PDR for Herbal Medicines

730 /STINGING NETTLE PDR FOR HERBAL MEDICINES

DESCRIPTION

Medicinal Parts: The medicinal parts are the fresh and dried

flowering plant and the roots.

Flower and Fruit: The flowers are greenish-white in axillary,

clustered, hanging panicles. The perigone has 4 tepals. There

are 4 stamens and 1 ovary with a brush-like stigma. The

flowers are dioecious. The male flowers have only stamens

and the female flowers only a style or a seed-producing

organ. The male flower consists of a perianth of 4 segments,

which enclose an even number of stamens. The stamens

curve inward in the bud stage and spring back at the end of

flowering for the anthers to fling out the pollen. The fruit is a

small 1-seeded nutlet.

Leaves, Stem and Root: The plant grows from 60 to 150 cm

high and has a winter hard rhizome. The leaves are opposite,

oblong-cordate and roughly serrate. The whole plant is

covered in stinging hairs.

Habitat: The plant is common in most temperate regions of

the world.

Production: Stinging Nettle herb consists of the fresh or

dried above-ground parts of Urtica dioica, Urtica urens and/

or hybrids of these species, collected during flowering

season. Stinging nettle leaf consists of fresh or dried leaves

of Urtica dioica, Urtica urens and/or hybrids of these species,

gathered during flowering season.

Not to be Confused With: The leaves of Laminum album.

Other Names: Nettle

ACTIONS AND PHARMACOLOGY

COMPOUNDS: STINGING NETTLE FLOWERING PLANT

In the stings of the fresh plant: histamine, serotonin,

acetylcholine, formic acid, leukotriens (LTB4, LTC4, LTD4)

Flavonoids (0.7-1.8%): including rutin, isoquercitrin

(0.02%), astragalin, kaempferol-3-O-rutinoside

Silicic acid (1-4%): partially water-soluble

Volatile oil: chief components are ketones, including, among

others, 2-methylhept-2-en-6-on

Potassium-ions (0.6% in the fresh foliage)

Nitrates (1.5 to 3%)

EFFECTS: STINGING NETTLE FLOWERING PLANT
The fresh leaves contain acetylcholine, serotin and hista-
mine. The pressed juice (main active principles scopoletine,
beta-sitosterol and caffeoyl malic acid) is diuretic in
combination with sufficient fluid intake. In animal experi-
ments, a local anaesthetic and analgesic effect has been
observed. Caffeoyl acid in vitro, inhibits 5-lipoxygenase-

dependent leukotriene synthesis. In various studies, an

antirheumatic and anti-arthritic effect was demonstrated.

Anti-inflammatory Effect - In one study, an extract from

Stinging Nettle leaves (IDS 23) was tested for the ability to

inhibit the biosynthesis of arachidonic acid metabolites in

vitro. IDS 23 showed a strong concentration dependent

inhibition of cyclooxygenase derived reactions. A phenolic

acid isolate from the extract inhibited the synthesis of

leukotriene B4 in a concentration dependent manner. The

authors concluded that the combination of these effects may

account for the antiphlogistic effects of this extract of

Stinging Nettle (Obertreis, 1996.)

COMPOUNDS: STINGING NETTLE ROOT

Steroids: sterols, including beta-sitosterol (0.03 to 0.06%),

beta-sitosterol-3-O-beta-glucoside (0.03 to 0.5%), (6'-Pal-

mitoyl)-sitosterol-3-0-beta-D-glucoside (0.003%), 7alpha-

hydroxysitosterol (0.001%), 7eta-Hydroxysitosterol

(0.001%), stigmasterol, campesterol, stigmast-4-en-3-one

Lectins (0.1%): UDA (Urtica dioica Agglutinin, isolectine

mixture)

Polysaccharides: glucans, glucogalacturonans, acidic arabi-

' nogalactans water-soluble with immunostimulating effect)

Hydroxycoumarins: scopoletin

Lignans: including secoisolariciresinol-9-O-glucoside

(0.004%), neo-olivil (0.003%), neo-olivil-4-O-glucoside

(0.004%)

Ceramides

EFFECTS: STINGING NETTLE ROOT

Effects on Prostate Tissue - The root has been show to cause

an increase in the volume of urine, increase of maximum

urinary flow and reduction of residual urine. One study

found that an aqueous extract of the root was the most

effective in treating benign prostatic hyperplasia. The extract

inhibited the binding of sex hormone-binding globulin

(SHBG) to its receptor on human prostatic membranes in a

dose related manner. Inhibition was noted at 0.6 mg/ml and

complete inhibition was achieved at 10 mg/ml (Hryb et al,

1995.) In a second study, most ligans that were tested were

found to have an affinity for SHBG. The affinity of (-)-3,4-

divanillyltetrahydrofuran was found to be extremely high

(Schottner, 1997.)

Viral Inhibition - The (N-acetylglucosamine) n-specific

lectin fron Stinging Nettle was found to be inhibitory to

HIV-1, HIV-2, CMV, RSV and influenza A virus in-vitro at

an EC-50 (50% inhibitory concentration) ranging from 0.3 to

0.9 micrograms/ml (Balzarini, 1992.)

Effects on Systemic Lupus Erythematosus-like Pathology -

Urtica dioica agglutinin (UDA) treated MRL lpr/lpr mice