Scientists discover further infection-fighting properties of Chios mastic gum
Chios mastic gum (CMG) is an aromatic resin produced from the mastic tree, Pistacia lentiscus var. Chia, which is mainly grown on the island of Chios, Greece. It has been used as a natural remedy for stomach and intestinal disorders for more than 2500 years.
In recent decades, the health-promoting properties of CMG have been confirmed in clinical studies, which have shown that this natural product exerts antioxidant, anti-inflammatory, antimicrobial, antidiabetic, and antiatherogenic properties in humans. Moreover, clinical trials have shown that CMG has distinct benefits for gastrointestinal and oral health, as discussed in more detail below.
The potential antiviral effects of CMG have not been explored, however, until now: A 2021 study published in the peer-reviewed Journal of General Virology has shown that CMG can inhibit influenza virus replication in human cells and animal models alike. The authors suggest that CMG could be used as a novel therapeutic agent to fight influenza, and that it may have applications for other viral infections as well.
Chios mastic gum inhibits influenza virus
CMG substantially reduced the production of infectious virus particles as compared to untreated controls. This led to an 80% decrease in viral titers in cells that were exposed to IAV, a highly significant result.
Influenza, or flu, is a respiratory tract infection caused by influenza A, B and C viruses, which infect the nose, throat and lungs. Annual influenza epidemics are responsible for about one billion infections, up to five million cases of severe illness, and more than 600,000 deaths worldwide.
Because CMG is known to modulate biochemical processes involved in cell survival, the authors of the 2021 study speculated that viral replication – which is largely dependent on host cell processes – might be influenced by CMG. They showed that exposure of human cells with influenza A virus (IAV) triggered the death of a significant number of cells, but that the addition of CMG to the culture medium reduced the incidence of cell death by fourfold. The results indicate that CMG can substantially protect host cells from the cytotoxic effects of IAV.
Importantly, CMG substantially reduced the production of infectious virus particles as compared to untreated controls. This led to an 80% decrease in viral titers in cells that were exposed to IAV, a highly significant result.
The authors also investigated the mechanism of the antiviral effect through a series of experiments. Specifically, they showed that CMG interferes with the mechanism by which IAV gains entry to the interior of human cells. As a therapeutic class, viral entry inhibitors are extremely efficient in ameliorating viral infections, as the entry of the virus is the first step of infection.
The potent effects of CMG in living cells led the authors to test whether CMG also exhibits antiviral activity in an animal model of infection. They treated mice intranasally with CMG, and then exposed them to IAV. The lungs of the mice pretreated with CMG had significantly reduced viral titers as compared to the lungs of the control mice. Whereas all control mice succumbed to the IAV infection by 11 days post-infection, 80% of the CMG-treated mice survived. Taken together, these results suggest that CMG reduces viral propagation in the lungs, which protects mice from IAV-induced morbidity and mortality.
CMG’s ability to ameliorate influenza infections in mice has major implications for the development of novel therapeutics for humans. Moreover, other studies suggest that the antiviral properties of CMG are not limited to influenza. A study published in 2020, for example, found that components of mastic gum were capable of inhibiting herpes simplex virus-2 (HSV-2), a sexually-transmitted virus that causes genital herpes.
CMG supports gastrointestinal and oral health
The active ingredients in CMG may help inhibit both dental cavities and gum disease.
The evergreen shrub from which CMG is derived – Pistacia lentiscus – is rich in terpenes, a known class of medicinal compounds. The major constituents of CMG include alpha- and beta-pinene, caryophyllene, limonene, and myrcene.,, Studies have shown that these ingredients are bioavailable, meaning that oral administration of the gum or essential oil raises one’s blood levels of these substances.,
CMG has antimicrobial activity against Helicobacter pylori (H. pylori), the bacterium responsible for causes of some peptic (stomach) ulcers and certain types of stomach cancer.,, It also has antimicrobial activity against Porphyromonas gingivalis, a bacterium associated with periodontal disease, and Streptococcus mutans,,, a bacterium that promotes the development of dental caries (cavities). With respect to S. mutans, CMG was nearly as effective as chlorhexidine, the active ingredient of many antibacterial mouthwashes.
Consistent with these findings, a placebo-controlled clinical study of dental students showed that the total number of bacteria in saliva was significantly reduced during four hours of chewing mastic gum compared to a placebo gum. In other studies, mastic oil (prepared from mastic gum) was shown not only to inhibit S. mutans growth in vitro, but also to reduce the ability of S. mutans to adhere to surfaces. Bacterial adhesion to the surfaces of teeth is the first step in the formation of dental plaque, which contributes to tooth decay. Taken together, studies suggest that the active ingredients in CMG may help inhibit both dental cavities and gum disease.
Anti-inflammatory and antioxidant properties of CMG
Mastic gum and its constituents have been shown to protect healthy cells from harm under conditions of oxidative stress.
Mastic gum and its constituents have been shown to protect healthy cells from harm under conditions of oxidative stress., CMG exerts these cell-protective properties by modulating cell signaling pathways, including the Nrf2 pathway., Treatment of human cells with either mastic oil, myrcene, or alpha-pinene has been shown to upregulate Nrf2 within human cells.
The Nrf2 pathway regulates genes that control antioxidant production, detoxification, and cell survival in response to injury and inflammation., Regarding inflammation, a placebo-controlled study of adults with inflammatory bowel disease showed a significant reduction in plasma levels of inflammatory markers in the group receiving CMG (6 capsules daily, with each capsule containing 370 mg CMG.)
CMG can also improve various metabolic functions, even in healthy adults. In one study, there was a reduction in blood cholesterol and liver enzyme levels in the group consuming CMG as compared with a control group., In another study, the daily use of CMG for six months significantly reduced serum triglyceride and insulin concentrations.
In sum, CMG has great potential as a supplement to support health throughout the body, and it may help protect against both viral and bacterial infections. Clearly, we are just beginning to understand the many medicinal benefits of this amazing plant that the Greeks have known for so many years.Click here to see References
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