Laboratory for Investigation in Ophthalmology (LIM-33), University of São Paulo Medical School, São Paulo. Av.Dr. Arnaldo 455, 2nd Floor, 2113, São Paulo, SP, Brazil.
Laboratory of Experimental Air Pollution (LPAE), University of São Paulo Medical School, São Paulo. Av. Dr. Arnaldo 455, 1st Floor, 1304, São Paulo, SP, Brazil; Environmental Exposure and Risk Assessment Group, Collective Health Post-Graduation Program, Catholic University of Santos, Av. Conselheiro Nébias 300, Office 106, Santos, SP, Brazil.
Exp Eye Res. 2020 Jan;190:107889. doi: 10.1016/j.exer.2019.107889. Epub 2019 Dec 1.
Pre-harvest burning of sugarcane fields produces large amounts of air pollutants which are known to cause health problems, including ocular surface abnormalities. In this study, we evaluated the effect of biomass burning on mucus quality and mucin gene expression (MUC1, MUC5AC, MUC16) in the conjunctiva of sugarcane workers (SWs) and residents of an adjacent town (RTs). Impression cytology samples of the inferior tarsal and bulbar conjunctiva of 78 SWs and 32 RTs were collected before (T1) and immediately after (T2) a 6-month harvest period. The neutral, acid and total mucus content of goblet cells was determined by PAS and AB staining. The levels of MUC5AC, MUC1 and MUC16 mRNA in the conjunctiva were measured by real-time PCR. Compared to RTs, SWs had higher levels of bulbar acid mucus and MUC16 mRNA and tarsal MUC5AC mRNA at T2 and lower levels of neutral mucus at T1 and T2. In the SW group, MUC1 mRNA levels were higher at T2 than at T1, but the levels of neutral and acid mucus were similar. In the RT group, acid mucus decreased and neutral mucus increased in the bulbar and tarsal conjunctiva at T2. In conclusion, our findings show that sugarcane harvesting is associated with abnormalities in mucus quality and content and changes in mucin mRNA levels on the ocular surface. This may help explain the ocular inflammatory signs and symptoms observed in subjects exposed to air pollutants and high temperatures from sugarcane biomass burning.
蔗田燃烧前会产生大量空气污染物，已知这些污染物会导致健康问题，包括眼表异常。在这项研究中，我们评估了生物质燃烧对蔗农（SWs）和毗邻城镇居民（RTs）眼结合膜黏液质量和粘蛋白基因表达（MUC1、MUC5AC、MUC16）的影响。采集 78 名 SWs 和 32 名 RTs 的下穹隆和球结膜印迹细胞学样本，分别在收获前（T1）和收获后（T2）立即采集。通过 PAS 和 AB 染色确定杯状细胞的中性、酸性和总黏液含量。通过实时 PCR 测量结膜中 MUC5AC、MUC1 和 MUC16mRNA 的水平。与 RTs 相比，SWs 在 T2 时具有更高的球结膜酸性黏液和 MUC16mRNA 水平以及 Tarsal MUC5ACmRNA 水平，而在 T1 和 T2 时具有更低的中性黏液水平。在 SW 组中，MUC1mRNA 水平在 T2 时高于 T1，但中性和酸性黏液水平相似。在 RT 组中，T2 时球结膜和穹隆结膜的酸性黏液减少，中性黏液增加。总之，我们的研究结果表明，甘蔗收获与眼表面黏液质量和含量的异常以及粘蛋白 mRNA 水平的变化有关。这可能有助于解释接触蔗田生物质燃烧产生的空气污染物和高温的人群中观察到的眼部炎症体征和症状。
