For millennia manuka honey has been shown to have wide ranging medicinal properties, which have more recently been identified for its broad spectrum of antimicrobial activity. In a new study, researchers at Aston University combined manuka honey and the drug amikacin in a lab-based nebulization formulation to treat the harmful bacterial lung infection Mycobacterium abscessus, which usually affects patients with cystic fibrosis or bronchiectasis.
Nolan et al. demonstrate the utility of manuka honey for incorporation into nebulized antibiotic treatment for respiratory infections, in particular Mycobacterium abscessus. Image credit: Yevgen Kyrylko.
Mycobacterium abscessus is a rapidly growing non-tuberculous mycobacteria commonly isolated from the environment.
It is an opportunistic pathogen that causes pulmonary infections in patients with pre-existing lung conditions such as cystic fibrosis and bronchiectasis, as well as causing skin and soft tissue infections.
Treatment of Mycobacterium abscessus infections is challenging due to the intrinsically drug resistant nature of this species.
Currently, patients are given a cocktail of antibiotics, consisting of 12 months or more of antimicrobial chemotherapy and often doesn’t result in a cure.
The dosage of amikacin usually used on a patient to kill the infection is 16 micrograms per milliliter.
But Dr. Victoria Nolan and her colleagues from Aston University found that the new combination using manuka honey, required a dosage of just 2 micrograms per milliliter of amikacin — resulting in a one eighth reduction in the dosage of the drug.
“The antimicrobial activity of honey has been established for millennia and explored in depth against a range of bacterial pathogens,” they said.
“Manuka honey in particular has gained significant interest for its enhanced antimicrobial activity and broad spectrum of activity.”
“Derived from Leptospermum spp., manuka honey’s antimicrobial activity is attributed to the presence of methylglyoxal (MGO), which is not found in most other honeys.”
“This is due to dihydroxyacetone within the nectar of manuka flowers, which is a precursor of MGO.”
In their study, Dr. Nolan and co-authors used samples of the bacteria Mycobacterium abscessus taken from 16 infected cystic fibrosis patients.
They then tested a combination of amikacin and manuka honey to discover what dosage was required to kill the bacteria.
As part of the study they used a lab-based lung model and nebulizer — a device that produces a fine spray of liquid often used for inhaling a medicinal drug.
By nebulizing manuka honey and amikacin together, it was found they could improve bacterial clearance, even when using lower doses of amikacin, which would result in less life-changing side-effects to the patient.
“So far treatment of Mycobacterium abscessus pulmonary infections can be problematic due to its drug resistant nature. The variety of antibiotics required to combat infection result in severe side effects,” Dr. Nolan said.
“However, the use of this potential treatment combining amikacin and manuka honey shows great promise as an improved therapy for these terrible pulmonary infections.”
“There is a need for better treatment outcomes and in the future we hope that this potential treatment can be tested further.”
The results appear in the journal Microbiology.
Victoria C. Nolan et al. 2022. In vitro synergy between manuka honey and amikacin against Mycobacterium abscessus complex shows potential for nebulisation therapy. Microbiology 168 (9); doi: 10.1099/mic.0.001237