“Methicillin-resistant Staphylococcus aureus (MRSA) is a major human pathogen that causes a wide range of infections. Its resistance to β-lactam antibiotics complicates treatment due to the limited number of antibiotics with activity against MRSA. To investigate development of alternative therapeutics, the mechanisms that mediate antibiotic resistance in MRSA need to be fully understood. In this study, MRSA cells were subjected to antibiotic stress from methicillin in combination with three cannabinoid compounds and analyzed using proteomics to assess the changes in physiology. Subjecting MRSA to nonlethal levels of methicillin resulted in an increased production of penicillin-binding protein 2 (PBP2). Exposure to cannabinoids showed antibiotic activity against MRSA, and differential proteomics revealed reduced levels of proteins involved in the energy production as well as PBP2 when used in combination with methicillin.”
Category Archives: Staphyloccus infections
Antifungal and antibacterial activities of Cannabis sativa L. resins
“Ethnopharmacological relevance: Cannabis sativa L. (Cannabaceae) is a plant native to Eastern Asia spread throughout the world because of its medicinal properties. Despite being used for thousands of years as a palliative therapeutic agent for many pathologies, in many countries research on its effects and properties could only be carried out in recent years, after its legalization.
Aims of the study: Increasing resistance to traditional antimicrobial agents demands finding new strategies to fight against microbial infections in medical therapy and agricultural activities. Upon legalization in many countries, Cannabis sativa is gaining attention as a new source of active components, and the evidence for new applications of these compounds is constantly increasing.
Methods: Extracts from five different varieties ofCannabis sativa were performed and their cannabinoids and terpenes profiles were determined by liquid and gas chromatography. Antimicrobial and antifungal activities against Gram (+) and Gram (-) bacteria, yeast and phytopathogen fungus were measured. To analyze a possible action mechanism, cell viability of bacteria and yeast was assessed by propidium iodide stain.
Results: Cannabis varieties were grouped into chemotype I and II as a consequence of their cannabidiol (CBD) or tetrahydrocannabinol (THC) content. The terpenes profile was different in quantity and quality among varieties, with (-)b-pinene, b-myrcene, p-cymene and b-caryophyllene being present in all plants. All cannabis varieties were effective to different degree against Gram (+) and Gram (-) bacteria as well as on spore germination and vegetative development of phytopathogenic fungi. These effects were not correlated to the content of major cannabinoids such as CBD or THC, but with the presence of a complex terpenes profile. The effectiveness of the extracts allowed to reduce the necessary doses of a widely used commercial antifungal to prevent the development of fungal spores.
Conclusion: All the extracts of the analysed cannabis varieties showed antibacterial and antifungal activities. In addition, plants belonging to the same chemotype showed different antimicrobial activity, demonstrating that the classification of cannabis strains based solely on THC and CBD content is not sufficient to justify their biological activities and that other compounds present in the extracts are involved in their action against pathogens. Cannabis extracts act in synergy with chemical fungicides, allowing to reduce its doses.”
https://pubmed.ncbi.nlm.nih.gov/37400009/
https://www.sciencedirect.com/science/article/abs/pii/S0378874123007079?via%3Dihub
Cannabidiol reduces LPS-induced nociception via endocannabinoid system activation
“Bacterial infections are often accompanied by fever and generalized muscle pain. However, the treatment of pain with an infectious etiology has been overlooked. Thus, we investigated the impact of cannabidiol (CBD) in bacterial lipopolysaccharide (LPS)-induced nociception.
Male Swiss mice received intrathecal (i.t.) LPS injection, and the nociceptive threshold was measured by the von Frey filaments test. Spinal involvement of the cannabinoid CB2 receptor, toll-like receptor 4 (TLR4), microglia and astrocytes were evaluated by i.t. administration of their respectively antagonists or inhibitors. Western blot, immunofluorescence, ELISA and liquid chromatography-mass spectrometry were used to assess Cannabinoid CB2 receptors and TLR4 spinal expression, proinflammatory cytokines and endocannabinoid levels. CBD was administered intraperitoneally at 10 mg/kg.
The pharmacological assay demonstrated TLR4 participation in LPS-induced nociception. In addition, spinal TLR4 expression and proinflammatory cytokine levels were increased in this process.
CBD treatment prevented LPS-induced nociception and TLR4 expression.
AM630 reversed antinociception and reduced CBD-induced endocannabinoids upregulation. Increased spinal expression of the cannabinoid CB2 receptor was also found in animals receiving LPS, which was accompanied by reduced TLR4 expression in CBD-treated mice.
Taken together, our findings indicated that CBD is a potential treatment strategy to control LPS-induced pain by attenuating TLR4 activation via the endocannabinoid system.”
Cannabidiol and Cannabigerol Exert Antimicrobial Activity without Compromising Skin Microbiota
“Cannabidiol (CBD) and cannabigerol (CBG) are two pharmacologically active phytocannabinoids of Cannabis sativa L. Their antimicrobial activity needs further elucidation, particularly for CBG, as reports on this cannabinoid are scarce. We investigated CBD and CBG’s antimicrobial potential, including their ability to inhibit the formation and cause the removal of biofilms.
Our results demonstrate that both molecules present activity against planktonic bacteria and biofilms, with both cannabinoids removing mature biofilms at concentrations below the determined minimum inhibitory concentrations. We report for the first time minimum inhibitory and lethal concentrations for Pseudomonas aeruginosa and Escherichia coli (ranging from 400 to 3180 µM), as well as the ability of cannabinoids to inhibit Staphylococci adhesion to keratinocytes, with CBG demonstrating higher activity than CBD. The value of these molecules as preservative ingredients for cosmetics was also assayed, with CBG meeting the USP 51 challenge test criteria for antimicrobial effectiveness. Further, the exact formulation showed no negative impact on skin microbiota.
Our results suggest that phytocannabinoids can be promising topical antimicrobial agents when searching for novel therapeutic candidates for different skin conditions. Additional research is needed to clarify phytocannabinoids’ mechanisms of action, aiming to develop practical applications in dermatological use.”
https://pubmed.ncbi.nlm.nih.gov/36768709/
“This report compares CBD and CBG’s antimicrobial effectiveness and further cements phytocannabinoids’ potential to be used as antimicrobial agents. Both molecules’ antimicrobial capacity strongly depends on the target microorganism, namely whether it is Gram-negative or Gram-positive. Nonetheless, we were able to determine MICs for all tested strains, including S. pyogenes, E. coli, and P. aeruginosa. It is of note that CBG revealed a stronger antimicrobial effect than CBD, particularly in the challenge test and in the antibiofilm assay. Further studies are needed to understand these discrepancies, as they may be connected to structural differences, receptor-binding affinity, or another mechanism other than a receptor-mediated one. Since no significant impact on the skin microbiota was observed and given its current widespread use, both CBD and CBG might be considered safe. Thus, we can assume that the development of topical formulations with active concentrations of CBG and/or CBD might represent a promising approach to tackle skin conditions where microorganisms and inflammation play a fundamental role, including psoriasis, atopic dermatitis, and acne.”
Cannabis sativa CBD Extract Exhibits Synergy with Broad-Spectrum Antibiotics against Salmonella enterica subsp. Enterica serovar typhimurium
“New generation antibiotics are needed to combat the development of resistance to antimicrobials. One of the most promising new classes of antibiotics is cannabidiol (CBD). It is a non-toxic and low-resistance chemical that can be used to treat bacterial infections.
The antibacterial activity of Cannabis sativa L. byproducts, specifically CBD, has been of growing interest in the field of novel therapeutics. As research continues to define and characterize the antibacterial activity that CBD possesses against a wide variety of bacterial species, it is important to examine potential interactions between CBD and common therapeutics such as broad-spectrum antibiotics.
In this study it is demonstrated that CBD-antibiotic (combination of CBD and antibiotic) co-therapy can effectively fight Salmonella typhimurium (S. typhimurium) via membrane integrity disruption. This research serves to examine the potential synergy between CBD and three broad-spectrum antibiotics (ampicillin, kanamycin, and polymyxin B) for potential CBD-antibiotic co-therapy. In this study, it is revealed that S. typhimurium growth is inhibited at very low dosages of CBD-antibiotic.
This interesting finding demonstrates that CBD and CBD-antibiotic co-therapies are viable novel alternatives to combating S. typhimurium.”
https://pubmed.ncbi.nlm.nih.gov/36557613/
“The decrease in antibiotic development over the 21st century has exacerbated the need for new antibacterial agents as well as new methodologies designed to retain the efficacy of current antibiotics. CBD extract from C. sativa has been presented as a promising antibacterial agent with in vitro efficacy against several relevant bacterial pathogens including Staphylococcus aureus, Streptococcus pneumoniae, Salmonella spp. Clostridium difficile, Neisseria spp., Moraxella catarrhalis, and Legionella pneumophila. This antibacterial activity achieved through membrane disruption of both Gram-positive and Gram-negative bacterial species presents CBD as a unique and particularly effective class of antibacterial agents.”
Anti-Bacterial Effect of Cannabidiol against the Cariogenic Streptococcus mutans Bacterium: An In Vitro Study
“Dental caries is caused by biofilm-forming acidogenic bacteria, especially Streptococcus mutans, and is still one of the most prevalent human bacterial diseases. The potential use of cannabidiol (CBD) in anti-bacterial therapies has recently emerged.
Here we have studied the anti-bacterial and anti-biofilm activity of CBD against S. mutans. We measured minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC). The bacterial growth and changes in pH values were measured in a kinetic study. The biofilm biomass was assessed by Crystal Violet staining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) metabolic assay. Spinning Disk Confocal Microscopy (SDCM) was used to assess biofilm structure, bacterial viability and extracellular polysaccharide (EPS) production.
CBD inhibited S. mutans planktonic growth and biofilm formation in a dose-dependent manner, with similar MIC and MBIC values (5 µg/mL). CBD prevented the bacteria-mediated reduction in pH values that correlated with bacterial growth inhibition. SDCM showed a decrease of 50-fold in live bacteria and EPS production. CBD significantly reduced the viability of preformed biofilms at 7.5 µg/mL with an 80 ± 3.1% reduction of metabolic activity. At concentrations above 20 µg/mL, there was almost no bacterial recovery in the CBD-treated preformed biofilms even 48 h after drug withdrawal.
Notably, precoating of the culture plate surfaces with CBD prior to incubation with bacteria inhibited biofilm development. Additionally, CBD was found to induce membrane hyperpolarization in S. mutans. Thus, CBD affects multiple processes in S. mutans including its cariogenic properties.
In conclusion, we show that CBD has a strong inhibitory effect against cariogenic bacteria, suggesting that it is a potential drug adjuvant for reducing oral pathogenic bacterial load as well as protecting against dental caries.”
https://pubmed.ncbi.nlm.nih.gov/36555519/
“We have shown that the mode of action of CBD against S. mutans is multifactorial and attributed to: inhibition of bacterial growth and subsequently hindrance of biofilm formation, diminished biofilm metabolic activity and prevention of bacterial recovery within the biofilms following CBD treatment. Some of these effects can be attributed to the membrane hyperpolarization caused by CBD. The combined anti-bacterial and anti-metabolic effects of CBD contribute to the prevention in pH drop with implications for being a potential adjuvant drug in protecting against dental caries.”
Antimicrobial and Cytotoxic Effects of Cannabinoids: An Updated Review with Future Perspectives and Current Challenges
“The development of new antibiotics is urgently needed to combat the threat of bacterial resistance. New classes of compounds that have novel properties are urgently needed for the development of effective antimicrobial agents.
The extract of Cannabis sativa L. has been used to treat multiple ailments since ancient times. Its bioactivity is largely attributed to the cannabinoids found in its plant. Researchers are currently searching for new anti-infective agents that can treat various infections. Although its phytocannabinoid ingredients have a wide range of medical benefits beyond the treatment of infections, they are primarily associated to psychotropic effects.
Different cannabinoids have been demonstrated to be helpful against harmful bacteria, including Gram-positive bacteria. Moreover, combination therapy involving the use of different antibiotics has shown synergism and broad-spectrum activity. The purpose of this review is to gather current data on the actions of Cannabis sativa (C. sativa) extracts and its primary constituents such as terpenes and cannabinoids towards pathogens in order to determine their antimicrobial properties and cytotoxic effects together with current challenges and future perspectives in biomedical application.”
https://pubmed.ncbi.nlm.nih.gov/36297340/
“C. sativa is a plant with an untapped potential. This versatile plant can be used for various purposes. Given its complex metabolic profile and excessive use as a recreational substance, its therapeutic benefits should not be ignored or overshadowed. Due to the limited effectiveness of antibiotics against MDR bacteria, the use of these drugs can be limited. This is why the discovery of an antimicrobial agent that can be used by plants has been regarded as a great step in the development of anti-infectives [8]. Multiple cannabinoids have been shown to have potent antimicrobial properties against Gram-positive pathogens, such as MRSA. In vitro studies have shown that cannabinoids can be useful in the removal of harmful microbes from the environment. Combination therapy with antibiotics that have different modes of action has shown broad-spectrum activities and synergism. There is also evidence that compounds found in C. sativa can have antimicrobial properties. This suggests that further investigations are needed to understand their potential. As the development of antibiotic resistance continues, cannabinoids have the potential to become a new source of treatment for bacterial infections.”
Antibacterial Effects of Phytocannabinoids
“Antibiotics are used as the first line of treatment for bacterial infections. However, antibiotic resistance poses a significant threat to the future of antibiotics, resulting in increased medical costs, hospital stays, and mortality. New resistance mechanisms are emerging and spreading globally, impeding the success of antibiotics in treating common infectious diseases.
Recently, phytocannabinoids have been shown to possess antimicrobial activity on both Gram-negative and Gram-positive bacteria. The therapeutic use of phytocannabinoids presents a unique mechanism of action to overcome existing antibiotic resistance.
Future research must be carried out on phytocannabinoids as potential therapeutic agents used as novel treatments against resistant strains of microbes.”
https://pubmed.ncbi.nlm.nih.gov/36143430/
“Current antibiotic treatments have limited efficacy against multidrug-resistant bacteria, causing a significant challenge for prescribing physicians. A lack of effective therapies or new antibiotics requires the development of alternative antimicrobial therapies. Research has shown phytocannabinoids and CB2 agonists to exhibit antibiotic activity against a variety of Gram-positive and Gram-negative bacteria. Although their antimicrobial activity is limited in terms of Gram-negative bacteria, they offer therapeutic potential when administered as an adjunct treatment with an outer membrane perturbing molecule to facilitate the permeation of compounds that are effective on Gram-positive bacteria. Research has also shown synergy supporting the potential for combination therapy both in vivo and in vitro. Furthermore, CB2 agonists, such as β-caryophyllene, are widely used in industry as food additives and traditional medicine, and many are FDA approved and generally recognised as safe (GRAS), making them a good option for a novel therapeutic. The studies presented in this review suggest an attractive potential for cannabinoid-based antibacterial treatments.”
The Antimicrobial Properties of Cannabis and Cannabis-Derived Compounds and Relevance to CB2-Targeted Neurodegenerative Therapeutics
“Cannabinoid receptor 2 (CB2) is of interest as a much-needed target for the treatment or prevention of several neurogenerative diseases. However, CB2 agonists, particularly phytocannabinoids, have been ascribed antimicrobial properties and are associated with the induction of microbiome compositional fluxes. When developing novel CB2 therapeutics, CB2 engagement and antimicrobial functions should both be considered. This review summarizes those cannabinoids and cannabis-informed molecules and preparations (CIMPs) that show promise as microbicidal agents, with a particular focus on the most recent developments. CIMP-microbe interactions and anti-microbial mechanisms are discussed, while the major knowledge gaps and barriers to translation are presented. Further research into CIMPs may proffer novel direct or adjunctive strategies to augment the currently available antimicrobial armory. The clinical promise of CIMPs as antimicrobials, however, remains unrealized. Nevertheless, the microbicidal effects ascribed to several CB2 receptor-agonists should be considered when designing therapeutic approaches for neurocognitive and other disorders, particularly in cases where such regimens are to be long-term. To this end, the potential development of CB2 agonists lacking antimicrobial properties is also discussed.”
Antibacterial, Antibiofilm, and Antioxidant Activity of 15 Different Plant-Based Natural Compounds in Comparison with Ciprofloxacin and Gentamicin
“Plant-based natural compounds (PBCs) are comparatively explored in this study to identify the most effective and safe antibacterial agent/s against six World Health Organization concern pathogens. Based on a contained systematic review, 11 of the most potent PBCs as antibacterial agents are included in this study. The antibacterial and antibiofilm efficacy of the included PBCs are compared with each other as well as common antibiotics (ciprofloxacin and gentamicin). The whole plants of two different strains of Cannabis sativa are extracted to compare the results with sourced ultrapure components. Out of 15 PBCs, tetrahydrocannabinol, cannabidiol, cinnamaldehyde, and carvacrol show promising antibacterial and antibiofilm efficacy. The most common antibacterial mechanisms are explored, and all of our selected PBCs utilize the same pathway for their antibacterial effects. They mostly target the bacterial cell membrane in the initial step rather than the other mechanisms. Reactive oxygen species production and targeting [Fe-S] centres in the respiratory enzymes are not found to be significant, which could be part of the explanation as to why they are not toxic to eukaryotic cells. Toxicity and antioxidant tests show that they are not only nontoxic but also have antioxidant properties in Caenorhabditis elegans as an animal model.”
https://pubmed.ncbi.nlm.nih.gov/36009966/
“Some of the PBCs tested, including THC, CBD, cinnamaldehyde, and carvacrol, showed quite promising antibacterial and antibiofilm potency in comparison with common antibiotics (ciprofloxacin and gentamicin). They are not only non-toxic but also have antioxidant properties as well.”