Thalidomide prevents bleomycin-induced pulmonary fibrosis in mice

Pulmonary fibrosis in humans can occur as a result of a large number of conditions. In idiopathic pulmonary fibrosis (IPF), pulmonary function becomes progressively compromised resulting in a high mortality rate. Currently there are no proven effective treatments for IPF. We have recently reported that IL-6 and TGF-beta(1) plays an important role in proliferation and differentiation of lung fibroblasts, and all-trans-retinoic acid (ATRA) prevented bleomycin-induced lung fibrosis through the inhibition of these cytokines. Thalidomide (Thal) has been used in the treatment of multiple myeloma through the inhibitory effect on IL-6-dependent cell growth and angiogenesis. In this study, we examined the preventive effect of Thal on bleomycin-induced pulmonary fibrosis in mice. We performed histological examinations and quantitative measurements of IL-6, TGF-beta(1), collagen type Ialpha1 (COL1A1), vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) in bleomycin-treated mouse lung tissues with or without the administration of Thal. Thal histologically ameliorated bleomycin-induced fibrosis in mouse lung tissues. Thal decreased the expressions of IL-6, TGF-beta(1), VEGF, Ang-1 Ang-2, and COL1A1 mRNA in mouse lung tissues. In addition, Thal inhibited angiogenesis in the lung. In vitro studies disclosed that Thal reduced 1) production of IL-6, TGF-beta(1), VEGF, Ang-1, and collagen synthesis from human lung fibroblasts, and 2) both IL-6-dependent proliferation and TGF-beta(1)-dependent transdifferentiation of the cells, which could be the mechanism underlying the preventive effect of Thal on pulmonary fibrosis. These data may provide a rationale to explore clinical use of Thal for the prevention of pulmonary fibrosis.     

Effects of forskolin on inotropic performance and phospholamban phosphorylation in exercise-trained hypertensive myocardium.

Beta-adrenergic receptor (beta-AR) responsiveness is downregulated in left ventricular (LV) hypertrophy induced by chronic hypertension. While exercise training in hypertension enhances beta-AR responsiveness, the role of adenylyl cyclase remains unclear. The purpose of the present study was to test whether treadmill running in the spontaneously hypertensive rat (SHR) model improves LV responsiveness to forskolin (FOR) or the combination of FOR + isoproterenol (FOR+ISO). Female SHR (16-wk) were randomly placed into sedentary (SHR-SED; n = 7) or treadmill-trained (SHR-TRD; n = 8) groups. Wistar-Kyoto (WKY; n = 7) animals acted as normotensive controls. Langendorff, isovolumic LV performance was established at baseline and during incremental FOR infusion (1 and 5 micromol/l) and FOR+ISO (5 micromol/l + 1x10(-8) mol/l). Heart rate, systolic blood pressure, and heart-to-body weight ratio were lower in WKY relative to both SHR groups (P < 0.05). LV performance and heart rate significantly increased in all groups to a similar extent with incremental FOR infusion. However, in the presence of 5 micromol/l FOR, ISO increased LV developed pressure, positive change in LV pressure, and negative change in LV pressure to a greater extent in SHR-TRD relative to SHR-SED (P < 0.05). Phospholamban phosphorylation at the Thr17 was greater in SHR-TRD relative to SHR-SED and WKY (P < 0.05). Absolute LV developed pressure was moderately correlated with phospholamban phosphorylation at both the Ser16 (r = 0.64; P < 0.05) and Thr17 (r = 0.52; P < 0.05). Our data suggest that the adenylyl cyclase step in the beta-AR cascade is not downregulated in the early course of hypertension and that the enhanced beta-AR responsiveness with training is likely mediated at levels other than adenylyl cyclase. Our data also suggest that beta-AR inotropic responsiveness in the presence of direct adenylyl cyclase agonism is improved in trained compared with sedentary SHR hearts.     

Therapeutic potential of stem/progenitor cells in human skeletal muscle for cardiovascular regeneration

Although myoblast transplantation in patients with ischemic heart failure results in a significant improvement of cardiac function, subsequent studies have consistently shown the myotubes formation in the absence of electromechanical coupling with the neighboring host myocardium, accompanied with the short-term release of paracrine effectors from implanted cells. One major pitfall of using myoblasts is that transplanted cells do not differentiate into cardiomyocytes, which may cause the inherent proarrhythmogenic events. Therefore, whether a discrete subpopulation in heterogeneous muscle-cell cultures is responsible for substantial cardiovascular regeneration has yet to be investigated. We describe here the isolation of progenitor cells from human skeletal muscle. These cells proliferated as non-adherent myospheres in suspension and displayed early embryonic factors and mesenchymal cell-like characteristics. Flow cytometric analyses demonstrated that CD56/N-CAM/Leu-19, a neural cell adhesion molecule abundantly present in myoblasts, was absent in myospheres but was expressed in an adherent cell population containing myogenic precursors. Myosphere-derived progenitor cells (MDPCs) differentiated in culture to produce cardiac, smooth muscle, and endothelial cells. Transplantation of MDPCs into ischemic hearts in NOD/scid mice promoted angiogenesis with substantial cardiovascular regeneration. Our results provide a foundation to further study the cell and biological function of human MDPCs which may have potential therapeutic implications.     

Genome-Wide Association Study Identifies Novel Pharmacogenomic Loci For Therapeutic Response to Montelukast in Asthma

Background

Genome-wide association study (GWAS) is a powerful tool to identify novel pharmacogenetic single nucleotide polymorphisms (SNPs). Leukotriene receptor antagonists (LTRAs) are a major class of asthma medications, and genetic factors contribute to variable responses to these drugs. We used GWAS to identify novel SNPs associated with the response to the LTRA, montelukast, in asthmatics.

Methods

Using genome-wide genotype and phenotypic data available from American Lung Association - Asthma Clinical Research Center (ALA-ACRC) cohorts, we evaluated 8-week change in FEV₁ related to montelukast administration in a discovery population of 133 asthmatics. The top 200 SNPs from the discovery GWAS were then tested in 184 additional samples from two independent cohorts.

Results

Twenty-eight SNP associations from the discovery GWAS were replicated. Of these, rs6475448 achieved genome-wide significance (combined P = 1.97 x 10^-09), and subjects from all four studies who were homozygous for rs6475448 showed increased ΔFEV₁ from baseline in response to montelukast.

Conclusions

Through GWAS, we identified a novel pharmacogenomic locus related to improved montelukast response in asthmatics.     

An Essential Role of the Arginine Vasotocin System in Mate-Guarding Behaviors in Triadic Relationships of Medaka Fish (Oryzias latipes)

To increase individual male fitness, males of various species remain near a (potential) mating partner and repel their rivals (mate-guarding). Mate-guarding is assumed to be mediated by two different types of motivation: sexual motivation toward the opposite sex and competitive motivation toward the same sex. The genetic/molecular mechanisms underlying how mate presence affects male competitive motivation in a triadic relationship has remained largely unknown. Here we showed that male medaka fish prominently exhibit mate-guarding behavior. The presence of a female robustly triggers male-male competition for the female in a triadic relationship (2 males and 1 female). The male-male competition resulted in one male occupying a dominant position near the female while interfering with the other male''s approach of the female. Paternity testing revealed that the dominant male had a significantly higher mating success rate than the other male in a triadic relationship. We next generated medaka mutants of arginine-vasotocin (avt) and its receptors (V1a1, V1a2) and revealed that two genes, avt and V1a2, are required for normal mate-guarding behavior. In addition, behavioral analysis of courtship behaviors in a dyadic relationship and aggressive behaviors within a male group revealed that avt mutant males displayed decreased sexual motivation but showed normal aggression. In contrast, heterozygote V1a2 mutant males displayed decreased aggression, but normal mate-guarding and courtship behavior. Thus, impaired mate-guarding in avt and V1a2 homozygote mutants may be due to the loss of sexual motivation toward the opposite sex, and not to the loss of competitive motivation toward rival males. The different behavioral phenotypes between avt, V1a2 heterozygote, and V1a2 homozygote mutants suggest that there are redundant systems to activate V1a2 and that endogenous ligands activating the receptor may differ according to the social context.     

NGF-potentiating vibsane-type diterpenoids from Viburnum sieboldii

Six new vibsane-type diterpenoids, named neovibsanin O (1), neovibsanin M (2), neovibsanin L (3), (8Z)-neovibsanin M (4), 15-O-methylvibsanin H (5), and 5-epi-15-O-methylvibsanin H (6), were isolated from the leaves of Viburnum sieboldii by bioassay-guided fractionation using NGF-differentiated PC12 cells. The structures of 1–6 were established by analyzing their spectroscopic data and comparing their NMR data with those of previously reported vibsane-type diterpenoids. Compounds 3 and 4, and the known vibsane-type diterpenoids neovibsanins A (7) and B (8) significantly enhanced the neurite outgrowth of NGF-mediated PC12 cells at concentrations ranging from 20 to 40 μM.