Insight Into the Beneficial Role of Lactiplantibacillus plantarum Supernatant Against Bacterial Infections, Oxidative Stress, and Wound Healing in A549 Cells and BALB/c Mice

Ashish Kumar Dubey,Mansi Podia,Sanpreet Singh,Neeraj Khatri,Priyanka Priyanka,Anil Kumar Pinnaka,Sachin Raut

doi:10.3389/fphar.2021.728614

Abstract

Lactiplantibacillus plantarum MTCC 2621 is a well-characterized probiotic strain and is reported to possess many health benefits. However, the wound healing potential of this probiotic is yet to be explored. Here, we have assessed the antibacterial, antioxidant, and wound healing activities of cell-free supernatant of Lactiplantibacillus plantarum MTCC 2621 (Lp2621). Lp2621 exhibited excellent antibacterial activity against the indicator bacteria in the agar well diffusion assay. Lp2621 did not show any hemolytic activity. The safety of Lp2621 gel was established using the skin irritation assay in BALB/c mice, and no dermal reactions were observed. The supernatant showed 60–100% protection of A549 cells against H2O2-induced stress. In the scratch assay, Lp2621 accelerated wound healing after 24 h of treatment. The percent wound healing was significantly higher in cells treated with Lp2621 at 18–24 h posttreatment. In an excision wound healing in mice, topical application of Lp2621 gel showed faster healing than the vehicle- and betadine-treated groups. Similar wound healing activity was observed in wounds infected with Staphylococcus aureus. Histological examination revealed better wound healing in Lp2621-treated mice. Topical treatment of the wounds with Lp2621 gel resulted in the upregulation of pro-inflammatory cytokine IL-6 in the early phase of wound healing and enhanced IL-10 expression in the later phase. These findings unveil a protective role of Lp2621 against bacterial infection, oxidative stress, and wound healing.

Highlights

Wound healing is a multifaceted biological process involving many extracellular and intracellular macromolecules
The treatment of A549 cells with different concentrations (6.25 and 12.5%) of Lactiplantibacillus plantarum Microbial Type Culture Collection (MTCC) 2621 (Lp2621) results in faster wound healing than the positive control after 24 h of treatment (Figure 3)
Another group demonstrated that the topical application of live L. reuteri DSM 17938 and its lysate induced anti-inflammatory activity by reducing the levels of proinflammatory cytokines (IL-6 and IL-8) (Khmaladze et al, 2019)

Summary

Introduction

Wound healing is a multifaceted biological process involving many extracellular and intracellular macromolecules. Probiotics lower the risk of infectious diseases, and in combination with antibiotics, combat secondary infections (King et al, 2014) as well as reduce the incidence and severity of diarrhea associated with antibiotic therapy (Hempel et al, 2012) They primarily belong to the genus Lactobacillus and Bifidobacterium (Soccol et al, 2010), and effectively modulate the immune function of the host by maintaining the balance of the intestinal microbiota (Ouwehand et al, 2016), improve the innate immunity, and moderate the functions of dendritic cells, macrophages, and T and B lymphocytes (Georgieva et al, 2015). In this study, we assessed the antibacterial, antioxidant, and wound healing properties of the cell-free supernatant of Lpb. plantarum MTCC 2621 ( read as Lp2621) using A549 cells in vitro and in a mouse model of wound healing

Methods

Results

Conclusion