Inflammatory Lipopolysaccharide Research Articles

Gene Expression Analysis of Membrane Transport Proteins in Normal and Lipopolysaccharide-inflamed Rat Dental Pulp

IntroductionMembrane transport proteins (transporters) play a crucial role in the transmembrane uptake and/or efflux of various compounds such as inorganic ions, endogenous bioactive substances such as prostaglandins (PGs), and drugs such as nonsteroidal anti-inflammatory drugs. This study aimed to analyze mRNA expression of selected transporters related to drug disposition and PG transport in normal and lipopolysaccharide (LPS)-inflamed rat incisor pulp. MethodsPulp tissues were subjected to reverse transcription-polymerase chain reaction (PCR) detection for transporter isoforms belonging to organic anion transporting polypeptide (Oatp), organic anion transporter (Oat), organic cation transporter (Oct), multidrug resistance-associated protein (Mrp), and multidrug resistance protein (Mdr) families. The levels of mRNA expression for PG transporters (Oatp1a5, Oatp1b2, Oatp2a1, Oatp2b1, and Oatp3a1) were compared in normal and LPS-inflamed pulps by using real-time PCR. ResultsThe pulp tissue expressed mRNAs for various transporters belonging to the Oatp, Oat, Oct, Mrp, and Mdr families. LPS inflammation caused significant up-regulation of Oatp2a1 (P < .01) and significant down-regulation of Oatp1a5, Oatp2b1 (P < .01), and Oatp3a1 (P < .05). ConclusionsRat incisor dental pulp expressed mRNAs for various transporter isoforms. The levels of mRNA expression for PG transporters were significantly up-regulated or down-regulated in LPS-inflamed dental pulp.

Traditional medicine alpinetin inhibits the inflammatory response in Raw 264.7 cells and mouse models

Alpinetin, one of the main constituents of the seeds of Alpinia katsumadai Hayata, belonging to flavonoids, has been known to exhibit antibacterial, anti-inflammatory and other important therapeutic activities. The purpose of this study was to investigate the protection of alpinetin on inflammation in Lipopolysaccharide (LPS) stimulated Raw 264.7 cells and LPS induced vivo lung injury model. The effects of alpinetin on pro-inflammatory cytokines and signaling pathways were analyzed by enzyme-linked immunosorbent assay and Western blot. The results showed that alpinetin markedly inhibited the LPS- induced TNF-α, IL-6 and IL-1β production both in vitro and vivo. Furthermore, alpinetin blocked the phosphorylation of IκBα protein, p65, p38 and extracellular signal-regulated kinase (ERK) in LPS stimulated RAW 264.7 cells. From in vivo study, it was also observed that alpinetin attenuated lung histopathologic changes in mouse models. These results suggest that alpinetin potentially decreases the inflammation in vitro and vivo, and might be a therapeutic agent against inflammatory diseases.

Eupatilin inhibits lipopolysaccharide-induced expression of inflammatory mediators in macrophages

Aims Eupatilin (5,7-dihydroxy-3,4,6-trimethoxyflavone) is a pharmacologically active ingredients in Stillen TM, a drug for the gastric mucosal ulcers. Eupatilin has been known to possess anti-peptic, anti-cancer, and anti-allergy activity. In this report, we defined the effect of eupatilin on the endotoxin-induced inflammation in lipopolysaccharide (LPS)-stimulated macrophages. Main methods Mouse J774A.1 cell line and mouse peritoneal macrophages were used. Gene expression and production of inflammatory mediators were determined by real-time PCR and Western blot. Key findings Eupatilin dose-dependently suppressed LPS-induced expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO). Eupatilin decreased LPS-induced expression of inflammatory mediators and pro-inflammatory cytokines such as cyclooxygenase-2, monocyte chemoattractant protein-1, tumor necrosis factor-α, interleukin (IL)-1β and IL-6. In addition, this suppression of inflammatory mediators was nuclear factor (NF)-κB dependent. Significance Our findings imply that eupatilin suppresses inflammatory responses by the inhibition of NF-κB signaling pathway, and downstream inflammatory mediators in endotoxin-stimulated macrophages.

Membrane-rich milk fat diet provides protection against gastrointestinal leakiness in mice treated with lipopolysaccharide

Milk fat globule membrane is a protein-lipid complex that may strengthen the gut barrier. The main objective of this study was to assess the ability of a membrane-rich milk fat diet to promote the integrity of the gut barrier and to decrease systemic inflammation in lipopolysaccharide (LPS)-challenged mice. Animals were randomly assigned to one of 2 American Institute of Nutrition (AIN)-76A formulations differing only in fat source: control diet (corn oil) and milk fat diet (anhydrous milk fat with 10% milk fat globule membrane). Each diet contained 12% calories from fat. Mice were fed diets for 5 wk, then injected with vehicle or LPS (10mg/kg of BW) and gavaged with dextran-fluorescein to assess gut barrier integrity. Serum was assayed for fluorescence 24h after gavage, and 16 serum cytokines were measured to assess the inflammatory response. Gut permeability was 1.8-fold higher in LPS-challenged mice fed the control diet compared with the milk fat diet. Furthermore, mice fed the milk fat diet and injected with LPS had lower serum levels of IL-6, IL-10, IL-17, monocyte chemotactic protein (MCP)-1, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and IL-3 compared with LPS-injected mice fed the control diet. The results indicate that the membrane-rich milk fat diet decreases the inflammatory response to a systemic LPS challenge compared with corn oil, and the effect coincides with decreased gut permeability.

Inflammatory Induction of Human Resistin Causes Insulin Resistance in Endotoxemic Mice

OBJECTIVEAlthough adipocyte-derived murine resistin links insulin resistance to obesity, the role of human resistin, predominantly expressed in mononuclear cells and induced by inflammatory signals, remains unclear. Given the mounting evidence that obesity and type 2 diabetes are inflammatory diseases, we sought to determine the relationship between inflammatory increases in human resistin and insulin resistance.RESEARCH DESIGN AND METHODSTo investigate the role of human resistin on glucose homeostasis in inflammatory states, we generated mice lacking murine resistin but transgenic for a bacterial artificial chromosome containing human resistin (BAC-Retn), whose expression was similar to that in humans. The metabolic and molecular phenotypes of BAC-Retn mice were assessed after acute and chronic endotoxemia (i.e., exposure to inflammatory lipopolysaccharide).RESULTSWe found that BAC-Retn mice have circulating resistin levels within the normal human range, and similar to humans, lipopolysaccharide markedly increased serum resistin levels. Acute endotoxemia caused hypoglycemia in mice lacking murine resistin, and this was attenuated in BAC-Retn mice. In addition, BAC-Retn mice developed severe hepatic insulin resistance under chronic endotoxemia, accompanied by increased inflammatory responses in liver and skeletal muscle.CONCLUSIONSThese results strongly support the role of human resistin in the development of insulin resistance in inflammation. Thus, human resistin may link insulin resistance to inflammatory diseases such as obesity, type 2 diabetes, and atherosclerosis.

Lipopolysaccharide attenuates phrenic long-term facilitation following acute intermittent hypoxia

Lipopolysaccharide (LPS) induces inflammatory responses, including microglial activation in the central nervous system. Since LPS impairs certain forms of hippocampal and spinal neuroplasticity, we hypothesized that LPS would impair phrenic long-term facilitation (pLTF) following acute intermittent hypoxia (AIH) in outbred Sprague-Dawley (SD) and inbred Lewis (L) rats. Approximately 3h following a single LPS injection (i.p.), the phrenic response during hypoxic episodes is reduced in both rat strains versus vehicle treated, control rats (SD: 84 ± 7% vs. 128 ± 14% baseline for control, p < 0.05; L: 62 ± 10% vs. 90 ± 9% baseline for control, p < 0.05). At 60 min post-AIH, pLTF is also diminished by LPS in both strains: (SD: 22 ± 5% vs. 73.5 ± 14% baseline for control, p < 0.05; L: 18 ± 15% vs. 56 ± 8% baseline for control, p < 0.05). LPS alone does not affect phrenic burst frequency in either rat strain, suggesting that acute LPS injection has minimal effect on brainstem respiratory rhythm generation. Thus, systemic LPS injections and (presumptive) inflammation impair pLTF, a form of spinal neuroplasticity in respiratory motor control. These results suggest that ongoing infection or inflammation must be carefully considered in studies of respiratory plasticity, or during attempts to harness spinal plasticity as a therapeutic tool in the treatment of respiratory insufficiency, such as spinal cord injury.

Common bean (Phaseolus vulgaris L.) hydrolysates inhibit inflammation in LPS-induced macrophages through suppression of NF-κB pathways

The objectives of this study were to evaluate the antioxidant capacity of protein hydrolysates of the common bean (Phaseolus vulgaris L.) varieties Negro 8025 and Pinto Durango and determine their effect on the markers of inflammation in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Cell viability was determined and the percentage of viable cells was calculated and concentrations that allowed >80% cell viability were used to determine the markers of inflammation. Alcalase hydrolysates and pepsin–pancreatin hydrolysates showed the highest antioxidant capacity after 80 and 120min of hydrolysis, respectively. Alcalase hydrolysates of the common bean Pinto Durango at 120min inhibited inflammation, with IC50 values of 34.9±0.3, 13.9±0.3, 5.0±0.1 and 3.7±0.2μM, while var. Negro needed 43.6±0.2, 61.3±0.3, 14.2±0.3 and 48.2±0.1μM for the inhibition of cyclooxygenase-2 expression, prostaglandin E2 production, inducible nitric oxide synthase expression and nitric oxide production, respectively. Also, hydrolysates significantly inhibited the transactivation of NF-κB and the nuclear translocation of the NF-κB p65 subunit. In conclusion, hydrolysates from the common bean can be used to combat inflammatory and oxidative-associated diseases.

A Mouse Macrophage Lipidome

We report the lipidomic response of the murine macrophage RAW cell line to Kdo(2)-lipid A, the active component of an inflammatory lipopolysaccharide functioning as a selective TLR4 agonist and compactin, a statin inhibitor of cholesterol biosynthesis. Analyses of lipid molecular species by dynamic quantitative mass spectrometry and concomitant transcriptomic measurements define the lipidome and demonstrate immediate responses in fatty acid metabolism represented by increases in eicosanoid synthesis and delayed responses characterized by sphingolipid and sterol biosynthesis. Lipid remodeling of glycerolipids, glycerophospholipids, and prenols also take place, indicating that activation of the innate immune system by inflammatory mediators leads to alterations in a majority of mammalian lipid categories, including unanticipated effects of a statin drug. Our studies provide a systems-level view of lipid metabolism and reveal significant connections between lipid and cell signaling and biochemical pathways that contribute to innate immune responses and to pharmacological perturbations.

Pharmacodynamics of tepoxalin, sodium-salicylate and ketoprofen in an intravenous lipopolysaccharide inflammation model in broiler chickens

The pharmacodynamic properties of tepoxalin, Na-salicylate and ketoprofen were determined in an intravenous lipopolysaccharide (LPS) inflammation model in broiler chickens. The drugs were administered orally at a dose of 30, 50 and 3 mg/kg, respectively. LPS administration induces an increase in the intracellular expression of interleukin (IL)-1β and IL-6 and the secreted IL-6 plasma concentration. Furthermore, an elevation in body temperature is noted. Despite pretreatment with a single dose of the drugs and LPS administration on the T(max) of the drug after a second dose, no decrease was seen in systemic IL-6 levels. The intracellular expression of IL-1β in the heterophils was slightly decreased if LPS was administered in combination with each of the three drugs. Tepoxalin and Na-salicylate administration had no significant effect on the LPS-induced increase in prostaglandin E(2) plasma concentration, in contrast to ketoprofen. None of the three drugs were able to influence the elevation in body temperature after LPS administration. The pharmacokinetic properties of Na-salicylate and ketoprofen were not altered in combination with LPS administration. However, LPS significantly decreased the AUC(0→6 h) of the active metabolite of tepoxalin, RWJ-20142, indicating a perfusion-limited elimination for this molecule.

Dietary milk fat globule membrane (MFGM) provides protection against gastrointestinal stress in mice treated with lipopolysaccharide (LPS)

Inflammation is known to decrease gut barrier integrity. MFGM is a protein‐lipid complex containing phospholipids and membrane glycoproteins that may increase gut barrier properties. We sought to determine if MFGM enhances gut barrier integrity and decreases inflammation in LPS challenged mice. Mice were randomly assigned to one of two diets differing only in fat source: control diet (AIN‐76A, corn‐oil fat source) and AIN‐76A diet (equal amount of MFGM and anhydrous milk fat as the fat source). Mice were fed diets for 5 weeks then injected with saline control or LPS (10 mg/kg BW) and gavaged with dextran‐fluorescein (D‐FITC) to assess gut barrier integrity. Serum samples were assayed for D‐FITC 24 h after gavage, and a panel of 16 cytokine concentrations was measured to determine inflammatory response. Gut permeability was 45% less in LPS challenged mice fed MFGM diet compared to mice fed control diets (P &lt; 0.05). LPS injection did not increase gut permeability compared to saline injection in mice fed MFGM diets. Conversely, LPS injection of mice fed control diets significantly increased gut permeability compared to saline injected cohorts (P &lt; 0.05). LPS injected mice fed MFGM diets had lower serum levels of IL‐6, IL‐10, IL‐17, MCP‐1, IFNγ, and TNFα; compared to LPS injected mice fed control diets (P &lt; 0.05). Our results suggest that MFGM inhibits the inflammatory response and protects against LPS induced gut permeability.Grant Funding Source: Dairy Management Incorporated

Characterization of an intravenous lipopolysaccharide inflammation model in broiler chickens

Intravenous administration of lipopolysaccharide (LPS) from Escherichia coli O127:B8 at a dose of 1,500,000 u/kg body weight evoked a hypothermic response followed by a fever phase in 5-week-old broiler chickens. The hypothermic phase coincided with a severe decrease in blood pressure. We assume that this decrease in blood pressure is, at least partly, responsible for the hypothermic phase of the body temperature curve. LPS administration also caused a decrease in circulating white blood cells. The heterophils were predominantly sequestered in the lungs. In LPS-treated chickens, far more apoptotic leukocytes were present in the circulation, compared with control chickens. The molecular players responsible for the LPS-induced inflammatory response could be TL1A, IL-1β and IL-6, since a slight increase in their mRNA levels in white blood cells was already seen 1 h after LPS administration. In accordance with these observations, the levels of secreted IL-6 were maximal 3 h after LPS administration. These parameters characterize this LPS-induced inflammation model in broiler chickens.

Modulation of Inflammatory Responses by Green and Black Tea Extracts in LPS‐Induced RAW 264.7 Cells

Tea is produced from the leaves of the Camellia sinensis plant and is one of the most popular beverages in the world. Tea polyphenols are thought to have chemopreventive and cardioprotective effects due to their ability to suppress inflammation. The goal of this study is to measure markers of inflammation in lipopolysaccharide (LPS) ‐ stimulated RAW 264.7 mouse macrophage cells in the presence or absence of varying concentrations of green tea (GT) and black tea (BT) to determine their effects on the inflammatory response. Tea phenolic contents were measured using the Folin‐Ciocalteu reagent (GT had a higher total phenol content than BT). Cell viability was assessed using the Trypan Blue and MTT assays. Prostaglandin E2 (PGE2) concentration was determined by ELISA (GT and BT increased PGE2 formation relative to controls.). The BCA assay was done to determine total protein concentration for Western blotting. The presence of cyclooxygenase‐2 (COX‐2) will be detected with Western Blotting. Based on preliminary data, we predict that the teas will modify the inflammatory response, and that GT will have a greater effect than BT due to differences in tea composition. This project was supported by the State of North Carolina.

Rho kinase inhibition attenuates LPS-induced renal failure in mice in part by attenuation of NF-κB p65 signaling

Rho kinase signaling regulates inflammatory cell migration and chemokine production. We therefore investigated the mechanisms of Rho-kinase-dependent inflammation in lipopolysaccharide (LPS)-induced renal failure. C57/BL6 mice received intraperitoneal LPS with or without daily treatment with specific Rho kinase inhibitors (Y-27632 or HA-1077; 5 mg/kg). Rho kinase inhibitors were applied in a preventive (12 or 1 h before LPS) or a therapeutic (6 h after LPS) scheme. Both protected renal function and decreased tubular injury in LPS-treated mice. Enhanced Rho kinase activity was inhibited by HA-1077 in capillary endothelial cells, inflammatory cells, and tubuli by analysis of Rho kinase substrate phosphorylation. Early neutrophil influx was reduced by HA-1077 without reduction of the proinflammatory cytokine TNFalpha. In contrast, HA-1077 decreased the influx of monocytes/macrophages coinciding with reduced expression of the NF-kappaB-regulated chemokines CCL5 and CCL2. We therefore examined NF-kappaB signal transduction and found that NF-kappaB p65 phosphorylation and nuclear translocation were reduced by Rho kinase inhibition. IkappaBalpha degradation was not altered during the first 6 h but was reduced by HA-1077 at later time points. NF-kappaB p50-deficient mice were similarly protected from renal injury by Rho kinase inhibition further supporting the prominent role for p65 in Rho kinase inhibition. Together, these data suggest that Rho kinase inhibition by preventive or therapeutic treatment effectively reduced endotoxic kidney injury in part by attenuation of NF-kappaB p65 activation.

Identification and validation of housekeeping genes as internal control for gene expression in an intravenous LPS inflammation model in chickens

Real-time PCR has become a powerful tool for the detection of inflammatory parameters, including cytokines. Reference or housekeeping genes are used for the normalization of real-time RT-PCR results. In order to obtain reliable results, the stability of these housekeeping genes needs to be determined. In this study the stability of five genes, including β-actin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), hypoxanthine phophoribosyl-transferase (HPRT), ubiquitin (UB) and glucose-6-phosphate dehydrogenase (G6PDH), was determined in a lipopolysaccharide inflammation model in chickens. β-Actin appeared to be the most stable single gene in our model. Because the use of a single gene for normalization can lead to relatively large errors, the use of the geometric mean of multiple reference genes or normalization factor is preferred. The most stable combination for gene expression analysis in this lipopolysaccharide inflammation model in chickens is G6PDH and UB, since their correlation coefficients were 0.953 and 0.969, respectively (BestKeeper) and an M value of 0.34 and a low V 2/3 value of 0.155 (geNorm) were obtained. The use of HPRT and GAPDH should be avoided. The stable housekeeping genes, G6PDH and UB together, can be used to normalize the expression of pro-inflammatory cytokines in a lipopolysaccharide inflammation model in chickens.

ROLE OF BACTERIAL ENDOTOXIN IN CHRONIC HEART FAILURE

Proinflammatory cytokines are now thought to play a key role in the pathophysiology of chronic heart failure, driving both symptomatic presentation and disease progression. We propose that this proinflammatory state, in turn, may be sustained through a chronic release of enterically derived bacterial endotoxin. Human trials have indicated that bacterial decontamination of the gut with concomitant decrease in lipopolysaccharide (LPS) has a positive outcome on heart disease patients. Antiendotoxin antibodies may thus represent therapeutic agents in this setting. Previously, antiendotoxin antibodies were targeted to the inner hydrophobic lipid A moiety of endotoxin in an attempt to neutralize its toxicity. These antibodies failed because they lacked specificity and bound to LPS weakly. In contrast, our studies on antiendotoxin antibodies have revealed that antibodies targeted to the hydrophilic oligosaccharides of the endotoxin have the potential to bind specifically with high affinity. Development of immunotherapeutics that can reduce systemic LPS or other agents, such as bactericidal/permeability-increasing protein that can neutralize LPS and limit inflammation safely, will enable the role of LPS in chronic heart failure to be elucidated and may pave the way to develop a new generation of effective therapeutic agents that may be directed to the treatment of chronic heart failure.

DIETARY GANGLIOSIDE INHIBITS ACUTE INFLAMMATORY SIGNALS IN INTESTINAL MUCOSA AND BLOOD INDUCED BY SYSTEMIC INFLAMMATION OF ESCHERICHIA COLI LIPOPOLYSACCHARIDE

Our previous study demonstrated that feeding ganglioside increased total ganglioside content while decreasing cholesterol and caveolin-1 content in developing rat intestinal lipid microdomains. Cholesterol or caveolin depletion in membranes inhibits inflammatory signaling by disrupting microdomain structure. We hypothesized that dietary ganglioside-induced reduction in cholesterol content will reduce proinflammatory mediators in the intestinal mucosa after acute exposure to bacterial endotoxin. Weanling rats were fed semipurified diets with 0.1% (wt/wt of total fat) gangliosides (treatment) or without ganglioside (control). After 2 weeks of feeding, half of animals from each diet group were injected with saline or lipopolysaccharide (LPS) endotoxin (Escherichia coli serotype O111:B4, intraperitoneal, 3 mg/kg body weight) to induce acute gut inflammation. Intestinal mucosa and blood were collected after 6 h. The effect of dietary ganglioside on proinflammatory mediators including cholesterol, platelet-activating factor, prostaglandin E2, leukotriene B4 (LTB4), interleukin-1beta (IL-1beta), and tumor necrosis factor-alpha (TNF-alpha) was determined in inflamed mucosa and blood. Feeding animals the control diet increased cholesterol content in intestinal lipid microdomains by 92% after LPS injection compared with saline injection. Animals fed the ganglioside diet significantly decreased cholesterol content in lipid microdomains by 60% compared with animals fed the control diet. Feeding animals the ganglioside diet increased total ganglioside content by 90% while decreasing platelet-activating factor content by 45% in the inflamed mucosa by acute systemic exposure to LPS compared with animals fed the control diet. When animals were fed the ganglioside diet, the levels of prostaglandin E2, LTB4, IL-1beta, and TNF-alpha were lower in inflamed mucosa, and LTB4, IL-1beta, and TNF-alpha were decreased in plasma by 41%, 58%, and 55% compared with control animals, respectively. The present study demonstrates that dietary gangliosides inhibit proinflammatory signals in the intestine and blood induced by acute inflammation of LPS and suggests therapeutic potential in the treatment and management of acute local and systemic inflammatory diseases.

Food-derived phytochemicals ‘Curcumin’ and ‘Resveratrol’ counteract the catabolic effects of inflammatory lipopolysaccharides: studies on in vitro models of canine and porcine arthritis

Osteoarthritis (OA) and Osteochondritis Dissecans (OCD) are osteoarticular disorders that cause leg weakness, lameness, pain and suffering in companion animals, some farm animals and humans. OA is one of the most common age-related osteoarticular disorders in humans and dogs. In pigs, both OA and OCD are thought to arise from changes in the articular cartilage and growth plates within the synovial joints causing structural damage to joint tissues. Since these changes are not observed in the slow maturing wild boar, they are suggested to be a result of the modern intensive pig production industry which has very successfully selected pigs for rapid growth rates, large muscle mass and efficient feed conversion placing increased weight and mechanical stress on growth plates. The aim of this study was to establish canine and porcine articular cartilage explant models which are essentially tissue culture techniques for isolating and maintaining cartilage tissue ex vivo for subsequent assessment of potentially beneficial effects of specific phytonutrients. Bacterial lipopolysaccharide (LPS) was used as a catabolic mediator to create a culture model of joint inflammation mimicking the events that occur in late stages of OA and OCD. We then performed assays to determine if the dietary phytochemical ‘curcumin’ (derived from Curcuma longa) and the polyphenolic phytoalexin stilbene ‘resveratrol’ (found in red grapes, red wine, peanuts and some berries) are able to counteract the catabolic effects of LPS by inhibiting LPS stimulated release of cartilage matrix glycosaminoglycans (GAGs).

Transient Receptor Potential Vanilloid Subfamily 1 is Essential for the Generation of Noxious Bladder Input and Bladder Overactivity in Cystitis

We evaluated the role of transient receptor potential vanilloid subfamily 1 for the generation of noxious bladder input and bladder overactivity associated with cystitis. Spinal c-fos expression triggered by innocuous bladder distention (10 cm water) was studied in sham and lipopolysaccharide inflamed transient receptor potential vanilloid subfamily 1 +/+ and -/- mice. Bladder reflex activity was studied using urethane anesthesia in sham and lipopolysaccharide inflamed transient receptor potential vanilloid subfamily 1 +/+ and -/- mice. Inflammatory changes in the bladder of transient receptor potential vanilloid subfamily 1 +/+ and -/- mice were identical. Bladder distention in sham inflamed +/+ mice induced a mean +/- SD of 4 +/- 2 Fos cells per section. Bladder distention after lipopolysaccharide inflammation increased Fos cells to 34 +/- 5 (p <0.001). The number of Fos cells after bladder distention in sham and lipopolysaccharide inflamed -/- mice was similar (2 +/- 1 and 2 +/- 1, respectively, p >0.05). During saline infusion of sham inflamed bladders in +/+ mice 0.46 +/- 0.14 contractions per minute were documented. In lipopolysaccharide inflamed +/+ mice that frequency was increased to 1.13 +/- 0.12 contractions per minute (p <0.001). In sham and lipopolysaccharide inflamed -/- mice bladder frequency was similar (0.47 +/- 0.08 and 0.61 +/- 0.10, respectively, p >0.05). Our data demonstrate that transient receptor potential vanilloid subfamily 1 is essential for the generation of noxious bladder input and bladder overactivity associated with cystitis.

Parasitic helminths tip the balance: potential anti‐inflammatory therapies

Parasitic helminths are worms that are classified within the phyla Nematoda (roundworms) and Platyhelminthes (flatworms) (see Table 1). Some nematode species, Filariae being a notable example, are able to coexist with their human host for decades. Interestingly, although millions suffer severe morbidity, a lower incidence of allergy and autoimmune disease has been reported in infected individuals.1,2 Viral and bacterial infections, and autoimmune diseases such as type I diabetes and multiple sclerosis typically induce a T helper type 1 (Th1) pro-inflammatory response producing cytokines such as interleukin-12 (IL-12), interferon-γ (IFN-γ) and tumour necrosis factor-α (TNF-α). Chronic parasitic helminth infection is associated with high levels of immunoglobulin E (IgE), eosinophilia, mastocytosis and a predominantly Th2 immune response. This Th2 response is characterized by production of IL-4, IL-5, IL-10 and IL-13,3 a cytokine pattern that is also linked to an anti-inflammatory phenotype. There is evidence that a Th2 response is protective in the case of gastrointestinal nematodes.4 However, there is also overwhelming evidence from other helminth infections that a Th2 response may provide an anti-inflammatory regulatory environment.1,5 The counter-regulatory effects of Th1 and Th2 cytokines can be seen in many immune responses and there is strong evidence that the Th2 response generated by helminths can down-regulate Th1 responsiveness to other infections.

Effects of the Combined Treatment of Naloxone and Indomethacin on Catecholamines and Behavior After Intranigral Lipopolysaccharide Injection

The present study examined effects of the combined administration of naloxone (NX) and indomethacin (IM) on nigrostriatal catecholamines and locomotor activity after intranigral lipopolysaccharide (LPS) injection in Sprague-Dawley rats. NX plus IM was given 3 days after LPS injection; it significantly (P < .05) reversed LPS inflammation on nigrostriatal dopamine (DA) and nigral serotonin (5-HT) and nigral homovanillic acid (HVA)/DA ratio and nigrostriatal 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio. It also tended to ameliorate the locomotor hyperactivity. However, NX plus IM given 30 min before LPS could not satisfactorily protect against LPS's damage both biochemically and behaviorally. These results reveal that NX plus IM may protect against LPS on DA, 5-HT, and motor function after LPS injection but not before. Thus it suggests that the combined treatment of NX and IM gives a potent therapy, but not prevention, of LPS-induced inflammation and also protect nigrostriatal dopaminergic and serotoninergic systems against LPS in rats.