Aristolochia indica

English: Indian birthwort
Hindi: Isharmul
Sanskrit: Sunanda

The plant is commonly known by the names birthwort and snakeroot, which refer to its use in traditional medicine for postpartum infections and snakebite respectively. These indications may have originated in the medieval Doctrine of Signatures, which believed that the appearance of a plant pointed to its purpose. The flowers of Aristolochia were thought to resemble a curved foetus or a snake. The Hindi name iswari suggests that the plant has the property of neutralising snake poison. Unfortunately, aristolochic acid, one of the major constituents, is now known to be too toxic for the plant to be used in human medicine. It is included only for information.

Habitat

The plant is distributed throughout all the provinces of India and in Sri Lanka, Nepal and Bangladesh. It is usually found scrambling over hedges and bushes.

Botanical description

Leaves simple, alternate, short petioled, the blade ovate or somewhat wedge shaped, very variable in shape and size (Plate 8). The young leaves are light purplish. The fruit is a capsule, roundish or oblong and hexagonal, 2.5-4 cm long and slightly less broad, with shallow grooves and six valves, containing many triangular seeds. The young roots are light brown and fairly smooth, whereas the older ones are comparatively rough due to the development of cork, lenticels and the presence of scars of rootlets. The cork layer somewhat friable. In a freshly cut transverse section of the root the entire bark appears as a narrow, cream-coloured strip, surrounding! a wide woody core. The wood has a light yellow colour and appears highly porous, with the pores being sufficiently large to be easily visible with the naked eye; the medullary rays are soft and creamy white in colour; there is no pith in the centre.

Parts used

Roots, rhizomes and leaves.

Traditional and modern use

The plant has been used in skin diseases where there is morbidity of vata, pitta and kapha. It is used as a appetiser, aphrodisiac and anthelmintic. The fresh juice of the leaves is a popular antidote to snake poison. The leaves and bark are used in bowel complaints of children, diarrhoea and in intermittent fevers. In traditional medicine the underground parts of the plant are rubbed with honey and given to treat leprosy; and, macerated with black pepper, it is prescribed in diarrhoea.

Ethnoveterinary usage

The root and stem of the plant are used in aches and pains, rheumatism, anthrax, madness and snakebite.

Major chemical constituents
Phenanthrene derivatives

Aristolochic acid aristolochic acid-D, aristolochic acid-D methyl ether lactam, aristololactam β-D-glucoside/ aristolic acid, aristolic acid methyl ester, methyl aristolochate, aristolamide, aristolinic acid, aristolonitrite.

Quinones

Aristolindiquinone.

Lactones

Aristololide.

Sesquiterpenes

(12S)- 7, 12-Secoishwaran -12-01,6 ishwarol, 7 ishwarone, ishwarane, aristolochene,9 ishwarene, selina-4(14),11-diene,1O ledo1.

Alkaloid

Aristolochine.

Terpenes

The essential oil of the aerial parts contains mono- and sesquiterpenes including linalool, β-caryophyllene, a-humulene, ishwarone, caryophyllene oxide, ishwarol, ishwarane and aristolochene, and a-terpinolene.

Others

Ceryl alcohol, allantoin, p-coumaric acid/o d-camphor,15 sitosterol and stigmast-4-en-3-one.

Medicinal and pharmacological activities

General antifertility activity: Aristolic acid, from Aristolochia indica, disrupted nidation in mice when administered on day 1 of pregnancy. The implantation-inhibiting effect of the compound was assessed with respect to tubal transport of ova into the uterus, hyperpermeability of endometrial capillaries, increase in uterine weight and total protein content, endometrial bed preparation and changes in uterine phosphatase enzymes during days 4-6 of pregnancy. The plant induces impairment of development, with a decrease in uterine weight and total protein content, in treated animals. Aristolic acid interfered with steroidal conditioning of the uterus, rendering it hostile to ovum implantation. An ethanol extract of A. indica root was found to decrease fertility in both rats and hamsters when administered postcoitally (on days 1-10 and 1-6 respectively). Methyl aristolate (60 mg/kg, orally) decreased the number of implantation sites when administered on the first two days of pregnancy in mice. When given at doses of 50 mg/kg (but not at 30 mg/kg) consecutively on days 1-4 of pregnancy, the number of implantation sites was also decreased, possibly by disturbing the hormone balance and thereby disrupting implantation. The aqueous alcoholic and petroleum ether extracts of Aristolochia indica at 1 :20 concentration affected the oestrus cycle adversely, terminating at the dioestrous stage. These extracts also showed a marked reduction in RNA, sialic acid, glycogen of the uterus and vagina, and ascorbic acid of the adrenal glands. An aqueous alcoholic extract (at 0.2 ml) was found to be more effective than the petroleum ether extract.

Antioestrogenic activity: Aristolic acid exhibited antioestrogenic activity as shown by the prevention of oestrogen-induced weight increase and epithelial growth in the mouse uterus. It caused a decrease in alkaline phosphatase activity, glycogen content and mitotic counts in the oestrogen-treated uterus and prevented implantation in the early stages of pregnancy in mice.

Abortifacient activity: In female mice, methyl aristolate produced 100% abortifacient activity at a single oral dose of 60 mg/kg when administered on the sixth or seventh day of pregnancy and 20-25% when given on days 10 or 12, respectively.

Interceptive activity: Fractions isolated from the chloroform extract of Aristolochia indica at doses of 35-60 mg/kg demonstrated interceptive activity. Histological studies of the uterus and ovary at the minimum effective dose levels with each fraction revealed no overt changes apart from the presence of degenerated corpora lute a in the ovary of the animals treated, and no teratogenic effects were observed. A
sesquiterpene isolated from the roots demonstrated 100% interceptive activity and 91.7% antiimplantation activity in mice at a single oral dose of 100 mg/kg, with no other toxic effects at the dose levels used. p- coumaric acid isolated from Aristolochia indica also showed 100% interceptive activity when administered at 50 mg/kg to mice, with a high margin of safety (> 1 000 mg/kg) and no teratogenic activity.

Antitumour activity: Aristolochic acid was found to have activity against adenocarcinoma 755 in mice.

Immunomodulatory activity: Aristolochic t acid has been shown to bind to surface f receptors of lymphocytes, altering immune t response.24 An immune-stimulating action was reported in a human study which measured ,increased  phagocytic activity after 3 days of treatment at a dosage of 0.9 mg/day.

Anti-inflammatory activity: Aristolochic acid also played a regulatory role in prostaglandin synthesis. It inhibited inflammation by both immunological and non-immunological agents. One mechanism of activity was thought to be as a direct inhibitor of phospholipase A2, decreasing the generation of eicosanoids and platelet-activating factors. Another anti-inflammatory mechanism may be the effect on arachidonic acid mobilisation in human neutrophils.

Safety profile

The plant is carcinogenic and nephrotoxic." The LD50 value of the 50% alcoholic extract of the whole plant, when administered to mice, was 375 mglkg. Its usage is not recommended.

Dosage

• Root powder: 1-3 g Leaf infusion: 5-10 ml

Ayurvedic properties

• Guna: Laghu (light), ruksha (dry) Rasa: Katu (bitter), kasaya (astringent) Veerya: Ushna (hot)
• Vipaka: Katu (bitter)
• Dosha: Balances kapha and vata