Growth factor- and dexamethasone-induced proteins in Swiss 3T3 cells. Relationship to DNA synthesis

Dexamethasone synergistically enhances the stimulation of DNA synthesis in quiescent Swiss 3T3 cells by cartilage-derived growth factor (CDGF) while having no consistent effect when added with platelet-derived growth factor (PDGF) or serum. We examined the hypothesis that this difference might be attributed to selective synthesis of individual proteins early in the G1 phase of the cell cycle. Swiss 3T3 cells were treated with CDGF, PDGF, and fetal bovine serum for 3 h, with or without dexamethasone, and [35S]methionine-labeled proteins were separated by two-dimensional electrophoresis on giant gels. Over 3300 proteins could be distinguished; 34 of these were consistently induced more than 3-fold by all three factors, while an additional 30 inductions were variably present. Dexamethasone by itself induced 8 other proteins, and at least 9 growth factor inductions were synergistically enhanced by addition of the hormone. To identify proteins intimately associated with growth control, we looked for inductions that reflected the dexamethasone synergy with CDGF on DNA synthesis and lack of such an effect with PDGF. The induction of only one group of proteins, the Band 1 isoforms (44-46 kDa, pI 6.1-5.9) displayed such selective synergy. The majority of the other growth factor inductions were inhibited by dexamethasone, even in the context of maximal DNA synthesis, implying that their increased synthesis is not required for growth. When 3T3 cells were treated with increasing doses of CDGF with and without dexamethasone, autoradiographic densities of induced proteins varied in a dose-responsive fashion. However, only levels of the Band 1 proteins bore a constant linear relationship to DNA synthesis, suggesting that they play an important role in early control of the cell cycle.     

Photocontrol of the GTPase activity of the small G protein K-Ras by using an azobenzene derivative

The small G protein Ras is a central regulator of cellular signal transduction processes, functioning as a molecular switch. Switch mechanisms utilizing conformational changes in nucleotide-binding motifs have been well studied at the molecular level. Azobenzene is a photochromic molecule that undergoes rapid and reversible isomerization between the cis and trans forms upon exposure to ultraviolet and visible light irradiation, respectively. Here, we introduced the sulfhydryl-reactive azobenzene derivative 4-phenylazophenyl maleimide (PAM) into the nucleotide-binding motif of Ras to regulate the GTPase activity by photoirradiation. We prepared four Ras mutants (G12C, Y32C, I36C, and Y64C) that have a single reactive cysteine residue in the nucleotide-binding motif. PAM was stoichiometrically incorporated into the cysteine residue of the mutants. The PAM-modified mutants exhibited reversible alterations in GTPase activity, nucleotide exchange rate, and interaction between guanine nucleotide exchange factor and Ras, accompanied by photoisomerization upon exposure to ultraviolet and visible light irradiation. The results suggest that incorporation of photochromic molecules into its nucleotide-binding motif enables photoreversible control of the function of the small G protein Ras.     

Suvorexant for Primary Insomnia: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials

Objective

We performed a systematic review and meta-analysis of double-blind, randomized, placebo-controlled trials evaluating suvorexant for primary insomnia.

Methods

Relevant studies were identified through searches of PubMed, databases of the Cochrane Library, and PsycINFO citations through June 27, 2015. We performed a systematic review and meta-analysis of suvorexant trial efficacy and safety outcomes. The primary efficacy outcomes were either subjective total sleep time (sTST) or subjective time-to-sleep onset (sTSO) at 1 month. The secondary outcomes were other efficacy outcomes, discontinuation rate, and individual adverse events. The risk ratio, number-needed-to-treat/harm, and weighted mean difference (WMD) and 95% confidence intervals (CI) based on a random effects model were calculated.

Results

The computerized literature database search initially yielded 48 results, from which 37 articles were excluded following a review of titles and abstracts and another eight review articles after full-text review. Thus, we identified 4 trials that included a total of 3,076 patients. Suvorexant was superior to placebo with regard to the two primary efficacy outcomes (sTST: WMD = −20.16, 95% CI = −25.01 to −15.30, 1889 patients, 3 trials, sTSO: WMD = −7.62, 95% CI = −11.03 to −4.21, 1889 patients, 3 trials) and was not different from placebo in trial discontinuations. Suvorexant caused a higher incidence than placebo of at least one side effects, abnormal dreams, somnolence, excessive daytime sleepiness/sedation, fatigue, dry mouth, and rebound insomnia.

Conclusions

Our analysis of published trial results suggests that suvorexant is effective in treating primary insomnia and is well-tolerated.     

Identification of an Interaction between VWF rs7965413 and Platelet Count as a Novel Risk Marker for Metabolic Syndrome: An Extensive Search of Candidate Polymorphisms in a Case-Control Study

Although many single nucleotide polymorphisms (SNPs) have been identified to be associated with metabolic syndrome (MetS), there was only a slight improvement in the ability to predict future MetS by the simply addition of SNPs to clinical risk markers. To improve the ability to predict future MetS, combinational effects, such as SNP—SNP interaction, SNP—environment interaction, and SNP—clinical parameter (SNP × CP) interaction should be also considered. We performed a case-control study to explore novel SNP × CP interactions as risk markers for MetS based on health check-up data of Japanese male employees. We selected 99 SNPs that were previously reported to be associated with MetS and components of MetS; subsequently, we genotyped these SNPs from 360 cases and 1983 control subjects. First, we performed logistic regression analyses to assess the association of each SNP with MetS. Of these SNPs, five SNPs were significantly associated with MetS (P < 0.05): LRP2 rs2544390, rs1800592 between UCP1 and TBC1D9, APOA5 rs662799, VWF rs7965413, and rs1411766 between MYO16 and IRS2. Furthermore, we performed multiple logistic regression analyses, including an SNP term, a CP term, and an SNP × CP interaction term for each CP and SNP that was significantly associated with MetS. We identified a novel SNP × CP interaction between rs7965413 and platelet count that was significantly associated with MetS [SNP term: odds ratio (OR) = 0.78, P = 0.004; SNP × CP interaction term: OR = 1.33, P = 0.001]. This association of the SNP × CP interaction with MetS remained nominally significant in multiple logistic regression analysis after adjustment for either the number of MetS components or MetS components excluding obesity. Our results reveal new insight into platelet count as a risk marker for MetS.     

Temporary Dietary Iron Restriction Affects the Process of Thrombus Resolution in a Rat Model of Deep Vein Thrombosis

BackgroundDeep vein thrombosis (DVT) is a major cause of pulmonary thromboembolism and sudden death. Thus, it is important to consider the pathophysiology of DVT. Recently, iron has been reported to be associated with thrombotic diseases. Hence, in this study, we investigate the effects of dietary iron restriction on the process of thrombus resolution in a rat model of DVT.MethodsWe induced DVT in 8-week-old male Sprague-Dawley rats by performing ligations of their inferior venae cavae. The rats were then given either a normal diet (DVT group) or an iron-restricted diet (DVT+IR group). Thrombosed inferior venae cavae were harvested at 5 days after ligation.ResultsThe iron-restricted diet reduced venous thrombus size compared to the normal diet. Intrathrombotic collagen content was diminished in the DVT+IR group compared to the DVT group. In addition, intrathrombotic gene expression and the activity of matrix metalloproteinase-9 were increased in the DVT+IR group compared to the DVT group. Furthermore, the DVT+IR group had greater intrathrombotic neovascularization as well as higher gene expression levels of urokinase-type plasminogen activator and tissue-type plasminogen activator than the DVT group. The iron-restricted diet decreased intrathrombotic superoxide production compared to the normal diet.ConclusionsThese results suggest that dietary iron restriction affects the process of thrombus resolution in DVT.     

Advanced Application of Porcine Intramuscular Adipocytes for Evaluating Anti-Adipogenic and Anti-Inflammatory Activities of Immunobiotics

We previously established a clonal porcine intramuscular preadipocyte (PIP) line and we were able to establish a protocol to obtain functional mature adipocytes from PIP cells. We hypothesized that both PIP cells and mature adipocytes are likely to be useful in vitro tools for increasing our understanding of immunobiology of adipose tissue, and for the selection and study of immunoregulatory probiotics (immunobiotics) able to modulate adipocytes immune responses. In this study, we investigated the immunobiology of PIP cells and mature adipocytes in relation to their response to TNF-α stimulation. In addition, we evaluated the possibility that immunobiotic microorganisms modify adipogenesis and immune functions of porcine adipose tissue through Peyer’s patches (PPs) immune-competent cells. We treated the porcine PPs immune cells with different probiotic strains; and we evaluated the effect of conditioned media from probiotic-stimulated immune cells in PIP cells and mature adipocytes. The Lactobacillus GG and L. gasseri TMC0356 showed remarkable effects, and were able to significantly reduce the expression of pro-inflammatory factors and negative regulators (A20, Bcl-3, and MKP-1) in adipocytes challenged with TNF-α. The results of this study demonstrated that the evaluation of IL-6, and MCP-1 production, and A20 and Bcl-3 down-regulation in TNF-α-challenged adipocytes could function as biomarkers to screen and select potential immunobiotic strains. Taking into consideration that several in vivo and in vitro studies clearly demonstrated the beneficial effects of Lactobacillus GG and L. gasseri TMC0356 in adipose inflammation, the results presented in this work indicate that the PIP cells and porcine adipocytes could be used for the screening and the selection of new immunobiotic strains with the potential to functionally modulate adipose inflammation when orally administered.     

Intranasal Immunization with DOTAP Cationic Liposomes Combined with DC-Cholesterol Induces Potent Antigen-Specific Mucosal and Systemic Immune Responses in Mice

Despite the progress made by modern medicine, infectious diseases remain one of the most important threats to human health. Vaccination against pathogens is one of the primary methods used to prevent and treat infectious diseases that cause illness and death. Vaccines administered by the mucosal route are potentially a promising strategy to combat infectious diseases since mucosal surfaces are a major route of entry for most pathogens. However, this route of vaccination is not widely used in the clinic due to the lack of a safe and effective mucosal adjuvant. Therefore, the development of safe and effective mucosal adjuvants is key to preventing infectious diseases by enabling the use of mucosal vaccines in the clinic. In this study, we show that intranasal administration of a cationic liposome composed of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 3β-[N-(N'',N''-dimethylaminoethane)-carbamoyl] (DC-chol) (DOTAP/DC-chol liposome) has a potent mucosal adjuvant effect in mice. Intranasal vaccination with ovalbumin (OVA) in combination with DOTAP/DC-chol liposomes induced the production of OVA-specific IgA in nasal tissues and increased serum IgG1 levels, suggesting that the cationic DOTAP/DC-chol liposome leads to the induction of a Th2 immune response. Additionally, nasal-associated lymphoid tissue and splenocytes from mice treated with OVA plus DOTAP/DC-chol liposome showed high levels of IL–4 expression. DOTAP/DC-chol liposomes also enhanced OVA uptake by CD11c⁺ dendritic cells in nasal-associated lymphoid tissue. These data demonstrate that DOTAP/DC-chol liposomes elicit immune responses via an antigen-specific Th2 reaction. These results suggest that cationic liposomes merit further development as a mucosal adjuvant for vaccination against infectious diseases.