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Indian Journal of Medical Sciences, Volume 57, Number 9, September 2003, pp. 408-414 ASPARAGUS RACEMOSUS - AN UPDATE R K Goyal, J Singh,* Harbans Lal** Lecturer in Pharmacy; *Reader in Pharmacology; **Professor in
Biochemistry, Pt. B. D. Sharma Post Graduate Institute of Medical Science,
Rohtak, Haryana, Accepted Date: 17-07-2003. Code Number: ms03025 ABSTRACT Asparagus racemosus (Shatavari) is recommended in Ayurvedic texts for prevention and treatment of gastric ulcers, dyspepsia and as a galactogogue. A. racemosus has also been used successfully by some Ayurvedic practitioners for nervous disorders, inflammation, liver diseases and certain infectious diseases. However, no scientific proof justifying aforementioned uses of root extract of A. racemosus is available so far. Recently few reports are available demonstrating beneficial effects of alcoholic and water extracts of the root of A. racemosus in some clinical conditions and experimentally induced diseases, e.g. galactogogue effect, antihepatotoxic and immunomodulatory activities. The present article includes the detailed exploration of pharmacological properties of the root extract of A. racemosus reported so far. INTRODUCTION The genus Asparagus has been recently moved from the subfamily Asparagae in the family Liliaceae to a newly created family Asparagaceae. The Asparagus genus is considered to be of medicinal importance because of the presence of steroidal saponins and sapogenins in various parts of the plant.1 Asparagus is the Greek word for "stalk" or "shoot". About 300 species of Asparagus are known to occur in the world. Some of the European species to be mentioned are A. officinalis, A. sprengeri and A. acutifolius. A. officinalis is reported to be a popular vegetable consumed in many parts of the world.2 Out of several species of `Asparagus' grown in India, A. racemosus, A. gonaclades and A. adsendens are most commonly used in indigenous medicine.3 A. racemosus is commonly mentioned as a rasayana in the Ayurveda. Rasayanas are those plant drugs which promote general well being of an individual by increasing cellular vitality or resistance. A study of ancient classical Ayurvedic literature claimed several therapeutic attributes for the root of A. racemosus (Hindi:-Shatavari) and has been specially recommended in cases of threatened abortion and as a galactogogue.4 Root of A. racemosus has been referred as bitter-sweet, emollient, cooling, nervine tonic, constipating, galactogogue, aphrodisiac, diuretic, rejuvenating, carminative, stomachic, antiseptic5 and as tonic. Beneficial effects of the root of A. recemosus are suggested in nervous disorders, dyspepsia, diarrhoea, dysentry, tumors, inflammations, hyperdipsia, neuropathy, hepatopathy,6 cough, bronchitis, hyperacidity and certain infectious diseases. However no scientific proof, justifying all the above uses of the root of A. racemosus is available so far. This review describes various pharmacological properties of the root extract of A. racemosus evaluated/reported so far (Table 1). Gastrointestinal effects The powdered dried root of A. racemosus is used in Ayurveda for dyspepsia. Oral administration of powdered dried root of A. racemosus has been found to promote gastric emptying in healthy volunteers. Its action is reported to be comparable with that of the synthetic dopamine antagonist metoclopromide.7 In Ayurveda, A. racemosus has also been mentioned for the treatment of ulcerative disorders of stomach and Parinama Sula, a clinical entity akin to the duodenal ulcer diseases. The juice of fresh root of A. racemosus has been shown to have definite curative effect in patients of duodenal ulcers.8 A. racemosus along with Terminalia chebula reported to protect gastric mucosa against pentagastrin and carbachol induced ulcers, by significantly reducing both severity of ulceration and ulcer index.9 Decreased volume and increased pH of the secretions in drug treated rats suggest a reduced responsiveness of the gastric parietal cells to secretogogues and narcotizing agents.9 Cytoprotective effect has been suggested to be due to increased output of mucus. Singh et al10 showed that Shatavari promptly and persistently relieve the pain and burning sensation as well as other dyspeptic symptoms due to duodenal ulcer. Since Shatavari did not have antacid and anti-secretory properties, the observed mild reduction in acid secretion may be due to some changes in gastric mucosa. Shatavari has been suggested to heal the ulcers by potentiating defensive factors and many hypothesis have been put forward for its possible mechanism10: Other possible mechanism may be deactivation and binding of pepsin or of bile salts. In addition to antiulcerogenic activity of A. racemosus in clinical trials, De et al11 demonstrated similar effects of fresh root juice of A. racemosus in rats, using cold stress and pyloric-ligation induced gastric ulcer. In contrast to previous report10 these workers suggested a reduction in acid and pepsin contents (aggressive factors) and increase in mucin-bicarbonate secretions and life span of the mucosal cells (defensive factors). Anti-ulcerogenic effect is suggested to be due to the regulation of the above two factors.12 Various extracts from the root of A. racemosus have been shown to cause contraction of smooth muscles of rabbit's duodenum, guinea pig's ileum and rat's fundal strip without affecting peristaltic movement. These actions were found to be similar to that of acetylcholine and were blocked by atropine, suggesting a cholinergic mechanism of action.13 However, no effect was observed on isolated rectus abdominus. Galactogogue effect The root extract of A. racemosus is prescribed in Ayurveda to increase milk secretion during lactation.4 A. racemosus in combination with other herbal substances in the form of `Ricalex' tablets (Aphali pharmaceutical Ltd. Ahmednagar) has been shown to increase milk production in females complaining of deficient milk secretion.14 Gradual decrease in milk secretion, on withdrawl of the drug suggested that the increase in milk secretion was due to drug therapy only and not due to any psychological effect. Systemic administration of the alcoholic extract of A. racemosus in weaning rats increased weight of the mammary glands, inhibited involution of lobulo-alveolar tissue and maintained milk secretion.15 The same extract in estrogen-primed rats showed well developed lobulo-alveolar tissue and lactation. Increase in mammary gland weight and growth of the lobulo-alveolar tissue may be due to the action of released corticoids and prolactin.16 In an another study, A. racemosus alongwith some other herbal substances in the form of a commercial preparation, lactare (TTK Pharma, Chennai) is reported to enhance milk output in women complaining of scanty breast milk, on 5th day after delivery.17 A significant increase in milk yield has also been observed in guinea pigs and goats after feeding lactare which also increased growth of the mammary glands, alveolar tissues and acini in guinea pigs.18 Patel et al19 have also shown galactogogue effect of roots of A. racemosus in buffaloes. However, Sharma et al20 did not observe any increase in prolactin levels in females complaining of secondary lactational failure with A. racemosus suggesting that it has no lactogenic effect. Effects on uterus Inspite of cholinergic activity of A. racemosus on guinea pig's ileum, ethyl acetate and acetone extracts of the root of A. racemosus blocked spontaneous motility of the virgin rat's uterus.13 These extracts also inhibited contraction, induced by spasmogens like acetylcholine, barium chloride and 5-hydroxytryptamine whereas alcoholic extract was found to produce a specific block of pitocin induced contractions. On the other hand petroleum ether as well as ether extracts of the powdered roots did not produce any uterine activity. It indicates the presence of some particular substance in the alcoholic extract which specifically blocks pitocin sensitive receptors though not other receptors in the uterus,13 confirming that Shatavari can be used as uterine sedative. Further, a glycoside, Shatavarin I, isolated from the root of A. racemosus has been found to be responsible for the competitive block of oxytocin-induced contraction of rat, guinea pig and rabbit's uteri, in vitro as well as in vivo.21 Immunomodulatory activities Intra-abdominal sepsis are major causes of mortality following trauma and bowel surgery. Immunomodulating property of A. racemosus has been shown to protect the rat and mice against experimental induced abdominal sepsis.22,23 Oral administration of decoction of powdered root of A. racemosus has been reported to produce leucocytosis and predominant neutrophilia along with enhanced phagocytic activity of the macrophages and polymorphs. Percentage mortality of A. racemosus treated animals was found to be significantly reduced while survival rate was comparable to that of the group treated with a combination of metronidazole and gentamicin.22,23 Since A. racemosus is reported to be devoid of antibacterial action, so protection offered by A. racemosus against sepsis by altering function of macrophages, indicates its possible immunomodulatory property.22 Further, oral administration of total extract of A. racemosus has been shown to reduce all the three attributes of adhesions viz number, character and area markedly in an animal model of intraperitoneal adhesions.24 Dhuley25 has reported the revival of macrophage chemotaxis and interleukin-I (IL-I) and tumor necrosis factor a(TNFa) production by the oral treatment of A. racemosus root extract in ochratoxin A treated mice. Alcoholic extract has been found to enhance both, humoral and cell mediated immunity of albino mice injected with sheep red blood cells as particulate antigen.26 Antihepatotoxic activity Alcoholic extract of root of A. racemosus has been shown to significantly reduce the enhanced levels of alanine transaminase, aspartate transaminase and alkaline phosphatase in CC14-induced hepatic damage in rats,26 indicating antihepatotoxic potential of A. racemosus. Antineoplastic activity Chloroform/methanol (1:1) extract of fresh root of A. racemosus has been reported to reduce the tumor incidence in female rats treated with DMBA (7,12dimethyl benz (a) anthracene).27 This action is suggested to be mediated by virtue of mammotropic and/or lactogenic15 influence of A. racemosus on normal as well as estrogen- primed animals, which renders the mammary epithelium refractory to the carcinogen.27 Cardiovascular effects Alcoholic extract of the root of A. racemosus has been reported to produce positive ionotropic and chronotropic effect on frog's heart with lower doses and cardiac arrest with higher doses. The extract was found to produce hypotension in cats which was blocked by atropine, indicating cholinergic mechanism of action. The extract also produced congestion and complete stasis of blood flow in mesentric vessels of mice and rat. Slight increase in the bleeding time and no effect on clotting time was observed on I.V. administration of the extract in rabbits.28 Effect on respiratory system Higher doses of the alcoholic extract of root of A. racemosus are reported to cause dilatory effect on bronchial musculature of guinea pigs but failed to antagonise the histamine induced broncho-constriction. The extract has also been reported to produce depression of respiration in cat.28 Effect on CNS Neither stimulant nor depressant action of lactare on central nervous system has been reported in albino mice.18 Shatavari did not produce catalepsy in experimental rats even with massive oral doses suggesting that its action may be outside the blood-brain barrier, similar to that of metoclopromide.7 Miscellaneous effects Alcoholic extract of root of A. racemosus was found to have slight diuretic effect in rats and hypoglycemic effect in rabbits, but, no anticonvulsant and antifertility effect was observed in rats and rabbits respectively. However, it did show some anti-amoebic effect in rats.28 Toxic effects In Ayurveda, A. racemosus has been described as absolutely safe for long term use, even during pregnancy and lactation. Systemic administration of higher doses of all the extracts did not produce any abnormality in behaviour pattern of mice and rat.13 LD50 of the product lactare has not been assessed since it did not produce mortality even upto the oral dosages of 64 gm/kg.18 REFERENCES
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