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Icariin in Combination with Amoxycillin-Clavulanate and Ampicillin, but Not Vancomycin, Increases Antibiotic
María Cardells Peris1, Alba Martínez1, Marina Pascual Ortíz1
1Faculty of Health Sciences, Universidad CEU Cardenal Herrera, C/Ramon y Cajal s/n, Alfara del Patriarca, 46115 Valencia, Spain.
Abstract:
The widespread irrational use of antibiotics in recent years has resulted in an increase in the detection of multi-resistant bacterial strains, particularly methicillin-resistant Staphylococcus aureus (MRSA). The use of natural derivatives such as flavonoids is postulated as one of the most promising avenues to solve this emerging public health problem. The objective of the present study is to characterize the antimicrobial activity of icariin, a flavonoid compound isolated from a variety of plants of the Epimedium genus, against human and animal clinical MRSA isolates. Our study found that icariin alone did not have any antimicrobial effect on S. aureus or MRSA clinical isolates. However, icariin enhanced the effect of amoxycillin-clavulanate or ampicillin, whereas no effect was seen when used in combination with vancomycin. Specifically, co-incubation of S. aureus with amoxycillin-clavulanate plus icariin resulted in an increased proportion of dead cells, suggesting that this flavonoid potentially increases antimicrobial activity when used in combination with the beta-lactam antibiotic amoxycillin-clavulanate. Furthermore, we demonstrate that co-incubation of S. aureus with AmoxyClav plus icariin resulted in increased membrane disruption and growth inhibition. This study demonstrates the potential utility of icariin in permitting lower antibiotic therapeutic doses in alignment with strategies to reduce the spread of antibiotic resistance. Further research is required to determine the optimum concentration of icariin and to define clinically relevant combinations of flavonoid and antibiotic.
Insights
Icariin, a natural flavonoid, shows no antimicrobial effect alone but enhances amoxycillin-clavulanate activity against MRSA. This combination increases bacterial cell death and growth inhibition, potentially reducing antibiotic resistance.
Area of Science:
- Microbiology
- Pharmacology
- Natural Product Chemistry
Background:
- Antibiotic resistance, particularly from methicillin-resistant Staphylococcus aureus (MRSA), is a growing public health concern due to widespread irrational antibiotic use.
- Natural compounds like flavonoids are being investigated as potential solutions to combat multi-drug resistant bacteria.
- Icariin, a flavonoid from Epimedium plants, is a candidate for antimicrobial applications.
Purpose of the Study:
- To evaluate the antimicrobial activity of icariin against clinical isolates of MRSA.
- To determine if icariin can potentiate the efficacy of existing antibiotics against MRSA.
- To explore the mechanisms by which icariin might affect MRSA.
Main Methods:
- Antimicrobial susceptibility testing of icariin alone and in combination with antibiotics (amoxycillin-clavulanate, ampicillin, vancomycin) against MRSA clinical isolates.
- Assessment of bacterial cell viability and membrane integrity upon co-incubation with icariin and antibiotics.
- Microscopic examination to observe effects on bacterial growth and morphology.
Main Results:
- Icariin alone exhibited no antimicrobial activity against Staphylococcus aureus or MRSA.
- Icariin significantly enhanced the antimicrobial effects of amoxycillin-clavulanate and ampicillin, but not vancomycin.
- Co-incubation with amoxycillin-clavulanate and icariin led to increased bacterial cell death, membrane disruption, and growth inhibition.
Conclusions:
- Icariin demonstrates potential as an adjuvant therapy, enhancing the efficacy of certain beta-lactam antibiotics against MRSA.
- Combining icariin with antibiotics like amoxycillin-clavulanate may allow for lower therapeutic antibiotic doses, aiding in strategies to combat antibiotic resistance.
- Further research is needed to optimize icariin concentrations and identify clinically relevant antibiotic-flavonoid combinations.
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