Hepatoprotective and Antioxidant Potential of Extracts from Whole Plant of Solanum surattense Burm

 

Patil Suhas A.*, Joshi V.G., Sambrekar S.N. and Desai N. S.

Maratha Mandal’s College of Pharmacy, Belgaum, India.

ABSTRACT:

Objectives: Alcoholic and aqueous extracts of Solanum surattense Burm were investigated for their Hepatoprotective and Antioxidant potentials against Liver injury induced by CCl4 in rats.

Methods: The liver damage was induced in male albino rats (150-200g) by administering CCl4 (2ml/kg) for 7 days and extent of damage was studied by assessing biochemical and Antioxidant level in liver parameters such as aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), total bilirubin, lipid peroxidase (LPO) with a reduction of total protein, superoxide dismutase (SOD), catalase, and glutathione S-transferase (GST) in experimental animals. Histopathological changes of liver sample were compared with respective control.

Results: Treatment of rats with alcoholic and aqueous plant extract (200mg/kg) for 7 days resulted in significant (P<0.001) reduction in serum marker enzymes and antioxidant levels to near normal against CCl4-treated rats. The protection effect was found to be comparable with Liv52 treated group.

Conclusion: The alcoholic extracts of Solanum surattense Burm have protected liver from CCl4 damage. The probable mechanism may be due to Steroid and Tannins known for their Antioxidant activity may potentially confer protection against oxidative stress induced liver injury.

 

KEYWORDS: Hepatoprotective, Antioxidant, Solanum surattense Burm, Carbon tetrachloride, Biochemical parameters, Histopathology

 

 

INTRODUCTION:

Herbal medicines have recently attracted much attention as alternative medicines useful for treating or preventing life style related disorders and relatively very little knowledge is available about their mode of action. There has been growing interest in the analysis of plant products which has stimulated intense research on their potential health benefits. The liver, because of its strategic anatomical location, is targeted by many kinds of xenobiotics and therapeutic agents particularly when administered orally. Moreover, the rapidly increasing morbidity and mortality rates from liver diseases are largely attributable to the repeated chemical insult either due to drug use/abuse or from environmental pollution. Unfortunately so far, in the modern era of medicine there is no specific treatment to counter the life threatening impact of these dreaded conditions1. Several plants have been investigated and reported to possess antioxidant property and hepatoprotective activity eg. Baliospermum montanum2, Ocimum sanctum3, Tamarindus indica3 etc. Similarly traditionally Solanum surattense burm. family -Solanaceae4,5 is used as Antiasthamatic, aperients, alterative, astringent, digestive, diuretic, febrifuge and pungent. Used in bronchitis, cough, constipation and in dropsy6, 7,8,9,10..


It is also used as anthelmintic, appetizer, carminative, helmenthiasis, flatulence, colic, dyspepsia, anorexia, leprosy, skin disorders, rheumatoid arthritis, phryngitis, urolithiasis, amenorrhoea, lumbago, cardiac disorders7,8,10 stomachic, anti-inflammatory, rejuvenating, epilepsy,7,11 enlargement of liver and spleen.12 Though the feedback from the patients treated by traditional healers is quite encouraging, hepatoprotective activity of Solanum surattense Burm has not been scientifically investigated. Therefore, the present study was planned to investigate the effect of extracts of Solanum surattense Burm in CCl4 induced liver damage in Wistar rats.

 

MATERIALS AND METHODS:

Preparation of Solanum surattense burm Extract:

Whole plant of Solanum surattense burm was collected from open field around Belgaum city in the month of September were identified and authenticated by the taxonomist Dr. Harsha Hegde and the herbarium (voucher No. RMRC-481) has been preserved at Regional Medical Research Centre Belgaum, a unit of Indian council for medical research New Delhi. Dried plants were powdered to moderately coarse grade. Petroleum ether, chloroform, alcohol and aqueous extracts were obtained by using soxhlet extractor. The extraction was continued for 12 cycles or until the solvent in the thimble was clears. After evaporating the solvent, the dark brown semisolid extract was obtained .The phytochemical analysis was carried out and further extract was kept in an air tight container at 40c for future use. Suspensions of each extract were freshly prepared using 0.1% Tween 80, for experimental use.

 

Phytochemical screening:

A preliminary phytochemical screening of Solanum surattense burm was carried out. The phytochemical profile was performed as described by Wagner et al13. The presence of Glycosides, carbohydrates, fats and oils alkaloids, proteins steroids and tannins.

 

Animals:

Swiss albino mice (20–25 g) and male Wistar rats (150–200 g) were procured from Venkatershwara Enterprises, Bangalore, Karnataka, India, and used throughout the study. They were housed in microlon boxes in a controlled environment (temperature 25±2°C and 12 h dark/light cycle) with standard laboratory diet and water ad libitum. The study was conducted after obtaining Institutional Animal Ethical Committee clearance.

 

Acute toxicity studies:

Acute oral toxicity (AOT) of Solanum surattense was determined using Swiss albino mice. The animals were fasted for 12 h prior to the experiment and were administered with single dose of extracts dissolved in 5% gum acacia and observed for mortality up to 48 hour (short term toxicity). Based on the short-term toxicity, the dose of next animal was determined as per OECD guideline 420.

 

 

Hepatoprotective activity:

Rats were divided into five groups, each group consisting of six animals.

• Group I: Controls received the vehicle of normal saline (2 ml/kg, p.o.).

• Group II: Received CCl4 (2 ml/kg, s.c.) at every 72 h for 10 days14.

• Group III: Received Liv52 3ml/kg p.o. for 10 days and simultaneously administered CCl4 (2 ml/kg, s.c.) at every 72 h.

• Group IV: Received alcoholic extract of Solanum surattense 200 mg/kg p.o. for 10 days and simultaneously administered CCl4 (2 ml/kg, s.c.) at every 72 h.

• Group V: Received aqwueous extract of Solanum surattense 200 mg/kg p.o. for 10 days and simultaneously administered CCl4 (2 ml/kg, s.c.) at every 72 h.

At the end of experimental period, all the animals were sacrificed by cervical decapitation. Blood samples were collected, allowed to clot. Serum was separated by centrifuging at 2500 rpm for 15 min and analyzed for various biochemical parameters.

 

Assessment of liver function:

Biochemical parameters i.e., aspartate amino transferase (AST)15, alanine amino transferase (ALT)15 , alkaline phosphatase (ALP)16, total bilirubin17 and total protein18, were analyzed according to the reported methods. The liver was removed, morphological changes were observed. A 10% of liver homogenate was used for antioxidant studies such as lipid peroxidation (LPO)19, superoxide dismutase (SOD)20, Catalase21, and glutathione S-transferase (GST)22. A portion of liver was fixed in 10% formalin for histopathological studies.

 

Histopathological studies:

After draining the blood, liver samples were excised, washed with normal saline and processed separately for histopathological observation. Initially the materials were fixed in 10% buffered neutral formalin for 48 hour and then with bovine solution for 6 hour. Paraffin sections were taken at 5 mm thickness processed in alcohol-xylene series and was stained with alum hematoxylin and eosin. The sections were examined microscopically for histopathology changes.

 

Statistical analysis:

The values were expressed as mean ± SEM. Statistical analysis was performed by one way analysis of variance (ANOVA) followed by Tukey multiple comparison tests. P values < 0.05 were considered as significant.

 

RESULTS:

Preliminary phytochemical studies revealed the presence of Glycosides, carbohydrates, fats and oils alkaloids, proteins steroids and tannins compounds. For the acute oral toxicity studies, the extract treated animals were observed for mortality up to 48 h. Based on the results the extract did not produce any mortality up to 2000 mg/kg body weight.

 

 


Table 1. Effect of of Solanum surattense on biochemical parameters in CCl4-induced   hepatotoxicity   in rats

Treatment

Dose (mg/kg)

AST

U/L

ALT

U/L

ALP

U/L

Total Protein

mg%

Total bilirubin     mg%

Control

–

46.32 ± 0.418

92.12 ± 0.641

122.40 ± 0.812

9.17 ± 0.057

0.97 ± 0.009

CCl4

2 ml/kg

294.20 ± 0.616a

483.60 ± 0.441a

259.10 ± 1.241a

5.42 ± 0.155 a

5.617 ± 0.124 a

Liv52

3ml

85.08 ± 0.596a,d

128.20 ± 0.484a,d

136.0 ± 0.362a,d

8.22 ± 0.131 a,d

1.16 ± 0.162 a,d

Alcoholic extract

200

88.27 ± 0.432ad

156.6 ± 0.606a,d

141.7 ± 0.805a,d

8.1 ±  0.133 ad

1.2 ± 0.074a, d

Aqueous extract

200

114.3 ± 0.546a,d

218.5 ± 0.352a,d

164.20 ± 0.672a,d

7.30 ±  1.107 a,d

2.01± 0.085a,d

N = 6; Values are expressed as mean ± SEM; a P< 0.001; b P< 0.01; c P< 0.05 Vs Control; d P< 0.001; e P< 0.01; f P< 0.05  Vs CCl4

Data were analyzed by using one way ANOVA followed by Tukey multiple comparison test.

 

Table 2. Effect of Solanum surattense on Antioxidant level in CCl4-induced hepatotoxicity in rat

Treatment

Dose (mg/kg)

LPO

SOD

CAT

GST

Control

–

11.40 ± 0.161

33.67 ± 0.366

59.16 ± 0.223

0.44 ± 0.025

CCl4

2 ml/kg

24.22 ± 0.088a

18.76 ±  0.245a

37.39 ± 0.276a

0.10 ± 0.005 a

Liv52

3ml

10.0 ± 0.242a,d

28.36 ± 0.309a,d

48.64 ± 0.167a,d

0.31 ± 0.014 a,d

Aqueous extract

200

14.33 ± 0.226ad

25.56 ± 0.286a,d

44.18 ± 0.214a,d

0.18 ±  0.012 a,d

Alcoholic extract

200

11.48 ± 0.284a,d

21.76 ± 0.248a,d

40.30±188a,d

0.22 ± 0.015 ad

N = 6; Values are expressed as mean ± SEM; a P< 0.001; b P< 0.01; c P< 0.05 Vs Control; d P< 0.001; e P< 0.01; f P< 0.05 Vs CCl4

 

Data were analyzed by using one way ANOVA followed by Tukey multiple comparison test.

LPO = μ moles of MDA/ min/mg protein; SOD = Units/min/mg protein; CAT = μ mole of H2O2 consumed/ min/mg protein

GST = μ moles of CDNB conjugation formed/min /mg protein

 


The effect of Solanum surattense on serum marker enzymes is presented in Table 1. The levels of serum AST, ALT, ALP, total bilirubin, were markedly elevated and that of protein decreased in CCl4 treated animals, indicating liver damage. Administration of alcoholic and aqueous extract of Solanum surattense at the doses of 200 mg/kg remarkably prevented CCl4-induced hepatotoxicity in a dose dependent manner. Analysis of LPO levels by thiobarbituric acid reaction showed a significant (P<0.001) increase in the CCl4 treated rats. Treatment with alcoholic and aqueous extract of Solanum surattense (200 mg/kg) significantly (P<0.001) prevented the increase in LPO level which was brought to near normal. The effect of Solanum surattense was comparable with that of standard drug Liv52 (Table 2).

 

CCl4 treatment caused a significant (P<0.001) decrease in the level of SOD, Catalase and GST in liver tissue when compared with control group (Table 2). The treatment of alcoholic and aqueous extract of Solanum surattense at the dose of 200 mg/kg resulted in a significant increase of SOD, Catalase and GST when compared to CCl4 treated rats. The liver of Liv52 treated animals also showed a significant increase in antioxidant enzymes levels compared to CCl4 treated rats.

 

Morphological observations showed an increased size and enlargement of the liver in CCl4 treated groups. These changes were reversed by treatment with Liv52 and also extract of Solanum surattense at the doses tested.

Histopathological studies, showed CCl4 to produce extensive vascular degenerative changes and centrilobular necrosis in hepatocytes. Treatment with alcoholic and aqueous extract of Solanum surattense. produced mild degenerative changes and absence of centrilobular necrosis when compared with control. All these results indicate a hepatoprotective potential of the extract.

 

DISCUSSION:

Carbon tetrachloride is one of the most commonly used hepatotoxins in the experimental study of liver diseases. The hepatotoxic effects of CCl4 are largely due to its active metabolite, trichloromethyl radica23. These activated radicals bind covalently to the macromolecules and induce peroxidative degradation of membrane lipids of endoplasmic reticulum rich in polyunsaturated fatty acids. This leads to the formation of lipid peroxides. This lipid peroxidative degradation of biomembranes is one of the principle causes of hepatotoxicity of CCl424. This is evidenced by an elevation in the serum marker enzymes namely AST, ALT, ALP, total bilirubin and decrease in protein.

 

In the assessment of liver damage by CCl4 the determination of enzyme levels such as AST, ALT is largely used. Necrosis or membrane damage releases the enzyme into circulation and hence it can be measured in the serum. High levels of AST indicates liver damage, such as that caused by viral hepatitis as well as cardiac infarction and muscle injury, AST catalyses the conversion of alanine to pyruvate and glutamate and is released in a similar manner. Therefore ALT is more specific to the liver, and is thus a better parameter for detecting liver injury. Elevated levels of serum enzymes are indicative of cellular leakage and loss of functional integrity of cell membrane in liver25. Serum ALP, bilirubin and total protein levels on other hand are related to the function of hepatic cell. Increase in serum level of ALP is due to increased synthesis, in presence of increasing biliary pressure26. Administration of CCl4 caused a significant (P<0.001) elevation of enzyme levels such as AST, ALT, ALP, total Bilirubin and decrease in total protein when compared to control. There was a significant (P<0.001) restoration of these enzyme levels on administration of the leaf extract in a dose dependent manner and also by Liv52 at a dose of 3 ml/kg. The reversal of increased serum enzymes in CCl4-induced liver damage by the extract may be due to the prevention of the leakage of intracellular enzymes by its membrane stabilizing activity. This is in agreement with the commonly accepted view that serum levels of transaminases return to normal with the healing of hepatic parenchyma and the regeneration of hepatocytes27. Effective control of ALP, bilirubin and total protein levels points towards an early improvement in the secretary mechanism of the hepatic cells.

 

A) Hepatocytes of Control group showed Normal tubular architecture of liver

 

B) Hepatocytes of CCl4 treated group showed liver cell necrosis

 

C) Hepatocytes of Liv52 pretreated group showed normal tubular architecture

 

D) Hepatocytes of Alcoholic extract pretreated Group showed minimal inflammation with moderate portal triadities and normal tubular architecture

 

E) Hepatocytes of Aqueous extract pretreated Group showed minimal inflammation with moderate portal triadities and normal tubular architecture

 

The efficacy of any hepatoprotective drug is dependent on its capacity of either reducing the harmful effect or restoring the normal hepatic physiology that has been distributed by a hepatotoxin. Both Liv52 and the plant extract decreased CCl4 induced elevated enzyme levels in tested groups, indicating the protection of structural integrity of hepatocytic cell membrane or regeneration of damaged liver cells.

 

The increase in LPO level in liver induced by CCl4 suggests enhanced lipid peroxidation leading to tissue damage and failure of antioxidant defense mechanism to prevent formation of excessive free radicals. Treatment with Solanum surattense significantly reverses these changes. Hence it is likely that the mechanism of hepatoprotection of Solanum surattense is due to its antioxidant effect.

 

Decrease in enzyme activity of superoxide dismutase (SOD) is a sensitive index in hepatocellular damage and is the most sensitive enzymatic index in live injury. Curtis and Mortiz28, SOD has been reported as one of the most important enzymes in the enzymatic antioxidant defense system. It scavenges the superoxide anion to form hydrogen peroxide and thus diminishing the toxic effect caused by this radical. In Solanum surattense causes a significant increase in hepatic SOD activity and thus reduces reactive free radical induced oxidative damage to liver.

Catalase (CAT) is an enzymatic antioxidant widely distributed in all animal tissues, and the highest activity is found in the red cells and liver. CAT decomposes hydrogen peroxide and protects the tissues from highly reactive hydroxyl radicals29. Therefore reduction in the activity of CAT may result in a number of deleterious effects due to the assimilation of superoxide radical and hydrogen peroxide. A higher dose (500 mg/kg) increases the level of CAT as produced by Liv 52, the standard hepatoprotective drug.

 

Glutathione is one of the most abundant tripeptide, non-enzymatic biological antioxidant present in the liver. It removes free radical species such as hydrogen peroxide, superoxide radicals and maintains membrane protein thiols. Decreased level of GSH is associated with an enhanced lipid peroxidation in CCl4 treated rats. Administration of Solanum surattense significantly (P<0.001) increased the level of GST in a dose dependent manner.

 

Extensive vascular degenerative changes and centrilobular necrosis in hepatocytes was produced by CCl4. Treatment with alcoholic and aqueous extract of whole plant of Solanum surattense produced only mild degenerative changes and absence of centrilobular necrosis, indicating its hepatoprotective efficiency.

 

Free radical mediated process has been implicated in pathogenesis of most of the diseases. The protective effect of Solanum surattense on CCl4 induced hepatotoxicity in rats appears to be related to inhibition of lipid peroxidation and enhancement of antioxidant enzyme levels in addition to free radicals scavenging action. Preliminary phytochemical studies reveal the presence of steroids and tannins in the extracts of Solanum surattense. steroids and tannins are hepatoprotectives30,31. The observed antioxidant and hepatoprotective activity of Solanum surattense may be due to the presence of steroids and tannins. Further studies to characterize the active principles and to elucidate the mechanism are in progress.

 

REFERENCES:

1.       Chatterjee TK. Herbal Options. Calcutta: Books and Allied (P) Ltd; 2000:155.

2.       Wadekar Raju Ratan, Supale Radhika Sachin, Tewari Kunal Mahesh, et al. Screening of roots of Baliospermum montanum for Hepatoprotective activity against paracetamol induced liver damage in albino rats. Int J Greenpharmacy 2008:220-223

3.       Chattopadhay R.R.Sarkar S.K, Ganguly S.,et al. Hepatoprotective activity of Ocimum sanctum leaf extract against paracetamol induced hepatic damage in rats. Indian J Pharmacol 1992; 24: 163-165.

4.       Kapoor LD. Handbook of Ayurvedic Medicinal Plants. 1990; 307.

5.       Indian Medicinal Plants. Vol.5 1996, RP 1997; 164-9.

6.       Dr. Gyanendra Pandey, Drvyaguna Vijanana (Materia medica of vegetable Drugs) part-11, 2001; 83-96.

7.       Ashma Chatarji, Satyesh Chandra Prakash. The treatise of Indian Medicinal Plants. Vol. 4, CSIR; 202-3.

8.       Nair CKN, N Mohanan Medicinal Plants of India. NAG Publishers Delhi: 399.

9.       Sharma Ravindra Plants of India an Encyclopedia Daya Pub. HouseDelhi].2003; 232-3.

10.     Saviol Y.K. Illustrated Manual of Herbal Drugs used in Ayurveda. Ind. Council Medical Research1996; 310

11.     Sharma PV Dravyaguna Vijnana. Bharati Academy pub. Vol. 2; 2005; 281-2.

12.     Nair CKN and Mohanan N.Medicinal plants of India,Nag publication, Delhi; 399

13.     Wagner H, Bladt S, Zgainski EM. Plant Drug Analysis. Springer – Verlag, Berlin: 1984, 298–334.

14.     Suja SR, Latha PG, Pushpangadan P, Rajasekharan S. Evaluation of hepatoprotective effect of Helminthostachys zeylanica (L) Hook against carbon tetrachloride induced liver damage in Wistar rats. J Ethnopharmacol. 2004; 92: 61. [doi:10.1016/j.jep.2004.01.019]

15.     Kind PR and King EJ. Estimation of plasma phosphates by determination of hydrolyzed phenol with antipyrin. J Clin Pathol. 1954; 7: 322–326. [doi:10.1136/jcp.7.4.322]

16.     Mallay HT and Evelyn KA. Estimation of serum bilirubin level with the photoelectric colorimeter. J Biol Chem. 1937; 119: 481–484.

17.     Lowry OH, Rosenbrough NJ, Farr AL and Randall, RJ. Protein measurement with Folin– Phenol reagent. J Biol Chem. 1951; 193: 265–275.

18.     Devasagayam TPA and Tarachand U. Decreased lipid peroxidation in the rat kidney during. Biochem Biophys Res Commun. 1987; 145: 134–138. [doi:10.1016/0006- 291X(87)91297-6]

19.     Marklund S and Marklund G. Involvement of superoxide anion radical in the autooxidationof pyrogallol and a convenient assay for superoxide dismutase. Eur J Biochem. 1974; 47: 469–474. [doi:10.1111/j.1432-1033.1974.tb03714.x]

20.     Sinha AK. Colorimetric assay of catalase. Anal Biochem.1972; 47: 389–394. [doi:10.1016/0003-2697(72)90132-7]

21.     Habig WH, Pabst MJ and Jakoby WB. Glutathione S-transferase, the first enzymatic step in mercapturic acid formation. J Biol Chem. 1974; 249: 7130–7139.

22.     Johnson DE, Kroening C. Mechanism of early carbon tetra chloride toxicity in cultured rat hepatocytes. Pharmacol Toxicol. 1998; 83: 231–239.

23.     Kaplowitz N, Aw TY, Simon FR, Stolz A. Drug induced hepatotoxicity. Ann Intern Med. 1986; 104: 826–839.

24.     Drotman R. and G. Lawhan. Serum enzymes are indications of chemical induced liver damage. Drug Chem Toxicol. 1978; 1: 163–171. [doi:10.3109/01480547809034433]

25.     Thabrew M and Joice P. A comparative study of the efficacy of Pavetta indica and Osbeckia octanda in the treatment of liver dysfunction. Planta Med. 1987; 53: 239–241[doi:10.1055/s-2006-962691]

26.     Curtis JJ and Mortiz M. Serum enzymes derived from liver cell fraction and response to carbon tetrachloride intoxication in rats. Gastroenterol 1972; 62: 84–92.

27.     Chance B and Greenstein DS. The mechanism of catalase actions-steady state analysis. Arch Biochem Biophys. 1992; 37: 301–339. [doi:10.1016/0003-9861(52)90194X]

28.     Prakash J, Gupta SK and Singh N. Chemo preventive activity of Withania somnifera in experimentally induced fibro sarcoma tumors in Swiss albino rats. Phytother Res. 2001; 15: 200–204. [doi:10.1002/ptr.779]

29.     Amrit Pal Singh and A.S.Sandhu Distribution of Steroid like Compounds in Plant Flora 2006 Published in: Pharmacognosy Magazine 2, 6, 87--89

30.     Cheeke PR.Piacente S and Oleszek W. Anti-inflammatory and anti-arthritic effects of yuccaschidigera: A review Journal of Inflammation 2006, 3:6doi:10.1186/1476-9255-3-6

31.     Nithiankool and Pithayankul Bavovada Hepatopotentials of extracts from seeds of Arecacatechu and NUtgulls of Quercus infectoria Molecules 2009, 14 ; 4987-5000 doi:10.3390/molecules 1412498.

 

 

Received on 06.12.2010

Accepted on 11.01.2010     

© AandV Publication all right reserved

Research Journal of Pharmacognosy  and Phytochemistry. 3(1): Jan. - Feb. 2011, 17-21