Recent Advances in Anti-Infective Drug Discovery - Volume 20, Issue 1, 2025

Recent research has been concentrated on investigating the involvement of Toxoplasma gondii (T. gondii) in the progression of liver disorders. This study aims to investigate the prevalence of T. gondii infection in patients with non-alcoholic fatty liver disease (NAFLD), as well as the effects of toxoplasmosis infection on biological biomarkers such as aspirate transaminase (AST), alanine transaminase (ALT), cholesterol (Chol), and triglyceride (Tg) levels in Sistan, southeast Iran.

A case-control study was conducted between December 2021 and September 2022. The study included 225 patients diagnosed with NAFLD as the case group and 225 healthy blood donors as the control group. The controls were selected from the same region and were matched with the patients based on gender and age. We collected serum samples from all patients and utilized an enzyme-linked immunosorbent assay to analyze them for the existence of anti-T. gondii IgG antibodies. A questionnaire and medical records were utilized to gather data on the patient's demographic factors.

The prevalence of anti-T. gondii IgG antibodies were 68 (30.2%) in patients with NAFLD, whereas it was 11 (4.88%) in the control group. The seroprevalence of T. gondii in NAFLD patients increased in correlation with age (P < 0.001). The prevalence of NAFLD was significantly greater in the seropositive group compared to the seronegative group (P < 0.001). In addition, the levels of the metabolic markers Chol and Tg were significantly higher in T. gondii seropositive NAFLD patients compared to T. gondii seronegative NAFLD patients.

The findings of this study indicate a high seroprevalence of T. gondii in patients with NAFLD. Further studies are warranted to investigate the underlying mechanisms and potential therapeutic implications of this association.

The emergence of resistance to multiple drugs has posed a multitude of difficulties that demand immediate attention and solutions. Multiple drug resistance arises from the accumulation of numerous genes within a single cell, each conferring resistance to a specific drug, and from the heightened expression of genes responsible for multidrug efflux pumps. These pumps effectively expel a diverse array of drugs from the cell.

The multi-drug-resistant organisms, including methicillin-resistant Staphylococcus aureus, are the hub of numerous diseases, from minute ailments to fatal diseases, like catheter infections. Nowadays, a combination of many antibiotics is given together as a multimodality therapy to cure MRSA infections. However, researchers are exploring novel approaches to find better solutions.

De novo designing of the peptide sequences has been done through an in silico tool. The peptides were further screened using different computational methods. Following this, the selection was conducted utilizing physicochemical properties as criteria. Molecular docking of the selected peptide sequence was carried out. Based on the highest docking score, the model complex was chosen for validation purposes by conducting studies through molecular dynamics simulations.

A total of fifty-two novel antimicrobial peptides were designed and evaluated based on various parameters, targeting MRSA-specific proteins PBP2a and PVL toxin. Among these designed peptides, the peptide sequence VILRMFYHWAVKTNGP emerged as the optimal candidate, satisfying all the necessary parameters to be an effective antimicrobial peptide.

Molecular docking and MD simulation results showed that the designed peptide sequence could be the possible solution for MRSA treatment.

The aim of this study was to investigate the antimicrobial photodynamic, sonodynamic, and combined photodynamic and sonodynamic potentials of IR780 iodide loaded mesoporous silica nanoparticles against gram-negative Pseudomonas aeruginosa (P. aeruginosa) and multi drug resistant Pseudomonas aeruginosa (MDR P. aeruginosa).

IR780 iodide loaded mesoporous silica nanoparticles were synthesized, and their antimicrobial photodynamic and sonodynamic potentials against one P. aeruginosa strain, and one MDR P. aeruginosa strain were investigated. Laser irradiation was achieved via a 785 nm diode laser (500 mW/cm², 5 min). Ultrasound irradiation was achieved via a 1-MHz ultrasound unit (1.5 W/cm², 50% duty cycle, 3 min). Viable bacterial cells were counted by serial dilution method. Data were analyzed by ANOVA followed by Tukey's test (p ≤ 0.05).

The results revealed that for P. aeruginosa, the combined photodynamic therapy (PDT) and sonodynamic therapy (SDT) showed a 44% reduction in bacterial cell viability as compared to 18% and 31% when exposed to SDT alone and PDT alone, respectively. For MDR. P. aeruginosa, the combined treatment resulted in a 45% reduction in bacterial cell viability, as compared to 14% and 30% when exposed to SDT alone and PDT alone, respectively. The killing effect was mainly due to the photodynamic and sonodynamic effects of the nanoparticles, mainly caused by singlet oxygen. No photothermal effect was involved in the killing.

The results of this study demonstrated that IR780 iodide-loaded mesoporous silica nanoparticles have the potential to be utilized as photo/sono therapeutic agents for the inactivation of drug-resistant bacteria.