Abstract
α-humulene, a sesquiterpene found in essential oils of various plant species, has garnered
interest due to its potential therapeutic applications. This scoping review aims to
consolidate α-humuleneʼs evidence base, informing clinical translation, and guiding future research
directions. A scoping review was conducted of EMBASE, MEDLINE, and PubMed databases
up to 14th July 2023. All studies describing original research on α-humulene extraction, as well as pre-clinical and clinical research, were included
for review. Three hundred and forty articles were analysed. α-humulene yields ranged from negligible to 60.90% across plant species. In vitro experiments demonstrated cytotoxicity against adenocarcinomas (such as colorectal,
pulmonary, breast, prostatic, lung, and ovarian), with varying responses in other
cell models. Mechanistic insights revealed its involvement in mitochondrial dysfunction,
diminished intracellular glutathione levels, and
the induction of oxidative stress. In rodent studies, oral administration of α-humulene at 50 mg/kg reduced inflammation markers in paw oedema and ovalbumin-induced
airway inflammation. Intraperitoneal administration of α-humulene (50 – 200 mg/kg) exhibited cannabimimetic properties through cannabinoid
1 and adenosine A2a receptors. α-humulene also exhibited a multitude of properties with potential scope for therapeutic
utilisation. However, there is a paucity of studies that have successfully translated
this research into clinical populations with the associated disease. Potential barriers
to clinical translation were identified, including yield variability, limited isolation
studies, and challenges associated with terpene bioavailability. Consequently, rigorous
pharmacokinetic studies and further mechanistic investigations are warranted to effectively
uncover the potential of α-humulene.
Keywords
terpenes - anti-bacterial agents -
α-humulene -
Humulus lupulus
-
Cannabis indica
-
Cannabis sativa
- Cannabaceae
