A series of nonsecosteroidal vitamin D receptor agonists for osteoporosis therapy

In an extension of our study on gamma hydroxy carboxylic acid analogs, we explored a series of nonsecosteroidal vitamin D receptor (VDR) agonists in which 1,3-diol of 1,25(OH)₂D₃ had been replaced by aryl acetic acid. These analogs showed very potent activity in vitro compared with 1,25(OH)₂D₃. An X-ray analysis of 8d showed that the inserted phenyl ring well mimicked the folded methylene linker of the gamma hydroxy carboxylic acid moiety but the carboxylic acid of 8d interacted with VDR in a different manner from gamma hydroxy carboxylic acids. Through our in vivo screening in an osteoporosis rat model using immature rats, we identified a potent active vitamin D₃ analog, compound 7e. In mature rats of the same model, compound 7e also showed good PK profiling and excellent ability to prevent bone mineral density loss without severe hypercalcemia. Our nonsecosteroidal VDR agonist 7e (CH5036249) could be a possible new drug candidate for treating osteoporosis in human.     

Brain Training Game Boosts Executive Functions,Working Memory and Processing Speed in the Young Adults: A Randomized Controlled Trial

Background

Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.

Methods

We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).

Results and Discussion

Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.

Conclusions

Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.

Trial Registration

UMIN Clinical Trial Registry 000005618.     

Liposome-encapsulated superoxide dismutase suppresses liposome-mediated augmentation of TNF-alpha production from peripheral blood leucocytes

Liposome-encapsulated hemoglobin (LEH), a candidate for a red cell substitute, has been reported to be cleared from circulation primarily by the phagocytic system and modulate the production of inflammatory cytokines, such as TNF-alpha and IL-6, both in vivo and in vitro. In this study, we investigated the effects of liposome vesicles on the LPS-induced TNF-alpha production using a whole blood culture system. We also studied the effects of superoxide dismutase (SOD) encapsulated in liposome on the cytokine production. The pre-treatment of whole blood with liposome vesicles potentiated the LPS-induced TNF-alpha production. The encapsulation of SOD in the liposome vesicles suppressed the liposome-mediated augmentation of TNF-alpha production in a dose-dependent manner. These results suggest that encapsulation of SOD in LEH decreases the production of inflammatory cytokines from the phagocytic system which may be caused or augmented by LEH infusion in vivo.     

Alteration of mosaic methylation of the repeat unit of the human ribosomal RNA genes in lung cancer

We have investigated the methylation status of the repeat unit of the human ribosomal RNA genes in lung cancer. Using a Southern blot analysis approach we have determined that the non-transcribed region of these genes was generally heavily methylated, while the transcribed region was not methylated in either tumor or normal DNA. Our study also revealed that, in one tumor, the boundary of mosaic methylation of the repeat unit was not distinct. In the same tumor, both the non-transcribed ribosomal spacer region and the L1 interspersed repeat sequences became partially demethylated. In tumor cells, the methylation status of DNA can be altered, but the methylation of subtelomeric repeats was found to be maintained. These results suggest that the mosaic methylation of the repeat unit is not necessarily maintained in tumor DNA, while subtelomeric repeats escape tumor-specific wave of demethylation.     

Functional significance of the conserved residues for the 23-residue module among MTH1 and MutT family proteins

Human MTH1 and Escherichia coli MutT proteins hydrolyze 7, 8-dihydro-8-oxo-dGTP (8-oxo-dGTP) to monophosphate, thus avoiding the incorporation of 8-oxo-7,8-dihydroguanine into nascent DNA. Although only 30 amino acid residues (23%) are identical between MTH1 and MutT, there is a highly conserved region consisting of 23 residues (MTH1, Gly(36)-Gly(58)) with 14 identical residues. A chimeric protein MTH1-Ec, in which the 23-residue sequence of MTH1 was replaced with that of MutT, retains its capability to hydrolyze 8-oxo-dGTP, thereby indicating that the 23-residue sequences of MTH1 and MutT are functionally and structurally equivalent and constitute functional modules. By saturation mutagenesis of the module in MTH1, 14 of the 23 residues proved to be essential to exert 8-oxo-dGTPase activity. For the other 9 residues (40, 42, 44, 46, 47, 49, 50, 54, and 58), positive mutants were obtained, and Arg(50) can be replaced with hydrophobic residues (Val, Leu, or Ile), with a greater stability and higher specific activity of the enzyme. Indispensabilities of Val(39), Ile(45), and Leu(53) indicate that an amphipathic property of alpha-helix I consisting of 14 residues of the module (Thr(44)-Gly(58)) is essential to maintain the stable catalytic surface for 8-oxo-dGTPase.     

Bleomycin stimulates lung fibroblasts to release neutrophil and monocyte chemotactic activity

We determined whether human lung fibroblasts might release chemotactic activity for neutrophils (NCA) and monocytes (MCA) in response to bleomycin. The human lung fibroblasts supernatant fluids were evaluated for chemotactic activity by a blind well chamber technique. Human lung fibroblasts released NCA and MCA in a dose- and time-dependent manner in response to bleomycin. Checkerboard analysis of supernatant fluids revealed that both NCA and MCA were chemotactic. Partial characterization revealed that NCA was partly heat labile, trypsin sensitive, and predominantly ethyl acetate extractable. In contrast, MCA was partly trypsin sensitive and ethyl acetate extractable. The release of chemotactic activity was inhibited by lipoxygenase inhibitors and cycloheximide. Molecular sieve column chromatography revealed that both NCA and MCA had multiple chemotactic peaks. NCA was inhibited by leukotriene B4 receptor antagonist and anti-IL-8 and G-CSF Abs. MCA was attenuated by leukotriene B4 receptor antagonist, and monocyte chemoattractant protein-1, GM-CSF, and TGF-beta Abs. Leukotriene B4 receptor antagonist and these Abs inhibited the corresponding m.w. chemotactic activity separated by column chromatography. The concentrations of IL-8, G-CSF, monocyte chemoattractant protein-1, GM-CSF, and TGF-beta in the supernatant fluids significantly increased in response to bleomycin. These data suggest that lung fibroblasts may modulate inflammatory cell recruitment into the lung by releasing NCA and MCA in response to bleomycin.     

The composition of newly synthesized proteins in the endoplasmic reticulum determines the transport pathways of soybean seed storage proteins

Glycinin (11S) and beta-conglycinin (7S) are major storage proteins in soybean (Glycine max L.) seeds and accumulate in the protein storage vacuole (PSV). These proteins are synthesized in the endoplasmic reticulum (ER) and transported to the PSV by vesicles. Electron microscopic analysis of developing soybean cotyledons of the wild type and mutants with storage protein composition different from that of the wild type showed that there are two transport pathways: one is via the Golgi and the other bypasses it. Golgi-derived vesicles were observed in all lines used in this study and formed smooth dense bodies with a diameter of 0.5 to several micrometers. ER-derived protein bodies (PBs) with a diameter of 0.3-0.5 microm were observed at high frequency in the mutants containing higher amount of 11S group I subunit than the wild type, whereas they were hardly observed in the mutants lacking 11S group I subunit. These indicate that pro11S group I may affect the formation of PBs. Thus, the composition of newly synthesized proteins in the ER is important in the selection of the transport pathways.