Differential regulation of 11beta-hydroxysteroid dehydrogenase-1 by dexamethasone in glucocorticoid-sensitive and -resistant childhood lymphoblastic leukemia

Glucocorticoid therapy forms a crucial first-line treatment for childhood acute lymphoblastic leukemia (ALL). However, glucocorticoid resistance is a therapeutic problem with an unclear molecular mechanism. 11beta-Hydroxysteroid dehydrogenase-1 (11beta-HSD1) is expressed in glucocorticoid target tissue, where it regenerates active glucocorticoids from inert 11keto-glucocorticoids, amplifying intracellular glucocorticoid levels. Here, we show 11beta-HSD1 expression in leukemic cells from ALL patients (n=14). 11beta-HSD1 was differentially regulated by glucocorticoids between glucocorticoid-sensitive and -resistant ALL cells. Dexamethasone increased 11beta-HSD1 mRNA levels in glucocorticoid-sensitive ALL cells, but decreased levels in the resistant group. Our data suggest that differential induction of 11beta-HSD1 contributes to the glucocorticoid sensitivity in leukemia.

Cytochrome P450 oxidoreductase deficiency with Antley-Bixler syndrome: steroidogenic capacities

For patients with cytochrome P450 oxidoreductase deficiency (PORD), steroid replacement is recommended at times of stress. However, it is unknown how hormones respond to actual physical stress in these patients. We report a female infant with PORD accompanied by the Antley-Bixler syndrome phenotype. Her urinary steroid profile revealed defective CYP17A1 and CYP21A2 activities, and an adrenocorticotropin (ACTH) stimulation test showed potential adrenal insufficiency. Hormonal responses to actual physical stress were as follows: Vigorous crying during blood sampling rarely affected the serum cortisol level. Acute viral gastroenteritis led to marked increases in blood ACTH and 17alpha-hydroxyprogesterone levels in proportion to the severity of the illness. The serum cortisol level also responded to this stress, but the response might have been blunted. Regarding peri-operative steroid replacement, intravenous hydrocortisone administration even at a dose of 6 mg/kg, which is lower than that recommended for congenital adrenal hyperplasia in Japan, proved to be excessive.

Glucocorticoid regulation of the promoter of 11beta-hydroxysteroid dehydrogenase type 1 is indirect and requires CCAAT/enhancer-binding protein-beta

11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts inert 11keto-glucocorticoids to active 11beta-hydroxy forms, thereby amplifying intracellular glucocorticoid action. Up-regulation of 11beta-HSD1 in adipose tissue and liver is of pathogenic importance in metabolic syndrome. However, the mechanisms controlling 11beta-HSD1 transcription are poorly understood. Glucocorticoids themselves potently increase 11beta-HSD1 expression in many cells, providing a potential feed-forward system to pathology. We have investigated the molecular mechanisms by which glucocorticoids regulate transcription of 11beta-HSD1, exploiting an A549 cell model system in which endogenous 11beta-HSD1 is expressed and is induced by dexamethasone. We show that glucocorticoid induction of 11beta-HSD1 is indirect and requires new protein synthesis. A glucocorticoid-responsive region maps to between -196 and -88 with respect to the transcription start site. This region contains two binding sites for CCAAT/enhancer-binding protein (C/EBP) that together are essential for the glucocorticoid response and that bind predominantly C/EBPbeta, with C/EBPdelta present in a minority of the complexes. Both C/EBPbeta and C/EBPdelta are rapidly induced by glucocorticoids in A549 cells, but small interfering RNA-mediated knockdown shows that only C/EBPbeta reduction attenuates the glucocorticoid induction of 11beta-HSD1. Chromatin immunoprecipitation studies demonstrated increased binding of C/EBPbeta to the 11beta-HSD1 promoter in A549 cells after glucocorticoid treatment. A similar mechanism may apply in adipose tissue in vivo where increased C/EBPbeta mRNA levels after glucocorticoid treatment were associated with increased 11beta-HSD1 expression. C/EBPbeta is a key mediator of metabolic and inflammatory signaling. Positive regulation of 11beta-HSD1 by C/EBPbeta may link amplification of glucocorticoid action with metabolic and inflammatory pathways and may represent an endogenous innate host-defense mechanism.

A case of congenital chloride diarrhea: information obtained through long-term follow-up with reduced electrolyte substitution

Congenital chloride diarrhea (CCD) is an inherited disorder of intestinal electrolyte transport that results in a large wastage of electrolytes and water. The patient, who is now 24 years old, was diagnosed at the age of 16 months with CCD based on hypochloremic alkalosis, hyponatremia, and hypokalemia with increased plasma renin and aldosterone levels, and high fecal Cl(-). Serum Na(+) and plasma aldosterone levels were normalized by replacement therapy with NaCl [8 mmol/(kg day)] and KCl [3 mmol/(kg day)]. On follow-up, watery diarrhea persisted, and she was frequently noted to have hypokalemia despite normal serum Na(+) and Cl(-) and plasma aldosterone levels with only reduced dosages of KCl [1-1.5 mmol/(kg day)] substitution due to only sporadic ambulatory care and unsatisfactory compliance with medication, and a normal diet. However, she had acceptable growth, normal renal function, and had an uneventful pregnancy and delivery of a healthy child. In adolescence and adulthood, hypokalemia may be the main problem requiring treatment, and substitution therapy with adequate doses of KCl alone may be sufficient, although a combination of NaCl and KCl is generally recommended even after childhood.

Ultrasound-guided versus landmark-guided femoral vein access in pediatric cardiac catheterization

BACKGROUND

This study aimed to evaluate whether an ultrasound-guided technique can improve upon a landmark-guided technique in achieving femoral vein access in pediatric cardiac catheterization.

METHODS

This study examined 87 consecutive subjects with a median age of 2 years (range, 1 month to 19 years) who had congenital or other heart disease. Femoral vein puncture was attempted using either an ultrasound-guided technique (US group, n = 43) or a landmark-guided technique (LM group, n = 44). The patients were assigned alternately to either an ultrasound- or landmark-guided group. Overall success and traumatic complication rates were compared between the two groups, as well as the influence of patient size and age.

RESULTS

The overall rate of success in achieving femoral vein access did not differ between the two groups. Among the successful cases in the two groups, there were no significant differences in patient size or age. Inadvertent femoral artery puncture occurred with 3 (7%) of 43 patients in the US group and with 14 (31.8%) of 44 patients in the LM group, for a significantly higher complication rate in the LM group (p < 0.01).

CONCLUSIONS

Ultrasound-guided access to the femoral vein minimizes the complication of inadvertent arterial puncture as compared with the landmark-guided approach.

[Genetic regulation of the biosynthesis of steroid hormones]

Steroid hormones play the critical roles in human. Glucocorticoid is indispensable for the life. Mineralocorticoid regulates the balance of electrolytes. Androgen and estrogen are necessary for sexual development. In the biosynthesis of steroid hormone, many cytochrome P450 enzymes and hydroxysteroid dehydrogenases work. P450 enzymes catalyze the hydroxylation and cleavage of the steroid substrate. They function as monooxygenases utilizing NADPH as the electron donor for the reduction of molecular oxygen. The hydroxysteroid dehydrogenases belong to the short-chain alcoholdehydrogenase reductase superfamily. They are involved in the reduction and oxidation of steroid hormones requiring NAD+/NADP+ as acceptors. Most genes and genetic regulation of these enzymes have been clarified. This review presents a description of the enzymes and the genes involved in the biosynthesis of active steroid hormones.

Extremely low birthweight infant with wolf-hirschhorn syndrome: a dilemma in determination of the optimal timing of delivery

Wolf-Hirschhorn syndrome (WHS) is characterized by multiple malformations as well as mental and developmental defects resulting from the absence of a distal segment of the short arm of chromosome 4. We experienced an extremely low birthweight infant with WHS. The male infant (birthweight 934 g) was born at 31 weeks’ gestation by cesarean section due to intrauterine growth restriction and presented with the typical WHS phenotype. Chromosomal analysis showed a deletion: 46,XY,del(4)(p15.3 p16). Although the patient’s respiratory distress syndrome resolved favourably and his subsequent condition was also stable, he had unusually severe retinopathy of prematurity and periventricular leukomalacia. We suppose that these severe complications were associated with not only prematurity but also with latent structural fragility due to WHS. Herein, we discuss the prenatal detection of WHS and the optimal timing of delivery.

Metabolic syndrome in youths

The metabolic syndrome (MetS), characterized by a clustering of cardiovascular disease and type 2 diabetes (T2DM) risk factors, has become prevalent in children and adolescents in recent years. However, the reported prevalence data on the MetS in youths has varied markedly, in large part, because of the disagreement among the variously proposed definitions of the MetS. Obesity is defined by using body mass index, waist circumference, or percent overweight, pointing to the need for standardized use of anthropometric variables to define obesity with a well-defined reference year for each ethnic population. In addition, slightly different cutoff values are used for triglycerides, high-density lipoprotein cholesterol, blood pressure, and fasting plasma glucose. Therefore, International Diabetes Federation recently proposed unified, easy-to-use criteria for diagnosing the MetS in youths. To provide insight into the mechanisms underlying the MetS in youths, the degree of insulin sensitivity/resistance and its correlation with the serum lipid and blood pressure levels have been evaluated. In addition, the serum levels of adipocytokines, such as adiponectin, leptin, tumor necrosis factor-alpha, resistin, interleukin-6, plasminogen activator inhibitor-1, and their correlation with childhood obesity have been extensively investigated. Recommendations for future research include exploring ways to assess visceral adiposity, to identify better biochemical markers for prediction of T2DM and disease progression, and to effectively intervene to prevent the MetS in youths.

Severe, widespread vasculopathy in late-onset group B streptococcal meningitis

Although improvements in antimicrobial therapy during the last few decades have decreased mortality in childhood bacterial meningitis, some patients are left with neurologic sequelae. Cerebrovascular complications are often associated with unfavorable clinical outcome of the disease. We report a 36-day-old infant with severe, widespread cerebrovascular complications due to group B streptococcal meningitis. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) contributed to a non-invasive demonstration of meningeal inflammatory changes and vascular lesions with the meningitis in this patient.

Diabetic pregnancy in rats leads to impaired glucose metabolism in offspring involving tissue-specific dysregulation of 11beta-hydroxysteroid dehydrogenase type 1 expression

Population-based studies have shown that the offspring of diabetic mothers have an increased risk of developing obesity, insulin resistance, type 2 diabetes and hypertension in later life. To investigate mechanism for the high incidence of metabolic diseases in the offspring of diabetic mothers, we focused on the tissue-specific glucocorticoid regulation by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) and studied offspring born to streptozotocin-induced diabetic rats. The body weights of newborn rats from diabetic mothers were heavier than those from control mothers. Offspring born to diabetic mothers demonstrated insulin resistance and mild glucose intolerance after glucose loading at 10 weeks and showed significantly increased 11beta-HSD1 mRNA and enzyme activity in adipose tissue at 12 weeks of age without obvious obesity. Hepatic 11beta-HSD1 mRNA was also elevated. We propose that the 11beta-HSD1 in adipose tissue and liver may play a key role in the development of metabolic syndrome in the offspring of diabetic mothers. Tissue-specific glucocorticoid dysregulation provides a candidate mechanism for the high incidence of metabolic diseases in the offspring of diabetic mothers. Therefore early analyses before apparent obesity are needed to elucidate the molecular mechanisms that may be programmed during the fetal period.

Pilot study of ifosfamide/carboplatin/etoposide (ICE) for peripheral blood stem cell mobilization in patients with high-risk or relapsed medulloblastoma

OBJECTIVES

The purpose of this study is to evaluate the stem cell mobilization capacity, anti-tumor effect, and feasibility of ifosfamide/carboplatin/etoposide (ICE) for transplant-eligible patients with medulloblastoma.

MATERIALS AND METHODS

Six patients (23 months to 18 years old) with high-risk or relapsed medulloblastoma received one cycle of ICE, which consisted of ifosfamide at 1.8 g/m(2) for 5 days, carboplatin 400 mg/m(2) for 2 days, and etoposide 100 mg/m(2) for 5 days. Stem cells were mobilized with ICE followed by granulocyte colony-stimulating factor at 10 microg kg(-1) day(-1).

RESULTS

After one cycle of ICE, the median number of harvested CD34+ cells per apheresis session was 11.85 x 10(6) cells/kg (range, 0.2 to 71.2 x 10(6) cells/kg). Two patients obtained a complete response and three patients a partial response. All patients experienced severe myelosuppression, and three infectious toxicities were observed.

CONCLUSIONS

These results suggest that ICE is optimal for mobilizing stem cells, effective for high-risk or relapsed medulloblastoma, and tolerable with limited non-hematological toxicity.

Ulinastatin Therapy in Kawasaki Disease

BACKGROUND AND OBJECTIVE

Ulinastatin therapy may be an additional therapeutic approach to Kawasaki disease (KD). This study set out to determine whether primary intravenous ulinastatin therapy has more beneficial effects than intravenous immunoglobulin (IVIG) therapy in the acute phase of KD, and whether addition of ulinastatin to IVIG might improve outcomes in KD.

METHODS

Patients were included in the study if they had a diagnosis of KD with a Harada's score that predicted coronary artery lesions. Subjects were selected to receive either primary ulinastatin therapy (30 000 U/kg/day for 3 days) or IVIG therapy (1 g/kg/dose) using sealed envelopes. Of the 27 study subjects, 18 were assigned to the ulinastatin group, and nine to the IVIG group. IVIG therapy could be added to ulinastatin therapy if patients experienced adverse effects of ulinastatin, were found to have complicated coronary artery lesions, or developed prolonged fever or elevated white blood cell counts or C-reactive protein levels.

RESULTS

More patients receiving IVIG as primary therapy had reduced fever and C-reactive protein levels than patients receiving ulinastatin as primary therapy. Five patients in the ulinastatin group (28%) improved without additional IVIG therapy. These patients had lower white blood cell counts and C-reactive protein levels on admission.

CONCLUSION

Primary ulinastatin therapy prevented coronary artery lesions in only 28% of cases of KD with a Harada's score predictive of such lesions. Primary ulinastatin therapy may not be the treatment of first choice for preventing coronary artery lesions in patients with KD.

Differential effect of DHEA on mitogen-induced proliferation of T and B lymphocytes

Dehydroepiandrosterone (DHEA) is the predominant steroid hormone secreted by adrenal gland, and it has been proposed in recent years that DHEA has significant effects on immune function. We investigated the effect of DHEA (1 x 10(-5) - 1 x 10(-8)M) on proliferation of human T cells and B cells and on immunoglobulin production, a representative function of B cells. High doses of DHEA (1 x 10(-5)) significantly inhibited proliferation of peripheral blood mononuclear cells (PBMCs) and T cells induced by T cell mitogens hemagglutinin (PHA) and concanavalin A (Con A). Proliferation of PBMCs induced by B cell mitogens pokeweed mitogen (PWM) was increased by 1 x 10(-7) - 1 x 10(-6)M DHEA. Proliferation of PBMCs and B cells induced by Staphylococcus aureus Cowan strain I (SAC) was not significantly changed at any concentrations of DHEA. However, a concentration of 1 x 10(-7)M DHEA tended to potentiate their proliferation. This study suggested that DHEA acted on T and B lymphocytes differentially in immune system.