Département de Pharmacognosie, Laboratoire PEIRENE - EA 7500, Université de Limoges, Limoges, France.
Laboratoire PEIRENE - EA 7500, Université de Limoges, Limoges, France.
J Appl Microbiol. 2019 Apr;126(4):1044-1058. doi: 10.1111/jam.14188. Epub 2019 Jan 30.
The objective of this study was to explore the diversity of endolichenic fungi from Nephroma laevigatum and to investigate their antiproliferative and antibiofilm potential.
Forty-six isolates were obtained and identified by DNA barcoding. They belonged to genera Nemania, Daldinia, Peziza and Coniochaeta. Six strains belonging to the most represented species were selected and tested for their antiproliferative and antibiofilm activities. Extracts were analysed by reversed-phase HPLC. Activities against fungal and bacterial biofilm were evaluated using tetrazolium salt (XTT) assay and crystal violet assay respectively. Antiproliferative responses of extracts were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis induction by two extracts was observed in two cell lines (HT-29 and PC-3) via morphological changes, pro-apoptotic and anti-apoptotic proteins analysis (Western blotting) and DNA fragmentation. Four extracts displayed activities against Candida albicans biofilm with IC values ranging from 25 to 200 μg ml . All extracts were inactive against Staphylococcus aureus and Pseudomonas aeruginosa biofilms. The most active isolates against human colorectal (HT-29 and HCT116) and prostate (PC-3 and DU145) cancer cell lines were Nemania serpens (NL08) and Nemania aenea var. aureolatum (NL38) with IC values ranging from 13 to 39 μg ml . These extracts induced an apoptotic process through activation of caspases 8 and 3, poly(ADP-ribose) polymerase cleavage and DNA fragmentation.
Selected crude fungal extracts have antiproliferative and antibiofilm activities. Data suggest that this antipoliferative effect is due to apoptosis process. This is the first report showing the effects of endolichenic fungi from N. laevigatum.
This study highlights the therapeutic potential of endolichenic fungi metabolites as sources for drug discovery programmes.
本研究旨在探索地衣内生真菌的多样性，并研究其抗增殖和抗生物膜的潜力。
通过 DNA 条形码获得并鉴定了 46 个分离株。它们属于 Nemania、Daldinia、Peziza 和 Coniochaeta 属。选择了六个属于代表性最强的物种的菌株，并测试了它们的抗增殖和抗生物膜活性。提取物通过反相高效液相色谱法进行分析。使用四唑盐（XTT）测定法和结晶紫测定法分别评估了对真菌和细菌生物膜的活性。通过 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴化物（MTT）测定法测定了提取物的抗增殖反应。通过形态变化、促凋亡和抗凋亡蛋白分析（Western blotting）和 DNA 片段化观察到两种提取物在两种细胞系（HT-29 和 PC-3）中诱导细胞凋亡。四种提取物对白色念珠菌生物膜具有活性，IC 值范围为 25 至 200μg/ml。所有提取物对金黄色葡萄球菌和铜绿假单胞菌生物膜均无活性。对人结直肠（HT-29 和 HCT116）和前列腺（PC-3 和 DU145）癌细胞系最具活性的分离株是 Nemania serpens（NL08）和 Nemania aenea var. aureolatum（NL38），IC 值范围为 13 至 39μg/ml。这些提取物通过激活半胱天冬酶 8 和 3、多聚（ADP-核糖）聚合酶裂解和 DNA 片段化诱导细胞凋亡过程。
选择的粗真菌提取物具有抗增殖和抗生物膜活性。数据表明，这种抗增殖作用是由于细胞凋亡过程。这是首次报道地衣内生真菌对 N. laevigatum 的影响。
本研究强调了地衣内生真菌代谢物作为药物发现计划的潜在治疗价值。
