Updated: 11 hours ago
This limited-time seasonal article explores the world of terpenes, investigating the more than 20,000 plant species—including cannabis—that produce 40,000 varieties of aromatic terpenes. Roughly 150 of these terpenes are programmed into the cannabis/hemp genome (DNA), a small subset of which (a dozen or so) manifests in an individual cultivar (strain) of the plant.
What is Mistletoe?
Mistletoe is the English common name for a relatively predatory genus of plant for which 1,500 species have been discovered to date. This plant plays a small but significant role in a multitude of cultural celebrations and festivals that date back to the Roman era.
A flowering plant, European varieties of mistletoe produce white and waxy berries in clusters of two to six. The Eastern variety of mistletoe found in North America features shorter, broader leaves than its European sibling and larger clusters of 10 or more berries.
Different varieties of mistletoe are native to several regions of the United Kingdom, Europe, and Africa. Separate species of the plant appear in southwest Spain, southern Portugal, across Great Britain, and in portions of Northern Africa (among other regions). Subtropical and tropical climates feature the largest number of mistletoe species, with Australia sporting 85 species of this peculiar terpene-bearing plant.
"Mistletoe is the English common name for a relatively predatory genus of plant for which 1,500 species have been discovered to date."
Mistletoe is the state flower of Oklahoma and the county flower of Herefordshire, England. The British town of Tenbury Wells holds an annual Tenbury Mistletoe Festival each December during which it showcases the crowning of the exalted “Mistletoe Queen.”
Doorway Hanging Tradition
In the modern Western world, a sprig of mistletoe has become adopted as a winter celebratory decoration under which lovers are expected to kiss—a tradition that is believed to have begun in Germany. The act of kissing under dangling mistletoe is sometimes interpreted as one that affords a cozy couple good luck in terms of the integrity of their future relationship.
In Norse mythology, mistletoe symbolizes love and friendship. During the middle ages, the plant was superstitiously considered protection from evil forces, including demons and witches. By the 18th century, mistletoe had become incorporated into the winter celebrations and traditions of various cultures around the world.
The hanging of mistletoe in doorways, however, began long before the modern Germans. The ancient Romans associated the plant with love, peace, and understanding. The act of hanging mistletoe over a doorway in Rome was believed to channel harmony and compassion and to protect an entire household from harm.
A Parasitic Romance
Mistletoe has been described as a "vicious parasite" of a plant that derives most or all of its nutritional needs from other plants (think of it as a vampire vine). Such plants feature modified roots called haustoria that penetrate the host plant.
A 2019 study entitled "Mistletoe Versus Host Pine: Does Increased Parasite Load Alter the Host Chemical Profile?" that was published in the Journal of Chemical Ecology investigated the molecular composition of both mistletoe and the pine trees that sometimes act as its unwilling hosts.
Mistletoe has been described as a "vicious parasite" of a plant that derives most or all of its nutritional needs from other plants (think of it as a vampire vine).
Reported the researchers, "Our results reveal that, despite the intimate contact between mistletoe and host pine, their chemical profiles differed significantly, revealing extremely low concentrations of defense compounds (including a complete lack of terpenes) in mistletoe leaves." The study's authors continued, "On the other hand, parasitized pines showed unique chemical responses depending on parasite loads. Overall, the monoterpene content increased with parasitism."
"Mistletoe seems to miraculously stay green all winter, and this is 'the fundamental basis of all mid-winter traditions relating to mistletoe,' wrote Jonathan Briggs, a mistletoe expert and consultant, for National Geographic in 2015.
What do Mistletoe & Marijuana Have in Common?
A variety of plants, including mistletoe, conifers, basil, and hemp produce the terpene pinene. This compound is unique in that it is the most common terpene phytomolecule in all of nature. Other plants that manufacture this particular olfactory tickler include dill, hops, orange, parsley, pine, and rosemary. This terpene is also a favorite of the fragrance industry, which employs it in perfumes and a variety of topical products.
Pinene produces a range of aroma, depending on the exact analog form of the molecule being considered. Two analogs, or types, of pinene exist: Alpha-pinene (denoted as α-pinene) and beta-pinene (indicated as β-pinene). The alpha variety conveys an aroma that has been described as light and fresh and that is reminiscent of pine or pine needles. The beta manifestation of this terpene offers a fragrance that is somewhat spicier. The boiling point of the alpha variant is 311-313° F (155-156° C).
Pinene Medicinal Efficacy
Like other terpenes and a variety of cannabinoids, pinene conveys a range of health and wellness benefits, including analgesia (pain management), reductions in inflammation (of benefit to literally hundreds of diseases, including arthritis, fibromyalgia, and multiple sclerosis), and decreased anxiety (helpful to those suffering mood disorders such as clinical depression or Post-traumatic Stress Disorder).
"Like other terpenes and a variety of cannabinoids, pinene conveys a range of health and wellness benefits, reductions in inflammation, and decreased anxiety."
"A variety of interesting pharmacological properties have been attributed to α-pinene, including anti-inflammatory, bronchodilator, hypoglycemic, sedative, antioxidant, and broad-spectrum antibiotic activities," reported 2015 research entitled "Gastroprotective Effect of Alpha-pinene and its Correlation with Antiulcerogenic Activity of Essential Oils Obtained from Hyptis Species."
This terpene is also believed to increase mental focus and alertness. Pinene has also shown promise as a bronchodilator that sometimes aids in respiratory diseases such as asthma.
More than 100 types of cancer afflict nearly two million people each year, with more than half a million patients dying from the disease during the same period. Terpenes such as pinene and cannabinoids like CBD and CBG have demonstrated significant medicinal efficacy against many cancers, as documented by a wide range of clinical research studies and anecdotal reports.
A 2015 study entitled "Phytochemical Profile and Therapeutic Potential of Viscum Album L." that was published in the journal Natural Product Research determined that this particular species of mistletoe produces terpenes that include “triterpenes with cytotoxic and apoptotic [anti-cancer] properties."
Pinene Research Studies
A wealth of peer-reviewed research studies has revealed the nuanced and sometimes striking medicinal efficacy of the terpene pinene. Significant benefits gained from the use of pinene and pinene-rich hemp cultivars and products include anti-cancer mechanisms. Pinene may act as a treatment for viral infections, offers promise as a gastroprotective agent, and sometimes delivers significant reductions in systemic inflammation.
...this particular species of mistletoe produces terpenes that include "triterpenes with cytotoxic and apoptotic [anti-cancer] properties."
A 2018 research study entitled "α-Pinene Inhibits Human Prostate Cancer Growth in a Mouse Xenograft Model" that was published in the journal Chemotherapy investigated the ability of pinene to be employed in the treatment of prostate cancer. "Substantial evidence shows that α-pinene has cancer prevention properties," reported the study's authors.
"We found that treatment with α-pinene significantly inhibited human prostate cancer cell growth," wrote the researchers. They were successful in determining the underlying mechanisms behind this efficacy, which included apoptosis (a genetically programmed mechanism by which cancer cells basically commit suicide) and "cell cycle arrest." The study found that tumor progression was inhibited to a greater extent in mice that were treated with α-pinene than control subjects that received none of this terpene.
The study's authors concluded that pinene may be an effective treatment against prostate cancer. "These data strongly suggest that α-pinene inhibits prostate cancer growth...and may be an effective therapeutic agent for prostate cancer treatment."
A 2016 study entitled "a-Pinene, a Major Constituent of Pine Tree Oils, Enhances Non-Rapid Eye Movement Sleep in Mice" that was published in the journal Molecular Pharmacology explored the ability of pinene to reduce anxiety and potentially act as a sleep aid.
"The study's authors concluded that pinene may be an effective treatment against prostate cancer."
The researchers reported that pinene may be helpful in treating a variety of anxiety and sleep disorders. "a-Pinene also decreased sleep latency and increased sleep duration in a dose-dependent manner," reported the study, adding that "administration of 100 mg/kg of a-pinene was found to prolong sleep duration."
A 2015 study entitled "Gastroprotective Effect of Alpha-pinene and its Correlation with Antiulcerogenic Activity of Essential Oils Obtained from Hyptis Species" that was published in the journal Pharmacognosy Magazine "investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer...in mice."
The researchers observed positive efficacy between use of pinene and the treatment of gastrointestinal conditions. "α-pinene pretreatment inhibited...gastric lesions, reduced [the] volume and acidity of gastric juice, and increased gastric wall mucus." The study noted a correlation between "concentration of α-pinene and gastroprotective effect," indicating the importance of dosing (titration) in any treatment regimen.
A 2015 study entitled "Anti-tumor Effect of α-pinene on Human Hepatoma Cell Lines" that was published in the Journal of Pharmacological Sciences explored the ability of pinene to exhibit anti-cancer activity.
"The researchers observed positive efficacy between use of pinene and the treatment of gastrointestinal conditions."
"The α-pinene is a natural compound isolated from pine needle oil which has shown anti-cancer activity," wrote the researchers in their preface to the research report. The study's authors noted how a previous study that they conducted revealed that pinene "exhibited significant inhibitory effect on hepatoma carcinoma cells."
The research explained how α-pinene displayed an inhibitory effect on cancer cell growth "in a dose- and time-dependent manner." It found the cell growth inhibitory rate to be 79% when α-pinene was applied at a concentration of eight (8) mg/L for 72 hours. "The result suggests that α-pinene can effectively inhibits cell growth," concluded the study’s authors.
A 2014 study entitled "Anti-inflammatory and Chondroprotective Activity of α-pinene" that was published in the Journal of Natural Products investigated the anti-inflammatory capabilities of pinene in the treatment of osteoarthritis. "Previous studies have suggested that α-pinene, a common volatile plant metabolite, may have anti-inflammatory effects in human chondrocytes, thus exhibiting potential antiosteoarthritic activity," reported the study’s authors.
"Studies have suggested that α-pinene may have anti-inflammatory effects in human chondrocytes, thus exhibiting potential antiosteoarthritic activity."
Concluded the study, "The data obtained show...anti-inflammatory and anticatabolic effects of α-pinene in human chondrocytes." The researchers found α-pinene to be "promising for further studies to determine its potential value as an antiosteoarthritic drug."
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