Andrographolide reduces cisplatin resistance of endometrial cancer Ishikawa/DPP cells by inhibiting the Fas/FasL signaling axis / 中国肿瘤生物治疗杂志

@#目的：探讨穿心莲内酯（Andro）调节脂肪酸合成酶（Fas）/脂肪酸合成酶配体（FasL）信号轴对子宫内膜癌Ishikawa细胞顺铂（DDP）耐药性的影响。方法：采用0、5、10、20 μg/mL DDP分别处理Ishikawa细胞和顺铂耐药的Ishikawa/DPP细胞，0、5、10、25、50 μmol/L Andro处理Ishikawa/DDP细胞，MTT法检测细胞增殖情况并为后续实验选择合适的给药剂量。将Ishikawa/DDP细胞随机分为对照组、DDP组（DDP干预）、Andro组（DDP、Andro干预）、pcDNA3.1-NC组（转染pcDNA3.1+DDP、Andro干预）、pcDNA3.1-Fas/FasL组（转染pcDNA3.1-Fas/FasL+DDP、Andro干预），24 h后，采用qPCR法检测Fas、FasL mRNA的表达，平板克隆形成实验、Transwell实验和流式细胞术分别检测细胞克隆能力、细胞迁移与侵袭和细胞凋亡，WB法检测增殖细胞核抗原（PCNA）、BAX、Bcl-2、MMP-2、PD-L1、多药耐药蛋白-1（MDR-1）及Fas、FasL蛋白表达。结果：DDP以剂量依赖的方式抑制Ishikawa和Ishikawa/DPP细胞增殖，并且与Ishikawa细胞比较，Ishikawa/DPP细胞对DDP的敏感性更低（均P<0.05）；Andro以剂量依赖性的方式抑制Ishikawa/DPP细胞的增殖（均P<0.05）。Ishikawa/DPP细胞中Fas、FasL的表达水平均高于Ishikawa细胞（均P<0.05）。选取20 μg/mL DDP和25 μmol/L Andro为干预剂量，干预时间24 h。与对照组比较，DDP组Ishikawa/DPP细胞中PD-L1、MDR-1、Fas、FasL mRNA及蛋白表达水平显著升高（P<0.05），而克隆形成率、迁移与侵袭细胞数、凋亡率差异均无统计学意义（均P>0.05）；与DDP组比较，Andro组Ishikawa/DPP细胞中Fas、FasL mRNA表达水平、细胞克隆形成率、迁移与侵袭细胞数、PCNA、Bcl-2、MMP-2、PD-L1、MDR-1、Fas、FasL蛋白表达水平显著降低，BAX蛋白表达水平及凋亡率显著升高（P<0.05或P<0.01），pcDNA3.1-NC组与Andro组类似；与pcDNA3.1-NC组比较，pcDNA3.1-Fas/FasL组Ishikawa/DPP细胞上述指标变化均被逆转（P<0.05）。结论：Andro可能通过抑制Fas/FasL信号轴来抑制Ishikawa/DPP细胞增殖、迁移与侵袭，促进凋亡，从而降低细胞对DDP的耐药性。

Uptake, translocation, and metabolism of thiamethoxam in soil by leek plants.

Thiamethoxam (TMX) is commonly applied on leek plants by root irrigation. It might be taken up by leek plants and thus has lasting dietary risk. In this study, the uptake, translocation, and metabolism of TMX in leek plants were investigated. The results obtained from both the hydroponic and soil experiments indicated that TMX could be easily translocated upward and accumulated in leek shoots after being absorbed by roots. The total absorbed TMX amount (Mtotal) in leek plants from the tested soils varied greatly with its adsorption governed by soil characteristics. Interestingly, Mtotal was closely correlated with the concentration of TMX in in situ pore water, indicating that TMX in in situ pore water could be a useful approach to predict uptake of this chemical by leek plants from various soils. Profoundly, clothianidin (CLO) was detected with concentration of 0.07-1.54 mg/kg in roots and 0.27-4.12 mg/kg in shoots at 14 d, respectively, suggesting that TMX is easily converted into CLO in leek plants. The results showed that TMX used in soil is easily absorbed by leek and accumulated in edible parts accompanying with formation of CLO.

Prevalence of Azole-Resistant Aspergillus fumigatus is Highly Associated with Azole Fungicide Residues in the Fields.

Triazole resistance in Aspergillus fumigatus is a growing public health concern. In addition to its emergence in the therapy of invasive aspergillosis by triazole medicines, it has been frequently detected in agricultural fields all over the world. Here, we explore the potential link between residues of azole fungicides with similar chemical structure to triazole medicines in soil and the emergence of resistant A. fumigatus (RAF) through 855 500 km2 monitoring survey in Eastern China covering 6 provinces. In total, 67.3%, 15.2%, 12.3%, 2.9%, 1.5%, 0.4%, and 0.3% of the soil samples contained these five fungicides (tebuconazole, difenoconazole, propiconazole, hexaconazole, and prochloraz) of 0-100, 100-200, 200-400, 400-600, 600-800, 800-1000, and >1000 ng/g, respectively. The fractions of samples containing RAF isolates were 2.4%, 5.2%, 6.4%, 7.7%, 7.4%, 14.3%, and 20.0% of the samples with total azole fungicide residues of 0-100, 100-200, 200-400, 400-600, 600-800, 800-1000, and >1000 ng/g, respectively. We find that the prevalence of RAFs is positively (P < 0.0001) correlated with residual levels of azole fungicides in soils. Our results suggest that the use of azole fungicides in agriculture should be minimized and the intervals between treatments expanded to reduce the selective pressure toward the development of resistance in A. fumigatus in agricultural fields.

Five-Year Survey (2014 to 2018) of Azole Resistance in Environmental Aspergillus fumigatus Isolates from China.

A total of 191 soil samples from Hangzhou, China, were submitted to detect non-wild-type (non-WT) Aspergillus fumigatus and its associated mechanisms. There were 2 (4.7%), 13 (12.4%), and 31 (23.1%) isolates identified as non-WT in 2014, 2016, and 2018, respectively. The resistant mutations of TR34/L98H, TR46/Y121F/T289A, and TR34/L98H/S297T/F495I were found in 3, 5, and 5 non-WT isolates. The G448S mutation, previously only found in clinical settings, was detected in A. fumigatus from soil samples.

Triazole resistance in Aspergillus fumigatus in crop plant soil after tebuconazole applications.

Aspergillus fumigatus is the primary agent of invasive aspergillosis (IA) causing high morbidity and mortality in immunocompromised patients. Triazole resistance in A. fumigatus and its sources have gained wide attention. For several years, environmental fungicides use has been proposed as the major cause for triazole resistance in A. fumigatus. However, there are few studies on azole-resistant A. fumigatus (ARAF) selected by triazole fungicides in agricultural systems. We studied the possible emergence of ARAF in the field after exposure to triazole fungicide tebuconazole. Our results showed that exposure to tebuconazole in soil selects for resistance to triazoles in A. fumigatus. The probability of ARAF developing in soils depends upon the concentrations of tebuconazole after application. We suggest that tebuconazole applications should be minimized to reduce selective pressure for the generation of ARAFs.

Subcellular distribution governing accumulation and translocation of pesticides in wheat (Triticum aestivum L.).

Root uptake, translocation, and subcellular distribution of six pesticides (dinotefuran, thiamethoxam, imidacloprid, imazethapyr, propiconazole, and chlorpyrifos) with Kow ranging from -0.549 to 4.7 were investigated in wheat to study transportation and accumulation of pesticides. The root bioconcentration factor (RCF) of pesticides decreased with water solubility (R2 = 0.6121) and increased with hydrophobicity (when the pH-adjusted log Kow > 2, R2 = 0.925), respectively. The translocation of neutral pesticides from roots to shoots increased positively with water solubility (R2 > 0.6484) but decreased with hydrophobicity (R2 > 0.8039). The subcellular fraction concentration factor (SFCF) increased linearly with hydrophobicity of the tested pesticides (R2 > 0.958). The log RCF was positively correlated with log SFCF in root cell walls (R2 = 0.9894) and organelles (R2 = 0.9786). Transportation of the pesticides from roots to stems and stems to leaves was adversely affected by the log SFCF of cell walls and organelles of roots (R2 > 0.7997) and stems (R2 > 0.6666), respectively. Hydrophobicity-dependent SFCF is a factor governing accumulation of pesticides in roots after uptake and their subsequent upward translocation.

Upward translocation of acetochlor and atrazine in wheat plants depends on their distribution in roots.

Residual acetochlor and atrazine in soils, resulting from their extensive application to maize plants, may affect product safety of the ultimate wheat crop. To determine the potential uptake and accumulation of acetochlor and atrazine by wheat plants, the uptake mechanism, translocation, and subcellular distribution of these two herbicides were studied through hydroponic experiments (10 mg L-1). The results indicated that acetochlor can be taken up through the apoplastic pathway and can accumulate in wheat roots with little upward translocation. However, atrazine could be taken up by roots through the symplastic pathway and subsequently transported to the stems and leaves. Little upward translocation of acetochlor in wheat plants was due to its preferential distribution into root organelles with higher lipid contents. Conversely, the low bioconcentration of atrazine in root organelles and cell walls after uptake led to its easy upward translocation. Uptake of acetochlor and atrazine by wheat roots and the distribution of atrazine to the stems and leaves were predicted well by using the partition-limited model. The obtained results indicated that residual atrazine in soil may be taken up by wheat roots and acropetally translocated, thereby posing a threat to product safety of wheat.

Uptake, Translocation, and Subcellular Distribution of Azoxystrobin in Wheat Plant ( Triticum aestivum L.).

The uptake mechanism, translocation, and subcellular distribution of azoxystrobin (5 mg kg-1) in wheat plants was investigated under laboratory conditions. The wheat-water system reached equilibrium after 96 h. Azoxystrobin concentrations in roots were much higher than those in stems and leaves under different exposure times. Azoxystrobin uptake by roots was highly linear at different exposure concentrations, while the bioconcentration factors and translocation factors were independent of the exposed concentration at the equilibrium state. Dead roots adsorbed a larger amount of azoxystrobin than fresh roots, which was measured at different concentrations. Azoxystrobin preferentially accumulated in organelles, and the highest distribution proportion was detected in the soluble cell fractions. This study elucidated that the passive transport and apoplastic pathway dominated the uptake of azoxystrobin by wheat roots. Azoxystrobin primarily accumulated in roots and could be acropetally translocated, but its translocation capacity from roots to stems was limited. Additionally, the uptake and distribution of azoxystrobin by wheat plants could be predicted well by a partition-limited model.