Expression patterns of hedgehog, wingless, and decapentaplegic during gut formation of Gryllus bimaculatus (cricket).

We observed expression patterns of hedgehog (hh), wingless (wg), and decapentaplegic (dpp) during gut development of Gryllus bimaculatus (the cricket), a typical hemimetabolous insect, and compared with those observed in Drosophila, a typical holometabolous insect. Gryllus hh(Gbhh) and Gbwg are expressed in both foregut and hindgut, while Gbdpp is expressed only in the hindgut: at the boundaries between the small and large intestine, and between the large intestine and rectum. Although the expression patterns of Gbhh and Gbwg are essentially comparable to those observed in Drosophila, the expression pattern of Gbdpp differs from those of the Drosophila dpp.     

Protective effects of mangafodipir against chemotherapy-induced ovarian damage in mice

Background

Given the seriousness of chemotherapy-induced ovarian injury in female cancer patients, the preservation of fertility, including through the use of cryopreservation technology and pharmaceuticals, requires investigation. Previous studies have shown that damage to the ovaries is related to oxidative stress caused by anticancer drugs. Therefore, superoxide dismutase (SOD) may represent a key factor in the pharmacological protection of the ovaries. The aim of our study was to identify the effects of mangafodipir, a manganese chelate and SOD-mimetic, on suppression of apoptosis in granulosa cells and primordial follicle activation induced by anticancer drugs.

Methods

Cell viability assays using methyltrichlorosilane solutions and immunoblotting for cleaved caspase-3 were performed in in vitro experiments with the simultaneous addition of mangafodipir to human non-luteinized granulosa cell line (HGrC) cultures treated with hydrogen peroxide (H₂O₂), cisplatin, or paclitaxel. Count and morphological analyses of follicles at each developing stage in the ovaries and immunohistochemistry for cleaved caspase-3, Ki67 and 4-hydroxynonenal, a marker for oxidative stress, were also performed using mangafodipir-injected 6-week-old female ICR mice treated with cisplatin or paclitaxel. Further, mangafodipir was injected into 6-week-old female BALB/c mice inoculated with ES-2 to analyze whether mangafodipir inhibits the anti-tumor effects of cisplatin or paclitaxel treatment.

Results

Mangafodipir attenuated apoptosis induced by H₂O₂ and anticancer drugs in vitro. Mangafodipir also decreased the expression of 4-hydroxynonenal and reduced cisplatin- and paclitaxel-induced apoptosis in granulosa cells in vivo. In addition, mangafodipir inhibited the loss of primordial follicles. Tumor xenograft studies in mice showed that mangafodipir did not affect anticancer drug antitumor effects.

Conclusions

Oxidative stress might be one of the mechanisms of cisplatin- and paclitaxel-induced the loss of primordial follicles. Mangafodipir can reduce cisplatin- and paclitaxel-induced apoptosis in granulosa cells and primordial follicle activation partially via its SOD activity. At the same time, mangafodipir might have other potential mechanisms to inhibit the activation of primordial follicles. Further, mangafodipir attenuated the ovarian damage caused by cisplatin and paclitaxel without affecting their antitumor activities. Mangafodipir, therefore, though its efficacy might be limited, may be a new option for the preservation of fertility during anticancer treatment.

     

Selective synthesis of 7-O-substituted luteolin derivatives and their melanonenesis and proliferation inhibitory activity in B16 melanoma cells

In our previous study, the isolation of ugonin J, K, and L, which are luteolin derivatives, from the roots of Helminthostachys zeylanica and their identification as potent melanogenesis inhibitors, was described. The structure activity relationship (SAR) investigation in that study revealed that the catechol moiety in the B-ring of the flavone skeleton of ugonin K was important for its melanogenesis inhibitory activity, and the presence of the low polarity substituents at the C-7 position enhanced this activity. In order to further investigate the SAR of the C-7-substituent in the luteolin derivatives, different groups were selectively introduced at the C-7 position of luteolin after borax protection of the catechol hydroxyl group and the C-5 hydroxyl group. NMR and MS analysis of the borax protected derivatives revealed that the borax protects not only hydroxyl groups of catechol on the B ring but also the 5-hydroxyl group on the A ring. Eight luteolin derivatives were synthesized and evaluated for melanogenesis inhibitory effect in B16 melanoma cells. Two bulky groups and six alkoxyl groups were introduced at the C-7 position. The resulting luteolin derivatives showed improved melanogenesis and cell proliferation inhibitory activities. From among these derivatives, 7-O-hexylluteolin (7) showed the highest activity and inhibited the melanogenesis to 14% at 6.25?μM. The present study also revealed that the length of the carbon chain rather than the bulky substituent was more important for the melanogenesis inhibitory activity.     

Theoretical calculation of triazolam hydroxylation and endogenous steroid inhibition in the active site of CYP3A4

CYP3A4 has unusual kinetic characteristics because it has a large active site. CYP3A4 produced more 4-hydroxytriazolam than alpha-hydroxytriazolam at concentrations of more than 60 muM triazolam, and different steroids had different inhibitory effects on the system. To clarify these interesting observations, the interactions between substrate and substrate/steroid were investigated by theoretical calculations. When two triazolam molecules were docked into the active site, the distance between the O-atom and the 4-hydroxylated site was less than the distance to the alpha-hydroxylated site because of interaction between the two triazolam molecules. Estradiol inhibited both alpha- and 4-hydroxytriazolam formation by 50%. Dehydroepiandrosterone (DHEA) inhibited alpha-hydroxylation more than 4-hydroxytriazolam formation, whereas aldosterone had no effect. When one triazolam molecule and one steroid molecule were simultaneously docked, estradiol increased the distance between the O-atom and the two hydroxylated sites, DHEA only increased the distance between the O-atom and alpha-hydroxylated site, and aldosterone did not change the distances. The relevant angles of Fe-O-C in the hydroxylated site of triazolam also widened, together with increased distance. These findings indicate that formation of a substrate and substrate/effector complex in the active site may be a factor for determining the enzyme kinetic parameters of CYP3A4.     

Bio-photosensor: Cyanobacterial photosystem I coupled with transistor via molecular wire

We report on the first successful output of electrons directly from photosystem I (PSI) of thermophilic cyanobacteria to the gate of a field-effect transistor (FET) by bypassing electron flow via a newly designed molecular wire, i.e., artificial vitamin K(1), and a gold nanoparticle; in short, this newly manufactured photosensor employs a bio-functional unit as the core of the device. Photo-electrons generated by the irradiation of molecular complexes composed of reconstituted PSI on the gate were found to control the FET. This PSI-bio-photosensor can be used to interpret gradation in images. This PSI-FET system is moreover sufficiently stable for use exceeding a period of 1 year.     

Bio-photosensor: Cyanobacterial photosystem I coupled with transistor via molecular wire

We report on the first successful output of electrons directly from photosystem I (PSI) of thermophilic cyanobacteria to the gate of a field-effect transistor (FET) by bypassing electron flow via a newly designed molecular wire, i.e., artificial vitamin K₁, and a gold nanoparticle; in short, this newly manufactured photosensor employs a bio-functional unit as the core of the device. Photo-electrons generated by the irradiation of molecular complexes composed of reconstituted PSI on the gate were found to control the FET. This PSI-bio-photosensor can be used to interpret gradation in images. This PSI-FET system is moreover sufficiently stable for use exceeding a period of 1 year.     

Functional lysophosphatidic acid receptors expressed in Oryzias latipes

Lysophosphatidic acid (LPA) signaling is known to play biological and pathophysiological roles in many types of animals. Medaka (Oryzias latipes) is an experimental fish that can be easily maintained, propagated, and analyzed, and whose genome has been completely sequenced. However, there is limited information available regarding medaka LPA receptors. Here, using information from the medaka genome database, we examine the genomic structures, expression, and functions of six LPA receptor genes, Lpar1–Lpar6. Our analyses reveal that the genomic structures of Lpar1 and Lpar4 are different from those deduced from the database. Functional analyses using a heterologous expression system demonstrate that all medaka LPA receptors except for LPA_5b respond to LPA treatment with cytoskeletal changes. These findings provide useful information on the structure and function of medaka LPA receptor genes, and identify medaka as a useful experimental model for exploration of the biological significance of LPA signaling.     

Three-dimensional ultrastructure of feeding tubes and interconnected endoplasmic reticulum in root-knot nematode-induced giant cells in rose balsam

We investigated the three-dimensional ultrastructure of feeding tubes and the surrounding region in giant cells induced in rose balsam (Impatiens balsamina L.) roots by the root-knot nematode Meloidogyne incognita, using osmium maceration coupled with field emission scanning electron microscopy (FE-SEM). In the roots of 35-day-old galled rose balsam plants, adult nematodes induced the formation of giant cells containing feeding tubes and numerous organelles, including tubular endoplasmic reticulum (ER), cisternal ER, and mitochondria. The feeding tubes were surrounded by fine tubular structures (20–50 nm in diameter), which were in turn surrounded by tubular ER (approximately 120 nm in diameter). The termini of the fine tubular structures appeared to be connected to the surface of the feeding tubes, suggesting that the fine tubular structures were continuous with narrow channels in the feeding tubes. The tubular ER arose from cisternal ER. Large bundles of tubular ER were present near the feeding tube, in the centers of the giant cells, and in the peripheral regions of the giant cells, such as cell wall ingrowths, while smaller bundles of tubular ER formed networks in the giant cells. These observations suggest that tubular ER functions as vascular bundles in giant cells, facilitating the transport of nutrients. We identified capsule-shaped structures (30 μm in diameter) in the giant cells that consisted of smooth, repeatedly branched ER tubules wrapped in several layers of cisternal ER. We propose that lipids and steroids are synthesized at the smooth branched ER and stored in these capsules until needed by the nematode.