Transmembrane TNF drives osteoproliferative joint inflammation reminiscent of human spondyloarthritis.

TNF plays a key role in immune-mediated inflammatory diseases including rheumatoid arthritis (RA) and spondyloarthritis (SpA). It remains incompletely understood how TNF can lead to different disease phenotypes such as destructive peripheral polysynovitis in RA versus axial and peripheral osteoproliferative inflammation in SpA. We observed a marked increase of transmembrane (tm) versus soluble (s) TNF in SpA versus RA together with a decrease in the enzymatic activity of ADAM17. In contrast with the destructive polysynovitis observed in classical TNF overexpression models, mice overexpressing tmTNF developed axial and peripheral joint disease with synovitis, enthesitis, and osteitis. Histological and radiological assessment evidenced marked endochondral new bone formation leading to joint ankylosis over time. SpA-like inflammation, but not osteoproliferation, was dependent on TNF-receptor I and mediated by stromal tmTNF overexpression. Collectively, these data indicate that TNF can drive distinct inflammatory pathologies. We propose that tmTNF is responsible for the key pathological features of SpA.

[FAS- and TNF-dependent ways participation in apoptosis mechanisms in hypotalumus in physiological and pathological aging.]

The cell resistance to apoptosis can be related to the activity of cytokine-dependent signaling. So, the aim of the work is to investigate the mechanisms of cytokine-dependent FAS/TNF-mediated regulation of apoptosis of neurosecretory cells in the physiological and pathological (overexpression of the oncogene HER-2/Neu) aging. HER2/Neu transgenic accelerated aged mice of different ages and wild type FVB/N were examined. The apoptosis level of neurons in hypothalamic sections (supraoptic and paraventricular nuclei) (TUNEL) and expression of caspase-8, CD178 (FASL), FAS, FADD, TRADD (Western blotting) was determined. Participation of the proinflammatory component in the aging process is shown. FAS, adapter proteins associated with the death domain (FADD and TRADD), caspase-8 expression is activated in hypothalamus in FVB/N mice (wild type) during aging, and it correlates with an increase in the apoptosis level. HER-2/Neu expression leads to the extrinsic apoptotic pathway suppression. In this case, the reception of an apoptotic signal (FAS-receptor expression) and its further transmission (expression of FADD and TRADD) is suppressed. However, in young transgenic mice, increased expression of TRADD can activate one of the survival ways - NF-κB, ERK or PI3K-AKT cascade. Thus, the HER-2/Neu tyrosine kinase receptor plays a role in the mechanism of cell resistance to age-dependent apoptosis, and the FAS/TNF-signaling pathway is one of the targets of HER-2/Neu.

The anti-diabetic activities, gut microbiota composition, the anti-inflammatory effects of Scutellaria-coptis herb couple against insulin resistance-model of diabetes involving the toll-like receptor 4 signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria-coptis herb couple (SC) is one of the well-known herb couples in many traditional Chinese compound formulas used for the treatment of diabetes mellitus (DM), which has been used to treat DM for thousands of years in China. AIM OF THE STUDY: Few studies have confirmed in detail the anti-diabetic activities of SC in vivo and in vitro. The present investigations aimed to evaluate the anti-diabetic activity of SC in type 2 diabetic KK-Ay mice and in RAW264.7 macrophages to understand its possible mechanism. MATERIALS AND METHODS: High-performance liquid chromatography with ultraviolet detection (HPLC-UV) and LC-LTQ-Orbitrap Pro mass spectrometry were used to analyze the active ingredients of SC extracts and control the quality. A type 2 diabetic KK-Ay mice model was established by high-fat diet. Body weight, fasting blood glucose levels, fasting blood insulin levels, glycosylated hemoglobin and glycosylated serum protein were measured. The effects of SC on total cholesterol (TC), high-density lipoprotein (HDL) and triglyceride (TG) levels were examined. The lipopolysaccharide (LPS), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) levels were measured. Gut microbial communities were assayed by polymerase chain reaction (PCR) and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) methods. The expressions of Toll-like receptor 4 (TLR4) and MyD88 protein in the colons were measured by western blot. In RAW264.7 macrophages, IL-6, TNF-α, TLR4 and MyD88 protein levels were measured by enzyme-linked immunosorbent assay (ELISA) kits or western blot, and the mRNA expression of IL-6, TNF-α and TLR4 was examined by the real time PCR. RESULTS: The present results showed that the SC significantly increased blood HDL and significantly reduced fasting blood glucose, fasting blood insulin, glycosylated hemoglobin, glycosylated serum protein, TC, TG, LPS, IL-6 and TNF-α levels (P < 0.05 or P < 0.01) in type-2 diabetic KK-Ay mice. Furthermore, SC could regulate the structure of intestinal flora. Additionally, the expressions of TLR4 and MyD88 protein in the colons were significantly decreased in the model group (P < 0.05 or P < 0.01). However, SC had no significant effect on weight gain. In RAW264.7 macrophages, SC containing serum (SC-CS) (5%, 10% and 20%) significantly decreased IL-6, TNF-α, TLR4 and MyD88 protein levels and the mRNA expression of IL-6, TNF-α and TLR4 (P < 0.05 or P < 0.01). CONCLUSIONS: The anti-diabetic effects of SC were attributed to its regulation of intestinal flora and anti-inflammation involving the TLR4 signaling pathway. These findings provide a new insight into the anti-diabetic application for SC in clinical settings and display the potential of SC in the treatment of DM.

Inhibition of TNFα-induced interleukin-6 gene expression by barley (Hordeum vulgare) ethanol extract in BV-2 microglia.

BACKGROUND: Inflammation in the central nervous system is closely associated with pathological neurodegenerative diseases as well as psychiatric disorders. Prolonged activation of microglia can produce many inflammatory mediators, which may result in pathological neurotoxic side effects. Interleukin (IL)-6 serves as a hallmark of the injured brain. OBJECTIVE: Whole grains are known to contain many bioactive components. However, little information is available about anti-neuroinflammatory effects of grains in the CNS. This study aims to investigate the effect of Hordeum vulgare ethanol extract (HVE) on the suppression of IL-6 expression in BV2 microglia. METHODS: Inhibitory effects of HVE on IL-6 expression were analyzed by immunoblot anaysis, immunofluoresce microscopic analysis, reverse transcription-polymerase chain reaction, and luciferase promoter reporter assay. RESULTS: HVE inhibited TNFα-induced phosphorylation of IKKα/ß, IκB, and p65/RelA NF-κB. TNFα-induced IL-6 mRNA expression and promoter activity were reduced by HVE. Point mutation of NF-κB-binding site within the IL-6 gene promoter abolished TNFα-induced reporter activity, whereas exogenous expression of p65 NF-κB enhanced IL-6 promoter activity. CONCLUSION: NF-κB-binding site within the IL-6 promoter region is a HVE target element involved in the inhibition of TNFα-induced IL-6 gene transcription. HVE inhibits TNFα-induced IL-6 expression via suppression of NF-κB signaling in BV2 microglial cells.

Manual acupuncture relieves bile acid-induced itch in mice: the role of microglia and TNF-α.

Pruritus, or itch, is a frequent complaint amongst patients with cholestatic hepatobiliary disease and is difficult to manage, with many patients refractory to currently available antipruritic treatments. In this study, we examined whether manual acupuncture (MA) at particular acupoints represses deoxycholic acid (DCA)-induced scratching behavior and microglial activation and compared these effects with those induced by another pruritogen, 5'-guanidinonaltrindole (GNTI, a kappa opioid receptor antagonist). MA at Hegu (LI4) and Quchi (LI11) acupoints significantly attenuated DCA- and GNTI-induced scratching, whereas no such effects were observed at the bilateral Zusanli acupoints (ST36). Interestingly, GNTI-induced scratching was reduced similarly by both MA and electroacupuncture (EA) at the LI4 and LI11 acupoints. MA at non-acupoints did not affect scratching behavior. Intraperitoneal injection of minocycline (a microglial inhibitor) reduced GNTI- and DCA-induced scratching behavior. In Western blot analysis, subcutaneous DCA injection to the back of the neck increased spinal cord expression of ionized calcium-binding adapter molecule 1 (Iba1) and tumor necrosis factor-alpha (TNF-α) as compared with saline injection, while MA at LI4 and LI11 reduced these DCA-induced changes. Immunofluorescence confocal microcopy revealed that DCA-induced Iba1-positive cells with thicker processes emanated from the enlarged cell bodies, while this effect was attenuated by pretreatment with MA. It is concluded that microglia and TNF-α play important roles in the itching sensation and MA reduces DCA-induced scratching behavior by alleviating spinal microglial activation. MA may be an effective treatment for cholestatic pruritus.

Role of Curcumin in Regulation of TNF-α Mediated Brain Inflammatory Responses.

BACKGROUND: Inflammation is a protective response of the body system that protects the body from the various kinds of external and internal insults; however, it has been found that most chronic illnesses are caused by dysregulated and excessive inflammation. Inflammation plays a major role in developing neurological diseases. In the brain cytokines, TNF-α and TNF-ß are known to mediate inflammation in many diseases. Functions of these cytokines are regulated by the activation of transcription factor NF-κb. Recent evidence suggest that curcumin has an immense therapeutic potential because of its anti-inflammatory and anti-oxidant properties. It has been tested for treating various chronic illnesses associated with the brain. OBJECTIVE: The study aims to elucidate the role of curcumin in alleviating the inflammatory reactions initiated by TNF-α and NF-κb signaling. METHODS: This study is a survey of literature from sources like PubMed central, science direct, medline and available scientific databases to determine how inflammation plays an important role in the development of neurodegenerative diseases and the role of curcumin as an anti-inflammatory agent. Looking into the importance of curcumin in alleviating inflammatory responses, several patents are filed and accepted which are referenced in this article. RESULTS: Neuro-inflammation mediated by TNF-α plays a major role in the development of pathologies like Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis etc. Curcumin appears to subside or reduce the inflammatory responses. Thus, it appears to have therapeutic potential for treating various neuroinflammatory diseases. CONCLUSION: Cytokines get upregulated during neurodegenerative diseases as a result of which inflammatory responses are initiated in the brain. Curcumin is reported to have anti-inflammatory properties and thereby its supplementation may help in reducing the inflammation. Future research on this area will further explain the mode of action of curcumin in alleviating neuroinflammation.

Anti-inflammatory effects of exercise: role in diabetes and cardiovascular disease.

BACKGROUND: Persistent inflammation is involved in the pathogenesis of chronic diseases such as type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). AIMS: The aim of this review was to provide the reader with an update of the mechanisms whereby exercise-induced cytokines may impact cardiometabolic diseases. RESULTS: Evidence exists that interleukin (IL)-1ß is involved in pancreatic ß-cell damage, whereas TNF-α is a key molecule in peripheral insulin resistance. In addition, TNF-α appears to be involved in the pathogenesis of atherosclerosis and heart failure. A marked increase in IL-6 and IL-10 is provoked by exercise and exerts direct anti-inflammatory effects by an inhibition of TNF-α and by stimulating IL-1ra, thereby limiting IL-1ß signalling. Moreover, muscle-derived IL-6 appears to have direct anti-inflammatory effects and serves as a mechanism to improve glucose tolerance. In addition, indirect anti-inflammatory effects of long-term exercise are mediated via improvements in body composition. CONCLUSION: Physical activity represents a natural, strong anti-inflammatory strategy with minor side effects and should be integrated in the management of patients with cardiometabolic diseases.

Allergen-Removed Rhus verniciflua Extract Induces Ovarian Cancer Cell Death via JNK Activation.

Nuclear factor-[Formula: see text]B (NF-[Formula: see text]B)/Rel transcription factors are best known for their central roles in promoting cell survival in cancer. NF-[Formula: see text]B antagonizes tumor necrosis factor (TNF)-[Formula: see text]-induced apoptosis through a process involving attenuation of the c-Jun-N-terminal kinase (JNK). However, the role of JNK activation in apoptosis induced by negative regulation of NF-[Formula: see text]B is not completely understood. We found that allergen-removed Rhus verniciflua Stokes (aRVS) extract-mediated NF-[Formula: see text]B inhibition induces apoptosis in SKOV-3 ovarian cancer cells via the serial activation of caspases and SKOV-3 cells are most specifically suppressed by aRVS. Here, we show that in addition to activating caspases, aRVS extract negatively modulates the TNF-[Formula: see text]-mediated I[Formula: see text]B/NF-[Formula: see text]B pathway to promote JNK activation, which results in apoptosis. When the cytokine TNF-[Formula: see text] binds to the TNF receptor, I[Formula: see text]B dissociates from NF-[Formula: see text]B. As a result, the active NF-[Formula: see text]B translocates to the nucleus. aRVS extract (0.5[Formula: see text]mg/ml) clearly prevented NF-[Formula: see text]B from mobilizing to the nucleus, resulting in the upregulation of JNK phosphorylation. This subsequently increased Bax activation, leading to marked aRVS-induced apoptosis, whereas the JNK inhibitor SP600125 in aRVS extract treated SKOV-3 cells strongly inhibited Bax. Bax subfamily proteins induced apoptosis through caspase-3. Thus, these results indicate that aRVS extract contains components that inhibit NF-[Formula: see text]B signaling to upregulate JNK activation in ovarian cancer cells and support the potential of aRVS as a therapeutic agent for ovarian cancer.

Chronic Calcium Channel Inhibitor Verapamil Antagonizes TNF-α-Mediated Inflammatory Reaction and Protects Against Inflammatory Arthritis in Mice.

It is well established that the tumor necrosis factor-α (TNF-α) plays a dominant role in rheumatoid arthritis (RA). Calcium channel is recently reported to be closely associated with various inflammatory diseases. However, whether chronic calcium channel blocker verapamil plays a role in RA still remains unknown. To investigate the role of verapamil in antagonizing TNF-α-mediated inflammation reaction and the underlying mechanisms, bone marrow-derived macrophages (BMDM) cells were cultured with stimulation of TNF-α, in the presence or absence of verapamil. Inflammation-associated cytokines, including IL-1, IL-6, inducible nitric oxide synthase 2 (NOS-2), and cyclooxygenase-2 (COX-2), were assessed, and verapamil suppressed TNF-α-induced expression of inflammatory cytokines. Furthermore, collagen-induced arthritis (CIA) mice models were established, and arthritis progression was evaluated by clinical and histological signs of arthritis. Treatment of verapamil attenuated inflammation as well as joint destruction in arthritis models. In addition, activity of NF-kB signaling pathway was determined both in vitro and in mice arthritis models, and verapamil inhibited TNF-α-induced activation of NF-kB signaling both in vitro and in mice models. Collectively, chronic calcium channel blocker verapamil may shed light on treatment of inflammatory arthritis and provide a potential therapeutic instrument for RA in the future.

Central Leptin and Tumor Necrosis Factor-α (TNFα) in Diurnal Control of Blood Pressure and Hypertension.

Leptin and TNFα can individually work in the brain to affect blood pressure; however, it remains unknown whether these two cytokines might have an interactive role in this process and, if so, how. In this work, we found that leptin stimulation led to TNFα production under both in vitro and in vivo conditions, and diurnal fluctuation of leptin concentrations in the cerebrospinal fluid predicted the circadian changes of TNFα gene expression in the hypothalamus. Signaling analysis showed that leptin stimulation led to a rapid and strong STAT3 activation followed by a second-phase moderate STAT3 activation, which was selectively abolished by anti-inflammatory chemical PS1145 or TNFα antagonist WP9QY. Physiological study in normal mice revealed that diurnal rise of blood pressure was abrogated following central administration of PS1145 or a leptin receptor antagonist. Central TNFα pretreatment was found to potentiate the effect of leptin in elevating blood pressure in normal mice. In pathophysiology, dietary obesity mimicked TNFα pretreatment in promoting leptin-induced blood pressure rise, and this effect was blocked by central treatment with either PS1145 or WP9QY. Hence, central leptin employs TNFα to mediate the diurnal blood pressure elevation in physiology while enhancement of this mechanism can contribute to hypertension development.

Attenuation of genotoxicity, oxidative stress, apoptosis and inflammation by rutin in benzo(a)pyrene exposed lungs of mice: plausible role of NF-κB, TNF-α and Bcl-2.

BACKGROUND: Benzo(a)pyrene [B(a)P] is an environmental contaminant and potential carcinogenic agent that causes lung injuries which leads to lung cancer. Rutin, a well-known flavonoid present in various natural sources, possesses biological activities such as anti-oxidative and anti-inflammatory properties. The aim of this study was to evaluate the protective effects of rutin against B(a)P-induced genotoxicity, oxidative stress, apoptosis and inflammation in Swiss albino mice. METHODS: Pretreatment of rutin was given by oral gavage at doses of 40 and 80 mg/kg body weight (b.wt.) for 7 days before the administration of a single oral dose of B(a)P (125 mg/kg b.wt.). The ameliorative effect of rutin on oxidative stress, apoptotic and inflammatory markers in lung tissues and genotoxicity was studied using an alkaline unwinding assay and DNA fragmentation. RESULTS: B(a)P enhanced lipid peroxidation, xanthine oxidase, H2O2 generation and lactate dehydrogenase (LDH) activity; depleted activities of anti-oxidant enzymes and glutathione content; induced DNA strand breaks and fragmentation; disrupted normal histopathological architecture and also showed abnormal expression of NF-κB, COX-2, IL-6, TNF-α and Bcl-2. Rutin pretreatment caused a significant reduction in lipid peroxidation and LDH activity; increased glutathione content; restored antioxidant enzyme activity; reduced DNA strand breaks and fragmentation; modulated the expression of inflammatory, and apoptotic markers and restored the histopathological structure. CONCLUSIONS: The findings of the present study supported the protective effect of rutin against B(a)P-induced lung toxicity and genotoxicity.

Inhibition of Canonical NF-κB Signaling by a Small Molecule Targeting NEMO-Ubiquitin Interaction.

The IκB kinase (IKK) complex acts as the gatekeeper of canonical NF-κB signaling, thereby regulating immunity, inflammation and cancer. It consists of the catalytic subunits IKKα and IKKß and the regulatory subunit NEMO/IKKγ. Here, we show that the ubiquitin binding domain (UBAN) in NEMO is essential for IKK/NF-κB activation in response to TNFα, but not IL-1ß stimulation. By screening a natural compound library we identified an anthraquinone derivative that acts as an inhibitor of NEMO-ubiquitin binding (iNUB). Using biochemical and NMR experiments we demonstrate that iNUB binds to NEMOUBAN and competes for interaction with methionine-1-linked linear ubiquitin chains. iNUB inhibited NF-κB activation upon UBAN-dependent TNFα and TCR/CD28, but not UBAN-independent IL-1ß stimulation. Moreover, iNUB was selectively killing lymphoma cells that are addicted to chronic B-cell receptor triggered IKK/NF-κB activation. Thus, iNUB disrupts the NEMO-ubiquitin protein-protein interaction interface and thereby inhibits physiological and pathological NF-κB signaling.

Tumour necrosis factor-α plays a significant role in the Aldara-induced skin inflammation in mice.

BACKGROUND: Recently, the Aldara-induced psoriasis-like skin inflammation model in mice has attracted increased attention, due to its dependence on the same immunological pathways and cell types as in human psoriasis. OBJECTIVES: To study the impact of constitutive deficiency of tumour necrosis factor (TNF)-α and its upstream regulator mitogen-activated protein kinase-activated protein kinase 2 (MAPKAPK-2, herein MK2) in the Aldara-induced psoriasis-like skin inflammation model. METHODS: TNF-α knockout (KO), MK2 KO and wild-type (WT) mice divided into separate groups received either 45-mg Aldara cream or control cream for 5 consecutive days. The skin inflammation was evaluated clinically, histologically, and by quantitative reverse transcription-polymerase chain reaction. RESULTS: We found that TNF-α KO mice developed significantly less skin inflammation compared with WT mice, as evaluated clinically and histologically. At the molecular level, we demonstrated that the Aldara-induced mRNA expression of the psoriasis-related inflammatory markers interleukin (IL)-17C, IL-23p19, IL-12p40, IL-17A, IL-22 and S100A8 was significantly decreased in TNF-α KO mice compared with WT mice. No significant difference in the mRNA expression of these inflammatory markers between MK2 KO mice and WT mice was found, although Aldara-treated MK2 KO mice showed a tendency towards a lower mRNA expression of IL-17A and IL-22 compared with WT mice. CONCLUSIONS: We were able to demonstrate significantly lower levels of inflammation in TNF-α KO mice compared with WT mice, supporting the use of this model in future studies characterizing the role of TNF-α in psoriasis.

Clinically relevant concentrations of lidocaine and ropivacaine inhibit TNFα-induced invasion of lung adenocarcinoma cells in vitro by blocking the activation of Akt and focal adhesion kinase.

BACKGROUND: Matrix-metalloproteinases (MMP) and cancer cell invasion are crucial for solid tumour metastasis. Important signalling events triggered by inflammatory cytokines, such as tumour necrosis factor α (TNFα), include Src-kinase-dependent activation of Akt and focal adhesion kinase (FAK) and phosphorylation of caveolin-1. Based on previous studies where we demonstrated amide-type local anaesthetics block TNFα-induced Src activation in malignant cells, we hypothesized that local anaesthetics might also inhibit the activation and/or phosphorylation of Akt, FAK and caveolin-1, thus attenuating MMP release and invasion of malignant cells. METHODS: NCI-H838 lung adenocarcinoma cells were incubated with ropivacaine or lidocaine (1 nM-100 µM) in absence/presence of TNFα (20 ng ml(-1)) for 20 min or 4 h, respectively. Activation/phosphorylation of Akt, FAK and caveolin-1 were evaluated by Western blot, and MMP-9 secretion was determined by enzyme-linked immunosorbent assay. Tumour cell migration (electrical wound-healing assay) and invasion were also assessed. RESULTS: Ropivacaine (1 nM-100 µM) and lidocaine (1-100 µM) significantly reduced TNFα-induced activation/phosphorylation of Akt, FAK and caveolin-1 in NCI-H838 cells. MMP-9 secretion triggered by TNFα was significantly attenuated by both lidocaine and ropivacaine (half-maximal inhibitory concentration [IC50]=3.29×10(-6) M for lidocaine; IC50=1.52×10(-10) M for ropivacaine). The TNFα-induced increase in invasion was completely blocked by both lidocaine (10 µM) and ropivacaine (1 µM). CONCLUSIONS: At clinically relevant concentrations both ropivacaine and lidocaine blocked tumour cell invasion and MMP-9 secretion by attenuating Src-dependent inflammatory signalling events. Although determined entirely in vitro, these findings provide significant insight into the potential mechanism by which local anaesthetics might diminish metastasis.

A novel protein with anti-metastasis activity on 4T1 carcinoma from medicinal fungus Cordyceps militaris.

Cordyceps militaris is a famous fungus used in traditional Chinese medicine for nearly one thousand years. And its fruiting body is known to possess anticancer and immunomodulatory activities. This study describes the isolation, characterization, and test of antitumor activity of a C. militaris protein, called here as "C. militaris immunoregulatory protein" (CMIP). CMIP was purified through a three-step chromatographic procedure. The MS analyses showed that CMIP corresponded to an uncharacterized protein (CCM_01955) in the C. militaris transcriptional database. Circular dichroism of CMIP revealed the composition of 35.5% ß-sheet, 18.5% α-helix, 17.0% turn and 29.0% random coil. No significant cytotoxicity of CMIP was observed on HeLa, HepG2 and 4T1 tumor cells. However, CMIP demonstrated anti-metastasis activity on a mouse model of 4T1 breast cancer lung metastasis. It reduced the number of tumor nodules in the lung of tumor-bearing mice and prolonged their survival time. Furthermore, proliferation of the 4T1 cells was inhibited by macrophage-CMIP conditioned media. And the mRNA levels of cytokines TNF-α, IL-1ß and IL-6 were increased significantly in peritoneal macrophages treated by CMIP. These results reveal the antitumor potential of CMIP, thus reinforcing the importance of biochemical prospecting of C. militaris.

Protection of Gastrointestinal Mucosa from Acute Heavy Alcohol Consumption: The Effect of Berberine and Its Correlation with TLR2, 4/IL1ß-TNFα Signaling.

The purpose of the present study is to confirm the protective effect of berberine (BBR) on gastrointestinal injury caused by acute heavy alcohol exposure, an effect that has not been reported previously. Our research details how BBR protects against gastrointestinal injuries from acute alcohol exposure using both in vivo and in vitro experiments. Acute high alcohol concentrations lead to obvious damage to the gastrointestinal mucosa, resulting in necrosis of the intestinal mucosa. Oral administration of BBR was able to significantly reduce this alcohol-induced damage, inhibit increases of alcohol-induced TNFα and IL-1ß expression in gastrointestinal mucosa as well as their upstream signals TLR2 and TLR4, and regulate cytokines that modulate tight junctions. Alcohol consumption is a popular human social behavior worldwide, and the present study reports a comprehensive mechanism by which BBR protects against gastrointestinal injuries from alcohol stress, providing people with a novel application of BBR.

Inhibitory effects of harpagoside on TNF-α-induced pro-inflammatory adipokine expression through PPAR-γ activation in 3T3-L1 adipocytes.

Obesity is closely associated with increased production of pro-inflammatory adipokines, including interleukin (IL)-6, plasminogen activator inhibitor (PAI)-1, and adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, which contribute to chronic and low-grade inflammation in adipose tissue. Harpagoside, a major iridoid glycoside present in devil's claw, has been reported to show anti-inflammatory activities by suppression of lipopolysaccharide (LPS)-induced production of inflammatory cytokines in murine macrophages. The present study is aimed to investigate the effects of harpagoside on both tumor necrosis factor (TNF)-α-induced inflammatory adipokine expression and its underlying signaling pathways in differentiated 3T3-L1 cells. Harpagoside significantly inhibited TNF-α-induced mRNA synthesis and protein production of the atherogenic adipokines including IL-6, PAI-1, and MCP-1. Further investigation of the molecular mechanism revealed that pretreatment with harpagoside activated peroxisome proliferator-activated receptor (PPAR)-γ. These findings suggest that the clinical application of medicinal plants which contain harpagoside may lead to a partial prevention of obesity-induced atherosclerosis by attenuating inflammatory responses.

Effect of glycosides based standardized fenugreek seed extract in bleomycin-induced pulmonary fibrosis in rats: Decisive role of Bax, Nrf2, NF-κB, Muc5ac, TNF-α and IL-1ß.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive multifactorial disease with limited therapeutic options. Glycosides based standardized fenugreek seed extract (SFSE-G) possesses potent anti-inflammatory and anti-oxidant property. AIM: To evaluate the efficacy of SFSE-G against bleomycin (BLM) induced pulmonary fibrosis by assessing behavioral, biochemical, molecular and ultrastructural changes in the laboratory rats. MATERIALS AND METHODS: IPF was induced in male Sprague-Dawley rats by single intratracheal BLM (6IU/kg) injection followed by SFSE-G (5, 10, 20 and 40mg/kg, p.o.) or methylprednisolone (10mg/kg, p.o.) treatment for 28day. Various parameters were analyzed in lung and bronchoalveolar lavage fluid (BALF) after 14 and 28days of the drug treatment. RESULTS: SFSE-G (20 and 40mg/kg, p.o.) administration significantly prevented the BLM induced alteration in body weight, lung index, lung function test and hematology. The altered total and differential cell count in BALF and blood was significantly prevented by SFSE-G treatment. The decreased peripheral blood oxygen content after BLM instillation was significantly increased by SFSE-G treatment. SFSE-G significantly enhanced the BALF and lung antioxidant status, through modulating the SOD, GSH, T-AOC, MDA, NO level and Nrf2, HO-1 mRNA expression. There was a significant reduction in lung 5-HT level by SFSE-G treatment. The altered mRNA expression of biomarkers of lung inflammation (TNF-α, IL-1ß, IL-6 and IL-8), fibrosis (TGF-ß, collagen-1, ET-1, Muc5ac, NF-κB, VEGF, Smad-3) and apoptosis (Bax, Bcl-2 and Caspase-3) were significantly prevented by SFSE-G treatment. BLM induced histological inflammatory and fibrotic insult in the lung were reduced by SFSE-G treatment. It also ameliorated BLM induced lung ultrastructural changes as observed by transmission electron microscopic studies. However, administration of SFSE-G (5mg/kg, p.o.) failed to show any protective effect against BLM-induced PF whereas SFSE-G (10mg/kg, p.o.) showed significant amelioration in BLM-induced PF except lung function test, BALF and lung antioxidant level. CONCLUSION: SFSE-G showed anti-fibrotic efficacy executed through induction of Nrf2, which in turn may modulate anti-inflammatory molecules, inhibit fibrogenic molecules and decreased apoptosis to ameliorate BLM induced pulmonary fibrosis.

Tumor necrosis factor alpha: a link between neuroinflammation and excitotoxicity.

Tumor necrosis factor alpha (TNF- α) is a proinflammatory cytokine that exerts both homeostatic and pathophysiological roles in the central nervous system. In pathological conditions, microglia release large amounts of TNF-α; this de novo production of TNF-α is an important component of the so-called neuroinflammatory response that is associated with several neurological disorders. In addition, TNF-α can potentiate glutamate-mediated cytotoxicity by two complementary mechanisms: indirectly, by inhibiting glutamate transport on astrocytes, and directly, by rapidly triggering the surface expression of Ca(+2) permeable-AMPA receptors and NMDA receptors, while decreasing inhibitory GABAA receptors on neurons. Thus, the net effect of TNF-α is to alter the balance of excitation and inhibition resulting in a higher synaptic excitatory/inhibitory ratio. This review summarizes the current knowledge of the cellular and molecular mechanisms by which TNF-α links the neuroinflammatory and excitotoxic processes that occur in several neurodegenerative diseases, but with a special emphasis on amyotrophic lateral sclerosis (ALS). As microglial activation and upregulation of TNF-α expression is a common feature of several CNS diseases, as well as chronic opioid exposure and neuropathic pain, modulating TNF-α signaling may represent a valuable target for intervention.