Effects of Different Serum on in vitro Cultured Human Granulosa Cells

Objective To evaluate the effects of different sera on the growth of human granulosa cells （GCs） cultured in vitro. Methods GCs were obtained from women who underwent follicular aspirates during in vitro fertilization （IVF） program. Five groups were divided according to media supple- mented with different types of sera. Group A, 10% heat-inactivated fetal bovine serum （FBS）; group B, 10% heat-inactivated newborn bovine serum; group C, 10% non heat-inactivated FBS; group D, 10% human serum; group E, bovine serum albumin. Morphological characteristics and viability of GCs measured by trypan blue exclusion assay were evaluated after 24 h of incubation.Results GCs cultured in group A and group B showed multiform morphology compared with other groups. GCs cultured in group D and group E were present with cytoplasmic atrophy and less pseudopodium. Moreover, group A and group B showed a similar level in the viability of GCs （P〉0.05）, which displayed no difference between group D and group E as well （P〉0.05）. Group C had a lower level of viability than group A （P〈0.05） but a higher level than group D （P〈0.01）. Conclusion Heat-inactivated sera can improve the growth of GCs. Different types of sera would have different effects on the growth of GCs cultured in vitro. The pre-culture with different types of sera should be performed to get better efficacy.

Effect of Dandelion Extracts on the Proliferation of Ovarian Granulosa Cells and Expression of Hormone Receptors

Background： In the current society, infertility related to age has become a social problem. The in vitro fertilization （IVF） success rate in women with poor ovarian response （POR） is very low. Dandelion extract T-1 （DE-T1） is an effective component of the extract from the leaves and stems of Traxacum officinale, which is one of the medicines used in some patients with POR, but its molecular mechanism remains unclear. Methods： Following IVF, ovarian granulosa cells （GCs） of sixty patients were extracted and divided into normal ovarian response （NOR） and POR groups. GCs were cultured in a dose-dependent and time-dependent manner with DE-TI, proliferation of GCs was determined by Cell Counting Kit-8 assay, and mRNA levels of insulin-like growth factor 1 receptor （IGF-1R）, luteotropic hormone receptor （LHR）, follicle-stimulating hormone receptor （FSHR）, LHR, and CYP19A1 （aromatase） were determined by quantitative polymerase chain reaction. Progesterone and estradiol （E2） concentrations were determined by enzyme-linked immunosorbent assay. Results： The cell viability gradually increased with the progressive increase in the DE-T1 concentration. Compared with the control group （without DE-T1）, the mRNA expressions of FSHR, LHR, IGF-IR, and CYPIgAI were upregulated after the addition of DE-T l, especially in the 2.5% DE-T 1 group （P 〈 0.01 ）. The expression of IGF- 1R was upregulated approximately 25 times （24.97 ± 4.02 times） in the POR group with 2.5% DE-T1. E2 and progesterone levels increased with the increasing DE-T1 concentration. There were highly significant differences in the E2 and progesterone secretion between the NOR and POR groups （P 〈 0.01）. Conclusion： DE-TI may promote steroid hormone synthesis by promoting GC proliferation and upregulating GC receptor expression, thereby improving ovarian endocrine function.

Effect of Metformin-Induced Stimulation on the Expression of Insulin Receptor Substrate 1 through Negative Regulation of P70S6k

Objective:The aim is to study the effects of metformin on the expression of 70 kDa ribosomal protein S6 kinase(P70S6k),insulin receptor substrate 1(IRS-1),and IRS-1Ser307 phosphorylation in human luteinized granulosa cells.Methods:Granulosa cells in the experimental group were cultured in M199 medium containing 0.1 mmol/L metformin for 24 h and those in control group were cultured in M199 medium.The expression levels of P70S6k and IRS-1 mRNA were detected by reverse-transcriptiom polymerase chain reaction(RT-PCR)and real-time PCR.P70S6k,IRS-1,p-ser307-IRS-1,and p-thr389-P70S6k protein expression levels were detected by immunofluorescence and western blotting.Results:P70S6k mRNA level was higher and IRS-1 was significantly lower in the experimental group than those in the control group.IRS-1 and p-ser307-IRS-1 were expressed in cell plasma,and P70S6k and p-thr389-P70S6k were expressed in cell nucleus.The results of Western blot analysis indicated that the expression levels of P70S6k,p-thr389-P70S6k,IRS-1,and p-ser307-IRS-1 proteins had significant difference between the experimental group and the control group.Compared to the control group,the relative intensity illustrated that the expression levels of P70S6K and p-thr389-P70S6k significantly increased in the experimental group;however,those of IRS-1 and p-ser307-IRS-1 proteins significantly decreased.Conclusion:Metformin can inhibit the P70S6k mRNA and protein expression levels in the granulosa cells and improve insulin sensitivity by regulating IRS-1 expression through Akt/P70S6k/IRS-1-dependent pathway.