Tyrosol-gold nanoparticle functionalized acacia gum-PVA nanofibers for mitigation of Candida biofilm.

Increasing incidences of fungal infections and prevailing antifungal resistance in healthcare settings has given rise to an antifungal crisis on a global scale. The members of the genus Candida, owing to their ability to acquire sessile growth, are primarily associated with superficial to invasive fungal infections, including the implant-associated infections. The present study introduces a novel approach to combat the sessile/biofilm growth of Candida by fabricating nanofibers using a nanoencapsulation approach. This technique involves the synthesis of tyrosol (TYS) functionalized chitosan gold nanocomposite, which is then encapsulated into PVA/AG polymeric matrix using electrospinning. The FESEM, FTIR analysis of prepared TYS-AuNP@PVA/AG NF suggested the successful encapsulation of TYS into the nanofibers. Further, the sustained and long-term stability of TYS in the medium was confirmed by drug release and storage stability studies. The prepared nanomats can absorb the fluid, as evidenced by the swelling index of the nanofibers. The growth and biofilm inhibition, as well as the disintegration studies against Candida, showed 60-70 % biofilm disintegration when 10 mg of TYS-AuNP@PVA/AG NF was used, hence confirming its biological effectiveness. Subsequently, the nanofibers considerably reduced the hydrophobicity index and ergosterol content of the treated cells. Considering the challenges associated with the inhibition/disruption of fungal biofilm, the fabricated nanofibers prove their effectiveness against Candida biofilm. Therefore, nanocomposite-loaded nanofibers have emerged as potential materials that can control fungal colonization and could also promote healing.

Tuning foreign body response with tailor-engineered nanoscale surface modifications: fundamentals to clinical applications.

Biomaterials are omnipresent in today's healthcare services and are employed in various applications, including implants, sensors, healthcare accessories, and drug delivery systems. Unfavorable host immunological responses frequently jeopardize the efficacy of biomaterials. As a result, surface modification has received much attention in controlling inflammatory responses since it helps camouflage the biomaterial from the host immune system, influencing the foreign body response (FBR) from protein adsorption to fibrous capsule formation. Surfaces with controlled nanotopography and chemistry, among other surface modification methodologies, have effectively altered the immune response to biomaterials. However, the field is still in its early stages, with only a few studies showing a synergistic effect of surface chemistry and nanotopography on inflammatory and wound healing pathways. Therefore, this review will concentrate on the individual and synergistic effects of surface chemistry and nanotopography on FBR modulation and the molecular processes known to modulate these responses. This review will also provide insights into crucial research gaps and advancements in various tactics for modulating FBR, opening new paths for future research. This will further aid in improving our understanding of the immune response to biomaterials, developing advanced surface modification techniques, designing immunomodulatory biomaterials, and translating discoveries into clinical applications.

Detailed investigation of catalytically important residues of class A ß-lactamase.

An increasing global health challenge is antimicrobial resistance. Bacterial infections are often treated by using ß-lactam antibiotics. But several resistance mechanisms have evolved in clinically mutated bacteria, which results in resistance against such antibiotics. Among which production of novel ß-lactamase is the major one. This results in bacterial resistance against penicillin, cephalosporin, and carbapenems, which are considered to be the last resort of antibacterial treatment. Hence, ß-lactamase enzymes produced by such bacteria are called extended-spectrum ß-lactamase and carbapenemase enzymes. Further, these bacteria have developed resistance against many ß-lactamase inhibitors as well. So, investigation of important residues that play an important role in altering and expanding the spectrum activity of these ß-lactamase enzymes becomes necessary. This review aims to gather knowledge about the role of residues and their mutations in class A ß-lactamase, which could be responsible for ß-lactamase mediated resistance. Class A ß-lactamase enzymes contain most of the clinically significant and expanded spectrum of ß-lactamase enzymes. Ser70, Lys73, Ser130, Glu166, and Asn170 residues are mostly conserved and have a role in the enzyme's catalytic activity. In-depth investigation of 69, 130, 131, 132, 164, 165, 166, 170, 171, 173, 176, 178, 179, 182, 237, 244, 275 and 276 residues were done along with its kinetic analysis for knowing its significance. Further, detailed information from many previous studies was gathered to know the effect of mutations on the kinetic activity of class A ß-lactamase enzymes with ß-lactam antibiotics.Communicated by Ramaswamy H. Sarma.

Insights into structure and activity relationship of clinically mutated PER1 and PER2 class A ß-lactamase enzymes.

PER1 and PER2 are among the class A ß-lactamase enzymes, which have evolved clinically to form antibiotic resistance and have significantly expanded their spectrum of activity. Hence, there is a need to study the clinical mutation responsible for such ß-lactamase mediated antibiotic resistance. Alterations in catalytic centre and Ω-loop structure could be the cause of antibiotic resistance in these ß-lactamase enzymes. Structural and functional alterations are caused due to mutations on or near the catalytic centre, which results in active site plasticity and are responsible for its expanded spectrum of activity in these class A ß-lactamase enzymes. Multiple sequence alignment, structure, kinetic, molecular docking, MMGBSA and molecular dynamic simulation comparisons were done on 38 clinically mutated and wild class A ß-lactamase enzymes. This work shows that PER1 and PER2 enzymes contains most unique mutations and have altered Ω-loop structure, which could be responsible for altering the structure-activity relationship and extending the spectrum of activity of these enzymes. Alterations in molecular docking, MMGBSA, kinetic values reveals the modification in the binding and activity of these clinically mutated enzymes with antibiotics. Further, the cause of these alterations can be revealed by active site interactions and H-bonding pattern of these enzymes with antibiotics. Met69Gln, Glu104Thr, Tyr105Trp, Met129His, Pro167Ala, Glu168Gln, Asn170His, Ile173Asp and Asp176Gln mutations were uniquely found in PER1 and PER2 enzymes. These mutations occurs at catalytic important residues and results in altered interactions with ß-lactam antibiotics. Hence, these mutations could be responsible for altering the structure-activity of PER1 and PER2 enzymes.Communicated by Ramaswamy H. Sarma.

Plausible Mechanistic Insights in Biofilm Eradication Potential against Candida spp. Using In Situ-Synthesized Tyrosol-Functionalized Chitosan Gold Nanoparticles as a Versatile Antifouling Coating on Implant Surfaces.

In the present study, tyrosol-functionalized chitosan gold nanoparticles (Chi-TY-AuNPs) were prepared as an alternative treatment strategy to combat fungal infections. Various biophysical techniques were used to characterize the synthesized Chi-TY-AuNPs. The antifungal and antibiofilm activities of Chi-TY-AuNPs were evaluated against Candida albicans and C. glabrata, and efforts have been made to elucidate the possible mechanism of action. Chi-TY-AuNPs showed a high fungicidal effect against both sessile and planktonic cells of Candida spp. Additionally, Chi-TY-AuNPs completely eradicated (100%) the mature biofilms of both the Candida spp. FESEM analysis highlighted the morphological alterations in Chi-TY-AuNP-treated Candida biofilm cells. The effect of Chi-TY-AuNPs on the ECM components showed significant reduction in protein content in the C. glabrata biofilm and substantial decrease in extracellular DNA content of both the Candida spp. ROS generation analysis using DCFDA-PI staining showed high ROS levels in both the Candida spp., whereas pronounced ROS production was observed in the Chi-TY-AuNP-treated C. glabrata biofilm. Biochemical analysis revealed decreased ergosterol content in Chi-TY-AuNP-treated C. glabrata cells, while inconsequential changes were observed in C. albican s. Furthermore, the transcriptional expression of selected genes (ergosterol biosynthesis, efflux, sterol importer, and glucan biogenesis) was reduced in C. glabrata in response to Chi-TY-AuNPs except ERG11 and CDR1. Conclusively, the result showed the biofilm inhibition and biofilm eradication efficacy of Chi-TY-AuNPs in both the Candida spp. Findings of the present study manifest Chi-TY-AuNPs as a potential therapeutic solution to Candida biofilm-related chronic infections and overcome biofilm antifungal resistance.

Exploration of interaction mechanism of tyrosol as a potent anti-inflammatory agent.

Drug discovery for a vigorous and feasible lead candidate is a challenging scientific mission as it requires expertise, experience, and huge investment. Natural products and their derivatives having structural diversity are renowned source of therapeutic agents since many years. Tyrosol (a natural phenylethanoid) has been extracted from olive oil, and its structure was confirmed by elemental analysis, FT-IR, FT-NMR, and single crystal X-ray crystallography. The conformational analysis for tyrosol geometry was performed by Gaussian 09 in terms of density functional theory. Validation of bond lengths and bond angles obtained experimentally as well as theoretically were performed with the help of curve fitting analysis, and values of correlation coefficient (R) obtained as 0.988 and 0.984, respectively. The charge transfer within the tyrosol molecule was confirmed by analysis of HOMO→LUMO molecular orbitals. In molecular docking with COX-2 (PDB ID: 5F1A), tyrosol was found to possess satisfactory binding affinity as compared to other NSAIDs (Aspirin, Ibuprofen, and Naproxen) and a COX-2 selective drug (Celecoxib). ADMET prediction, drug-likeness and bioactivity score altogether confirm the lead/drug like potential of tyrosol. Further investigation of simulation quality plot, RMSD and RMSF plots, ligands behavior plot as well as post simulation analysis manifest the consistency of 5F1A-tyrosol complex throughout the 20 ns molecular simulation process that signifies its compactness and stability within the receptor pocket. AbbreviationsADMETAbsorption, Distribution, Metabolism, Excretion and ToxicityÅAngstromCOX-2Cyclooxygenase-2DFTDensity Functional TheoryDMFDimethylformamideFMOFrontier Molecular OrbitalFT-IRFourier-transform Infrared SpectroscopyFT-NMRNuclear Magnetic Resonance SpectroscopyHOMOHighest Occupied Molecular OrbitalLUMOLowest Unoccupied Molecular OrbitalMDMolecular DynamicsNSNanosecondNSAIDsNon-steroidal anti-inflammatory drugsOPEOsiris Property ExplorerRMSDRoot-Mean-Square DeviationRMSFRoot Sean Square FluctuationCommunicated by Ramaswamy H. Sarma.

Structure-based drug designing and identification of Woodfordia fruticosa inhibitors targeted against heat shock protein (HSP70-1) as suppressor for Imiquimod-induced psoriasis like skin inflammation in mice model.

Heat shock proteins (HSPs) emerged as a therapeutic target and it was observed that inhibition of HSP70-1 plays a pivotal role in the management of psoriasis. In-silico investigation involving techniques like molecular docking and molecular dynamics (MD) simulation analysis was performed against HSP70-1. Further, anti-psoriatic activity of bioactive immunomodulatory compounds present in ethanolic extract of Woodfordia fruticosa flowers (Wffe) using combination of bioinformatics together with ethnopharmacological approach has been explored in this study. Myricetin (-8.024), Quercetin (-7.368) and Ellagic acid (-7.311) were the top three compounds with minimum energy levels as well as high therapeutic value/ADMET as compared to currently available marketed anti-psoriatic drug Tretinoin (-7.195). ADMET prediction was used to screen ligands for drug-likeness and efficacy. Further, biogenically Woodfordia fruticosa gold nanoparticles (WfAuNPs) were synthesized and characterized by UV-Visible Spectroscopy (UV-vis), Dynamic Light Scattering (DLS), Zeta Potential, X-Ray Diffraction (XRD) and High Resolution Transmission Electron Microscopy (HRTEM) techniques. Synthesized WfAuNPs observed in the size range of 10-20 nm and were used to develop WfAuNPs-Carbopol®934 ointment gel. Subsequently, the therapeutic efficacy of WfAuNPs-Carbopol® 934 was checked against 5% Imiquimod-induced psoriasis like skin inflammation. WfAuNPs-Carbopol® 934 was found to be exerting better therapeutic effect in reducing the mean DAI score (0.63 ±â€¯0.08), serum cytokines (TNF-α, IL-22 and IL-23) levels along with reduced epidermal thickness, parakeratosis and marked decrease in the hyperproliferation of keratinocytes. Results of the study revealed that the WfAuNPs-Carbopol® 934 could be an effective alternative treatment for psoriasis in near future.

Application of Computational Techniques to Unravel Structure-Function Relationship and their Role in Therapeutic Development.

Application of computational tools and techniques has emerged as an invincible instrument to unravel the structure-function relationship and offered better mechanistic insights in the designing and development of new drugs along with the treatment regime. The use of in silico tools equipped modern chemist with armamentarium of extensive methods to meticulously comprehend the structural tenacity of receptor-ligand interactions and their dynamics. In silico methods offers a striking property of being less resource intensive and economically viable as compared to experimental evaluation. These techniques have proved their mettle in the designing of potential lead compounds to combat life-threatening diseases such as AIDS, cancer, tuberculosis, malaria, etc. In the present scenario, computer-aided drug designing has ascertained an essential and indispensable gizmo in therapeutic development. This review will present a brief outline of computational methods used at different facets of drug designing and its latest advancements. The aim of this review article is to briefly highlight the methodologies and techniques used in structure-based/ ligand-based drug designing viz., molecular docking, pharmacophore modeling, density functional theory, protein-hydration and molecular dynamics simulation which helps in better understanding of macromolecular events and complexities.

Synergistic effects of Woodfordia fruticosa gold nanoparticles in preventing microbial adhesion and accelerating wound healing in Wistar albino rats in vivo.

Therapeutic effectiveness of biogenically synthesized Woodfordia fruticosa nano-gold particles (WfAuNPs) has been claimed in this study which prevents microbial adhesion and enhanced wound healing potential on Wistar albino rats. The synthesized WfAuNPs were characterized using several biophysical techniques such as UV-Visible Spectroscopy (UV-vis), X-Ray Diffraction (XRD), Dynamic Light Scattering (DLS), Zeta Potential, Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM) and High Resolution Transmission Electron Microscopy (HR-TEM) analysis. The synthesized WfAuNPs in the size range of 10-20nm were used to develop 1% Carbopol® 934 based nano gold formulation (WfAuNPs-Carbopol® 934). The WfAuNPs-Carbopol® 934 nanoformulation was evaluated using viscosity and spreadability measurements. The wound healing potential of WfAuNPs-Carbopol® 934 monitored up to 12days was confirmed by performing wound contraction (%), epithelialization, and histopathological studies done in vivo on Wistar albino rats. The hydroxyproline content was also measured in the re-epithelized skin for quantification of collagen content. The effects of WfAuNPs on microbial adhesion leading to biofilm formation were evaluated against Candida albicans and Cryptococcus neoformans fungal strains. The respective Minimum Inhibitory Concentration (MIC80), Biofilm Inhibitory Concentration (BIC80) and Biofilm Eradication Concentration (BEC80) values of C. albicans was found to be 16, 32, 256µg/ml respectively while for C. neoformans it was recorded to be 32, 64, 256µg/ml respectively. Data obtained, confirmed the effectiveness in preventing microbial adhesion and wound healing potential of the WfAuNPs as compared to current marketed formulations.