Modulation of rifampicin-induced hepatotoxicity using poly(lactic-co-glycolic acid) nanoparticles: a study on rat and cell culture models

In silico drug design strategies for discovering novel tuberculosis therapeutics

INTRODUCTION

Tuberculosis remains a significant concern in global public health due to its intricate biology and propensity for developing antibiotic resistance. Discovering new drugs is a protracted and expensive endeavor, often spanning over a decade and incurring costs in the billions. However, computer-aided drug design (CADD) has surfaced as a nimbler and more cost-effective alternative. CADD tools enable us to decipher the interactions between therapeutic targets and novel drugs, making them invaluable in the quest for new tuberculosis treatments.

AREAS COVERED

In this review, the authors explore recent advancements in tuberculosis drug discovery enabled by in silico tools. The main objectives of this review article are to highlight emerging drug candidates identified through in silico methods and to provide an update on the therapeutic targets associated with Mycobacterium tuberculosis.

EXPERT OPINION

These in silico methods have not only streamlined the drug discovery process but also opened up new horizons for finding novel drug candidates and repositioning existing ones. The continued advancements in these fields hold great promise for more efficient, ethical, and successful drug development in the future.

Nanotechnology-Based Strategies to Combat Multidrug-Resistant Candida auris Infections

An emerging multidrug-resistant pathogenic yeast called Candida auris has a high potential to spread quickly among hospitalized patients and immunodeficient patients causing nosocomial outbreaks. It has the potential to cause pandemic outbreaks in about 45 nations with high mortality rates. Additionally, the fungus has become resistant to decontamination techniques and can survive for weeks in a hospital environment. Nanoparticles might be a good substitute to treat illnesses brought on by this newly discovered pathogen. Nanoparticles have become a trend and hot topic in recent years to combat this fatal fungus. This review gives a general insight into the epidemiology of C. auris and infection. It discusses the current conventional therapy and mechanism of resistance development. Furthermore, it focuses on nanoparticles, their different types, and up-to-date trials to evaluate the promising efficacy of nanoparticles with respect to C. auris.

A Review on Recent Advances in Mannose-Functionalized Targeted Nanocarrier Delivery Systems in Cancer and Infective Therapeutics

Unmodified nanocarriers used in the chemotherapy of cancers and various infectious diseases exhibit prolonged blood circulation time, prevent enzymatic degradation and increase chemical stability of encapsulated therapeutics. However, off-target effect and lack of specificity associated with unmodified nanoparticles (NPs) limit their applications in the health care system. Mannose (Man) receptors with significant overexpression on antigen-presenting cells and macrophages are among the most admired targets for cancer and anti-infective therapeutics. Therefore, development of Man functionalized nanocarriers targeting Man receptors, for target specific drug delivery in the chemotherapy have been extensively studied. Present review expounds diverse Man-conjugated NPs with their potential for targeted drug delivery, improved biodistribution profiles and localization. Additionally, the review gives detailed account of the interactions of mannosylated NPs with various biological systems and their characterization not discussed in earlier published reports is discussed.

Ahmed E, Battah B, Abd Ellah NH, Zanetti S, Donadu MG. Nanotechnology as a Promising Approach to Combat Multidrug Resistant Bacteria: A Comprehensive Review and Future Perspectives

The wide spread of antibiotic resistance has been alarming in recent years and poses a serious global hazard to public health as it leads to millions of deaths all over the world. The wide spread of resistance and sharing resistance genes between different types of bacteria led to emergence of multidrug resistant (MDR) microorganisms. This problem is exacerbated when microorganisms create biofilms, which can boost bacterial resistance by up to 1000-fold and increase the emergence of MDR infections. The absence of novel and potent antimicrobial compounds is linked to the rise of multidrug resistance. This has sparked international efforts to develop new and improved antimicrobial agents as well as innovative and efficient techniques for antibiotic administration and targeting. There is an evolution in nanotechnology in recent years in treatment and prevention of the biofilm formation and MDR infection. The development of nanomaterial-based therapeutics, which could overcome current pathways linked to acquired drug resistance, is a hopeful strategy for treating difficult-to-treat bacterial infections. Additionally, nanoparticles' distinct size and physical characteristics enable them to target biofilms and treat resistant pathogens. This review highlights the current advances in nanotechnology to combat MDR and biofilm infection. In addition, it provides insight on development and mechanisms of antibiotic resistance, spread of MDR and XDR infection, and development of nanoparticles and mechanisms of their antibacterial activity. Moreover, this review considers the difference between free antibiotics and nanoantibiotics, and the synergistic effect of nanoantibiotics to combat planktonic bacteria, intracellular bacteria and biofilm. Finally, we will discuss the strength and limitations of the application of nanotechnology against bacterial infection and future perspectives.

Antileishmanial Agents Co-loaded in Transfersomes with Enhanced Macrophage Uptake and Reduced Toxicity

The prime objective of this study was to develop amphotericin B (AMB) and rifampicin (RIF) co-loaded transfersomal gel (AMB-RIF co-loaded TFG) for effective treatment of cutaneous leishmaniasis (CL). AMB-RIF co-loaded TF was prepared by the thin-film hydration method and was optimized based on particle size, polydispersity index (PDI), zeta potential, entrapment efficiency (%EE), and deformability index. Similarly, AMB-RIF co-loaded TFG was characterized in terms of rheology, spread ability, and pH. In vitro, ex vivo, and in vivo assays were performed to evaluate AMB-RIF co-loaded TF as a potential treatment option for CL. The optimized formulation had vesicles in nanosize range (167 nm) with suitable PDI (0.106), zeta potential (- 19.05 mV), and excellent %EE of RIF (66%) and AMB (85%). Moreover, it had appropriate deformability index (0.952). Additionally, AMB-RIF co-loaded TFG demonstrated suitable rheological behavior for topical application. AMB-RIF co-loaded TF and AMB-RIF co-loaded TFG showed sustained release of the incorporated drugs as compared to AMB-RIF suspension. Furthermore, RIF permeation from AMB-RIF co-loaded TF and AMB-RIF co-loaded TFG was enhanced fivefold and threefold, whereas AMB permeation was enhanced by eightfold and 6.6-fold, respectively. The significantly different IC₅₀, higher CC₅₀, and FIC₅₀ (p < 0.5) showed synergistic antileishmanial potential of AMB-RIF co-loaded TF. Likewise, reduced lesion size and parasitic burden in AMB-RIF co-loaded TF-treated mouse group further established the antileishmanial effect of the optimized formulation. Besides, AMB-RIF co-loaded TFG showed a better safety profile. This study concluded that TFG may be a suitable carrier for co-delivery of AMB-RIF when administered topically for the treatment of CL.

Antibacterial and wound-healing potential of PLGA/spidroin nanoparticles: a study on earthworms as a human skin model

Aim: The essential protein element of spider silk ‘spidroin’ was used to assess its impact on the wound-healing process. Methods: Spidroin nanoparticles (NPs) were prepared using poly(lactic-co-glycolic acid) polymer (PLGA/spidroin NPs) at different weight ratios (5:1, 10:1, 15:1) and were in vitro characterized. The optimized NPs were tested in vitro for release and antibacterial activity. To assess wound-healing effects, NPs were topically applied on surgically induced injuries in Allolobophora caliginosa earthworms as a robust human skin model. Results: Optimized NPs (173 ± 3 nm) revealed considerable antibacterial effect against Staphylococcus aureus and Escherichia coli. After 4 days of NPs application on wounds, macroscopical and histological examinations revealed a significant reduction in wound and re-epithelialization times. Conclusion: PLGA/spidroin NPs may represent a promising option for wound repair.

Antibiofilm and antivirulence potential of silver nanoparticles against multidrug-resistant Acinetobacter baumannii

We aimed to isolate Acinetobacter baumannii (A. baumannii) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy. A. baumannii (n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE and traT) were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of A. baumannii with human fibroblast skin cell line HFF-1 or Vero cell lines. A. baumannii had high level of resistance to antibiotics. Most of the isolates harbored the fimH, afa/draBC, cnf1, csgA and cnf2, and the majority of A. baumannii produced strong biofilms. AgNPs inhibited the growth of A. baumannii efficiently with MIC ranging from 4 to 25 µg/ml. A. baumannii showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of kpsMII , afa/draBC,bap, OmpA, and csuA/B genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular A. baumannii. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.

Studies on the safety and the tissue distribution of inhaled high-dose amorphous and crystalline rifampicin in a rat model

Inhaled delivery of rifampicin has the potential to achieve high drug concentrations in the lung and the blood for efficient treatment of tuberculosis (TB). Due to its existence as polymorphs, in vivo evaluation of the respiratory tract safety of inhalable amorphous and crystalline rifampicin particles, at clinically relevant high-dose, is necessary. This study investigates the lung and liver safety and the tissue distribution of rifampicin after intra-tracheal administration of high (≥25 mg/kg) doses of amorphous and crystalline powder formulations to Sprague Dawley rats. Powder formulations were administered by intra-tracheal insufflation to rats. Lung and liver safety were evaluated by histopathology. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) assays were performed to study the hepatic effects. Rifampicin was quantified in the tissues using LC-MS/MS. Intra-tracheal administration of rifampicin decreased the drug burden on the liver compared to oral administration based on its lower serum ALT activity. Repeated-dose intra-tracheal rifampicin was well tolerated by rats, confirmed by the absence of drug or delivery induced complexities. The histopathological evaluation of rat lungs, after both single and repeated drug administration for seven days, suggested the absence of drug-induced toxicity. Following single intra-tracheal delivery of 50 mg/kg doses, comparable rifampicin concentrations to that from same oral dose were observed in lung, liver, heart and brain. Inhaled delivery of high-dose rifampicin was safe to rat lungs and liver suggesting its potential for localized as well as systemic drug delivery without toxicity concerns.

Appraisal of amiodarone-loaded PLGA nanoparticles for prospective safety and toxicity in a rat model

AIMS

Amiodarone (AM) is a highly efficient drug for arrhythmias treatment, but its extra-cardiac adverse effects offset its therapeutic efficacy. Nanoparticles (NPs)-based delivery system could provide a strategy to allow sustained delivery of AM to the myocardium and reduction of adverse effects. The primary purpose was to develop AM-loaded NPs and explore their ameliorative effects versus off-target toxicities.

MATERIALS AND METHODS

Polymeric NPs were prepared using poly lactic-co-glycolic acid and their physicochemical properties were characterized. Animal studies were conducted using a rat model to compare exposure to AM versus that of the AM-loaded NPs. Biochemical evaluation of liver enzymes, lipid profile, and thyroid hormones was achieved. Besides, histopathological changes in liver and lung were studied.

KEY FINDINGS

Under optimal experimental conditions, the AM-loaded NPs had a size of 186.90 nm and a negative zeta potential (-14.67 mV). Biochemical evaluation of AM-treated animal group showed a significant increase in cholesterol, TG, LDL, T4, and TSH levels (ρ < 0.05). Remarkably, the AM-treated group exhibited a significant increase of liver enzymes (ρ < 0.05) coupled with an obvious change in liver architecture. The AM-loaded NPs displayed a reduction of liver damage and enzyme levels. Lung sections of the AM-treated group demonstrated thickening of interalveolar septa, mononuclear cellular infiltration with congested blood vessels, and heavy collagenous fibers deposition. Conversely, less cellular infiltration and septal thickening were observed in the animal lungs treated with the AM-loaded NPs-treated.

SIGNIFICANCE

Our findings demonstrate the competence of the AM-loaded NPs to open several exciting avenues for evading the AM-induced off-target toxicities.

Engineered photo-chemical therapeutic nanocomposites provide effective antibiofilm and microbicidal activities against bacterial infections in porous devices

Today, prosthetic joint infection (PJI) is still a relatively rare but devastating complication following total hip and/or knee arthroplasty. The treatment of PJI is difficult due to a number of obstacles, such as microbial drug resistance, biofilm protection, and insufficient immune activity, which dramatically diminish the cure rate of PJI to <50%. To efficiently eradicate the bacteria hiding in the implant, photo-chemical joint antibacterial therapeutics based on indocyanine green (ICG) and rifampicin (RIF) co-loaded PLGA nanoparticles (IRPNPs) were developed in this study. The IRPNPs were first characterized as a spherical nanostructure with a size of 266 ± 18.2 nm and a surface charge of -28 ± 1.6 mV. In comparison with freely dissolved ICG, the IRPNPs may confer enhanced thermal stability to the encapsulated ICG and are able to provide a comparable hyperthermic effect and increased production of singlet oxygen under 808 nm near infrared (NIR) exposure with an intensity of 6 W cm-2. Based on the spectrophotometric analysis, the IRPNPs with ≥20-/3.52 μM ICG/RIF were able to provide remarkable antibiofilm and antimicrobial effects against bacteria in a porous silicon bead upon NIR exposure in vitro. Through the analysis of the microbial population index in an animal study, ≥70% Staphylococcus capitis subsp. urealyticus grown in a porous silicon bead in vivo can be successfully eliminated without organ damage or inflammatory lesions around the implant by using IRPNPs + NIR irradiation every 72 h for 9 days. The resulting bactericidal efficacy was approximately three-fold higher than that resulting from using an equal amount of free RIF alone. Taken together, we anticipate that IRPNP-mediated photochemotherapy can serve as a feasible antibacterial approach for PJI treatment in the clinic.

Formulation and in vivo efficacy study of cetuximab decorated targeted bioadhesive nanomedicine for non-small-cell lung cancer therapy

Aim: To design, optimize and evaluate docetaxel-loaded chitosan nanoparticles with (targeted) and without (nontargeted) cetuximab conjugation for the treatment of non-small-cell lung cancer (NSCLC). Materials & methods: Risk-assessment, optimization, in vitro characterizations, stability assessments, release studies, cell-culture studies were performed along with histopathology, pharmacokinetic and anticancer efficacy studies. Results: The nanoparticles of desired particle size (152.59 ± 3.90 nm to 180.63 ± 5.21 nm) which could sustain drug release for up to 70 h, were obtained. The cell-culture studies demonstrated the superiority of the formulations over Docel™. The pharmacokinetic evaluation showed the excellent systemic bioavailability of prepared NPs. The histopathology screening revealed lesser toxicity of both the nontargeted and targeted formulations. The targeted nanoformulation significantly reduced tumor growth than the nontargeted formulation and Docel. Conclusion: These results demonstrate the therapeutic potential of the prepared nanoformulation. After proper clinical validation, it could be a promising approach for the treatment of NSCLC.