Common names: Thorowax, Saiko,
Hare’s ear, Chai
hu
These
Asian plants are part of the Apiaceae
(Umbelliferae) family, and resemble dill or fennel.
However, bupleurum has long thin leaves rather than the
lacy appearance of fennel and dill leaves. The Chinese
name for bupleurum, chai hu, means “kindling of
the barbarians.” The origin of this name is unclear. The
roots of the plant are used in herbal
medicine.
Historical
or traditional use
Bupleurum has been used in Traditional
Chinese Medicine for thousands of years to help relieve
numerous conditions. Most particularly, infections with
fever, liver problems, indigestion, hemorrhoids, and
uterine prolapse.
Bupleurum is a key ingredient in the
formula known as sho-saiko-to. This is a Japanese kampo
or traditional herbal medicine formula based on the
traditional Chinese formula xiao-chai-hu-tang. In
English, it has been called minor bupleurum formula.
Bupleurum makes up 16% of the formula for sho-saiko-to
(see below for the complete contents of the formula).
Results reported for sho-saiko-to cannot be attributed
solely to bupleurum because the other herbs in the
formula also contribute.
Sho-saiko-to (xao-chai-hu-tang or minor
bupleurum formula) contains the
following:
- Bupleurum falcatum
(thorowax) root, 16%
- Paeonia lactiflora
(peony) root, 16%
- Pinellia ternata (ban
xia) rhizome, 14%
- Cinnamomum cassia
(cassia) bark, 11%
- Zingiber officinale
(ginger) rhizome, 11%
- Zizyphus jujuba
(jujube) fruit, 11%
- Panax ginseng (Asian
ginseng) root, 8%
- Scutellaria baicalensis
(Chinese scullcap) root, 8%
- Glycyrrhiza uralensis
(licorice, gan cao) rhizome,
5%
Active
constituents
Bupleurum contains constituents known as
saikosaponins that appear to account for much of the
medicinal activity of the plant. Test tube studies have
shown that the sho-saiko-to combination can increase
production of various chemicals (known as cytokines)
that immune cells use to signal one another. Test tube
studies have also found that saikosaponins can inhibit
growth of liver cancer cells, and are
anti-inflammatory.
Human
trials, only one double-blind, have shown that the
bupleurum-containing formula sho-saiko-to may help
reduce symptoms and blood liver enzyme levels in
children and adults with chronic active viral hepatitis
Most of these studies were in people with hepatitis B
infection, though one preliminary human trial has also
shown a benefit in people with hepatitis C. Sho-saiko-to
was also found, in a large, preliminary (but not
double-blind), study to decrease the risk of people with
chronic viral hepatitis developing liver cancer.
Sho-saiko-to has also been used to reduce
symptoms of and possibly decrease the severity of liver
cirrhosis though clinical studies on this condition are
generally lacking. One randomized trial (it was unclear
if this trial was double-blind) found that sho-saiko-to
could reduce the rate of liver cancer in people with
liver cirrhosis.
Several uncontrolled trials in Japan have
shown that sho-saiko-to or very similar traditional
Japanese and Chinese herbal formulas (all containing
bupleurum) can reduce seizure frequency and/or severity
in people with epilepsy that does not respond to
anti-seizure medications.However, double-blind trials
are still needed to determine the importance of these
findings.
Sho-saiko-to has been found to inhibit
human immunodeficiency virus (HIV) in the test tube.
Yet, it is unclear to what degree bupleurum or
saikosaponins contributed to this effect. Sho-saiko-to
also increased the efficacy of the standard anti-HIV
drug lamivudine in the test tube. Human data are lacking
on the benefit of sho-saiko-to or bupleurum in people
with HIV infection or acquired immunodeficiency syndrome
(AIDS).
