1. Inflammation

Inflammation is a response of vascularized tissues to infections and tissue damage, and contributes to the beginning and progression of diseases such as Alzheimer, type 2

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and eproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

diabetes, obesity, stroke, and cancer [1, 2]. The symptomatology of inflammation is characterized by pain, redness, swelling, heat, and loss of function. Depending on the time of duration, inflammation might be categorized into acute and chronic. Acute inflammation is considered as a protective response and occurs within minutes, hours, or few days after exposure to infections and/or tissue damage. Acute inflammation is characterized by the exudation of fluid (edema), elevated blood flow, and migration of neutrophils [3]. Chronic inflammation occurs when the initial response fails to repair tissue damaged or when a noxious stimulus is persistent, and is characterized with more tissue destruction, fibrosis, long presence of lymphocytes [4]. Macrophages, dendritic cells, and mast cells initiate the inflammatory process secreting pro-inflammatory cytokines such as interleukin 6 (IL-6) and interleukin 8 (IL-8), tumor necrosis factor-α (TNF-α), and inducing the production of reactive oxygen species (ROS), which play an important role in the modulation of inflammation [5]. The long-term use of current drugs for the treatment of inflammation, including nonsteroidal anti-inflammatory drugs (NSAIDs), the disease-modifying anti-rheumatic drugs (DMARDs), and steroids display several undesirable side effects such as gastric ulcers, nephrotoxicity, and hepatotoxicity, among others [6]. The search of new anti-inflammatory agents with less side effects is highly desirable. Furthermore, the efficient treatment of inflammation may be an interesting and effective way to prevent chronic diseases like cancer.

murine macrophages stimulated with lipopolysaccharide (LPS). In addition, isocyperol reduced the serum levels of NO, PGE2, and IL-6 in LPS-induced septic shock in mice, via suppression of the NF-кB and STAT3 signaling pathways [14]. Dodonaea viscosa induces gastroprotective [15], antibacterial [16], analgesic, and anti-inflammatory activities [17, 18]. Hawtriwaic acid, an ent-clerodane diterpene, was isolated from D. viscosa and showed antiinflammatory activity on the murine ear edema induced with 12-O-tetradecanoylphorbol-13 acetate (TPA) by one or multiple applications. In both models, the compound diminished the edema [19]. Hawtriwaic acid at doses of 5, 10, and 20 mg/kg decreased knee inflammation in a murine model of monoarthritis induced with kaolin/carrageenan, by the reduction of serum levels of the pro-inflammatory interleukins Il-1β, IL-6, and TNF-α, and the increase in the serum levels of the anti-inflammatory interleukin IL-10 [20]. Ursolic acid, a pentacyclic triterpene found in many plant species, was identified for the first time in 1920 in the epicuticular waxes of apples. Ursolic acid exerts cytotoxic effects in various cancer cells by the inhibition of the STAT3 signaling pathway [21] and the induction of apoptosis [22]. Ursolic acid has protective effects on lung, kidney, liver, and brain, exerts anabolic effects on skeletal muscle [23], and induces antinociceptive activity in abdominal constriction test induced by acetic acid and the formalin test in mice [24]. Ursolic acid decreased the paw edema induced with carrageenan in rats [25], decreased the ear edema induced with Croton oil in mice [26], reduced the levels of iNOS, COX-2, IL-1β, IL-6, and TNF-α, and increased the level of IL-10 in

Terpenes from Natural Products with Potential Anti-Inflammatory Activity

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The sesquiterpenes, vernomelitensin and onopordopicrin, isolated from Onopordum illyricum and the triterpene, Sootepin F, obtained from Gardenia sootepensis, decreased each NF-

The pro-inflammatory enzymes: (1) inducible the nitric oxide synthase (iNOS), which is involved in the nitric oxide (NO) production, and the cyclooxygenase-2 (COX-2) involved in the prostaglandin production, are estimated in LPS-induced macrophages to evaluate the in vitro anti-inflammatory activity. IL-1 and TNF-α stimulate the production of NO. The inhibitory concentration 50 (IC50) for these two pro-inflammatory enzymes has only been reported in some studies. The sesquiterpenes hydroxycostunolide (IC50 = 0.68 μM), costunolide (IC50 0.3 μM), and artemorin (IC50 = 0.16 μM), obtained from Inula montana, showed similar or higher potency in the inhibition of NO, compared to that reported for the positive control dexamethasone (IC50 = 0.45–4.33 μM) [30]. Further studies are recommended to be performed with theses sesquiterpenes. Toxicological studies to guarantee their safety in long-term studies are also necessary. The in vivo studies evaluate swelling,

In the table is show the structure of 62 sesquiterpenes, 34 diterpenes, and 22 triterpenes with

anti-inflammatory activity, isolated from 44 plant species, 1 sponge, and 2 corals.

κB activity with IC50 values of 3.6, 8.6, and 20.3 μM, respectively [28, 29].

macrophages stimulated with LPS [27].

redness, and pain mainly in rodents.
