ABSTRACT
BACKGROUND: Khaya grandifoliola (C.D.C.) stem bark, Cymbopogon citratus (Stapf) and Cryptolepis sanguinolenta (Lindl.) Schltr leaves are used in Cameroonian traditional medicine for the treatment of inflammatory diseases. Several studies have been performed on the biological activities of secondary metabolites extracted from these plants. However, to the best of our knowledge, the anti-neuro inflammatory and protective roles of the polysaccharides of these three plants have not yet been elucidated. This study aimed at investigating potential use of K. grandifoliola, C. sanguinolenta and C. citratus polysaccharides in the prevention of chronic inflammation. METHODS: Firstly, the composition of polysaccharide fractions isolated from K. grandifoliola stem bark (KGF), C. sanguinolenta (CSF) and C. citratus (CCF) leaves was assessed. Secondly, the cytotoxicity was evaluated on Raw 264.7 macrophages and U87-MG glioblastoma cell lines by the MTT assay. This was followed by the in vitro evaluation of the ability of KGF, CSF and CCF to inhibit lipopolysaccharides (LPS) induced overproduction of various pro-inflammatory mediators (NO, ROS and IL1ß, TNFα, IL6, NF-kB cytokines). This was done in Raw 264.7 and U87-MG cells. Finally, the in vitro protective effect of KGF, CSF and CCF against LPS-induced toxicity in the U87-MG cells was evaluated. RESULTS: CCF was shown to mostly contain sugar and no polyphenol while KGP and CSP contained very few amounts of these metabolites (≤ 2%). The three polysaccharide fractions were non-toxic up to 100 µg.mL- 1. All the polysaccharides at 10 µg/mL inhibited NO production, but only KGF and CCF at 12.5 µg/mL down-regulated LPS-induced ROS overproduction. Finally, 100 µg/mL LPS reduced 50% of U87 cell viability, and pre-treatment with the three polysaccharides significantly increased the proliferation. CONCLUSION: These results suggest that the polysaccharides of K. grandifoliola, C. citratus and C. sanguinolenta could be beneficial in preventing/treating neurodegenerative diseases in which neuroinflammation is part of the pathophysiology.
Subject(s)
Cryptolepis/chemistry , Cymbopogon/chemistry , Glioblastoma/drug therapy , Macrophages/drug effects , Meliaceae/chemistry , Neurodegenerative Diseases/drug therapy , Plant Extracts/pharmacology , Polysaccharides/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Glioblastoma/genetics , Glioblastoma/immunology , Glioblastoma/physiopathology , Humans , Lipopolysaccharides/adverse effects , Macrophages/immunology , Mice , NF-kappa B/genetics , NF-kappa B/immunology , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/immunology , Neurodegenerative Diseases/physiopathology , Plant Leaves/chemistry , RAW 264.7 Cells , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunologyABSTRACT
Neuropathic pain is caused by structural lesion leading to functional abnormalities in central and peripheral nervous system. Neuropathic pain in itself is not always a disease, as it arises due to consequences of other diseases like diabetes, spinal cord injury, degenerative neuronal diseases and cancer. Current strategies of neuropathic pain treatment have provided relief to the patients to some extent, but complete cure is still a distant dream. In the future, it is hoped that a combination of new and improved pharmaceutical developments combined with careful clinical trials and increased understanding of neuroplasticity will lead to improved and effective pain management strategies leading to improved quality of life. In this review we have discussed various therapeutic targets of neuropathic pain and their pathophysiological mechanisms. Current status of drugs used for treatment of neuropathic pain have also been discussed in the review.
Subject(s)
Neuralgia/therapy , Pain Management/methods , Pain Management/trends , Animals , Cytokines/metabolism , Humans , Ion Channels/drug effects , Ion Channels/physiology , Neuralgia/physiopathology , Pain Management/classification , Signal Transduction/drug effects , Signal Transduction/physiologyABSTRACT
We disclose the discovery of a novel series of tetrahydropyrido-pyrazoles that are potent inhibitors of tumour necrosis factor-alpha (TNF-α), nitric oxide and cannabinoid receptor subtype 1 (CB1). We report herein the synthesis and neuropharmacological screening results of the titled compounds in two acute pain and two neuropathic pain models in rodents. Particularly the analogue N-(4-bromophenyl)-3-tert-butyl-5-ethyl-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine-1-carboxamide (8a) exhibited pronounced acute antinociceptive efficacy, also being effective in chronic constriction injury (ED50 = 23.8 mg/kg) and partial sciatic nerve injury (ED50 = 29.0 mg/kg) models with CB1 receptor activity (IC50 = 49.6 nM) and inhibitory effect on TNF-α (86.4% inhibition at 100 mg/kg). These results suggest the importance of the development of this lead as multi-targeted treatment strategy for neuropathic pain.
