Pine-derived peptide PN5 kills drug-resistant Salmonella and boosts immune response in mice

PN5, an antimicrobial peptide from pine needles, killed multidrug-resistant Salmonella Typhimurium through membrane disruption and immune modulation, significantly improving survival in a mouse infection model.

Park, Jonggwan et al.·ACS omega·2025·lowAnimal StudyAnimal Study
RPEP-12959Animal Studylow2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
low
Sample
N=Not reported (mouse and cell study)
Participants
Multidrug-resistant Salmonella Typhimurium in vitro and in mouse infection model

What This Study Found

PN5 demonstrated dual-function activity: direct bactericidal membrane disruption against MDR S. Typhimurium plus immune modulation via NF-κB and MAPK pathways. It eliminated intracellular bacteria in macrophages, inhibited biofilm formation, and significantly improved survival in a murine infection model.

Key Numbers

PN5 was stable across diverse pH and temperature conditions. Inhibited biofilm formation. Eliminated intracellular S. Typhimurium in RAW 264.7 macrophages. Modulated NF-kB and MAPK signaling. Improved survival in murine infection model.

How They Did This

In vitro antibacterial assays (MIC, membrane disruption, biofilm inhibition, cytotoxicity), intracellular killing assays in RAW 264.7 macrophages, signaling pathway analysis (NF-κB, MAPK), and in vivo murine S. Typhimurium infection model.

Why This Research Matters

Multidrug-resistant Salmonella is a growing public health threat with limited treatment options. A natural peptide that both kills resistant bacteria directly and helps the immune system clear infection represents a fundamentally different approach than conventional antibiotics.

The Bigger Picture

As antibiotic resistance continues to rise, antimicrobial peptides from natural sources offer alternative strategies. PN5's dual mechanism—directly killing bacteria while modulating host immunity—addresses a key limitation of traditional antibiotics, which only target the pathogen without supporting the immune response.

What This Study Doesn't Tell Us

Derived from a plant source; scalability and cost of production need evaluation. Only tested against S. Typhimurium; activity against other MDR pathogens is unknown. Mouse model results require validation in larger animals and eventually humans. Pharmacokinetic properties not characterized.

Questions This Raises

  • ?Is PN5 effective against other multidrug-resistant bacterial species beyond Salmonella?
  • ?Can PN5 be produced at scale for clinical development, and what are the manufacturing challenges?
  • ?Would PN5 work synergistically with existing antibiotics to overcome resistance?

Trust & Context

Key Stat:
Dual-function antimicrobial PN5 both directly kills MDR Salmonella via membrane disruption and boosts host immune clearance via NF-κB/MAPK modulation
Evidence Grade:
Comprehensive preclinical study with in vitro mechanism of action, intracellular killing demonstration, and in vivo survival benefit. Strong proof of concept but limited to one pathogen species and animal models.
Study Age:
Published in 2025; represents current antimicrobial peptide discovery research.
Original Title:
Peptide PN5 from Pinus densiflora Confers in Vivo Protection Against Multidrug-Resistant Salmonella Typhimurium Through Membrane Disruption.
Published In:
ACS omega, 10(50), 61322-61338 (2025)
Database ID:
RPEP-12959

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

How does PN5 kill drug-resistant bacteria?

PN5 disrupts the outer membrane of bacteria, causing them to lose their structural integrity and die. This mechanism is fundamentally different from conventional antibiotics, making it harder for bacteria to develop resistance. It also works on bacteria hiding inside immune cells.

Why is a peptide from pine needles being studied as a medicine?

Plants produce antimicrobial peptides as part of their natural defense against infections. These peptides have been refined by millions of years of evolution and can have potent activity against human pathogens. PN5 from Korean pine shows particularly promising dual activity—killing bacteria directly while also helping the immune system fight infection.

Read More on RethinkPeptides

Cite This Study

RPEP-12959·https://rethinkpeptides.com/research/RPEP-12959

APA

Park, Jonggwan; Kang, Da Dam; Kim, Hyeongsun; Oh, Jun Hee; Park, Yoonkyung. (2025). Peptide PN5 from Pinus densiflora Confers in Vivo Protection Against Multidrug-Resistant Salmonella Typhimurium Through Membrane Disruption.. ACS omega, 10(50), 61322-61338. https://doi.org/10.1021/acsomega.5c06012

MLA

Park, Jonggwan, et al. "Peptide PN5 from Pinus densiflora Confers in Vivo Protection Against Multidrug-Resistant Salmonella Typhimurium Through Membrane Disruption.." ACS omega, 2025. https://doi.org/10.1021/acsomega.5c06012

RethinkPeptides

RethinkPeptides Research Database. "Peptide PN5 from Pinus densiflora Confers in Vivo Protection..." RPEP-12959. Retrieved from https://rethinkpeptides.com/research/park-2025-peptide-pn5-from-pinus

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.