Science of Terpenes
Updated: Dec 20, 2019
What makes a cannabis strain right for you? With so many options emerging in the cannabis medicinal market, choosing the right strain is overwhelming for many patients. I find it helpful to stick to the mantra "the nose knows best". Each strain has a unique smell profile thanks to organic compounds called terpenes. Terpenes are prevalent in various species throughout the plant kingdom. They help plants fight pathogens, attract pollinators, and even repel herbivores. Cannabis is unique because its family Cannabaceae has shown to hold a high concentration of these beneficial compounds. Up to 98% of known terpenes have been found in the essential oils of Cannabis sativa. Each terpene has a unique smell, and this can be utilized as a deciding factor in determining medicinal value. For those looking for a more fool-proof method, review the test results of the terpene profile. Terpene health benefits have been analyzed by many scientists and published in multiple peer reviewed journals. This documented evidence is essential in analyzing the health benefits of cannabis.
Now, let's take a deeper look into the most common cannabis terpenes and recent scientific health findings.
Smell profile: earthy, herbal (bay leaves, thyme, parsley, basil)
A recent study in mice revealed myrcene decreased the activation and expression of inflammatory enzymes. These anti-inflammatory and anti-catabolic effects in the cell imply a potential to slow down the progression of osteoarthritis.
Myrcene also showed evidence of helping restore heart tissue damage after a stroke in mice by increasing the levels of glutathione and anti-oxidative enzymes.
In another study, oral consumption of myrcene protected mice against an environmental pollutant that induced liver damage. Oral consumption also revealed to promote anti-ulcer activity.
Myrcene exerts its anti-mutagenic activity by inhibiting certain forms of the cytochrome P-450 isoenzymes, which would otherwise cause the activation of pre-mutagens and pre-carcinogens.
Additionally, myrcene had a protective role on UVB-induced human skin photo-aging. This is important because it gives evidence that the less toxic myrcene could replace the UV-filter chemicals that are currently being used for sunscreen products.
These studies show support that myrcene can protect the brain, heart, and skin tissues from inflammation and oxidative damage.
Smell profile: pepper, spicy, woody (black pepper, cloves, cinnamon)
Beta-Caryophyllene is unique in that it is a selective full agonist of the CB2 receptor. This gives the terpene a strong anti-inflammatory activity.
Studies in mice show that beta-caryophyllene possesses significant anticancer activities, effecting the growth and proliferation of numerous cancer cells. After analyzing the anti-cancer properties, it is believed the most important function is the ability of beta-caryphyllene to encode proteins for the expression of pro-apoptotic and cancer-suppressing genes. It has also shown to help classic cancer drugs be more effective by increasing the drug concentration inside cells.
Regarding multiple sclerosis, this terpene suppressed neuroinflammation by the up-regulation of interleukin 10 and a reduction in the production of interferon in mice.
In rats with vascular dementia, beta-caryophyllene diminished cognitive deficits and reduced learning and memory deficits.
Recent studies have suggested a protective role of the cannabinoid signaling system in Parkinson's disease. Beta-caryophyllene improved motor function, protected dopaminergic neurons in the substantia nigra and striatum, and diminished glial activation.
Another study reported that this terpene displayed anticonvulsant activity against seizures.
Smell profile: woody, earthy (coriander, basil, hops)
Studies showed that humulene possess anti-inflammatory and anticancer properties. A study a revealed that oral treatment with humulene inhibited a variety of inflammatory factors in mice and rats.
In a study with six different cancer cell lines, humulene decreased the cellular GSH levels and promoted ROS production. This resulted in the inhibition of cancer cell growth. This terpene also induced apoptosis in colorectal cancer cells.
alpha Pinene & beta Pinene
Smell profile: pine (pine needles, dill, basil)
A study reveled that alpha-pinene is very effective in the treatment of metastatic melanoma by its pro-apoptotic and anti-metastatic activity in a mouse model. It was able to reduce the number of lung tumor nodules, likely by caspase-3-induced apoptosis.
In a mouse model, the topical application of alpha-pinene exhibited significant anti-inflammatory and pain relief effects.
Alpha-pinene exhibited anti-inflammatory features in an in vivo model of acute pancreatitis. This terpene reduced the pancreatic weight in relation to body weight.
Inhaled administration has shown anti-anxiety effects. Alpha-pinene directly bonded to GABAA as a partial modulator at the benzodiazepine binding site. Additionally, it was capable of increasing the duration of non-rapid eye movement sleep without affecting the duration of rapid eye movement sleep.
An additional study showed alpha-pinene works as a bronchodilator in humans at low exposure levels and a broad spectrum antibiotic against MRSA.
Beta-pinene revealed antidepressant and sedative activities in mice with several experimental models.
Beta-pinene also shows evidence of exhibiting antiviral activity against the herpes simplex virus.
Smell profile: floral, lavender
Studies conducted on animals and humans suggest linalool exhibits anti-anxiety, mood stabilizing, sedative, pain relief, anti-convulsive, antibacterial, anti-tumor, and neuroprotective properties.
A recent study showed that the protein expression of SIRT3 (which is overactive in several cancers) was significantly inhibited by linalool. This terpene has been found to stop the growth of breast, colorectal, and liver cancer cells. Linalool treatment promoted apoptosis in epithelial ovarian carcinoma cells by increased ROS generation.
A study in rats exhibited that linalool reduced aggressive behavior and improved social interactions. The inhalation of linalool resulted in sedative and anti-anxiety effects in healthy males.
One study evaluated the effects of linalool on aged mice and recorded improved learning and spatial memory of the animals based on behavioral tests.
Smell profile: citrus
In a Phase II clinical trial, limonene induced apoptosis in breast cancer cells.
Limonene restored the levels of reduced GSH, GPx, GSR, and CAT, indicating it may be protective towards healthy cells and tissues. It was found to regulate genes involved in apoptosis, signal transduction, cancer, the expression of kinases, inflammation, DNA damage repair, and cell cycle control. This exhibits its anti-cancer ability through the interplay of theses pathways.
A study showed anti-stress effects in female rats. Limonene was shown to be a motor relaxant and an antidepressant.
Lastly, limonene's derivatives can be powerful anti-convulsants via GABAergic action.
Smell profile: pine, floral, herbal (tea tree, nutmeg, lilacs)
A recent study on the inhalation of terpinolene showed sedative effects in mice.
A study revealed terpinolene prevented LDL-oxidation, which exhibits protective effects that may be beneficial toward combating coronary heart disease and plaque formation in arteries.
Terpinolene has promise to be an anticancer, antioxidant, and anti-inflammatory terpene with efficiency against LDL oxidation and sedative enhancing features.
The above discussed terpenes are a few of the beneficial organic compounds found in Cannabis sativa. Scientific findings have been promising, revealing that terpenes have many health benefits. More scientific research in human trials is absolutely needed. With the studies published, I hope this helps you decide which cannabis strains will help your unique ailments. Many of these terpenes are claimed to promote additional health benefits, but scientific research regarding those benefits is lacking.
I encourage all of you to insist that terpene testing is done on your cannabis products. The more knowledge available to the patient equals more effective treatment. Next time you smell your favorite cannabis strain, train your nose to pick up on these beneficial terpenes. Remember, "your nose knows best".
Nuutinen, Tarmo. “Medicinal Properties of Terpenes Found in Cannabis Sativa and Humulus Lupulus.” European Journal of Medicinal Chemistry , www.deepdyve.com/lp/elsevier/medicinal-properties-of-terpenes-found-in-cannabis-sativa-and-humulus-F7vo58dN4W?articleList=/search?query=terpene cannabis.