Assessing the Efficacy of PLGA-Loaded Antimicrobial Peptide OH-CATH30 Microspheres for the Treatment of Bacterial Keratitis: A Promising Approach

Progress in the classification, optimization, activity, and application of antimicrobial peptides

Antimicrobial peptides (AMPs) come from various sources and exhibit unique antimicrobial properties. Their rapid action, effectiveness, and resistance to resistance development make them promising alternatives to combat antibiotic resistance. In addition to its excellent antibacterial properties, AMPs have superior immunomodulatory, antitumor, and antiviral activities. In recent years, the demand for AMPs has continued to increase in many fields, especially in the medical field, and the prospects are extensive. However, AMPs have the disadvantages of expensive development cost, higher hemolysis, short half-life, susceptibility to degradation by protein hydrolases, low bioavailability, toxic side effects, and other disadvantages, which seriously limit the wide application of AMPs. Therefore, fewer AMPs have been approved for marketing or are undergoing clinical trials. The review covers the period from 2001 to 2025 and provides a detailed discussion by searching databases such as Google Scholar and Web of Science. This paper reviews the progress of research on AMPs sources, structures, optimization strategies, biological activities, mechanisms of action, and applications. In general, the development approaches and the number of new AMPs have increased significantly. The improvement technologies for AMPs high hemolysis, poor stability, low bioavailability and high cost have increased significantly. The development cost of AMPs is still high, but many AMPs have been widely used in clinical, food, livestock, poultry, cosmetics and other fields. This article focuses on the commonly used optimization strategies and main activities of AMPs, aiming to effectively respond to challenges and provide a theoretical basis for expanding their application range.

Unlocking the Potential of Antimicrobial Peptides: Cutting-Edge Advances and Therapeutic Potential in Combating Bacterial Keratitis

Bacterial keratitis is a prevalent, and severe corneal illness resulting from bacterial pathogens. Failure to administer a timely and suitable therapy may lead to corneal opacity, ulceration, significant vision impairment, or potential blindness. Current clinical interventions for bacterial keratitis involve the administration of topical antimicrobial agents and systemic antibiotics. However, the misuse and overuse of antibiotics have led to the rapid emergence of antibiotic-resistant bacteria. Additionally, the restricted antibacterial spectrum and possible adverse effects of antibiotics have provided considerable obstacles to traditional therapies. This highlights the urgent need for novel and highly effective antimicrobial agents. Antimicrobial peptides (AMPs) are a class of naturally occurring or synthetically designed small molecules that have gained significant attention due to their unique antimicrobial mechanisms and low risk of resistance development. AMPs exhibit promising potential in treating bacterial keratitis through direct antibacterial mechanisms, such as inhibiting cell wall synthesis, disrupting cell membranes, and interfering with nucleic acid metabolism, as well as indirect mechanisms, including modulation of the host immune response. This review provides a comprehensive overview of the antibacterial mechanisms of AMPs and their advancements in the treatment of bacterial keratitis. It emphasizes the role of various modification strategies and artificial-intelligence-assisted design in enhancing the antibacterial efficacy, stability, and biocompatibility of AMPs. Furthermore, this review discusses the latest progress in combining AMPs with delivery systems for improved therapeutic outcomes. Finally, the review highlights the current challenges and future perspectives of AMPs in bacterial keratitis treatment, providing valuable insights for developing novel AMPs with high antibacterial efficacy, stability, and safety for bacterial keratitis therapies.

Recent Advances in Peptide-Loaded PLGA Nanocarriers for Drug Delivery and Regenerative Medicine

Peptide-loaded poly(lactide-co-glycolide) (PLGA) nanocarriers represent a transformative approach to addressing the challenges of peptide-based therapies. These systems offer solutions to peptide instability, enzymatic degradation, and limited bioavailability by providing controlled release, targeted delivery, and improved stability. The versatility of PLGA nanocarriers extends across therapeutic domains, including cancer therapy, neurodegenerative diseases, vaccine development, and regenerative medicine. Innovations in polymer chemistry, surface functionalization, and advanced manufacturing techniques, such as microfluidics and electrospraying, have further enhanced the efficacy and scalability of these systems. This review highlights the key physicochemical properties, preparation strategies, and proven benefits of peptide-loaded PLGA systems, emphasizing their role in sustained drug release, immune activation, and tissue regeneration. Despite remarkable progress, challenges such as production scalability, cost, and regulatory hurdles remain.

Recombinant Antimicrobial Peptides (rAMPs); Potential Applications in Medicine and Veterinary Medicine: A Review

Antibiotic resistance has become a major public health concern worldwide. Treatment of humans and animals is becoming increasingly challenging due to antibiotic resistance. Antibiotic-resistant bacteria can be transmitted from animals to humans by several routes, including direct contact, contaminated food or water, or environmental exposure. Various factors contribute to the rising problem, such as the widespread and indiscriminate exploitation of antimicrobials in both human and animal healthcare, over-prescription, misuse of antibiotics, the role of agriculture in spreading antibiotic resistance, and poor animal husbandry practices. According to the preliminary findings, recombinant antimicrobial peptides are an interesting novel area of biotechnology and medical innovation that might be employed as a secure and effective substitute for antibiotics. In this review study, we briefly examine the factors contributing to the rise of antibiotic resistance. We then introduce and discuss recombinant antimicrobial peptides as a promising strategy to address this growing problem.

Exploring PLGA-OH-CATH30 Microspheres for Oral Therapy of Escherichia coli-Induced Enteritis

Antibiotic therapy effectively addresses Escherichia coli-induced enteric diseases, but its excessive utilization results in microbial imbalance and heightened resistance. This study evaluates the therapeutic efficacy of orally administered poly (lactic-co-glycolic acid) (PLGA)-loaded antimicrobial peptide OH-CATH30 microspheres in murine bacterial enteritis. Mice were categorized into the healthy control group (CG), untreated model group (MG), OH-CATH30 treatment group (OC), PLGA-OH-CATH30 treatment group (POC), and gentamicin sulfate treatment group (GS). Except for the control group, all other experimental groups underwent Escherichia coli-induced enteritis, followed by a 5-day treatment period. The evaluation encompassed clinical symptoms, intestinal morphology, blood parameters, inflammatory response, and gut microbiota. PLGA-OH-CATH30 microspheres significantly alleviated weight loss and intestinal damage while also reducing the infection-induced increase in spleen index. Furthermore, these microspheres normalized white blood cell count and neutrophil ratio, suppressed inflammatory factors (IL-1β, IL-6, and TNF-α), and elevated the anti-inflammatory factor IL-10. Analysis of 16S rRNA sequencing results demonstrated that microsphere treatment increased the abundance of beneficial bacteria, including Phocaeicola vulgatus, in the intestinal tract while concurrently decreasing the abundance of pathogenic bacteria, such as Escherichia. In conclusion, PLGA-OH-CATH30 microspheres have the potential to ameliorate intestinal damage and modulate the intestinal microbiota, making them a promising alternative to antibiotics for treating enteric diseases induced by Escherichia coli.