Osteoporosis is the most common complication of Cushing’s syndrome. We retrospectively examined the prevalence and risk factors for osteoporosis in 42 female patients with Cushing’s syndrome. Osteoporosis and atraumatic fractures were assessed by bone mineral density of the lumbar vertebral spine (L2-L4) using dual energy X-ray absorptiometry (DXA) and X-ray examination. The prevalence of osteoporosis and fracture were 54.8% and 21.4%, respectively. The prevalence of osteoporosis (69.6% vs. 37.8%) and atraumatic bone fracture (26.1% vs. 15.8%) were significantly higher in patients with adrenal Cushing’s than in those with pituitary Cushing’s. AP and lateral BMD was significantly higher in patients with pituitary origin than in those with adrenal origin. Among several variables examined by multiple logistic regression, the etiology of Cushing’s syndrome (adrenal vs. pituitary origin) was a significant factor affecting the prevalence of osteoporosis. Neither age, body mass index, duration of amenorrhea, nor extent of hypercortisolism were significant factors in this analysis. Plasma DHEA-S and urinary 17-KS excretion were significantly higher in pituitary Cushing’s than in adrenal Cushing’s. The present study shows that the prevalence of osteoporosis in patients with Cushing’s syndrome is influenced by its etiology. A factor associated with pituitary Cushing’s syndrome, such as adrenal androgen, may protect these patients from glucocorticoid-induced osteoporosis.
To elucidate its effect on proinsulin processing, we introduced the expression of a Pittsburgh type-mutant, α1-protease inhibitor M/R (α1-PIM/R) and its chimera protein with growth hormone (GH) (GHα1-PIM/R) into MIN6 cells. In metabolic labeling and chasing experiments with [3H]-Leu and [35S]-Met, proinsulin appeared in the medium during stimulatory secretion only from MIN6 clones expressing GHα1-PIM/R and, surprisingly, α1-PIM/R, but not from the clones of either the control or α1-PI. The major part of α1-PIM/R was secreted through the constitutive pathway and about 10% of total secreted α1-PIM/R in the chase periods entered the regulated pathway. On the other hand, GHα1-PIM/R was mainly transported to the secretory granules and about 80% of the total secreted GHα1-PIM/R in the chase periods was secreted during stimulatory secretion. In the first 3 h chase periods without stimulation, only α1-PIM/R and no GHα1-PIM/R appeared in the medium, thus suggesting that α1-PIM/R might be transported through a constitutive-like pathway for those periods. The α1-PI, which had no inhibitory effect on proinsulin processing, showed similar secretion pathways to those of α1-PIM/R. This implies that some part of α1-PIM/R and α1-PI entered the regulated pathway, not due to any specific interaction between the processing endoproteases and serine protease inhibitors, but due to some type of passive transport in a nonselective manner. The inhibitory effect of α1-PIM/R in the regulated secretory pathway was slightly but clearly evident when it was expressed in MIN6 β-cells.
We reported previously that acute stress and intracerebroventricular (ICV) injection of corticotropin-releasing factor (CRF) increased neuronal activation and CRF type-1 receptor (CRFR-1) mRNA expression in the CRF-producing neurons of the parvocellular paraventricular nucleus (PVN) of the hypothalamus. In this study, to determine whether CRF can act directly on hypothalamic CRF neurons, thereby increasing CRFR-1 expression, microinjection of CRF into PVN neurons in vivo and primary cultures of dispersed rat fetal hypothalami in vitro were performed. Microinjection of 0.1 μg of CRF into the PVN significantly increased c-fos and CRFR-1 mRNA expression in the CRF-producing parvocellular PVN, 30 min or 180 min after injection, respectively. This effect was blocked by a CRF antagonist, α-helical CRF. CRF, when injected into the lateral ventricle at the same dose, increased neither CRFR-1 nor c-fos mRNA levels in the PVN. Primary culture of hypothalamic neurons revealed that CRFR-1 like immunoreactivity was located in CRF-containing neurons, and that the CRFR-1 mRNA level was significantly increased 4 h after incubation with 10-8 M CRF. These results demonstrate that CRF directly affects hypothalamic neurons to increase CRFR-1 mRNA expression, providing evidence of a direct role for CRF in the regulation of CRFR-1 expression of hypothalamic neurons.
The purpose of the present study was to investigate the role of pineal gland (melatonin) on parturition time, luteal function, and fetal growth in pregnant rats. Cycling rats were subjected to pinealectomy or sham operation under ether anesthesia; and pinealectomized rats immediately underwent implantation of a melatonin capsule (PINX + Mel group) or a vehicle-containing capsule (PINX group), and sham operated rats also underwent implantation of a vehicle-containing capsule (control group). All rats were maintained under the same photoperiod conditions (14 L : 10 D) and were induced pregnancy. Blood samples were obtained on days 7, 12, 15, 17, 19, and 21 of pregnancy to measure serum progesterone concentrations, and parturition times were recorded on days 22 and 23. In the next experiment, pregnant PINX rats received subcutaneous injection of melatonin (10 μg/body) at 08:00 h (PINX + 8 h group) or at 20:00 h (PINX + 20 h group) from day 15 to the end of pregnancy, and parturition times were recorded. Parturition times of rats in the PINX group, the PINX + Mel group or the PINX + 8 h group, but not the PINX + 20 h group, were significantly different compared with those in the control group. Pinealectomy or melatonin implantation did not affect serum progesterone concentrations during pregnancy or the number and weight of fetuses or corpora lutea. The present results indicate that pineal gland (melatonin rhythm) synchronizing with photoperiodic rhythm is likely to be an important determinant of parturition time, but it does not affect progesterone production or fetal growth in pregnant rats.
Although many researchers have reported clinical and laboratory parameters for prediction of remission in Graves’ disease during or after anti-thyroid drug therapy, there is no reliable one to assure the complete remission. We prospectively examined a practical therapy with minimum maintenance dose of anti-thyroid drugs for prediction of remission in Graves’ disease. Fifty-seven patients with Graves’ disease were treated with anti-thyroid drugs at the initial dose of 30 mg/day of methimazole (MMI) or 300 mg/day of propylthiouracil (PTU). Then, doses were gradually decreased, and finally discontinued when the patients were able to maintain euthyroid (normal FT4 and TSH) for at least 6 months with the minimum maintenance dose (MMI 5 mg every other day or PTU 50 mg every other day). After discontinuation of drugs, FT4, FT3, TSH and TSH-binding inhibitory immunoglobulin (TBII) were measured every one to two months for the first 6 months and every 3-4 months for the next 18 months to confirm continuous remission. After 2 years of drug cessation, 46 (81%) of 57 patients were in remission and the other 11 patients had relapsed into thyrotoxicosis. At the time of drug discontinuation, the serum concentration of FT4, FT3 and TSH, titers of anti-thyroglobulin antibodies and anti-thyroid microsomal antibodies, goiter size were not different between the remission and relapse groups. At the time of drug cessation, the activities of TBII and thyroid-stimulating antibodies (TSAb) overlapped between the two groups, although they were significantly lower in the remission group than in the relapse group (p<0.01). Forty percent (4/10) of TBII positive patients and 71% (23/32) of TSAb positive patients continued to be in remission. On the other hand, thyrotoxicosis relapsed in 5 (11%) of 47 TBII negative and 2 (8%) of 25 TSAb negative patients. These data indicate that minimum maintenance therapy to keep euthyroid (normal FT4 and TSH) for 6 months is a practical measure for 81% prediction of remission in Graves’ disease. The measurement of TBII or TSAb gave little additional information for predicting remission.
Hormone replacement therapy (HRT) has antiatherosclerotic effects of which the mechanism remains unclear. The ingestion of fish oil or other sources of n-3 polyunsaturated fatty acids has been included in comprehensive strategies to prevent atherosclerosis. Many epidemiologic studies have shown that the dietary intake of docosahexaenoic acid and eicosapentaenoic acid has antiatherosclerotic effects. We investigated the effect of HRT on plasma docosahexaenoic acid and eicosapentaenoic acid concentrations in postmenopausal women. Fifty-nine postmenopausal women, who received conjugated estrogens (0.625 mg/day) and medroxyprogesterone (2.5 mg/day) for 12 months, and 45 control postmenopausal women, who did not receive HRT, volunteered to participate in this study. Plasma docosahexaenoic acid and eicosapentaenoic acid concentrations were measured at baseline and at 6 and 12 months after the start of HRT. HRT significantly increased the plasma docosahexaenoic acid and eicosapentaenoic acid concentrations from 134 ± 5 μg/ml and 69 ± 4 μg/ml at baseline to 156 ± 7 μg/ml and 85 ± 7 μg/ml after 12 months (both p<0.01). However, the control group showed no significant change in their plasma docosahexaenoic acid and eicosapentaenoic acid levels during the study. HRT increased plasma docosahexaenoic acid and eicosapentaenoic acid levels in postmenopausal women. We propose that the increase in docosahexaenoic acid and eicosapentaenoic acid may be partially responsible for the beneficial mechanisms by which HRT induces an antiatherosclerotic effect in postmenopausal women.
This study investigates whether urinary levels of pentosidine, pyrraline and acrolein adduct are increased in type 2 diabetes (DM), and whether these levels are correlated with glycemic control and clinical traits. Urinary levels of pentosidine, pyrraline and acrolein adduct in DM patients (n = 100) recruited from the outpatient clinic of our university hospital were compared with those of age- and sex-matched non-diabetic subjects(n = 50). The correlation of these urinary levels with the glycemic control and the clinical traits were examined. Furthermore, the influence of smoking habit on the levels of acrolein adduct was examined. Urinary levels of pentosidine, pyrraline and acrolein adduct were all significantly (p<0.001) higher in the DM group than in the non-DM group (pentosidine(log(pmol/mgCr)), 1.579 ± 0.147 vs 1.427 ± 0.142; pyrraline (log(nmol/mgCr)), 0.888 ± 0.402 vs 0.581 ± 0.336; acrolein adduct (log(nmol/mgCr)), 2.316 ± 0.221 vs 2.051 ± 0.201). Glycemic control parameters, such as fasting plasma glucose (FPG) and HbAlc, were significantly correlated with these urinary levels. Age was correlated with the urinary levels of pentosidine but not with those of pyrraline and acrolein adduct. The urinary albumin excretion rate did not correlate with any of these urinary levels. The levels of acrolein adduct were higher in the subjects with smoking habit than in those without the habit in the DM group as well as in the non-DM group (DM, 2.391 ± 0.230 and 2.212 ± 0.190, p = 0.0004; Non-DM, 2.120 ± 0.171 and 1.993 ± 0.206, p = 0.0503). The urinary levels of pentosidine, pyrraline and acrolein adduct were increased in DM and were significantly correlated with glycemic control levels. In addition, smoking habit seems to increase the urinary levels of acrolein adduct.
The effects of recombinant human growth hormone (rhGH) treatment for three years were compared in patients with achondroplasia (ACH) and hypochondroplasia (HCH), whose diagnosis had been confirmed by DNA analysis of the fibroblast growth factor receptor 3 gene. Height SDS (H-SDS) and height velocity SDS (HV-SDS) using the standard for ACH significantly improved during three-year treatment as compared with that before treatment in both ACH and HCH except HV-SDS in the third year. The improvement was much greater in HCH than in ACH. The mean increase H-SDS using the standard for ACH in three years in ACH (from −0.2 SD to 0.1 SD) is almost negligible but that in HCH (from 1.2 SD to 2.6 SD) can be estimated as effective clinically. It can be concluded short-term GH treatment in HCH is effective to increase growth rate and H-SDS, but it has little effect in ACH. Further studies would be required to confirm the other beneficial effects of GH treatment such as increase in bone mineral density in ACH and HCH and the effect on the final height.
Although a number of abnormalities in oncogenes have been reported in thyroid neoplasms, little information is available on the signal transduction pathway involved in neoplastic thyroid cell growth. Both p70S6 kinase (p70S6K) and Akt are kinases downstream of phosphatidylinositol 3 kinase (PI3K). These kinases are phosphorylated and activated by growth factors including IGF-1, EGF/TGF-α, and HGF in thyroid cells. Since the receptors for these growth factors are reportedly overexpressed in human thyroid cancer, we hypothesized that the PI3K-mediated signalings are overactivated in thyroid cancers. Tumorous and adjacent normal tissues of 20 patients with papillary thyroid cancer were obtained at surgery, and expression of p70S6K and Akt were measured by Western blot. Expression of the protein levels of p70S6K was increased in tumor tissues (T) compared to normal thyroid tissues (N), and expression of phosphorylated p70S6K was also significantly increased in tumor than in surrounding normal tissues. Overexpression of p70S6K in tumor tissues was further confirmed by immunohistochemistry. Strong immunoreactivity in the cytoplasm of thyroid cancer cells was seen in the majority of cases, whereas little immunoreactivity was found in the surrounding normal portion. Expression of phosphorylated Akt (pAkt) was also significantly higher in tumor tissues. Phosphorylation of Bad (pBad), a substrate of Akt, was also increased in the tumor tissues in association with activation of Akt, and the T/N ratio for pAkt positively correlated to the T/N ratio for pBad. The data presented here demonstrate that both p70S6K and Akt are activated in the majority of human papillary cancer cells. Activation of these signalings may be involved in the progression of papillary carcinoma by stimulating cell proliferation and/or preventing apoptosis.
To assess thyroid status among the schoolchildren around Semipalatinsk Nuclear Testing Site (SNTS), Kazakhstan, and to evaluate the current status of iodine deficiency in this area, we performed medical screening of schoolchildren in two villages, Kaynar and Karaul villages, East Kazakhstan Region, Republic of Kazakhstan, located within 100 km of SNTS. A total of 196 schoolchildren were chosen at random. Control groups comprised 250 schoolchildren from Nagasaki, an iodine-rich area, and 100 schoolchildren from Gomel, an iodine-deficient area contaminated by the Chernobyl Nuclear Power Plant accident. Ultrasound screening of thyroid revealed three cases of benign thyroid disease (two cases of goiter and one single cyst), but no cases suspicious of malignancy. The urinary iodine (UI) concentrations of subjects in Kaynar and Karaul ranged from 21.8 to 735.8 μg/L, 4.3% of whom showed low UI concentrations (<50 μg/L), compared with 0% in the Nagasaki group and 52% in the Gomel group. The median UI concentration in Kaynar and Karaul was 153.2 μg/L, which was significantly lower than that in Nagasaki (366.3 μg/L, p<0.0001) but higher than that in Gomel (47.3 μg/L, p<0.0001). In conclusion, there was a low incidence of morphological abnormalities in the thyroid, and no evidence for severe iodine deficiency among the Kazakhstani children studied. These results suggest that there is no transgenerational risk for schoolchildren born from parents irradiated as a result of tests carried out in SNTS.
Autosomal dominant hypocalcemia (ADH) caused by activating mutations of calcium-sensing receptor (CaSR) is characterized by hypocalcemia with inappropriately low concentration of PTH and relative hypercalciuria. Active vitamin D treatment often leads to nephrolithiasis and renal impairment in patients with ADH. However, differential diagnosis between ADH and idiopathic hypoparathyroidism is sometimes very difficult. Here, we report a mutation of CaSR and its functional property found in three generations of a Japanese family. The proband developed seizures at 7 days of age. His mother and elder sister were discovered to have hypoparathyroidism by family survey, but his father was normocalcemic. His grandfather developed heart failure and was found to have hypoparathyroidism. All affected members had been treated with active vitamin D3 and bilateral nephrolithiasis were detected in three of them. DNA sequencing revealed that all affected patients had a heterozygous mutation in CaSR gene that causes proline to leucine substitution at codon 221 (P221L). In vitro functional analysis of the mutant CaSR by measuring inositol 1,4,5-trisphosphate production in response to changes of extracellular Ca indicated that this mutation is an activating one and responsible for ADH in this family. Therefore, careful monitoring of urinary Ca excretion before and during treatment of PTH-deficient hypoparathyroidism is very important, and screening of CaSR mutation should be considered in patients with relative hypercalciuria or with a family history of hypocalcemia.
In order to analyze the structures of the 5′-untranslated region of estrogen receptor alpha (ERα) mRNA in human uterine endometrium (Em), total RNA from Em was analyzed by 5′-rapid amplification of the cDNA ends method with antisense primer located on exon 1 of human ERα gene. Three isoforms of 5′-RACE clones were obtained: ERα mRNAs containing exon (A) (the upstream region of exon 1), exon C, and exons F-E2 (we adopted the nomenclature of 5′-untranslated exons of the Gannon group). The results imply that the major isoforms of ERα mRNA expressed in Em are these three isoforms. Moreover, reverse transcription-polymerase chain reaction (RT-PCR) analysis was carried out on Em, ovary (Ov) and liver (Li) mRNAs to detect the novel isoforms of ERα mRNA in these tissues, using sense primers located on exons (A), B, C, F, and E1, and antisense primer located on exon 1. As a result, in addition to the previously reported ERα mRNA isoforms containing exons (A), B, C, F-E2 and E1-E2 on exon 1, we identified two novel isoform mRNAs in which exons F and E1 were directly spliced onto exon 1. Differential distributions of these isoforms of ERα mRNAs in Em, Ov and Li were demonstrated by RT-PCR-Southern blot analysis. These results, together with the previous reports by others, indicate that there are at least ten isoforms of ERα mRNA containing different 5′-untranslated regions, exons (A), B, C, D, T1-T2, T1, F-E2, F, E1-E2 and E1, expressed in human, and that these are involved in tissue specific expression of the gene.
Progesterone secreted from ovarian corpus luteum plays pivotal roles in endometrial differentiation, and local progesterone metabolism to regulate its concentration in endometrial tissues is essential for the successful implantation and maintenance of pregnancy. In this study, we evaluated the expression of mRNA for 20α-hydroxysteroid dehydrogenase (20α-HSD), a key enzyme which converts progesterone to a biologically inactive metabolite, in human endometrial tissues and cultured endometrial stromal cells as well as decidua and chorionic tissues of early pregnancy. The level of 20α-HSD mRNA expression in secretory phase endometrium was significantly higher than that in proliferative phase endometrium and chorionic tissues. The expression level in decidual tissue was also significantly higher than that in chorionic tissue. In cultured endometrial stromal cells, 20α-HSD mRNA expression was slightly enhanced at a lower progesterone concentration of 0.01 μmol/l, and an increase in its expression was significantly suppressed at higher concentrations of 1 μmol/l or greater. No effect on the gene expression was seen in cultured endometrial stromal cells with various concentrations of 17β-estradiol. These results suggest that progesterone itself contributes to the regulation of local progesterone concentration through 20α-HSD levels in endometrial stromal cells at peri-implantation periods.
The aim of this study was to compare two two-step assays, a new coated plate (CP) ELISA assay (TRAb ELISA) using purified porcine TSH-receptors (pTSH-R) and a coated tube assay (CT) using recombinant human TSH-receptors (hTSH-R) (DYNOR test TRAK human). The same serum samples were used for the determination by both assays in patients with 100 untreated Graves’ disease (GD), 30 silent thyroiditis (ST), 10 subacute thyroiditis (SAT) and 87 Hashimoto’s thyroiditis (HT). In sera from patients with untreated GD, pTBII and hTBII were positive in nearly all cases except the same one, whereas the thirty sera from the ST had positive values of pTBII in one case and of hTBII in 4 cases. In the one ST case of both pTBII and hTBII positive, hyperthyroidism developed following ST, although the remaining ST cases including the three hTBII-positive cases were not followed by hyperthyroidism after ST attack. A positive value of hTBII was observed in one of 10 patients with SAT, whereas none of them was pTBII positive. In the 87 patients with HT, positive values of pTBII were recognized in 9 patients, whereas hTBII is positive in 10 patients. Serum TSAb and TSBAb activities were analyzed in the hTBII positive 7 patients. As a result, TSAb was all positive except one and TSBAb positive in 4 cases. Since there is no significant difference in the sensitivity and specificity between the two assays in the differentiation of thyrotoxicosis as well as the frequency of finding positive values in patients with HT, it is reasonable to conclude that the clear advantage of sensitivity for clinical application in the new CP and CT assays may be derived from the coated plate or coated tube assay itself, which probably excludes the effect of anti-TSH antibodies and HAMA, and is unrelated to the use of human or porcine TSH-receptors.