Anti-Inflammatory Iridoids of Botanical Origin

Abstract

Inflammation is a manifestation of a wide range of disorders which include; arthritis, atherosclerosis, Alzheimer’s disease, inflammatory bowel syndrome, physical injury and infection amongst many others. Common treatment modalities are usually non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, paracetamol, indomethacin and ibuprofen as well as corticosteroids such as prednisone. These however, may be associated with a host of side effects due to non-selectivity for cyclooxygenase (COX) enzymes involved in inflammation and those with selectivity may be highly priced. Thus, there is a continuing search for safe and effective anti-inflammatory molecules from natural sources. Research has confirmed that iridoids exhibit promising anti-inflammatory activity which may be beneficial in the treatment of inflammation. Iridoids are secondary metabolites present in various plants, especially in species belonging to the Apocynaceae, Lamiaceae, Loganiaceae, Rubiaceae, Scrophulariaceae and Verbenaceae families. Many of these ethnobotanicals have an illustrious history of traditional use alluding to their use to treat inflammation. Although iridoids exhibit a wide range of pharmacological activities such as cardiovascular, hepatoprotection, hypoglycaemic, antimutagenic, antispasmodic, anti-tumour, antiviral, immunomodulation and purgative effects this review will acutely focus on their anti-inflammatory properties. The paper aims to present a summary for the most prominent iridoid-containing plants for which anti-inflammatory activity has been demonstrated in vitro and / or in vivo.

Finishing lambs on a chicory-plantain mixture or a temperate grassbased pasture: live weight gain and gastrointestinal parasitism

“…Although there is interest in the anthelmintic properties of plantains, the evidence supporting a direct effect is scarce (Sievers and Nannig, 2006). However, important antimicrobial and anti-inflammatory effects have been found in iridoid glycosides from plantains, and these effects are even stronger in their degradation products (Viljoen et al, 2012). It could be hypothesized that bioactive metabolites from herbs (chicory and/or plantain) or their derivatives excreted in feces affected the GIN eggs (lower hatchability) or the intermediary stage larvae (L1, L2) in the fecal environment, impairing migration or nutrition and affecting parasite survival.…”

Effects of Veronica officinalis extract in the kidney of rats with induced sepsis

“…COX-2 expression is initiated by the response to proinflammatory stimuli through mitogen-activated protein kinase or NF-kB inflammatory signaling pathways [21].…”

Phytochemical Screening and Evaluation of Anti-Inflammatory Activity of Aerial Part Extracts of Plantago Major L.

“…They concluded that P. major extract, baicalein and aucubin, significantly inhibited the production of reactive oxygen species from the neutrophils. Numerous studies have reported that anti-inflammatory and analgesic activities of medicinal plants have been related the presence of tannins, flavonoids, alkaloids, phenolic compounds [40,41], and iridoid glycosides [42,43]. Therefore, the antiinflammatory activity observed in P. major may be due to the activity or activities of one compound or a combination of a number of compounds belongs to the different classes of compounds present in aerial parts of P. major [44].…”