Properties of glucocorticoid receptors in Epstein-Barr virus-transformed lymphocytes from patients with familial cortisol resistance.

In a previous report of two patients with familial glucocorticoid resistance due to reduced numbers of glucocorticoid receptors (GR), we have shown decreased numbers of GR in peripheral mononuclear cells and cultured fibroblasts but normal affinity of GR in both patients. In this study, peripheral lymphocytes from these patients, one patient's son and daughter, and normal subjects were transformed with Epstein-Barr virus. Reduced numbers and normal affinity of GR were found in the Epstein-Barr virus-transformed lymphocytes from both patients while the son and daughter had normal numbers and affinity of GR. The thermal stability of GR and thermal activation of cytosolic receptors in both patients were found to be normal. Although the percentages of nuclear bound GR were similar in both patients and normal controls, the absolute amounts of nuclear bound GR of the patients were about one-half that of normal controls. These abnormal properties of GR (reduced numbers of GR) were preserved in the transformed cells from the patients.

Glucocorticoid effects on myeloma cells in culture: correlation of growth inhibition with induction of glucocorticoid receptor messenger RNA.

Glucocorticoids are widely used for the treatment of multiple myeloma. To investigate the direct actions of glucocorticoids on myeloma cells, we have used three cell lines of human multiple myeloma, OPM-1, OPM-2, and RPMI 8226. When growth curves of these cells were examined, OPM-1 cells were resistant, while OPM-2 were sensitive to dexamethasone (DEX). In cultures of OPM-2 cells, addition of DEX led to virtual cessation of growth, with only 16% of the residual cells viable after 4 days. RPMI 8226 appeared to be slightly sensitive, showing some slowing of growth for several days in DEX, with later recovery. Viabilities of OPM-1 and RPMI 8226 cells were not affected. Secretion of immunoglobulin (Ig-lambda) was also partially suppressed, by 30% in OPM-2 and 14% in OPM-1. No significant suppression was observed in RPMI 8226. To explore the mechanism of these differential responses to the steroid, glucocorticoid receptor (GR) was examined. Binding assays showed high affinity binding sites in all three cell lines: 64 +/- 11 fmol/10(6) cells in OPM-1, 78 +/- 14 in OPM-2, and 62 +/- 16 in RPMI 8226. Nuclear transfer of GR and DNA-cellulose binding after heat activation appeared similar in all three cell lines. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of cytosol proteins labeled with [3H]dexamethasone mesylate showed a GR of Mr 95,000 in all three. When GR mRNA was studied in these cells, all of them had GR mRNA of approximately 7 kilobases, but OPM-2 and RPMI 8226 had 3 times more GR mRNA than OPM-1. OPM-2 GR mRNA was induced 2-fold by DEX treatment at 5 x 10(-9) M or greater. OPM-1 GR mRNA was much less sensitive, with no response at less than 10(-6) M DEX and only 1.5-fold induction at that concentration. These results demonstrate that some myeloma cells can be killed by a direct action of glucocorticoids. The quantity and affinity of GR in the cells were not predictive of this response. Therefore, we propose that the resistance of OPM-1 and the relative resistance of RPMI 8226 to glucocorticoid inhibition of cell growth is by post-receptor mechanisms. The high sensitivity of induction of GR mRNA in OPM-2 may correlate with glucocorticoid-evoked cell kill.

The maze-making and solving technique for coil embolization of large and giant aneurysms.

BACKGROUND AND PURPOSE: Despite major progress in treating aneurysms by coil embolization, the complete occlusion of aneurysms of >10 mm in diameter (large/giant aneurysms) remains challenging. We present a novel endovascular treatment method for large and giant cerebral aneurysms called the "maze-making and solving" technique and compare the short-term follow-up results of this technique with those of conventional coil embolization. MATERIALS AND METHODS: Eight patients (65 ± 11.5 years of age, 7 women) with large/giant unruptured nonthrombosed cerebral aneurysm (mean largest aneurysm dimension, 19 ± 4.4 mm) were treated by the maze-making and solving technique, a combination of the double-catheter technique and various assisted techniques. The coil-packing attenuation, postoperative courses, and recurrence rate of this maze group were compared with 30 previous cases (conventional group, 65.4 ± 13.0 years of age; 22 women; mean largest aneurysm dimension, 13.4 ± 3.8 mm). RESULTS: Four maze group cases were Raymond class 1; and 4 were class 2 as indicated by immediate postsurgical angiography. No perioperative deaths or major strokes occurred. Mean packing attenuation of the maze group was significantly higher than that of the conventional group (37.4 ± 5.9% versus 26.2 ± 5.6%). Follow-up angiography performed at 11.3 ± 5.4 months revealed no recurrence in the maze group compared with 39.2% in the conventional group. CONCLUSIONS: The maze-making and solving technique achieves high coil-packing attenuation for efficient embolization of large and giant cerebral aneurysms with a low risk of recurrence.

Inhibitory effect of somatomedin C/insulin-like growth factor I on adrenocorticotropin- or forskolin-induced steroidogenesis in isolated rat adrenocortical cells.

The effects of recombinant human somatomedin C/insulin-like growth factor (IGF-I) on the steroidogenic response of isolated rat adrenocortical cells to ACTH, forskolin, and (Bu)2cAMP were examined during short term incubations. The effect of IGF-I on cAMP production by cells stimulated with ACTH or forskolin was also examined. IGF-I inhibited ACTH-, forskolin-, and (Bu)2cAMP-induced corticosterone production in a concentration-dependent manner. IGF-I (30 ng/ml) also significantly inhibited ACTH-induced cAMP production. However, the peptide had no significant effect on forskolin-induced cAMP production. IGF-I suppressed ACTH-induced cAMP production both in the presence and absence of 3-isobutyl-1-methylxanthine, suggesting that IGF-I acts to inhibit the formation of cAMP rather than the stimulation of cAMP degradation. The observation that IGF-I inhibited steroidogenesis induced by (Bu)2cAMP strongly suggests that one site of inhibition is at some step(s) distal to cAMP formation. However, the inhibition of cAMP production after stimulation with ACTH also suggests a plasma membrane site of action for IGF-I in adrenocortical cells.

Quantitative comparison of aromatase induction by dexamethasone in fibroblasts from a patient with familial cortisol resistance and a patient with cortisol hyperreactive syndrome.

The ability of dexamethasone to induce aromatase activity was tested in fibroblasts from a patient with familial cortisol resistance, a patient with cortisol hyperreactive syndrome, and five normal subjects. Dexamethasone increased enzyme activity in all cases in a concentration-dependent manner (over a range of 1-1000 nmol/L). In fibroblasts from a patient with familial cortisol resistance, the response curve of dexamethasone-induced aromatase activity was shifted to the right compared to that of normal cells. However, the maximal induction of the enzyme at 1 mumol/L dexamethasone was unchanged in cortisol-resistant fibroblasts. On the other hand, in fibroblasts from the patient with the cortisol hyperreactive syndrome, the half-maximal effect of dexamethasone was similar to that in normal cells, but maximum induction of aromatase activity was 2 times greater than that in normal cells. The glucocorticoid antagonist RU 486 inhibited dexamethasone-induced aromatase activity in these patients' cells and in normal cells in a concentration-dependent manner, indicating that the altered effects of dexamethasone on aromatase induction observed in each cell type were mediated through glucocorticoid receptors.

Augmented induction by dexamethasone of metallothionein IIa messenger ribonucleic acid in fibroblasts from a patient with cortisol hyperreactive syndrome.

Northern blot analysis was used to investigate the effect of dexamethasone (Dex) or zinc on messenger RNA (mRNA) levels of metallothionein-IIa (MT-IIa) in fibroblasts from a patient with cortisol hyperreactive syndrome and from three normal subjects. Dex was seen to increase MT-IIa mRNA levels and brought them to a maximum after 12 h. Zinc also increased the levels of MT-IIa mRNA and brought them to a maximum at 8 h after the addition. Dex as well as zinc caused a dose-related increase in MT-IIa mRNA levels. Dex had a maximal inductive effect on MT-IIa at a concentration of 10(-6) mol/L and zinc at a concentration of 10(-4) mol/L. There was no significant difference in the levels of basal expression of the MT-IIa gene between the patient's and normal fibroblasts. But in three separate experiments induction of MT-IIa gene by Dex obtained for the patient's fibroblasts was almost twice as much as that for normal fibroblasts. On the other hand, there were no significant difference in induction by zinc between the patient's and normal fibroblasts. These data indicated that the patient's cells were hyperreactive to glucocorticoids as seen from the effect of Dex on the MT-IIa mRNA levels.

A patient with hypocortisolism and Cushing's syndrome-like manifestations: cortisol hyperreactive syndrome.

One patient is reported who has the manifestations of Cushing's syndrome in spite of persistent hypocortisolemia. His serum levels of cortisol and free cortisol were below normal, and 24-h urinary excretion of 17-hydroxycorticosteroids and cortisol were decreased. There was a rapid and substantial increase in serum cortisol in response to synthetic ACTH-(1-24). Plasma levels of ACTH were marginally increased by successive administration of CRH and vasopressin, which were followed by substantial increases in serum cortisol. Glucocorticoid activity of the patient's serum, as measured by a RRA was low. There were no responses of urinary 17-hydroxycorticosteroids after metyrapone treatment. These laboratory examinations ruled out any known clinical conditions resulting in hypocortisolemia. The clinical condition could also be explained by cortisol hyperreactivity of the patient's cells. In vitro hyperreactivity to glucocorticoids was demonstrated in cultured skin fibroblasts whose aromatase activity was increased 1.5- to 1.8-fold above that of normal cells, and [3H]thymidine incorporation was inhibited more effectively by the addition of cortisol or dexamethasone. The mechanism by which the patient is hyperreactive to glucocorticoids remains unexplained.

Primary cortisol resistance accompanied by a reduction in glucocorticoid receptors in two members of the same family.

This report describes studies of a man suspected of having primary cortisol resistance. This conclusion is based on his high plasma cortisol levels and high 24-h urinary 17-hydroxycorticosteroid and cortisol excretion, plus the fact that he had no manifestations of Cushing's syndrome. Among family members tested, his mother also had hypercortisolemia. Both mother and son had high levels of unbound plasma cortisol, but their plasma ACTH concentrations were within the normal range. Both were partially resistant to dexamethasone adrenal suppression, and both had mild hypertension without hypokalemia. To study this apparent end-organ resistance to cortisol, we examined the glucocorticoid receptors in peripheral mononuclear cells. Using whole cell assays, glucocorticoid receptors in both patients were found to have reduced total binding capacity. We conclude that these two patients, members of the same family, have primary cortisol resistance accompanied by a reduced number of glucocorticoid receptors.

Steroidogenic effect of ent-kaur-16-en-15 beta-ol (kaurenol) on isolated rat adrenal cells.

In an in vitro bioassay system for adrenocorticotropic hormone using isolated rat adrenal cells, kaurenol, a diterpene alcohol, stimulated corticosterone production and augmented the steroidogenic effect of adrenocorticotropin or forskolin, dose-dependently. Kaurenol had no effect on cyclic AMP production by the cells. The diterpene also had no stimulatory effect on the adrenal adenylate cyclase activity in a cell free system. The results suggest that this particular diterpene exerts a steroidogenic effect through a mechanism independent of cyclic AMP generation.

Induction of differentiation of human phaeochromocytoma cells in culture by epidermal growth factor and insulin.

A primary culture of malignant phaeochromocytoma cells obtained from a left adrenal tumor of a 56 year old woman complaining of occasional palpitation and headache was established. The addition of epidermal growth factor (EGF) and insulin to the culture medium induced a profound development of network formation of axon-like processes. At the same time, the secretion of catecholamines from cultured cells was also increased. EGF and insulin were demonstrated to induce the differentiation of malignant phaeochromocytoma cells in primary culture.

Rounding of cultured human carcinoid tumor cells by forskolin.

A primary culture of carcinoid cells obtained from a metastasized brain tumor of a 30 year old man was established. Rounding of carcinoid cells was induced by the addition of 20 microM forskolin or 1 mM dibutyryl cyclic AMP to the culture medium. The cyclic AMP content in carcinoid cells was increased thirtyfold by the addition of 20 microM forskolin. The results provided evidence that cyclic AMP might also be involved in rounding of human malignant carcinoid cells.

Elevated serum lipoprotein (a) levels associated with ulcerative colitis in a young Japanese patient.

Thromboembolism has been shown to play a role in the pathogenesis of inflammatory bowel disease (IBD). A possibility exists that lipoprotein (a) [Lp(a)], a newly-discovered prothrombotic factor, also participates in the development of at least some cases of IBD. Marked elevation of serum Lp(a) levels was observed in a young patient with ulcerative colitis. A biopsy specimen of the rectal mucosa showed findings compatible with ulcerative colitis, as well as small vessel thrombus occurring within the muscularis mucosa in the rectum. Serum Lp(a) levels were markedly elevated on admission (71 mg/dl), with a gradual decrease to 46 mg/dl on discharge. Moreover, serum Lp(a) levels decreased in parallel with clinical improvement. In the quiescent clinical stage, no small vessel thrombus was observed in the mucosa on follow-up colonoscopy. The association between IBD and hyper-Lp(a)-emia would be presumable but it has been, to our knowledge, previously unreported. The case reported here would be the first young patient, suggesting the presence of hyper-Lp(a)-emia and small vessel thrombus formation occurring in association with the development of ulcerative colitis.

Familial renal hypouricemia with intact reabsorption of uric acid.

Three patients with renal hypouricemia in the same family are described. Serum urate levels in the mother were in the low normal range and were below normal in her 2 sons. In all 3 patients, the ratios of renal urate clearance to creatinine clearance were abnormally elevated. Clear responses to either pyrazinamide or probenecid administration were observed in these ratios. These results suggest that these 3 patients had renal hypouricemia with normal reabsorption of urate as judged by the criteria for differentiating abnormalities in renal urate handling. This corresponds to the previously postulated mechanism as renal urate hypersecretion. Possible limitations to the diagnostic use of probenecid and pyrazinamide are also discussed.

Actions and interactions of glucocorticoids and transforming growth factor beta on two related human myeloma cell lines.

To evaluate possible involvement of a paracrine/autocrine inhibitory growth factor in myeloma cell growth, we studied the expression and actions of two forms of transforming growth factor beta (TGF-beta 1 and TGF-beta 2) on two closely related myeloma cell lines, OPM-1 and OPM-2. Earlier studies showed that both cell lines contain glucocorticoid receptors, but only OPM-2 cells are growth inhibited by dexamethasone (Dex). We found that OPM-2 growth was inhibited by TGF-beta, with TGF-beta 1 exerting a greater effect than TGF-beta 2, and Dex plus TGF-beta 1 acting synergistically. In OPM-1 (Dex insensitive), TGF-beta mRNA was not expressed, whereas it was induced by Dex in OPM-2. It was also possible to block partially the growth inhibition of Dex in OPM-2 cells by the addition of anti-TGF-beta 1 antibodies. These data suggest that the glucocorticoid effect(s) on myeloma cells may be mediated at least in part through modulation of internal and/or external levels of TGF-beta 1.

Optical stabilizer using a bistable optical device with a PMN electrostrictor.

An optical stabilizer utilizing the higher-order stable state of a Fabry-Perot resonator bistable optical device has been made using a PMN electrostrictor with a high bias voltage. The output power of this device exhibits bistable behavior with high reproducibility and is nearly constant over a wide range of input power. Light intensity fluctuation of the laser source can be reduced to ~1/150 by using this optical stabilizer.