Expression of mitochondrial transcription factor A in granulosa cells: implications for oocyte maturation and in vitro fertilization outcomes

OBJECTIVE

In vitro fertilization-embryo transfer (IVF-ET) is a widely used treatment for infertility, with oocyte maturation and quality having a significant impact on oocyte fertilization, embryo development, and fetal growth. Mitochondrial transcription factor A (TFAM) is essential for maintaining the mitochondrial oxidative respiratory chain and supplying energy for oocyte development, fertilization, and embryonic development. In this study, we aimed to examine TFAM expression in women undergoing IVF-ET and assess its impact on the IVF outcomes.

METHODS

We recruited 85 women who underwent IVF-ET treatment for infertility. On the date of egg collection, granulosa cells were extracted from the clear follicular fluid of the first mature egg using ultrasound-guided needle aspiration. The collected granulosa cells served three purposes: (1) detecting TFAM gene expression in granulosa cells via immunocytochemistry, (2) determining TFAM mRNA expression using reverse transcription-PCR (RT-PCR), and (3) measuring TFAM protein expression through western blotting.

RESULT

Based on the results, we found that TFAM was localized and expressed in the cytoplasm of granulosa cells, whereas no expression was detected in the nucleus. Granulosa cells exhibited a linear correlation between TFAM mRNA and TFAM protein expression. The study participants were divided into three groups using the ternary method based on relative TFAM mRNA expression thresholds of 33% and 76%: the low-expression group (n = 30), the moderate-expression group (n = 27), and the high-expression group (n = 28). When compared to the other two groups, the moderate expression group exhibited a significantly higher egg utilization rate, 2 pronucleus rate, fertilization rate, and clinical pregnancy rate (P < 0.05).

CONCLUSION

TFAM was detected in the cytoplasm of human ovarian granulosa cells. Women with moderate TFAM expression demonstrate enhanced outcomes in IVF.

Brocazines A-F, Cytotoxic Bisthiodiketopiperazine Derivatives from Penicillium brocae MA-231, an Endophytic Fungus Derived from the Marine Mangrove Plant Avicennia marina

Six new disulfide-bridged diketopiperazine derivatives, brocazines A-F (1-6), along with one known analogue (7), were isolated and identified from the cytotoxic extract of Penicillium brocae MA-231, a fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these compounds were established on the basis of detailed interpretation of NMR and mass spectroscopic data. X-ray crystallographic analysis confirmed the structure of 1 and established the structure and absolute configuration of 5, while the absolute configurations for compounds 1, 4, and 6 were deduced by comparison of the CD data with those of 5. Compounds 1, 2, 5, and 6 showed cytotoxic activities against several tumor cell lines.

Targeted induction of apoptosis in glioblastoma multiforme cells by an MRP3-specific TRAIL fusion protein in vitro

Single-chain Fv fragments (scFvs) consist of the variable heavy-chain (VH) and variable light-chain (VL) domains, which are the smallest immunoglobulin fragments containing the whole antigen-binding site. Human soluble tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) proves to acquire a potent pro-apoptotic activity only after selective binding to a predefined tumor cell surface antigen and has no off-target effects towards normal cells. Glioblastoma multiforme (GBM) is the most frequent and aggressive type of brain tumor and overexpresses human multidrug resistance protein 3 (MRP3). In this study, we designed a novel fusion protein, termed scFvM58-sTRAIL, in which the MRP3-specific scFv antibody M58 was genetically fused to the N-terminus of human soluble TRAIL (sTRAIL). The recombinant scFvM58-sTRAIL fusion protein, expressed in Escherichia coli, was purified by chromatography and tested for cytotoxicity. scFvM58-sTRAIL showed a significant apoptosis-inducing activity towards MRP3-positive GBM cells in vitro. The pro-apoptotic activity of scFvM58-sTRAIL towards GBM cells was strongly inhibited in the presence of the parental scFvM58 antibody, suggesting that cytotoxic activity is MRP3-restricted. In a control experiment with MRP3-negative Jurkat cells, scFvM58-sTRAIL did not induce apparent apoptosis. In addition, through target antigen-restricted binding, scFvM58-sTRAIL was capable of activating not only TRAIL-R1 but also TRAIL-R2. In conclusion, our results suggest that fusion protein scFvM58-sTRAIL with specificity for MRP3 is a highly selective therapeutic agent and may provide an alternative therapy for human GBM.

Sulfur-containing cytotoxic curvularin macrolides from Penicillium sumatrense MA-92, a fungus obtained from the rhizosphere of the mangrove Lumnitzera racemosa

Sumalarins A-C (1-3), the new and rare examples of sulfur-containing curvularin derivatives, along with three known analogues (4-6), were isolated and identified from the cytotoxic extract of Penicillium sumatrense MA-92, a fungus obtained from the rhizosphere of the mangrove Lumnitzera racemosa . Their structures were established by detailed interpretation of NMR and MS data, and compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1-3 and 5 showed potent cytotoxicity against some of the tested tumor cell lines. Sulfur substitution at C-11 or a double bond at C-10 significantly increased the cytotoxic activities of the curvularin analogues.