In this study we have reported an efficient antibacterial hybrid fabricated through surface functionalization of lysozyme capped gold nanoclusters (AUNC-L) with β-lactam antibiotic ampicillin (AUNC-L-Amp). The prepared hybrid not only reverted the MRSA resistance towards ampicillin but also demonstrated enhanced antibacterial activity against non-resistant bacterial strains. Most importantly, upon awakening through cis-2-decenoic acid (cis-DA) exposure, the MRSA persister got inhibited by the AUNC-L-Amp treatment. Intraperitoneal administration of this hybrid eliminates the systemic MRSA infection in a murine animal model. Topical application of this nano conjugate eradicated MRSA infection from difficult to treat diabetic wound of rat and accelerated the healing process. Due to inherent bio-safe nature of gold, AUNC-L alone or in the construct (AUNC-L-Amp) demonstrated excellent biocompatibility and did not indicate any deleterious effects in in vivo settings. We postulate that AUNC-L-Amp overcomes the elevated levels of β-lactamase at the site of MRSA antibiotic interaction with subsequent multivalent binding to the bacterial surface and enhanced permeation. Coordinated action of AUNC-L-Amp components precludes MRSA to attain resistance against the hybrid. We proposed that the inhibitory effect of AUNC-L-Amp against MRSA and its persister form is due to increased Amp concentration at the site of action, multivalent presentation and enhanced permeation of Amp through lysozyme-mediated cell wall lysis.

Poor wound healing is one of the major complication of diabetic patients which arises due to different factors like hyperglycemia, oxidative stress, vascular insufficiency and microbial infections. Candidiasis of diabetic wounds is a difficult to treat condition and potentially can lead to organ amputation. There are a few number of medications available in market to treat this chronic condition; which demands for alternative treatment options. In traditional system of medicine like Ayurveda, essential oil extracted from leaves of Cymbopogon nardus L. (Poaceae) has been using for the treatment of microbial infections, inflammation and pain. In this regard, we have evaluated anti-Candida and anti-inflammatory activity mediated wound healing property of C. nardus essential oil (EO-CN) on candidiasis of diabetic wounds. EO-CN was obtained through hydro-distillation and subjected to Gas chromatography mass spectroscopy (GC-MS) analysis for chemical profiling. Anti-Candida activity of EO-CN was tested against C. albicans, C. glabrata and C. tropicalis by in-vitro zone of inhibition and minimum inhibitory concentration (MIC) assays. Anti-candidiasis ability of EO-CN was evaluated on C. albicans infected diabetic wounds of mice through measuring candida load on the 7th, 14th and 21st day of treatment. Further progression in wound healing was confirmed by measuring the inflammatory marker levels and histopathology of wounded tissues on last day of EO-CN treatment. A total of 95 compounds were identified through GC-MS analysis, with major compounds like citral, 2,6-octadienal- 3,7-dimethyl-, geranyl acetate, citronellal, geraniol and citronellol. In vitro test results demonstrated strong anti-Candida activity of EO-CN with a MIC value of 25 µg/ml against C. albicans, 50 µg/ml against C. glabrata and C. tropicalis. EO-CN treatment resulted in significant reduction of candida load on diabetic wounds. Acceleration in wound healing was indicated by declined levels of inflammatory cytokines at wounded area in EO-CN treated animals compared to non-treated group, which was further confirmed by histopathological examination. This study suggests that through significant anti-Candida and anti-inflammatory activity, EO-CN attenuates the growth of the fungus on diabetic wounds and simultaneously reduces the inflammation which leads to acceleration of the wound healing process.

Methicillin-resistant Staphylococcus aureus (MRSA) and Candida co-infections in the context of burn wounds, leads to morbidity and mortality. Eradication of such difficult to treat complex infection needs concomitant effective topical administration of an antibiotic–antifungal cocktail. Application of the broad-spectrum antibiotic chloramphenicol (CAM) has been hindered owing to its hydrophobicity, poor dermal penetration, rapid degradation and toxicity issues. But, due to its lesser uses in the past, CAM continues to be active against a majority of currently predominant resistant bacterial strains. Additionally, the essential oil of Cymbopogon flexuous possesses strong, broad spectrum antimicrobial property and also acts as a synergistic enhancer when used in combination with antibiotics. But due to its highly volatile nature and instability in free form, topical administration has not been possible. Keeping this in mind, we co-encapsulate CAM with lemongrass essential oil in PCL–Pluronic composite nanocapsules (CAM–LEO–PCL–P NCs) and were successful in overcoming the limitations in drug administration and achieved a significant reduction in cytotoxicity than that of the free counterparts with increased therapeutic index. CAM–LEO–PCL–P NCs exhibited significantly enhanced in vitro antimicrobial activity against 22 microbial pathogens including ten clinical MRSA isolates and three Candida species. This therapeutic nanocapsule was able to penetrate into burn wounds and demonstrated pronounced wound healing ability against MRSA-Candida co-infected burn wounds of mice by significant reduction of the pathogen burden. It also helps in increased cellular proliferation and collagen synthesis in the wounded area with the reduction of inflammatory cytokines. We propose CAM–LEO–PCL–P NCs as a potential candidate to treat chronic wound infections.

In this study, a glycogen–gold nanohybrid was fabricated to enhance the potency of a promising hepatoprotective agent silymarin (Sly) by improving its solubility and gut permeation. By utilizing a facile green chemistry approach, biogenic gold nanoparticles were synthesized from Annona reticulata leaf phytoconstituents in combination with Sly (SGNPs). Further, the SGNPs were aggregated in glycogen biopolymer to yield the therapeutic nanohybrids (GSGNPs). Transmission electron microscopy, UV–Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy analysis confirmed the successful formation and conjugation of both SGNPs and GSGNPs. The fabricated nanohybrids showed significant protection against CCl₄-induced hepatic injury in Wistar rats and maintained natural antioxidant (superoxide dismutase and catalase) levels. Animals treated with GSGNPs (10 mg/kg) and SGNPs (20 mg/kg) retained usual hepatic functions with routine levels of hepatobiliary enzymes (aspartate transferase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase) and inflammatory markers (interleukin-1β and tumor necrosis factor-α) with minimal lipid peroxidation, whereas those treated with 100 mg/kg of Sly showed the similar effect. These results were also supported by histopathology of the livers where pronounced hepatoprotection with normal hepatic physiology and negligible inflammatory infiltrate were observed. Significant higher plasma C_max supported the enhanced bioavailability of Sly upon GSGNPs treatment compared to SGNPs and free Sly. Graphite furnace atomic absorption spectrophotometry analysis also substantiated the efficient delivery of GSGNPs over SGNPs. The fabricated therapeutic nanohybrids were also found to be biocompatible toward human erythrocytes and L929 mouse fibroblast cells. Overall, due to increased solubility, bioavailability and profuse gut absorption; GSGNPs demonstrated tenfold enhanced potency compared to free Sly.

Artesunate (ART), a plant based semi-synthetic antimalarial drug, is emerging as a new class of effective cancer chemotherapeutics. However, the dosage of ART required to have an anti-cancer effect on cancer cells is greater than that needed to exterminate malarial parasites. The goal of this study was to develop an effective combination therapy to reduce the dose-dependent side effects of ART both in vitro and in vivo. In our study, 4-phenylbutyrate (4-PB), a histone deacetylase inhibitor (HDAC), exhibited significant synergistic induction of apoptosis in MCF-7 cells in combination with ART. The IC₅₀ of ART decreased significantly from 55.56 ± 5.21 µM to 24.71 ± 3.44 µM in MCF-7 cells. ART treatment increased cellular oxidative stress, and the resulting generation of intracellular reactive oxygen species (ROS) caused extensive DNA damage in the cell. The extent of ROS production and cell cycle arrest were further enhanced by 4-PB treatment. In further investigation, we found that 4-PB attenuated mRNA expression of crucial DNA damage response (DDR) elements of the nonhomologous end-joining (NHEJ) pathway, consequently enhancing the DNA damaging effect of ART. Furthermore, the combination therapy resulted in improvement in the life expectancy of the treated mice and a prominent reduction in tumour volume without interfering with the normal biochemical, haematological and histological parameters of the mice. Overall, our study revealed a novel combination therapy in which 4-PB potentiated the cytotoxicity of ART synergistically and provided a promising combination drug for effective cancer therapy.