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PHELA is a herbal traditional medicine that is under development for use as an immune booster in immune compromised individuals. Therefore, the aim of this study was to determine PHELA’s mechanism of action by observing for changes in cytokine profiles. Four groups of Sprague Dawley rats (n = 8) were treated daily and separately with normal-saline, cyclosporine-A, PHELA-only and PHELA+ cyclosporine-A. Thereafter, 4 animals from each group were sacrificed after 7 and 14 days of treatment. Serum Th1 cytokines (IL-2, IFN-γ and TNF-ά) and Th2 cytokines (IL-4 and IL-10) were measured by ELISA. The concentrations of Th1 cytokines in the PHELA-only treated group were similar to the control group on days 7 and 14. However, the Th1 cytokines were higher in the PHELA+cyclosporine-A treated group compared to cyclosporine-A group, and cyclosporine-A concentrations were similar in both groups. These results show that PHELA did not stimulate Th1 cytokines of a normal immune system but stimulated them when the immune system was suppressed by cyclosporine-A. In conclusion, PHELA is an immune-stimulant to a compromised immune system.Key words: PHELA, traditional medicine, cyclosporine-A, cytokines, immune stimulant

MSc (Pharmacology), North-West University, Potchefstroom Campus Background: Methamphetamine (MA), globally known as “crystal meth”, is a highly addictive psychostimulant, which can be easily synthesized by using over the counter medicine and common household items. It induces intense euphoria, insomnia, anxiety, aggressive tendencies, hyperactivity and psychosis. Millions of people world-wide are addicted to this substance, in fact, after cannabis and opioids, MA is the third most abused illicit substance in the world. Despite this, there is currently no available treatment for MA addiction and abuse. MA elicits its effects by a variety of pathways, including the monoaminergic-, inflammatory and cyclic adenosine monophosphate (cAMP)-phosphodiesterase 4 (PDE4)-cAMP response element binding protein (CREB) pathways. In South Africa MA is locally known as “Tik”, and its usage amongst the youth, especially in the Western Cape has become a major cause of concern. These factors raise the need for a safe, cost-effective treatment for MA addiction. The majority of South Africans use herbal medicine to treat psychiatric diseases and recent clinical studies began to focus on the clinical utility of antioxidants of plant origin in treating these disorders. There is however a lack of pre-clinical evidence on the safety and efficacy of such plant extracts. Sceletium tortuosum (ST), is an indigenous plant, which gained attention for being a PDE4- and serotonin reuptake inhibitor, which helps to alleviate symptoms of psychiatric diseases such as anxiety and depression. Moreover, recent studies have shown that PDE4 inhibitors might have the potential to attenuate some of the effects caused by MA addiction. Given ST’s inherent pharmacological properties, this study set out to evaluate the effects of a standardized extract of ST (Zembrin®= Z®) and its potential in modifying the bio-behavioural changes induced by MA exposure, during the development of MA addiction in a rat model. Aims: The aims of the current study were to evaluate whether sub-acute MA exposure causes behavioural- (e.g., reward, psychosis and hyperactivity) and neurochemical (regional brain monoamine levels) alterations in Sprague dawley (SD) rats and whether concurrent administration of Z® could prevent these bio-behavioural changes. Further, this study also investigated the bio- behavioural effects of Z® alone in healthy SD rats. Methodology: Eighty-four healthy male SD rats were divided into 7 groups (n = 12/group). Exposure and treatment continued for 8 days. To confirm the MA-exposure regimen one group received saline exposure intraperitoneally and saline administration through oral gavage and a second group received MA and saline exposure (intraperitoneally) on every alternative day and received concurrent oral saline administration. Thereafter four groups received alternative day MA and saline exposure (intraperitoneally) and concurrent administration of different doses of Z® (5mg/kg, 10mg/kg, 25mg/kg and 50mg/kg) via oral gavage. The last group received intraperitoneal saline exposure and concurrent Z® 25mg/kg oral administration. All rats were subjected to the open field test (OFT), a pre-pulse inhibition (PPI) test and a conditioned place preference (CPP) test to determine locomotor, sensorimotor gating and addictive-like behaviours respectively, after which striatal and hippocampal brain tissue were harvested for dopamine (DA), serotonin (5-HT), noradrenaline (NA) and their respective metabolite analysis. Results: MA alone induced significant addictive- (increased time spend in drug-paired compartment in the CPP) and psychotic (decreased %PPI) -like behaviour, with no significant effect on locomotor activity (OFT). Apart from significantly increasing hippocampal DA levels, MA did not induce any changes in any other striatal or hippocampal monoamine levels. Different doses of Z® did not affect MA-induced PPI deficits, although MA plus Z® 25mg/kg significantly decreased locomotor activity in the OFT. Concurrent MA and Z® 50mg/kg administration tended to increase place preference for MA in the CPP test. Concurrent saline and Z® 25mg/kg administration significantly decreased the average %PPI. Neurochemically, concurrent MA and Z® 25mg/kg administration increased striatal 5-HT- and 3,4-Dihydroxyphenylacetic acid (DOPAC) levels as well as hippocampal 5-HT levels. MA together with Z® 50mg/kg caused a significant increase in striatal 5-HT- and DOPAC levels and tended to increase striatal DA levels. Concurrent MA and Z® 5mg/kg tended to increase striatal DA and to decrease hippocampal NA. Saline with concurrent Z® 25mg/kg administration caused a significantly decrease in hippocampal NA- and 5-hydroxyindoleacetic acid (5-HIAA) levels. Conclusions: Concurrent MA and Z® 25mg/kg decreased locomotor activity, while concurrent MA and Z® 25mg/kg, as well as MA and Z® 50mg/kg administration significantly increased striatal- and hippocampal monoamine levels, without affecting PPI. Administration of Z® 50mg/kg during MA exposure tended to increase CPP. Concurrent saline and Z® 25mg/kg administration however significantly induced PPI deficits and significantly decreased hippocampal monoamine levels. Tentatively, Z® acts as a stimulant during MA exposure, hinting at its potential to act as a substitute for MA by preventing MA associated withdrawal symptoms, while the abusers receive other therapeutical interventions. This is similar to bupropion which is also a non-addictive stimulant drug (which increases DA levels by binding to the dopamine transporter (DAT) and inhibiting DA reuptake), that is used to treat MA withdrawal symptoms. However, further studies investigating Z® post MA exposure (viz. during the withdrawal stage), as well as the mechanisms of action of Z® are encouraged. Masters

MSc (Pharmacology), North-West University, Potchefstroom Campus BACKGROUND: Millions of people worldwide suffer from major depressive disorder (MDD) which can cause physical and emotional suffering for patients and their loved-ones. Unfortunately current treatment fails in approximately a third of MDD patients. This may be attributed to numerous side effects, delayed onset of action, and ineffective targeting of the many different, interrelated biological systems. This includes structural and functional brain alterations driven especially by decreased brain-derived neurotrophic factor (BDNF), and neurotransmitter abnormalities such as reduced monoamines (serotonin (5-HT), dopamine (DA) and norepinephrine (NE)). Evidently, new and more effective treatments are urgently needed. Fortunately, complementary medicines like plants and herbs with antidepressant effects offer untapped potential. This study set out to evaluate the antidepressant potential of the South African plant, Sceletium tortuosum (L.) N.E.Br. (Zembrin®) (ST), which displays diverse pharmacological attributes that offer potential antidepressant activity, e.g. 5-HT transporter (SERT) inhibition, upregulation of vesicular monoamine transporter 2 (VMAT-2), mild MAO-A inhibition, and inhibition of phosphodiesterase 4 (PDE4). These mechanisms have almost all been studied in vitro, leaving an urgent need for in vivo studies. Furthermore, ST has not been tested in combination with known antidepressant compounds to evaluate its potential as a possible augmentative therapy for MDD. AIM: To use acute and sub-chronic treatment paradigms with biobehavioural parameters to evaluate the antidepressant-like properties of ST, alone and in combination with the selective 5-HT reuptake inhibitor (SSRI), escitalopram (ESC), in the FSL rat. METHODOLOGY: 1) A fingerprint analysis of the alkaloid profile of ST was done using an ultra-performance liquid chromatography - tandem mass spectrometer (UPLC-MS). 2) Behavioural confirmation of the FSL model of MDD. 12 saline-treated FSL and 6 Flinders Resistant Line (FRL) rats (reference control) were used to confirm the depressive phenotype of the FSL rat, using the open field test (OFT) and forced swim test (FST). 3) Acute dose response studies in FSLs, using a 3-tier dose response with escitalopram oxalate (ESC) (3 groups (n = 10); 5, 10 or 20 mg/kg), and a 5-tier dose response with ST (5 groups (n = 10); 5, 10, 25, 50 or 100 mg/kg). Treatment spanned over 24 hours, followed by the OFT and FST. The results were used to establish a low-dose of ESC, and a therapeutic dose of ST. 4) A sub-chronic treatment response study wherein four groups of FSL rats (n = 12) received a) saline, b) low dose of ESC, c) a therapeutic dose of ST or d) combination therapy of ESC + ST, over 15 days. After the OFT and FST on days 13 and 15, animals were decapitated, with hippocampus and frontal cortex samples harvested for analysis of monoamines and BDNF. RESULTS: Four main alkaloids were identified and quantified in an UPLSC-MS chromatogram. FSL rats presented with significantly decreased swimming and struggling, and increased immobility versus FRL controls, thus reaffirming its face validity as a rodent model of MDD. ST and ESC showed dose-dependent antidepressant responses following acute treatment. ESC 5 mg/kg (ESC 5) was chosen as a low dose of ESC and ST 50 mg/kg (ST 50) was selected as the therapeutic dose of ST. Sub-chronically, ESC 5 and ST 50 alone displayed similar neurochemical changes with no significant antidepressant-like effects. ESC+ST significantly increased hippocampal 5-HT and NE, and locomotor activity, which is normally deemed positive in MDD treatment. However, increased immobility and decreased struggling are indicative of depressogenic effects. Furthermore, hippocampal 5-HT was significantly increased, possibly due to synergistic serotonergic effects of ST 50 and ESC 5. A hypersensitive inhibitory 5-HT1A response, characteristic of FSL rats, could have prompted 5-HT1A receptor-mediated “5-HT behavioural syndrome” presenting as passive coping in the FST and increased locomotion in the OFT. The apparent lack of antidepressant effects in the alone treatment groups may be due to delayed response attributed to delayed desensitization of inhibitory 5-HT1A receptors, typical of SSRIs. ST 50 alone increased hippocampal BDNF indicating potential of ST in the treatment of impaired cognition, ESC + ST reduced frontal cortical BDNF levels. CONCLUSION: ST and ESC induced dose-dependent antidepressant-like effects after acute treatment, however not after sub-chronic treatment. Combined sub-chronic treatment with ESC + ST appears to be depressogenic, displaying significant serotonergic activity at behavioural and neurochemical levels. ST 50 increasing hippocampal BDNF levels suggests promise in the treatment of mood and cognitive disorders. Masters