Topical Treatment of Second-Degree Burn Wounds with Lactobacillus plantarum Supernatant: Phase I Trial

Targeting Microbial Biofilms and Promoting Wound Healing in MRSA-Infected Diabetic Rats using Postbiotics of Lactiplantibacillus plantarum

Recalcitrant wounds in diabetic patients are difficult to treat and often require debridement and surgical intervention. Methicillin-resistant Staphylococcus aureus (MRSA), a common pathogen isolated from the diabetic wounds, further delays healing. This study investigates the wound-healing properties of the postbiotics of Lactiplantibacillus plantarum 2034 in MRSA-infected diabetic rats. Ethyl acetate extract (EAE) of L. plantarum was prepared, and its antimicrobial and antibiofilm properties against various pathogens were determined. EAE exhibited broad spectrum antimicrobial activity against various Gram-positive and Gram-negative bacterial pathogens including MRSA. At sub-MIC concentration, EAE inhibited biofilm formation by various pathogens, resulting in maximum inhibition of 82.6% for Bacillus subtilis, 73% for MRSA, and 43% for Salmonella typhi. At MBC concentration, EAE successfully disrupted preformed biofilms of the pathogens, probably due to interference with quorum sensing as shown by its ability to inhibit violacein pigment production by a biosensor Chromobacterium violaceum CV026. Carbopol 934 gel of EAE was formulated and applied to MRSA-infected wounds in diabetic rats. EAE gel showed significant (P < 0.05) reduction in the counts of MRSA on day 4 and complete clearance by day 12. EAE-treated wounds showed significantly (P < 0.05) faster wound closure rate compared to the untreated and standard drug-treated wounds. Histological analysis showed restoration of normal architecture of skin in EAE-treated wounds compared to the untreated and standard drug-treated groups. Furthermore, EAE treatment normalised the mRNA expression of proinflammatory cytokine interleukin (IL)-6 and doubled the levels of anti-inflammatory cytokine IL-10 compared to the untreated control. In conclusion, the dual antimicrobial and anti-inflammatory properties of the EAE gel make it a strong candidate for treating chronic MRSA-infected diabetic wounds. Gas chromatography-mass spectrometry analysis of EAE revealed the presence of several antimicrobial and antioxidant compounds.

The relationship between the skin microbiome and probiotics in the healing of burn injuries

The relationship between the skin microbiome and probiotics in the healing of burn injuries has garnered significant attention in recent years. Burn injuries disrupt the delicate balance of the skin microbiome, leading to complications in the healing process. Probiotic therapies have emerged as promising interventions to restore microbial balance, inhibit biofilm formation, and accelerate tissue repair. Probiotics may also mitigate the risk of antibiotic-resistant infections, which is a major concern in burn units. By enhancing immune responses and stimulating the production of antimicrobial peptides, probiotics can effectively combat bacterial colonization and prevent the emergence of drug-resistant strains. A combination of probiotics with other therapies, such as phages or nanoparticles, holds significant promise for enhancing burn healing. This approach can effectively treat burn wounds by promoting wound healing synergy, preventing infection, modulating the immune response, and disrupting biofilms. Overall, the relationship between the skin microbiome and probiotics in burn wound healing has substantial potential to advance the field of burn wound management.

Probiotic, Postbiotic, and Paraprobiotic Effects of Lactobacillus rhamnosus as a Modulator of Obesity-Associated Factors

Obesity is a pandemic currently affecting the world's population that decreases the quality of life and promotes the development of chronic non-communicable diseases. Lactobacillus rhamnosus is recognized for multiple positive effects on obesity and overall health. In fact, such effects may occur even when the microorganisms do not remain alive (paraprobiotic effects). This raises the need to elucidate the mechanisms by which obesity-associated factors can be modulated. This narrative review explores recent findings on the effects of L. rhamnosus, particularly, its postbiotic and paraprobiotic effects, on the modulation of adiposity, weight gain, oxidative stress, inflammation, adipokines, satiety, and maintenance of intestinal integrity, with the aim of providing a better understanding of its mechanisms of action in order to contribute to streamlining its clinical and therapeutic applications. The literature shows that L. rhamnosus can modulate obesity-associated factors when analyzed in vitro and in vivo. Moreover, its postbiotic and paraprobiotic effects may be comparable to the more studied probiotic actions. Some mechanisms involve regulation of gene expression, intracellular signaling, and enteroendocrine communication, among others. We conclude that the evidence is promising, although there are still multiple knowledge gaps that require further study in order to fully utilize L. rhamnosus to improve human health.

Occurrence and distribution of antibiotic resistance genes in Rivers entering the sea from the South bank of Laizhou Bay, China

The distribution of antibiotic resistance genes (ARGs) in Laizhou Bay affects the local socio-economic development. The study aimed to investigate the distribution of ARGs in the rivers that flow into the sea around Laizhou Bay's southern shore. Water and sediment samples were collected from different typical sites of rivers entering the sea in Weifang, including Mi River, Bai Lang River, Yu River, Wei River, Jiaolai River, Xiaoqing River and Di River. The species and abundance of ARGs in the sediments were characterized and quantified by macro-genome high-throughput sequencing technology. The species distribution of ARGs was compared. In two sediment samples and seven water samples, 24 ARGs types and 1244 subtypes of ARGs were detected, in which multidrug-resistant class was the main ARGs type and FBJ murine osteosarcoma viral oncogene homolog B (fosB) was the dominant ARGs. The types of ARG in the top ten of these samples were the same, although the proportion was different. Dominant ARG subtypes accounted for more than 50% of all the nine samples. This article provides basic data support for pollution status and environmental risk assessment as well as remediation of ARGs in rivers entering the sea along the south coast of Laizhou Bay.

Topical Probiotic Hydrogels for Burn Wound Healing

Hydrogels have increasingly been used to enhance the effective healing of various wounds, including burn wounds. Similarly, the application of probiotics has recently been explored in wound healing and skin repairs. While probiotics have been consumed to provide therapeutic effects that aid with improving gut health, topical applications have been found to accelerate wound healing both in vitro and in vivo. For wounds that have complex healing mechanisms, such as burn wounds which depend on factors such as the depth of the burn, size of the afflicted area, and cause of the injury, probiotics with or without conventional therapeutic agents topically delivered via hydrogel technology are proven to be effective in the recovery of the damaged skin. This article aims to investigate the microorganisms present in the human skin microbiome and observe the effects of probiotics delivered by hydrogels on burn wound healing.

Natural Guardians: Natural Compounds as Radioprotectors in Cancer Therapy

Cancer remains a significant global health challenge, with millions of deaths attributed to it annually. Radiotherapy, a cornerstone in cancer treatment, aims to destroy cancer cells while minimizing harm to healthy tissues. However, the harmful effects of irradiation on normal cells present a formidable obstacle. To mitigate these effects, researchers have explored using radioprotectors and mitigators, including natural compounds derived from secondary plant metabolites. This review outlines the diverse classes of natural compounds, elucidating their roles as protectants of healthy cells. Furthermore, the review highlights the potential of these compounds as radioprotective agents capable of enhancing the body's resilience to radiation therapy. By integrating natural radioprotectors into cancer treatment regimens, clinicians may improve therapeutic outcomes while minimizing the adverse effects on healthy tissues. Ongoing research in this area holds promise for developing complementary strategies to optimize radiotherapy efficacy and enhance patient quality of life.

Strong Activity and No Resistance Induction Exerted by Cell-Free Supernatants from Lacticaseibacillus rhamnosus against Mono-Species and Dual-Species Biofilms of Wound Pathogens in In Vivo-like Conditions

It is widely agreed that microbial biofilms play a major role in promoting infection and delaying healing of chronic wounds. In the era of microbial resistance, probiotic strains or their metabolic products are emerging as an innovative approach for the treatment of hard-to-heal (chronic) wounds due to their antimicrobial, healing, and host immune-modulatory effects. In this study, we aimed to investigate the potential of cell-free supernatants (CFS) from Lacticaseibacillus rhamnosus GG against mono- and dual-species biofilms of wound pathogens in a 3D in vitro infection model. Mature biofilms of Pseudomonas aeruginosa and Staphylococcus aureus were obtained on collagen scaffolds in the presence of a simulant wound fluid (SWF) and treated with CFS at different doses and time intervals. At 1:4 dilution in SWF, CFS caused a marked reduction in the colony forming-unit (CFU) numbers of bacteria embedded in mono-species biofilms as well as bacteria released by the biofilms in the supernatant. CFU count and electron microscopy imaging also demonstrated a marked antibiofilm effect against dual-species biofilms starting from 8 h of incubation. Furthermore, CFS exhibited acceptable levels of cytotoxicity at 24 h of incubation against HaCaT cells and, differently from ciprofloxacin, failed to induce resistance after 15 passages at sub-inhibitory concentrations. Overall, the results obtained point to L. rhamnosus GG postbiotics as a promising strategy for the treatment of wound biofilms.

Antibacterial Activity and Toxicity of Zinc Oxide Nanoparticles Combined with Supernatants of Lactobacillus spp. Against ESKAPE Bacteria: A Novel Mixture

Background

The emergence of multidrug resistance among nosocomial pathogens has prompted researchers to look for new antibacterial sources. Metal nanoparticles and probiotic products have attracted the attention of researchers. However, combination therapy is an attractive alternative in this field.

Objectives

This study evaluated the antibacterial activity and toxicity of Zinc Oxide nanoparticles (ZnO-NPs) combined with cell-free supernatant (CFS) of Lactobacillus plantarum and Lactobacillus acidophilus alone and in a novel mixture.

Methods

Antibacterial effects and cytotoxic properties of ZnO-NPs, CFS of L. plantarum (SLP), and CFS of L. acidophilus (SLA) were determined alone and in a mixture against ESKAPE strains. In addition, the viability percentage of the cells was evaluated after exposure to these agents.

Results

Antibacterial mixtures (ZnO-NPs with SLP or ZnO-NPs with SLA) demonstrated synergistic and additive effects against Pseudomonas aeruginosa (FIC≤0.75), Acinetobacter baumannii (FIC = 1), and Escherichia coli (FIC≤0.75). The viability percentage of the cells after 24 h of exposure to a mixture of ZnO-NPs and SLA (about 50%) was more than when the cells were exposed to ZnO-NPs alone (about 30%) at the same concentration.

Conclusions

A mixture of ZnO-NPs and CFS of probiotics can be an alternative to antibiotics, with more effectiveness and fewer side effects.