Hydrogen sulfide (H(2)S) is emerging as a physiological neuromodulator as well as a smooth muscle relaxant. We submit the first evidence that blood H(2)S levels are significantly lower in fasting ...blood obtained from type 2 diabetes patients compared with age-matched healthy subjects, and in streptozotocin-treated diabetic rats compared with control Sprague-Dawley rats. We further observed that supplementation with H(2)S or an endogenous precursor of H(2)S (l-cysteine) in culture medium prevents IL-8 and MCP-1 secretion in high-glucose-treated human U937 monocytes. These first observations led to the hypothesis that lower blood H(2)S levels may contribute to the vascular inflammation seen in diabetes.
Cardiomyopathy is a rare but life‐threatening condition in children. Myocarditis is the leading cause of dilated cardiomyopathy (DCM) and prognosis is generally poor without heart transplantation. We ...report a rare case of hypocalcemic DCM due to primary hypoparathyroidism in a male infant. In our patient, aggressive management of hypoparathyroidism significantly improved the manifestations of DCM. He is currently 10 years old and has no symptoms of exercise intolerance. Latest echocardiogram revealed near‐normal cardiac function. Our case emphasizes that early diagnosis of this treatable cause of cardiomyopathy prevents serious sequelae.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Hyperketonemia Increases Tumor Necrosis Factor-α Secretion in Cultured U937 Monocytes and Type 1 Diabetic Patients and Is
Apparently Mediated by Oxidative Stress and cAMP Deficiency
Sushil K. Jain ,
...Krishnaswamy Kannan ,
Gideon Lim ,
Robert McVie and
Joseph A. Bocchini, Jr.
From the Department of Pediatrics, Louisiana State University Health Sciences Center, Shreveport, Louisiana
Abstract
An elevated blood level of tumor necrosis factor (TNF)-α is a validated marker of vascular inflammation, which can result
in the development of vascular disease and atherosclerosis. This study examined the hypothesis that ketosis increases the
TNF-α secretion, both in a cell culture model using U937 monocytes and in type 1 diabetic patients in vivo. U937 cells were
cultured with ketone bodies (acetoacetate AA and β-hydroxybutyrate BHB) in the presence or absence of high levels of glucose
in medium at 37°C for 24 h. This study demonstrates the following points. First, hyperketonemic diabetic patients have significantly
higher levels of TNF-α than normoketonemic diabetic patients ( P < 0.01) and normal control subjects ( P < 0.01). There was a significant correlation ( r = 0.36, P < 0.05; n = 34) between ketosis and oxidative stress as well as between oxidative stress and TNF-α levels ( r = 0.47, P < 0.02; n = 34) in the blood of diabetic patients. Second, ketone body AA treatment increases TNF-α secretion, increases oxygen radicals
production, and lowers cAMP levels in U937 cells. However, BHB did not have any effect on TNF-α secretion or oxygen radicals
production in U937 cells. Third, exogenous addition of dibutyryl cAMP, endogenous stimulation of cAMP production by forskolin,
and antioxidant N -acetylcysteine (NAC) prevented stimulation of TNF-α secretion caused by AA alone or with high glucose. Similarly, NAC prevented
the elevation of TNF-α secretion and lowering of cAMP levels in H 2 O 2 -treated U937 cells. Fourth, the effect of AA on TNF-α secretion was inhibited by specific inhibitors of protein kinase A
(H89), p38-mitogen-activated protein kinase (SB203580), and nuclear transcription factor (NF)κB (NFκB-SN50). This study demonstrates
that hyperketonemia increases TNF-α secretion in cultured U937 monocytic cells and TNF-α levels in the blood of type 1 diabetic
patients and is apparently mediated by AA-induced cellular oxidative stress and cAMP deficiency.
Footnotes
Address correspondence and reprint requests to Dr. Sushil K. Jain, Department of Pediatrics, Louisiana State University Health
Sciences Center, 1501 Kings Highway, Shreveport, LA 71130. E-mail: sjain{at}lsuhsc.edu .
Received for publication 11 December 2001 and accepted in revised form 3 April 2002.
AKB, α-ketobutyric acid; ELISA, enzyme-linked immunosorbent assay; HG, high glucose; HKD, hyperketonemic; MAPK, mitogen-activated
protein kinase; NAC, N -acetylcysteine; NF, nuclear transcription factor; NKD, normoketonemic; PKA, protein kinase A; PKC, protein kinase C; PMA,
phorbol 12-myristate 13-acetate; ROS, reactive oxygen species; TNF, tumor necrosis factor.
DIABETES
Elevated Blood Interleukin-6 Levels in Hyperketonemic Type 1 Diabetic Patients and Secretion by Acetoacetate-Treated Cultured
U937 Monocytes
Sushil K. Jain , PHD ,
Krishnaswamy Kannan , PHD ,
Gideon ...Lim , MS ,
Janice Matthews-Greer , PHD ,
Robert McVie , MD and
Joseph A. Bocchini, Jr , MD
From the Department of Pediatrics, Louisiana State University Health Sciences Center, Shreveport, Louisiana
Address correspondence and reprint requests to Dr. Sushil K. Jain, Department of Pediatrics, LSU Health Sciences Center, 1501
Kings Highway, Shreveport, LA 71130. E-mail: sjain{at}lsuhsc.edu .
Abstract
OBJECTIVE —Diabetic patients have elevated blood levels of interleukin-6 (IL-6), which is known to increase inflammation and the development
of vascular disease and atherosclerosis. This study examined the hypothesis that ketosis increases the circulating levels
of IL-6 in type 1 diabetic patients as well as the secretion of IL-6 in vitro in a cell culture model using U937 monocytes.
RESEARCH DESIGN AND METHODS —Fasting blood was obtained from type 1 diabetic patients and healthy siblings. To examine the effect of ketosis, U937 monocytes
were cultured with ketone bodies (acetoacetate AA, β-hydroxybutyrate BHB) in the presence or absence of high glucose levels
in the medium at 37°C for 24 h. IL-6 was determined by the sandwich enzyme-linked immunosorbent assay method, and intracellular
reactive oxygen species (ROS) generation was detected using dihydroethidium dye.
RESULTS —The blood level of IL-6 was higher in hyperketonemic (HK) diabetic patients than in normoketonemic (NK) diabetic patients
( P < 0.05) and normal control subjects ( P < 0.05). There was a significant correlation between ketosis and IL-6 levels ( r = 0.36, P < 0.04, n = 34) in the blood of diabetic patients. Cell culture studies found that exogenous addition of the ketone body AA, but not
BHB, increases IL-6 secretion and ROS generation in U937 cells. N -acetylcysteine (NAC) prevented the IL-6 secretion in acetoacetate-treated U937 monocytes.
CONCLUSIONS —This study demonstrates that hyperketonemia increases IL-6 levels in the blood of type 1 diabetic patients and that NAC can
inhibit IL-6 secretion by U937 monocytic cells cultured in a ketotic medium.
AA, acetoacetate
AKB, α-ketobutyric acid
BHB, β-hydroxybutyrate
HK, hyperketonemic
IL-6, interleukin-6
NAC, N-acetylcysteine
NK, normoketonemic
PMA, phorbol 12-myristate 13-acetate
ROS, reactive oxygen species
Footnotes
A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances.
Accepted March 30, 2003.
Received July 8, 2002.
DIABETES CARE
The liver plays a major role in the formation of H2S, a novel signaling molecule. Diabetes is associated with lower blood levels of H2S. This study investigated the activities of ...cystathionine-γ-lyase (CSE, the enzyme that catalyzes H2S formation) in livers of type 1 diabetic (T1D) animals and in peripheral blood mononuclear cells (PBMC) isolated from T1D patients. T1D is associated with both hyperketonemia (acetoacetate and β-hydroxybutyrate) and hyperglycemia. This study also examined the role of hyperglycemia and hyperketonemia per se in decreased CSE activity using U937 monocytes and PBMC isolated from healthy subjects. Livers from streptozotocin-treated T1D rats demonstrated a significantly higher reactive oxygen species production, lower CSE protein expression and activity, and lower H2S formation compared with those of controls. Studies with T1D patients showed a decrease in CSE protein expression and activity in PBMC compared with those of age-matched normal subjects. Cell culture studies demonstrated that high glucose (25 mm) and/or acetoacetate (4 mm) increased reactive oxygen species, decreased CSE mRNA expression, protein expression, and enzymatic activity, and reduced H2S levels; however, β-hydroxybutyrate treatment had no effect. A similar effect, which was also observed in PBMC treated with high glucose alone or along with acetoacetate, was prevented by vitamin D supplementation. Studies with CSE siRNA provide evidence for a relationship between impaired CSE expression and reduced H2S levels. This study demonstrates for the first time that both hyperglycemia and hyperketonemia mediate a reduction in CSE expression and activity, which can contribute to the impaired H2S signaling associated with diabetes.
Mechanism of impaired H2S signaling in diabetes is not clear.
Livers from type 1 diabetic (T1D) rats and PBMC isolated from T1D patients have lower cystathionine-γ-lyase activity. High glucose and/or high ketone treatment also decreased cystathionine-γ-lyase activity in U937 monocytes and PBMC of healthy subjects.
Uncontrolled glycemia and ketosis down-regulate cystathionine-γ-lyase activity in T1D.
Impaired cystathionine-γ-lyase can dysregulate H2S signaling in diabetes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Erythrocytes of diabetic patients have abnormal membrane properties. We examined in vivo membrane lipid peroxidation in erythrocytes of diabetic subjects and its possible relationship with ...hyperglycemia. Lipid peroxidation was assessed in fresh, untreated erythrocytes by quantitating thiobarbituric acid reactivity and an adduct of phospholipids and malonyldialdehyde (MDA), an end product of lipid peroxidation, with thin-layer chromatography of lipid extract of diabetic erythrocytes. There was a significantly increased membrane lipid peroxidation in diabetic erythrocytes compared with nondiabetic erythrocytes. The degree of membrane lipid peroxidative damage in erythrocytes was significantly correlated with the level of glycosylated hemoglobin, an index of mean glucose level for the preceding 3-4 mo. This suggests that peroxidation of membrane lipids and accumulation of MDA occurs in erythrocytes of diabetic patients.
Hyperglycemic hyperosmolar syndrome (HHS) is a clinical entity not identical to diabetic ketoacidosis (DKA), and with a markedly higher mortality. Children with HHS can also present with concomitant ...DKA. Patients with HHS (with or without DKA) are profoundly dehydrated but often receive inadequate fluid resuscitation as well as intravenous insulin therapy based on traditional DKA protocols, and this can lead to devastating consequences. In this article, we briefly review HHS along with a report of an adolescent who presented with HHS and DKA and was initially managed as DKA. She went into hypotensive shock and developed severe, multiorgan failure. A thorough understanding of the pathophysiology of HHS and its differences from DKA in terms of initial management is crucial to guide management and improve outcomes. Additionally, fluid therapy in amounts concordant with the degree of dehydration remains the mainstay therapy.
The plasma levels of apoptotic DNA ladders (i.e., apoptosemia) and gamma-glutamyltranspeptidase (GGT) in diabetic outpatients and rats were investigated. Apoptotic DNA ladders were detected in plasma ...from 26.8% of type 1 (T1) and 18.5% of type 2 (T2) diabetic children 1-20 years of age, 25.7% of hospitalized children and 35.7% of adult RA outpatients, but in only 3.5% of adult pre-op patients. Plasma from 7.7% of young streptozotocin-induced diabetic but not control rats contained apoptotic DNA ladders. Apoptosemia was detected more often in male T1 (31%) and T2 (30.8%) diabetic outpatients than in female T1 (20.8%) and T2 (15.4%) diabetic outpatients. GGT in apoptosemic plasma was significantly higher than in nonapoptosemic plasma from T1 (P = 0.001) but not T2 diabetic children. The highest amounts of apoptotic DNA were detected most often in diabetic children > or =14 years of age. In vitro study results suggest that cell-free apoptotic DNA ladders appear prior to an increase in GGT activity in serum from human blood incubated at 37 degrees C. The results suggest that 24.7% of plasma samples from diabetic children contained apoptotic DNA ladders, the incidence and amounts of apoptotic DNA ladders were higher in the older diabetic children, and GGT was elevated in apoptosemic T1 diabetic children (P = 0.01). The results indicate that "silent" apoptosemia occurs in T1 and T2 diabetic children and suggest elevated GGT in diabetic children could be due to release from apoptotic cells.
Aims/hypothesis
We had previously reported that stromal cell-derived factor 1 (SDF-1) mediates chemorepulsion of diabetogenic T cell adhesion to islet microvascular endothelium through unknown ...mechanisms in NOD mice. Here we report that SDF-1-mediated chemorepulsion occurs through slit homologue (SLIT)2-roundabout, axon guidance receptor, homologue 1 (
Drosophila
) (ROBO1) interactions.
Methods
C-X-C receptor (CXCR)4 and ROBO1 protein expression was measured in mouse and human T cells. Parallel plate flow chamber adhesion and detachment studies were performed to examine the molecular importance of ROBO1 and SLIT2 for SDF-1-mediated T cell chemorepulsion. Diabetogenic splenocyte transfer was performed in NOD/LtSz
Rag1
−/−
mice to examine the effect of the SDF-1 mimetic CTCE-0214 on adoptive transfer of diabetes.
Results
CXCR4 and ROBO1 protein expression was elevated in diabetic NOD/ShiLtJ T cells over time and coincided with the onset of hyperglycaemia. CXCR4 and ROBO1 expression was also increased in human type 1 diabetic T cells, with ROBO1 expression maximal at less than 1 year post diagnosis. Cell detachment studies revealed that immunoneutralisation of ROBO1 prevented SDF-1-mediated chemorepulsion of NOD T cell firm adhesion to TNFα-stimulated islet endothelial cells. SDF-1 increased NOD T cell adhesion to recombinant adhesion molecules, a phenomenon that was reversed by recombinant SLIT2. Finally, we found that an SDF-1 peptide mimetic prevented NOD T cell adhesion in vitro and significantly delayed adoptive transfer of autoimmune diabetes in vivo.
Conclusions/interpretation
These data reveal a novel molecular pathway, which regulates diabetogenic T cell recruitment and may be useful in modulating autoimmune diabetes.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Vitamin E supplementation restores glutathione and malondialdehyde to normal concentrations in erythrocytes of type 1 diabetic
children.
S K Jain ,
R McVie and
T Smith
Department of Pediatrics, ...Louisiana State University Health Sciences Center, Shreveport 71130, USA. sjain@lsum.edu
Abstract
OBJECTIVE: This study examined the relationship between cellular glutathione and vitamin E concentrations and the effect of
vitamin E (alpha-tocopherol) supplementation on glutathione and lipid peroxidation product concentrations in the erythrocytes
of type 1 diabetic patients. RESEARCH DESIGN AND METHODS: We obtained written informed consent to participate in this study
from diabetic patients (n = 29) and their age-matched nondiabetic siblings (n = 21) according to the guidelines of the Institutional
Review Board on Human Experimentation. Diabetic patients were supplemented with a DL-alpha-tocopherol (vitamin E) capsule
(100 IU/orally) or placebo for 3 months in a double-blind clinical trial. Fasting blood samples were collected from each diabetic
patient before the start of and after the 3 months of vitamin E or placebo supplementation. Glutathione, malondialdehyde (which
is a product of lipid peroxidation), and alpha-tocopherol were determined using high-performance liquid chromatography A total
of 5 diabetic patients were excluded after randomization from the data analyses. Data were analyzed statistically using a
paired Students t test to compare 12 diabetic patients taking vitamin E with 12 diabetic patients receiving placebo supplementation
and to compare diabetic patients with healthy nondiabetic subjects. RESULTS: Erythrocytes of diabetic patients had 21% higher
(P<0.001) malondialdehyde and 15% lower (P<0.05) glutathione concentrations than healthy subjects. Vitamin E in erythrocytes
had a significant correlation with the glutathione concentrations in the erythrocytes (r = 0.46, P<0.02). Vitamin E supplementation
increased glutathione concentrations by 9% (P<0.01) and lowered concentrations of malondialdehyde by 23% (P<0.001) and of
HbA1c by 16% (P<0.02) in erythrocytes of diabetic patients. No differences were evident in these parameters before versus
after placebo supplementation. CONCLUSIONS: Glutathione level is significantly related to vitamin E level, and supplementation
with vitamin E (100 IU/day) significantly increases glutathione and lowers lipid peroxidation and HbA1c concentrations in
the erythrocytes of type 1 diabetic patients.
PDF
