NIS - libdoc.who.int - World Health Organization

WHO monographs on medicinal plants commonly used in the Newly Independent States (NIS)
Cardiovascular effects
Following intragastric administration of an ethanol-aqueous extract (1:1)
of fresh leaves to rats, hypotensive activity, negative chronotropic effect
and diuretic activity were observed. The concentration of the extract was
roughly equivalent to 5 g fresh leaf material/kg body weight (bw) of the
animal (results were significant at p < 0.05) (85, 86).
Antihyperglycaemic activity
The antihyperglycaemic (antidiabetic) activity of an aqueous-ethanol extract
of the dried leaves was studied in healthy male mice and in male mice
with alloxan-induced diabetes. The extract significantly reduced the
blood glucose concentration of fasting normal mice 120 minutes (15.7%)
and 240 minutes (30.2%) after intraperitoneal administration (p < 0.05).
The extract also significantly diminished the hyperglycaemia in mildly
diabetic mice after 240 minutes (22.7%). The administration of the extract
to animals with severe hyperglycaemia did not cause a significant decrease
in blood glucose concentration (87). A dried methanol extract of the
leaves of S. officinalis (100, 250, 400 and 500 mg/kg) was injected intraperitoneally
to rats with streptozocin-induced diabetes. Blood samples
were obtained before and after administration of the extract. The results
showed that the extract decreased serum glucose in diabetic rats in 3 hours
with no effect on insulin release from the pancreas. This effect was not
seen in normal rats (83).
Antimutagenic activity
The antimutagenic activity of a terpenoid fraction of the dried leaves was
tested in Escherichia coli strain K12 in vitro. At a concentration of 20 µg/
ml, the terpenoid fraction demonstrated antimutagenic activity against
ultraviolet-induced reversion of argE 3 ochre mutations (88). Acetone,
ethyl acetate, methylene dichloride and hexane extracts of the dried
leaves also expressed antimutagenic effects in vitro (concentration 10 µg/
ml) in Salmonella typhimurium strain TA98 against 3-amino-1-methyl-
5H-pyrido[4,3-b]indole-induced mutagenesis (89). The antimutagenic
properties of terpenoid fractions of S. officinalis leaves were tested in a
mammalian system in vivo by examining the ability of the plant extracts
to decrease the frequency of aberrant cells induced by a potent mutagen.
Groups of mice were treated with three concentrations of terpenoid
fractions. There was no significant difference between the frequency of
aberrant cells after treatment with a concentration of 25 µl/kg and after
treatment with the negative control (olive oil). However, at a concentration
of 50 µl/kg, the frequency of aberrant cells was significantly de-
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