[Study on the damage of the tight junctions of nasal mucosal epithelial cells by artemisia annua pollen].

Objective: To investigate the damage and mechanism of artemisia annua pollen on tight junction of human nasal mucosa epithelial cells (HNEpC). Methods: HNEpC were cultured in vitro. Different concentrations of artemisia annua pollen (0, 20, 40, 80, 100, 160, 200 µg/ml) were used to intervene the cells for 24 h, and the cell proliferation activity was detected by the CCK-8 method. The expression and phosphorylation of p38MAPK signaling pathway were detected by Western Blot before and after the intervention of SB203580, a p38MAPK inhibitor in HNEpC. Immunofluorescence chemical staining, Western Blot and quantitative real-time PCR (qPCR) were used to observe the expression and distribution of tight junctions Occludin and Claudin-1. SPSS 21.1 software was used for statistical analysis. Results: CCK-8 results showed that, compared with the control group, the proliferation activity of HNEpC increased after 6 h intervention with different concentrations of artemisia annua pollen (all P<0.05). After 12 h of intervention, the proliferation activity of HNEpC in the 20, 40, 80, 100 and 160 µg/ml groups was not significantly changed (all P>0.05), while that in the 200 µg/ml group was decreased (P<0.05). After the intervention for 24 h, the proliferation activity of cells in the 20 and 40 µg/ml groups was not significantly changed (all P>0.05), while that in the 80, 100, 160 and 200 µg/ml groups was decreased (all P<0.05). Immunofluorescence staining showed that the Occludin and Claudin-1 proteins in the normal control group were localized on the cell membrane and expressed more and formed a ring structure around the cell membrane. However, under the intervention of high concentration artemisia annua pollen, its expression level decreased, appeared broken, fuzzy, and nonuniform distribution. Western Blot and qPCR results showed that after 24 h of intervention, the expression levels of HNEpC Claudin-1 protein and its mRNA in the pollen groups (40, 80, 100, 160, 200 µg/ml) of artemisia annua decreased compared with those of those of the control group (mRNA expression levels were 0.567±0.214, 0.443±0.109, 0.462±0.160, 0.497±0.134, 0.388±0.076 compared with 1.001±0.067, respectively, all P<0.05). However, the mRNA of Occludin protein and its mRNA only decreased in the 200 µg/ml treatment group (mRNA expression level was 0.631±0.109 compared with 1.016±0.026, P<0.05), while all the other treatment groups increased (mRNA expression levels were 1.258±0.134, 1.827±0.103, 2.429±0.077, 1.707±0.085, 1.477±0.066 compared with 1.016±0.026, respectively, all P<0.05). Western Blot showed that p-p38MAPK expression increased after intervention with 100, 160, 200 µg/ml artemisia annua pollen for 24 h. SB203580 could inhibit the decreasing expression of Occludin caused by artemisinin pollen (mRNA expression was 1.255±0.179 compared with 0.631±0.109, P<0.05), but had no effect on Claudin-1 protein expression. Conclusion: Pollen from artemisia annua may activate p38MAPK signaling pathway and destroy the close connection of HNEpC.

Role of Zinc Sulphate in Immune Regulation in Artemisia annua Pollen-challenged P815 Mastocytoma Cells.

Objective This study aimed to investigate the role of zinc sulphate in immune regulation in Artemisia annua pollen-challenged P815 mastocytoma cells. Methods P815 mastocytoma cells were treated with various concentrations of zinc sulphate and Artemisia annua pollen. Cell proliferation was measured using the Cell Counting Kit-8. The amount of ST2 and p38 in the cells were measured using Western blotting. The level of interleukins (IL)-33 in the supernatant was determined using the enzyme-linked immunosorbent assay. The levels of IL-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor were measured using the cytometric bead array. Results Artemisia annua pollen at a concentration >0.001 µg/mL induced allergic response in the P815 mastocytoma cells. Expressions of IL-33, IL-4, ST2, and p38 increased along with higher concentrations of Artemisia annua pollen. Zinc sulphate of 50-200 µmol/L promoted the proliferation of P815 mastocytoma cells. Zinc sulphate attenuated the upregulation of IL-33, IL-4, ST2, and p38 caused by Artemisia annua pollen. Conclusion Zinc sulphate can promote the proliferation of P815 mastocytoma cells. It can also attenuate allergic response in the P815 mastocytoma cells induced by Artemisia annua pollen, which might provide a new treatment method for allergic diseases.

A non-pharmaceutical form of Artemisia annua is not effective in preventing Plasmodium falciparum malaria.

Non-pharmaceutical forms of Artemisia annua (a Chinese plant containing artemisinin) are used by some travellers who believe these products are safer than anti-malarial drugs. We report two cases of severe Plasmodium falciparum malaria requiring hospitalization in an Intensive Care Unit following prophylaxis with non-pharmaceutical A. annua in French travellers.