Systemic Metabolic Signatures of Oral Diseases.

Systemic metabolic signatures of oral diseases have been rarely investigated, and prospective studies do not exist. We analyzed whether signs of current or past infectious/inflammatory oral diseases are associated with circulating metabolites. Two study populations were included: the population-based Health-2000 (n = 6,229) and Parogene (n = 452), a cohort of patients with an indication to coronary angiography. Health-2000 participants (n = 4,116) provided follow-up serum samples 11 y after the baseline. Serum concentrations of 157 metabolites were determined with a nuclear magnetic resonance spectroscopy-based method. The associations between oral parameters and metabolite concentrations were analyzed using linear regression models adjusted for age, sex, number of teeth, smoking, presence of diabetes, and education (in Health-2000 only). The number of decayed teeth presented positive associations with low-density lipoprotein diameter and the concentrations of pyruvate and citrate. Negative associations were found between caries and the unsaturation degree of fatty acids (FA) and relative proportions of docosahexaenoic and omega-3 FAs. The number of root canal fillings was positively associated with very low-density lipoprotein parameters, such as diameter, cholesterol, triglycerides, and number of particles. Deepened periodontal pockets were positively associated with concentrations of cholesterol, triglycerides, pyruvate, leucine, valine, phenylalanine, and glycoprotein acetyls and negatively associated with high-density lipoprotein (HDL) diameter, FA unsaturation degree, and relative proportions of omega-6 and polyunsaturated FAs. Bleeding on probing (BOP) was associated with increased concentrations of triglycerides and glycoprotein acetyls, as well as decreased proportions of omega-3 and omega-6 FAs. Caries at baseline predicted alterations in apolipoprotein B-containing lipoproteins and HDL-related metabolites in the follow-up, and both caries and BOP were associated with changes in HDL-related metabolites and omega-3 FAs in the follow-up. Signs of current or past infectious/inflammatory oral diseases, especially periodontitis, were associated with metabolic profiles typical for inflammation. Oral diseases may represent a modifiable risk factor for systemic chronic inflammation and thus cardiometabolic disorders.

Phenotype Harmonization in the GLIDE2 Oral Health Genomics Consortium.

Genetic risk factors play important roles in the etiology of oral, dental, and craniofacial diseases. Identifying the relevant risk loci and understanding their molecular biology could highlight new prevention and management avenues. Our current understanding of oral health genomics suggests that dental caries and periodontitis are polygenic diseases, and very large sample sizes and informative phenotypic measures are required to discover signals and adequately map associations across the human genome. In this article, we introduce the second wave of the Gene-Lifestyle Interactions and Dental Endpoints consortium (GLIDE2) and discuss relevant data analytics challenges, opportunities, and applications. In this phase, the consortium comprises a diverse, multiethnic sample of over 700,000 participants from 21 studies contributing clinical data on dental caries experience and periodontitis. We outline the methodological challenges of combining data from heterogeneous populations, as well as the data reduction problem in resolving detailed clinical examination records into tractable phenotypes, and describe a strategy that addresses this. Specifically, we propose a 3-tiered phenotyping approach aimed at leveraging both the large sample size in the consortium and the detailed clinical information available in some studies, wherein binary, severity-encompassing, and "precision," data-driven clinical traits are employed. As an illustration of the use of data-driven traits across multiple cohorts, we present an application of dental caries experience data harmonization in 8 participating studies (N = 55,143) using previously developed permanent dentition tooth surface-level dental caries pattern traits. We demonstrate that these clinical patterns are transferable across multiple cohorts, have similar relative contributions within each study, and thus are prime targets for genetic interrogation in the expanded and diverse multiethnic sample of GLIDE2. We anticipate that results from GLIDE2 will decisively advance the knowledge base of mechanisms at play in oral, dental, and craniofacial health and disease and further catalyze international collaboration and data and resource sharing in genomics research.

Prediction of neo-adjuvant chemotherapy response in bladder cancer: the impact of clinical parameters and routine biomarkers.

PURPOSE: To investigate the role of clinical parameters and immunohistochemical (IHC) biomarkers in their feasibility to predict the effect of neo-adjuvant chemotherapy (NAC) in patients with muscle-invasive urothelial bladder cancer (MIBC). MATERIALS AND METHODS: The first 76 consecutive patients with MIBC treated with NAC and radical cystectomy in two University hospitals in Finland between 2008 and 2013 were chosen for this study. After excluding patients with non-urothelial cancer, less than two cycles of chemotherapy, no tissue material for IHC analysis or non-muscle-invasive bladder cancer in re-review, 59 patients were included in the final analysis. A tissue microarray block was constructed from the transurethral resection samples and IHC stainings of Ki-67, p53, Her-2 and EGFR were made. The correlations between histological features in transurethral resection samples and immune-histochemical stainings were calculated. The associations of clinicopathological parameters and IHC stainings with NAC response were evaluated. Factors affecting survival were estimated. RESULTS: The complete response rate after NAC was 44%. A higher number of chemotherapy cycles was associated with better response to neo-adjuvant chemotherapy. No response to neo-adjuvant chemotherapy and female gender was associated with decreased cancer-specific survival. The IHC stainings used failed to show an association with neo-adjuvant chemotherapy response and overall or cancer specific survival. CONCLUSIONS: Patients who do not respond to neo-adjuvant chemotherapy do significantly worse than responders. This study could not find clinical tools to distinguish responders from non-responders. Further studies preferably with larger cohorts addressing this issue are warranted to improve the selection of patients for neo-adjuvant chemotherapy.

Carotid artery calcification in panoramic radiographs associates with oral infections and mortality.

AIM: To study the prevalence of carotid artery calcification (CAC) in relation to apical and marginal periodontitis, subgingival dysbiotic bacterial species and serum and saliva immune responses against them. In addition, the aim was to analyse the association of CAC with angiographically verified coronary artery disease (CAD) and mortality. METHODOLOGY: In the present random Parogene cohort, the patients had an indication for coronary angiography. Apical and marginal periodontitis were diagnosed during clinical and radiographic oral examinations, and CAC on panoramic radiographs (n = 492). Presence and severity of CAD were registered from angiography. Subgingival dysbiotic bacterial species were quantitated using checkerboard DNA-DNA-hybridization, and serum and saliva antibody levels were determined by immunoassays. The cohort was followed-up for 10 years or until death (median 9.9, range 0.21-10.4) via linkage to the national death register. The statistical models were adjusted for age, gender, smoking, hypertension, diabetes and dyslipidemia. RESULTS: A total of 102 (20.7%) patients had detectable CAC, which was moderate in 81 (16.4%) and severe in 21 (4.3%). CAC was associated (OR, 95% CI) with severe apical periodontitis (2.25, 1.15-4.41), root canal fillings (1.15, 1.04-1.26), alveolar bone loss (2.66, 1.21-5.84), severe periodontal inflammation (2.23, 1.11-4.47), high level of gram-negative subgingival species (2.73, 1.34-5.50), saliva IgG against dysbiotic species (1.05, 1.01-1.10/unit) and severe (2.58, 1.36-4.90) and chronic (2.13, 1.15-3.93) CAD. A total of 105 (20.7%) patients died during the follow-up and 53 (10.4%) deaths were because of cardiovascular diseases (CVD). Severe CAC predicted worse survival with HRs (95% CI) of 3.08 (1.58-6.06) for all-cause and 3.43 (1.42-8.25) for CVD death. CONCLUSIONS: CAC on panoramic tomography was associated with (i) apical and marginal periodontitis and dysbiotic bacterial species giving rise to an immunological response, and with (ii) severe, chronic CAD and increased mortality. The results further emphasize the role of oral infections in CAD and the importance of referring a patient with CAC for a cardiovascular evaluation.

Association between dental factors and mortality.

AIM: To study whether oral parameters such as endodontic infections, root canal fillings, number of teeth or wearing removable dentures at baseline are associated with cardiovascular- and all-cause mortality in a follow-up of approximately 8 years. METHODOLOGY: The Finnish Parogene cohort consists of 508 Finnish adults (mean age 63.3 years, SD 9.1) with cardiac symptoms, all of whom had undergone coronary angiography for accurate baseline coronary status. Extensive clinical and radiographic oral examinations were performed, and additional data were acquired from medical records and questionnaires. Root canal fillings and endodontic lesions, as well as their co-occurrence, were determined from panoramic radiographs. The mortality data were assessed via record linkage with the Finnish Causes of Death register (mean follow-up time 7.81 years, SD 1.45 years). A total of n = 471 dentate patients were included in the statistical analyses. RESULTS: A total of n = 69 deaths were recorded, of which n = 41 were due to cardiovascular diseases (CVDs, ICD-10 I00-I99). The deceased had fewer root canal fillings (mean 1.57; SD 1.64 vs. mean 2.30; SD 2.34, P = 0.03) than the survivors. The number of missing teeth was associated with smoking, occluded coronary arteries and diabetes. Cox regression with Firth's penalized maximum-likelihood method using age as timescale revealed an inverse association (HR; 95%CI) between mortality and number of teeth (all-cause 0.91; 0.86-0.96, CVD mortality 0.89; 0.83-0.96), use of removable dentures (all-cause 0.24; 0.09-0.62, CVD mortality 0.20; 0.06-0.72), root canal fillings (all-cause 0.82; 0.70-0.94, CVD mortality 0.79; 0.63-0.96) and having root canal fillings in all teeth with apical rarefactions (all-cause 0.27; 0.06-0.79, CVD mortality 0.09; 0.01-0.63), when gender, smoking, occluded coronary arteries, periodontal inflammatory burden index and the number of teeth were adjusted for. CONCLUSIONS: The number of missing teeth appeared to be the strongest predictor of mortality in this study, whereas endodontic infections per se had no independent association. Nevertheless, signs of professional intervention in these problems, such as root canal fillings and removable dentures, appeared to be associated with improved survival, which might partly be explained by the utilization of healthcare services.

Childhood Oral Infections Associate with Adulthood Metabolic Syndrome: A Longitudinal Cohort Study.

Chronic oral infection/inflammation is cross-sectionally associated with metabolic syndrome (MetS) in adults, but there are few longitudinal studies and studies on childhood oral infections and adult MetS risk. We investigated whether childhood clinical parameters indicative of oral infection/inflammation were associated with adulthood MetS and its components. A total of 755 children aged 6, 9, and 12 y underwent a clinical oral examination in 1980 as part of the Cardiovascular Risk in Young Finns Study. Oral health measures included bleeding on probing (BOP), periodontal probing pocket depth, caries, fillings, and visible plaque. Metabolic parameters were determined at baseline and during follow-up. MetS was diagnosed (n = 588, 77.9%) in the adulthood at 21 y (in 2001), 27 y (in 2007), and 31 y (in 2011) after the oral assessment, when the participants were 27 to 43 y old. Regression analyses were adjusted for childhood age, sex, body mass index, and family income, as well as adulthood smoking and education level. In adulthood, MetS was diagnosed in 11.9% (2001), 18.7% (2007), and 20.7% (2011) of participants at the 3 follow-ups. Childhood caries and fillings were associated with increased risk of adult MetS (risk ratio [95% CI], 1.25 [0.90 to 2.45] and 1.27 [1.02 to 1.99]) and with increased systolic blood pressure (1.78 [1.01 to 4.26] and 2.48 [1.11 to 4.12]) and waist circumference (2.25 [1.02 to 4.99] and 1.56 [1.01 to 3.25]), whereas BOP and visible plaque were associated with plasma glucose (1.97 [1.08 to 3.60] and 1.88 [1.00 to 3.53]). Severity of BOP (P = 0.015) and caries (P = 0.005) and teeth with plaque (P = 0.027) were associated with number of MetS components. No such trends were seen with probing pocket depth. Childhood oral infection/inflammation was associated with adverse metabolic parameters and MetS in adulthood.

Lymph node imaging in bladder cancer.

Staging of muscle invasive bladder cancer (MIBC) remains a challenge. It is generally acknowledged that the most commonly used imaging techniques have a trend either to upstage or downstage the disease. The aim of this review article is to evaluate the currently available scientific evidence for the use of imaging modalities in preoperative bladder cancer staging with special attention to detection of lymph node metastasis (LNM). A non-systematic literature search utilizing PUBMED database with terms MIBC and LN and MRI or PET or CT was performed with the search limited to articles published between 2010-2015. Magnetic resonance imaging (MRI) has shown potential for local tumor detection and staging in multiple studies, but the accuracy for LNM detection remains disappointingly low. The LN staging accuracy is improved with the use of ultra-small super-paramagnetic particles of iron oxide (USPIO). This experimental method, however, is not commercially available at the moment. Positron emission tomography (PET), a functional imaging technique most commonly accompanied with computed tomography (PET/CT), may also have a role in the detection of bladder cancer LNM in the future. According to the currently available scientific evidence, the following could be recommended for MIBC staging: 1. use of pelvic MRI for primary tumor evaluation and local LNM detection acknowledging limited nodal imaging accuracy; 2. pelvic/abdominal/chest CT for evaluation of distant metastasis. The scientific evidence does not support the routine use of PET/CT (18F-FDG, 18F/11C-choline, 11C-acetate) in bladder cancer staging or in LNM detection.

Systemic exposure to a common periodontal pathogen and missing teeth are associated with metabolic syndrome.

Periodontitis is a common chronic infection of tooth-supporting tissues leading to tooth loss. Two of the major periodontal pathogens are Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Clinically diagnosed periodontitis has been associated with metabolic syndrome (MetS). The aim of the study was to investigate the association of serum antibody levels against A. actinomycetemcomitans and P. gingivalis and the number of missing teeth with MetS. The population was the PAIS subcohort of the FINRISK '97 study (n = 1,354). The subjects were men aged 45-74 years, and they participated in this cardiovascular risk factor survey in Finland. A total of 534 (39 %) subjects had MetS defined according to the guidelines of the International Diabetes Federation. Serum antibody levels against the pathogens were measured by multiserotype ELISA. A. actinomycetemcomitans antibody levels and the number of missing teeth were significantly higher in subjects with a large waist circumference or with low serum high-density lipoprotein cholesterol. The number of missing teeth was also higher among subjects with a high serum triglyceride concentration or high plasma glucose concentration. Seropositivity for A. actinomycetemcomitans was significantly associated with MetS with an odds ratio (OR) 1.42 (95 % confidence interval 1.09-1.85, p = 0.009). More than four missing teeth and complete edentulousness were also significantly associated with MetS with ORs 1.69 (1.26-2.27, p < 0.001) and 1.93 (1.30-2.86, p = 0.001), respectively. Missing teeth and systemic exposure to A. actinomycetemcomitans were associated with several components of Mets. Infection with this common pathogen or the host response against it is associated with the presence of MetS.

Characterization of a novel transgenic rat carrying human tau with mutation P301L.

We have established a novel transgenic rat line carrying human microtubule-associated protein Tau-40 with mutation P301L. hTau-40/P301L transgenic male and female rats were followed up to 2 years of age. The hTau-40/P301L rats expressed human tau mRNA and protein in the limbic cortex and associated white matter, hippocampus and spinal cord. With increasing age, the staining density for phosphorylated tau increased in all these areas. Neither silver stains nor Fluoro-Jade staining indicated the presence of dying neurons, or axonal degeneration, and there was no evidence of increased gliosis or inflammation. However, some neurons did display dendritic abnormalities, and immunoblots revealed the presence of sarcosyl insoluble tau. A large test battery revealed no behavioral abnormalities in these rats, except a mild hyperactivity in the elevated plus maze. In conclusion, this transgenic tau rat may be a useful model for 'pretangle' pathology, although in this study conditions were not sufficient to induce significant neuronal loss or behavioral deficits.

Crystal structures of the CBS and DRTGG domains of the regulatory region of Clostridiumperfringens pyrophosphatase complexed with the inhibitor, AMP, and activator, diadenosine tetraphosphate.

Nucleotide-binding cystathionine beta-synthase (CBS) domains serve as regulatory units in numerous proteins distributed in all kingdoms of life. However, the underlying regulatory mechanisms remain to be established. Recently, we described a subfamily of CBS domain-containing pyrophosphatases (PPases) within family II PPases. Here, we express a novel CBS-PPase from Clostridium perfringens (CPE2055) and show that the enzyme is inhibited by AMP and activated by a novel effector, diadenosine 5',5-P1,P4-tetraphosphate (AP(4)A). The structures of the AMP and AP(4)A complexes of the regulatory region of C. perfringens PPase (cpCBS), comprising a pair of CBS domains interlinked by a DRTGG domain, were determined at 2.3 A resolution using X-ray crystallography. The structures obtained are the first structures of a DRTGG domain as part of a larger protein structure. The AMP complex contains two AMP molecules per cpCBS dimer, each bound to a single monomer, whereas in the activator-bound complex, one AP(4)A molecule bridges two monomers. In the nucleotide-bound structures, activator binding induces significant opening of the CBS domain interface, compared with the inhibitor complex. These results provide structural insight into the mechanism of CBS-PPase regulation by nucleotides.

Age-related macular degeneration: activation of innate immunity system via pattern recognition receptors.

Age-related macular degeneration (AMD) is the most common cause of irreversible loss of central vision. Histopathological studies have demonstrated that inflammation is the key player in the pathogenesis of AMD. Genetic studies have revealed that complement factor H is a strong risk factor for the development of AMD. However, innate immunity defence involves several other pattern recognition receptors (PRRs) which can trigger inflammatory responses. Retinal pigment epithelial (RPE) cells have the main role in the immune defence in macula. In this study, we examine in detail the endogenous danger signals which can activate different PRRs in RPE cells, such as Toll-like, NOD-like and scavenger receptors along with complement system. We also characterise the signalling pathways triggered by PRRs in evoking inflammatory responses. In addition, we will discuss whether AMD pathology could represent the outcome of chronic activation of the innate immunity defence in human macula.

Terpenoids: natural inhibitors of NF-kappaB signaling with anti-inflammatory and anticancer potential.

Traditional medicine has been a fertile source for revealing novel lead molecules for modern drug discovery. In plants, terpenoids represent a chemical defense against environmental stress and provide a repair mechanism for wounds and injuries. Interestingly, effective ingredients in several plant-derived medicinal extracts are also terpenoid compounds of monoterpenoid, sesquiterpenoid, diterpenoid, triterpenoid and carotenoid groups. Inflammatory diseases and cancer are typical therapeutic indications of traditional medicines. Thus folk medicine supports the studies which have demonstrated that plant-derived terpenoid ingredients can suppress nuclear factor-kappaB (NF-kappaB) signaling, the major regulator in the pathogenesis of inflammatory diseases and cancer.We review the extensive literature on the different types of terpenoid molecules, totalling 43, which have been verified both inhibiting the NF-kappaB signaling and suppressing the process of inflammation and cancer. It seems that during evolution, plants have established a terpene-based host defense which also represents a cornucopia of effective therapeutic compounds for common human diseases.

Genetic study between SIRT1, PPARD, PGC-1alpha genes and Alzheimer's disease.

Single nucleotide polymorphisms (SNPs) in three diabetes-related genes (SIRT1, PPARD, PGC-1alpha) were investigated with a case-control approach. To examine the genetic association of those genes with Alzheimer's disease (AD) risk, we used the TaqMan technique to genotype five SNP sites for SIRT1, six for PPARD and eight for the PGC-1alpha gene, in 326 Finnish AD cases and 463 controls and conducted a single allele and genotypic distribution comparison as well as estimated haplotype frequencies between cases and controls. No significant differences in AD risk were found in single SNP and haplotype analyses for any of the three genes between 326 cases and 463 controls. However, in a subgroup of women older than 65 years, the frequencies of three SNPs in the SIRT1 gene were significantly different between AD and controls. We conclude that there is no real association with SNPs available in the present study between SIRT1, PPARD or PGC-1alpha genes and AD risk in the Finnish population.

Interaction of aging-associated signaling cascades: inhibition of NF-kappaB signaling by longevity factors FoxOs and SIRT1.

Research on aging in model organisms has revealed different molecular mechanisms involved in the regulation of the lifespan. Studies on Saccharomyces cerevisiae have highlighted the role of the Sir2 family of genes, human Sirtuin homologs, as the longevity factors. In Caenorhabditis elegans, the daf-16 gene, a mammalian homolog of FoxO genes, was shown to function as a longevity gene. A wide array of studies has provided evidence for a role of the activation of innate immunity during aging process in mammals. This process has been called inflamm-aging. The master regulator of innate immunity is the NF-kappaB system. In this review, we focus on the several interactions of aging-associated signaling cascades regulated either by Sirtuins and FoxOs or NF-kappaB signaling pathways. We provide evidence that signaling via the longevity factors of FoxOs and SIRT1 can inhibit NF-kappaB signaling and simultaneously protect against inflamm-aging process.

The expression of heat shock protein 27 in retinal ganglion and glial cells in a rat glaucoma model.

The heat shock protein 27 kDa (HSP27) is a member of proteins that are highly inducible under various forms of cellular stress. This study describes constitutive HSP27 expression in rat retina and stress-associated expression of HSP27 in an experimental rat glaucoma model. Glaucoma was induced unilaterally using laser photocoagulation of the episcleral and limbal veins. Three and seven days after the elevation of intraocular pressure (IOP), groups of rats were killed. The second laser treatment was performed for those rats killed 14 and 21 days after the first laser treatment. The RGCs were labeled with a retrograde tracer 7 days before kill. The expression of HSP27 was analyzed by Western blotting in retinas of rats killed on day 14 after the first laser treatment. Retinal astrocytes, Müller cells and HSP27-positive cells were visualized using immunohistochemical methods both from retinal whole-mounts and paraffin sections. The total number of retrogradely labeled RGCs decreased by 23.2% after 7 days, 28% after 14 days, and 29.3% after 21 days of elevated IOP when compared with controls. A significant decrease of glial fibrillary acidic protein (GFAP)-immunoreactive retinal astrocytes in laser-treated eyes was observed compared with the controls (accounted for 44.9%, 38.2% and 35% of the control values in the 7-day, 14-day and 21-day groups, respectively). The expression of HSP27 in RGCs and retinal astrocytes was also increased in laser-treated eyes when compared with controls in all groups. However, glycinergic and cholinergic cells in the inner nuclear layer and the highest number of RGCs and astrocytes that expressed HSP27 were found in the 14-day group of rats. The constitutive expression of HSP27 was observed only in retinal astrocytes and Müller cells. This study suggests that constitutive HSP27 expression is a cell-type specific phenomenon in the rat retina. However, at the same time, HSP27 might be considered as a marker for neuronal injury in the rat glaucoma model.

In vitro biocompatibility of degradable biopolymers in cell line cultures from various ocular tissues: direct contact studies.

Synthetic biodegradable polymers have many potential therapeutic applications. In ophthalmology, biodegradable polymers have been used as viscoelastic agents and surgical implants. Other potential applications include controlled release of drugs and growth factors, gene therapy, and tissue engineering. In the present study, in vitro biocompatibility of three biodegradable polymers, 50:50 PDLGA, 85:15 PDLGA, and Inion GTR membrane was evaluated in comparison to tissue culture polystyrene by investigating cell proliferation and potential acute toxicity by the WST-1 cytotoxicity/cell proliferation test, the ATP test, and the lactate dehydrogenase (LDH) test. Evaluations were conducted with cell line cultures from various ocular tissues, human corneal epithelial cells (HCE), rabbit stromal fibroblasts (SIRC), bovine corneal endothelial cells (BCE), human conjunctival epithelial cells (IOBA-NHC), and human retinal pigment epithelial cells (ARPE-19) by direct contact studies by plating the cells on the polymer film specimens in 96-wells. The proliferation results show that cell lines from various ocular tissues attached and grew on PDLGA 50:50, PDLGA 85:15, and Inion GTR membrane. Cytotoxicity experiments with the LDH and ATP tests showed no or extremely slight toxic adverse effects. These polymers have potential to be used as scaffolds in cell transplantation devices or as surgical implants.

Two soluble pyrophosphatases in Vibrio cholerae: transient redundancy or enduring cooperation?

Soluble pyrophosphatases (PPases), which are essential for cell life, comprise two evolutionarily unrelated families (I and II). Prokaryotic genomes generally contain a single PPase gene encoding either family I or family II enzyme. Surprisingly, four Vibrionales species, including the human pathogen Vibrio cholerae, contain PPase genes of both families. Here we show that both genes are transcriptionally active in V. cholerae, and encode functional PPases when expressed in Escherichia coli. In contrast, only the family I PPase protein is detected in V. cholerae under our experimental conditions. Phylogenetic analyses indicate that family II enzymes are not native to gamma-proteobacteria, but are of benefit to the marine species of this bacterial class. In this context, we favor the hypothesis that in the course of evolution, family II PPase was laterally transferred to the Vibrionales ancestor and partially degenerated due to functional redundancy, but nevertheless remained fixed as an adjunct to the family I enzyme.

Anti-inflammatory effect of selective estrogen receptor modulators (SERMs) in microglial cells.

OBJECTIVE: Our aim was to study how different SERMs modulate the inflammatory responses induced by lipopolysaccharide (LPS) or unmethylated CpG-oligonucleotides in mouse and rat microglial cells. MATERIALS AND METHODS: Inflammatory responses of mouse N9 microglial cells and rat primary hippocampal microglia to lipopolysaccharide (LPS) exposure were recorded by the secretion of nitric oxide (NO) and cytokine IL-6 in two models where SERM was added either 24 h before LPS addition or simultaneously or even after the LPS exposure. The responses of 17beta-estradiol, tamoxifen, raloxifene and ICI 182.780 were compared. Responses were recorded by ELISA, Northern and EMSA assays. RESULTS: SERMs but not 17beta-estradiol induced a significant, concentration-dependent anti-inflammatory response both in rat primary microglial cells and in mouse N9 microglial cells. The response was observed both in NO and IL-6 secretion as well as in total IL-6 mRNA expression. We have recently observed that histone deacetylase (HDAC) inhibitors can potentiate the LPS-induced inflammatory response. Raloxifene and tamoxifen inhibited the potentiation of LPS response induced by trichostatin A, an HDAC inhibitor, in N9 microglia. A SERM-induced anti-inflammatory response was observed in acute models where SERM was added simultaneously or even up to 6 h later than LPS exposure. In contrast, the pretreatment of N9 microglia with tamoxifen or raloxifene for 30 h before LPS exposure did not provide any protection against the LPS response. We also observed that the raloxifene-induced protection in N9 microglia was connected to a decline of LPS-induced DNA binding activity of AP-1 but not that of NF-kappaB transcription factors. CONCLUSIONS: Our results show that tamoxifen, raloxifene and ICI 182.780 induce an anti-inflammatory response in acute models of mouse and rat microglial cells. It seems that this response is not estrogen receptor-mediated but, probably, is attributable to some SERM-induced modulation of LPS-activated pro-inflammatory signalling cascades.