Synergistic effects of anti-MRSA herbal extracts combined with antibiotics

2020 ◽  
Vol 15 (13) ◽  
pp. 1265-1276
Author(s):  
Mei Bao ◽  
Lulu Zhang ◽  
Bin Liu ◽  
Li Li ◽  
Yin Zhang ◽  
...  

MRSA is a super drug-resistant bacterium. Developing new drug or therapeutic strategies against MRSA is urgently needed. Increasing evidence has shown that herbal extracts and antibiotics can have synergistic effects against MRSA. This review focuses on commonly used antibiotics combined with herbal extracts against MRSA and the corresponding mechanisms. Through systematic analysis, we found that herbal extracts combined with antibiotics, such as β-lactams, quinolones, aminoglycosides, tetracyclines and glycopeptides, could greatly enhance the antibacterial effects of the antibiotics, reduce the dosage and toxic side effects, and reverse MRSA resistance. Therefore, we conclude that herbal extracts combined with antibiotics may be a promising strategy to combat MRSA. This review provides a novel idea for overcoming antibiotic resistance.

Author(s):  
Hassan Zgheib ◽  
Djamel Drider ◽  
Yanath Belguesmia

Bacteriocins are antimicrobial peptides some of which are endowed with antiviral, anticancer and antibiofilm properties. These properties could be improved through synergistic interactions of these bacteriocins with other bioactive molecules such as antibiotics, phages, nanoparticles and essential oils. A number of studies are steadily reporting the effects of these combinations as new and potential therapeutic strategies in the future, as they may offer many incentives over existing therapies. In particular, bacteriocins can benefit from combination with nanoparticles which can improve their stability and solubility, and protect them from enzymatic degradation, reduce their interactions with other molecules and improve their bioavailability. Furthermore, the combination of bacteriocins with other antimicrobials is foreseen as a way to reduce the development of antibiotic resistance due to the involvement of several modes of action. Another relevant advantage of these synergistic combinations is that it decreases the concentration of each antimicrobial component, thereby reducing their side effects such as their toxicity. In addition, combination can extend the utility of bacteriocins as antiviral or anticancer agents. Thus, in this review, we report and discuss the synergistic effects of bacteriocin combinations as medicines, and also for other diverse applications including, antiviral, antispoilage, anticancer and antibiofilms.


2019 ◽  
Vol 20 (22) ◽  
pp. 5790 ◽  
Author(s):  
Yu-Wei Chang ◽  
Wan-Chun Huang ◽  
Chun-Yu Lin ◽  
Wen-Hung Wang ◽  
Ling-Chien Hung ◽  
...  

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has become a critical global concern. Identifying new candidates of anti-S. aureus agents is urgently required because the therapeutic strategies for infected patients are limited currently. Therefore, the present study investigated whether Tellimagrandin II (TGII), a pure compound extracted from the shells of Trapa bispinosa, exhibits antibacterial effects against MRSA. We first showed that TGII exerted potent inhibitory activity against MRSA with a minimum inhibitory concentration of 128 μg/mL. The obtained fractional inhibitory concentration suggested that TGII could alone exert antistaphylococcal activity, and TGII combined with low doses of antibiotics displayed synergistic effects against MRSA. Moreover, we found that TGII exerted bactericidal activity by reducing the expression of mecA followed by the negative regulation of the penicillin-binding protein 2a (PBP2a) of MRSA. Transmission electron microscopy (TEM) images further confirmed that TGII destroyed the integrity of the cell wall of MRSA and caused the loss of cytoplasm content. In conclusion, we evidenced the antibacterial effects of TGII against MRSA, which enables the effective dose of current antibiotics to be reduced and the predicament of drug-resistant S. aureus isolates to be overcome.


2013 ◽  
Vol 58 (3) ◽  
pp. 1622-1629 ◽  
Author(s):  
Ramamourthy Gopal ◽  
Young Gwon Kim ◽  
Jun Ho Lee ◽  
Seog Ki Lee ◽  
Jeong Don Chae ◽  
...  

ABSTRACTThe increasing prevalence of drug-resistant pathogens highlights the need to identify novel antibiotics. Here we investigated the efficacies of four new antimicrobial peptides (AMPs) for potential drug development. The antibacterial activities, synergistic effects, and antibiofilm properties of the four chimeric AMPs were tested againstAcinetobacter baumannii, an emerging Gram-negative, nosocomial, drug-resistant pathogen. NineteenA. baumanniistrains resistant to ampicillin, cefotaxime, ciprofloxacin, tobramycin, and erythromycin were isolated at a hospital from patients with cholelithiasis. All four peptides exhibited significant antibacterial effects (MIC = 3.12 to 12.5 μM) against all 19 strains, whereas five commercial antibiotics showed little or no activity against the same pathogens. An exception was polymyxin, which was effective against all of the strains tested. Each of the peptides showed synergy against one or more strains when administered in combination with cefotaxime, ciprofloxacin, or erythromycin. The peptides also exhibited an ability to prevent biofilm formation, which was not seen with cefotaxime, ciprofloxacin, or erythromycin, though polymyxin also inhibited biofilm formation. Indeed, when administered in combination with ciprofloxacin, the AMP HPMA exerted a potent synergistic effect againstA. baumanniibiofilm formation. Collectively, our findings indicate that the AMPs tested have no cytotoxicity but possess potent antibacterial and antibiofilm activities and may act synergistically with commercial antibiotics.


2019 ◽  
Author(s):  
Chiara Rezzoagli ◽  
Martina Archetti ◽  
Ingrid Mignot ◽  
Michael Baumgartner ◽  
Rolf Kümmerli

AbstractAntibiotics are losing efficacy due to the rapid evolution and spread of resistance. Treatments targeting bacterial virulence factors have been considered as alternatives because they target virulence instead of pathogen viability, and should therefore exert weaker selection for resistance than conventional antibiotics. However, antivirulence treatments rarely clear infections, which compromises their clinical applications. Here, we explore the potential of combining antivirulence drugs with antibiotics against the opportunistic human pathogen Pseudomonas aeruginosa. We combined two antivirulence compounds (gallium, a siderophore-quencher, and furanone C-30, a quorum sensing-inhibitor) together with four clinically relevant antibiotics (ciprofloxacin, colistin, meropenem, tobramycin) in 9×9 drug concentration matrices. We found that drug-interaction patterns were concentration dependent, with promising levels of synergies occurring at intermediate drug concentrations for certain drug pairs. We then tested whether antivirulence compounds are potent adjuvants, especially when treating antibiotic resistant clones. We found that the addition of antivirulence compounds to antibiotics could restore growth inhibition for most antibiotic resistant clones, and even abrogate or reverse selection for resistance in five drug combination cases. Molecular analyses suggest that selection against resistant clones occurs when resistance mechanisms involve restoration of protein synthesis, but not when efflux pumps are upregulated. Altogether, our work provides a first systematic analysis of antivirulence-antibiotic combinatorial treatments and suggests that such combinations have a high potential to be both effective in treating infections and in limiting the spread of antibiotic resistance.


2020 ◽  
Author(s):  
Laura Lafon-Hughes

BACKGROUND COVID-19 pandemic prompts the study of coronavirus biology and search of putative therapeutic strategies. OBJECTIVE To compare SARS-CoV-2 genome-wide structure and proteins with other coronaviruses, focusing on putative coronavirus-specific or SARS-CoV-2 specific therapeutic designs. METHODS The genome-wide structure of SARS-CoV-2 was compared to that of SARS and other coronaviruses in order to gain insights, doing a literature review through Google searches. RESULTS There are promising therapeutic alternatives. Host cell targets could be modulated to hamper viral replication, but targeting viral proteins directly would be a better therapeutic design, since fewer adverse side effects would be expected. CONCLUSIONS Therapeutic strategies (Figure 1) could include the modulation of host targets (PARPs, kinases) , competition with G-quadruplexes or nucleoside analogs to hamper RDRP. The nicest anti-CoV options include inhibitors of the conserved essential viral proteases and drugs that interfere ribosome slippage at the -1 PRF site.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Nursenem Karaca ◽  
Görkem Şener ◽  
Betül Demirci ◽  
Fatih Demirci

AbstractCombination of various compounds and essential oils for pharmaceutical formulations withdraw attention. In this present study, it was aimed to evaluate the in vitro potential synergistic antibacterial effect of Lavandula latifolia (spike lavender) essential oil with camphor by using the checkerboard method against the human pathogens; Staphylococcus aureus and Listeria monocytogenes. Pharmacopoeia quality L. latifolia essential oil and racemic camphor were analyzed and verified by GC-FID and GC/MS, simultaneously. In vitro antibacterial activity of essential oil and camphor (MIC range: 0.16–20 mg/mL) and standard antimicrobial clarithromycin (MIC range: 0.125–16 μg/mL) were carried out by broth microdilution against S. aureus and L. monocytogenes standard strains, respectively. Resulting antibacterial effects were evaluated for their fractional inhibitory concentrations (FICs) as antagonistic, additive and synergistic effects. The analytical results showed that the major component of essential oil was linalool (45.2%) and 1,8-cineole (25.6%). Antibacterial effects of essential oil were determined as MIC 1.25–5 mg/mL. As a result of the experiments, L. latifolia essential oil–camphor combinations were identified as “synergistic (FIC ≤ 0.5), and additive (0.5 < FIC ≤ 1)” in the respective combinations, suggesting further evaluation for formulations for potential antimicrobial applications in food and pharmaceuticals.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Sindt ◽  
T Madej ◽  
S Grimm ◽  
M Knaut

Abstract Objectives First generation baroreflex activation therapy (BAT) devices showed clinical efficacy in patients with drug-resistant arterial hypertension (AHT), but the safety profile was insufficient. Data regarding efficacy of second-generation devices were generated mostly from office blood pressure (BP) measurements or short-term 24-hour ambulatory blood pressure measurements (ABPM). We present a mid-term prospective registry to evaluate the efficacy and safety of recent BAT devices. Purpose The purpose of our study was to find a method that helps patients with drug-resistant arterial hypertension to control their blood pressure. Further we sought to reduce the overall amount of antihypertensive drugs to lessen side effects, as well as the effects of polypharmacy. Methods All patients receiving Barostim neo between November 2013 and June 2019 for resistant AHT were prospectively included into this observational study. ABPM was performed at baseline, in 3-month intervals in the first year after BAT implantation and in 6-month intervals afterwards for up to 42 months. Patients were assigned into two groups of responders and non-responders. Non-responders had a mean blood pressure drop (BPD) below 5mmHg. Responders in turn were categorized into 3 sub-groups (low-BPD between 5–9 mmHg, medium-BPD between 10–19 mmHg and high-BPD ≥20 mmHg). The primary efficacy end-points were changes in systolic and diastolic BP and number of antihypertensive medications. The primary safety end point was BAT-related major adverse events (MAE). Results 64 patients (mean age 63 years, 67% males) were included. Only patients who completed a 24-hour ABPM during a follow up were counted in the statistical analysis. We had an overall responder rate of 67.8%. Out of those 15.4% had low-BPD, 38.4% medium-BPD and 46.2% had a high-BPD. Systolic BP decreased over the 3.5-years period from 168±17 mmHg to 149±19 mmHg (n=19, mean change −18.8 mmHg; 95% confidence interval [CI]: −29.32 to −8.36; p&lt;0.0007). Diastolic BP decreased from 97±16 to 85±12 mmHg (n=19, mean change −11.7 mmHg; 95% CI: −19.2 to −4.2; p&lt;0.0021). The mean number of antihypertensive drugs was reduced from 6.9±1.3 to 5.2±1.5 (n=19, mean change −1.7; 95% CI: −0.8 to −0.27; p&lt;0.0009). The time course of primary end-points is shown in Fig.1. Freedom from BAT-related MAE was 93.5%. 4 perioperative complications (1 pocket bleeding, 1 pocket infection, 1 N. hypoglossus palsy, 1 hoarseness) resolved without residual side effects. There were five non BAT related deaths (7,8%) in the follow up period. Conclusion Systolic and diastolic ABP, as well as number and dosage of antihypertensive drugs decreased significantly during 3.5-years follow-up after Barostim neo implantation in 64 consecutive patients (of whom 62 completed at least one follow-up). No MAE associated with BAT were observed after the perioperative period. However, further controlled trials are needed to confirm the long-term efficacy of BAT. Figure 1. Mean blood pressure drop Funding Acknowledgement Type of funding source: None


Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 321
Author(s):  
Shekh Sabir ◽  
Tsz Tin Yu ◽  
Rajesh Kuppusamy ◽  
Basmah Almohaywi ◽  
George Iskander ◽  
...  

The quorum sensing (QS) system in multi-drug-resistant bacteria such as P. aeruginosa is primarily responsible for the development of antibiotic resistance and is considered an attractive target for antimicrobial drug discovery. In this study, we synthesised a series of novel selenourea and thiourea-containing dihydropyrrol-2-one (DHP) analogues as LasR antagonists. The selenium DHP derivatives displayed significantly better quorum-sensing inhibition (QSI) activities than the corresponding sulphur analogues. The most potent analogue 3e efficiently inhibited the las QS system by 81% at 125 µM and 53% at 31 µM. Additionally, all the compounds were screened for their minimum inhibitory concentration (MIC) against the Gram-positive bacterium S. aureus, and interestingly, only the selenium analogues showed antibacterial activity, with 3c and 3e being the most potent with a MIC of 15.6 µM.


Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1046
Author(s):  
Yinghan Chan ◽  
Xun Hui Wu ◽  
Buong Woei Chieng ◽  
Nor Azowa Ibrahim ◽  
Yoon Yee Then

Biofilm formation represents a significant cause of concern as it has been associated with increased morbidity and mortality, thereby imposing a huge burden on public healthcare system throughout the world. As biofilms are usually resistant to various conventional antimicrobial interventions, they may result in severe and persistent infections, which necessitates the development of novel therapeutic strategies to combat biofilm-based infections. Physicochemical modification of the biomaterials utilized in medical devices to mitigate initial microbial attachment has been proposed as a promising strategy in combating polymicrobial infections, as the adhesion of microorganisms is typically the first step for the formation of biofilms. For instance, superhydrophobic surfaces have been shown to possess substantial anti-biofilm properties attributed to the presence of nanostructures. In this article, we provide an insight into the mechanisms underlying biofilm formation and their composition, as well as the applications of nanomaterials as superhydrophobic nanocoatings for the development of novel anti-biofilm therapies.


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