Antinociceptive activities and the mechanisms of anti-inflammation of asiatic Acid in mice

ASIATIC ACID INFLUENCES GLUCOSE HOMEOSTASIS IN P. BERGHEI MURINE MALARIA INFECTED SPRAGUE-DAWLEY RATS

Background:

Glucose homeostasis derangement is a common pathophysiology of malaria whose aetiology is still controversial. The Plasmodium parasite, immunological and inflammatory responses, as well as chemotherapeutics currently used cause hypoglycaemia in malaria. Anti-parasitic and anti-disease drugs are required to combat malaria while ameliorating the pathophysiology of the infection. Asiatic acid has anti-hyperglycaemic, antioxidant, pro-oxidant properties useful in glucose homeostasis but its influence in malaria is yet to be reported. Here we present findings on the influence of asiatic acid on glucose metabolism in vivo using P. berghei-infected Sprague Dawley rats.

Materials and Methods:

Acute as well as sub-chronic studies were carried out in vivo where physicochemical properties and glucose homeostasis were monitored after administration of asiatic acid (10mg/kg) in both non-infected and infected animals. Glucose metabolism associated biochemical changes in malaria were also investigated.

Results:

In acute studies, asiatic acid improved oral glucose response while in the sub-chronic state it maintained food and water intake and suppressed parasitaemia. Normoglycaemic control was maintained in infected animals through insulin suppression and increasing glucagon secretion, in both acute and chronic studies. Asiatic acid administration curtailed lactate concentration towards normal.

Conclusion:

Per oral post-infection asiatic acid administration preserved drinking and eating habits, inhibited sickness behaviour while suppressing parasitaemia. Reciprocal relationship between insulin and glucagon concentrations was maintained influencing glucose homeostasis positively and inhibition of hyperlactaemia in malaria.

Abbreviations: ip -intraperitoneal, po -per oral, ig -intragastric, AA-Asciatic acid, OGTT-oral glucose tolerance test, OS-oxidative stress, ROS-reactive oxygen species, NO-nitric oxide, ONOO^- - peroxynitrite, BRU-Biomedical Research Unit, SD-Sprague Dawley,

Asiatic Acid Prevents the Deleterious Effects of Valproic Acid on Cognition and Hippocampal Cell Proliferation and Survival

Valproic acid (VPA) is commonly prescribed as an anticonvulsant and mood stabilizer used in the treatment of epilepsy and bipolar disorder. A recent study has demonstrated that VPA reduces histone deacetylase (HDAC) activity, an action which is believed to contribute to the effects of VPA on neural stem cell proliferation and differentiation which may explain the cognitive impairments produced in rodents and patients. Asiatic acid is a triterpenoid derived from the medicinal plant Centella asiatica. Our previous study has shown that Asiatic acid improves working spatial memory and increases cell proliferation in the sub granular zone of the hippocampal dentate gyrus. In the present study we investigate the effects of Asiatic acid in preventing the memory and cellular effects of VPA. Male Spraque-Dawley rats were orally administered Asiatic acid (30 mg/kg/day) for 28 days, while VPA-treated animals received injections of VPA (300 mg/kg) twice a day from Day 15 to Day 28 for 14 days. Spatial memory was determined using the novel object location (NOL) test and hippocampal cell proliferation and survival was quantified by immuostaining for Ki-67 and Bromodeoxyuridine (BrdU), respectively. The results showed that VPA-treated animals were unable to discriminate between objects in familiar and novel locations. Moreover, VPA significantly reduced numbers of Ki-67 and BrdU positive cells. These results indicate that VPA treatment caused impairments of spatial working memory, cell proliferation and survival in the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). However, these abnormalities were restored to control levels by co-treatment with Asiatic acid. These data demonstrate that Asiatic acid could prevent the spatial memory and neurogenesis impairments caused by VPA.

Pre-infection administration of asiatic acid retards parasitaemia induction in Plasmodium berghei murine malaria infected Sprague-Dawley rats

BACKGROUND

Malaria prevention has remained a critical area in the absence of efficacious vaccines against malaria. Drugs currently used as chemotherapeutics are also used in chemoprophylaxis increasing possible drug resistance. Asiatic acid is a natural phytochemical with oxidant, antioxidant and anti-inflammatory properties with emerging anti-malarial potential. The influence of asiatic acid administration prior to Plasmodium berghei infection of Sprague-Dawley rats on parasitaemia induction is here reported.

METHODS

Sprague-Dawley rats (90-120 g) were administered with asiatic acid (10 mg/kg) 48 h before intraperitoneal infection with P. berghei. Parasitaemia induction and progression, food and water intake as well as weight were compared to 30 mg/kg chloroquine-treated and infected control rats during sub-chronic studies (21 days).

RESULTS

Asiatic acid pre-infection administration preserved food and water intake as well as increase in percentage weight gain of infected animals. In pre-infection treated animals, the pre-patent period was extended to day 6 from 72 h. Asiatic acid suppressed parasitaemia while oral chloroquine (30 mg/kg) did not influence malaria induction.

CONCLUSIONS

Per-oral, pre-infection, asiatic acid administration influenced parasitaemia patency and parasitaemia progression, food, water, and weight gain percentage. This may suggest possible chemoprophylaxis effects of asiatic acid in malaria.

Anti-glioma activity and the mechanism of cellular uptake of asiatic acid-loaded solid lipid nanoparticles

Asiatic acid (AA), a pentacyclic triterpene found in Centella Asiatica, has shown neuroprotective and anti-cancer activity against glioma. However, owing to its poor aqueous solubility, effective delivery and absorption across biological barriers, in particular the blood brain barrier (BBB), are challenging. Solid lipid nanoparticles (SLNs) have shown a promising potential as a drug delivery system to carry lipophilic drugs across the BBB, a major obstacle in brain cancer therapy. Nevertheless, limited information is available about the cytotoxic mechanisms of nano-lipidic carriers with AA on normal and glioma cells. This study assessed the anti-cancer efficacy of AA-loaded SLNs against glioblastoma and their cellular uptake mechanism in comparison with SVG P12 (human foetal glial) cells. SLNs were systematically investigated for three different solid lipids; glyceryl monostearate (MS), glyceryl distearate (DS) and glyceryl tristearate (TS). The non-drug containing MS-SLNs (E-MS-SLNs) did not show any apparent toxicity towards normal SVG P12 cells, whilst the AA-loaded MS-SLNs (AA-MS-SLNs) displayed a more favourable drug release profile and higher cytotoxicity towards U87 MG cells. Therefore, MS-SLNs were chosen for further in vitro studies. Cytotoxicity studies of SLNs (± AA) were performed using MTT assay where AA-SLNs showed significantly higher cytotoxicity towards U87 MG cells than SVG P12 normal cells, as confirmed by flow cell cytometry. Cellular uptake of SLNs also appeared to be preferentially facilitated by energy-dependent endocytosis as evidenced by fluorescence imaging and flow cell cytometry. Using the Annexin V-PI double staining technique, it was found that these AA-MS-SLNs displayed concentration-dependent apoptotic activity on glioma cells, which further confirms the potential of exploiting these AA-loaded MS-SLNs for brain cancer therapy.

Asiatic acid inhibits cardiac hypertrophy by blocking interleukin-1β-activated nuclear factor-κB signaling in vitro and in vivo

BACKGROUND

Activated interleukin (IL)-1β signaling pathway is closely associated with pathological cardiac hypertrophy. This study investigated whether asiatic acid (AA) could inhibit IL-1β-related hypertrophic signaling, and thus suppressing the development of cardiac hypertrophy.

METHODS

Transverse aortic constriction (TAC) induced cardiac hypertrophy in C57BL/6 mice and cultured neonatal cardiac myocytes stimulated with IL-1β were used to evaluate the role of AA in cardiac hypertrophy. The expression of atrial natriuretic peptide (ANP) was evaluated by quantitative polymerase chain reaction (qPCR) and the nuclear factor (NF)-κB binding activity was measured by electrophoretic mobility shift assays (EMSA).

RESULTS

AA pretreatment significantly attenuated the IL-1β-induced hypertrophic response of cardiomyocytes as reflected by reduction in the cardiomyocyte surface area and the inhibition of ANP mRNA expression. The protective effect of AA on IL-1β-stimulated cardiomyocytes was associated with the reduction of NF-κB binding activity. In addition, AA prevented TAC-induced cardiac hypertrophy in vivo. It was found that AA markedly reduced the excessive expression of IL-1β and ANP, and inhibited the activation of NF-κB in the hypertrophic myocardium.

CONCLUSIONS

Our data suggest that AA may be a novel therapeutic agent for cardiac hypertrophy. The inhibition of IL-1β-activated NF-κB signaling may be the mechanism through which AA prevents cardiac hypertrophy.

Asiatic acid inhibits left ventricular remodeling and improves cardiac function in a rat model of myocardial infarction

Left ventricular remodeling results in cardiac dysfunction and accounts for the majority of the morbidity and mortality following myocardial infarction (MI). The aim of the present study was to investigate the effect of asiatic acid (AA) on cardiac function and left ventricular remodeling in a rat model of MI and explore the underlying mechanisms. Rats were subjected to coronary artery ligation to model MI and orally treated with AA. After 4 weeks, cardiac function was assessed by echocardiography. Cardiomyocyte cross-sectional area was recorded, and the expression levels of a number of inflammatory cytokines were detected using ELISA. The degree of interstitial fibrosis was determined by evaluating the mRNA expression levels of collagen II and III. Western blot analysis was performed to detect the expression levels of total and phosphorylated p38 MAPK and ERK1/2, to investigate whether they are involved in the mechanism underlying the effect of AA on the heart. Rats subjected to MI displayed significantly impaired cardiac function compared with those subjected to a sham procedure, while this change was reversed by treatment with AA. Furthermore, AA markedly inhibited cardiac hypertrophy, reduced the mRNA expression levels of inflammatory cytokines and decreased interstitial fibrosis in the infarct border zone of MI model rats compared with those in vehicle-treated MI model rats. Furthermore, the phosphorylation of p38 MAPK and ERK1/2 was blocked by AA in the MI rats but not in the sham rats. In summary, AA treatment preserved cardiac function and inhibited left ventricular remodeling, potentially by blocking the phosphorylation of p38 MAPK and ERK1/2 in the infarct border zone of the ischemic myocardium, indicating that AA may be a novel candidate for development as a therapy for MI.

Seasonal Variation of Triterpenes and Phenolic Compounds in Australian Centella asiatica (L.) Urb

INTRODUCTION

Specific triterpenes, phenolic acids and flavonoids in Centella asiatica have been found to be bioactive. Harvesting the plant when these putative bioactive compounds are at their highest concentrations would provide consistency in their chemical profile, thus ensuring the quality and efficacy of derived medicinal products.

OBJECTIVE

The aim of the study was to determine the impact of harvesting time on the contents of major triterpenoid and phenolic compounds in C. asiatica.

METHODOLOGY

Australian C. asiatica was collected from a designated area in different months. The principal triterpenes (asiaticoside, madecassoside, asiatic acid and madecassic acid), flavonoid compounds (rutin, quercetin and kaempferol) and chlorogenic acid were quantitatively determined by HPLC-DAD analysis.

RESULTS

Triterpenoid, kaempferol and chlorogenic acid content showed significant variation (p < 0.05) in different collecting months. The total content of the four triterpenes reached its highest levels in January and February (83.15 ± 0.16 mg/g and 78.41 ± 0.16 mg/g, respectively), the summer season of the southern hemisphere, and their lowest values in winter (June) and spring (October) seasons (35.65 ± 0.20 and 35.50 ± 0.55 mg/g, respectively). Similarly, the contents of chlorogenic acid and kaempferol were the highest in December and January (1.62 ± 0.01 and 0.33 ± 0.01 mg/g, respectively), and the lowest in June (0.06 ± 0.01 and 0.09 ± 0.01 mg/g, respectively).

CONCLUSION

The results indicate that harvesting C. asiatica in summer returns the highest yield of the target triterpenoids, kaempferol and chlorogenic acid.

Bee venom ameliorates lipopolysaccharide-induced memory loss by preventing NF-kappaB pathway

Background

Accumulation of beta-amyloid and neuroinflammation trigger Alzheimer’s disease. We previously found that lipopolysaccharide (LPS) caused neuroinflammation with concomitant accumulation of beta-amyloid peptides leading to memory loss. A variety of anti-inflammatory compounds inhibiting nuclear factor kappaB (NF-κB) activation have showed efficacy to hinder neuroinflammation and amyloidogenesis. We also found that bee venom (BV) inhibits NF-κB.

Methods

A mouse model of LPS-induced memory loss used administration of BV (0.8 and 1.6 μg/kg/day, i.p.) to ICR mice for 7 days before injection of LPS (2.5 mg/kg/day, i.p.). Memory loss was assessed using a Morris water maze test and passive avoidance test. For in vitro study, we treated BV (0.5, 1, and 2 μg/mL) to astrocytes and microglial BV-2 cells with LPS (1 μg/mL).

Results

We found that BV inhibited LPS-induced memory loss determined by behavioral tests as well as cell death. BV also inhibited LPS-induced increases in the level of beta-amyloid (Aβ), β-and γ-secretases activities, NF-κB and its DNA-binding activity and expression of APP, and BACE1 and neuroinflammation proteins (COX-2, iNOS, GFAP and IBA-1) in the brain and cultured cells. In addition, pull-down assay and molecular modeling showed that BV binds to NF-κB.

Conclusions

BV attenuates LPS-induced amyloidogenesis, neuroinflammation, and therefore memory loss via inhibiting NF-κB signaling pathway. Thus, BV could be useful for treatment of Alzheimer’s disease.

Analgesic, Anti- inflammatory, Anti- lipoxygenase Activity and Characterization of Three Bioactive Compounds in the Most Active Fraction of Leptadenia reticulata (Retz.)Wight & Arn. - A Valuable Medicinal Plant

Leptadenia reticulata was reported to be used for several medicinal purposes. The present study was undertaken to evaluate anti-inflammatory, analgesic and lipid peroxidation inhibition activities of L. reticulata. The anti-inflammatory assay was performed by λ-carrageenan and formalin induced paw edema test. Pro inflammatory mediators (IL2, IL6, TNF-α) in serum of treated and control organism were analyzed by quantitative ELISA. Lipid peroxidation inhibition was measured by thiobarbituric acid reactive substances (TBARS) assay. Analysis of the most active fraction revealed the presence of one phenolic compound (p-coumaric acid), two flavonoids (rutin and quercetin) which also determined quantitatively. The ethyl acetate fraction at 600 mg/Kg significantly inhibited λ-carrageenan and formalin induced paw edema by 60.59% and 59.24% respectively. Notable reduction in percentage of writhing (76.25%), induced by acetic acid signifies the potent analgesic activity. Lower level of pro-inflammatory cytokines (IL-2, IL-6, TNF-α) in serum at the 4(th) hour of λ-Carrageenan injection indicated the inhibition of cyclooxigenase-2 (Cox-2), Nitric oxide (NO) and release of prostaglandin to prevent inflammation. The study also demonstrated the decrease in malonaldehyde (MDA) concentration which revealed the lipid peroxidation inhibition potential of the plant. Our finding provides evidence for potent biological activities in tested model which is supported by its characterized bioactive compounds and ethnomedicinal relevance.

Nepalese traditional medicine and symptoms related to Parkinson's disease and other disorders: Patterns of the usage of plant resources along the Himalayan altitudinal range

ETHNOPHARMACOLOGICAL RELEVANCE

Nepal is a hotspot for cultural and biological diversities. The tremendous diversity of ecosystems and climates and the blend of medicinal practices inherited from Ayurvedic and Traditional Tibetan Medicine are well suited to a study aimed at discovering information about medicinal plants to treat Parkinson's disease (PD). In addition, this study across Nepal's altitudinal range is relevant to understanding how cultural and ecological environments influence local traditional medicines. The aim of the study is to document the uses of medicinal plants in three different eco-geographical areas of Nepal (Chitwan-Panchase-Mustang) to treat symptoms related to PD. A second goal is to analyze the impact of culture and environment on the evolution of traditional medicine.

MATERIALS AND METHODS

The study was conducted in five communities located in three different eco-geographical environments and at altitudes ranging from 300m to 3700m. We interviewed a total of 56 participants (local people, folk, Ayurvedic and Amchi healers) across the three research areas. We conducted open-ended interviews to document the uses of medicinal plants to treat PD-related symptoms. Information provided by the interviewees suggested that the medicinal plants are also used to treat symptoms related to other disorders. We determined the informant consensus factor as well as the importance of specific plant species to (i) identify plants that are the best candidates to be analyzed experimentally for their potential to treat PD and (ii) perform a cross-cultural comparison of the three areas of study.

RESULTS

This study reports the local uses of 35 different plant species along the Chitwan-Panchase-Mustang altitudinal range. We identify a total of eight plant species that were used in all three research areas, and more specifically one species used to treat PD-like symptoms. We identify a potential dual protective activity of medicinal plants used to treat PD-related symptoms as recent literature suggests that these plants also have anti-cancer properties. In addition, we document that the presence of Ayurvedic healers could influence local practices and that local practices could influence local Ayurvedic practices.

CONCLUSIONS

This study documents the uses of medicinal plants to treat symptoms related to PD and other disorders across the Chitwan-Panchase-Mustang altitudinal range. PD is a neurodegenerative disease affecting a growing number of people worldwide. No cures are available to slow the death of the neurons, and there is a critical need to work towards innovative therapeutic strategies. We identify medicinal plants based on traditional practices to help develop a cure for PD. The three areas of study were chosen for their ecological and cultural diversities, and two of these are included in conservation programs (Panchase Protected Forest and Annapurna Conservation Area). The documentation of community-natural resource relationships is another step in the preservation of traditional practices and local biodiversity and a reflection of communities' rights in the design of conservation programs.

Antidiabetic and antihyperlipidemic activity of asiatic acid in diabetic rats, role of HMG CoA: in vivo and in silico approaches

Hyperlipidemia is an associated complication of diabetes and also a major risk factor for cardiovascular diseases. The present study was designed to examine the antihyperlipidemic effect of asiatic acid (AA) in streptozotocin (STZ) induced diabetic rats. Diabetes was induced in male Wistar rats by a single intraperitoneal injection of STZ (40 mg/kg b.w.). Diabetic rats show increased plasma glucose, total cholesterol, triglycerides, free fatty acids, phospholipids, low density lipoprotein, very low density liprotein, atherogenic index and decreased insulin and high density lipoprotein in diabetic rats. The activity of 3-hydroxy 3-methylglutaryl coenzyme A (HMG CoA) reductase increased significantly in contrast to the activities of lipoprotein lipase and lecithin cholesterol acyltransferase. In addition, the molecular docking of AA against HMG CoA reductase involved in cholesterol biosynthesis using Argus software. Diabetic rats were treated with AA shifted all these parameters towards normalcy. AA has shown best ligand binding energy 11.8122 kcal/mol. The antihyperlipidemic effect of AA was compared with glibenclamide; a well-known antihyperglycemic drug. In conclusion, this study indicates that AA showed an antihyperlipidemic effect in addition to its antidiabetic effect in experimental diabetes.

Asiatic acid alleviates hemodynamic and metabolic alterations via restoring eNOS/iNOS expression, oxidative stress, and inflammation in diet-induced metabolic syndrome rats

Asiatic acid is a triterpenoid isolated from Centella asiatica. The present study aimed to investigate whether asiatic acid could lessen the metabolic, cardiovascular complications in rats with metabolic syndrome (MS) induced by a high-carbohydrate, high-fat (HCHF) diet. Male Sprague-Dawley rats were fed with HCHF diet with 15% fructose in drinking water for 12 weeks to induce MS. MS rats were treated with asiatic acid (10 or 20 mg/kg/day) or vehicle for a further three weeks. MS rats had an impairment of oral glucose tolerance, increases in fasting blood glucose, serum insulin, total cholesterol, triglycerides, mean arterial blood pressure, heart rate, and hindlimb vascular resistance; these were related to the augmentation of vascular superoxide anion production, plasma malondialdehyde and tumor necrosis factor-alpha (TNF-α) levels (p<0.05). Plasma nitrate and nitrite (NOx) were markedly high with upregulation of inducible nitric oxide synthase (iNOS) expression, but dowregulation of endothelial nitric oxide synthase (eNOS) expression (p<0.05). Asiatic acid significantly improved insulin sensitivity, lipid profiles, hemodynamic parameters, oxidative stress markers, plasma TNF-α, NOx, and recovered abnormality of eNOS/iNOS expressions in MS rats (p<0.05). In conclusion, asiatic acid improved metabolic, hemodynamic abnormalities in MS rats that could be associated with its antioxidant, anti-inflammatory effects and recovering regulation of eNOS/iNOS expression.

Analgesic and anti-inflammatory bioactivities of eburicoic acid and dehydroeburicoic acid isolated from Antrodia camphorata on the inflammatory mediator expression in mice

Eburicoic acid (TR1) and dehydroeburicoic acid (TR2), an active ingredient from Antrodia camphorata (AC) solid-state culture, were evaluated for analgesic and anti-inflammatory effects. Treatment with TR1 and TR2 significantly inhibited a number of acetic acid-induced writhing responses and formalin-induced pain in the late phase. In the anti-inflammatory test, TR1 and TR2 decreased paw edema at the fourth and fifth hour after λ-carrageenan (Carr) administration and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw edema tissue. We also demonstrated that TR1 and TR2 significantly attenuated the malondialdehyde (MDA), nitric oxide (NO), tumor necrosis factor (TNF-α), and interleukin-1β (IL-1β) levels in either edema paw or serum at the fifth hour after Carr injection. Western blotting revealed that TR1 and TR2 decreased Carr-induced inducible nitric oxide synthase (iNOS) and cycloxyclase (COX-2) expressions at the fifth hour in paw edema. Treatment with TR1 and TR2 also diminished neutrophil infiltration into the paw edema at the fifth hour. The present study suggests that the anti-inflammatory mechanisms of TR1 and TR2 might be related to the decrease of inflammatory cytokines and an increase of antioxidant enzyme activity.

Antioxidant, Antinociceptive, and Anti-Inflammatory Activities from Actinidia callosa var. callosa In Vitro and In Vivo

Actinidia callosa var. callosa has been widely used to treat antipyretic, analgesic, anti-inflammation, abdominal pain, and fever in Taiwan. The aim of this study was to evaluate the antioxidant, antinociceptive, and anti-inflammatory lipopolysaccharide-(LPS-)induced nitric oxide (NO) production in RAW264.7 macrophages and pawedema induced by λ-carrageenan activities of the methanol extract from A. callosa. In HPLC analysis, the fingerprint chromatogram of ethyl-acetate fraction of A. callosa (EAAC) was established. EAAC showed the highest TEAC and DPPH radical scavenging activities, respectively. We evaluated that EAAC and the reference compound of catechin and caffeic acid decreased the LPS-induced NO production in RAW264.7 cells. Treatment of male ICR mice with EAAC significantly inhibited the numbers of acetic acid-induced writhing response and the formalin-induced pain in the late phase. Administration of EAAC showed a concentration-dependent inhibition on paw edema development after Carr treatment in mice. Anti-inflammatory mechanisms of EAAC might be correlated to the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and heme oxygenase-1 (HO-1) in vitro and in vivo. Overall, the results showed that EAAC demonstrated antioxidant, antinociceptive, and anti-inflammatory activity, which supports previous claims of the traditional use for inflammation and pain.

Ameliorative Effects of Scopoletin from Crossostephium chinensis against Inflammation Pain and Its Mechanisms in Mice

Scopoletin exists in nature as an anti-oxidant, hepatoprotective, and anti-inflammatory activities reagent. In this study, we have investigated the analgesic effects of the scopoletin using the models of acetic acid-induced writhing response and the formalin test, the anti-inflammatory effects of scopoletin using model of λ-carrageenan (Carr)-induced paw edema. The treatment of ICR mice with scopoletin inhibited the numbers of writhing response and the formalin-induced pain in the late phase. This study demonstrated that the administration of scopoletin resulted in the reduction of Carr-induced mice edema, and it increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) after Carr injection. We also demonstrated scopoletin significantly attenuated the malondialdehyde (MDA) level in the edema paw after Carr injection. Scopoletin decreased the NO, tumor necrosis factor (TNF-α) and prostaglandin E2 (PGE(2)) levels on serum after Carr injection. Scopoletin decreased Carr-induced inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in the edema paw. These anti-inflammatory mechanisms of scopoletin might be related to the decrease in the level of MDA via increasing the activities of SOD, CAT, and GPx in the edema paw. Also, scopoletin could affect the production of NO, TNF-α, and PGE(2), and therefore affect the anti-inflammatory effects.

Involvement of Heme Oxygenase-1 Participates in Anti-Inflammatory and Analgesic Effects of Aqueous Extract of Hibiscus taiwanensis

Anti-inflammatory effects of the aqueous extract of Hibiscus taiwanensis (AHT) were used in lipopolysaccharide (LPS-)stimulated mouse macrophage RAW264.7 cells and carrageenan (Carr-)induced mouse paw edema model. When RAW264.7 macrophages were treated with AHT together with LPS, a concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE(2)) levels productions were detected. Western blotting revealed that AHT blocked protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and elevated heme oxygenase-1 (HO-1), significantly. In the animal test, AHT decreased the paw edema at the 4th and the 5th h after Carr administration, and it increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated AHT decreased the NO, TNF-α, and PGE2 levels on the serum level at the 5th h after the Carr injection. Western blotting revealed that AHT decreased Carr-induced iNOS, and COX-2, and increased HO-1 expressions at the 5th h in the edema paw. These findings demonstrated that AHT has excellent anti-inflammatory activities in vitro and in vivo and thus it has great potential to be used as a source for natural health products.

Anti-inflammatory activities of inotilone from Phellinus linteus through the inhibition of MMP-9, NF-κB, and MAPK activation in vitro and in vivo

Inotilone was isolated from Phellinus linteus. The anti-inflammatory effects of inotilone were studied by using lipopolysaccharide (LPS)-stimulated mouse macrophage RAW264.7 cells and λ-carrageenan (Carr)-induced hind mouse paw edema model. Inotilone was tested for its ability to reduce nitric oxide (NO) production, and the inducible nitric oxide synthase (iNOS) expression. Inotilone was tested in the inhibitor of mitogen-activated protein kinase (MAPK) [extracellular signal-regulated protein kinase (ERK), c-Jun NH₂-terminal kinase (JNK), p38], and nuclear factor-κB (NF-κB), matrix-metalloproteinase (MMP)-9 protein expressions in LPS-stimulated RAW264.7 cells. When RAW264.7 macrophages were treated with inotilone together with LPS, a significant concentration-dependent inhibition of NO production was detected. Western blotting revealed that inotilone blocked the protein expression of iNOS, NF-κB, and MMP-9 in LPS-stimulated RAW264.7 macrophages, significantly. Inotilone also inhibited LPS-induced ERK, JNK, and p38 phosphorylation. In in vivo tests, inotilone decreased the paw edema at the 4^th and the 5^th h after Carr administration, and it increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx). We also demonstrated that inotilone significantly attenuated the malondialdehyde (MDA) level in the edema paw at the 5^th h after Carr injection. Inotilone decreased the NO and tumor necrosis factor (TNF-α) levels on serum at the 5^th h after Carr injection. Western blotting revealed that inotilone decreased Carr-induced iNOS, cyclooxygenase-2 (COX-2), NF-κB, and MMP-9 expressions at the 5^th h in the edema paw. An intraperitoneal (i.p.) injection treatment with inotilone diminished neutrophil infiltration into sites of inflammation, as did indomethacin (Indo). The anti-inflammatory activities of inotilone might be related to decrease the levels of MDA, iNOS, COX-2, NF-κB, and MMP-9 and increase the activities of CAT, SOD, and GPx in the paw edema through the suppression of TNF-α and NO. This study presents the potential utilization of inotilone, as a lead for the development of anti-inflammatory drugs.

Anti-Inflammatory Activities of Cinnamomum cassia Constituents In Vitro and In Vivo

We have investigated the anti-inflammatory effects of Cinnamomum cassia constituents (cinnamic aldehyde, cinnamic alcohol, cinnamic acid, and coumarin) using lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) and carrageenan (Carr)-induced mouse paw edema model. When RAW264.7 macrophages were treated with cinnamic aldehyde together with LPS, a significant concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE(2)) levels productions were detected. Western blotting revealed that cinnamic aldehyde blocked protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear transcription factor kappa B (NF-κB), and IκBα, significantly. In the anti-inflammatory test, cinnamic aldehyde decreased the paw edema after Carr administration, and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated cinnamic aldehyde attenuated the malondialdehyde (MDA) level and myeloperoxidase (MPO) activity in the edema paw after Carr injection. Cinnamic aldehyde decreased the NO, TNF-α, and PGE(2) levels on the serum level after Carr injection. Western blotting revealed that cinnamic aldehyde decreased Carr-induced iNOS, COX-2, and NF-κB expressions in the edema paw. These findings demonstrated that cinnamic aldehyde has excellent anti-inflammatory activities and thus has great potential to be used as a source for natural health products.

Antioxidant, analgesic, and anti-inflammatory activities of the ethanolic extracts of Taxillus liquidambaricola

ETHNOPHARMACOLOGICAL RELEVANCE

[corrected] The Taxillus liquidambaricola has been used to treat rheumatic arthralgia, threatened abortion and hypertension in the Chinese traditional medicine. However, there is no scientific evidence which supports the use in the literature. This study aimed to determine the antioxidant, and analgesic activities and the mechanism of anti-inflammatory activities of the ethanolic extracts of Taxillus liquidambaricola (ETL) in cell and animal models.

MATERIALS AND METHODS

The following activities were investigated: free radical scavenging and antioxidant activities [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and DPPH (1, 1-diphenyl-2-picrylhydrazyl)], analgesic (writhing and formalin test), and anti-inflammatory [lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW264.7 macrophages and paw-edema induced by λ-carrageenan (Carr)]. We also investigate the anti-inflammatory mechanism of ETL via studies of the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) and the levels of malondialdehyde (MDA) in the edema paw. Serum NO and tumor necrosis factor α (TNF-α) were also measured in vivo.

RESULTS

ETL showed the highest TEAC and DPPH radical scavenging activities, respectively. ETL also had highest contents of polyphenol and flavonoid contents. We evaluated that ETL and the reference compound of quercetin decreased the LPS-induced NO production and expressions of iNOS and COX-2 in RAW264.7 cells. Treatment of male ICR mice with ETL significantly inhibited the numbers of acetic acid-induced writhing response and the formalin-induced pain in the late phase. Administration of ETL showed a concentration dependent inhibition on paw edema development after Carr treatment in mice. The anti-inflammatory effects of ETL could be via NO and TNF-α suppression and associated with the increase in the activities of antioxidant enzymes. Western blotting revealed that ETL decreased Carr-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions.

CONCLUSIONS

Anti-inflammatory mechanisms of ETL might be correlated to the decrease in the level of MDA, iNOS, and COX-2 via increasing the activities of CAT, SOD, and GPx in the edema paw. Overall, the results showed that ETL demonstrated antioxidant, antinociceptive, and anti-inflammatory activity, which supports previous claims of the traditional use for inflammation and pain.