An allergenic plant calmodulin from Artemisia pollen primes human DCs leads to Th2 polarization.

Artemisia pollen is the major cause of seasonal allergic respiratory diseases in the northern hemisphere. About 28.57% of Artemisia allergic patients' IgE can recognize ArtCaM, a novel allergenic calmodulin from Artemisia identified in this study. These patients exhibited stronger allergic reactions and a longer duration of allergic symptoms. However, the signaling mechanism that triggers these allergic reactions is not fully understood. In this study, we found that extracellular ArtCaM directly induces the maturation of human dendritic cells (DCs), which is attributed to a series of Ca2+ relevant cascades, including Ca2+/NFAT/CaMKs. ArtCaM alone induces inflammatory response toward Th1, Th17, and Treg. Interestingly, a combination of ArtCaM and anti-ArtCaM IgE led to Th2 polarization. The putative mechanism is that anti-ArtCaM IgE partially blocks the ArtCaM-induced ERK signal, but does not affect Ca2+-dependent cascades. The crosstalk between ERK and Ca2+ signal primes DCs maturation and Th2 polarization. In summary, ArtCaM related to clinical symptoms when combined with anti-ArtCaM IgE, could be a novel allergen to activate DCs and promote Th2 polarization. Such findings provide mechanistic insights into Th2 polarization in allergic sensitization and pave the way for novel preventive and therapeutic strategies for efficient management of such pollen allergic disease.

Manipulation of living cells with 450 nm laser photobiomodulation.

Increasing studies demonstrated that photobiomodulation (PBM) influenced specific biological effects in cells, tissues and organs, and these effects rely on the production of light irradiation. In this study, we aimed to precisely manipulate the spatial arrangement of adhesion cells in a traditional culture condition with 450 nm low intensity laser. Through 450 nm laser PBM, the adhesion of the cultured cells was significantly improved and resisted the digestion of 0.1% trypsin. Combined with a computer aided design system (CAD) and computer numerical control (CNC) system, the designed laser irradiation pattern induced the specific cell micropattern in the culture dish. RNA sequencing and biochemical experiments confirmed that the 450 nm laser prompted low-density lipoprotein (LDL) bonding to the cell surface and induced lipid peroxidation, which crosslinked and modified the protein molecules on the irradiated cell surface. In this way, the peroxidation product-modified proteins resisted trypsin proteolysis, ultimately leading to a differential detachment between the irradiated and non-irradiated cells under trypsin treatment. This convenient method did not require special biomaterial processing, has no impact on cell viability and functions, and required no changes to the conventional cell culture conditions. The photo-induced cell capturing is a great complement to existing tools by providing spatial resolution.

42 °C heat stress pretreatment protects human melanocytes against 308-nm laser-induced DNA damage in vitro.

Vitiligo is a common depigment of skin disorder due to loss of functional melanocytes. Recently, the phototherapy with a 308-nm xenon-chloride excimer laser (UVB laser) is wildly used in vitiligo treatment. However, excessive UVB will induce photo-damage and photo-carcinogenesis in melanocytes. Previous studies revealed a protective effect of heat on UVB-induced melanocyte damage. In this study, we combined heat stress pretreatment with UVB to evaluate whether heat stress pretreatment has an ameliorative effect on UVB-induced damage. Human primary melanocytes (HMCs) were cultured and irradiated with a 308-nm laser with/without heat treatment. MTT assay, apoptosis analysis, and comet assay were conducted to monitor the damage of HMCs. Western blot and immunofluorescence staining were performed to assess the expression and subcellular localization of HSP70. HMCs heated at 42 °C for 1 h exhibit no cytotoxicity. Furthermore, preheat treatment attenuated the UVB laser-induced injury, reduced the DNA damage, and attenuated the cell apoptosis. The level and the localization of HSP70 determined the protective effects against UVB-induced DNA damage. Combining preheat treatment with a 308-nm xenon-chloride excimer laser would be a potential therapeutic method not only promotes the repigment of vitiligo but also reduces the UVB-induced photo-damage.

Puerarin inhibits iNOS, COX-2 and CRP expression via suppression of NF-κB activation in LPS-induced RAW264.7 macrophage cells.

Puerarin (7,4'-dihydroxy-8-C-glucosylisoflavone) is the most abundant isoflavone-C-glucoside extracted from Radix puerariae, and it has been used for various medicinal purposes in traditional oriental medicine for thousands of years. In the present study, the ability of the puerarin to modulate inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and C reactive protein (CRP) expression and induce changes in the nuclear factor κB (NF-κB) pathway in RAW264.7 macrophage cells was examined. The protein and mRNA levels of lipopolysaccharide (LPS)-induced iNOS, COX-2 and CRP were determined in RAW246.7 macrophage cells. Inhibitor κB (I-κB) phosphorylation and p65NF-κB expression in RAW246.7 macrophage cells were also detected under our experimental conditions. The results indicated that puerarin inhibited the expression of LPS-induced iNOS, COX-2 and CRP proteins and also suppressed their mRNAs from RT-PCR experiments in RAW264.7 cells. Subsequently, we determined that the inhibition of iNOS, COX-2 and CRP expression was due to a dose-dependent inhibition of phosphorylation and degradation of I-κB, which resulted in the reduction of p65NF-κB nuclear translocation. These data suggested that the effect of puerarin-mediated inhibition of LPS-induced iNOS, COX-2 and CRP expression is attributed to suppressed NF-κB activation at the transcriptional level.

Puerarin inhibits C-reactive protein expression via suppression of nuclear factor kappaB activation in lipopolysaccharide-induced peripheral blood mononuclear cells of patients with stable angina pectoris.

Puerarin (4'-7-dihydroxy-8-beta-D-glucosylisoflavone), the most abundant isoflavone-C-glucoside extracted from the root of the plant Pueraria lobata, has demonstrated anti-inflammatory activity in cellular models of inflammation. In this report, we examined the ability of puerarin to modulate C-reactive protein (CRP) expression and key molecules in the nuclear factor kappa B (NF-kappaB) pathway to determine its molecular target. The protein and mRNA levels of CRP were determined in lipopolysaccharide (LPS)-induced peripheral blood mononuclear cells of patients with unstable angina pectoris. Also, we detected the I-kappaBalpha phosphorylation and the p65NF-kappaB expression in peripheral blood mononuclear cells under our experimental condition. The results indicated that puerarin inhibited the expression of the protein and mRNA levels of CRP in LPS-induced peripheral blood mononuclear cells. Subsequently, we determined that the inhibition of CRP expression was because of a dose-dependent inhibition of phosphorylation and degradation of inhibitor kappaB(I-kappaB), which resulted in a reduction of p65NF-kappaB nuclear translocation. We conclude that puerarin acts as an anti-inflammatory agent by blocking NF-kappaB signalling, and may possibly be developed as a useful agent for the chemoprevention of atherosclerosis.