Effects of lotus root (the edible rhizome of Nelumbo nucifera) on the deveolopment of non-alcoholic fatty liver disease in obese diabetic db/db mice

Non-alcoholic fatty liver disease (NAFLD) is emerging as the most common liver disease in industrialized countries. The discovery of food components that would ameliorate NAFLD is therefore of interest. Lotus root, the edible rhizome of Nelumbo nucifera, contains a high level of polyphenolic compounds, and several health-promoting properties of lotus root have been reported. The present study examines whether dietary lotus root powder can protect db/db mice from hepatic injury. After 3 weeks of feeding, the hepatomegaly, hepatic triglyceride accumulation, and elevated hepatic injury markers in the serum were markedly alleviated in the Lotus diet-fed db/db mice relative to the control mice. These effects were partly attributable to suppression of the lipogenic enzyme activities and mRNA expression by the Lotus diet. The serum levels of adiponectin, which has been reported to have a protective effect against NAFLD, were significantly higher in the Lotus group than in the Control group of the db/db mice. Moreover, the hepatic expression of such inflammatory genes as tumor necrosis factor-alpha and monocyte chemoattractant protein-1 were markedly suppressed by the Lotus diet. We speculate that the development and progression of NAFLD were prevented by suppressing the expression of lipogenic and inflammatory genes as a result of the higher serum adioponectin level in the Lotus diet-fed db/db mice.     

Protein recognition of hetero-/homoleptic ruthenium(II) tris(bipyridine)s for α-chymotrypsin and cytochrome c

We examined the relationship between the structures of hetero-/homoleptic ruthenium(II) tris(bipyridine) metal complexes (Ru(II)(bpy)(3)) and their binding properties for α-chymotrypsin (ChT) and cytochrome c (cyt c). Heteroleptic compound 1a binds to both ChT and cyt c in 1:1 ratio, whereas homoleptic 2 forms 1:2 protein complex with ChT but 1:1 complex with cyt c. These results suggest that the structure of the recognition cavity in Ru(II)(bpy)(3) can be designed for shape complementarity to the targeted proteins. In addition, Ru(II)(bpy)(3) complexes were found to be potent inhibitors of cyt c reduction and to permeate A549 cells.     

Characterization of the rice blast resistance gene Pik cloned from Kanto51

To study similar, but distinct, plant disease resistance (R) specificities exhibited by allelic genes at the rice blast resistance locus Pik/Pikm, we cloned the Pik gene from rice cultivar Kanto51 and compared its molecular features with those of Pikm and of another Pik gene cloned from cv. Kusabue. Like Pikm, Pik is composed of two adjacent NBS-LRR (nucleotide-binding site, leucine-rich repeat) genes: the first gene, Pik1-KA, and the second gene, Pik2-KA. Pik from Kanto51 and Pik from Kusabue were not identical; although the predicted protein sequences of the second genes were identical, the sequences differed by three amino acids within the NBS domain of the first genes. The Pik proteins from Kanto51 and Kusabue differed from Pikm in eight and seven amino acids, respectively. Most of these substituted amino acids were within the coiled-coil (CC) and NBS domains encoded by the first gene. Of these substitutions, all within the CC domain were conserved between the two Pik proteins, whereas all within the NBS domain differed between them. Comparison of the two Pik proteins and Pikm suggests the importance of the CC domain in determining the resistance specificities of Pik and Pikm. This feature contrasts with that of most allelic or homologous NBS-LRR genes characterized to date, in which the major specificity determinant is believed to lie in the highly diverged LRR domain. In addition, our study revealed high evolutionary flexibility in the genome at the Pik locus, which may be relevant to the generation of new R specificities at this locus.     

Effectiveness of Ureteroscopy-Assisted Retrograde Nephrostomy (UARN) for Percutaneous Nephrolithotomy (PCNL)

Objective

To determine the impact of ureteroscopy-assisted retrograde nephrostomy (UARN) during percutaneous nephrolithotomy (PCNL).

Materials and Methods

From April 2009 to September 2011, a total of 50 patients underwent PCNL for large renal stones (stone burden >2 cm). We performed UARN in the Galdakao-modified Valdivia position for 27 patients (UARN PCNL) and ultrasonography-assisted percutaneous nephrostomy in the prone position for 23 patients (prone PCNL).

Results

UARN PCNL significantly improved the stone-free rate (81.5% vs 52.2%) and the rate of residual stones (<4 mm, 92.6% vs 65.2%, P<0.05). The median length of the operation was significantly shorter for UARN PCNL, at 160 min, compared to 299 min for prone PCNL (P<0.001). There was one intraoperative complication in prone PCNL, namely a hemorrhage that resulted in stopping the initial treatment, but it was cured conservatively. The postoperative complications included a high grade fever that persisted for three days in two UARN PCNL patients (7.4%) and six prone PCNL patients (26.1%). The Clavien grading scores showed significantly lower postoperative complications for UARN PCNL compared to prone PCNL.

Conclusion

UARN is associated with a higher stone-free rate, shorter operation time, and fewer complications during PCNL than prone PCNL.     

Differences in Salivary Alpha-Amylase and Cortisol Responsiveness following Exposure to Electrical Stimulation versus the Trier Social Stress Tests

Background

Cortisol is an essential hormone in the regulation of the stress response along the HPA axis, and salivary cortisol has been used as a measure of free circulating cortisol levels. Recently, salivary alpha-amylase (sAA) has also emerged as a novel biomarker for psychosocial stress responsiveness within the sympathetic adrenomedullary (SAM) system.

Principal Findings

We measured sAA and salivary cortisol in healthy volunteers after exposure to the Trier Social Stress Test (TSST) and electric stimulation stress. One hundred forty-nine healthy volunteers participated in this study. All subjects were exposed to both the TSST and electric stimulation stress on separate days. We measured sAA and salivary cortisol levels three times immediately before, immediately after, and 20 min after the stress challenge. The State (STAI-S) and Trait (STAI-T) versions of the Spielberger Anxiety Inventory test and the Profile of Mood State (POMS) tests were administered to participants before the electrical stimulation and TSST protocols. We also measured HF, LF and LF/HF Heart Rate Variability ratio immediately after electrical stimulation and TSST exposure. Following TSST exposure or electrical stimulation, sAA levels displayed a rapid increase and recovery, returning to baseline levels 20 min after the stress challenge. Salivary cortisol responses showed a delayed increase, which remained significantly elevated from baseline levels 20 min after the stress challenge. Analyses revealed no differences between men and women with regard to their sAA response to the challenges (TSST or electric stimulations), while we found significantly higher salivary cortisol responses to the TSST in females. We also found that younger subjects tended to display higher sAA activity. Salivary cortisol levels were significantly correlated with the strength of the applied electrical stimulation.

Conclusions

These preliminary results suggest that the HPA axis (but not the SAM system) may show differential response patterns to distinct kinds of stressors.     

Tumor cell-specific prodrugs using arsonic acid-presenting iron oxide nanoparticles with high sensitivity

We report the tumor cell-selective prodrugs based on the arsonic acid-presenting iron oxide nanoparticles. We synthesized the well-dispersed nanoparticles having arsonoacetic acid which is composed of the low toxic As(V) form. From the analyses of the reaction products, it is suggested that the reduction by dithiothreitol with arsonoacetic acid and the modified nanoparticles could generate the highly-toxic As(III) species. In the MTT assays, it was found that the cell viabilities of HeLaS3 and especially HepG2 were reduced in the presence of the modified nanoparticles. In contrast, a slight effect on viability was observed with primary mouse hepatocytes. The viabilities showed good agreements with the amounts of intracellular reduced glutathione concentrations. Furthermore, the valid concentrations of the modified nanoparticles for tumor-specific cytotoxicity were similar level in MRI measurements. These results indicate that arsonic acid-presenting nanoparticles should be a good platform for developing highly-sensitive tumor-specific prodrugs.     

CRTH2 plays an essential role in the pathophysiology of Cry j 1-induced pollinosis in mice

PGD(2) is the major prostanoid produced during the acute phase of allergic reactions. Two PGD(2) receptors have been isolated, DP and CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells), but whether they participate in the pathophysiology of allergic diseases remains unclear. We investigated the role of CRTH2 in the initiation of allergic rhinitis in mice. First, we developed a novel murine model of pollinosis, a type of seasonal allergic rhinitis. Additionally, pathophysiological differences in the pollinosis were compared between wild-type and CRTH2 gene-deficient mice. An effect of treatment with ramatroban, a CRTH2/T-prostanoid receptor dual antagonist, was also determined. Repeated intranasal sensitization with Cry j 1, the major allergen of Cryptomeria japonica pollen, in the absence of adjuvants significantly exacerbated nasal hyperresponsive symptoms, Cry j 1-specific IgE and IgG1 production, nasal eosinophilia, and Cry j 1-induced in vitro production of IL-4 and IL-5 by submandibular lymph node cells. Additionally, CRTH2 mRNA in nasal mucosa was significantly elevated in Cry j 1-sensitized mice. Following repeated intranasal sensitization with Cry j 1, CRTH2 gene-deficient mice had significantly weaker Cry j 1-specific IgE/IgG1 production, nasal eosinophilia, and IL-4 production by submandibular lymph node cells than did wild-type mice. Similar results were found in mice treated with ramatroban. These results suggest that the PGD(2)-CRTH2 interaction is elevated following sensitization and plays a proinflammatory role in the pathophysiology of allergic rhinitis, especially pollinosis in mice.     

P2Y6 receptor‐Gα12/13 signalling in cardiomyocytes triggers pressure overload‐induced cardiac fibrosis

Cardiac fibrosis, characterized by excessive deposition of extracellular matrix proteins, is one of the causes of heart failure, and it contributes to the impairment of cardiac function. Fibrosis of various tissues, including the heart, is believed to be regulated by the signalling pathway of angiotensin II (Ang II) and transforming growth factor (TGF)‐β. Transgenic expression of inhibitory polypeptides of the heterotrimeric G12 family G protein (Gα_12/13) in cardiomyocytes suppressed pressure overload‐induced fibrosis without affecting hypertrophy. The expression of fibrogenic genes (TGF‐β, connective tissue growth factor, and periostin) and Ang‐converting enzyme (ACE) was suppressed by the functional inhibition of Gα_12/13. The expression of these fibrogenic genes through Gα_12/13 by mechanical stretch was initiated by ATP and UDP released from cardiac myocytes through pannexin hemichannels. Inhibition of G‐protein‐coupled P2Y6 receptors suppressed the expression of ACE, fibrogenic genes, and cardiac fibrosis. These results indicate that activation of Gα_12/13 in cardiomyocytes by the extracellular nucleotides‐stimulated P2Y₆ receptor triggers fibrosis in pressure overload‐induced cardiac fibrosis, which works as an upstream mediator of the signalling pathway between Ang II and TGF‐β.     

Localization of laminin α3B chain in vascular and epithelial basement membranes of normal human tissues and its down-regulation in skin cancers

The basement membrane (BM) proteins laminins, which consist of alpha, beta and gamma chains, play critical roles in the maintenance of tissue structures. One of laminin alpha chains, alpha3 has two isoforms, the truncated form alpha3A and the full-sized form alpha3B. In contrast to alpha3A laminins, little is known about alpha3B laminins. To show the histological distribution of the laminin alpha3B chain, we prepared alpha3B-specific monoclonal antibodies. Immunohistochemical analysis showed that the alpha3B chain was colocalized with the alpha3A, beta3 and gamma2 chains in the epithelial BMs of the skin, esophagus, breast and lung, suggesting the presence of laminin-3B32 (laminin-5B) and laminin-3A32 (laminin-5A). In the lung alveoli, laminin-3B32 was dominant over laminin-3A32, but vice versa in other epithelial BMs. In contrast, the BMs of blood vessels including capillaries were strongly positive for alpha3B, but almost or completely negative for alpha3A, beta3 and gamma2. alpha3B was colocalized with beta1 and gamma1 in these BMs. The alpha3B chain was scarcely detected in the vessels of malignant skin cancers, though the gamma2 and beta3 chains were highly expressed in the cancer cells. These results strongly suggest that the laminin alpha3B chain is widely expressed in vascular BMs of normal tissues, probably as laminin-3B11/3B21 (laminin-6B/7B).