Identification of a small RhoA GTPase inhibitor effective in fission yeast and human cells.

The Rho GTPase family proteins are key regulators of cytoskeletal dynamics. Deregulated activity of Rho GTPases is associated with cancers and neurodegenerative diseases, and their potential as drug targets has long been recognized. Using an economically effective drug screening workflow in fission yeast and human cells, we have identified a Rho GTPase inhibitor, O1.

Identification of novel microtubule inhibitors effective in fission yeast and human cells and their effects on breast cancer cell lines.

Microtubules are critical for a variety of cellular processes such as chromosome segregation, intracellular transport and cell shape. Drugs against microtubules have been widely used in cancer chemotherapies, though the acquisition of drug resistance has been a significant issue for their use. To identify novel small molecules that inhibit microtubule organization, we conducted sequential phenotypic screening of fission yeast and human cells.

Characterization of Mutants That Exhibit Strong Positive Phototaxis.

The most motile phototrophic organisms exhibit photo-induced behavioral responses (photobehavior) to inhabit better light conditions for photosynthesis. The unicellular green alga is an excellent model organism to study photobehavior. Several years ago, we found that cells reverse their phototactic signs (i.

Reoxygenation with 100% Oxygen Following Hypoxia in Mice Causes Apoptosis.

After hypoxia, reoxygenation with air is the consensus treatment for full-term neonates; however, the effect of hyperoxic reoxygenation of adults is unknown. The present study was designed to investigate the effects of reoxygenation with 100% oxygen after hypoxia on inflammation and apoptosis in mice. Eight-week-old mice were either subjected to hypoxia in 8% oxygen for 30 min or air served as controls.

Effects of sevoflurane exposure during late pregnancy on brain development of offspring mice.

Background: Exposure to some anesthetic agents during the fetal period has been shown to induce neurodegeneration or learning deficits in animal models. Sevoflurane is one of the most prevalent general anesthetics; however, the influence of sevoflurane at a clinically relevant concentration on the developing fetal brain remains unknown.

Objective: We investigated whether a single sevoflurane exposure during the fetal period would affect neuronal development and learning/memory ability in mice.

T-5224, a selective inhibitor of c-Fos/activator protein-1, improves survival by inhibiting serum high mobility group box-1 in lethal lipopolysaccharide-induced acute kidney injury model.

Background: Sepsis is a potentially fatal syndrome mediated by an early [e.g., tumor necrosis factor-alpha (TNF-α)] and late [high mobility group box-1 (HMGB-1)] proinflammatory cytokine response to infection.

CDK7 regulates the mitochondrial localization of a tail-anchored proapoptotic protein, Hid.

The mitochondrial outer membrane is a major site of apoptosis regulation across phyla. Human and C. elegans Bcl-2 family proteins and Drosophila Hid require the C-terminal tail-anchored (TA) sequence in order to insert into the mitochondrial membrane, but it remains unclear whether cytosolic proteins actively regulate the mitochondrial localization of these proteins.

D-ribose ameliorates cisplatin-induced nephrotoxicity by inhibiting renal inflammation in mice.

Cisplatin is one of the most potent chemotherapeutic anticancer drugs, but it can produce side effects such as nephrotoxicity. Inflammatory cytokines, chemokines and adhesion molecules have important roles in the pathogenesis of cisplatin-induced nephrotoxicity. D-Ribose is a naturally occurring five-carbon monosaccharide that is found in all living cells, and has anti-inflammatory effects in renal ischemia/reperfusion injury.

Curcumin ameliorates cisplatin-induced nephrotoxicity by inhibiting renal inflammation in mice.

Inflammatory mechanisms may play an important role in the pathogenesis of cisplatin-induced nephrotoxicity. Curcumin is an orange-yellow polyphenol present in curry spice and has anti-inflammatory and antioxidant effects. The purpose of this study was to determine the protective effects of curcumin on cisplatin-induced nephrotoxicity.

The effects of a selective inhibitor of c-Fos/activator protein-1 on endotoxin-induced acute kidney injury in mice.

Background: Sepsis has been identified as the most common cause of acute kidney injury (AKI) in intensive care units. Lipopolysaccharide (LPS) induces the production of several proinflammatory cytokines including tumor necrosis factor (TNF)-alpha, a major pathogenetic factor in septic AKI. c-Fos/activator protein (AP)-1 controls the expression of these cytokines by binding directly to AP-1 motifs in the cytokine promoter regions.

Erythropoietin attenuates isoflurane-induced neurodegeneration and learning deficits in the developing mouse brain.

Objectives: To examine whether recombinant erythropoietin (rEPO) attenuates neurodegeneration and the learning disability induced by isoflurane with the postnatal day 7 (P7) mice.

Background: Some of general anesthetic agents induce neurodegeneration in developing brain. Several drugs, but not rEPO, were reported as candidates for the prevention of or treatment for neurodegeneration.

[Case of transient paralysis and paresthesia after epidural blood patch].

A 47-year-old woman with postdural puncture headache suffered from transient paralysis and paresthesia immediately after the epidural blood patch. After one and a half hour, these symptoms disappeared spontaneously. We suspect that the spinal cord or spinal nerve root was transiently pressed by the viscous blood mass, because blood sampling maneuver took a few minutes.

The tumor suppressor gene H-Rev107 functions as a novel Ca2+-independent cytosolic phospholipase A1/2 of the thiol hydrolase type.

H-Rev107 is a protein that was previously cloned as a negative regulator of proto-oncogene Ras and classified as a class II tumor suppressor. Its structural similarity to lecithin retinol acyltransferase and Ca2+-independent phosphatidylethanolamine (PE) N-acyltransferase led us to analyze H-Rev107 as an enzyme involved in phospholipid metabolism. Here, we show that recombinant H-Rev107s from rat, human, and mouse possess phospholipase (PL) A1 or A2 activity toward phosphatidylcholine (PC).

Biosynthetic pathways of the endocannabinoid anandamide.

Anandamide (=N-arachidonoylethanolamine) is the first discovered endocannabinoid, and belongs to the class of bioactive, long-chain N-acylethanolamines (NAEs). In animal tissues, anandamide is principally formed together with other NAEs from glycerophospholipid by two successive enzymatic reactions: 1) N-acylation of phosphatidylethanolamine to generate N-acylphosphatidylethanolamine (NAPE) by Ca2+-dependent N-acyltransferase; 2) release of NAE from NAPE by a phosphodiesterase of the phospholipase D type (NAPE-PLD). Although these anandamide-synthesizing enzymes were poorly understood until recently, our cDNA cloning of NAPE-PLD in 2004 enabled molecular-biological approaches to the enzymes.

Discovery and characterization of a Ca2+-independent phosphatidylethanolamine N-acyltransferase generating the anandamide precursor and its congeners.

N-Acylphosphatidylethanolamines (NAPEs) are precursors of bioactive N-acylethanolamines, including the endocannabinoid anandamide. In animal tissues, NAPE is formed by transfer of a fatty acyl chain at the sn-1 position of glycerophospholipids to the amino group of phosphatidylethanolamine (PE), and this reaction is believed to be the principal rate-limiting step in N-acylethanolamine synthesis. However, the Ca2+-dependent, membrane-associated N-acyltransferase (NAT) responsible for this reaction has not yet been cloned.

Functional analysis of the purified anandamide-generating phospholipase D as a member of the metallo-beta-lactamase family.

In animal tissues, bioactive N-acylethanolamines including the endocannabinoid anandamide are formed from their corresponding N-acylphosphatidylethanolamines (NAPEs) by the catalysis of a specific phospholipase D (NAPE-PLD) that belongs to the metallo-beta-lactamase family. Despite its potential physiological importance, NAPE-PLD has not yet been characterized with a purified enzyme preparation. In the present study we expressed a recombinant NAPE-PLD in Escherichia coli and highly purified it.

Regional distribution and age-dependent expression of N-acylphosphatidylethanolamine-hydrolyzing phospholipase D in rat brain.

The endocannabinoid anandamide (N-arachidonoylethanolamine) and other bioactive long-chain N-acylethanolamines are thought to be formed from their corresponding N-acylphosphatidylethanolamines by a specific phospholipase D (NAPE-PLD) in the brain as well as other tissues. However, regional distribution of NAPE-PLD in the brain has not been examined. In the present study, we investigated the expression levels of NAPE-PLD in nine different regions of rat brain by enzyme assay, western blotting and real-time PCR.

N-acylphosphatidylethanolamine-hydrolyzing phospholipase D: a novel enzyme of the beta-lactamase fold family releasing anandamide and other N-acylethanolamines.

N-acylethanolamines (NAEs) are a lipid class present in brain and other animal tissues and contains anandamide (an endocannabinoid) and other bioactive substances. NAEs are formed from N-acylphosphatidylethanolamines (NAPEs) by a phospholipase D (PLD)-type enzyme abbreviated to NAPE-PLD. Although this enzyme has been recognized for more than 20 years, its molecular cloning has only recently been achieved by us.

Mammalian cells stably overexpressing N-acylphosphatidylethanolamine-hydrolysing phospholipase D exhibit significantly decreased levels of N-acylphosphatidylethanolamines.

In animal tissues, NAEs (N-acylethanolamines), including N-arachidonoylethanolamine (anandamide), are primarily formed from their corresponding NAPEs (N-acylphosphatidylethanolamines) by a phosphodiesterase of the PLD (phospholipase D) type (NAPE-PLD). Recently, we cloned cDNAs of NAPE-PLD from mouse, rat and human [Okamoto, Morishita, Tsuboi, Tonai and Ueda (2004) J. Biol.

Molecular characterization of a phospholipase D generating anandamide and its congeners.

Anandamide (N-arachidonoylethanolamine) is known to be an endogenous ligand of cannabinoid and vanilloid receptors. Its congeners (collectively referred to as N-acylethanolamines) also show a variety of biological activities. These compounds are principally formed from their corresponding N-acyl-phosphatidylethanolamines by a phosphodiesterase of the phospholipase D-type in animal tissues.

Involvement of RAD9-dependent damage checkpoint control in arrest of cell cycle, induction of cell death, and chromosome instability caused by defects in origin recognition complex in Saccharomyces cerevisiae.

Perturbation of origin firing in chromosome replication is a possible cause of spontaneous chromosome instability in multireplicon organisms. Here, we show that chromosomal abnormalities, including aneuploidy and chromosome rearrangement, were significantly increased in yeast diploid cells with defects in the origin recognition complex. The cell cycle of orc1-4/orc1-4 temperature-sensitive mutant was arrested at the G2/M boundary, after several rounds of cell division at the restrictive temperature.