Table of Contents
ISRN Pharmacology
Volume 2013, Article ID 713060, 8 pages
Research Article

Anti-Inflammatory Effects of Hyptis albida Chloroform Extract on Lipopolysaccharide-Stimulated Peritoneal Macrophages

Departamento Sistemas Biológicos, Universidad Autónoma Metropolitana-Xochimilco, Calzada del Hueso 1100, Colonia Villa Quietud, 04960 Mexico, DF, Mexico

Received 4 June 2013; Accepted 2 July 2013

Academic Editors: E. M. Urbanska and S.-N. Wu

Copyright © 2013 Elizabeth Sánchez Miranda et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We examined the effects of a chloroform extract of Hyptis albida (CHA) on inflammatory responses in mouse lipopolysaccharide (LPS) induced peritoneal macrophages. Our findings indicate that CHA inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). During the process, levels of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), and nitric oxide (NO) increased in the mouse peritoneal macrophages; however, the extract suppressed them significantly. These results provide novel insights into the anti-inflammatory actions of CHA and support its potential use in the treatment of inflammatory diseases.

1. Introduction

Inflammation is an immediate response to many injuries produced by pathogens, noxious stimuli such as chemicals, or physical injury. Inflammation involves the activation and recruitment of phagocytes (macrophages, neutrophils), NK cells, the complement system, and the secretion of cytokines such as IL-1β, IL-6, and TNF-α by activated cells that are essential for the host defense system. Inflammatory disorders are treated using conventional anti-inflammatory drugs such as steroidal anti-inflammatory drugs and nonsteroidal anti-inflammatory drugs (NSAIDs) [1]. However, their prolonged use may produce adverse effects [2]. Thus, it is important to develop new anti-inflammatory agents with fewer adverse effects. Natural products can be a source of active metabolites that can serve as an alternate approach to anti-inflammatory drugs [3].

The genus Hyptis consists of approximately 400 species distributed from Southern United States to Argentina [4]. Plants in this genus have great economical and ethnopharmacological importance [5]. They have been used in folk medicine for the treatment of various disorders such as gastrointestinal disorders, skin infections, nasal congestion, fever, cramps, inflammation, and pain [58]. The genus Hyptis has many species that are important in Mexican folk medicine. In particular, Hyptis albida is commonly used in remedies for the treatment of gastrointestinal disturbances, skin infections, rheumatism, cramps, and muscular pains [9, 10]. Three triterpene lactones and five flavonoids have been isolated from an acetone extract [11] and the anti-inflammatory activity of a chloroform extract was reported by Pérez et al. [12]. The present investigation was carried out to assess the anti-inflammatory activity of a chloroform extract using murine macrophages stimulated with LPS.

2. Materials and Methods

2.1. Plant Material

Aerial parts of H. albida were collected in Guadalcazar, San Luis Potosi state, México. The plant was identified by taxonomist José García Pérez. A voucher specimen (SPLM 20419) was deposited in the Isidro Palacios Herbarium of the Universidad Autónoma de San Luis Potosi.

2.2. Preparation of the Extract

The shade-dried aerial parts were reduced to a powder, and 100 g of the powder sample was refluxed for 4 h with 400 mL chloroform. The extract was filtered, and the solvent was removed under reduced pressure (yield 5.3%). The extract showed positive results on Liebermann-Burchard, Tortelli-Jaffe, and Tschugaeff tests for terpenes and positive results on boric acid and citric acid for flavonoids [13].

2.3. Cell Culture

Macrophages were obtained from the peritoneal cavity of male BALB/c mice. Each mouse was injected with 1.5 mL of 4% thioglycollate in the peritoneal cavity. After 72 h a peritoneal lavage was performed with 10 mL cold 1x PBS buffer. The injected buffer was recovered and centrifuged to isolate cells. Cells were quantified using a Neubauer chamber and were cultured in plates for 24 h. Nonadherent cells were removed, and adherent cells were cultured in fresh medium. Peritoneal macrophages were maintained with RPMI supplemented with inactivated fetal bovine serum (FBS) at 10% and antibiotics, penicillin (100 units/mL) and streptomycin (100 μg/mL), in an atmosphere of 5% CO2 at 37°C.

2.4. Cell Viability Using a Crystal Violet Exclusion Assay

Cells (1 × 106 cells/well) were cultured in a 12-well plate for 24 h at 37°C in 5% CO2. After the medium was removed and replaced with fresh medium, CHA was added and incubated for 24 h. Viable cells were assessed with 0.4% crystal violet staining solution. Briefly, 200 μL crystal violet was added to each well, and the cells were incubated for 30 min at room temperature until the crystal violet solution was changed to acid (33%). The solution was removed, and the absorbance was measured at 540 nm in a microplate reader [14].

2.5. Determination of Nitric Oxide Production

Peritoneal macrophages were cultured at a density of 1 × 106 cells/well and incubated overnight. The macrophages were then pretreated with CHA at different noncytotoxic concentrations and incubated for 2 h. Then, LPS (1 μg/mL) was added followed by incubation for a further 24 h. The cell supernatant was collected for nitrite analysis, and the pellet cell was used for the PCR assay. Nitrite production, an indicator of NO synthesis, was measured in the supernatant of cultured macrophages using the Griess reaction [15]. Briefly, equal volumes (100 μL) of treated culture supernatant and Griess reagent (1% sulphanilamide, 0.1% NEDD, and 5% orthophosphoric acid) were mixed and incubated at room temperature for 5 min, and the absorbance was measured at 540 nm in a microplate reader. The amount of nitrite in the sample was determined using a sodium nitrite standard curve.

2.6. RNA Isolation and RT-PCR Analysis

Total RNA from LPS-treated macrophages was extracted with the TRIzol reagent, according to the manufacturers protocol. RNA was stored at 70°C until used. Reverse transcription of RNA (1 μg) was carried out with M-MuLV reverse transcriptase (Promega, WI, USA) and oligo-(dT)18 primers. PCR was performed in a reaction mixture containing the resulting cDNA, dNTP mixture (Promega), 10 pmol of target gene-specific primers, and 0.25 units of Taq DNA polymerase (Promega). Primers were designed using the Primer-BLAST software ( (Table 1). PCR products were electrophoresed on 2% agarose gels and stained with Gel-Red.

Table 1: List of sequences used for RT-PCR.
2.7. Measurement of Proinflammatory Cytokines (TNF-α and IL-6) Production

Peritoneal macrophages were cultured at a density of 2 × 106 cells/well and incubated overnight. Cell cultures were pretreated with different concentrations of CHA for 2 h thereafter; LPS (1 μg/mL) was then added followed by incubation for a further 24 h. The inhibitory effect of CHA on the production of proinflammatory cytokines (IL-6 and TNF-α) was determined in the supernatants. Quantities of cytokines were measured using a mouse ELISA kit (eBioscience).

2.8. Statistical Analysis

All values are expressed as the mean ± SEM. Differences between mean values of normally distributed data were assessed with one-way ANOVA (Newman Keuls t-test). Statistical significance was accepted at .

3. Results

3.1. Effects of H. albida Extract on Cell Viability

The potential cytotoxicity of CHA was evaluated using the crystal violet assay after incubating cells for 18 h in the absence or presence of LPS. The results showed that cell viabilities were not affected by the extract at the indicated concentrations of 25, 50, and 100 μg/mL (Figure 1). CHA did not show any cellular toxicity against peritoneal macrophages at these concentrations, which were then used in the experiments.

Figure 1: Effect of H. albida on the viability of peritoneal macrophages. The cells were treated with CHA in the absence or presence of LPS (1 μg/mL) for 24 h. The values represent the mean ± SEM of three independent experiments.
3.2. Inhibitory Effects of H. albida Extract on NO Production in Peritoneal Macrophages

Murine macrophages under basal conditions in culture media during incubation for 24 h produced μM NO. CHA did not significantly affect the basal level of NO ( μM). When cells were exposed to 1 μg/mL LPS for 24 h, the nitrite concentration increased markedly, to μM. CHA inhibited the production of NO after LPS stimulation in a dose-dependent manner by 36.62, 51.42, and 61.0% at 25, 50, and 100 μg/mL, respectively, (Figure 2). No significant difference in NO level was found between resting cells and the cells treated with 100 μg/mL of CHA.

Figure 2: Effects of CHA at concentrations 25, 50, and 100 μg/mL on production of NO in LPS-stimulated peritoneal macrophages. The values are the mean ± SEM of three independent experiments. ** LPS versus basal and group extract, * versus LPS group.
3.3. Inhibitory Effects of H. albida Extract on iNOS and COX-2 mRNA Expression in LPS-Stimulated Peritoneal Macrophages

COX-2 and iNOS are important enzymes in inflammation. To understand whether CHA can inhibit LPS-induced mRNA expression of these enzymes, a semiquantitative RT-PCR was performed. The expression of iNOS and COX-2 mRNA increased markedly upon LPS stimulation for 24 h, and CHA inhibited their expression in a concentration-dependent manner. iNOS was inhibited 31.22, 67.0, and 94.37% at 25, 50 and 100 μg/mL, respectively (Figure 3(a)), and COX-2 by, 22.0, 63.3, and 96.97%, respectively, at the same concentrations (Figure 3(b)). These results suggest that suppression of iNOS mRNA was responsible for the inhibitory effect of CHA on LPS-stimulated NO production.

Figure 3: Effect of CHA on LPS-induced mRNA expression of iNOS (a) and COX-2 (b) in peritoneal macrophages. The mean values ± SEM for three independent experiments are shown. ** versus basal and group extract, * versus LPS group.
3.4. H. albida Extract Inhibits LPS-Induced Production of TNF-α and IL-6 in Peritoneal Macrophages

We assessed the effects of CHA on the production of the proinflammatory cytokines, TNF-α, and IL-6, in LPS-exposed cells. Secretion of these cytokines was measured in the culture media of cells stimulated with 1 μg/mL LPS, alone or in combination with 25, 50, or 100 μg/mL CHA. Cytokine levels were measured by ELISA. Treatment of the cells with LPS resulted in significant increases in cytokine production relative to the control group. However, macrophages pretreated with CHA showed significantly reduced TNF-α, and IL-6 production (Figure 4). In particular, TNF-α was inhibited by CHA in LPS-stimulated macrophages (74.05%) at 100 μg/mL (Figure 4(a)). Moreover, IL-6 production was inhibited 15.0% at the same concentrations (Figure 4(b)). No significant difference was observed between resting cells and cells treated with 100 μg/mL CHA.

Figure 4: Effects of the extract of CHA on the (a) TNF-α and (b) IL-6 production in the peritoneal macrophages. Concentration in the supernatants was determined by ELISA. The results are the mean values  ± SEM for three independent experiments. ** versus basal and group extract, * versus LPS group.
3.5. Effects of CHA on mRNA Expression of TNF-α and IL-6 in LPS-Stimulated Macrophages

RT-PCR was performed to determine whether CHA reduced the expression of these cytokines at the mRNA levels. The levels of TNF-α and IL-6 mRNA were upregulated markedly in response to LPS treatment (Figure 5). CHA inhibited the expression of both messengers significantly in a concentration-dependent manner. TNF-α was inhibited by 30.0, 64.5, and 93.53% at 25, 50, and 100 μg/mL, respectively (Figure 5(a)), and IL-6 mRNA expression was suppressed by 18.67, 64.25, and 80.67% at the same concentrations (Figure 5(b)).

Figure 5: Effect of CHA on LPS-induced mRNA expression of TNF-α (a) and IL-6 (b) in peritoneal macrophages. The results are mean values ± SEM for three independent experiments. ** versus basal and group extract, * versus LPS group.

4. Discussion

Natural products play a significant role in drug discovery and development. The search for natural products with anti-inflammatory activity has increased markedly in recent years. H. albida is member of the Lamiaceae family, is restricted to the Pacific drainage of Mexico, and ranges from southwestern Sonora to central Guerrero. It is the medicinal plant used traditionally to treat various types of diseases [16].

Inflammation is a normal physiological and immune response to tissue injury and occurs when the human body attempts to counteract potentially injurious agents, such as invading bacteria, viruses, and other pathogens [17]. Macrophages play an important role in triggering inflammation during pathological conditions by overproducing inflammatory mediators, through the upregulation of inducible genes that contribute to inflammatory responses [18, 19]. LPS is an endotoxin, an integral outer membrane component of gram-negative bacteria. It induces the production of proinflammatory cytokines, NO, and prostaglandins (PGs) in macrophages [20]. Thus, therapeutic agents that inhibit the biosynthesis of these mediators may be useful for relieving proinflammatory conditions.

Proinflammatory mediators, such as NO and PGE2, are generated via iNOS and COX-2, respectively [21]. NO is a signaling molecule and has been shown to have multiple physiological effects on various organ systems. Some of the most prominent physiological actions of NO as a biological mediator include cGMP-dependent vasodilation, neural communication, host defense, inflammation, immune suppression, and blood clotting [22].

However, overproduction of NO during inflammation can activate nuclear factor kappa B (NF-κB) and induce the expression of proinflammatory mediators, which can promote inflammation by increasing cGMP levels and vascular permeability [22, 23]. NO can be toxic and can cause many diseases, such as cancer and atherosclerosis [24]. NO is produced from L-arginine by inducible NO synthase (iNOS). Overproduction of NO by iNOS can result in cytotoxicity and tissue damage [25]. iNOS is expressed in vascular smooth muscle cells, macrophages, and hepatocytes in response to immune-modulating molecules, such as LPS, interleukin (IL)-1, interferon gamma (IFN-γ), tumor growth factor beta (TGF-β), and proinflammatory cytokines [22, 2628]. Thus, inhibition of NO production by the downregulation of iNOS in macrophages is a significant therapeutic strategy in the development of anti-inflammatory agents. In this study we demonstrated that CHA inhibited NO production significantly in LPS-stimulated macrophages (Figure 2), this action appears to involve the inhibition of iNOS gene overexpression (Figure 3(a)).

On the other hand, COX-2 has an important role in the conversion of arachidonic acid to prostaglandins, especially PGE2, a mediator that can result in acute and chronic inflammation [2931]. The inhibition of COX-2 is clinically relevant because the resulting PG production is thought to be responsible for the antipyretic, anti-inflammatory, and analgesic proprieties of AINEs [32]. COX-2 is certainly a pivotal enzyme in inflammation, and inhibitors of COX-2 are being developed to obtain safer anti-inflammatory drugs. Many studies have demonstrated that compounds that selectively inhibit COX-2 produce less damage to the gastric mucus [1]. Our data also showed the inhibitory effects of CHA on COX-2 mRNA expression in LPS-stimulated macrophages (Figure 3(b)).

TNF-α and IL-6 are small secreted proteins that mediate and regulate immunity and inflammation. Both cytokines are derived mainly from activated macrophages. TNF-α has an important role in the immune response and has the ability to prevent infections and to keep inflammation locally circumscribed, but inappropriate or excessive production of TNF-α can be harmful [33]. Secreted TNF-α further induces cells to release IL-1β and IL-6 [34]. IL-6 is one of the most common inflammatory cytokines [35]; it can amplify the inflammatory cascade and cause injury [36, 37]. Moreover, both TNF-α and IL-6 are involved in the inflammatory response occurring in the vascular endothelial cells and promote the initiation and evolution of atherosclerosis by causing endothelial cells to express adhesion molecules and induced endothelial dysfunctions [3840]. Here, we observed that CHA could suppress the production of TNF-α and IL-6 from LPS-activated macrophages (Figure 4). Furthermore, CHA may inhibit the mRNA overexpression of both cytokines at the pre-translational level (Figure 5).

The chemical composition of the Lamiaceae family, especially the Hyptis genus, is remarkably variable, as they contain compounds such as terpenes, flavonoids, lactones, lignans, phenolic derivatives, and steroids [41]. It is reasonable to assume that the anti-inflammatory activity observed in extract of H. albida is due to the synergistic action of many components. Chemical analyses have revealed that the composition of H. albida extract consists of flavonoids and triterpenoids including betulinic, ursolic, oleanolic, and acetyl oleanic acids, and these compounds exhibit a variety of interesting medicinal properties [11].

Many terpenoids and flavonoids possess anti-inflammatory activities in various animal models of inflammation. Many investigators have proposed cellular mechanisms of action explaining the in vivo anti-inflammatory activities of these compounds. The terpenoid ursolic acid is found in many plants and is known to have anti-inflammatory activity [42]. Several authors have reported that ursolic acid suppresses the expression of the proinflammatory enzymes, COX-2 and iNOS [43], and inhibits the production of NO in macrophages [44] and NF-κB activation [45]. Some studies have indicated that some terpenoids have gastroprotective activity that involves reinforcement of defensive factors in the gastric mucosa [46]. On the other hand, flavonoids modulate the activities of arachidonic acid (AA) metabolizing enzymes such as phospholipase A2 (PLA2) [47, 48], COX-2 [49], and lipoxygenase (LOX) [5052] and iNOS [53]. Flavone and several amino-substituted flavones were reported to inhibit NO production [54, 55]. The production of some cytokines, such as IL-1, IL-6, and TNF-α, was inhibited by flavonoids in LPS-treated human blood monocytes and RAW 264.7 cells [56, 57].

In conclusion, we demonstrate that CHA is a potent inhibitor of inflammation. It inhibited the release of inflammatory mediators from macrophages and suppressed the overexpression of relevant genes. Further studies are underway to isolate the active components from H. albida and characterize their mechanism of action.


The authors acknowledge the financial support of the Instituto de Ciencia y Tecnología del Distrito Federal (Project no. 3410766) and Fortalecimiento de los Cuerpos Académicos Subsecretaria de Educación Superior Programa de Mejoramiento del Profesorado (clave UAM-X-CA-25).


  1. R. Gautam and S. M. Jachak, “Recent developments in anti-inflammatory natural products,” Medicinal Research Reviews, vol. 29, no. 5, pp. 767–820, 2009. View at Publisher · View at Google Scholar · View at Scopus
  2. M. C. Allison, A. G. Howatson, C. J. Torrance, F. D. Lee, and R. I. Russell, “Gastrointestinal damage associated with the use of nonsteroidal antiinflammatory drugs,” The New England Journal of Medicine, vol. 327, no. 11, pp. 749–754, 1992. View at Google Scholar · View at Scopus
  3. M. S. Butler, “Natural products to drugs: natural product derived compounds in clinical trials,” Natural Product Reports, vol. 22, no. 2, pp. 162–195, 2005. View at Publisher · View at Google Scholar · View at Scopus
  4. R. M. Harley, “Revision of generic limits in Hyptis Jacq. (Labiatae) and its allies,” Botanical Journal of the Linnean Society, vol. 98, no. 2, pp. 87–95, 1988. View at Publisher · View at Google Scholar
  5. C. R. P. Franco, Â. R. Antoniolli, A. G. Guimarães et al., “Bioassay-guided evaluation of antinociceptive properties and chemical variability of the essential oil of Hyptis fruticosa,” Phytotherapy Research, vol. 25, no. 11, pp. 1693–1699, 2011. View at Publisher · View at Google Scholar · View at Scopus
  6. M. D. Bispo, R. H. V. Mourão, E. M. Franzotti et al., “Antinociceptive and antiedematogenic effects of the aqueous extract of Hyptis pectinata leaves in experimental animals,” Journal of Ethnopharmacology, vol. 76, no. 1, pp. 81–86, 2001. View at Publisher · View at Google Scholar · View at Scopus
  7. A. X. Bueno, A. T. S. Moreira, F. T. Silva, C. S. Estevam, and M. Marchioro, “Effects of the aqueous extract from Hyptis pectinata leaves on rodent central nervous system,” Revista Brasileira De Farmacognosia, vol. 16, no. 3, pp. 317–323, 2006. View at Publisher · View at Google Scholar
  8. C. R. P. Franco, P. B. Alves, D. M. Andrade et al., “Essential oil composition and variability in Hyptis fruticosa,” Brazilian Journal of Pharmacognosy, vol. 21, no. 1, pp. 24–32, 2011. View at Publisher · View at Google Scholar · View at Scopus
  9. M. Martínez, Catálogo De Nombres Vulgares Y Científicos De Plantas Mexicanas, Fondo de Cultura Económica, México, 1979.
  10. J. L. Díaz, Uso De Las Plantas Medicinales De México, Instituto Mexicano para el Estudio de las Plantas Medicinales A.C., México, 1976.
  11. R. Pereda-Miranda and G. Delgado, “Triterpenoids and flavonoids from Hyptis albida,” Journal of Natural Products, vol. 53, no. 1, pp. 182–185, 1990. View at Google Scholar · View at Scopus
  12. S. Pérez, B. L. Hernández, M. A. Zavala, G. E. Morales, and N. Cárdenas, “Antiinflammatory activity of Hyptis albida,” Journal of Medicinal Plants Research, vol. 6, no. 43, pp. 5582–5585, 2012. View at Google Scholar
  13. X. A. Domínguez, Métodos De Investigación Fitoquímica, Ed Limusa México, 1973.
  14. A. Elmann, S. Mordechay, H. Erlank, A. Telerman, M. Rindner, and R. Ofir, “Anti-Neuroinflammatory effects of the extract of Achillea fragrantissima,” BMC Complementary and Alternative Medicine, vol. 11, article 98, 2011. View at Publisher · View at Google Scholar · View at Scopus
  15. K. S. Ahn, E. J. Noh, H. L. Zhao, S. H. Jung, S. S. Kang, and Y. S. Kim, “Inhibition of inducible nitric oxide synthase and cyclooxygenase II by Platycodon Grandiflorum saponins via suppression of nuclear factor-κB activation in RAW 264.7 cells,” Life Sciences, vol. 76, no. 20, pp. 2315–2328, 2005. View at Publisher · View at Google Scholar · View at Scopus
  16. A. Sánchez-González, D. Granados-Sánchez, and R. Simón-Nabor, “Medicinal uses of plants by the otomi towership nicolas flores, hidalgo México,” Revista Chapingo Series Horticulture, vol. 14, no. 3, pp. 271–279, 2008. View at Google Scholar
  17. N. T. Dung, V. K. Bajpai, J. I. Yoon, and S. C. Kang, “Anti-inflammatory effects of essential oil isolated from the buds of Cleistocalyx operculatus (Roxb.) Merr and Perry,” Food and Chemical Toxicology, vol. 47, no. 2, pp. 449–453, 2009. View at Publisher · View at Google Scholar · View at Scopus
  18. D. B. Reddy and P. Reddanna, “Chebulagic acid (CA) attenuates LPS-induced inflammation by suppressing NF-κB and MAPK activation in RAW 264.7 macrophages,” Biochemical and Biophysical Research Communications, vol. 381, no. 1, pp. 112–117, 2009. View at Publisher · View at Google Scholar · View at Scopus
  19. P.-H. Park, H. S. Kim, X. Y. Jin et al., “KB-34, a newly synthesized chalcone derivative, inhibits lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 macrophages via heme oxygenase-1 induction and blockade of activator protein-1,” European Journal of Pharmacology, vol. 606, no. 1–3, pp. 215–224, 2009. View at Publisher · View at Google Scholar · View at Scopus
  20. S.-I. Kanno, A. Shouji, A. Tomizawa et al., “Inhibitory effect of naringin on lipopolysaccharide (LPS)-induced endotoxin shock in mice and nitric oxide production in RAW 264.7 macrophages,” Life Sciences, vol. 78, no. 7, pp. 673–681, 2006. View at Publisher · View at Google Scholar · View at Scopus
  21. I. Posadas, M. C. Terencio, I. Guillén et al., “Co-regulation between cyclo-oxygenase-2 and inducible nitric oxide synthase expression in the time-course of murine inflammation,” Naunyn-Schmiedeberg's Archives of Pharmacology, vol. 361, no. 1, pp. 98–106, 2000. View at Publisher · View at Google Scholar · View at Scopus
  22. S. Moncada, R. M. J. Palmer, and E. A. Higgs, “Nitric oxide: physiology, pathophysiology, and pharmacology,” Pharmacological Reviews, vol. 43, no. 2, pp. 109–142, 1991. View at Google Scholar · View at Scopus
  23. D. Salvemini, Z.-Q. Wang, P. S. Wyatt et al., “Nitric oxide: a key mediator in the early and late phase of carrageenan-induced rat paw inflammation,” British Journal of Pharmacology, vol. 118, no. 4, pp. 829–838, 1996. View at Google Scholar · View at Scopus
  24. K. L. Davis, E. Martin, I. V. Turko, and F. Murad, “Novel effects of nitric oxide,” Annual Review of Pharmacology and Toxicology, vol. 41, pp. 203–236, 2001. View at Publisher · View at Google Scholar · View at Scopus
  25. A. R. Amin, P. Vyas, M. Attur et al., “The mode of action of aspirin-like drugs: effect on inducible nitric oxide synthase,” Proceedings of the National Academy of Sciences of the United States of America, vol. 92, no. 17, pp. 7926–7930, 1995. View at Publisher · View at Google Scholar · View at Scopus
  26. D. C. Rockey, J. J. Chung, C. M. McKee, and P. W. Noble, “Stimulation of inducible nitric oxide synthase in rat liver by hyaluronan fragments,” Hepatology, vol. 27, no. 1, pp. 86–92, 1998. View at Publisher · View at Google Scholar · View at Scopus
  27. Q. Li and I. M. Verma, “NF-κB regulation in the immune system,” Nature Reviews Immunology, vol. 2, no. 10, pp. 725–734, 2002. View at Publisher · View at Google Scholar · View at Scopus
  28. S. F. Liu and A. B. Malik, “NF-κB activation as a pathological mechanism of septic shock and inflammation,” American Journal of Physiology, vol. 290, no. 4, pp. L622–L645, 2006. View at Publisher · View at Google Scholar · View at Scopus
  29. W. L. Smith, R. Michael Garavito, and D. L. DeWitt, “Prostaglandin endoperoxide H syntheses (cyclooxygenases)-1 and -2,” The Journal of Biological Chemistry, vol. 271, no. 52, pp. 33157–33160, 1996. View at Google Scholar · View at Scopus
  30. M. K. O'Banion, V. D. Winn, and D. A. Young, “cDNA cloning and functional activity of a glucocorticoid-regulated inflammatory cyclooxygenase,” Proceedings of the National Academy of Sciences of the United States of America, vol. 89, no. 11, pp. 4888–4892, 1992. View at Publisher · View at Google Scholar · View at Scopus
  31. H. R. Herschman, “Prostaglandin synthase,” Biochimica et Biophysica Acta, vol. 1299, no. 1, pp. 125–140, 1996. View at Google Scholar · View at Scopus
  32. J. Clària, “Cyclooxigenase-2 biology,” Current Pharmaceutical Desing, vol. 9, pp. 2177–2190, 2003. View at Publisher · View at Google Scholar
  33. S. Zanotti, A. Kumar, and A. Kumar, “Cytokine modulation in sepsis and septic shock,” Expert Opinion on Investigational Drugs, vol. 11, no. 8, pp. 1061–1075, 2002. View at Publisher · View at Google Scholar · View at Scopus
  34. M. A. West, S. C. Seatter, J. Bellingham et al., “Mechanisms of reprogrammed macrophage endotoxin signal transduction after lipopolysaccharide pretreatment,” Surgery, vol. 118, no. 2, pp. 220–228, 1995. View at Publisher · View at Google Scholar · View at Scopus
  35. D. R. Hodge, E. M. Hurt, and W. L. Farrar, “The role of IL-6 and STAT3 in inflammation and cancer,” European Journal of Cancer, vol. 41, no. 16, pp. 2502–2512, 2005. View at Publisher · View at Google Scholar · View at Scopus
  36. S. Mukhopadhyay, J. R. Hoidal, and T. K. Mukherjee, “Role of TNFα in pulmonary pathophysiology,” Respiratory Research, vol. 7, article 125, 2006. View at Publisher · View at Google Scholar · View at Scopus
  37. T. Geiser, K. Atabai, P.-H. Jarreau, L. B. Ware, J. Pugin, and M. A. Matthay, “Pulmonary edema fluid from patients with acute lung injury augments in vitro alveolar epithelial repair by an IL-1β-dependent mechanism,” American Journal of Respiratory and Critical Care Medicine, vol. 163, no. 6, pp. 1384–1388, 2001. View at Google Scholar · View at Scopus
  38. P. M. Ridker, C. H. Hennekens, J. E. Buring, and N. Rifai, “C-reactive protein and other markers of inflammation in the prediction of cardiovascular disease in women,” The New England Journal of Medicine, vol. 342, no. 12, pp. 836–843, 2000. View at Publisher · View at Google Scholar · View at Scopus
  39. S. Verma, S.-H. Li, M. V. Badiwala et al., “Endothelin antagonism and interleukin-6 inhibition attenuate the proatherogenic effects of C-reactive protein,” Circulation, vol. 105, no. 16, pp. 1890–1896, 2002. View at Publisher · View at Google Scholar · View at Scopus
  40. B. Tarighi, T. Kurum, M. Demir, and S. N. Azcan, “The effects of nebivolol on fibrinolytic parameters in mild and moderate hypertensive patients,” Canadian Journal of Cardiology, vol. 23, no. 8, pp. 651–655, 2007. View at Google Scholar · View at Scopus
  41. D. Q. Falcão and F. S. Menezes, “Revisão etnofarmacológica, farmacológica e química do gênero Hyptis,” Revista Brasileira De Farmacognosia, vol. 84, no. 3, pp. 69–74, 2003. View at Google Scholar
  42. Y. M. Fan, L. Z. Xu, J. Gao et al., “Phytochemical and antiinflammatory studies on Terminalia catappa,” Fitoterapia, vol. 75, no. 3-4, pp. 253–260, 2004. View at Publisher · View at Google Scholar · View at Scopus
  43. N. Suh, T. Honda, H. J. Finlay et al., “Novel triterpenoids suppress inducible nitric oxide synthase (iNOS) and inducible cyclooxygenase (COX-2) in mouse macrophages,” Cancer Research, vol. 58, no. 4, pp. 717–723, 1998. View at Google Scholar · View at Scopus
  44. S. Y. Ryu, M.-H. Oak, S.-K. Yoon et al., “Anti-allergic and anti-inflammatory triterpenes from the herb of Prunella vulgaris,” Planta Medica, vol. 66, no. 4, pp. 358–360, 2000. View at Publisher · View at Google Scholar · View at Scopus
  45. S. Shishodia, S. Majumdar, S. Banerjee, and B. B. Aggarwal, “Ursolic acid inhibits nuclear factor-κB activation induced by carcinogenic agents through suppression of IκBα kinase and p65 phosphorylation: correlation with down-regulation of cyclooxygenase 2, matrix metalloproteinase 9, and cyclin D1,” Cancer Research, vol. 63, no. 15, pp. 4375–4383, 2003. View at Google Scholar · View at Scopus
  46. T. Ishikawa, R. D. S. Donatini, I. E. C. Diaz, M. Yoshida, E. M. Bacchi, and E. T. M. Kato, “Evaluation of gastroprotective activity of Plinia edulis (Vell.) Sobral (Myrtaceae) leaves in rats,” Journal of Ethnopharmacology, vol. 118, no. 3, pp. 527–529, 2008. View at Publisher · View at Google Scholar · View at Scopus
  47. S. J. Lee, R. H. Son, H. W. Chang, S. S. Kang, and H. P. Kim, “Inhibition of arachidonate release from rat peritoneal macrophage by biflavonoids,” Archives of Pharmacal Research, vol. 20, no. 6, pp. 533–538, 1997. View at Google Scholar · View at Scopus
  48. W. J. Kwak, T. C. Moon, C. X. Lin et al., “Papyriflavonol a from Broussonetia papyrifera inhibits the passive cutaneous anaphylaxis reaction and has a secretory phospholipase A2-inhibitory activity,” Biological and Pharmaceutical Bulletin, vol. 26, no. 3, pp. 299–302, 2003. View at Google Scholar · View at Scopus
  49. D. S. Jang, M. Cuendet, M. E. Hawthorne et al., “Prenylated flavonoids of the leaves of Macaranga conifera with inhibitory activity against cyclooxygenase-2,” Phytochemistry, vol. 61, no. 7, pp. 867–872, 2002. View at Publisher · View at Google Scholar · View at Scopus
  50. R. Landolfi, R. L. Mower, and M. Steiner, “Modification of platelet function and arachidonic acid metabolism by bioflavonoids. Structure-activity relations,” Biochemical Pharmacology, vol. 33, no. 9, pp. 1525–1530, 1984. View at Publisher · View at Google Scholar · View at Scopus
  51. T. Horie, M. Tsukayama, H. Kourai et al., “Syntheses of 5,6,7- and 5,7,8-trioxygenated 3',4'-dihydroxyflavones having alkoxy groups and their inhibitory activities against arachidonate 5-lipoxygenase,” Journal of Medicinal Chemistry, vol. 29, no. 11, pp. 2256–2262, 1986. View at Google Scholar · View at Scopus
  52. G. R. Reddy, N. Ueda, T. Hada et al., “A prenylflavone, artonin E, as arachidonate 5-lipoxygenase inhibitor,” Biochemical Pharmacology, vol. 41, no. 1, pp. 115–118, 1991. View at Publisher · View at Google Scholar · View at Scopus
  53. M. J. Laughton, P. J. Evans, M. A. Moroney, J. R. S. Hoult, and B. Halliwell, “Inhibition of mammalian 5-lipoxygenase and cyclo-oxygenase by flavonoids and phenolic dietary additives. Relationship to antioxidant activity and to iron ion-reducing ability,” Biochemical Pharmacology, vol. 42, no. 9, pp. 1673–1681, 1991. View at Publisher · View at Google Scholar · View at Scopus
  54. W. Krol, Z. P. Czuba, M. D. Threadgill, B. D. M. Cunningham, and G. Pietsz, “Inhibition of nitric oxide (NO·) production in murine macrophages by flavones,” Biochemical Pharmacology, vol. 50, no. 7, pp. 1031–1035, 1995. View at Publisher · View at Google Scholar · View at Scopus
  55. H. Sadowska-Krowicka, E. E. Mannick, P. D. Oliver et al., “Genistein and gut inflammation: role of nitric oxide,” Proceedings of the Society for Experimental Biology and Medicine, vol. 217, no. 3, pp. 351–357, 1998. View at Google Scholar · View at Scopus
  56. Y. Geng, B. Zhang, and M. Lotz, “Protein tyrosine kinase activation is required for lipopolysaccharide induction of cytokines in human blood monocytes,” Journal of Immunology, vol. 151, no. 12, pp. 6692–6700, 1993. View at Google Scholar · View at Scopus
  57. J. Y. Cho, P. S. Kim, J. Park et al., “Inhibitor of tumor necrosis factor-α production in lipopolysaccharide-stimulated RAW264.7 cells from Amorpha fruticosa,” Journal of Ethnopharmacology, vol. 70, no. 2, pp. 127–133, 2000. View at Publisher · View at Google Scholar · View at Scopus