scholarly journals Insights into Host–Pathogen Interactions in Biofilm-Infected Wounds Reveal Possibilities for New Treatment Strategies

Antibiotics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 396
Author(s):  
Hannah Trøstrup ◽  
Anne Sofie Boe Laulund ◽  
Claus Moser

Normal wound healing occurs in three phases—the inflammatory, the proliferative, and the remodeling phase. Chronic wounds are, for unknown reasons, arrested in the inflammatory phase. Bacterial biofilms may cause chronicity by arresting healing in the inflammatory state by mechanisms not fully understood. Pseudomonas aeruginosa, a common wound pathogen with remarkable abilities in avoiding host defense and developing microbial resistance by biofilm formation, is detrimental to wound healing in clinical studies. The host response towards P. aeruginosa biofilm-infection in chronic wounds and impact on wound healing is discussed and compared to our own results in a chronic murine wound model. The impact of P. aeruginosa biofilms can be described by determining alterations in the inflammatory response, growth factor profile, and count of leukocytes in blood. P. aeruginosa biofilms are capable of reducing the host response to the infection, despite a continuously sustained inflammatory reaction and resulting local tissue damage. A recent observation of in vivo synergism between immunomodulatory and antimicrobial S100A8/A9 and ciprofloxacin suggests its possible future therapeutic potential.

2015 ◽  
Vol 1723 ◽  
Author(s):  
Liam O’Neill ◽  
Barry Twomey ◽  
Peter Dobbyn ◽  
John O’Donoghue

ABSTRACTBiomolecules have been traditionally immobilised onto surfaces using wet chemical techniques for various medical applications. Recent decades have seen plasma methods being used to prepare these surfaces through various forms of surface modification, but the direct exposure of biomolecules to plasma has been avoided due to fears that the molecules would be denatured by the energetic plasma species. Recent results are now demonstrating that direct plasma deposition of biomolecule coatings can be achieved. This creates the possibility to directly modify the surface of implants without any form of surface pre-treatment and this opens up the possibility to alter the healing processes. Materials such as collagen, chitosan, catalase and heparin can be effectively deposited onto surfaces with minimal impact on biological performance and without any chemical binders, linkers or impurities. The performance of these materials has been characterised using both in vitro and in vivo methodologies. In a further step, the results of a preclinical trial are presented which reveal that direct deposition of biomolecules onto open wounds can also be achieved and the impact of this on wound healing is measured in an immunocompromised animal model. A non-thermal plasma device was used to deliver collagen on to chronic wounds and the treatment was shown to promote wound closure in a rabbit wound healing model.


Author(s):  
Heba A.S. El-Nashar ◽  
Shaza H. Aly ◽  
Amirhossein Ahmadi ◽  
Mohamed El-Shazly

Background: Breast cancer is the most frequently diagnosed type of cancer in women (2.1 million) and stands as the fifth leading cause of death. Several treatment strategies are available such as surgical resection, radiation, hormonal therapy, and conventional chemotherapy that are associated with severe adverse effects on the patients. Objective: This review aims to summarize the different studies (in vitro, in vivo, and new patents) concerning the therapeutic potential of plant polyphenolics in the management of breast cancer published in the period from January 2016 to January 2021. Moreover, this review will focus on the underlying mechanism of action and molecular characteristics of these compounds. Methods: The data of this review were collected from different scientific databases such as PubMed, Science Direct, Google Scholarship, sci-finder, and Egyptian Knowledge bank (EKB). Results: During the last period (2016-2021), the in vitro studies investigated about 52 natural compounds of polyphenolic nature with promising anti-breast cancer, while fourteen compounds were reported via in vivo studies. Besides, there were about fifteen compounds registered as patent drugs. Different mechanisms of action and molecular targets were reported to provide a great clarified base and precise reflection for the anticancer properties of these compounds against breast cancer. Conclusion: Polyphenolics represent a plentiful sources of anticancer lead compounds that stand against the progression of breast cancer invasion and metastasis.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Keizo Kohno ◽  
Satomi Koya-Miyata ◽  
Akira Harashima ◽  
Takahiko Tsukuda ◽  
Masataka Katakami ◽  
...  

Abstract Background NK-4 has been used to promote wound healing since the early-1950s; however, the mechanism of action of NK-4 is unknown. In this study, we examined whether NK-4 exerts a regulatory effect on macrophages, which play multiple roles during wound healing from the initial inflammatory phase until the tissue regeneration phase. Results NK-4 treatment of THP-1 macrophages induced morphological features characteristic of classically-activated M1 macrophages, an inflammatory cytokine profile, and increased expression of the M1 macrophage-associated molecules CD38 and CD86. Interestingly, NK-4 augmented TNF-α production by THP-1 macrophages in combination with LPS, Pam3CSK4, or poly(I:C). Furthermore, NK-4 treatment enhanced THP-1 macrophage phagocytosis of latex beads. These results indicate that NK-4 drives macrophage polarization toward an inflammatory M1-like phenotype with increased phagocytic activity. Efferocytosis is a crucial event for resolution of the inflammatory phase in wound healing. NK-4-treated THP-1 macrophages co-cultured with apoptotic Jurkat E6.1 (Apo-J) cells switched from an M1-like phenotype to an M2-like phenotype, as seen in the inverted ratio of TNF-α to IL-10 produced in response to LPS. We identified two separate mechanisms that are involved in this phenotypic switch. First, recognition of phosphatidylserine molecules on Apo-J cells by THP-1 macrophages downregulates TNF-α production. Second, phagocytosis of Apo-J cells by THP-1 macrophages and activation of PI3K/Akt signaling pathway upregulates IL-10 production. Conclusion It is postulated that the phenotypic switch from a proinflammatory M1-like phenotype to an anti-inflammatory M2-like phenotype is dysregulated due to impaired efferocytosis of apoptotic neutrophils at the wound site. Our results demonstrate that NK-4 improves phagocytosis of apoptotic cells, suggesting its potential as a therapeutic strategy to resolve sustained inflammation in chronic wounds.


Membranes ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 702
Author(s):  
Seyyed-Mojtaba Mousavi ◽  
Zohre Mousavi Nejad ◽  
Seyyed Alireza Hashemi ◽  
Marjan Salari ◽  
Ahmad Gholami ◽  
...  

Despite the advances that have been achieved in developing wound dressings to date, wound healing still remains a challenge in the healthcare system. None of the wound dressings currently used clinically can mimic all the properties of normal and healthy skin. Electrospinning has gained remarkable attention in wound healing applications because of its excellent ability to form nanostructures similar to natural extracellular matrix (ECM). Electrospun dressing accelerates the wound healing process by transferring drugs or active agents to the wound site sooner. This review provides a concise overview of the recent developments in bioactive electrospun dressings, which are effective in treating acute and chronic wounds and can successfully heal the wound. We also discuss bioactive agents used to incorporate electrospun wound dressings to improve their therapeutic potential in wound healing. In addition, here we present commercial dressings loaded with bioactive agents with a comparison between their features and capabilities. Furthermore, we discuss challenges and promises and offer suggestions for future research on bioactive agent-loaded nanofiber membranes to guide future researchers in designing more effective dressing for wound healing and skin regeneration.


2021 ◽  
Vol 28 (1) ◽  
Author(s):  
Guzide Bender ◽  
Rezan Fahrioglu Yamaci ◽  
Bahar Taneri

AbstractCRISPR (clustered regularly interspaced short palindromic repeats) systems are one of the most fascinating tools of the current era in molecular biotechnology. With the ease that they provide in genome editing, CRISPR systems generate broad opportunities for targeting mutations. Specifically in recent years, disease-causing mutations targeted by the CRISPR systems have been of main research interest; particularly for those diseases where there is no current cure, including cancer. KRAS mutations remain untargetable in cancer. Mutations in this oncogene are main drivers in common cancers, including lung, colorectal and pancreatic cancers, which are severe causes of public health burden and mortality worldwide, with no cure at hand. CRISPR systems provide an opportunity for targeting cancer causing mutations. In this review, we highlight the work published on CRISPR applications targeting KRAS mutations directly, as well as CRISPR applications targeting mutations in KRAS-related molecules. In specific, we focus on lung, colorectal and pancreatic cancers. To date, the limited literature on CRISPR applications targeting KRAS, reflect promising results. Namely, direct targeting of mutant KRAS variants using various CRISPR systems resulted in significant decrease in cell viability and proliferation in vitro, as well as tumor growth inhibition in vivo. In addition, the effect of mutant KRAS knockdown, via CRISPR, has been observed to exert regulatory effects on the downstream molecules including PI3K, ERK, Akt, Stat3, and c-myc. Molecules in the KRAS pathway have been subjected to CRISPR applications more often than KRAS itself. The aim of using CRISPR systems in these studies was mainly to analyze the therapeutic potential of possible downstream and upstream effectors of KRAS, as well as to discover further potential molecules. Although there have been molecules identified to have such potential in treatment of KRAS-driven cancers, a substantial amount of effort is still needed to establish treatment strategies based on these discoveries. We conclude that, at this point in time, despite being such a powerful directed genome editing tool, CRISPR remains to be underutilized for targeting KRAS mutations in cancer. Efforts channelled in this direction, might pave the way in solving the long-standing challenge of targeting the KRAS mutations in cancers.


Author(s):  
Ghazal Shabestani Monfared ◽  
Peter Ertl ◽  
Mario Rothbauer

Cutaneous wound healing is a complex multi-stage process involving direct and indirect cell communication events with the aim of efficiently restoring the barrier function of the skin. One key aspect in cutaneous wound healing is associated with cell movement and migration into the physically, chemically and biologically injured area resulting in wound closure. Understanding the conditions under which cell migration is impaired and elucidating the cellular and molecular mechanisms that improve healing dynamics is therefore crucial in devising novel therapeutic strategies to elevate patient suffering, reduce scaring and eliminate chronic wounds. Following the global trend towards automation, miniaturization and integration of cell-based assays into microphysiological systems, conventional wound healing assays such as the scratch assay or cell exclusion assay have recently been translated and improved using microfluidics and lab-on-a-chip technologies. These miniaturized cell analysis systems allow precise spatial and temporal control over a range of dynamic microenvironmental factors including shear stress, biochemical and oxygen gradients to create more reliable in vitro models that resemble the in vivo microenvironment of a wound more closely on a molecular, cellular, and tissue level. The current review provides (a) an overview on the main molecular and cellular processes that take place during wound healing, (b) a brief introduction into conventional in vitro wound healing assays, and (c) a perspective on future cutaneous and vascular wound healing research using microfluidic technology.


2020 ◽  
Vol 8 ◽  
Author(s):  
Pengcheng Xu ◽  
Yaguang Wu ◽  
Lina Zhou ◽  
Zengjun Yang ◽  
Xiaorong Zhang ◽  
...  

Abstract Background Autologous platelet-rich plasma (PRP) has been suggested to be effective for wound healing. However, evidence for its use in patients with acute and chronic wounds remains insufficient. The aims of this study were to comprehensively examine the effectiveness, synergy and possible mechanism of PRP-mediated improvement of acute skin wound repair. Methods Full-thickness wounds were made on the back of C57/BL6 mice. PRP or saline solution as a control was administered to the wound area. Wound healing rate, local inflammation, angiogenesis, re-epithelialization and collagen deposition were measured at days 3, 5, 7 and 14 after skin injury. The biological character of epidermal stem cells (ESCs), which reflect the potential for re-epithelialization, was further evaluated in vitro and in vivo. Results PRP strongly improved skin wound healing, which was associated with regulation of local inflammation, enhancement of angiogenesis and re-epithelialization. PRP treatment significantly reduced the production of inflammatory cytokines interleukin-17A and interleukin-1β. An increase in the local vessel intensity and enhancement of re-epithelialization were also observed in animals with PRP administration and were associated with enhanced secretion of growth factors such as vascular endothelial growth factor and insulin-like growth factor-1. Moreover, PRP treatment ameliorated the survival and activated the migration and proliferation of primary cultured ESCs, and these effects were accompanied by the differentiation of ESCs into adult cells following the changes of CD49f and keratin 10 and keratin 14. Conclusion PRP improved skin wound healing by modulating inflammation and increasing angiogenesis and re-epithelialization. However, the underlying regulatory mechanism needs to be investigated in the future. Our data provide a preliminary theoretical foundation for the clinical administration of PRP in wound healing and skin regeneration.


2020 ◽  
Vol 19 (4) ◽  
pp. 598-602
Author(s):  
Malik Asif Hussain ◽  
Flavia Huygens

Chronic wounds, particularly infected wounds are clinically very important due to their significant impact on health budgets as well as patients` health worldwide. Patients with diabetes mellitus, vascular diseases especially peripheral vascular disease and pressure ulcers are major categories of patients presenting with chronic wounds. It is known that there are multiple factors determining chronic wound prognosis. The presence of multiple types of pathogenic bacteria, with specific virulence and adherent (biofilm) properties, contribute a significant role to the development of chronic wounds. This review article is based on the research project entitled” An investigation of the impact of bacterial diversity, pathogenic determinants and biofilms on chronic wounds”. The research findings have been published in form of research papers as well as conference posters. The aim of this article is to highlight various important aspects of bacterial impact on wound healing. Bangladesh Journal of Medical Science Vol.19(4) 2020 p.598-602


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3401
Author(s):  
David Meléndez-Martínez ◽  
Luis Fernando Plenge-Tellechea ◽  
Ana Gatica-Colima ◽  
Martha Sandra Cruz-Pérez ◽  
José Manuel Aguilar-Yáñez ◽  
...  

Chronic wounds are a major health problem that cause millions of dollars in expenses every year. Among all the treatments used, active wound treatments such as enzymatic treatments represent a cheaper and specific option with a fast growth category in the market. In particular, bacterial and plant proteases have been employed due to their homology to human proteases, which drive the normal wound healing process. However, the use of these proteases has demonstrated results with low reproducibility. Therefore, alternative sources of proteases such as snake venom have been proposed. Here, we performed a functional mining of proteases from rattlesnakes (Crotalus ornatus, C. molossus nigrescens, C. scutulatus, and C. atrox) due to their high protease predominance and similarity to native proteases. To characterize Crotalus spp. Proteases, we performed different protease assays to measure and confirm the presence of metalloproteases and serine proteases, such as the universal protease assay and zymography, using several substrates such as gelatin, casein, hemoglobin, L-TAME, fibrinogen, and fibrin. We found that all our venom extracts degraded casein, gelatin, L-TAME, fibrinogen, and fibrin, but not hemoglobin. Crotalus ornatus and C. m. nigrescens extracts were the most proteolytic venoms among the samples. Particularly, C. ornatus predominantly possessed low molecular weight proteases (P-I metalloproteases). Our results demonstrated the presence of metalloproteases capable of degrading gelatin (a collagen derivative) and fibrin clots, whereas serine proteases were capable of degrading fibrinogen-generating fibrin clots, mimicking thrombin activity. Moreover, we demonstrated that Crotalus spp. are a valuable source of proteases that can aid chronic wound-healing treatments.


2019 ◽  
Vol 18 (2) ◽  
pp. 171-175 ◽  
Author(s):  
Pooja Gupta ◽  
Hari Shankar Singh ◽  
Vijay K. Shukla ◽  
Gopal Nath ◽  
Satyanam Kumar Bhartiya

Background: A chronic wound usually results due to halt in the inflammatory phase of wound healing. Bacterial infections and biofilm formation are considered to be the basic cause of it. Chronic wounds significantly impair the quality of life. Antibiotics are now failing due to biofilm formation emergence of drug-resistant bacteria. Objective: This study aims to see the effect of bacteriophage therapy in chronic nonhealing wound infected with the following bacteria: Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Subject: Patients with chronic nonhealing wound not responding to conventional local debridement and antibiotic therapy were included in the study. The age of patients ranged between 12 and 60 years. Method: A total of 20 patients selected and tissue biopsies and wound swabs were taken for isolation of the bacteria. After confirmation of organism, a cocktail of customized bacteriophages was topically applied over the wound on alternate days till the wound surface became microbiologically sterile. Mean bacterial count and clinical assessment were done and compared at the time of presentation and after 3 and 5 doses of application. Results: A significant improvement was observed in the wound healing, and there were no signs of infection clinically and microbiologically after 3 to 5 doses of topical bacteriophage therapy. Seven patients achieved complete healing on day21 during follow up while in others healthy margins and healthy granulation tissue were observed. Conclusion: Topical bacteriophage application may be quite effective therapy for the treatment of chronic nonhealing wounds.


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