Natural Products Evaluated in Neuropathic Pain Models ‐ A Systematic Review

Abstract

Chronic pain conditions, such as neuropathic pain, are a common problem that poses a major challenge to health-care providers due to its complex natural history, unclear aetiology and poor response towards therapy. Despite the large number of drugs available, the adherence is limited by the large range of side effects and pharmacological ineffectiveness. Thus, the search for new chemical entities that can act as promising molecules to treat chronic pain conditions has emerged. The natural products remain as the most promising sources of new chemical entities with applicability for the medical approach. Hence, we performed a systematic review analysing pre-clinical studies shown to be promising in a possible applicability in neuropathic pain. The search terms neuropathic pain, phytotherapy and medicinal plants were used to retrieve English language articles in LILACS, PUBMED and EMBASE published until 10 April 2013. From a total of 1529 articles surveyed, 28 met the inclusion and exclusion criteria established. The main chemical compounds studied were flavonoids (28%), terpenes (17%), alkaloids (14%), phenols (10%), carotenoids (10%) and others (21%). The mostly described animal models for the study of neuropathic pain included were chronic constriction injury (CCI -32%), partial sciatic nerve ligation (PSNL -28%), streptozotocin -induced diabetic (28%), alcoholic neuropathy (3.5%), sodium monoiodoacetate (MIA -3.5%) and neuropathic pain induced by paclitaxel (3.5%). The opioids, serotonergic and cannabinoid systems are suggested as the most promising targets for the natural products described. Therefore, the data reviewed here suggest that these compounds are possible candidates for the treatment of chronic painful conditions, such as neuropathic pain.

The use of the antimicrobial peptide piscidin (PCD)-1 as a novel anti-nociceptive agent

“…In a review of 174 published trials, Finnerup et al (2010) reported that no available drug treatments are able to relieve all neuropathic pain conditions [25]. Therefore, therapeutic treatment of neuropathic syndromes remain challenging on account of their complex natural history, unclear etiology, and poor response to drugs [26]. The anti-epileptic drug gabapentin is widely used to treat neuropathic pain, and it effectively relieves allodynia, burning pain, shooting pain, and hyperesthesia [27].…”

Evaluation of the Anti-Inflammatory and Antinociceptive Effects of the Essential Oil from Leaves ofXylopia laevigatain Experimental Models

“…Unfortunately, we cannot isolate these terpenoids in EOX to test them separately. Even so, it is possible that the pharmacological properties, such as anti-inflammatory and analgesic, of EOX are related to the presence of terpenoid compounds [52–54]. …”

Inclusion of terpenes in cyclodextrins: Preparation, characterization and pharmacological approaches

“…Monoterpenes are commonly able to produce analgesic, antioxidant and antiinflammatory effects, including their ability to treat chronic pain (Guimaraes, Quintans & Quintans Júnior, 2013;Guimaraes, Serafini & Quintans-Junior, 2014;Quintans, Antoniolli, Almeida, Santana-Filho & Quintans-Junior, 2014). These compounds possess a poor oral absorption due to their extremely low aqueous solubility or their extensive pre-systemic metabolism and this may be responsible for the unfavorable pharmacokinetics of the molecule (Yadav, Suresh, Devi & Yadav, 2009).…”