Dey Poulomi, Puppala Eswara Rao, Naidu Vegi Ganga Modi, Das Gopal, Ramesh Aiyagari
Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, India.
Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education and Research Guwahati, Guwahati 781125, India.
ACS Appl Bio Mater. 2020 Dec 21;3(12):8830-8840. doi: 10.1021/acsabm.0c01164. Epub 2020 Nov 30.
The relentless menace of implant- and skin wound-associated infections caused by methicillin-resistant (MRSA) biofilms demands the design of therapeutics that have an edge over conventional antibiotics. The present study reports the potential of pluri-active amphiphiles having a 12-carbon alkyl chain and a salicaldehyde head group (C1) or a napthaldehyde head group (C2) in mitigating wound site- and implant-associated MRSA biofilms and as a topical wound healing agent. The amphiphiles impeded MRSA 100 biofilm formation on collagen both on extraneous addition and on impregnation into collagen and inflicted damage to MRSA cells embedded in collagen matrix infused with simulated wound fluid, with C1 being more potent than C2. Adhesion of the MRSA biofilm was hampered on C1-coated orthopedic stainless-steel wire, while eluates from C1-coated wires were non-toxic to HEK 293 cells, highlighting the prospect of C1 as an implant-associated antibacterial coating. Upon treatment with C1, expression of the adhesin gene was low in the MRSA biofilm and downregulated in non-adherent MRSA cells, while δ-toxin () gene expression in the MRSA biofilm increased, implying that C1 hindered cell-cell adhesion and planktonic-biofilm transition and also reduced biofilm adhesion. Oral administration of C1 (300 and 1000 mg/kg) was non-toxic to BALB/c mice as evidenced in stable hematological parameters and normal histopathological features of vital organs. Topical application of C1 (50 and 100 mg/kg) on a skin excision wound in female BALB/c mice resulted in effective wound closure, fibrous tissue proliferation, and tissue reorganization. Confocal microscopy revealed that topical application of C1 in an murine skin explant could alleviate invasion of skin by MRSA, while solution-based studies indicated subdued MRSA adhesion onto the skin explants. The pluri-active synthetic amphiphile C1 provides a framework for developing antibacterials that hold translational potential as a therapeutic for implant- and skin wound-associated MRSA infections.
耐甲氧西林(MRSA)生物膜引起的植入物和皮肤伤口相关感染的持续威胁,要求设计出比传统抗生素更具优势的治疗方法。本研究报告了具有12碳烷基链和水杨醛头基(C1)或萘醛头基(C2)的多活性两亲物在减轻伤口部位和植入物相关的MRSA生物膜方面的潜力,以及作为局部伤口愈合剂的潜力。两亲物在外部添加和浸渍到胶原蛋白中时,均能阻止MRSA在胶原蛋白上形成生物膜,并对嵌入注入模拟伤口液的胶原蛋白基质中的MRSA细胞造成损伤,其中C1比C2更有效。MRSA生物膜在C1涂层的骨科不锈钢丝上的粘附受到阻碍,而C1涂层钢丝的洗脱液对HEK 293细胞无毒,这突出了C1作为植入物相关抗菌涂层的前景。用C1处理后,MRSA生物膜中粘附素基因的表达较低,在非粘附的MRSA细胞中下调,而MRSA生物膜中δ-毒素()基因的表达增加,这意味着C1阻碍了细胞间粘附和浮游生物-生物膜转变,也降低了生物膜粘附。口服C1(300和1000 mg/kg)对BALB/c小鼠无毒,血液学参数稳定和重要器官组织病理学特征正常证明了这一点。在雌性BALB/c小鼠的皮肤切除伤口上局部应用C1(50和100 mg/kg)可有效促进伤口闭合、纤维组织增生和组织重塑。共聚焦显微镜显示,在小鼠皮肤外植体中局部应用C1可减轻MRSA对皮肤的侵袭,而基于溶液的研究表明MRSA在皮肤外植体上的粘附受到抑制。多活性合成两亲物C1为开发抗菌药物提供了一个框架,这些抗菌药物作为植入物和皮肤伤口相关MRSA感染的治疗方法具有转化潜力。