Inhibition of nitric oxide synthesis in mouse macrophage cells by feverfew supercritical extract

Feverfew is the most commonly used medicinal herb against migraine headache. The antimigraine mechanism of feverfew supercritical extract was investigated in vitro using the mouse macrophage cell line (RAW 264.7). Mouse macrophage cells were treated with lipopolysaccharide in the presence and absence of feverfew extracts. Inhibition of lipopolysaccharide-induced nitric oxide and TNF-α synthesis were quantified by ELISA. The mRNA and protein expression of iNOS and eNOS genes were analysed by RT-PCR and western blot analysis, respectively. The feverfew extract inhibited both nitric oxide (NO) and TNF-α production in a dose-dependent manner with complete inhibition of NO occurring at 5 μg/mL of feverfew extract. Both eNOS and iNOS mRNA levels were unchanged with the feverfew treatment. However, eNOS and iNOS proteins were significantly down-regulated by the feverfew extract. Feverfew inhibition of NO is due to the down-regulation of both eNOS and iNOS enzymes at the translational and/or post-translational level.     

Antiinflammatory activity of methanol extract isolated from stem bark of Magnolia kobus

The present study reports the antiinflammatory activity of a methanol extract isolated from the stem bark of Magnolia kobus (MK). MK potently inhibited lipopolysaccharide (LPS)-induced production of nitric oxide and interleukin-1beta (IL-1beta) in RAW 264.7 cells, a murine macrophage-like cell line. The secretion of tumor necrosis factor-alpha (TNF-alpha) was also suppressed in LPS-stimulated RAW 264.7 cells although the magnitude of inhibition was weaker than that of nitric oxide and IL-1beta. The mRNA expressions of inducible nitric oxide synthase (iNOS), IL-1beta and TNF-alpha were also suppressed by MK in LPS-stimulated RAW 264.7 cells. Further study demonstrated that LPS-induced DNA binding of AP-1 and phosphorylation of c-jun N-terminal kinase (JNK) were inhibited by MK treatment in RAW 264.7 cells, whereas phosphorylation of p38 mitogen-activated protein kinase was unaffected. Moreover, topical application of MK suppressed ear swelling in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation model. Collectively, these results suggest that MK exerts antiinflammatory effects in vitro and in vivo and this might be mediated, at least in part, by blocking AP-1 and JNK activation.     

Effects of armepavine against hepatic fibrosis induced by thioacetamide in rats

The aim of this study was to investigate if armepavine (Arm, C₁₉H₂₃O₃N) could exert inhibitory effects against hepatic fibrosis in rats. A cell line of rat hepatic stellate cells (HSC‐T6) was stimulated with tumour necrosis factor‐α (TNF‐α) to evaluate the inhibitory effects of Arm. Rats were injected with thioacetamide (TAA; 300 mg/kg, intraperitoneally) thrice a week for 4 weeks to induce hepatic fibrosis, with Arm (3 or 10 mg/kg) given by gavage twice a day. Liver sections were taken for western blotting, fibrosis scoring and immunofluorescence staining. Arm (1–10 µm ) concentration‐dependently attenuated TNF‐α‐stimulated: (i) protein expressions of α‐smooth muscle actin (α‐SMA), collagen type I and angiopoietin‐1; (ii) H₂O₂ production; and (iii) NF‐κB, JunD and C/EBPß (cytidine‐cytidine‐adenosine‐adenosine‐thymidine (CCAAT)/enhancer binding protein‐ß (EBPß)) nuclear translocations in HSC‐T6 cells. In vivo Arm treatment significantly reduced plasma aspartate transaminase and alanine transaminase levels, hepatic α‐SMA expression and collagen contents, and fibrosis scores of TAA‐injected rats. Moreover, Arm treatment decreased α‐SMA‐ and NF‐κB‐positive cells in immunohistochemical staining, and mRNA expression levels of IL‐6, TGF‐ß1, TIMP‐1, col1α2, iNOS and ICAM‐1 genes, but up‐regulated the metallothionein gene in the livers of TAA‐injected rats. Our results indicated that Arm exerted both in vitro and in vivo antifibrotic effects in rats, with inhibition of NF‐κB, JunD and C/EBPß pathways. Copyright © 2011 John Wiley & Sons, Ltd.     

Protective effects of sugar cane extract on endotoxic shock in mice

Sugar cane extract (SCE) has been shown to have an immunostimulating effect in chickens. This study evaluated the effect of SCE on Salmonella Abortusequi lipopolysaccharide (LPS)-induced lethal shock in d-galactosamine (GalN)-sensitized mice. Mice were administered intraperitoneally SCE (500 mg/kg) or phosphate buffered saline before or after injection of LPS and GalN. All the mice injected with LPS and GalN (control group) died of histopathologically congestive and hemorrhagic hepatic insufficiency within 24 h, showing significantly increased activities of plasma aspartate aminotransferase (AST; 380 IU/mL) and alanine aminotransferase (ALT; 130 IU/mL). Pretreatment of mice with SCE at 3 h before challenge with LPS and GalN (SCE treated group) resulted in significantly improved survival rates (92.3%) and a decrease in liver injury. These surviving mice in the SCE treated group showed no changes in the mean levels of plasma AST (60 IU/mL) and ALT (18 IU/mL). However, the level of tumor necrosis factor-alpha in the SCE treated group was not significantly different when compared with that in the control group challenged with LPS and GalN. These results suggest that SCE has protective effects on LPS-induced mortality in this mouse model.     

Inhibition of tumour necrosis factor-alpha secretion from rat astrocytes by Sesim-Tang.

Substance P (SP) can stimulate secretion of tumour necrosis factor-alpha (TNF-alpha) from astrocytes stimulated with lipopolysaccharide (LPS). In this study, we have examined whether an aqueous extract of Sesim-Tang inhibits the secretion of TNF-alpha from primary cultures of rat astrocytes. Sesim-Tang (10-1000 microg/mL) significantly inhibited the TNF-alpha secretion by astrocytes stimulated with LPS and SP. Interleukin-1 (IL-1) has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore examined whether IL-1 mediated inhibition of TNF-alpha secretion from primary astrocytes by Sesim-Tang. Treatment with Sesim-Tang (10-1000 microg/mL) of astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. Moreover, the secretion of TNF-alpha by LPS and SP in astrocytes was progressively inhibited with increasing amounts of IL-1 neutralizing antibody. Our results suggest that Sesim-Tang may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that Sesim-Tang has an antiinflammatory activity in the central nervous system.     

Protective effect of daidzin against d‐galactosamine and lipopolysaccharide‐induced hepatic failure in mice

This study examined the effects of daidzin, a major isoflavone from Puerariae Radix, on d ‐galactosamine (d ‐GalN) and lipopolysaccharide (LPS)‐induced liver failure. Mice were given an intraperitoneal injection of daidzin (25, 50, 100 and 200 mg/kg) 1 h before receiving an injection of d ‐GalN (700 mg/kg)/LPS (10 µg/kg). Daidzin markedly reduced the elevated serum aminotransferase activity and the levels of lipid peroxidation and tumor necrosis factor‐α. The glutathione content was lower in the d ‐GalN/LPS group, which was attenuated by daidzin. The daidzin pretreatment attenuated the swollen mitochondria observed in the d ‐GalN/LPS group. Daidzin attenuated the apoptosis of hepatocytes, which was confirmed using the terminal deoxynucleotidyl transferase‐mediated dUTP nick end‐labeling method and a caspase‐3 assay. Overall, these results suggest that the liver protection of daidzin is due to reduced oxidative stress and its antiapoptotic activity. Copyright © 2008 John Wiley & Sons, Ltd.     

Effects of soybean ethanol extract on the cell survival and oxidative stress in osteoblastic cells

Recent evidence suggests that high concentrations of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) are thought to increase the apoptosis in osteoblasts and bone resorption and may have important roles in the regulation of osteoblast and osteoclast metabolism, especially in rheumatoid arthritis. The present study was performed to investigate the effect of soybean ethanol extract on the scavenging properties using DPPH and the TNF-alpha and NO production of osteoblastic MC3T3-E1 cells. The soy extract and its fractions according to polarity displayed a strong free radical scavenger activity at 0.01 approximately 0.1g/L, except for aquous fraction which had no significant effect on the function of MC3T3-E1 cells (p < 0.05). TNF-alpha secretion by MC3T3-E1 cells was reduced significantly when stimulated with soy extract (0.05 g/L). Nitrite accumulation in culture medium and apoptosis of MC3T3-E1 cells were induced by the addition of 10(-10) M TNF-alpha, and inhibited by the simultaneous addition of soy extract (0.05g/L).     

Emblica officinalis corrects functional, biochemical and molecular deficits in experimental diabetic neuropathy by targeting the oxido-nitrosative stress mediated inflammatory cascade

Diabetic neuropathy is one of the most common microvascular complications of diabetes mellitus which affects more than 50% of diabetic patients. Diabetic neuropathic pain is amongst the most difficult types of pain to treat mainly due to the lack of understanding of its etiology and inadequate relief with available drug therapy. The present study targeted oxidative stress mediated nerve damage in diabetic rats using an aqueous extract of Emblica officinalis, a potent natural antioxidant. Diabetic rats exhibited significantly decreased tail‐flick latency in the tail‐immersion test (thermal hyperalgesia) and decreased paw withdrawal threshold in both Randall‐Selitto (mechanical hyperalgesia) and von‐Frey hair test (mechanical allodynia). A decrease in the nociceptive threshold was accompanied by significantly increased oxidative stress, nitrite levels and cytokines (TNF‐α, IL‐1β and TGF‐β1) both in the serum and sciatic nerve of diabetic rats. Treatment with the Emblica officinalis aqueous extract (250, 500 and 1000 mg/kg/day) significantly attenuated all the behavioral, biochemical and molecular alterations in a dose‐dependent manner. The major finding of the study is that insulin alone corrected the hyperglycemia and partially reversed the pain response in diabetic rats. However, combination with Emblica officinalis extract not only attenuated the diabetic condition but also reversed neuropathic pain through modulation of oxidative–nitrosative stress in diabetic rats. Copyright © 2011 John Wiley & Sons, Ltd.     

Praeruptorin a inhibits lipopolysaccharide‐induced inflammatory response in murine macrophages through inhibition of NF‐κB pathway activation

Praeruptorin A (PA) is a pyranocoumarin compound isolated from the dried root of Peucedanum praeruptorum Dunn (Umbelliferae). However, the antiinflammatory effect of PA has not been reported. The present study investigated the antiinflammatory effect of PA in lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophage cells. PA significantly inhibited the LPS‐induced production of nitric oxide (NO), interleukin‐1β (IL‐1β) and tumor necrosis factor‐α (TNF‐α). The mRNA and protein expressions of inducible nitric oxide synthase (iNOS), IL‐1β and TNF‐α were also suppressed by this compound. Further study showed that PA decreased the cytoplasmic loss of inhibitor κB‐α (IκB‐α) protein and inhibited the translocation of NF‐κB from cytoplasm to nucleus. Taken together, the results suggest that PA may exert antiinflammatory effects in vitro in LPS‐stimulated RAW 264.7 macrophages through inhibition of NF‐κB signal pathway activation. Copyright © 2010 John Wiley & Sons, Ltd.     

Wen-pi-tang-Hab-Wu-ling-san attenuates kidney fibrosis induced by ischemia/reperfusion in mice

Renal fibrosis is highly implicated as a cause of chronic renal failure, for which suitable therapeutics have not yet been developed. Recently, it was reported that Wen-pi-tang-Hab-Wu-ling-san (WHW) extract attenuates epithelial cells undergoing mesenchymal transition in cultured Madin-Darby canine kidney cells. This study investigated whether WHW extract prevents renal fibrosis induced by ischemia/reperfusion (I/R) in mice. Ischemia/reperfusion resulted in kidney fibrosis at 14 days after the procedure. When WHW was administered orally to mice beginning from 2 days after the onset of ischemia until killing, the fibrosis was significantly reduced. WHW administration significantly prevented a post-ischemic decrease of copper-zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD) activities, leading to decreased lipid peroxidation and hydrogen peroxide production. In addition, WHW administration attenuated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase 1/2 (JNK1/2) and attenuated the activation of nuclear factor-kappa B (NF-kappaB) in the kidneys subjected to ischemia. In conclusion, WHW extract attenuated the renal fibrosis and the attenuation was associated with a reduction of oxidative stress and an inhibition of ERK1/2, JNK1/2, p38 and NF-kappaB activation. WHW extract may be an attractive agent to attenuate the progression of fibrosis.     

SunghyangJungki-San Ga Pogongyoung inhibits IL-1 mediated tumour necrosis factor-alpha secretion in astrocytes

Astrocytes play an important role in initiating and modulating inflammatory responses within the central nervous system (CNS). Extensive studies in rodents have shown that substance P induces inflammatory cytokine production in astrocytes. In this study we have examined whether an aqueous extract of SunghyangJungki-San Ga Pogongyoung (SSGP) inhibits the secretion of TNF-alpha from primary cultures of rat astrocytes. SSGP (10-1,000 microg/mL) significantly inhibited the TNF-alpha secretion by astrocytes stimulated with lipopolysaccharide (LPS) and substance P (SP). Interleukin-1 (IL-1) has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore examined whether IL-1 mediated inhibition of TNF-alpha secretion from primary astrocytes by SSGP. Treatment with SSGP (10-1,000 microg/mL) to astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. Moreover, the secretion of TNF-alpha by LPS and SP in astrocytes was progressively inhibited with an increasing amount of IL-1 neutralizing antibody. Our results suggest that SSGP may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that SSGP has an antiinflammatory activity in the CNS.     

Effect of Seabuckthorn (Hippophae rhamnoides) flavone on immune system: an in-vitro approach

There are several reports, which suggest that the consumption of foods rich in flavonoids is associated with a lower incidence of certain degenerative diseases, including cardiovascular disease. Flavones, of Seabuckthorn (SBT) (Hippophae rhamnoides L.) fruit berry can modulate the production and level of several signaling molecules associated with immune function and inflammation in vitro, including several cytokines. We have evaluated the immunomodulatory activity of ethanolic solution of SBT flavone (FLV) in human peripheral blood mononuclear cells (PBMCs). The SBT flavone was found to stimulate production of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in PBMCs. However, increased expressions of p-IkappaB, NF-kappaB, and p-p38 were found in flavone-treated human PBMCs with significantly suppressed expression of CD25 (IL-2R). There was no alteration found in the nitric oxide (NO) production in mouse macrophage cell line RAW 264.7. These observations suggest that stimulation of IL-6 and TNF-alpha secretion may contribute to the putative beneficial effects of dietary flavone against microbial infection.     

Action of Rubus coreanus extract on systemic and local anaphylaxis

The effect was investigated of the aqueous extract of Rubus coreanus Miq. (Rosaceae) fruits (RCAE) on systemic and local anaphylaxis. RCAE (0.01-1 g/kg) dose-dependently inhibited systemic anaphylaxis induced by compound 48/80 in mice. RCAE (1 g/kg) also significantly inhibited local anaphylaxis activated by anti-DNP IgE. Pretreatment with RCAE at the same concentration before systemic anaphylaxis reduced the plasma histamine levels in a dose-dependent manner. RCAE (0.001-1 mg/mL) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cAMP in RPMC, when RCAE was added, significantly increased, compared with that of the normal control. Moreover, RCAE (0.01-1 mg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumour necrosis factor-alpha production from RPMC. These results indicate that RCAE may possess antianaphylactic action.     

Astragaloside IV attenuates lipolysis and improves insulin resistance induced by TNFalpha in 3T3-L1 adipocytes

Increased circulating free fatty acid (FFA) concentrations have been demonstrated to potentially link obesity, insulin resistance and cardiovascular diseases. Astragaloside IV (AS-IV) is a saponin which is widely used in traditional Chinese medicine to treat type 2 diabetes and cardiovascular diseases. The purpose of the present study was to examine the effects of AS-IV on the lipolysis and insulin resistance induced by tumor necrosis factor-alpha (TNFalpha) in cultured 3T3-L1 adipocytes. TNFalpha promotes lipolysis in mammal adipocytes via the mitogen activated protein kinase (MAPK) family resulting in reduced expression/function of perilipin. Application of AS-IV inhibited TNFalpha-induced accelerated lipolysis in a dose-dependent manner, which was compatible with suppressed phosphorylation of ERK1/2 and reversed the downregulation of perilipin. Moreover, TNFalpha induced downregulation of key enzymes in lipogenesis, including LPL, FAS and GPAT, were also attenuated by AS-IV. Further studies showed that AS-IV improved TNFalpha-induced insulin resistance in 3T3-L1 adipocytes. This study provides the first direct evidence of the antilipolytic action of AS-IV in adipocytes, which may allow this agent to decrease the circulating FFA levels, thus increase insulin sensitivity and treat cardiovascular diseases.     

Attenuation of colitis injury in rats using Garcinia cambogia extract

Inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis are chronic enteropathies that probably result from a dysregulated mucosal immune response. These pathologies are characterized by oxidative and nitrosative stress, leukocyte infiltration and up-regulation of pro-inflammatory substances. Current IBD treatment presents limitations in both efficacy and safety that stimulated the search for new active compounds. Garcinia cambogia extract has attracted interest due to its pharmacological properties, including gastroprotective effects. In this study, the antiinflammatory activity of a garcinia extract was assessed in TNBS-induced colitis rats. The results obtained revealed that garcinia administration to colitic rats significantly improved the macroscopic damage and caused substantial reductions in increases in MPO activity, COX-2 and iNOS expression. In addition, garcinia extract treatment was able to reduce PGE(2) and IL-1beta colonic levels. These antiinflammatory actions could be related to a reduction in DNA damage in isolated colonocytes, observed with the comet assay. Finally, garcinia extract caused neither mortality nor toxicity signals after oral administration. As such, the antiinflammatory effects provided by the Garcinia cambogia extract result in an improvement of several parameters analysed in experimental colitis and could provide a source for the search for new antiinflammatory compounds useful in IBD treatment.     

Neuroprotective Effect of Vitamin E Isoforms Against Chronic Alcohol‐induced Peripheral Neurotoxicity: Possible Involvement of Oxidative‐Nitrodative Stress

Small‐fiber painful peripheral neuropathy is one of the long‐term complications of alcohol for which there is no reliable successful therapy available. The precise mechanisms by which chronic alcohol consumption produces peripheral nerve fiber damage and loss remain unclear. Emerging data from clinical and preclinical studies suggest that increased oxidative‐nitrodative stress mediated release of proinflammatory cytokines from damaged neural tissues may play a central role in the pathogenesis of alcoholic neuropathy. The present study investigated the effect of both the isoforms of vitamin E (α‐tocopherol and tocotrienol) against chronic alcohol‐induced peripheral neuropathy in rats. Ethanol treated rats showed a significant decrease in paw‐withdrawal threshold in both Randall‐Selitto and von‐Frey hair tests along with a significant reduction in tail flick latency in the tail‐immersion test. A decreased pain threshold was associated with significant alterations in oxidative‐nitrodative stress markers and an increase in proinflammatory cytokines (TNF‐α and IL‐1β). The 4‐week treatment with tocotrienol significantly ameliorated behavioral, biochemical and molecular alterations in alcohol treated rats. However, α‐tocopherol failed to produce any protective effect. The results of the present study suggest that oxidative‐nitrodative stress mediated cytokine signaling may be responsible for alcohol‐induced peripheral neurotoxicity and tocotrienol treatment might be beneficial in chronic alcoholics exhibiting neuropathy. Copyright © 2012 John Wiley & Sons, Ltd.