Typhonium giganteum Lectin Exerts A Pro-Inflammatory Effect on RAW 264.7 via ROS and The NF-κB Signaling Pathway.

Typhonii rhizoma, a widely used herb in traditional Chinese medicine, has acute irritating toxicity related to Typhonium giganteum lectin (TGL). TGL exhibits acute inflammatory effects, but the underlying molecular mechanisms are largely unknown. This paper is designed to assess the pro-inflammatory response of TGL on RAW 264.7 cells. RAW 264.7 treated with 6.25, 12.5, 25, and 50 µg/mL TGL showed elevated levels of inflammatory factors (TNF-α, IL-1ß) and of p-IκB and p-p65, all dose-dependent, indicating that TGL had a substantial inflammatory effect and mobilized the nuclear factor-κB (NF-κB) pathway. All four TGL treatments also induced the up-regulation of reactive oxygen species (ROS) and cytosolic free Ca2+ and down-regulation of mitochondrial membrane potential (MMP). The production of cytokines and p-IκB, p-p65 were reduced by N-acetylcysteine (NAC), an ROS scavenger, which somewhat abrogated ROS production. The results showed the TGL-activated inflammatory signaling pathway NF-κB to be associated with the overproduction of ROS. Moreover, 50 µg/mL treatment with TGL led to cell apoptosis after 1 h and increased necrosis over time. These results provided potential molecular mechanisms for the observed inflammatory response to TGL including up-regulation of ROS and cytosolic free Ca2+, down-regulation of MMP, the mobilization of the NF-κB pathway, and the subsequent overproduction of pro-inflammatory factors resulting in apoptosis. Long-term stimulation with TGL resulted in strong toxic effects related to inflammation that induced necrosis in macrophages.

Nutrients can modulate the adiponectin concentrations in apparently healthy young adults / Los nutrientes pueden modular las concentraciones de adiponectina en adultos jóvenes aparentemente sanos

Introduction: Adiponectin, an adipocyte derived peptide, has anti-inflammatory and antiatherogenic effects, and improves insulin sensitivity. However, little is known about dietary predictors and their interactions with lifestyle on adiponectin concentrations, in apparently healthy young adults. Objective: To evaluate the associations between plasma concentrations of adiponectin with dietary components and lifestyle in apparently healthy young adults. Methods: Anthropometric and body composition, systolic and diastolic blood pressure, diet and lifestyle data of 157 healthy young adults, aged 18 and 35, were collected and analyzed. Blood samples were collected after fasting for 12 hours to determine adiponectin concentrations. Dietary and anthropometric indexes were calculated and analyzed. Results: Adiponectin concentrations were significantly higher for women compared to men; and there was an indirect and significant correlation between adiponectin concentrations with BMI. There was a significant association between adiponectin concentrations with the healthy eating index, calories, lipids, proteins, fibers, riboflavin, and phosphorus, among others; and a tendency with carbohydrates and niacin. In multiple linear regression analysis, fiber and riboflavin (r2 = 0.0928; p = 0.0013) and carbohydrates and phosphorus were associated with the concentrations of adiponectin. The association with carbohydrates and phosphorus suffered interaction with gender (r2 = 0.2400; p < 0.0001), as well as the association with phosphorus also suffered interaction with physical activity (r2 = 0.1275; p = 0.0003) Conclusion: Plasma concentrations of adiponectin, in healthy young adults, seem to be modulated by components of diet depending on gender and physical activity (AU)

Introducción: la adiponectina, un péptido derivado de los adipocitos, tiene efectos antiinflamatorios y antiaterogénicos, y mejora la sensibilidad a la insulina. Sin embargo, se conoce poco sobre los predictores de la dieta, así como sobre las interacciones con el estilo de vida de las concentraciones de adiponectina en adultos jóvenes aparentemente sanos. Objetivo: evaluar la asociación entre las concentraciones plasmáticas de adiponectina con los componentes de la dieta y estilo de vida en los adultos jóvenes aparentemente sanos. Métodos: fueron recogidos y analizados datos antropométricos y de composición corporal, presión arterial sistólica y diastólica, datos de la dieta y del estilo de vida de 157 adultos jóvenes sanos, de entre 18 y 35 años de edad. Se tomaron muestras de sangre después de un ayuno de 12 horas para determinar las concentraciones de adiponectina y se calcularon y analizaron los índices dietéticos y antropométricos. Resultados: las concentraciones de adiponectina fueron significativamente mayores para las mujeres en comparación con los hombres; y había una correlación indirecta y significativa entre las concentraciones de adiponectina con el IMC. Hubo una asociación significativa entre las concentraciones de adiponectina con el índice de alimentación saludable, calorías, lípidos, proteínas, fibras, riboflavina y fósforo, entre otros; y una tendencia con los hidratos de carbono y niacina. En el análisis de regresión lineal múltiple, la fibra y la riboflavina (r2 = 0,0928, p = 0,0013) y los hidratos de carbono y el fósforo se asociaron con las concentraciones de adiponectina. La asociación con los hidratos de carbono y fósforo sufrió interacción con el género (r2 = 0,2400, p < 0,0001), así como la asociación con el fósforo también sufrió interacción con la actividad física (r2 = 0,1275, p = 0,0003). Conclusión: Las concentraciones plasmáticas de adiponectina, en adultos jóvenes aparentemente sanos, parecen estar moduladas por componentes de la dieta en forma dependiente de género y de la actividad física (AU)

Mono- and Cocultures of Bronchial and Alveolar Epithelial Cells Respond Differently to Proinflammatory Stimuli and Their Modulation by Salbutamol and Budesonide.

The aim of this study was to investigate the changes in transport and effectiveness of salbutamol sulfate (SAL) and budesonide (BD) following stimulation with transforming growth factor-ß (TGF-ß) in mono- and coculture models of bronchial and alveolar epithelium. Primary bronchial and alveolar epithelial cells, grown at air interface on filters, either as monocultures or in coculture with airway smooth muscle cells or alveolar macrophages, respectively, were stimulated with TGF-ß. The biological response was modulated by depositing aerosolized SAL and BD on bronchial and alveolar models, respectively. Barrier integrity, permeability to fluorescein-Na, transport of the deposited drug, and the pharmacological response to SAL (cAMP and IL-8 levels) or BD (IL-6 and -8 levels) were measured. While stimulation with TGF-ß did not have any significant effect on the transepithelial electrical resistance and permeability to fluorescein-Na in mono- and coculture models, transport of SAL and BD were affected in cultures from some of the patients (6 out of 12 for bronchial and 2 out of 4 for alveolar cells). The bronchial coculture showed a better responsiveness to SAL in terms of cAMP release than the monoculture. In contrast, the difference between alveolar mono- and cocultures to TGF-ß mediated interleukin release and its modulation by BD was less pronounced. Our data point to intrinsic differences in the transport of, and responsiveness to, SAL and BD when epithelial cell cultures originate from different patients. Moreover, if the biological responses (e.g., IL-8, cAMP) involve communication between different cell types, coculture models are more relevant to measure such effects than monocultures.

Vitamin D attenuates pro-inflammatory TNF-alfa cytokine expression by inhibiting NF-kB/p65 signaling in hypertrophied rat hearts

A growing body of evidence suggests that immune activation and inflammatory mediators may play a key role in the development and progression of left ventricle (LV) hypertrophy. The present study was designed to test the hypothesis that the cardioprotective effect of cholecalciferol (Vit-D3) is mediated via the regulation of messenger RNA (mRNA) expression of pro-inflammatory cytokines. Rats were randomly divided into four groups: control group received normal saline (0.9 % NaCl) i.p. for 14 days; Vit-D3 group received Vit-D3 at a dose of 12 μg/kg/day by gavage for 14 days; ISO group received saline for 7 days, and at day 7, ISO (5 mg/kg/day) was injected i.p. for 7 consecutive days to induce cardiac hypertrophy; and Vit-D3 + ISO group was treated with Vit-D3 for 14 days, and at day 7, ISO was administered for 7 consecutive days. Heart/body weight ratio, troponin-T, creatine kinase-MB, and tumor necrosis factor-alfa (TNF-alfa) levels of LV tissue were estimated. Levels of mRNA expression of NF-кB (NF-кB)/p65 and inhibitory kappa B (IкB)-alfa were determined by real-time PCR. Vit-D3 administration before and during induction of cardiac hypertrophy significantly reduced (P < 0.001) cardiac biomarkers. The histopathological examination further confirmed these results. In addition, Vit-D3 significantly decreased (P < 0.001) NF-кB-p65mRNA expression and increased (P < 0.01) IкB-alfa mRNA expression in LV tissues compared to ISO group. Based on these findings, it was concluded that the administration of cholecalciferol markedly attenuated the development of ISO-induced cardiac hypertrophy likely through downregulation ofTNF-alfa /NF-кb/p65 signaling pathways. However, it should be pointed out that other signaling pathways may contribute to the cardioprotective effect of Vit-D3 which requires further investigation

A signature of microRNA-155 in the pathogenesis of diabetic complications

The current study was designed to explore the potential involvement of miR-155 in the pathogenesis of diabetes complications. Male rats were divided into control and diabetic groups (n = 6). Type 2 diabetes was induced by a single-dose injection of nicotinamide (110 mg/kg; intraperitoneal (i.p.)), 15 min before injection of streptozotocin (STZ; 50 mg/kg; i.p.) in 12-h fasted rats. Two months after induction of diabetes, the rats were sacrificed for subsequent measurements. The nuclear factor kappa B (NF-κB) activity was higher in diabetic peripheral blood mononuclear cells (PBMCs), aorta, heart, kidney, liver, and sciatic nerve, than the control counterparts. Also, apoptosis rate was increased in these tissues, except the aorta. NF-κB messenger RNA (mRNA) expression level was higher in the kidney, heart, PBMCs, and sciatic nerve of diabetic rats than their control counterparts. Except the liver, the miR-155 expression level was significantly decreased in diabetic kidney, heart, aorta, PBMCs, and sciatic nerve versus the controls. Moreover, the expression of miR-155 was negatively correlated with NF-κB activity and apoptosis rate. These results suggest that changes in the expression of miR-155 may participate in the pathogenesis of diabetes-related complications, but causal relationship between miR-155 dysregulation and diabetic complications is unknown

"Free" copper: a new endogenous chemical mediator of inflammation in birds.

For acceptance of any chemical agent as an endogenous chemical mediator of inflammation, the agent in question must fulfill some biological requirements which are (a) it should be ubiquitously present in tissues in inactive form, (b) it should be activated during process of inflammation whose increase should be identifiable, (c) it should induce or amplify some events of inflammation, (d) there must be some natural inhibitor of such active form in tissues, (e) it should be able to induce inflammatory reaction after exogenous injection, (f) such reaction should be inhibited by exogenous use of their antagonists, and (g) it should be amplified by use of agonists. Copper in its protein free or protein bound form are reported to act as pathogenic factor in inflammatory processes due to oxidative stress. But their role as endogenous chemical mediator of inflammation does not appear to be investigated thoroughly in light of abovementioned biological criterion of mediator. Present study aims at thorough exploration on role of free copper as endogenous chemical mediator of inflammation in light of above facts. It was done by estimation of total copper, protein-bound copper, and free copper along with estimation of free radical generation, increase in vascular permeability, and cellular infiltration during acute inflammatory reaction induced by carrageenan and concanavalin using chicken skin as test model. It was further evaluated by use of exogenous free copper in experimental model and their subsequent inhibition and amplification by chemical chelators of copper. Present study confirms that free copper fulfilled all the biological requirements for accepting it as an endogenous chemical mediator of inflammation.

Pharmacokinetic and pharmacodynamic evaluation of the novel CCR1 antagonist CCX354 in healthy human subjects: implications for selection of clinical dose.

The safety and pharmacokinetic (PK)/pharmacodynamic (PD) profile of the novel CCR1 antagonist CCX354 was evaluated in double-blind, placebo-controlled, single- and multiple-dose phase I studies (1-300 mg/day oral doses). CCX354 was well tolerated and displayed a linear dose-exposure profile, with half-life approaching 7 h at the 300-mg dose. The extent of CCR1 receptor blockade on blood monocytes, which correlated well with plasma concentrations of the drug, was assessed using fluorescently labeled CCL3 binding in whole blood from phase I subjects. High levels of receptor coverage at the 12-h time point were achieved after a single dose of 100 mg CCX354. Preclinical studies indicate that effective blockade of inflammatory cell infiltration into tissues requires ≥90% CCR1 inhibition on blood leukocytes at all times. The comparison of the properties of CCX354 with those published for other CCR1 antagonists has informed the dose selection for ongoing clinical development of CCX354 in rheumatoid arthritis (RA).

Peritoneal resorption capacity for lipopolysaccharide and interleukin-6 in acute zymosan-induced chemical peritonitis.

AIM: To evaluate peritoneal resorption capacity for lipopolysaccharide (LPS) and interleukin-6 (IL-6) in a model of chemical peritonitis. METHODS: Zymosan peritonitis was induced in anesthetized rats. LPS was injected intraperitoneally to different groups at 4 h (n = 10), 8 h (n = 9), 12 h (n = 9), and 24 h (n = 9) after peritonitis and to a control group (n = 8). Similarly, IL-6 was injected intraperitoneally to different groups at 4 h (n = 9), 8 h (n = 10), 12 h (n = 10), and 24 h (n = 10) after peritonitis, and to a control group (n = 10). Plasma levels of LPS or IL-6 were measured immediately after intraperitoneal injections of LPS or IL-6, respectively, and at 5, 15, 30, 45, and 60 min later. RESULTS: There was no change over time in plasma LPS levels in the groups receiving LPS intraperitoneally (p = 0.4). There was highly significant change over time in the IL-6 level in the studied time periods in the groups receiving IL-6 intraperitoneally (p < 0.0001). There was an increase in the plasma IL-6 level when sampled at 4 h after peritonitis. CONCLUSION: There was a reduction of resorption capacity of inflamed peritoneum for inflammatory mediators in acute chemical peritonitis.

A novel peptide nanomedicine against acute lung injury: GLP-1 in phospholipid micelles.

PURPOSE: Treatment of acute lung injury (ALI) observed in Gram-negative sepsis represents an unmet medical need due to a high mortality rate and lack of effective treatment. Accordingly, we developed and characterized a novel nanomedicine against ALI. We showed that when human glucagon-like peptide 1(7-36) (GLP-1) self-associated with PEGylated phospholipid micelles (SSM), the resulting GLP1-SSM (hydrodynamic size, ~15 nm) exerted effective anti-inflammatory protection against lipopolysaccharide (LPS)-induced ALI in mice. METHODS: GLP1-SSM was prepared by incubating GLP-1 with SSM dispersion in saline and characterized using fluorescence spectroscopy and circular dichroism. Bioactivity was tested by in vitro cAMP induction, while in vivo anti-inflammatory effects were determined by lung neutrophil cell count, myeloperoxidase activity and pro-inflammatory cytokine levels in LPS-induced ALI mice. RESULTS: Amphipathic GLP-1 interacted spontaneously with SSM as indicated by increased α-helicity and fluorescence emission. This association elicited increased bioactivity as determined by in vitro cAMP production. Correspondingly, subcutaneous GLP1-SSM (5-30 nmol/mouse) manifested dose-dependent decrease in lung neutrophil influx, myeloperoxidase activity and interleukin-6 in ALI mice. By contrast, GLP-1 in saline showed no significant anti-inflammatory effects against LPS-induced lung hyper-inflammatory responses. CONCLUSIONS: GLP1-SSM is a promising novel anti-inflammatory nanomedicine against ALI and should be further developed for its transition to clinics.

Sphingosine 1-phosphate (S1P) induces expression of E-selectin and adhesion of monocytes via intracellular signalling pathways in vascular endothelial cells.

Sphingosine 1-phosphate (S1P) - a constitutive component of human plasma - is implicated as a signalling molecule in the regulation of cell adhesion molecules (CAM) in vascular endothelial cells (EC), but the degree of the S1P-induced expression of CAM and the involvement of the S1P(1) receptor are still ambiguous. Here, we report that S1P, when added to vascular EC in the absence of other stimuli, induced a strictly proportional and concentration-dependent expression of E-selectin mRNA, of E-selectin protein and of the number of adhering THP-1 monocytes to EC. Experiments with exogenous [(3)H]S1P showed a multi-exponential influx kinetic of intracellular uptake of [(3)H]S1P up to a steady state level over 2h. This process could be inhibited or enhanced by various synthetic modulators targeting both, S1P(1) receptor-dependent (Akt, ERK1/2) as well as independent DMS-sensitive pathways. The S1P(1) receptor signalling was shown to drive the sphingosine kinase - the rate limiting enzyme for the formation of S1P - to a higher or lower activity. Furthermore, S1P as an intracellular messenger induced the phosphorylation and nuclear translocation of the p65 subunit of NF-kappaB and in turn the expression of E-selectin and monocyte adhesion. Taken together, these results suggest that the physiologically controlled variation in intracellular S1P concentrations may represent a novel not yet known mechanism of fine-tuning the expression of proinflammatory and atherogenic E-selectin cell adhesion molecule by vascular endothelial cells.

Papel de la aldosterona en las alteraciones vasculares funcionales y en el proceso inflamatorio asociados a la hipertensión en ratas / Role of aldosterone in vascular functional alterations and the inflammatory process associated to hypertension in rats

Objetivos: Estudiar la participación de la aldosterona en la disfunción vascular, el proceso inflamatorio y estrés oxidativo vascular asociado a hipertensión. Material y método: Se utilizaron ratas (n = 16) espontáneamente hipertensas (SHR) de 22 semanas de edad. La mitad de las ratas fueron tratadas durante 10 semanas con eplerenona a una dosis de 30 mg/kg/día (E-30). Se utilizaron ratas (n = 8) normotensas (WKY) como grupo de referencia. La presión arterial se midió de manera indirecta en la arteria caudal de la cola de las ratas. Al final del tratamiento las ratas se sacrificaron y se pesaron los corazones. Se evaluó la función endotelial en anillos aórticos en respuesta a la acetilcolina. La expresión del ARN mensajero (ARNm) de las interleucinas 1 β y 6 (IL-1β e IL-6), del factor de necrosis tumoral α (TNF-α), de la enzima óxido nítrico endotelial (eNOS) y de la subunidad p22phox de la enzima NAD(P)H oxidasa se midió en la aorta de las ratas. Resultados: Las SHR presentaron unos valores de presión arterial sistólica mayores (p < 0,05) que las ratas controles WKY (199,8±4,2 frente a 125,3±2,0 mmHg). El tratamiento con eplerenona redujo (p < 0,05) ligeramente las cifras de presión arterial en las ratas hipertensas (E30; 181,0±2,0 mmHg). No hubo diferencias en el peso corporal de las ratas, sin embargo el peso relativo del corazón de las ratas hipertensas era significativamente mayor respecto a las ratas normotensas y se normalizó con el tratamiento con eplerenona. La relajación a acetilcolina estaba significativamente reducida en las ratas SHR así como la expresión vascular de la eNOS. Sin embargo, las ratas hipertensas presentaron una sobreexpresión vascular del ARNm de IL-1β, IL-6, TNF-α y p22phox respecto a las WKY (p < 0,05). El tratamiento con eplerenona normalizó la función endotelial en las ratas hipertensas; aumento la expresión del ARNm de eNOS y redujo la expresión vascular de las citocinas IL-1β, IL-6, TNF-α, así como de la p22phox. Conclusiones: La aldosterona participa en las alteraciones funcionales vasculares en las SHR reduciendo la biodisponibilidad de óxido nítrico, aumentando el estrés oxidativo y el proceso inflamatorio vascular(AU)

Objetives: To study the participation of aldosterone in the vascular dysfunction, inflammatory process and vascular oxidative stress associated to hypertension. Material and methods: Half of the group of 22 week-old spontaneously hypertensive rats (n=16) were treated with eplerenone (E-30; 30 mg/kg/day) for 10 weeks. Normotensive rats (WKY; n = 8) were used as reference group. Systolic arterial pressure (SAP) was measured by the tail-cuff method. Body weight and heart weight were measured at the end of the treatment. Endothelium-dependent relaxations, as well as vascular mRNA expression of interleukin 1 β and 6 (IL-1β and IL-6), tumor necrosis factor alpha (TNF-α), of endothelial nitric oxide synthase (eNOS), NAD(P)H oxidase subunit p22phox were studied in aorta from SHR untreated or treated with eplerenone. Results: SHR showed higher levels of systolic blood pressure (p < 0.05) as compare with control rats (199.8±4.2 vs. 125.33±2.0 mmHg). Although there were no differences in the body weight among the groups, hypertensive rats had a higher relative heart weight compare to normotensive rats and it was normalize with the treatment of eplerenone (p < 0.05). SHR showed higher vascular mRNA expression of IL-1β, IL-6, TNF-α and p22phox compared to WKY (p < 0.05). Treatment with eplerenone slightly reduced (p < 0.05) blood pressure in hypertensive rats (E30; 181.0±2.0 mmHg) and normalized acetylcholine relaxations. Eplerenone enhanced (p < 0.05) eNOS and reduced p22phox, IL-1β, IL-6, TNF-α of aortic mRNA expressions in SHR. Conclusions: In SHR, aldosterone participates in the functional vascular alterations through the diminution of nitric oxide availability and the enhancement of the inflammatory process and the increase of vascular oxidative stress(AU)

Synergistic drug-cytokine induction of hepatocellular death as an in vitro approach for the study of inflammation-associated idiosyncratic drug hepatotoxicity.

Idiosyncratic drug hepatotoxicity represents a major problem in drug development due to inadequacy of current preclinical screening assays, but recently established rodent models utilizing bacterial LPS co-administration to induce an inflammatory background have successfully reproduced idiosyncratic hepatotoxicity signatures for certain drugs. However, the low-throughput nature of these models renders them problematic for employment as preclinical screening assays. Here, we present an analogous, but high-throughput, in vitro approach in which drugs are administered to a variety of cell types (primary human and rat hepatocytes and the human HepG2 cell line) across a landscape of inflammatory contexts containing LPS and cytokines TNF, IFN gamma, IL-1 alpha, and IL-6. Using this assay, we observed drug-cytokine hepatotoxicity synergies for multiple idiosyncratic hepatotoxicants (ranitidine, trovafloxacin, nefazodone, nimesulide, clarithromycin, and telithromycin) but not for their corresponding non-toxic control compounds (famotidine, levofloxacin, buspirone, and aspirin). A larger compendium of drug-cytokine mix hepatotoxicity data demonstrated that hepatotoxicity synergies were largely potentiated by TNF, IL-1 alpha, and LPS within the context of multi-cytokine mixes. Then, we screened 90 drugs for cytokine synergy in human hepatocytes and found that a significantly larger fraction of the idiosyncratic hepatotoxicants (19%) synergized with a single cytokine mix than did the non-hepatotoxic drugs (3%). Finally, we used an information theoretic approach to ascertain especially informative subsets of cytokine treatments for most highly effective construction of regression models for drug- and cytokine mix-induced hepatotoxicities across these cell systems. Our results suggest that this drug-cytokine co-treatment approach could provide a useful preclinical tool for investigating inflammation-associated idiosyncratic drug hepatotoxicity.

Dietary lipids in early development: relevance to obesity, immune and inflammatory disorders.

PURPOSE OF REVIEW: Regardless of social, cultural and behavioural environments, obesity is usually caused by an energy intake above requirements, which is accommodated by the accumulation of triacylglycerols. The composition of dietary fat impacts tissue fatty acids, which are important modulators of multiple cell functions, including differentiation, lipogenesis, lipolysis and the generation of inflammatory mediators. This review focuses on the possible contribution of fatty acids to the link between obesity and inflammation in young children. RECENT FINDINGS: Adipose tissue is a complex organ that functions to regulate fatty acid balance, clearing and releasing fatty acids, and synthesizing protein and signaling molecules that act as local and distant inflammatory mediators. Obesity, even in young children, is associated with increased circulating inflammatory mediators. As a result of changes in dietary fat compositions, infants are exposed to high n-6, saturated and trans fatty acids and low n-3 fatty acids. Saturated and trans fatty acids increase and n-3 fatty acids decrease many metabolic and inflammatory changes that accompany diet-induced triacylglycerol storage. High linoleic acid is associated with increased oxidative stress. SUMMARY: There is a biological reason to consider that dietary fatty acids may contribute to oxidative stress and heightened inflammatory responses in young children.

Controlled release of lipopolysaccharide in the subarachnoid space of rabbits induces chronic vasospasm in the absence of blood.

OBJECTIVE: Leukocyte-endothelial cell interactions appear to play a role in the development of vasospasm after SAH. Using a purely inflammatory protein, LPS, we evaluated the effect of inflammation on the development of chronic vasospasm in the absence of blood and compared it to SAH-induced vasospasm in rabbits. METHODS: Lipopolysaccharide was incorporated into EVAc polymers to produce 20% LPS/EVAc polymers (wt/wt). Rabbits (n = 23) were randomized to 4 experimental groups: (1) empty polymer (n = 6), (2) SAH (n = 5), (3) 0.7 mg/kg polymeric LPS dose (n = 6), and (4) 1.4 mg/kg polymeric LPS dose (n = 6). Blood and polymers were inserted into the cisterna magna. The rabbits were killed 3 days postoperatively, and the basilar arteries were harvested for morphometric analysis. Clinical response and lumen patencies were analyzed using ANOVA and a post hoc Newman-Keuls Multiple Comparisons test. RESULTS: Significant narrowing of the basilar artery was observed by insertion of 20% LPS/EVAc polymers into the subarachnoid space at a polymeric dose of 1.4 mg/kg (actual dose, 66 microg kg(-1) d(-1)) (75.4% +/- 4.2%; P < .01) and by SAH (80.3% +/- 8.1%; P < .01) as compared with the empty polymer group. A trend toward narrowing was observed in the 0.7 mg/kg polymeric LPS dose group (actual dose, 33 microg kg(-1) d(-1)) (85.2% +/- 2.6%; P > .05). Symptoms associated with SAH were noted in 50% of the rabbits in the 0.7 mg/kg LPS group and in 100% of rabbits in the 1.4 mg/kg LPS group. CONCLUSION: Controlled release of LPS into the subarachnoid space of rabbits produced chronic vasospasm in a dose-dependent manner. At a polymeric dose of 1.4 mg/kg, LPS-induced vasospasm was equivalent to that induced by SAH. This suggests that LPS and SAH may induce vasospasm through similar mechanisms and provides further evidence that inflammation plays a central role in the etiology of chronic vasospasm.

The discovery of acylated beta-amino acids as potent and orally bioavailable VLA-4 antagonists.

Acylated beta-amino acids are described as potent, specific and orally bioavailable antagonists of VLA-4. The initial lead was identified from a combinatorial library. Subsequent optimization using a traditional medicinal chemistry approach led to significant improvement in potency (up to 8-fold) while maintaining good pharmacokinetic properties.

Transfer of endogenous pyrogens across artificial membranes?

Synthetic high-flux dialyzer membranes used in continuous veno-venous hemofiltration are permeable to middle molecular size endogenous pyrogens, the pro-inflammatory cytokines IL-1 beta and TNF-alpha. The quantities removed by sieving are, however, negligible in vitro as well as in vivo. Adsorption of cytokines to the membrane polymer is the major mechanism of pyrogen removal. Adsorption seems to be semispecific for pro-inflammatory cytokines because levels of anti-inflammatory mediators were not changed or even increased during CVVH. Thus, CVVH may change cytokine profiles in septic patients supporting the predominance of anti-inflammatory over pro-inflammatory activity in plasma. It remains to be demonstrated whether modifications of extracorporeal blood purification systems (high-volume CVVH, plasma separation + adsorption) are able to amplify the change in cytokine profiles and whether this change influences outcome of septic patients.

Histamine release from bronchoalveolar lavage cells from asthmatic subjects after allergen challenge and relationship to the late asthmatic response.

BACKGROUND: Metachromatic cells obtained from asthmatic subjects demonstrate increased spontaneous and stimulated histamine release in vitro. Their ability to synthesize and store proinflammatory cytokines has focused renewed interest on their role in asthma. OBJECTIVE: The late asthmatic response provides a useful model of clinical asthma. The aim of the study was to examine metachromatic cell derived mediators and histamine releasability in vitro after in vivo allergen exposure in atopic subjects with and without asthma and relate them to the type of physiological response observed. METHODS: Bronchoalveolar lavage (BAL) cells were obtained 4 h after challenge from asthmatics exhibiting a single early response (EAR, n = 5), a dual response (LAR, n = 7), unchallenged (basal, n = 5), atopic non-asthmatic (ANA, n = 6) and non-atopic non-asthmatics (normal, n = 5). BAL histamine and tryptase concentrations and in vitro histamine release (HR) after stimulation with anti-IgE, allergen, A23187, conconavalin A and substance P were compared. RESULTS: Metachromatic cell numbers were lower in normal controls compared with all asthmatic groups and in LAR compared with EAR. Metachromatic cell derived mediators were higher in asthmatic compared with normal subjects. Spontaneous HR in LAR (20.5 +/- 5.0%) was lower than EAR (29.5 +/- 3.9%) and ANA (30.2 +/- 1.4%) (P < 0.05). No differences were seen in stimulated HR between EAR and LAR. HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). After stimulation with ionophore A23187 (1 microM), release was greater in LAR compared with basal (P < 0.05) and no different at 5 microM. All subject groups responded to substance P (SP) but was significantly more in the asthmatic subjects compared to normal controls (P < 0.05). Allergen challenge did not modify the response of asthmatic subjects to SP. CONCLUSION: Functional differences in metachromatic cell reactivity are present in atopic subjects 4h after in vivo allergen exposure which relate to the physiological response observed after this time and suggest that there is ongoing metachromatic cell degranulation subjects who subsequently develop LAR.

Mechanisms of transit of lipid mediators of inflammation and bacterial peptides across intestinal epithelia.

The transit of two lipid mediators of inflammation, leukotriene B4 (LTB4) and prostaglandin E2 (PGE2), and a formylated peptide produced by intestinal bacteria, N-formylmethionylleucylphenylalanine (FMLP), across Caco-2 cell monolayers was characterized and compared with the transit of mannitol, a hexose known to cross epithelial monolayers by paracellular pathways. The permeability of less mature low-resistance ( < 200 ohm.cm2) monolayers to all four test compounds was similar, but as monolayers matured and the transmonolayer resistance increased, the transit of LTB4, PGE2, FMLP, and mannitol decreased to different degrees, resulting in a selectivity of permeability to the four test compounds in the order LTB4 > PGE2 > mannitol > FMLP. The transit of all four test compounds across Caco-2 cell monolayers was bidirectional, nonsaturable, and energy independent. A small portion of the added LTB4 was incorporated into the cells, whereas the other three compounds were not. Thus the transit of PGE2, mannitol, and FMLP across Caco-2 monolayers appears to be solely by the paracellular pathway, whereas the transit of LTB4 also involves the paracellular pathway but may also involve diffusion through the cell membrane and around tight junctions.