DataSheet1_A novel near-infrared fluorescent probe for rapid sensing of HClO in living cells and zebrafish.docx

Reactive oxygen species (ROS) are significant active species in living organisms, and their coordination maintains the function of organelles to resist the invasion of foreign substances. Hypochlorous acid (HClO) is not only an eventful signaling species but also a kind of ROS, which plays an irreplaceable role in the immune system. However, its abnormal levels can cause cell damage or even apoptosis, which in turn leads to the onset of a series of diseases such as inflammation, neurological diseases, and even cancer. Based on this, we designed a near-infrared fluorescent probe with a large Stokes shift for ultrafast response to HClO. Furthermore, the probe exhibits excellent sensitivity and selectivity toward HClO over other species. The probe was successfully applied to visualize endogenous and exogenous HClO in living cells and in zebrafish. This unique study is the key to providing a trustworthy tool for imaging based on the in vitro and in vivo imaging of endogenous HClO, which possesses great potential for the use in future studies of HClO-related biology and pathology.</p

Chronic Ingestion of H1-Antihistamines Increase Progression of Atherosclerosis in Apolipoprotein E-/- Mice

<div><p>Although increased serum histamine levels and H1R expression in the plaque are seen in atherosclerosis, it is not known whether H1R activation is a causative factor in the development of the disease, or is a host defense response to atherogenic signals. In order to elucidate how pharmacological inhibition of histamine receptor 1 (H1R) signaling affects atherogenesis, we administered either cetirizine (1 and 4 mg/kg. b.w) or fexofenadine (10 and 40 mg/kg. b.w) to <i>ApoE^−/−</i> mice maintained on a high fat diet for three months. Mice ingesting a low dose of cetirizine or fexofenadine had significantly higher plaque coverage in the aorta and cross-sectional lesion area at the aortic root. Surprisingly, the higher doses of cetirizine or fexofenadine did not enhance atherosclerotic lesion coverage over the controls. The low dose of fexofenadine, but not cetirizine, increased serum LDL cholesterol. Interestingly, the expression of iNOS and eNOS mRNA was increased in aortas of mice on high doses of cetirizine or fexofenadine. This may be a compensatory nitric oxide (NO)-mediated vasodilatory mechanism that accounts for the lack of increase in the progression of atherosclerosis. Although the administration of cetirizine did not alter blood pressure between the groups, there was a positive correlation between blood pressure and lesion/media ratio at the aortic root in mice receiving the low dose of cetirizine. However, this association was not observed in mice treated with the high dose of cetirizine or either doses of fexofenadine. The macrophages or T lymphocytes densities were not altered by low doses of H1-antihistamines, whereas, high doses decreased the number of macrophages but not T lymphocytes. The number of mast cells was decreased only in mice treated with low dose of fexofenadine. These results demonstrate that chronic ingestion of low therapeutic doses of cetirizine or fexofenadine enhance progression of atherosclerosis.</p></div

Effect of low doses of cetirizine and fexofenadine on CD36 expression.

<p>Representative immunohistochemical images (A–C, magnification at 200x) of scavenger receptor CD36 are presented. Placebo (Pl), cetirizine low (C.L), fexofenadine low (F.L). No significant difference in the intensity was noted between groups by a grading of scale zero to three.</p

Effect of H1-antihistamines on levels of prostanoids and histamine.

<p>24-h urine samples were analyzed for the concentration of stable metabolites of TxA₂ (A), PGI₂ (B) by GC-MS or EIA. Urinary levels of histamine were measured by EIA (C). Results shown are mean ± SEM. n =  4 to 12. None of the parameters found to be significant.</p

Correlation of blood pressure variables with plaque to media ratio.

<p>Correlation analyses between systolic, diastolic and arterial mean pressure values with the intima/media ratio of placebo, Pl (A), cetirizine low, C.L (B), cetirizine high, C.H (C), fexofenadine low, F.L (D) and fexofenadine high, F.H (E). The “<i>p</i>” values and Pearson “r” values are given for each graph. “n” = 9 for panel A; “n” = 8 for panel B and E, and “n” = 6 for panel C and D.</p

Serum cytokines.

<p>Serum cytokines were determined by cytokine array commercially at IDEXX Preclinical Research Services. Each value is mean <b>±</b> SEM *<i>p</i><0.05.</p

Blood pressure, heart rate and blood flow rate of <i>ApoE^−/−</i> mice treated with H1-antihistamines.

<p>The blood pressure was monitored using non-invasive tail cuff method. Each value is mean ± SEM.</p

Effect of H1-antihistamines on the expression of COX1, COX2, iNOS, eNOS and Egr1 mRNA in aorta.

<p>Aortic tissues harvested from three or four mice from each group were analyzed for mRNA expression by qRT-PCR. Each gene amplicon was normalized for the β-actin expression. Placebo (Pl), cetirizine low (C.L), cetirizine high (C.H), fexofenadine low (F.L) and fexofenadine high (F.H). Data presented are mean ± SEM of the fold change compared to control values. *<i>p</i><0.05 vs. controls.</p

Effect of H1-antihistamines on atherosclerotic plaque development in the aorta.

<p><i>ApoE^−/−</i>^mice maintained on a high fat diet were administered with cetirizine (1 and 4 mg/kg b.w) or fexofenadine (10 and 40 mg/kg b.w.) for 3 months in the drinking water. <i>ApoE^−/−</i> mice receiving plain water served as placebo controls. Pl, placebo; C.L, cetirizine low; C.H, cetirizine high; F.L, fexofenadine low; F.H, fexofenadine high. Panel (A) represents images of <i>en face</i> preparations and (B) is the quantification of the percentage area of plaque coverage in the aorta. Representative images of the H & E stained cross-sections of the aortic root (C), and quantification of lesion area at the aortic root (D). Ao, aorta; PuAo, pulmonary artery. The “n” for Pl and C.L is the sum of mice used in three independent experiments. The “n” for C.H, F.L and F.H derived from a single experiment. Data points presented in B and D are mean ± SEM. *<i>p</i><0.05 vs. control.</p

Effect of H1-antihistamines on H1R expression in atherosclerotic plaques.

<p>Atherosclerotic lesions around the aortic root of <i>ApoE^−/−</i> mice were subjected to immunohistochemical analyses for H1R expression with anti-H1R (green) and DAPI (nuclear stain-blue). Panel (A) represents immunoflourescent staining for placebo (Pl), cetirizine low (C.L), cetirizine high (C.H), fexofenadine low (F.L) and fexofenadine high (F.H). Panel (B) depicts the integrated density of H1R staining. Magnification 40× at objective. n = 4.</p