Two In-based organic-inorganic hybrid compounds with reversible phase transition derived from the order-disorder changes of cations or anions

Solid-state phase transition materials have received extraordinary interest due to their rich physical properties, such as thermal, dielectric, and ferroelectric properties. Here, two In-based organic-inorganic hybrid compounds, (C₆H₅CH₂CH₂NH₃)₃[InBr₅(H₂O)] (1) and [(C₃H₇)₄N][InCl₄] (2), both display reversible phase transition and dielectric response. Differential scanning calorimetry measurements indicate that the phase transition temperatures (T_c) of 1 and 2 are 167 K and 351 K, respectively. Moreover, structural analyses disclose that the phase transition of 1 can be attributed to the order-disorder changes of phenethylammonium organic cations whereas the phase transition of 2 is caused by the order-disorder changes of [InCl₄]^- anions. The phase transitions of In-based organic-inorganic hybrid compounds can be driven by the order-disorder changes of cations or anions. Therefore, the system of In-based organic-inorganic hybrid compounds is very suitable for exploring organic-inorganic hybrid phase transition materials.

Anti-inflammatory effects of oroxylin A on RAW 264.7 mouse macrophages induced with polyinosinic-polycytidylic acid

Oroxylin A (5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one; Baicalein 6-methyl ether) is an active flavonoid compound originally isolated from Scutellaria radix, which has been used to treat pulmonary infection in Korea, China, and Japan. Oroxylin A is known to possess dopamine reuptake inhibitor activity. However, the effects of oroxylin A on virus-induced macrophages has not been fully elucidated. In the present study, the anti-inflammatory effects of oroxylin A on double-stranded RNA-induced macrophages were examined. Production of nitric oxide (NO), various cytokines, as well as calcium release and the mRNA expression of signal transducer and activator of transcription 1 (STAT1) in dsRNA polyinosinic-polycytidylic acid (PIC)-induced RAW 264.7 mouse macrophages were evaluated. Oroxylin A restored the cell viability in PIC-induced RAW 264.7 mouse macrophages at concentrations of up to 50 µM. Additionally, oroxylin A significantly inhibited the production of nitric oxide (NO), interleukin (IL)-1α, IL-1β, IL-6, IL-10, interferon gamma-induced protein 10, granulocyte-colony stimulating factor (CSF), granulocyte macrophage-CSF, leukemia inhibitory factor (IL-6 class cytokine), lipopolysaccharide-induced CXC chemokine (LIX), monocyte chemoattractant protein 1, macrophage inflammatory protein (MIP)-1α, MIP-1β, MIP-2, Regulated on Activation, Normal T Expressed and Secreted, tumor necrosis factor-α, and vascular endothelial growth factor as well as calcium release and the mRNA expression of STAT1 in PIC-induced RAW 264.7 cells (P<0.05). Thus, the present results suggest that oroxylin A has anti-inflammatory properties, associated with its inhibition of NO, cytokines, chemokines and growth factors in PIC-induced macrophages via the calcium-STAT pathway.

Anti-Inflammatory Effect of Wogonin on RAW 264.7 Mouse Macrophages Induced with Polyinosinic-Polycytidylic Acid

Wogonin (5,7-dihydroxy-8-methoxyflavone) is an active flavonoid compound originally isolated from Scutellaria radix, which has been used to treat lung inflammation in Korea, China, and Japan. Wogonin has been known to inhibit inducible nitric oxide synthase and have the anti-tumor properties. However, the effects of wogonin on virus-induced macrophages are not fully reported. In this study, the anti-inflammatory effect of wogonin on double-stranded RNA (dsRNA)-induced macrophages was examined. Wogonin restored the cell viability in dsRNA [polyinosinic-polycytidylic acid]-induced RAW 264.7 mouse macrophages at concentrations of up to 50 μM. Wogonin significantly inhibited the production of nitric oxide, IL-1α, IL-1β, IL-6, IL-10, IP-10, G-CSF, GM-CSF, LIF (IL-6 class cytokine), LIX/CXCL5, MCP-1, M-CSF, MIP-1α, MIP-1β, MIP-2, RANTES/CCL5, TNF-α, and VEGF as well as calcium release and mRNA expression of signal transducer and activated transcription 1 (STAT1) and STAT3 in dsRNA-induced RAW 264.7 cells (P < 0.05). In conclusion, wogonin has anti-inflammatory properties related with its inhibition of nitric oxide, cytokines, chemokines, and growth factors in dsRNA-induced macrophages via the calcium-STAT pathway.

Transforming growth factor β and severe asthma: a perfect storm

Asthma is a chronic inflammatory airway disease involving complex interplay between resident and infiltrative cells, which in turn are regulated by a wide range of host mediators. Identifying useful biomarkers correlating with clinical symptoms and degree of airway obstruction remain important to effective future asthma treatments. Transforming growth factor β (TGF-β) is a major mediator involved in pro-inflammatory responses and fibrotic tissue remodeling within the asthmatic lung. Its role however, as a therapeutic target remains controversial. The aim of this review is to highlight its role in severe asthma including interactions with adaptive T-helper cells, cytokines and differentiation through regulatory T-cells. Associations between TGF-β and eosinophils will be addressed and the effects of genetic polymorphisms of the TGF-β1 gene explored in the context of asthma. We highlight TGF-β1 as a potential future therapeutic target in severe asthma including its importance in identifying emerging clinical phenotypes in asthmatic subjects who may be suitable for individualized therapy through TGF-β modulation.

The molecular mechanisms of regulatory T cell immunosuppression

CD4⁺CD25⁺Foxp3⁺ T lymphocytes, known as regulatory T cells or T(regs), have been proposed to be a lineage of professional immune suppressive cells that exclusively counteract the effects of the immunoprotective "helper" and "cytotoxic" lineages of T lymphocytes. Here we discuss new concepts on the mechanisms and functions of T(regs). There are several key points we emphasize: 1. Tregs exert suppressive effects both directly on effector T cells and indirectly through antigen-presenting cells; 2. Regulation can occur through a novel mechanism of cytokine consumption to regulate as opposed to the usual mechanism of cytokine/chemokine production; 3. In cases where CD4⁺ effector T cells are directly inhibited by T(regs), it is chiefly through a mechanism of lymphokine withdrawal apoptosis leading to polyclonal deletion; and 4. Contrary to the current view, we discuss new evidence that T(regs), similar to other T-cells lineages, can promote protective immune responses in certain infectious contexts (Chen et al., 2011; Pandiyan et al., 2011). Although these points are at variance to varying degrees with the standard model of T(reg) behavior, we will recount developing findings that support these new concepts.