MicroRNA-7a2 Contributes to Estrogen Synthesis and Is Modulated by FSH via the JNK Signaling Pathway in Ovarian Granulosa Cells

MicroRNA-7a2 (miR-7a2) plays fundamental roles in the female reproductive axis, and estrogen is indispensable for maintaining ovary function. However, the interaction between miR-7a2 and ovarian function is unclear. The present study aimed to determine whether and how miR-7a2 functions in estrogen synthesis. Firstly, the results verified that miR-7a was highly expressed in ovarian granulosa cells. The knockout (KO) of miR-7a2 caused infertility and abnormal ovarian function in mice. Concomitantly, the Cyp19a1 expression and estrogen synthesis were significantly inhibited, which was validated in primary granulosa cells. The mice transplanted with miR-7a2 KO ovaries showed similar results; however, estrogen supplementation reversed infertility. In the in vitro experiment, follicle-stimulating hormone (FSH) significantly improved the expression of miR-7a and Cyp19a1 and the synthesis of estrogen. However, the miR-7a2 KO markedly reversed the function of FSH. Also, FSH upregulated miR-7a by activating the (c-Jun N-terminal kinase) JNK signaling pathway. In addition, Golgi apparatus protein 1 (Glg1) was shown to be the target gene of miR-7a2. These findings indicated that miR-7a2 is essential for ovarian functions with respect to estrogen synthesis through the targeted inhibition of the expression of Glg1 and then promoting Cyp19a1 expression; the physiological process was positively regulated by FSH via the JNK signaling pathway in granulosa cells.     

MicroRNA-29a Manifests Multifaceted Features to Intensify Radiosensitivity,Escalate Apoptosis,and Revoke Cell Migration for Palliating Radioresistance-Enhanced Cervical Cancer Progression

Radioresistance remains a major clinical challenge in cervical cancer therapy and results in tumor relapse and metastasis. Nevertheless, the detailed mechanisms are still largely enigmatic. This study was conducted to elucidate the prospective impacts of microRNA-29a (miR-29a) on the modulation of radioresistance-associated cervical cancer progression. Herein, we established two pairs of parental wild-type (WT) and radioresistant (RR) cervical cancer cells (CaSki and C33A), and we found that constant suppressed miR-29a, but not miR-29b/c, was exhibited in RR-clones that underwent a dose of 6-Gy radiation treatment. Remarkably, radioresistant clones displayed low radiosensitivity, and the reduced apoptosis rate resulted in augmented surviving fractions, measured by the clonogenic survival curve assay and the Annexin V/Propidium Iodide apoptosis assay, respectively. Overexpression of miR-29a effectively intensified the radiosensitivity and triggered the cell apoptosis in RR-clones. In contrast, suppressed miR-29a modestly abridged the radiosensitivity and abolished the cell apoptosis in WT-clones. Hence, ectopically introduced miR-29a into RR-clones notably attenuated the wound-healing rate and cell migration, whereas reduced miR-29a aggravated cell mobilities of WT-clones estimated via the in vitro wound-healing assay and time-lapse recording assay. Notably, we further established the in vivo short-term lung locomotion metastasis model in BALB/c nude mice, and we found that increased lung localization was shown after tail-vein injection of RR-CaSki cells compared to those of WT-CaSki cells. Amplified miR-29a significantly eliminated the radioresistance-enhanced lung locomotion. Our data provide evidence suggesting that miR-29a is a promising microRNA signature in radioresistance of cervical cancer cells and displays multifaceted innovative roles involved in anti-radioresistance, escalated apoptosis, and anti-cell migration/metastasis. Amalgamation of a nucleoid-based strategy (miR-29a) together with conventional radiotherapy may be an innovative and eminent strategy to intensify the radiosensitivity and further protect against the subsequent radioresistance and the potential metastasis in cervical cancer treatment.     

The V-ATPase a3 Subunit: Structure,Function and Therapeutic Potential of an Essential Biomolecule in Osteoclastic Bone Resorption

This review focuses on one of the 16 proteins composing the V-ATPase complex responsible for resorbing bone: the a3 subunit. The rationale for focusing on this biomolecule is that mutations in this one protein account for over 50% of osteopetrosis cases, highlighting its critical role in bone physiology. Despite its essential role in bone remodeling and its involvement in bone diseases, little is known about the way in which this subunit is targeted and regulated within osteoclasts. To this end, this review is broadened to include the three other mammalian paralogues (a1, a2 and a4) and the two yeast orthologs (Vph1p and Stv1p). By examining the literature on all of the paralogues/orthologs of the V-ATPase a subunit, we hope to provide insight into the molecular mechanisms and future research directions specific to a3. This review starts with an overview on bone, highlighting the role of V-ATPases in osteoclastic bone resorption. We then cover V-ATPases in other location/functions, highlighting the roles which the four mammalian a subunit paralogues might play in differential targeting and/or regulation. We review the ways in which the energy of ATP hydrolysis is converted into proton translocation, and go in depth into the diverse role of the a subunit, not only in proton translocation but also in lipid binding, cell signaling and human diseases. Finally, the therapeutic implication of targeting a3 specifically for bone diseases and cancer is discussed, with concluding remarks on future directions.     

Polymorphisms in DNA Repair Genes (APEX1, XPD,XRCC1 and XRCC3) and Risk of Preeclampsia in a Mexican Mestizo Population

Variations in genes involved in DNA repair systems have been proposed as risk factors for the development of preeclampsia (PE). We conducted a case-control study to investigate the association of Human apurinic/apyrimidinic (AP) endonuclease (APEX1) Asp148Glu (rs1130409), Xeroderma Pigmentosum group D (XPD) Lys751Gln (rs13181), X-ray repair cross-complementing group 1 (XRCC) Arg399Gln (rs25487) and X-ray repair cross-complementing group 3 (XRCC3) Thr241Met (rs861539) polymorphisms with PE in a Mexican population. Samples of 202 cases and 350 controls were genotyped using RTPCR. Association analyses based on a χ² test and binary logistic regression were performed to determine the odds ratio (OR) and a 95% confidence interval (95% CI) for each polymorphism. The allelic frequencies of APEX1 Asp148Glu polymorphism showed statistical significant differences between preeclamptic and normal women (p = 0.036). Although neither of the polymorphisms proved to be a risk factor for the disease, the APEX1 Asp148Glu polymorphism showed a tendency of association (OR: 1.74, 95% CI = 0.96–3.14) and a significant trend (p for trend = 0.048). A subgroup analyses revealed differences in the allelic frequencies of APEX1 Asp148Glu polymorphism between women with mild preeclampsia and severe preeclampsia (p = 0.035). In conclusion, our results reveal no association between XPD Lys751Gln, XRCC Arg399Gln and XRCC3 Thr241Met polymorphisms and the risk of PE in a Mexican mestizo population; however, the results in the APEX1 Asp148Glu polymorphism suggest the need for future studies using a larger sample size.     

Improved activity and stability of pseudomonas capaci lipase in a novel biocompatible ionic liquid, 1‐isobutyl‐3‐methylimidazolium hexafluorophosphate

BACKGROUND: Enzymes may exhibit enhanced activity, stability and selectivity in ionic liquids, depending on the properties of the liquid. The physical–chemical properties of ionic liquids, however, may be modified by altering the anion or cation in the ionic liquid. This feature is a key factor for realizing successful reactions. In this work, a new ionic liquid, 1‐isobutyl‐3‐methylimidazolium hexafluorophosphate (abbreviated as [i‐C₄mim][PF₆]), was synthesized and investigated as a novel medium for the transesterification reaction of 2‐phenylethanol with vinyl acetate catalyzed by pseudomonas capaci lipase. As contrasts, the reaction was also carried out in two reference solvents; the isomeric ionic liquid [i‐C₄mim][PF₆], 1‐butyl‐3‐methylimidazolium hexafluorophosphate (abbreviated as [C₄mim][PF₆]), and hexanes. RESULTS: As reaction medium, [i‐C₄mim][PF₆] was best among the three solvents. The initial reaction rate, the equilibrium conversion of 2‐phenylethanol and the half‐lifetime of the lipase in [i‐C₄mim][PF₆] medium were about 1.5, 1.2 and 3‐fold that obtained in [C₄mim][PF₆] medium, respectively. The lipase in [i‐C₄mim][PF₆] medium was recycled 10 times without substantial diminution in activity. CONCLUSION: The ionic liquid [i‐C₄mim][PF₆] has good biocompatibility, and can be used widely as green media in various biocatalysis reactions to improve the activity and stability of enzymes. Besides hydrophobicity and nucleophilicity, the spatial configuration of ionic liquids is also considered a key factor effecting the behaviour of the enzyme in ionic liquids. Copyright © 2008 Society of Chemical Industry     

Odorless,Regioselective Synthesis of Diaryl Sulfides and α‐Thioaryl Carbonyls from Sodium Arylsulfinates via a Metal‐ Free Radical Strategy in Water

Regioselective arylthiolations of aromatic amines, arenols and ketones via C–H bond functionalization have been achieved with I₂ and PPh₃ in an aqueous system, whereby arylsulfenyl radicals are in situ generated from odorless sodium arylsulfinates. The arylsulfenyl radicals can react with free anilines containing electron‐withdrawing groups and complex substrates (estrone and progesterone). Further experiments and quantum chemical calculations were also performed to deduce a mechanism for the formation of arylsulfenyl radicals.

     

TGF-β1 Potentiates the Cytotoxicity of Cadmium by Induction of a Metal Transporter,ZIP8, Mediated by the ALK5-Smad2/3 and ALK5-Smad3-p38 MAPK Signal Pathways in Cultured Vascular Endothelial Cells

Vascular endothelial cells cover the luminal surface of blood vessels in a monolayer and play a role in the regulation of vascular functions, such as the blood coagulation-fibrinolytic system. When the monolayer is severely or repeatedly injured, platelets aggregate at the damaged site and release transforming growth factor (TGF)-β₁ in large quantities from their α-granules. Cadmium is a heavy metal that is toxic to various organs, including the kidneys, bones, liver, and blood vessels. Our previous study showed that the expression level of Zrt/Irt-related protein 8 (ZIP8), a metal transporter that transports cadmium from the extracellular fluid into the cytosol, is a crucial factor in determining the sensitivity of vascular endothelial cells to cadmium cytotoxicity. In the present study, TGF-β₁ was discovered to potentiate cadmium-induced cytotoxicity by increasing the intracellular accumulation of cadmium in cells. Additionally, TGF-β₁ induced the expression of ZIP8 via the activin receptor-like kinase 5-Smad2/3 signaling pathways; Smad3-mediated induction of ZIP8 was associated with or without p38 mitogen-activated protein kinase (MAPK). These results suggest that the cytotoxicity of cadmium to vascular endothelial cells increases when damaged endothelial monolayers that are highly exposed to TGF-β₁ are repaired.