Fumaria vaillantii extract protects PC12 cells against neurotoxicity induced by 6-OHDA.

BACKGROUND: Parkinson's disease is a neurological disorder caused by the loss of dopaminergic neurons in the midbrain. Various mechanisms are involved in the incidence of the disease including oxidative stress. Several herbs and natural products may interfere with the oxidative-stress pathway due to their antioxidant effects. OBJECTIVE: Herein, we aimed to investigate the neuroprotective role of F. vaillantii extract on Parkinson's in vitro and in vivo model owing to the presence of the bioactive agents with antioxidant properties. METHODS: In vitro experments showed that 6-hydroxydopamine could induce toxicity in PC12 cells. The impact of F. vaillantii extract on cell viability was measured by using MTT assay. Nuclear morphological changes were qualitatively evaluated employing Hoechst staining. The antioxidant activity of the extract was determined by ROS and lipid peroxidation assays. Tyrosine hydroxylase protein expression was measured by western blotting in PC12 cells. For in vivo study, movement parameters were evaluated. RESULTS: The results indicated that 75 µΜ of 6-OHDA induced 50% toxicity in PC12 cells for 24 h. Following post-treatment with F. vaillantii extract (0.1 mg/ml) for 72 h, we observed that the extract effectively prevented cell toxicity induced by 6-OHDA and reduced the apoptotic cell population. Furthermore, the extract attenuated the ROS level, lipid peroxidation and increased protein expression of TH after 72 h of treatment. In addition, oral administration of 300 mg/kg of F. vaillantii extract for 14 days improved locomotor activity, catalepsy, bradykinesia, motor coordination and reduced the apomorphine-caused rotation in 6-OHDA- induced Parkinson's disease-like symptoms in male rats. CONCLUSION: The present study suggests a protective role for the extract of F. vaillantii against oxidative stress-induced cell damage in the PC12 cells exposed to neurotoxin 6-OHDA which was verified in in vivo model by reducing the motor defects induced by 6-OHDA. This extract could be a promising therapeutic agent for the prevention of PD progression.

Toll-Like Receptor 1/2 Postconditioning by the Ligand Pam3cys Tempers Posttraumatic Hyperexcitability, Neuroinflammation, and Microglial Response: A Potential Candidate for Posttraumatic Epilepsy.

Toll-like receptors (TLRs) are activated by endogenous molecules released from damaged cells and contribute to neuroinflammation following traumatic brain injury (TBI) and epilepsy. TLR1/2 agonist tri-palmitoyl-S-glyceryl-cysteine (Pam3cys) is a vaccine adjuvant with confirmed safety in humans. We assessed impact of TLR1/2 postconditioning by Pam3cys on epileptogenesis and neuroinflammation in male rats, 6, 24, and 48 h after mild-to-moderate TBI. Pam3cys was injected into cerebral ventricles 30 min after controlled cortical impact (CCI) injury. After 24 h, rats underwent chemical kindling by once every other day injections of pentylenetetrazole (PTZ) 35 mg/kg until development of generalized seizures. Number of intact neurons, brain expression of proinflammatory cytokine TNF-α, anti-inflammatory cytokine IL-10, and marker of anti-inflammatory microglia arginase1 (Arg1) were determined by immunoblotting. Astrocytes and macrophage/microglia activation/polarization at the contused area was assessed by double immunostaining with Iba1/Arg1, Iba1/iNOS and GFAP/iNOS, specific antibodies. The CCI-injured rats became kindled by less number of PTZ injections than sham-operated rats (9 versus 14 injections, p < 0.0001). Pam3cys treatment returned the accelerated rate of epileptogenesis in TBI state to the sham level. Pam3cys decreased neural death 48 h after TBI. It decreased TNF-α (6 h post-TBI, p < 0.01), and up-regulated IL-10 (p < 0.01) and Arg1 (p < 0.05) 48 h after TBI. The iNOS-positive cells decreased (p < 0.001) whereas Iba1/Arg1-positive cells enhanced (p < 0.01) after Pam3cys treatment. Pam3cys inhibits TBI-accelerated acquisition of seizures. Pam3cys reprograms microglia and up-regulates anti-inflammatory cytokines during the first few days after TBI. This capacity along with the clinical safety, makes Pam3cys a potential candidate for development of effective medications against posttraumatic epilepsy.

Biological Activity of Novel Pyrrole Derivatives as Antioxidant Agents Against 6-OHDA Induced Neurotoxicity in PC12 Cells.

Background: Neuroinflammation and oxidative stress are critical factors involved in the pathogenesis of Parkinson's disease (PD), the second most common progressive neurodegenerative disease. Additionally, lipid peroxidation end products contribute to inflammatory responses by activating pro-inflammatory genes. Lipid peroxidation occurs as a result of either the overproduction of intracellular reactive oxygen species (ROS) or the reaction of cyclooxygenases (COXs). Objectives: In this study, we examined the role of 1,5-diaryl pyrrole derivatives against the neurotoxic effects of 6-hydroxydopamine (6-OHDA) in a cellular model of PD. Methods: PC12 cells were pre-treated with compounds 2-(4-chlorophenyl)-5-methyl-1-(4-(trifluoromethoxy)phenyl)-1H-pyrrole (A), 2-(4-chlorophenyl)-1-(4-methoxyphenyl)-5-methyl-1H-pyrrole (B), and 1-(2-chlorophenyl)-2-(4-chlorophenyl)-5-methyl-1H-pyrrole (C), respectively, 24 h before exposure to 6-OHDA. We conducted various assays, including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT), ROS, and lipid peroxidation assays, Hoechst staining, Annexin V/PI, Western blotting analysis and ELISA method, to assess the neuroprotective effects of pyrrole derivatives on 6-OHDA-induced neurotoxicity. Results: Our results demonstrated that apoptosis induction was inhibited by controlling the lipid peroxidation process in the in vitro model following pre-treatment with compounds A, B, and, somehow, C. Furthermore, compounds A and C likely act by suppressing the COX-2/PGE2 pathway, a mechanism not attributed to compound B. Conclusions: These findings suggest that the novel synthetic pyrrolic derivatives may be considered promising neuroprotective agents that can potentially prevent the progression of PD.

The involvement of ventral hippocampal microglial cells, but not cannabinoid CB1 receptors, in morphine-induced analgesia in rats.

It is well known that glial cells are involved in pain processing. The purpose of the present study was to investigate the possible involvement of the ventral hippocampal (VH) glial cells in morphine-induced analgesia. A tail-flick apparatus was used to measure pain sensitivity in male Wistar rats that were bilaterally cannulated in the VH by stereotaxic surgery. The results showed that intraperitoneal (i.p.) administration of morphine (2.5-7.5 mg/kg) induced analgesia in a time-dependent manner. The blockade of the VH glial cell activation by bilateral microinjection of a glial inhibitor, minocycline (5-15 µg/rat) into the VH with an ineffective dose of morphine (2.5 mg/kg, i.p) significantly increased morphine analgesia. Considering that the endocannabinoid system via CB1 receptors play a crucial role in pain modulation, we also assessed the possible role of the VH cannabinoid CB1 receptors in the functional interaction between minocycline and morphine in acute pain. Our results indicated that intra-VH injection of the cannabinoid CB1 receptor agonist, arachidonylcyclopropylamide (ACPA; 4-12 ng/rat) had no effect on minocycline-induced potentiation of morphine analgesia. It should be considered that intra-VH microinjection of minocycline or ACPA by itself had no effect on tail-flick latency. Our findings suggest that the activation of the VH microglial cells may be involved in mediating pain sensation, because the inhibition of these cells by intra-VH injection of minocycline could potentiate morphine-induced analgesia. Although endocannabinoids have a regulatory role in glia function, the activation of CB1 receptors could not affect the potentiative effect of minocycline on morphine analgesia.