Zerumbone Exhibits Anti-Inflammatory Functions via HSF1

Zerumbone is a sesquiterpene present in Zinger zerumbet. Many studies have demonstrated its marked anti-inflammatory and anti-carcinogenesis activities. Recently, we showed that zerumbone binds to numerous proteins with scant selectivity and induces the expression of heat shock proteins (HSPs) in hepatocytes. To dampen proteo-toxic stress, organisms have a stress-responsive molecular machinery, known as heat shock response. Heat shock factor 1 (HSF1) plays a key role in this protein quality control system by promoting activation of HSPs. In this study, we investigated whether zerumbone-induced HSF1 activation contributes to its anti-inflammatory functions in stimulated macrophages. Our findings showed that zerumbone increased cellular protein aggregates and promoted nuclear translocation of HSF1 for HSP expression. Interestingly, HSF1 down-regulation attenuated the suppressive effects of zerumbone on mRNA and protein expressions of pro-inflammatory genes, including inducible nitric oxide synthase and interlukin-1β. These results suggest that proteo-stress induced by zerumbone activates HSF1 for exhibiting its anti-inflammatory functions

Three-dimensional imaging of crack growth in L chondrites after high-velocity impact experiments

Small asteroids such as Itokawa are covered with an unconsolidated regolith layer of centimeter-sized or smaller particles. There are two plausible formation mechanisms for regolith layers on a sub-kilometer-sized asteroid: (i) fragments produced by thermal fatigue by day-night temperature cycles on the asteroid surface and (ii) impact fragment. Previous studies suggest that thermal fatigue induces crack growth along the boundary surface of the mineral grain while impact phenomena may induce crack growth regardless of the boundary surface of the mineral grain. Therefore, it is possible that the crack growth within a mineral grain (and/or a chondrule) differs depending on the crack formation mechanism, be it thermal fatigue or an impact. In order to investigate how mineral grains and chondrules are affected by impact-induced crack growth, we fired spherical alumina projectiles (diameter ~1 mm) into 9 mm side length cubic targets of L chondrites at a nominal impact velocity of 2.0 km/s. Before and after the six successful impact experiments, the cracks within mineral grains and chondrules in the respective targets are examined using X-ray microtomography at a resolution with the voxel size of 9.0 μm. The results show that most cracks within chondrules and troilite (FeS) grow regardless of the boundary surfaces of the grains while most cracks within ductile Fe-Ni metal grow along the boundary surfaces of the grains. This may indicate that crack growth is largely affected by the strength of mineral grains (and/or chondrules). From the experimental results and the fact that the shapes of polymineralic and monomineralic particles from Itokawa are similar, we conclude that the Itokawa particles have not been produced by thermal fatigue but instead are likely to be impact fragments, as described in previous papers (Tsuchiyama et al., 2011, 2014; Michikami et al., 2018)

Expression and Role of IL-1β Signaling in Chondrocytes Associated with Retinoid Signaling during Fracture Healing

The process of fracture healing consists of an inflammatory reaction and cartilage and bone tissue reconstruction. The inflammatory cytokine interleukin-1β (IL-1β) signal is an important major factor in fracture healing, whereas its relevance to retinoid receptor (an RAR inverse agonist, which promotes endochondral bone formation) remains unclear. Herein, we investigated the expressions of IL-1β and retinoic acid receptor gamma (RARγ) in a rat fracture model and the effects of IL-1β in the presence of one of several RAR inverse agonists on chondrocytes. An immunohistochemical analysis revealed that IL-1β and RARγ were expressed in chondrocytes at the fracture site in the rat ribs on day 7 post-fracture. In chondrogenic ATDC5 cells, IL-1β decreases the levels of aggrecan and type II collagen but significantly increased the metalloproteinase-13 (Mmp13) mRNA by real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis. An RAR inverse agonist (AGN194310) inhibited IL-1β-stimulated Mmp13 and Ccn2 mRNA in a dose-dependent manner. Phosphorylated extracellular signal regulated-kinases (pERK1/2) and p-p38 mitogen-activated protein kinase (MAPK) were increased time-dependently by IL-1β treatment, and the IL-1β-induced p-p38 MAPK was inhibited by AGN194310. Experimental p38 inhibition led to a drop in the IL-1β-stimulated expressions of Mmp13 and Ccn2 mRNA. MMP13, CCN2, and p-p38 MAPK were expressed in hypertrophic chondrocytes near the invaded vascular endothelial cells. As a whole, these results point to role of the IL-1β via p38 MAPK as important signaling in the regulation of the endochondral bone formation in fracture healing, and to the actions of RAR inverse agonists as potentially relevant modulators of this process

Single Nucleotide Polymorphisms of the IZUMO Gene in Male Infertile Patients

IZUMOは精子頭部の膜表面に局在し、マウスの精子と卵の受精に必須なタンパク質である。日本人におけるIZUMO遺伝子の多型と精子形成の異常の関係を解析するために、我々は妊孕性の確認されたボランティアの男性１７２人と男性不妊症患者８９２人のゲノムDNAを用いてIZUMO遺伝子の多型と変異の検索を行った。ABI‐PRISM 3730xl Genetic Analyzer and SeqScape software （Applied Biosystems社）を用い解析を行った結果、妊孕性の確認されたボランティアの男性では検出されない一塩基置換を男性不妊症患者に見出した。初回の探索において、男性不妊症患者に４つの一塩基多型（４１７T>G（Cys１３９Trp），５８９A>T（Ser１９７Cys），９３９T>A（Phe３１３Leu），９４４G>A（Arg３１５Gln））が有意に検出された。これらの一塩基置換は、別のプライマーセットを用いた塩基配列解析では検出することができなかったが、一塩基多型と男性不妊症の関係の解析において重要な標的候補と考えられる。IZUMO is a surface protein on sperm and essential for egg fusion in mice. To investigate the possible association between variations in the IZUMO gene and impaired spermatogenesis in Japanese males, we screened for mutations in the human IZUMO gene using DNA from 892 sterile male patients and 172 proven-fertile male volunteers. Single Nucleotide Polymorphisms (SNPs) were identified in the heterozygous state in the infertile patients, and neither variant was identified in fertile subjects using an ABI-PRISM 3730xl Genetic Analyzer and SeqScape software (Applied Biosystems). Four single nucleotide polymorphisms (SNPs), 417 T>G (Cys 139 Trp), 589 A>T (Ser 197 Cys), 939 T>A (Phe 313 Leu), and 944 G>A (Arg 315 Gln), were found significantly more often in infertile subjects than in fertile controls in the first screening. Otherwise, the four SNPs were not detected by direct sequencing using the other primers. These results show that four SNPs exist as an analytical target of SNPs that associated with the male infertility n the IZUMO gene

Paraganglioma that caused sinus arrest

Paragangliomas are neural-crest-derived nonepithelial neuroendocrine tumors distributed along the parasympathetic and sympathetic nerves. To our knowledge, no studies were reported regarding sinus arrest on day 4 after paraganglioma resection. A 66-year-old female patient with a history of pulmonary vein isolation visited our department for sigmoid colon cancer treatment. Enhanced computed tomography revealed an enhanced small nodule-like lymph node near the root of the inferior mesenteric artery. The patient underwent laparoscopic colectomy with regional lymph node dissection. Postoperatively, paroxysmal atrial fibrillation attacks developed, and the patient resumed oral medication. Additionally, sinus arrest after tachycardia developed. Changing the oral medication could maintain her circulatory dynamics. Pathological examination revealed that differentiated tubular adenocarcinoma infiltrated the submucosa. Immunohistochemically, the excised nodule as a lymph node was considered a functional paraganglioma. Our case indicates that paraganglioma resection and oral medication resumption may contribute to sinus arrest. When arrhythmias affecting the circulation occur perioperatively, the presence of a catecholamine-producing tumor should be considered in addition to cardiac disease

Mutant PKC gamma in Spinocerebellar Ataxia Type 14 Disrupts Synapse Elimination and Long-Term Depression in Purkinje Cells In Vivo

Cerebellar Purkinje cells (PCs) express a large amount of the gamma isoform of protein kinase C (PKC gamma) and a modest level of PKC alpha. The PKC gamma is involved in the pruning of climbing fiber (CF) synapses from developing PCs, and PKC alpha plays a critical role in long-term depression (LTD) at parallel fiber (PF)-PC synapses. Moreover, the PKC signaling in PCs negatively modulates the nonselective transient receptor potential cation channel type 3 (TRPC3), the opening of which elicits slow EPSCs at PF-PC synapses. Autosomal dominant spinocerebellar ataxia type 14 (SCA14) is caused by mutations in PKC gamma. To clarify the pathology of this disorder, mutant (S119P) PKC gamma tagged with GFP was lentivirally expressed in developing and mature mouse PCs in vivo, and the effects were assessed 3 weeks after the injection. Mutant PKC gamma-GFP aggregated in PCs without signs of degeneration. Electrophysiology results showed impaired pruning of CF synapses from developing PCs, failure of LTD expression, and increases in slow EPSC amplitude. We also found that mutant PKC gamma colocalized with wild-type PKC gamma, which suggests that mutant PKC gamma acts in a dominant-negative manner on wild-type PKC gamma. In contrast, PKC alpha did not colocalize with mutant PKC gamma. The membrane residence time of PKC alpha after depolarization-induced translocation, however, was significantly decreased when it was present with the mutant PKC gamma construct. These results suggest that mutant PKC gamma in PCs of SCA14 patients could differentially impair the membrane translocation kinetics of wild-type gamma and alpha PKCs, which would disrupt synapse pruning, synaptic plasticity, and synaptic transmission