The effects of recombinant luteinizing hormone (rLH) and recombinant follicle stimulating hormone (rFSH) both separately and together were analysed on the in-vitro maturation of a well-defined class of mouse early preantral follicles. Metaphase-II (MII) oocytes were only obtained when rLH or rFSH or a combination of both hormones was added to a standard rich culture medium at constant doses throughout the culture period. Without gonadotrophins only 8% of the follicles reached day 12 of culture. Follicle survival was optimal (between 90 and 100%) when rFSH was used; significantly fewer follicles were kept intact when rLH was added as the only supplement (54%; P < 0.001). Theca cells played a fundamental role in follicle survival when rLH was the only supplement. Presence of rLH significantly influenced the formation of antral-like cavities: on day 12, 59% of follicles cultured with rLH + rFSH had a large cavity, as compared with only 21% in cultures with rFSH only (P < 0.0001). The rHCG stimulated germinal vesicle breakdown rate from the different gonadotrophin-supplemented cultures on day 12 was not significantly different (FSH: 89%; LH: 70%; FSH/LH: 83%). However, addition of rLH to rFSH did significantly improve (P < 0.05) the completion of the first meiotic division up to the MII stage (FSH: 46%; LH: 39%; FSH/LH: 76%). Interfollicle differences in steroid production were very large and depended on the presence of theca cells and on the kind of gonadotrophin supplemented. Without theca cells, oestrogen concentrations in rFSH-supplemented cultures were 100 times lower than their theca-containing counterparts during the entire culture period. From culture day 9 onwards most conditioned media had increased basal progesterone concentrations. This study points up the in-vitro role of LH on the differentiation of follicle-like structures and the oocyte's meiotic maturation and suggests an important role for theca cells in providing modulators of in-vitro gonadotrophin action.

No abstract

To assess their quality, spindles were analysed in mouse oocytes from pre-antral follicle culture. High or low oxygen tension was present during the last 16 or 20 h post human chorionic gonadotrophin (HCG)/epidermal growth factor (EGF) addition. Most oocytes from pre-antral follicle culture possessed typical anastral spindles with flat poles resembling those of ovulated, in-vivo-matured oocytes of sexually mature mice, while denuded oocytes in-vitro matured to metaphase II (MII) formed significantly longer, slender spindles with pointed, narrow poles. Spindles in oocytes from follicle culture were only slightly shorter and less compact at the equator as compared with those of oocytes matured in vivo. Chromosomes were well aligned at the equator in MII oocytes obtained from follicle culture with high oxygen. Maturation rate was significantly reduced by lowering oxygen tension to 5% O2. Prolonged culture and the presence of only 5% O2 dramatically increased the percentage of MII oocytes with unaligned chromosomes. These observations indicate that sufficient oxygen supply and time of retrieval after initiation of resumption of maturation by HCG as well as the microenvironment and cell-cell interactions between oocytes and their somatic compartment are critical in affecting the oocyte's capacity to mature to MII, to form a functional spindle, and to align chromosomes correctly.

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In vivo studies on folliculogenesis have documented a relation among intrafollicular steroid content, follicle growth, and oocyte development. This study examined how profound changes in androgen/estrogen ratio would affect mouse in vitro follicular development. Arimidex, a potent follicular aromatase inhibitor was used for this purpose. Early preantral follicles were cultured for 12 days up to the preovulatory stage. Oocyte's meiotic maturation, spindle and chromosome configurations, in vitro fertilization and preimplantation embryo development were evaluated. Compared to controls, Arimidex reduced E2 concentration in follicle culture medium by a factor 1000, and an expected simultaneous accumulation of testosterone was measured in the conditioned medium. Arimidex treatment provoked a dose-dependent earlier differentiation of the granulosa cells as judged by an earlier antrallike cavity formation and slightly elevated basal progesterone secretion. Follicle survival exceeded 98% in all groups and all follicles responded normally to HCG/EGF addition on day 12 by cumulus mucification. By the HCG ovulatory challenge, progesterone output was reduced in Arimidex supplemented groups suggesting preovulatory luteinization. These results indicate that in vitro mouse follicles can develop normally under very low levels of estrogens and that a local androgen increase by a factor 3 is not atretogenic. Oocyte growth did not differ among culture conditions. Arimidex treatment induced a dose dependent enhancement of GVBD and polar body formation rate in response to HCG at the end of culture. Spindle and chromosome analyses demonstrated that in all groups, 90% of the oocytes which extruded a polar body had also reached the MII stage. While most of the cultured MII oocytes had a normal spindle and well aligned chromosomes, significantly less oocytes were fertilized in the groups cultured in the presence of Arimidex. Once fertilized, however, there was found to be no difference for preimplantation embryo development between controls and Arimidex treatment. These data suggest that in mice a pronounced estrogenic environment is not essential for in vitro folliculogenesis. Drastic changes in the intrafollicular steroid concentrations do not disrupt meiotic maturation nor compromise early preimplantation development, but adversely affect fertilization of in vitro grown oocytes.

Using a mouse early preantral follicle culture system, mature full grown oocytes, arrested in prophase I of meiosis, were produced after 12 days using a recombinant gonadotrophin-supplemented medium. This culture medium does not mimic the normal extracellular environment of the oocyte and might therefore modify meiotic regulation and more particularly progression to metaphase II (MII). The aim of this study was to optimize the treatment using recombinant stimulatory ligands which were known to induce germinal vesicle breakdown (GVBD) and completion of meiosis I, metaphase II (MII), namely recombinant follicle stimulating hormone (r-FSH), chorionic gonadotrophin (r-HCG) and epidermal growth factor (EGF). Full-grown intrafollicular oocytes could not resume meiosis when the 'ovulatory' stimulus was r-FSH, used at a 100 times higher dose than during culture. r-FSH did not increase progesterone production. When 1.5 IU/ml r-HCG was used as meiotic trigger, germinal vesicle breakdown was obtained in 95% of the oocytes 64% of which extruded a first polar body. r-HCG induced a dramatic increase in progesterone production. When EGF was administered as sole stimulus on day 12 to the attached follicle-enclosed oocytes, only doses > or =5 ng/ml could cause GVBD, although less effectively than r-HCG (45 versus 95%; P < 0.0001). Oocytes undergoing GVBD by the EGF pulse reached metaphase II at a rate of 54% (not significant versus r-HCG). EGF did not stimulate progesterone production. Addition of increasing doses of EGF (0.5; 5; 10; 50 ng/ml) to r-HCG did not increase the GVBD-rate, but EGF doses >5 ng/ml improved MI to MII transition (P=0.027), thereby improving the final yield of MII oocytes by 12.5%. These data show that up to a dose of 50 ng/ml, EGF on its own could only override the somatic inhibitory stimuli in less than half of the cultured follicles. However, in addition to HCG, EGF (25 ng/ml) had a stimulatory effect on completing the first meiotic division. It was concluded that, under the present culture conditions, EGF in combination with HCG provided optimal nuclear maturation.

No abstract

The antidepressive effects of the antidiabetic medicine, pioglitazone, were recently reported in several studies. These effects may ameliorate the depressive symptoms of patients with post-stroke depression (PSD). The present study aimed to evaluate the antidepressive effect of pioglitazone in patients with PSD combined with type 2 diabetes. A total of 118 consecutive patients with stroke who had depression were studied for an average of 3 months. The Diagnostic and Statistical Manual of Mental Disorders (fourth edition) was used to assess whether a patient was depressed or not. The severity of depression was evaluated by the Hamilton depression rating scale (HAMD). In accordance with their HAMD scores, the 118 patients were divided into a severe depression group (n=40) and a mild and moderate (MM) depression group (n=78). These subjects were then divided into pioglitazone [30 mg once daily (qd)] and metformin (0.5 g twice daily) subgroups. All patients were given fluoxetine (20 mg qd). Follow-up evaluations, which included HAMD scores, activities of daily living (ADL) scores, fasting blood glucose (FBG) levels and fasting insulin (FINS) levels, were conducted on the first and third month following the beginning of the treatment. In the MM depression group, the HAMD score in the pioglitazone subgroup was lower than that in the metformin subgroup following treatment for 1 or 3 months. In the severe depression group, the HAMD score in the pioglitazone subgroup was lower than that in the metformin subgroup following 3 months of treatment. The FINS levels of the pioglitazone subgroup gradually decreased in the 3 months of treatment. No noticeable improvement was observed in the ADL scores and FBG values. In conclusion, the results of the current study demonstrate that pioglitazone effectively decreased HAMD scores and FINS values in patients with PSD, suggesting that pioglitazone may be useful for the treatment of patients with PSD combined with type 2 diabetes.