Journal of Pharmacy And Bioallied Sciences

: 2015  |  Volume : 7  |  Issue : 1  |  Page : 26--31

Phytotherapy of experimental depression: Kalanchoe integra Var. Crenata (Andr.) Cuf Leaf Extract

Kennedy K E Kukuia1, Isaac J Asiedu-Gyekye2, Eric Woode3, Robert P Biney3, Emmanuel Addae3,  
1 Department of Pharmacology, University of Ghana Medical School, University of Ghana, Accra, Ghana
2 Department of Pharmacology and Toxicology, University of Ghana Medical School, University of Ghana, Accra, Ghana
3 Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana

Correspondence Address:
Kennedy K E Kukuia
Department of Pharmacology, University of Ghana Medical School, University of Ghana, Accra


Context: Kalanchoe sp. have been used since 1921 for central nervous system (CNS) disorders such as psychosis and depression. It is known to possess CNS depressant effects. Aims: To investigate the antidepressant properties of the aqueous leaf extract of Kalanchoe integra. Settings and Design: The study was carried out at the Kwame Nkrumah University of Science and Technology between 6 a.m. and 3 p.m. Materials and Methods: ICR mice were subjected to the forced swimming test (FST) and tail suspension test (TST) after they had received extract (30-300 mg/kg), fluoxetine (3-30 mg/kg), desipramine (3-30 mg/kg) orally, or water (as vehicle). In a separate experiment, mice were pre-treated with reserpine (1 mg/kg), α-methyl paratyrosine (AMPT; 400 mg/kg), both reserpine (1 mg/kg) and AMPT (200 mg/kg) concomitantly, or p-chlorophenylalanine (pCPA; 200 mg/kg) to ascertain the role of the noradrenergic and serotoninergic systems in the mode of action of the extract. Statistical analysis used: Means were analyzed by analysis of variance (ANOVA) followed by Newman-Keuls«SQ» post hoc test. P < 0.05 was considered significant. Results: In both FST and TST, the extract induced a decline in immobility, indicative of antidepressant-like effect. This diminution in immobility was reversed by pCPA, but not by reserpine and/or AMPT. The extract increased the swimming and climbing scores in the FST, suggestive of possible interaction with serotoninergic and noradrenergic systems. In the TST, the extract produced increases in both curling and swinging scores, suggestive of opioidergic monoaminergic activity, respectively. Conclusions: The present study has demonstrated the antidepressant potential of the aqueous leaf extract of K. integra is mediated possibly by a complex interplay between serotoninergic, opioidergic, and noradrenergic systems.

How to cite this article:
Kukuia KK, Asiedu-Gyekye IJ, Woode E, Biney RP, Addae E. Phytotherapy of experimental depression: Kalanchoe integra Var. Crenata (Andr.) Cuf Leaf Extract.J Pharm Bioall Sci 2015;7:26-31

How to cite this URL:
Kukuia KK, Asiedu-Gyekye IJ, Woode E, Biney RP, Addae E. Phytotherapy of experimental depression: Kalanchoe integra Var. Crenata (Andr.) Cuf Leaf Extract. J Pharm Bioall Sci [serial online] 2015 [cited 2022 Aug 9 ];7:26-31
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Full Text

Depression is a very common debilitating psychiatric disorder characterized by symptoms that hamper a person's ability to work, sleep, study, eat, and enjoy formerly pleasurable activities. [1],[2] It is estimated that more than 120 million people are affected worldwide. [3]

Notwithstanding the treatment advances, depression is still a major cause of morbidity and mortality. Current therapies are unable to offer full remission. Most patients (40%) are refractory to current depression pharmacotherapy and this serves as a testament to the limitations of the current medications. [4],[5] Furthermore, no antidepressant with rapid and sustained effect has been approved clinically, although there are reports of the availability of these agents. [6],[7] Considering that high suicidal rates among depressed patients are positively correlated with the delay in remission of symptoms, the unavailability of an approved drug with rapid onset, sustained effect, and less severe side effects that caters for the refractory conditions paints rather a gloomy picture. [6],[8] These reasons accentuate the need for more vigorous drug research that will lead to the discovery of the "wonder antidepressant."

The medicinal potential of plants and their usefulness in primary healthcare cannot be ignored. Medicinal plants are important repositories of bioactive agents that can be employed in the management of treatment-refractory conditions like depression. [9] Kalanchoe sp. has been used since 1921 in traditional medicine as an antipsychotic agent. [10] Previous studies have shown the antidepressant activity of Kalanchoe pinnata leaf extract, [11],[12] while Shashank demonstrated the antidepressant effect based on locomotor activity in mice using actophotometer. [13] The leaves of Kalanchoe integra have wide ethnomedical uses in Ghana and the plant has been found to possess central nervous system depressant effect.. [14] Though the plant has been reported as possessing central active properties, its possible effect in depression has not been investigated.

The study, therefore, investigated the effect of the aqueous leaf extract of K. integra in animal models of depression subjected to the forced swimming test (FST) and tail suspension test (TST).

 Materials and Methods


Fresh leaves of K. integra were collected from the botanical garden of the University of Ghana in October and sent to the Botany Department, University of Ghana for identification, authentication, and storage at the herbarium. A voucher specimen (IAGSP-001) was subsequently deposited in the herbarium at the Botany Department.

The fresh leaves (1 kg) were carefully washed under tap water and blended using Sanyo SM (G300) blender. The leaf extract was then strained using muslin cloth and freeze-dried to yield 150 g (15%) of the extract (also known as KIE). The powdered samples were stored at 4°C and used within 7 weeks after production.


Male ICR mice were obtained from Noguchi Memorial Institute for Medical Research, Accra, Ghana, and housed at the animal facility of the Department of Pharmacology, KNUST, Kumasi, Ghana. The animals were housed in groups of five in stainless steel cages (34 × 47 × 18 cm) with soft wood shavings as bedding, fed with normal commercial pellet diet (GAFCO, Tema, Ghana), given water ad libitum, and maintained under laboratory conditions. All animals used in these studies were treated in accordance with the Guide for the Care and Use of Laboratory Animals. [15]


Fluoxetine hydrochloride (Prozac; ) was from Eli Lilly and Co., Basingstoke, England. Desipramine hydrochloride, α-methyl paratyrosine (AMPT), reserpine, and p-chlorophenylalanine (pCPA) were purchased from Sigma-Aldrich Inc. (St. Louis, MO, USA).

Tail suspension test

The TST was carried out as described earlier, [16] with slight modifications given by Berocosso et al. [17] Mice were allowed to acclimatize to the room for 3.5-4 h before the test. Groups of 10 mice (n = 7) were treated with KIE (30, 100, or 300 mg/kg, p.o.), fluoxetine (FLX) (3, 10, or 30 mg/kg, p.o.), and desipramine (DSP) (3, 10, or 30 mg/kg, p.o.) or water (vehicle). One hour after oral administration of the test drugs, mice were individually suspended by the tail from a horizontal bar (distance from the floor = 30 cm) using an adhesive tape (distance from the tip of tail = 1 cm). Immobility (the absence of all movements except for those required for respiration), curling (active twisting movements), and swinging (vertical movement of the paws and/or side-to-side movement of body) behaviors were recorded for 5 min. The predominant behavior in each 5-s period of the 5 min was scored and the means computed. Mice that climbed up on their tails during the test session were gently pulled down and testing continued, but those that continued to climb up on their tails were excluded from the study.

Forced swimming test

The FST was based on that described by Porsolt et al. [18] Mice were randomly assigned to 10 groups of seven animals each. Water (vehicle), extract (30, 100, or 300 mg/kg, p.o.), or the standard reference drugs FLX (3, 10, or 30 mg/kg, p.o.) and DSP (3, 10, or 30 mg/kg, p.o.) were administered. One hour after oral administration of the test drugs, mice were gently placed individually in transparent cylindrical polyethylene tanks (25 cm high, 10 cm internal diameter) containing water (25-28°C) up to a level of 20 cm and left for 5 min. Each session was recorded by a video camera suspended approximately 100 cm above the cylinders. An observer scored the immobility (when mouse floated upright in the water and made only small movements to keep its head above water), swimming (active horizontal movements across water), and climbing (active vertical movement by the walls of the cylinder) behaviors during the 5 min test, from the videotapes with the aid of the public domain software JWatcher Version 1.0 (University of California, Los Angeles, USA and Macquarie University, Sydney, Australia; available at

Involvement of noradrenergic systems

Mice were pre-treated with reserpine and/or AMPT in order to investigate the possible role of noradrenergic system in the actions of KIE. [19] The doses of AMPT and reserpine were chosen on the basis of the work done by others. [19] To deplete newly synthesized pools of noradrenaline and serotonin, mice were treated with a single dose of AMPT (400 mg/kg, i.p.) 3.5 h before behavioral testing. To deplete the vesicular pools of noradrenaline and dopamine, mice were treated with a single dose of reserpine (1 mg/kg, s.c.) 24 h before behavioral testing. In an effort to deplete both the vesicular and cytoplasmic pools of noradrenaline and dopamine, mice were pre-treated with a combination of reserpine (1 mg/kg, s.c., 24 h before behavioral testing) and AMPT (200 mg/kg, i.p., 3.5 h before behavioral testing), respectively.

Involvement of serotoninergic systems

Mice were randomly assigned to 20 groups (n = 7). pCPA (200 mg/kg, i.p.) was administered once daily for three consecutive days to some of the animals. On the fourth day, group 1 received saline without pre-treatment; group 2 received pCPA after pre-treatment; groups 3-5 received KIE (30, 100, or 300 mg/kg) without pre-treatment; groups 6-8 received KIE (10, 30, and 100 mg/kg, p.o.) after pre-treatment; groups 9-11 received FLX (3, 10, and 30 mg/kg, p.o.) alone; groups 12-14 received FLX (3, 10, and 30 mg/kg, p.o.) after pre-treatment; groups 15-17 received DSP (3, 10, and 30 mg/kg, p.o.) alone; and finally groups 18-20 received DSP (3, 10, and 30 mg/kg, p.o.) after pre-treatment. After the tail suspension sessions, mice were taken through the FST.

Statistical analysis

GraphPad Prism for Windows version 5.03 (GraphPad Software, San Diego, CA, USA) was used for all data and statistical analyses. P < 0.05 was considered statistically significant. In all the tests, a sample size of 10 animals (n = 7) was used. Differences in means were analyzed by analysis of variance (ANOVA) followed by Newman-Keuls' post hoc test.


Effect of KIE on mean immobility, swimming, and climbing scores in the FST

Extract treatment significantly reduced the immobility score (34%; 100 mg/kg), increased the swimming score (28%; 100 mg/kg), and had a minimal effect on the climbing score. FLX, like the extract, decreased immobility and increased the swimming behavior, but had no effect on the climbing behavior. In contrast, DSP decreased immobility and swimming behavior, but increased the climbing behavior [Table 1].{Table 1}

Effect of KIE on mean immobility, swinging, and curling scores in the TST

In the TST, K. integra extract decreased the immobility score by 65% and increased both swinging score (by approximately 52%) and curling behavior (by 69%) (30 mg/kg). FLX also decreased immobility and increased swinging, but had no effect on curling behavior. DSP decreased immobility and increased the curling behavior, but had no effect on swinging [Table 2].{Table 2}

Involvement of the noradrenergic system

Depletion of monoamine stores with reserpine

Pre-treatment of mice with reserpine (1 mg/kg) failed to reverse the decline in immobility induced by extract treatment, but reversed this behavioral effect of FLX and DSP. Following reserpine treatment, however, the swimming score was decreased in extract-, FLX-, and DSP-treated mice. The climbing score was increased in extract-treated mice, but was decreased in DSP-treated mice compared to non-reserpine-treated mice. Climbing behavior was not affected by the administration of FLX [Table 3].{Table 3}

Inhibition of noradrenaline synthesis with AMPT

AMPT treatment failed to reverse the decline in immobility seen in extract-treated mice. It, however, potentiated the climbing behavior while reducing the swimming behavior induced by the KIE. The effect of FLX on the decline of immobility was not reversed compared to vehicle treatment, but that of DSP was totally reversed. Swimming score decreased in FLX-treated mice, but was still significantly higher when compared to vehicle treatment; climbing score was decreased. In contrast, the swimming score for DSP was increased by AMPT treatment, though this was not significant when compared to non-AMPT-treated groups; climbing scores were significantly reduced [Table 4].{Table 4}

Depletion of both newly synthesized noradrenaline and vesicular stores

Concomitant pre-treatment with reserpine and AMPT did not reverse the decline in immobility induced by the extract. The increase in swimming behavior induced by the extract was reversed, while the climbing behavior was potentiated by the administration of reserpine and AMPT. The pre-treatment reversed the declined in immobility induced by FLX and DSP. The increase in swimming score induced by FLX was reversed, while the decrease in swimming induced by DSP was not reversed. Moreover, the increase in climbing score caused by DSP and FLX was reversed by the pre-treatment [Table 5].{Table 5}

Effect of pCPA treatment on behavior in the TST

day pre-treatment with pCPA reversed the decline in immobility (partially) and the increase in curling and swinging behaviors caused by the extract. The pre-treatment reversed the behavioral effects of FLX by reversing the decline in immobility and increase in swinging (partial). pCPA treatment did not reverse the decline in immobility induced by DSP, but reduced the swinging and curling scores [Table 6].{Table 6}


The results from the present study indicate that K. integra has antidepressant-like effects in two widely used animal models for investigating the antidepressant effect of test compounds, the TST and FST. In both models, the extract caused a decline in immobility behavior while increasing various active behaviors like swimming, climbing, curling, and swinging.

Decline in immobility is used as the principal index for the antidepressant effect of test substances in these models. Indeed, virtually all antidepressants used medically induce a diminution in immobility in rodents, while other drugs fail to give the same response. [20],[21] KIE was able to cause a reduction in immobility behavior which is suggestive of an antidepressant-like effect.

In the FST, substances that increase the swimming score without altering the climbing behavior are purported to be acting via the serotoninergic pathway, while those that increase the climbing score without affecting swimming are sensitive to the noradrenergic pathway. [22],[23] Since the extract induced increases in both swimming and climbing scores, we hypothesized that it might be acting via both serotoninergic and noradrenergic pathways.

In the TST, the extract demonstrated its antidepressant effect by decreasing the immobility score and increasing both curling and swinging behaviors. Curling behavior is reported to be indicative of opioidergic activity. [17] The role of opioid as putative antidepressants is supported by the clinical effectiveness of μ-opioid receptor agonists such as tramadol, oxycodone, oxymorphone, etc., in the treatment of refractory depression. [24],[25],[26],[17] It is likely the antidepressant effect of the extract is partly dependent on its effect on opioidergic systems.

The impact of depletion of noradrenaline and serotonin on the behavioral effect of the extract was investigated. Pre-treatment of mice with reserpine potentiated the decline in immobility induced by the extract, reversed the increase in swimming, and further increased the climbing score. Reserpine is an irreversible inhibitor of the vesicular monoamine transporter 2 (VMAT-2) which is located chiefly within the CNS and is responsible for transferring monoamines from the cytoplasm into secretory vesicles. [27],[28] Treatment with reserpine, therefore, leads to depletion of vesicular monoamine stores-both serotonin and noradrenaline. [29] The failure to reverse the decline in immobility and increase in climbing score may suggest that depletion of vesicular stores of noradrenaline does not affect the action of the extract. It may also suggest that the extract acts directly on post-synaptic neurons, competitively inhibits the effect of reserpine, or the extract does not act on the noradrenergic pathways. That reserpine treatment reversed the swimming behavior while maintaining its decline in immobility may suggest that the antidepressant effect of the extract may be partially dependent on release of serotonin from the vesicles.

AMPT reduces synthesis of noradrenaline and dopamine by reversibly inhibiting the rate-limiting enzyme, tyrosine hydroxylase, thereby blocking the conversion of tyrosine to l-dopa. [30] Pre-treatment with AMPT did not reverse decline in immobility or increase in climbing for mice that received the extract. This further confirms that the antidepressant effect of the extract may not be dependent on noradrenergic pathways. Thus, the increase in climbing score when the extract was administered alone may not be as a result of direct action on noradrenergic pathways. The results were not different when mice were pre-treated with both AMPT and reserpine.

The possible contribution of serotonin or its pathway on the antidepressant effect of the extract was investigated in the TST by pre-treating mice with pCPA for 3 days. pCPA is a selective irreversible inhibitor of tryptophan hydroxylase, the enzyme responsible for serotonin (5-HT) synthesis. [31] The decline in immobility induced by the extract was partially reversed, suggesting that serotonin contributes to the antidepressant effect of the extract. In the absence of pCPA, the extract increased both curling and swinging behaviors. These behaviors were, however, reversed by pCPA pre-treatment. According to Berrocoso et al., swinging and curling behaviors are mediated by increase in monoaminergic and opioidergic neurotransmission, respectively. [17] The observed phenomenon suggests that the antidepressant effect of the extract involves a complex interplay between serotoninergic pathways and opioidergic neurotransmission. This is not surprising because the extract induced the Straub tail effect in mice (a rodent behavior sensitive to opioids) in a preliminary screening that was carried out (unpublished data).

Although this study was limited by our inability to look at other possible mechanisms by which the extract may act, e.g. glutamatergic neurotransmission, and also conduct in vitro studies to ascertain whether or not the extract acts specifically on receptors in the serotoninergic and opioidergic pathways, we can conclude that KIE has antidepressant-like potential.


The study has provided evidence that K. integra leaf extract has antidepressant effect which is mediated by a complex interplay of serotoninergic, opioidergic, and noradrenergic systems, when administered orally within the dose range.


1Holmes PV. Rodent models of depression: Reexamining validity without anthropomorphic inference. Crit Rev Neurobiol 2003;15:143-74.
2Gilmour H, Patten SB. Depression and work impairment. Health Rep 2007;18:9-22.
3Khawam EA, Laurencic G, Malone DA Jr. Side effects of antidepressants: An overview. Cleve Clin J Med 2006;73:351-53, 356-61.
4Belmaker RH, Agam G. Major depressive disorder. N Engl J Med 2008;358:55-68.
5Poleszak E, Wlaz P, Szewczyk B, Wlaz A, Kasperek R, Wrobel A, et al. A complex interaction between glycine/NMDA receptors and serotonergic/noradrenergic antidepressants in the forced swim test in mice. J Neural Transm 2011;118:1535-46.
6Gourion D. Antidepressants and their onset of action: A major clinical, methodological and pronostical issue. Encephale 2008;34:73-81.
7Machado-Vieira R, Salvadore G, Diazgranados N, Zarate CA Jr. Ketamine and the next generation of antidepressants with a rapid onset of action. Pharmacol Ther 2009;123:143-50.
8Ustun TB, Ayuso-Mateos JL, Chatterji S, Mathers C, Murray CJ. Global burden of depressive disorders in the year 2000. Br J Psychiatry 2004;184:386-92.
9Darwish RM, Aburjai T. A Effect of ethnomedicinal plants used in folklore medicine in Jordan as antibiotic resistant inhibitors on Escherichia coli. BMC Complement Altern Med 2010;10:9.
10Pattewar SV. Kalanchoe pinnata: Phytochemical and pharmacological profileInternational J Pharm Sci Res 2012;3:993-1000.
11Pal S, Sen T, Chaudhuri AKN. Neuropsycho-pharmacological profile of the methanolic fraction of Bryophyllum Pinnatum leaf extract. J Pharm Pharmacol 1995;51:313-8.
12Salahdeen HM, Yemitan OK. Neuropharmacological Effects of Aqueous Leaf Extract of Bryophyllum pinnatum in Mice. Afr J Biomed Res 2006;9:101-7.
13Shashank M, Ajay KJ, Cathrin M, Kumar M, Debjit B. Antidepressant activity of ethanolic extract of plant kalanchoe pinnata (Lam) Pers. In Mice. Ind J Res Pharm Biotech 2013;1:153-5.
14Varma RK, Ahmad A, Kharole MU, Garg BD. Toxicologic studies on Kalanchoe integra: An indigenous plant: Acute toxicity study. Indian J Pharmacol 1979;11:301-5.
15NRC. Guide for the Care and Use of Laboratory Animals. The National Academies Press; 1996.
16Steru L, Chermat R, Thierry B, Simon, P. The tail suspension test: A new method for screening antidepressants in mice. Psychopharmacology (Berl) 1985;85:367-70.
17Berrocoso E, Ikeda K, Sora I, Uhl GR, Sanchez-Blazquez P, Mico, JA. Active behaviours produced by antidepressants and opioids in the mouse tail suspension test. Int J Neuropsychopharmacol 2013;16:151-62.
18Porsolt RD, Le Pichon M, Jalfre M. Depression: A new animal model sensitive to antidepressant treatments. Nature 1977;266:730-2.
19O'Leary OF, Bechtholt AJ, Crowley JJ, Hill TE, Page ME, Lucki I. Depletion of serotonin and catecholamines block the acute behavioral response to different classes of antidepressant drugs in the mouse tail suspension test. Psychopharmacology (Berl) 2007;192:357-71.
20Cryan JF, Page ME, Lucki I. Differential behavioral effects of the antidepressants reboxetine, fluoxetine, and moclobemide in a modified forced swim test following chronic treatment. Psychopharmacology (Berl) 2005;182:335-44.
21Petit-Demouliere B, Chenu F, Bourin M. Forced swimming test in mice: A review of antidepressant activity. Psychopharmacology (Berl) 2005;177:245-55.
22Page ME, Detke, MJ, Dalvi A, Kirby LG, Lucki, I. Serotonergic mediation of the effects of fluoxetine, but not desipramine, in the rat forced swimming test. Psychopharmacol (Berl) 1999;147:162-7.
23Rénéric JP, Bouvard M, Stinus L. Idazoxan and 8-OH-DPAT modify the behavioral effects induced by either NA, or 5-HT, or dual NA/5-HT reuptake inhibition in the rat forced swimming test. Neuropsychopharmacol 2001;24:379-90.
24Spencer C. The efficacy of intramuscular tramadol as a rapid-onset antidepressant. Australian and New Zealand. J Psychiatry 2000;34:1032-3.
25Shapira NA, Verduin ML, DeGraw JD. Treatment of refractory major depression with tramadol monotherapy. J Clin Psychiatry 2001;62:205-6.
26Hegadoren KM, O'Donnell T, Lanius R, Coupland NJ, Lacaze-Masmonteil N. The role of beta-endorphin in the pathophysiology of major depression. Neuropeptides 2009;43:341-53.
27Metzger RR, Brown JM, Sandoval V, Rau KS, Elwan MA, Miller GW, et al. Inhibitory effect of reserpine on dopamine transporter function. Eur J Pharmacol 2002;456:39-43.
28Ji J, McDermott JL, Dluzen DE. Sex differences in K + -evoked striatal dopamine output from superfused striatal tissue fragments of reserpine-treated CD-1 mice. J Neuroendocrinol 2007;19:725-31.
29Fukui M, Rodriguiz RM, Zhou J, Jiang SX, Phillips LE, Caron MG, et al. VMAT2 heterozygous mutant mice display a depressive-like phenotype. J Neurosci 2007;27:10520-9.
30Ankenman R, Salvatore MF. Low Dose Alpha-Methyl-Para-Tyrosine (AMPT) in the Treatment of Dystonia and Dyskinesia. J Neuropsychiatry Clin Neurosci 2007;19:65-9.
31Marta K, Władysława AD. Cytochrome P450 is regulated by noradrenergic and serotonergic systems. Pharmacol Res 2011;64:371-80.