Effects of Caffeoylquinic Acid Derivatives and C-Flavonoid from Lychnophora ericoides on in vitro Inflammatory Mediator Production

In this study we aimed at evaluating the effect of the major polar constituents of the medicinal plant Lychnophora ericoides on the production of inflammatory mediators produced by LPS-stimulated U-937 cells. The 6,8-di-C-beta-glucosylapigenin (vicenin-2) presented no effect on tumor necrosis factor (TNF)-alpha production, but inhibited, in a dose-dependent manner, the production of prostaglandin (PG) E(2) without altering the expression of cyclooxygenase (COX) -2 protein. 3,5-Dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid, at lower concentrations, had small but significant effects on reducing PG E, levels; at higher doses these compounds stimulated PGE(2) and also TNF-alpha production by the cells. All the caffeoylquinic acid derivatives, in a dose-dependent fashion, were able to inhibit monocyte chemoattractant protein-3 synthesis/release, with 4,5-DCQ being the most potent at the highest tested concentration. These results add important information on the effects of plant natural polyphenols, namely vicenin-2 and caffeoylquinic acid derivatives, on the production of inflammatory mediators by cultured cells.

Antidepressant-like effects of N-acetyl-L-cysteine in rats

Oxidative stress disturbances have been reported in depressed patients and in animals submitted to stress. Recent evidence suggests that antidepressants may have antioxidant properties. However, the therapeutic potential of antioxidants as antidepressant drugs has not been systematically investigated. Therefore, this study tested the hypothesis that N-acetyl-L-cysteine (NAC), a cysteine prodrug with powerful antioxidant activity, would possess anti depressant-like properties in the forced swimming test. Male Wistar rats were subjected to 15 min of forced swimming and immediately afterward, 5, and 23 h later received intraperitoneal injections of NAC (5, 15, 50, 150, and 250 mg/kg), imipramine, 0 5 mg/kg) or vehicle. One hour later they were submitted to the 5 min test swimming session, where immobility time was recorded. Independent groups of animals received the same treatments and their exploratory activity was measured in an open arena for 5 min. NAC (at the doses of 15, 50, and 150 mg/kg) and imipramine induced a significant decrease in immobility time without changing exploratory behavior measured in an open arena. These results suggest that antioxidants such as NAC may have antidepressant effects. Behavioural Pharmacology (C) 19:747-750 2008 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Non-coding transcript in T cells (NTT): Antisense transcript activates PKR and NF-kappa B in human lymphocytes

T cell activation is a complex process involving many steps and the role played by the non-protein-coding RNAs (ncRNAs) in this phenomenon is still unclear. The non-coding T cells transcript (NTT) is differentially expressed during human T cells activation, but its function is unknown. Here, we detected a 426 m NTT transcript by RT-PCR using RNA of human lymphocytes activated with a synthetic peptide of HIV-1. After cloning, the sense and antisense 426 nt NTT transcripts were obtained by in vitro transcription and were sequenced. We found that both transcripts are highly structured and are able to activate PKR. A striking observation was that the antisense 426 nt NTT transcript is significantly more effective in activating PKR than the corresponding sense transcript. The transcription factor NF-kappa B is activated by PKR through phosphorylation and subsequent degradation of its inhibitor I-kappa B beta. We also found that the antisense 426 nt NTT transcript induces more efficiently the degradation Of I-kappa B beta than the sense transcript. Thus, this study suggests that the role played by NTT in the activation of lymphocytes can be mediated by PKR through NF-kappa B activation. However, the physiological significance of the activity of the antisense 426 nt NTT transcript remains unknown. (c) 2007 Elsevier Inc. All rights reserved.

Prenatal lipopolysaccharide reduces motor activity after an immune challenge in adult male offspring

Prenatal lipopolysaccharide (LPS) exposure causes reproductive, behavioral and neurochemical injuries in both the mother and pups. Previous investigations by our group showed that prenatal LPS administration (100 mu g/kg, i.p.) on gestational day 9.5 impaired the male offspring`s social behavior in infancy and adulthood. In the present study, we investigated whether these social behavioral changes were associated with motor activity impairment. Male rat pups treated prenatally with LPS or not were tested for reflexological development and open field general activity during infancy. In adulthood, animals were tested for open field general activity, haloperidol-induced catalepsy and apomorphine-induced stereotypy; striatal dopamine levels and turnover were also measured. Moreover, LPS-treated or untreated control pups were challenged with LPS in adulthood and observed for general activity in the open field. In relation to the control group, the motor behavior of prenatally treated male pups was unaffected at basal levels, both in infancy and in adulthood, but decreased general activity was observed in adulthood after an immune challenge. Also, striatal dopamine and metabolite levels were decreased in adulthood. In conclusion, prenatal LPS exposure disrupted the dopaminergic system involved with motor function, but this neurochemical effect was not accompanied by behavioral impairment, probably due to adaptive plasticity processes. Notwithstanding, behavioral impairment was revealed when animals were challenged with LPS, resulting in enhanced sickness behavior. (C) 2010 Elsevier B.V. All rights reserved.

Prenatal Lipopolysaccharide Reduces Social Behavior in Male Offspring

Objective: This study investigated the relationship between maternal sickness behavior during pregnancy and offspring development and behavior. Methods: Pregnant Wistar rats were administered with lipopolysaccharide (LPS, 100 mu g/kg, i.p.) on gestation day (GD) 9.5. Dams` sickness behavior was analyzed, and at birth, offspring number and weight were evaluated. Male offspring was evaluated through physical development, play behavior, adult social interaction, plus maze studies and morphological analysis of the brain. Results: Results, with respect to the control group, showed that: (1) LPS decreased general activity, food intake, and weight gain in dams, but no pyrexia was observed following treatment; (2) LPS reduced litter size, but no alterations in physical development were observed; (3) LPS reduced play behavior parameters in baby rats; (4) LPS decreased adult social interaction; (5) no alterations were observed between groups on plus maze studies; (6) no differences were observed between groups on morphological analyses of the brain. Conclusion: These data reveal that LPS administered on GD 9.5 impaired male offspring`s social behavior in infancy and adulthood. These results may be related to an alteration in motivational states or/and increased anxiety. Copyright (C) 2010 S. Karger AG, Basel

Prenatal Lipopolysaccharide Exposure Affects Maternal Behavior and Male Offspring Sexual Behavior in Adulthood

Objective: This study investigates the effects of prenatal lipopolysaccharide (LPS) exposure on the maternal behavior of pregnant rats and the physical development and sexual behavior of their male offspring in adulthood. Methods: For two experiments, pregnant rats were injected with LPS (250 mu g/kg, i.p.) on gestation day (GD) 21. In the first experiment, the maternal behavior (postnatal day, PND, 6) and the dam`s open-field general activity (PND7) were evaluated. In the second experiment, the maternal pre- and postnatal parameters, the pup`s development, the offspring`s sexual behavior in adulthood, and the pup`s organ weights were assessed. Results: Compared to the control group, the LPS-treated dams presented reduced maternal behavior, decreased general activity, a smaller body weight difference between GD21 and PND1, a greater number of perinatal deaths, and smaller litters. For the male pups, LPS treatment resulted in a decreased body weight on PND2, whereas the anogenital distance and the day of testis descent were not modified. The male sexual behavior was impaired by prenatal LPS. Particularly the number of ejaculating animals was reduced. The testis weight was also lower in the prenatally LPS-treated rats than in the control rats. Conclusion: We propose that prenatal LPS exposure on GD21 acts as an imprinting factor that interferes with the programming of brain sexual determination in offspring. Copyright (C) 2009 S. Karger AG, Basel

Sickness and Aggressive Behavior in Dominant and Subordinate Mice

Sick animals show a set of organized behavioral changes (sickness behavior), which is the result of a motivational re-organization of the behavior as a whole. Sickness behavior display can be influenced by the social context. In this work, we sought to investigate the regulation of sickness behavior within a pair of mice in the presence of an intruder mouse. Dominant and subordinate mice were treated with the bacterial endotoxin lipopolysaccharide (LPS) and were challenged with the presence of an intruder mouse. LPS effects depended on ranking and social context. Even though dominant mice displayed more agonistic interaction towards the intruder, subordinate mice displayed agonistic behavior towards the intruder when their dominant companion was treated with LPS. The results show that, not only sickness behavior is differentially expressed among different social ranks, but also that sickness behavior is related to different reactions among surrounding animals. These data are relevant for a biological approach to the relation between sickness behavior and social behavior.

Behavior: A Relevant Tool for Brain-immune System Interaction Studies

Neuroimmunomodulation describes the field focused on understanding the mechanisms by which the central nervous system interacts with the immune system, potentially leading to changes in animal behavior. Nonetheless, not many articles dealing with neuroimmunomodulation employ behavior as an analytical endpoint. Even fewer papers deal with social status as a possible modifier of neuroimmune phenomena. In the described sets of experiments, we tackle both, using a paradigm of social dominance and subordination. We first review data on the effects of different ranks within a stable hierarchical relationship. Submissive mice in this condition display more anxiety-like behaviors, have decreased innate immunity, and show a decreased resistance to implantation and development of melanoma metastases in their lungs. This suggests that even in a stable, social, hierarchical rank, submissive animals may be subjected to higher levels of stress, with putative biological relevance to host susceptibility to disease. Second, we review data on how dominant and submissive mice respond differentially to lipopolysaccharide (LPS), employing a motivational perspective to sickness behavior. Dominant animals display decreased number and frequency in several aspects of behavior, particularly agonistic social interaction, that is, directed toward the submissive cage mate. This was not observed in submissive mice that maintained the required behavior expected by its dominant mate. Expression of sickness behavior relies on motivational reorganization of priorities, which are different along different social ranks, leading to diverse outcomes. We suggest that in vitro assessment of neuroimmune phenomena can only be understood based on the behavioral context in which they occur.

Single early prenatal lipopolysaccharide exposure prevents subsequent airway inflammation response in an experimental model of asthma

Aims: There has been emerging interest in the prenatal determinants of respiratory disease. In utero factors have been reported to play a role in airway development, inflammation, and remodeling. Specifically, prenatal exposure to endotoxins might regulate tolerance to allergens later in life. The present study investigated whether prenatal lipopolysaccharide (LPS) administration alters subsequent offspring allergen-induced inflammatory response in adult rats. Main methods: Pregnant Wistar rats were treated with LPS (100 mu g/kg, i.p.) on gestation day 9.5 and their ovariectomized female offspring were sensitized and challenged with OVA later in adulthood. The bronchoalveolar lavage (BAL) fluid, peripheral blood, bone marrow leukocytes and passive cutaneous anaphylaxis were evaluated in these 75-day-old pups. Key findings: OVA sensitized pups of NaCl treated rats showed an increase of leucocytes in BAL after OVA challenge. This increase was attenuated, when mothers were exposed to a single LPS injection early in pregnancy. Thus, LPS prenatal treatment resulted in (1) lower increased total and differential (macrophages, neutrophils, eosinophils and lymphocytes) BAL cellularity count; (2) increased number of total, mononuclear and polymorphonuclear cells in the peripheral blood; and (3) no differences in bone marrow cellularity or passive cutaneous anaphylaxis. Significance: In conclusion, female pups treated prenatally with LPS presented an attenuated response to experimentally-induced asthma. We observed reduced immune cell migration from peripheral blood to the lungs, with no effect on the production of bone marrow cells or antibodies. It was suggested that inflammatory events such as exposure to LPS in early fetal life can attenuate allergic inflammation in the lung, which is a common symptom in asthma. (C) 2011 Elsevier Inc. All rights reserved.

Release of cytokines by stimulated peripheral blood mononuclear cells in chronic periodontitis

Objective: The emergence of periodontal medicine increased interest in defining the behaviour of peripheral blood cells in periodontitis subjects in comparison with healthy group. The aim of this study was to evaluate the levels of interleukin (IL)-8, tumour necrosis factor-alpha (TNF-alpha), IL-6 and IL-10 released by Escherichia coli lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMC) obtained from the peripheral blood of chronic periodontitis subjects. Design: PBMC samples were isolated from 19 systemically healthy donors, divided into generalized chronic periodontitis (n = 10) and healthy (n = 9) subjects. Cells were incubated for 24-48 h in 500 mu L wells containing RPM! 1640 and stimulated with 1.0 ng/mL of E. coli LPS. Supernatants were used to quantify the amounts of IL-8, TNF-alpha, IL-6 and IL-10 released using enzyme-linked immunosorbent assay (ELISA). Results: PBMC cells from periodontitis subjects released higher levels of TNF-alpha and IL-6 than those from healthy subjects (P < 0.05). Conversely, the supernatants of the stimulated PBMC cells obtained from healthy subjects presented higher amounts of IL-8 than those from periodontitis (P < 0.05). No differences were observed in the levels of IL-10 (P > 0.05) between groups. Conclusion: In conclusion, the results of the present study showed that E. coli LPS-stimulated PBMC from subjects with periodontitis present a different pattern of cytokine release when compared to PBMC from healthy subjects. This phenomenon could have implications locally, in periodontitis, as well as in systemic diseases. (C) 2010 Elsevier Ltd. All rights reserved.

Alteration of Ca(2+)-ATPase activity in the homogenate, plasma membrane and microsomes of the salivary glands of streptozotocin-induced diabetic rats

Diabetes has been implicated in the dryness of the mouth, loss of taste sensation, sialosis, and other disorders of the oral cavity, by impairment of the salivary glands. The aim of the present study was to examine the plasma membrane, microsomal, and homogenate Ca(2+)-ATPase activity in the rat submandibular and parotid salivary glands of streptozotocin-induced diabetes. We have also examined the influence of the acidosis state oil this parameter. Diabetes was induced by an intraperitoneal injection of streptozotocin and acidosis was induced by daily injection of NH(4)Cl. At 15 and 30 days after diabetes induction, the animals were euthanized and the submandibular and parotid salivary glands were removed and analyzed. Ca(2+)-ATPase (total, independent, and dependent) was determined in the homo-enate, microsomal, and plasma membranes of the salivary glands of diabetic and control rats. Calcium concentration was also determined in the glands and showed to be hi-her in the diabetic animals. Ca(2+)-ATPase activity was found to be reduced in all cell fractions studied in the diabetic animals compared with control. Similar results were obtained for the submandibular salivary glands of acidotic animals; however in the parotid salivary glands it was found an increase in the enzyme activity. Copyright (c) 2009 John Wiley & Sons, Ltd.

Effect of lipopolysaccharide from periodontal pathogens on the production of tissue plasminogen activator and plasminogen activator inhibitor 2 by human gingival fibroblasts

Both tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 2 (PAI-2) are important proteolysis factors present in inflamed human periodontal tissues. The aim of the present study was to investigate the effect of lipopolysaccharide (LPS) on the synthesis: of t-PA and PAI-2 by human gingival fibroblasts (HGF). LPS from different periodontal pathogens including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum were extracted by the hot phenol water method. The levels of t-PA and PAI-2 secreted into the cell culture media were measured by enzyme-linked immunosorbent assays (ELISA). The mRNA for t-PA and PAI-2 were measured by RT-PCR. The results showed t-PA synthesis was increased in response to all types of LPS studied and PAI-2 level was increased by LPS from A. actinomycetemcomitans and F. nucleatum, but not P. gingivalis. When comparing the effects of LPS from non-periodontal bacteria (Escherichia coli and Salmonella enteritidis) with the LPS from periodontal pathogens, we found that the ratio of t-PA to PAI-2 was greater following exposure of the cells to LPS from periodontal pathogens. The highest ratio of t-PA to PAI-2 was found in those cells exposed to LPS from P. gingivalis. These results indicate that LPS derived from periodontal pathogens may cause unbalanced regulation of plasminogen activator and plasminogen activator inhibitor by HGF and such an effect may, in part, contribute to the destruction of periodontal connective tissue through dysregulated pericellular proteolysis.

Differential Production of Macrophage Inflammatory Protein-1 alpha, Stromal-Derived Factor-1, and IL-6 by Human Cultured Periodontal Ligament and Gingival Fibroblasts Challenged With Lipopolysaccharide From P. gingivalis

Background: Fibroblasts are considered important cells in periodontitis. When challenged by different agents, they respond through the release of cytokines that participate in the inflammatory process. The aim of this study is to evaluate and compare the expression and production of macrophage inflammatory protein (MIP)-1 alpha, stromal-derived factor (SDF)-1, and interleukin (IL)-6 by human cultured periodontal ligament and gingival fibroblasts challenged with lipopolysaccharide (LPS) from Porphyromonas gingivalis. Methods: Fibroblasts were cultured from biopsies of gingival tissue and periodontal ligament of the same donors and used on the fourth passage. After confluence in 24-well plates, the culture medium alone (control) or with 0.1 to 10 mu g/ml of LPS from P. gingivalis was added to the wells, and after 1, 6, and 24 hours, the supernatant and the cells were collected and analyzed by enzyme-linked immunosorbent assay and real-time polymerase chain reaction, respectively. Results: MIP-1 alpha, SDF-1, and IL-6 protein production was significantly greater in gingival fibroblasts compared to periodontal ligament fibroblasts. IL-6 was upregulated in a time-dependent manner, mainly in gingival fibroblasts (P<0.05), which secreted more MIP-1 alpha in the lowest concentration of LPS used (0.1 mu g/ml). In contrast, a basal production of SDF-1 that was inhibited with the increase of LPS concentration was detected, especially after 24 hours (P<0.05). Conclusion: The distinct ability of the gingival and periodontal ligament fibroblasts to secrete MIP-1 alpha, SDF-1, and IL-6 emphasizes that these cells may differently contribute to the balance of cytokines in the LPS-challenged periodontium. J Periodontol 2010;81:310-317.

Osteointegration of Autogenous Bone Graft Associated With Osteoblastic Cells Under Treatment With Caffeine

Purpose: The present study investigated osteointegration of autogenous bone (AB) from calvaria graft associated with osteoblastic cells (OC) in bone defects in rats subjected to daily administration of caffeine. Materials and Methods: Male rats received daily intraperitoneal injection of 1.5% caffeine (0.2 mL/100 g body weight) or saline solution for 30 days. Then they were anesthetized, submitted to the extraction of the upper right incisor, and implanted with AB only and AB + OC. The animals were killed on 7th, 21st, and 42nd days after surgery, and their maxilla were processed for obtaining semiserial sections (5 mu m) stained with hematoxylin and eosin. Through image analysis system, the bone volume and the quality of graft in adjacent areas were estimated. Results: The results showed that in caffeine treatment, the AB + OC graft showed no foreign body and acute inflammatory reactions inside the defect when compared to AB. The histometric results revealed that the association AB + OC produced significant increase (10%-15%) in bone volume in later experimental period (42 days) when compared with saline solution group (P <= 0.01). Conclusions: It was concluded that the association of AB from calvaria + OC demonstrated progressive osteointegration and accelerated the repair of bone defects in animals treated with daily caffeine. (Implant Dent 2011;20:369-373)

Reduced stress fever is accompanied by increased glucocorticoids and reduced PGE(2) in adult rats exposed to endotoxin as neonates

Immune challenges during neonatal period may permanently program immune responses later in life, including endotoxin fever. We tested the hypothesis that neonatal endotoxin exposure affects stress fever in adult rats. In control rats (treated with saline as neonates; nSal) body temperature peaked similar to 1.5 degrees C during open-field stress, whereas in rats exposed to endotoxin (lipopolysaccharide, LPS) as neonates (nLPS) stress fever was significantly attenuated. Following stress, plasma corticosterone levels significantly increased from 74.29 +/- 7.05 ng ml(-1) to 226.29 +/- 9.87 ng ml(-1) in nSal rats, and from 83.43 +/- 10.31 ng ml(-1) to 324.7 +/- 36.87 ng ml(-1) in nLPS rats. Animals treated with LPS as neonates and adrenalectomized one week before experimentation no longer displayed the attenuated febrile response to stress. This attenuated stress fever caused by an increased corticosterone secretion is likely to be linked to an inhibitory effect of glucocorticoids on cyclooxygenase activity/PGE(2) production in preoptic/anteroventral third ventricular region (AV3V) since stress failed to cause a significant increase in PGE(2) in nLPS rats, and this effect was reverted by adrenalectomy. Altogether, the present results indicate that endogenous glucocorticoids are key modulators of the attenuated stress fever in adult rats treated with LPS as neonates, and they act downregulating PGE(2) production in AV3V. Moreover, our findings also support the notion that neonatal immune stimulus affects programming of stress responses during adulthood, despite the fact that inflammation and stress are two distinct processes mediated largely by different neurobiological mechanisms. (C) 2010 Elsevier B.V. All rights reserved.