Harmaline induces apoptosis and inhibits migration in A2780 ovarian cancer cells in vitro.

Ovarian cancer is one of the most prevalent malignancies in women. Harmaline is reported to have powerful anticancer properties. We aimed to investigate the apoptotic and antimetastatic properties of harmaline in A2780 ovarian cancer cells. Cell viability, apoptosis, migration, and invasion were investigated in cells treated with harmaline. Reactive oxygen species (ROS) production, mRNA expression of apoptosis-associated genes, MMP-2, and MMP-9 were measured. Harmaline attenuated the viability of A2780 ovarian cancer cells in a dose- and time-dependent way. Furthermore, compared to NIH/3T3 mouse normal cell line (IC50 = 417 µM), the malignant A2080 cells were more sensitive to harmaline (IC50 = 300 µM after 24 h). Harmaline increased the production of ROS, raised the mRNA expression of p53 and the Bax/Bcl2 ratio. Harmaline also increased the proportion of cells in the late apoptotic and necrotic phases. MMP-2 and MMP-9's mRNA expression, gelatinase activity, and migration of A2780 cells also decreased by harmaline. These findings suggest that harmaline may have the potential to be a therapeutic drug for ovarian cancer by triggering apoptosis and suppressing invasion and migration.

Search for Novel Therapies for Essential Tremor Based on Positive Modulation of α6-Containing GABAA Receptors.

Background: Prior work using GABAA receptor subunit knockouts and the harmaline model has indicated that low-dose alcohol, gaboxadol, and ganaxolone suppress tremor via α6ßδ GABAA receptors. This suggests that drugs specifically enhancing the action of α6ßδ or α6ßγ2 GABAA receptors, both predominantly expressed on cerebellar granule cells, would be effective against tremor. We thus examined three drugs described by in vitro studies as selective α6ßδ (ketamine) or α6ßγ2 (Compound 6, flumazenil) receptor modulators. Methods: In the first step of evaluation, the maximal dose was sought at which 6/6 mice pass straight wire testing, a sensitive test for psychomotor impairment. Only non-impairing doses were used to evaluate for anti-tremor efficacy in the harmaline model, which was assessed in wildtype and α6 subunit knockout littermates. Results: Ketamine, in maximally tolerated doses of 2.0 and 3.5 mg/kg had minimal effect on harmaline tremor in both genotypes. Compound 6, at well-tolerated doses of 1-10 mg/kg, effectively suppressed tremor in both genotypes. Flumazenil suppressed tremor in wildtype mice at doses (0.015-0.05 mg/kg) far lower than those causing straight wire impairment, and did not suppress tremor in α6 knockout mice. Discussion: Modulators of α6ßδ and α6ßγ2 GABAA receptors warrant attention for novel therapies as they are anticipated to be effective and well-tolerated. Ketamine likely failed to attain α6ßδ-active levels. Compound 6 is an attractive candidate, but further study is needed to clarify its mechanism of action. The flumazenil results provide proof of principle that targeting α6ßγ2 receptors represents a worthy strategy for developing essential tremor therapies. Highlights: We tested for harmaline tremor suppression drugs previously described as in vitro α6ßδ or α6ßγ2 GABAA receptor-selective modulators. Well-tolerated flumazenil doses suppressed tremor in α6-wildtype but not α6-knockout mice. Compound 6 and ketamine failed to display this profile, likely from off-target effects. Selective α6 modulators hold promise as tremor therapy.

Epicranial Direct Current Stimulation Suppresses Harmaline Tremor in Rats.

INTRODUCTION: Essential tremor (ET) is the most common neurologic movement disorder worldwide. It is characterized by a postural tremor, mostly in the upper extremities, causing difficulties in daily activities that may lead to social exclusion. Some patients with ET do not respond well to or do not tolerate medication. Thus, deep brain stimulation can be offered. In a recent study, we proposed a novel neuromodulation technique called epicranial current stimulation (ECS) that works in a minimally invasive way by placing the electrodes subcutaneously under the skin and directly over the skull. In this study, we investigated the feasibility of using epicranial direct current stimulation (EDCS) to suppress tremor in a rat harmaline ET model. MATERIALS AND METHODS: In experiment 1, seven Sprague Dawley rats were implanted with ECS electrodes placed over the motor cortex (MC) and the cerebellum to investigate whether stimulating between them could suppress tremor. In experiments 2 and 3, eight rats were implanted with ECS electrodes placed over the MC, cerebellum, and the rostral skull to separate the effects on tremor caused by stimulating each target. During each experiment, the rats were injected with harmaline, which induced tremor that was quantified using an accelerometer. EDCS was then applied through the different electrode configurations to evaluate their tremor suppression effectiveness. RESULTS: Results from experiment 1 showed that MCcathode-Cerebellaranode suppressed tremor compared with stimulation-OFF but MCanode-Cerebellarcathode did not. Furthermore, experiments 2 and 3 showed that it was the cerebellar anodal electrode that was driving tremor suppression. CONCLUSION: Cerebellar EDCS suppressed harmaline tremor in rats in a polarity-dependent manner. EDCS could be a promising neuromodulation method for patients with ET.

Basolateral amygdala cannabinoid CB1 receptors mediate the antinociceptive activity of harmaline in adolescent male mice.

Evidence suggests a clear role for the amygdala endocannabinoid system in pain processing. Harmaline has been also known as the main nociceptive agent extracted from the Peganum harmala plant. In this study, the role of basolateral amygdala (BLA) cannabinoid CB1 receptors in pain sensitivity of harmaline-treated mice were assessed using tail-flick and hot plate methods in adolescent male NMRI mice. Intraperitoneal administration of two higher doses of harmaline (6 and 8 mg/kg) increased tail-flick latency, suggesting an antinociceptive activity. The same result was observed for the higher dose of harmaline in the hot plate test. Intra-BLA microinjection of CB1 receptor agonist ACPA (1 and 1.5 ng/mouse) or (1.5 ng/mouse) enhanced the ineffective dose-response of harmaline on pain threshold in the tail-flick or hot plate tests, respectively. Microinjection of two higher doses of CB1 receptor antagonist AM251 (0.5 and 1 ng/mouse) attenuated the antinociceptive activity of harmaline (8 ng/mouse) in both tail-flick and hot plate tests. Meanwhile, ACPA and AM251 did not alter latency to withdraw from the noxious stimulus in both tests, by themselves. It should be noted that the analgesic dose of the drugs alone or in combination did not affect locomotor activity. The obtained results highlight that BLA CB1 receptors mediate the antinociceptive activity of harmaline.

Peganum harmala enhanced GLP-1 and restored insulin signaling to alleviate AlCl3-induced Alzheimer-like pathology model.

Peganum harmala (P. harmala) is a folk medicinal herb used in the Sinai Peninsula (Egypt) as a remedy for central disorders. The main constituents, harmine and harmaline, have displayed therapeutic efficacy against Alzheimer's disease (AD); however, the P. harmala potential on sensitizing central insulin to combat AD remains to be clarified. An AD-like rat model was induced by aluminum chloride (AlCl3; 50 mg/kg/day for six consecutive weeks; i.p), whereas a methanolic standardized P. harmala seed extract (187.5 mg/kg; p.o) was given to AD rats starting 2 weeks post AlCl3 exposure. Two additional groups of rats were administered either the vehicle to serve as the normal control or the vehicle + P. harmala seed extract to serve as the P. harmala control group. P. harmala enhanced cognition appraised by Y-maze and Morris water maze tests and improved histopathological structures altered by AlCl3. Additionally, it heightened the hippocampal contents of glucagon-like peptide (GLP)-1 and insulin, but abated insulin receptor substrate-1 phosphorylation at serine 307 (pS307-IRS-1). Besides, P. harmala increased phosphorylated Akt at serine 473 (pS473-Akt) and glucose transporter type (GLUT)4. The extract also curtailed the hippocampal content of beta amyloid (Aß)42, glycogen synthase (GSK)-3ß and phosphorylated tau. It also enhanced Nrf2, while reduced lipid peroxides and replenished glutathione. In conclusion, combating insulin resistance by P. harmala is a novel machinery in attenuating the insidious progression of AD by enhancing both insulin and GLP-1 trajectories in the hippocampus favoring GLUT4 production.

Novel mechanism of harmaline on inducing G2/M cell cycle arrest and apoptosis by up-regulating Fas/FasL in SGC-7901 cells.

Harmaline (HAR), a natural occurrence ß-carboline alkaloid, was isolated from the seeds of Peganum harmala and exhibited potent antitumor effect. In this study, the anti-gastric tumor effects of HAR were firstly investigated in vitro and in vivo. The results strongly showed that HAR could inhibit tumor cell proliferation and induce G2/M cell cycle arrest accompanied by an increase in apoptotic cell death in SGC-7901 cancer cells. HAR could up-regulate the expressions of cell cycle-related proteins of p-Cdc2, p21, p-p53, Cyclin B and down-regulate the expression of p-Cdc25C. In addition, HAR could up-regulate the expressions of Fas/FasL, activated Caspase-8 and Caspase-3. Moreover, blocking Fas/FasL signaling could markedly inhibit the apoptosis caused by HAR, suggesting that Fas/FasL mediated pathways were involved in HAR-induced apoptosis. Interestingly, HAR could also exert on antitumor activity with a dose of 15 mg/kg/day in vivo, which was also related with cell cycle arrest. These new findings provided a framework for further exploration of HAR which possess the potential antitumor activity by inducing cell cycle arrest and apoptosis.

A dihydro-pyrido-indole potently inhibits HSV-1 infection by interfering the viral immediate early transcriptional events.

In our continued quest for identifying novel molecules from ethnomedicinal source we have isolated an alkaloid 7-methoxy-1-methyl-4,9-dihydro-3H-pyrido[3,4-b]indole, also known as Harmaline (HM), from an ethnomedicinal herb Ophiorrhiza nicobarica. The compound exhibited a potent anti-HSV-1 activity against both wild type and clinical isolates of HSV-1. Further we demonstrated that HM did not interfere in viral entry but the recruitment of lysine-specific demethylase-1 (LSD1) and the binding of immediate-early (IE) complex on ICP0 promoter. This leads to the suppression of viral IE gene synthesis and thereby the reduced expression of ICP4 and ICP27. Moreover, HM at its virucidal concentration is nontoxic and reduced virus yields in cutaneously infected Balb/C mice. Thus, the interference in the binding of IE complex, a decisive factor for HSV lytic cycle or latency by HM reveals an interesting target for developing non-nucleotide antiherpetic agent with different mode of action than Acyclovir.

Re-thinking the biology of essential tremor: from models to morphology.

Remarkably little has been written on the biology of essential tremor (ET), despite its high prevalence. The traditional pathophysiological model for ET, the olivary model, states that ET is a primary electrical//electrophysiological entity, the result of pacemaking neurons in the inferior olivary nucleus that begin firing in a coupled and rhythmic manner, and thus, through an abnormal olivo-cerebellar output, produce tremor. Though this model is based on several sound neurophysiological observations, there are major problems as well. Despite its shortcomings, however, the model persists. With the traditional focus in ET on clinical neurophysiology, there has been little research on pathological anatomy, cell biology, and molecular mechanisms, and over the years, there have been few alternatives to the olivary model. However, rigorous tissue-based studies have recently identified a series of structural changes in the ET brain, most of which are centered on the Purkinje cell and connected neuronal populations, and which may involve a partial loss of Purkinje cells. An implication of these newer studies is that ET could be degenerative. This shift in paradigm opens the door for research that aims to identify the primary set of molecular triggers and the cascade of molecular/cellular events that accompany this disease.

Effects of harmaline on anxiety-related behavior in mice.

Harmaline (HA) is a beta-carboline commonly known to provoke motor alterations through activation of cells in the inferior olive. In addition, this pharmacological agent also induces cognitive disturbances such as motor and spatial learning impairments. In order to complete and extend these data, we examined the effects of this drug on state anxiety in mice, employing elevated plus maze test. We report here that lower doses of harmaline (5-10 mg/kg) have anxiogenic since higher doses (20 mg/kg) have anxiolytic-like properties. Overall pattern of our behavioral results provides evidence that harmaline also acts on emotional reactivity in mice by influencing their decision making when placed in an anxiogenic situation.

Antinociceptive effects of Peganum harmala L. alkaloid extract on mouse formalin test.

PURPOSE: To evaluate the effect of Peganum harmala (Syrian rue) a wild-growing flowering plant belonging to the family Zygophylaceae and found abundantly in Iran on formalin-induced pain response in mice. METHODS: Total alkaloid extract was prepared from dry seeds of Peganum harmala. All doses of extract were dissolved in normal saline and administered intraperitoneally 30 minutes before formalin injection to the mouse paw. Nociception was recorded 0-5 (early phase, A) and 15-40 (late phase, B) minutes after formalin injection. The alkaloid extract was subjected to silica gel column chromatography using a linear gradient with a CHCl3-MeOH system and different fractions collected. The effective fraction in formalin test were further purified and isolated by preparative thin layer chromatography (TLC) and identified on the basis of nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis. RESULTS: Alkaloid extract in doses (mg/kg) used induced significant reduction in pain response when compared to control as follow: 16 (28.63%), 20 (59.15%), 24 (80.75%), 28 (90.14%) and 30 (100%) in the early phase and 20 (24.67%), 24 (59.93%), 28 (78.52%) and 30 (100%) in late phase. Observed responses in both phases of A and B were dose-dependent with r2 of 0.93 and 0.99 respectively. ED50 for phases of A and B were 27.87 and 24.63 mg/kg respectively (p<0.001 for all groups). CONCLUSION: Harmaline, the last step of extraction is the main effective antinociceptive agent of the Peganum harmala alkaloid extract.

Effects of rutin and harmaline on rat reflux oesophagitis.

1. This study was aimed at evaluating the effect of rutin and harmaline (1-methyl-7-methoxy-3,4-dihydro-beta-carboline) on the development of the surgically induced reflux oesophagitis, on gastric secretion, lipid peroxidation, polymorphonucleocytes (PMNs) accumulation, superoxide and hydroxyl radical production in PMNs, cytokine [interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha)] production in blood and [Ca2+]i mobilization in PMNs. 2. Rutin and harmaline significantly prevented the development of reflux oesophagitis and gastric secretion. Treatments of oesophagitis rats with rutin and harmaline inhibited lipid peroxidation, and myeloperoxidase (MPO) in the oesophagus in comparison with untreated rats. 3. Superoxide anion and hydrogen peroxide production in 1 microm formylmethionylleucylphenylalanine (fMLP)- or 0.1 microg ml-1N-phorbol 12-myristate 13-acetate (PMA)-activated PMNs was inhibited by rutin and harmaline in a dose-dependent fashion. Rutin and harmaline effectively scavenged the hydroxyl radical and hydrogen peroxide. Treatments of oesophagitis rats with rutin and harmaline inhibited IL-1beta production in the oesophagus in comparison with untreated rats, but TNF-alpha production was not affected by rutin and harmaline. The fMLP-induced elevation of [Ca2+]i was inhibited by rutin. 4. The results of this study suggest that rutin and harmaline may have beneficial protective effects against reflux oesophagitis by the inhibition of gastric acid secretion, oxidative stress, inflammatory cytokine production (i.e. IL-1beta), and intracellular calcium mobilization in PMNs in rats.

Peganum harmala: its use in certain dermatoses.

The extract of Peganum harmala (Rutaceae) was used topically to treat certain dermatoses of inflammatory nature. Results were encouraging and proved the antibacterial, antifungal, antipruritic and probably antiprotozoal effects of the extract.