing that l-cysteine supplementation can lower glycemia and markers of vascular inflammation in diabetes apparently by preventing NF-kappaB activation in a diabetic animal model.