ABSTRACT
BACKGROUND: Insulin is an essential factor that controls female reproductive system. Insulin signaling via Foxo1 and Akt1 can improve steroidogenesis, cell proliferation, and protein synthesis. We aimed to determine the effect of insulin on possible changes in gene expression, hormonal status, and histological aspects of the ovary following the induction of the animal model of polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: In this experimental study, 24 adult female NMRI mice weighing 25-30 g were randomly placed in three groups: control, PCOS (60 mg/kg dehydroepiandrosterone (DHEA) for 20 days, and PCOS+insulin (60 mg/kg DHEA for 20 days+100 µL insulin diluted in water twice a week for 30 consecutive days). Blood specimens were obtained from the heart and the serum levels of testosterone, progesterone, and estradiol were measured. Right, and left ovaries were removed for real-time polymerase chain reaction (PCR) and stereological study. RESULTS: DHEA injection significantly amplified the concentration of testosterone, progesterone, and estradiol. While insulin treatment amended the level of reproductive hormones. DHEA injection significantly reduced the expression levels of Irs1-4, Pdk1, Pi3k, and Akt1-3 and raised the expression level of Caspase-3. However, insulin administration amplified expression levels of Irs1-4, Pdk1, Pi3k, and Akt1-3, and reduced Caspase-3. The total volume of ovarian tissue in mice receiving DHEA significantly declined compared to the control group. Besides, a substantial decrease was detected in the number of ovarian antral, Graafian, and primordial follicles and also in the total number of corpus luteum following DHEA administration. Comparison of structural alterations in ovarian tissue between the PCOS+insulin and the PCOS groups displayed that insulin administration improved the total number of Graafian, primordial, and antral follicles and also corpus luteum. CONCLUSION: In general, short-term insulin treatment showed improvement in hormonal balance, folliculogenesis, and insulin resistance in the ovaries of the PCOS mice model.
ABSTRACT
Time-resolved spectroscopy and, in particular, transient absorption methods have been widely employed to study the dynamics of materials, usually achieving time resolution down to femtoseconds with measurement windows up to a few nanoseconds. Various techniques have been developed to extend the measurement duration up to milliseconds and beyond to permit probing slower dynamics. However, most of these either demand complicated and expensive equipment or do not provide broadband spectral coverage. This paper proposes a transient absorption technique in which an ultra-short pulse laser and a broadband incoherent continuous-wave light source are employed as pump and probe, respectively. Detection of the transient probe transmission is performed in a time-resolved fashion with a fast photodiode after a monochromator and the data is recorded with an oscilloscope. The time resolution is determined by the electronic bandwidth of the detection and acquisition devices and is â¼1 ns, with a measurement duration window of up to milliseconds and a spectral resolution of <2 nm covering from 0.4 to 2 µm. In addition, the setup can be employed to measure time- and spectrally-resolved photoluminescence.
