DINESH CHANDRA AND A.K. MANDAL

Indian Journal of Pharmacology 2000; 32: 369-371 SHORT COMMUNICATION

Correspondence: Dr. Dinesh Chandra

TOXICOLOGICAL AND PHARMACOLOGICAL STUDY OF NAVBAL RASAYAN - AMETAL BASED FORMULATION

DINESH CHANDRA, A.K. MANDAL*

Department of Pharmacology and Pathology*, Maulana Azad Medical College, New Delhi-110 002.

Manuscript Received: 28.7.99 Revised: 5.4.2000 Accepted: 24.4.2000

Objectives: Toxicological and pharmacological studies of “Navbal Rasayan” a metal based Ayurvedicformulation used for the treatment of multiple sclerosis, have been carried out.

Methods: Acute and chronic toxicities studies were conducted in rats with oral graded doses (0.37 to 3.0g/kg) of Navbal Rasayan (NR). In-vitro study was carried out on isolated guinea pig ileum obtained fromcontrol or animal pretreated with oral NR, 1.5 g/kg for 3 days. Dose responses with acetylcholine, histamineand 5-HT were obtained. The analgesic activity of oral NR 1.5 g/kg for 3 days was evaluated in albinomice against acetic acid induced writhings. The hypnotic activity was measured with pentobarbital afteroral pretreatment with 1.5 and 3.0 g/kg NR for 3 days. The anti-convulsant activity was observed in ratsagainst i.p. pentylenetetrazol induced seizures.

Results: Oral administration of graded doses of NR (upto 3.0 g/kg) did not produce any acute or chronictoxicities in rats. Oral pretreatment of guinea pigs with NR (1.5 g/kg for 3 days) increased 36.43 time thehistamine dose while the agonistic effect of acetylcholine and 5-hydroxytryptamine was completelyattenuated. Further, NR neither exhibited any analgesic, sedative effect or anticonvulsant effect in rodents.

Conclusion: Toxicological and pharmacological study with NR in animals does not show any toxic effect.However, decrease or attenuation of agonistic activities of histamine, acetylcholine and serotonin needsfurther exploration.

Multiple sclerosis navbal rasayan Ayurvedic formulation

SUMMARY

KEY WORDS

INTRODUCTION

Navbal Rasayan(NR) developed by Late VaidyaChandra Prakash had been used for relapsing ty-phoid, chronic osteomyelitis, otitis and viral diseaseslike measles, chicken pox etc. However, the drug didnot show any antimicrobial activity against S. faecalis,K. pneumoniae, E. coli, P. aeruginosa, S. aureus, C.albicans, Cryptococus neoformans, SporotrichumSohenchii, Trichophyton mentagrophytes and As-pergillus fumigatus1. Despite its ineffectivenessagainst above microorganisms, empirical use of NRin osteomyelitis has been claimed very effective (Per-sonal Communication from Sharma SM, B-27, P.L.Sharma Hospital, Meerut, 1989). Its use has beenextended further in multiple sclerosis (MS) by VaidyaBalendu Prakash in 1993. Mass spectrometric analy-

sis showed the presence of 10.1 mg iron, 0.4 mgarsenic, 0.01 mg lead, 66.8 mg mercury and 19.0mg gold per gm of NR compund2. However, the abovemetallic preparation made his treatment controver-sial between contradictory subjective quality of lifeevaluation reports by the patients and the warning ofmultiple sclerosis society of New South Wales for thedangerous blood levels of arsenic and mercury inpatients taking NR, without mentioning any obviousadverse or lethal effect of the drugs (personal com-munication from Garry Pearce, Multiple SclerosisSociety fo New Wales, July 10, 1995.)

Hence, in the present study the acute and chronictoxicological studies have been carried out with oralsuspension of NR in gum acacia, and the pharma-cological animal screening in-vitro as well as in-vivowith this compound, has been designed3.

TOXICOLOGICAL & PHARMACOLOGICAL STUDY OF NAVBAL RASAYAN

MATERIALS AND METHODS

Albino rats weighing between 120 to 150 g, mice 20to 30 g and guinea pigs 300 to 400 g of either sexwere used.

Acute toxicity study in rats: Randomized fivegroups each having 6 animals were taken. Group 1was kept as control and group 2, 3, 4 and 5 wereadministered orally NR suspension in the dose of0.37, 0.75, 1.5 or 3.0 g/kg body weight. Toxic mani-festations like abnormal motor activity, alteration inwater or food intake, respiration; straub reaction,sedation, hypnosis, lacrimation and diarrhoea wereobserved for 6 h and the mortality for 24 h.

Chronic Toxicity study in rats: Similar to acute tox-icity study, group 1 was kept as control and group 2and 3 were administered orally NR suspension inthe dose of 1.5 and 3.0 g/kg body weight respec-tively for 1 month. Animal mortality was recordedduring the treatment period. At the end, the animalswere sacrificed with ether anaesthesia. The heart,kidney, liver and spleen were dissected out and pre-served in formalin for histopathological study.

Study on guinea pig ileum: Guinea pigs werepretreated with oral NR 1.5 g/kg of body weight for 3days, while control group was fed with gum acaciaalone. After the last dose of the drug the animalswere fasted for 24 h and water was given ad-libitum.Guinea pig was killed by stunning. Ileum was identi-fied, dissected out and mounted. Dose responseswith graded doses of acetylcholine, histamine and5-hydroxytryptamine (5-HT) were obtained and ED

50

were calculated.

Analgesic activity in mice: Chemical writhings wereproduced by injecting 0.6% acetic acid (10.0 ml/kg,i.p.). After 10 days of exposure to writhings the ani-mals were divided into two groups. Group 1 was keptas control and group 2 was pre-treated with oral NR(1.5 g/kg) for 3 days. The last dose was adminis-tered 30 min before injecting the acetic acid to pro-duce writhings.

Hypnotic activity in rats: The hypnotic effect ofpentobarbitol sodium (40.0 mg/kg, i.p.) was evalu-ated by measuring the time taken for loss, durationand recovery of wrighting reflex in control and NR(1.5 and 3.0 g/kg, p.o.) pretreated rats.

Anti-convulsant activity in mice: Chemical con-vulsions were produced by injecting pentylenetetra-zol (40.0 mg/kg, i.p.) in control and NR pretreatedmice. The time (in min) for onset of convulsions, du-ration for jerking, tonic and clonic phase were re-corded.

RESULTS

During acute toxicities studies, NR (3.0 g/kg, p.o.)neither produced any abnormal effect i.e. abnormalmotor activity, sedation, hypnosis, change in respi-ration, food and water intake, straubs reaction anddiarrhoea for 6 h nor any mortality within 24 h. Moreo-ver, no death was observed for next 10 days amongthese animals. Further, oral administration of NR (1.5and 3.0 g/kg) for one month did not produce any le-thal effect during the treatment period. No histopatho-logical changes were observed in heart, kidney,spleen and liver obtained from these rats.

In-vitro study, acetylcholine and 5-hydroxytryptaminedid not elicit any effect on ileum obtained from guineapig pretreated with oral NR (1.5 g/kg). However, highdoses of histamine could elicit the effect on the il-eum obtained from NR pretreated animals. The ED

50

worked out to be 10.2 µµµµµg/ml as compared to ED50

0.28 µµµµµg/ml in normal guinea pig ileum.

Oral Navbal Rasayan (1.5 and 3.0 g/kg) for 3 daysneither altered the number of writhings in mice norpentobarbitone induced sleeping time or pentylene-tetrazol induced convulsions in rats.

DISCUSSION

Generally, all the heavy metals produce nephrotox-icity and blood disorders. However, in India Ayurvedicphysicians using these metals as Bhasma - a metalpreparation treated with Ayurvedic Medicines for vari-ous ailments claimed their preparation as nontoxic.Navbal Rasayan has been used in multiple sclerosis(MS) patients in India and Australia. This prepara-tion contains iron, arsenic, lead, mercury and gold indifferent quantity. These metals were detected in dan-gerous level in the blood of the patients taking oralNR for MS in Australian patients by multiple sclero-sis society, New Wales (personal communication fromGarry Pearce). However, the society did not reportany secondary morbidity or increased mortality rate

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DINESH CHANDRA AND A.K. MANDAL

mercury and gold in blood or tissue of the animal.Further, the chronic toxicity was done only in rats.

ACKNOWLEDGMENTS

The authors are grateful to M/S V.C.P.C.R.F.,Dehradoon for financial assistance and Mr PraveenTyagi, Department of Medical Education, MaulanaAzad Medical College, New Delhi for typing the manu-script.

REFERENCES

1. Sarin JPS. Antimicrobial screening repor t on NavbalRasayan. Test Report No. PHT/LD/89/R-20 from CentralDrug Research Institute, Lucknow, 1989.

2. Report by Trace and Toxic Element Unit, Clinical Bio-chem-istry, Royal Prince, Alfred Hospital, Missenden Road,Camperdown, 1994, 2050.

3. Ghosh MN. Fundamental of Experimental Pharmacology.2nd Ed, Scientific Book Agency, Calcutta, 1984.

in these MS patients. In the present animal studytoo, there was no evidence of toxicity in acute orchronic toxicity studies. There was no pathologicalevidence of toxicity in kidney, liver, heart or spleen ofthe rats, fed with NR for one month. Moreover, NRdid not exhibit any analgesic, antiepileptic or hypnoticactivity.

It was interesting to note that NR pretreatment com-pletely blocked the effect of acetylcholine and 5-HTon guinea pig ileum. It increased the ED

50 value of

histamine by 36 times. Thus indicating the drug de-creased the sensitivity of guinea pig ileum to spas-mogenic neurotransmitters i.e., acetylcholine, 5-HTand histamine and seems to be of non-specific innature.

To conclude, NR is not showing any apparentuntowand effect during acute and chronic toxicitystudies. But, it has a powerful non-specific inhibitoryeffect on guinea pig ileum. The limitation of the studyis that we did not measure the iron, arsenic, lead,

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