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Abstract Background Zucker fatty (fa/fa) rats are a well-understood model of obesity and hyperinsulinemia. It is now thought that obesity/hyperinsulinemia is an important cause of endocrinological abnormality, but to date there have been no reports on the changes in ovarian morphology or the ovarian androgen profile in rat models of obesity and insulin resistance. Methods In this study we investigated the effects of obesity and hyperinsulinemia on ovarian morphology and the hormone profile in insulin-resistant Zucker fatty rats (5, 8, 12 and 16 weeks of age, n = 6-7). Results Ovaries from 5-week-old fatty rats had significantly greater total and atretic follicle numbers, and higher atretic-to-total follicle ratios than those from lean rats. Ovaries from 12- and 16-week-old fatty rats showed interstitial cell hyperplasia and numerous cysts with features of advanced follicular atresia. In addition, serum testosterone and androstenedione levels significantly declined in fatty rats from age 8 to 16 weeks, so that fatty rats showed significantly lower levels of serum testosterone (12 and 16 weeks) and androstenedione (all weeks) than lean rats. This may reflect a reduction of androgen synthesis during follicular atresia. Serum adiponectin levels were high in immature fatty rats, and although the levels declined significantly as they matured, it remained significantly higher in fatty rats than in lean rats. On the other hand, levels of ovarian adiponectin and its receptors were significantly lower in mature fatty rats than in lean mature rats or immature fatty rats. Conclusions Our findings indicate that ovarian morphology and hormone profiles are significantly altered by the continuous insulin resistance in Zucker fatty rats. Simultaneously, abrupt reductions in serum and ovarian adiponectin also likely contribute to the infertility seen in fatty rats.

The implication of membrane localization of target mRNA in the action of a small RNA is studied in the context of the mechanism of post-transcriptional regulation of glucose transporter in Escherichia coli. It can be concluded that the mRNA localization to the inner membrane coupled with the membrane insertion of nascent peptide is responsible for mediating the Hfq/ small antisense RNA- (SgrS) dependent ptsG mRNA destabilization and reducing second rounds of translation.

This report presents an unusual case of Sertoli-stromal cell tumor and polycystic ovary syndrome successfully treated with weight reduction and an insulin-sensitizing agent. A 22-year-old woman, gravida 0, para 0, visited our hospital for the first time with a 12-year history of secondary amenorrhea and hypertrichosis. Transvaginal ultrasonography revealed a solid tumor in the right ovary. Right salpingo-oophorectomy was performed and pathological examination confirmed a Sertoli-stromal cell tumor. The patient's serum androgen levels declined postoperatively, but remained above normal. Pioglitazone treatment for 6 months also significantly reduced serum androgen levels, but they still remained above normal. However, after losing 12 kg of body weight, the patient's serum androgen levels declined to normal, and spontaneous menstruation became regular. Weight reduction with pioglitazone is an effective means of treating hyperandrogenism. [ABSTRACT FROM AUTHOR]

Context: Follicle-stimulating hormone (FSH)-secreting pituitary adenoma is usually a nonfunctioning tumor, but in rare cases it may develop into ovarian hyperstimulation. Several reports have revealed that serum FSH levels are normal to slightly high in patients with combined FSH-secreting pituitary adenoma with ovarian hyperstimulation. This finding is different from iatrogenic ovarian hyperstimulation syndrome (OHSS), which is associated with extremely high levels of FSH. Objective: To describe the clinical course of two patients who developed OHSS from FSH-secreting pituitary adenoma. Results: Endocrine studies of the two cases revealed that FSH levels were normal or slightly increased, but luteinizing hormone levels were low to undetectable. Their estradiol (E2) levels were intriguing: levels fluctuated drastically over 6 weeks in Case 1, but stayed flat in Case 2. Ultrasonographic examinations showed bilaterally enlarged multicystic ovaries, and magnetic resonance imaging indicated pituitary tumors. Transsephenoidal resection of the tumors ameliorated the symptoms and pathological diagnosis revealed FSH-secreting pituitary adenomas. Conclusion: As is not the case in iatrogenic OHSS, even a small to moderate amount of FSH stimulation, which is continuously secreted by a pituitary adenoma, can cause ovarian hyperstimulation. Although FSH-secreting pituitary adenoma can cause ovarian hyperstimulation, an extremely high amount of E2 biosynthesis from granulosa cells seldom occurs. [ABSTRACT FROM AUTHOR]

Background: Zucker fatty (fa/fa) rats are a well-understood model of obesity and hyperinsulinemia. It is now thought that obesity/hyperinsulinemia is an important cause of endocrinological abnormality, but to date there have been no reports on the changes in ovarian morphology or the ovarian androgen profile in rat models of obesity and insulin resistance. Methods: In this study we investigated the effects of obesity and hyperinsulinemia on ovarian morphology and the hormone profile in insulin-resistant Zucker fatty rats (5, 8, 12 and 16 weeks of age, n = 6-7). Results: Ovaries from 5-week-old fatty rats had significantly greater total and atretic follicle numbers, and higher atretic-to-total follicle ratios than those from lean rats. Ovaries from 12- and 16-week-old fatty rats showed interstitial cell hyperplasia and numerous cysts with features of advanced follicular atresia. In addition, serum testosterone and androstenedione levels significantly declined in fatty rats from age 8 to 16 weeks, so that fatty rats showed significantly lower levels of serum testosterone (12 and 16 weeks) and androstenedione (all weeks) than lean rats. This may reflect a reduction of androgen synthesis during follicular atresia. Serum adiponectin levels were high in immature fatty rats, and although the levels declined significantly as they matured, it remained significantly higher in fatty rats than in lean rats. On the other hand, levels of ovarian adiponectin and its receptors were significantly lower in mature fatty rats than in lean mature rats or immature fatty rats. Conclusions: Our findings indicate that ovarian morphology and hormone profiles are significantly altered by the continuous insulin resistance in Zucker fatty rats. Simultaneously, abrupt reductions in serum and ovarian adiponectin also likely contribute to the infertility seen in fatty rats. [ABSTRACT FROM AUTHOR]

The relationship between serum levels of beta-trace protein (BTP) or serum creatinine (s-Cr) and the prognostic stages of type 2 diabetic nephropathy was determined. Serum samples from 174 patients with type 2 diabetes were obtained from Juntendo University Hospital, Tokyo, and Juntendo Urayasu Hospital, Chiba, Japan. They were classified into four groups according to the Report of the Ministry of Health and Welfare of Japan (1991, p 251-256) as follows: Stage I (normoalbuminuric stage), Stage II (microalbuminuric stage), Stage IIIA (macroalbuminuric stage without renal dysfunction), Stage IIIB (macroalbuminuric stage with renal dysfunction), and Stage IV (renal failure stage). Among these patients, 68 were Stage I, 29 Stage II, 32 Stage IIIA, 17 Stage IIIB, and 28 Stage IV. Levels of serum BTP were measured using the nephelometric assay on a BNA II analyzer (Dade Behring Diagnostics, Marburg, Germany). The mean levels of serum BTP in Stage IIIA were significantly higher than those in Stage I or II (P < 0.00001, P < 0.002, respectively). However, the mean levels of s-Cr in Stage IIIA were not significantly higher than that in Stage I or II. In conclusion, serum BTP was a good marker for the identification of early renal impairment in type 2 diabetes., (Copyright 2004 Wiley-Liss, Inc.)