Recurrent high-dose intravenous methylprednisolone succinate pulse therapy-induced hepatopathy in a patient with multiple sclerosis.

OBJECTIVE: We describe recurrent and reversible hepatopathy in a girl with multiple sclerosis (MS) after glucocorticoid pulse therapy, to point out the possibility that glucocorticoid may harm the liver. CLINICAL PRESENTATION AND INTERVENTION: An 11-year-old girl with MS, who was treated with high-dose methylprednisolone succinate pulse therapy, developed elevation of liver enzymes. The episodes of hepatopathy occurred 1-5 weeks after the therapy and disappeared within several weeks. The examination for antinuclear antibody and viruses which can cause hepatitis produced negative results. CONCLUSION: The present case emphasizes the possible effects of high-dose glucocorticoids in the induction of liver enzymes and the importance of follow-up liver tests after pulse therapy.

Biological roles of anti-GM1 antibodies in patients with Guillain-Barré syndrome for nerve growth factor signaling.

To reveal the biological and pathological roles of anti-GM1 antibody in Guillain-Barré syndrome (GBS), we examined its effects on nerve growth factor (NGF) induced TrkA autophosphorylation (NGF-TrkA signaling) in PC12 cells, a sympathetic nerve cell line. The NGF-TrkA signaling is enhanced by exogenous GM1 ganglioside and this phenomenon is regarded as one of the functional aspects of GM1. The IgGs purified from patients' sera inhibited the NGF-TrkA signaling in GM1 pre-incubated PC12 cells. The degrees of inhibition by IgGs from patients paralleled their immunological reactivity to GM1. In addition, the IgGs also inhibited the neurite outgrowth of NGF-treated PC12 cells. Immunoglobulins in the rabbit sera, which were immunized by GM1, also caused a similar suppressive phenomenon. These results suggested that the anti-GM1 antibody could play roles in pathophysiology in anti-GM1 antibody positive GBS through interfering with the neurotrophic action of NGF and GM1 mediated signal modulation including NGF-TrkA signaling. It is suggested that the modulation of GM1 function is one important action of antibodies and could be one of the important mechanisms in GBS.

In vivo activation of the constitutive androstane receptor beta (CARbeta) by treatment with dehydroepiandrosterone (DHEA) or DHEA sulfate (DHEA-S).

We investigated whether dehydroepiandrosterone (DHEA) or DHEA-sulfate (S) affected the activities of nuclear receptors, with special reference to constitutive androstane receptor beta (CARbeta). Administration of DHEA or DHEA-S enhanced the DNA binding of hepatic nuclear extracts to responsive elements for the retinoic acid receptor, the retinoic acid receptor beta 2 and the peroxisome proliferator activated receptor. The bound complexes were shown to be the CARbeta-RXR heterodimer by antibody-supershift assays. The expression of a target gene of CARbeta, Cyp2b10, was increased in liver by DHEA or DHEA-S treatment, suggesting that DHEA or DHEA-S actually activated CARbeta in vivo. It was suggested that the metabolic conversion of DHEA, DHEA-S to CARbeta ligands could occur in vivo and the metabolites could regulate the expression of CARbeta target gene expression. Our results provide new insights into the in vivo relationship between DHEA/DHEA-S and CARbeta activation.

Possible de novo CTG repeat expansion in the DMPK gene of a patient with cardiomyopathy.

CTG triplet repeats of "normal" length in the myotonic dystrophy protein kinase (DMPK) gene have been previously believed to be stable and new pathological expansion was not believed to occur. Here we report possible de novo CTG repeat expansion in the DMPK gene in a patient with cardiomyopathy, who was not diagnosed as having myotonic dystrophy type 1 (DM1) by conventional genetic tests.

Adrenal androgen dehydroepiandrosterone sulfate inhibits vascular remodeling following arterial injury.

Recent epidemiologic studies have suggested that serum dehydroepiandrosterone sulfate (DHEAS) levels have a significant inverse correlation with the incidence of cardiovascular diseases. However, direct evidence for the association with DHEAS and vascular disorders has not yet been explored. DHEAS significantly reduced neointima formation 28 days after surgery without altering other serum metabolite levels in a rabbit carotid balloon injury model. Immunohistochemical analyses revealed the reduction of proliferating cell nuclear antigen (PCNA) index and increase of TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) index, expressing differentiated vascular smooth muscle cell (VSMC) markers in the media 7 days after surgery. In vitro, DHEAS exhibited inhibitory effects on VSMC proliferation and migration activities, inducing G1 cell cycle arrest with upregulation of one of the cyclin dependent kinase (CDK) inhibitors p16(INK4a) and apoptosis with activating peroxisome proliferator-activated receptor (PPAR)-alpha in VSMCs. DHEAS inhibits vascular remodeling reducing neointima formation after vascular injury via its effects on VSMC phenotypic modulation, functions and apoptosis upregulating p16(INK4a)/activating PPARalpha. DHEAS may play a pathophysiological role for vascular remodeling in cardiovascular disease.

Serum concentrations of granulocyte colony-stimulating factor (G-CSF) in antithyroid drug-induced agranulocytosis.

Granulocyte colony-stimulating factor (G-CSF) levels in serum were determined by a highly-sensitive chemiluminescent enzyme immunoassay (limit of detection, 0.5 pg/ml) in 54 patients with Graves' disease including 6 patients complicated with methimazole-induced agranulocytosis. Serum G-CSF levels in patients with Graves' disease were not different from normal subjects and did not correlate with serum FT4 level or circulating neutrophil counts. Before the onset of agranulocytosis, there was no difference in serum G-CSF level between the patients complicated with agranulocytosis and the uncomplicated patients. When circulating neutrophil counts decreased to less than 0.5 x 10(9)/L, serum G-CSF level elevated with the mean of 106.8 +/- 82.2 (SD) pg/ml, but the level did not correlate with the duration of agranulocytosis. Interestingly, maximum serum G-CSF level during the treatment with recombinant human G-CSF (100 microg/day) was related to bone marrow finding at the onset of agranulocytosis and correlated with the duration of agranulocytosis (r = 0.824, p < 0.05). In conclusion, measuring serum G-CSF levels with a highly-sensitive chemiluminescent enzyme immunoassay revealed that 1) thyrotoxicosis does not affect serum G-CSF level, 2) serum G-CSF level during antithyroid drug treatment does not play an important role in development of agranulocytosis, 3) the maximum serum G-CSF level in the course of agranulocytosis is related to the responsiveness of bone marrow to G-CSF and the recovery time from agranulocytosis.