MIDDLE EAST RESPIRATORY SYNDROME CORONAVIRUS—OR JUST “CORONAVIRUS” AS IT HAS BEEN DUBBED IN THE MEDIA—IS AN EMERGING VIRAL PATHOGEN THAT CAUSES SEVERE MORBIDITY AND MORTALITY. ACCORDING TO THE CDC, “THERE IS CURRENTLY NO VACCINE TO PREVENT CORONAVIRUS DISEASE.”1 TO PREVENT ITS TRANSMISSION, THE CDC RECOMMENDS EVERYDAY PREVENTIVE ACTIONS TO HELP PREVENT THE SPREAD OF ANY RESPIRATORY DISEASE:
- Avoid close contact with people who are sick.
- Avoid touching your eyes, nose, and mouth.
- Stay home when you are sick.
- Cover your cough or sneeze with a tissue, then throw the tissue in the trash.
- Clean and disinfect frequently touched objects and surfaces using a regular household cleaning spray or wipe.
Naturally these are good recommendations, but shouldn’t there be something else we can do to help prevent the transmission of coronavirus? In my opinion, there is. Let’s start with resveratrol.
Resveratrol and the coronavirus
In 2006 an in-vitro study2 was undertaken in China to examine
the effects of “stilbene derivatives” to inhibit coronavirus
replication. What are stilbene derivatives? They are an
important family of bioactive molecules that are normally
associated with plants. Stilbenes are produced in response to
injury or attack by pathogens.3,4 The most extensively studied
stilbene is resveratrol. In any case, the 2006 study found that
various stilbene compounds were able to inhibit coronavirus
replication. This may have included resveratrol, but the study
details made it somewhat difficult to determine.
Then, in 2017, another in-vitro study5 was conducted to
specifically examine the antiviral effect of resveratrol against
coronavirus. In this study, cells from coronavirus infected
patients were given resveratrol. The results were that resveratrol
significantly inhibited coronavirus infection and prolonged
cellular survival after virus infection. In addition, resveratrol
decreased the replication of nucleocapsid, a protein essential
for coronavirus replication. Furthermore, resveratrol down-regulated
apoptosis (i.e. cellular death) induced by coronavirus.
This study clearly demonstrated that resveratrol is a potent anticoronavirus
agent in-vitro. The study’s authors suggested that
resveratrol can be a potential antiviral agent against coronavirus
in the near future.
Resveratrol and the immune system
So why was resveratrol effective against coronavirus? Although
we can’t say for certain, we do know that resveratrol can increase
certain circulating immune cells known as gamma delta T
cells. Human research6 was conducted to assess the effects
of repeated doses of resveratrol (1000 mg/day for 28 days) on
circulating immune cells in healthy individuals. The results were
that resveratrol was safe and well tolerated and was associated
with significant increases in the numbers of circulating gamma
delta T cells (functioning as a first line of defense and a bridge
between innate and adaptive responses) and regulatory T cells.
Now consider that analyses of T cell repertoires in health
care workers who survived coronavirus infection during the 2003
outbreak revealed that their gamma delta T cell populations
were selectively expanded about 3 months after the onset of
disease. The expansion of the gamma delta T cell population
was associated with higher production of anti-coronavirus
immunoglobulin G titers. In addition, in-vitro experiments
demonstrated that stimulated gamma delta T cells display an
interferon- gamma -dependent anti-coronavirus activity and
are able to directly kill coronavirus-infected target cells. These
findings suggest that gamma delta T cells play a protective role
during coronavirus7—and resveratrol increases the numbers of
circulating gamma delta T cells.
So, pending human clinical trials on the effects of resveratrol
against coronavirus, what is a good dose of resveratrol to be
used for protective effects? My suggestion is to use 1,000 mg
of resveratrol daily, which is consistent with the amount used in
human clinical research in which delta T cells were effectively
Black elderberry protection
In addition to resveratrol, black elderberry may also offer a
degree of protection against coronavirus—although it has yet
to be tested for this purpose. My rationale for this is based upon
black elderberry’s success in treating influenza.
The flu virus invades cells by puncturing their walls with
tiny spikes called hemagglutinin that cover its surface. In-vitro
research found that natural components of black elderberry
(Sambucus nigra) actually disarm the spikes. It binds to them,
thus preventing them from piercing the cell membrane. The
viral spikes are covered with an enzyme called neuraminidase.
This enzyme acts to break down the cell wall.
To test how black elderberry would work in actual people
with the flu, a team of Israeli scientists and physicians conducted
placebo-controlled, double blind study on patients infected
with the flu virus during an epidemic in Southern Israel. The
results were that within twenty-four hours the symptoms—
fever, cough, and muscle pain had significantly improved in
twenty percent of the patients. After the second day, another
seventy five percent were clearly much improved, and in three
days a complete cure was achieved in over ninety percent of the
patients studied. Among the control group only eight percent
of patients showed an improvement after 24 hours, and for
the remaining 92 percent, improvement was observed within
six days or more. Tests were also conducted on patients to
determine the presence of influenza antibodies. It was found that the level of antibodies was higher in patients receiving
the black elderberry extract versus those receiving the placebo,
indicating an enhanced defense response in those patients.8
Other research9 has also shown that a black elderberry
extract effectively treated and helped relieve symptoms of
influenza when taken in doses of 175 mg four times daily.
So, what’s the relationship to coronavirus? Just this:
hemagglutinin is also found on the surface of coronavirus.
In fact, coronavirus may have actually evolved from a certain
type of influenza.10 Consequently, it’s not much of a stretch to
imagine that black elderberry may also have application against
coronavirus. Pending human clinical trials on the effects of
black elderberry against coronavirus, my suggestion is to use
175 mg of black elderberry extract daily, as a prophylactic dose
rather than a treatment for actual coronavirus.
Currently there are no vaccines to prevent coronavirus. However,
research suggests that 1000 mg of resveratrol daily, and 175 mg
of black elderberry extract may have a protective effect against
the coronavirus. Until such time as other proven prevention
methods come to fruition, it seems prudent to consider the
regular use of these nutraceuticals.