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1 Asian Journal of Pharmaceutical and Biological Research Antistress effect of Mentha piperita in rats and the role of brain serotonin and dopamine Tahira Parveen*, Naila Amin, Darakhshan Saleem, Faiza Razi, Saida Haider, Darakhshan.Jabeen Haleem 1 Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Karachi-75270, Pakistan 2. Department of Biomedical Engineering, Sir Syed University. Karachi. Pakistan Abstract Objective: Stress is the emotional and tangible exertion caused by our response to pressure from the outside world. Common stress reactions include tension, irritability, inability to concentrate and a variety of physical symptoms that include headache and a fast heart beat. The present study investigates stress relieving effects of an herbal extract Mentha piperita in rats. Methods: Animals are divided into test and control group. Peppermint extract (0.1gm/kg) given to test animals. Control animals were received an equal volume of water. A group of test and control animals were restraint for 2 hours. 24 hours following the restraint stress different behaviors were monitored. After monitoring the behaviors rats were decapitated. Neurochemical estimation were performed by High Performance Liquid Chromatography using EC detector. Results: Exposure to 2h restraint stress increased circulating levels of plasma corticosterone. Brain Serotonin and Dopamine metabolism also increased. Prior administration of Mentha piperita leave extract for 5 week reversed the effect of stress on plasma corticosterone levels, brain Serotonin and Dopamine metabolism. Decrease in stress induced anxiety levels also observed in mint treated animals. Conclusion: The results are consistent with antistress effect of Mentha piperita and suggest a role of brain Serotonin and Dopamine in antistress effect. Key Words: Stress, Mentha piperita, Corticosterone, 5-HT. Original Article Received :11 Feb 2012 Accepted :28 Feb 2012 Published:10 Mar 2012 INTRODUCTION int leaves and peppermint is very Mcommon all over the world and it is not expensive and very easy to use. The scientific name of peppermint is Mentha piperita, also known as M. balsamea Willd. It is a hybrid mint, a cross between the watermint and spearmint.it is sometimes considered as [1] 'the world's oldest medicine. The leaves of peppermint have long been popular for not only their immense taste and soothing medicinal properties and use to treat [2] symptoms of the common cold. Peppermint aromatherapy in particular is often used for nausea, [3] alertness and energy as well as general stress relief. Peppermint tea may act as an agent used to neutralize or counteract the effects of a poison and also used in relieving aches and pains, stomach cramping, headaches, symptoms of colds and flu, stress and more. Peppermint tea is caffeine free and it will give an energy Address for correspondence* Tahira Parveen Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Karachi-75270, Pakistan. tahiraatiq@hotmail.com e ISSN: Asian J Pharm Biol Res [4] burst. Peppermint has topical use, it relieves tension [5] headaches and it is equivalent to acetaminophen. It has been reported that dopamine contribute in [6] ambulation promoted by menthone in mice. Since bupropion (BUP), a dopamine (DA) uptake inhibitor, promotes mouse ambulation, the effect of menthone (MTN) with the addition of BUP on ambulation was examined. The results showed that BUP with MTN induced a cumulative interaction on mouse ambulation. The effects of DA antagonists' chlorpromazine, fluphenazine, haloperidol, SCH12679 and spiperone on the ability of MTN to promote ambulation were then investigated. All of these antagonists reduce the effects of MTN. These results suggest that DA is involved in the [6] ability of MTN to promote ambulation in mice. 73 Stress is an important impetuous factor in [7] depression. It has been previously reported that behavioral changes occur after exposure to inevitable [8] stress. Episodes of 2h restraint stress produced great [9, 10] loss of appetite in rats. The finding suggests ability of considering many lives stresses that combine to effect [11] depression and anxiety. Depression results from a deficiency of serotonin or insufficient serotonin. This is

2 Asian J Pharm Biol Res Jan-Mar 2012 Vol-2 Issue-1 evident by the observation regarding the alterations in 5- hydroxy tryptamine (5-HT) and 5-hydroxy indol acetic [12] acid (5-HIAA) in patient during depressive episodes. In view of these findings present study is designed to investigate the effect of menthe piperita on stressed induced behavioral deficits and neurochemical changes. MATERIALS AND METHODS Animals Locally bred albino Wistar rats weighing g purchased from the HEJ research institute of chemistry, university of Karachi. Animals were housed individually in cages and randomly divided in two groups. Animals of test group were administered by peppermint extract and the animals of control group were administered by water. All experiments were performed according to a protocol approved by the local Animal Care Committee. Experimental dose Peppermint extract (0.1gm/Kg) given to six test animals in a dose of 150 ml twice a week. Experimental Protocol In the beginning of experiment 12 animals were divided equally into tape water and peppermint extract (0.1gm /kg). The animals were administered about 250 ml twice in a week till the end of the experiment. Food intake and body weight of all rats were measured once in a week. After 5 weeks administration light dark box activity was monitored for 10 min. than animals were further divided into unrestrained and restrained subgroups. Animals of restrained groups were restrained for 2 h. The animals assigned for unrestrained groups were left to their home cages. Next day post stress again light dark box activity was monitored and after that all the rats were decapitated. Brain and plasma samples were collected neurochemical analysis performed by High pressure liquid Chromatography using EC (HPLC-EC) detector. O and stored at -70 C which were used for Restraining the animals The animals were restrained on wire grids of 10?x9? fitted with a Perspex plate of 9?x6.5?. [9] Restraining procedure was same as described earlier. Immobilization was affected by pressing the fore legs of the rats through the gaps in the metal grids and taping them together with Zinc Oxide plaster tape. Hind limbs were also taped and the head of animal rested on the Perspex plate. After 2h of restraining period the animals were released and returned to their home cage. Light-dark activity test A test was conducted in a locally made twocompartment box. The compartment of equal size (26x26x26 cm), with an access (12x12 cm) between the compartments, differed in their sensory properties. Walls of one compartment were light (transparent) and other dark (black). A rat placed in this box is expected to pass [13] more time in the dark compartment. To determine the activity, a rat was placed in the light compartment of the box. Time spent in the light compartment was monitored for a cut off time of 5min. Neurochemical Analysis Concentration of brain 5-HIAA, 5-HT, DOPAC and DA were estimated by High Performance Liquid Chromatography using EC detector. Samples were [9, 14] extracted as described earlier. A 4um Novapak ODS, 4.6mm i.d. x 15cm separation column was used. The solvent system was methanol (14%), octyle sodium sulphate (0.023%) and EDTA (0.0035%) in 0.1 M phosphate buffer. Electrochemical detection was performed at an operating potential of 0.8V (glassy carbon electrode V/S Ag/AgCl reference electrode). Biochemical Estimations The plasma corticosterone levels were estimated [15] [16] by the method of Mettingly and LeBlanc as [17, 18] described by Haleem et al. in 1992and Statistical Analysis Behavioral and Neurochemical data were analyzed by two way ANOVA. Posthoc analysis was done by Newman-Keuls test: test and results are presented as means + S.D. p values >0.05 were considered non-significant. RESULTS Figure 1 shows the effect of 2hr restraint stress on anxiolytic activity in light dark box in water and mint treated rats. 2 way ANOVA (df =1, 20) showed significant effect of mint intake on no. of entries in light box (F=3.29, p<0.05), insignificant effect of stress (F=0.024, P>0.05) and insignificant interaction between the two factors (F=0.8, p>0.05). Two way ANOVA revealed significant effect of mint intake (F=1691, p<0.01), non significant effect of stress (F=0.72, p>0.05), and significant interaction between stress and mint intake on time spent in light box (F=64.33, p<0.01). Post-hoc analysis by Newman-keuls test showed that 2h restraint stress significantly decreased (p<0.01) time spent in light box in water and mint treated rats, these levels are significantly increased (p<0.01) in mint treated restraint rats compared to water treated restraint rats. Figure 2 shows the effect of 2hr restraint stress on 74

3 Asian J Pharm Biol Res Jan-Mar 2012 Vol-2 Issue-1 dopamine and DOPAC levels in whole brain of water and mint treated rats. 2 way ANOVA (df =1, 20) showed significant effect of mint intake on dopamine levels in whole brain (F=270.9, p<0.01), significant effect of stress (F=387.8, p<0.01) and significant interaction between two factors (F=189.1, p<0.01). Two way ANOVA revealed significant effect of mint intake on DOPAC levels (F=2541, p<0.01), significant effect of stress (F=111, p<0.01) and significant interaction between stress and mint intake on DOPAC levels in whole brain (F=1504, p<0.01). Post-hoc analysis by Newman-keuls test showed that 2h restraint stress significantly increased (p<0.01) Dopamine levels in water treated but not in mint treated rats. A significant decrease in dopamine levels was observed in mint treated restrained rats when compared with their respective water treated restrained rats. Posthoc analysis by Newman-keuls test showed that 2h restraint stress significantly increased (P<0.01) DOPAC levels in whole brain in water treated rats and mint Figure 1: The effect of 2 hr restraint stress on no. of entries and time spent in light dark box in water and mint treated rats. Values are means ± SD (n=6). Significant differences by 2 way ANOVA *p<0.01 Figure 2: The effect of 2 hr restraint stress on dopamine and DOPAC levels in whole brain of water and mint treated rats. Values are means ± SD (n=6). Significant differences by 2 way ANOVA *p<

4 Asian J Pharm Biol Res Jan-Mar 2012 Vol-2 Issue-1 treated rats, however the levels of DOPAC significantly (P<0.01) increased in mint treated unrestraint rats and decreased (p<0.01) in mint treated restrained rats compared to water treated restrained rats. Figure 3 shows the effect of 2hr restraint stress on 5-HT and 5HIAA levels in whole brain of water and mint treated rats. 2 way ANOVA (df =1, 20) showed significant effect of mint intake on 5-HT levels in whole brain (F=81.52, p<0.01). Significant effect of stress (F=15, p<0.01) and significant interaction between two factors (F=743.1, p<0.01). Two way ANOVA revealed significant effect of mint intake on 5HIAA levels (F=966.8, p<0.01), significant effect of stress (F=78.3, p<0.01) and significant interaction between stress and mint intake on 5HIAA levels in whole brain (F=135.2, p<0.01). Post-hoc analysis by Newman-keuls test showed that 2h restraint stress significantly increased (P<0.01) 5HT levels in water treated but not in mint treated rats. A significantly decreased in 5HT levels observed in mint treated rats when compares with their respective water treated rats. And Post-hoc analysis by Newman-keuls test showed that 2h restraint stress significantly increased (P<0.01) 5HIAA levels in whole brain in water treated rats and mint treated rats, however the levels of 5HIAA significantly (p<0.01) lower in mint treated restrained Figure 3: The effect of 2 hr restraint stress on 5-HT and 5HIAA levels in whole brain of water and mint treated rats. Values are means ± SD (n=6). Significant differences by 2 way ANOVA *p<0.01 Figure 4: The effect of 2 hr restraint stress on plasma corticosterone levels of water and mint treated rats. Values are means ± SD (n=6). Significant differences by 76 rats compared with their respective water treated control. Figure 4 shows the effect of 2hr restraint stress on plasma corticosterone levels of water and mint treated rats. 2 way ANOVA (df =1, 20) showed significant effect of mint intake (F=51.96, p<0.01), significant effect of stress (F=54.98, p<0.01) and significant interaction between stress and mint intake on corticosterone levels (F=93.84, p<0.01). Post-hoc analysis by Newman-keuls test showed that 2h restraint stress significantly increased (p<0.01) plasma corticosterone levels in water treated rats but not in mint treated rats. Levels of corticosterone significantly decreased (p<0.01) in mint treated restraint rats as compared to water treated restraint rats. DISCUSSION It has been reported in previous studies that 2hr [19] restraint stress produces behavioral deficits. Many studies which have been done on humans show that

5 aroma inhalation of peppermint reduced anxiety levels and stress scores indicating that peppermint can act as [20] anxiolytic and antistress compound. In present study it is observed that 5 week administration of peppermint extract produced anxiolytic effects in 2hr restraint stress rats. Dopamine has been also associated with anxiety [16] and depression. Stress has no significant effect on dopamine levels but increases DOPAC and HVA levels [21]. It is observed that an episode of 2hr restraint stress increases dopamine and DOPAC levels in whole brain. These stress induced increases in DA and DOPAC levels are not observed in mint treated rats. The role of serotonin in anxiety is supported by its modulatory effect in different brain reagions. Decreased serotonin activity is largely associated with depression and mostly antidepressants which are effective have been shown to [22] enhance the functioning of serotonin. The present study shows that peppermint attenuated the 5-HT metabolism in restrained rats as it is also reported previously.serotonin levels have been reported to increase in whole brain in following 1, 2, 4h [23] immobilization. The present study shows that stress response to serotonin and dopamine are reversed in mint treated animals. Stress activates the hypothalamic-pituitaryadrenal (HPA) axis and causes an increase in plasma [24] levels of corticosterone. Stress induced increases in plasma corticosterone levels also observed in present study but these increases are reversed in mint treated rats. CONCLUSION Reversal of stress induced increases brain 5-HT and 5-HIAA levels together with a decreased in plasma corticosterone levels following Mentha Piperita treatment observed in present study suggests that HPA axis play an important role in antistress effect of Mentha Piperita. REFERENCES 1. World Health Organization. "WHO monographs on s e l e c t e d m e d i c i n a l p l a n t s Vo l u m e 2 " [ pdf]. Retrieved 3 June Hills J: The mechanism of action of peppermint oil on gastrointestinal smooth muscle. Gastroenterol., 1991, 101: Anderson LA, Gross JB: Aromatherapy with peppermint, isopropyle alcohol, or placebo is equally effective in relieving postoperative nausea. J. Asian J Pharm Biol Res Jan-Mar 2012 Vol-2 Issue-1 Perianesth. Nurse., 2004, 19: Gobel H, Fresenius J, Heinze A: Effectiveness of Oleum menthae piperitae and paracetamol in therapy of headache of the tension type. Nervenarzt. 1996, 67: Gobel H, Schmidt G, Soyka D: Effect of peppermint a n d e u c a l y p t u s o i l p r e p a r a t i o n s o n neurophysiological and experimental algesimetric headache parameters. Cephalalgia., 1994, 14: Umezu T, Sakata A, Ito H: Ambulation-promoting effect of peppermint oil and identification of its active constituents. Pharmacol. Biochem. Behav., 2001, 69: Leonard BE: Stress nor-epinephrine and depression. J. Psychiat. Neuro. Sci., 2001, 26: Amat J, Sparks PD, Griggs P: The role of habhular complex in the elevation of dorsal raphe nucleus serotonin and the changes in the behavioral responses produced by uncontrollable stress. Brain Res., 2001, 917 (1): Haleem DJ, Parveen T: Brain regional serotonin synthesis following adaptation to repeated restraint. Neuro. Report., 1994, 5: Haleem DJ, Hajra N, Perveen T, Haider S, Ahmed SP, Nadia SK, Haleem MA: Serotonin and serotonin 1A receptors in the failure of ethanol treated rats to adapt to a repeated stress schedule. J. Stud. Alcohol., 2002., 163: Fisher L, Chesla CA, Mullan JT: Contributors of depression in Latino and Eurpeon-American patients with type-2 diabetes. Diab. Care., 2001, 24 (10): Brown G, Ebert M, Goyer P, Jimerson D, Klein W, Bunney W, Goodwin F: Aggression, suicide, and serotonin: relationships to CSF amine metabolites. Am. J. Psychiatry., 1982, 139: Samad N, Parveen T, Haider S, Haleem DJ: Attenuation of restraint-induced anorexia and anorexigenic behavior by serotonin-1a agonists in rats. J. Med. Sci., 2005, 5 (4): Haleem DJ, Haider S: Food restriction decreases serotonin and its synthesis rate in hypothalamus. Neuro. Report., 1996, 7: Mattingly D: A simple fluorimetric method for the estimation of free 11 hydroxysteroids in human plasma. J. Clin. Path., 1962, 15: LeBlanc J, Ducharme MB: Plasma dopamine and 77

6 noradrenaline variations in response to stress. Physio. & Behav., 2007, 91: Haleem DJ: Repeated coreticosterone treatment attenuates behavioral and neuroendocrine responses to 8-hydroxy-2(di-n-propylamino) tetraline in rats. Life. sci., 1992, 51: Haleem DJ: Function specific supersensitivity of m- chlorophenyl piperazine-induced serotonergic neurotransmission in female compared to male rats. Life. sci., 1993, 52: Kennette GA, Chauloff F, Marcou M, Curzon G: Female rats are more vulnerable than males in animal models of depression: the possible role of serotonin. Brain. Res., 1986, 382: Asian J Pharm Biol Res Jan-Mar 2012 Vol-2 Issue-1 20.Park M, Lee E: The effect of aroma inhalation method on stress responses of nursing students. Taehan. Kanho. Hakhoe. Chi., 2004, 34 (2): Allegra S, Imperato A, Angelucci L, Cabib S: Acute stress induces time-dependent responses in dopamine mesolimbic system. Brain Res., 1991, 554 (2): Ninan and Philip T: The functional anatomy, neurochemistry, and pharmacology of anxiety. J. Clin. Psychiat., 1999, 60 (22): Bhattacharya SK, Bhattacharya D: Effect of restraint stress on rat brain serotonin. J. Biosci., 1982, 4 (3): Chrousos GP, Gold PW: The concepts of stress and stress system disorders. Overview of physical and 78