BackgroundInteractions between adipocytes and macrophages are associated with metabolic disorders. Production of pro-inflammatory mediators and the release of free fatty acids (FFAs) increase when these cells are co-cultured; butyrate significantly diminishes these effects by suppressing both the macrophage inflammatory and adipocyte lipolysis pathways. Butyrate is known to up-regulate the expression of prostaglandin E2 (PGE2). Therefore, we hypothesized that PGE2 is associated with the suppression of lipolysis by butyrate in co-culture.MethodsUsing contact or transwell co-culture methods with differentiated 3T3-L1 adipocytes and RAW264.7 macrophages, we investigated the effects of butyrate on the release of PGE2 into the medium and on lipolysis in adipocytes. To elucidate the underlying mechanism, we examined the effects of butyrate on cyclooxygenase-2 (COX2) and phospholipase A2 (PLA2) in co-cultured cells, and cyclic adenine monophosphate (cAMP) and protein kinase A type 1-α regulatory subunit (PRKAR1A) in co-cultured adipocytes. Silent interfering (si)RNA targeting of G-protein–coupled receptor (GPR)41 and 109A was employed to examine the effect on lipolysis in TNF-α–stimulated adipocytes.ResultsCo-culture increased PGE2 release into the medium, compared with cells cultured separately. Butyrate significantly increased PGE2 production. Co-culture elevated COX2 expression in macrophages and adipocytes, and butyrate further enhanced this effect. Co-culture enhanced cytosolic PLA2 activity in macrophages, which was further enhanced by butyrate. As for lipolysis, co-culture increased the release of FFAs and free glycerol into the medium, whereas butyrate (and to a lesser extent, PGE2) suppressed FFAs and free glycerol release. An inhibition study using a prostaglandin E receptor 3–selective antagonist suggested that approximately 40% of the suppressive effect of butyrate depends on the PGE2-mediated pathway, whereas 60% depends on a non-PGE2–mediated pathway. Co-culture increased cAMP and PRKAR1A levels in adipocytes, whereas butyrate restored the levels to those of the control. Similarly, in TNF-α–stimulated adipocytes, butyrate reduced FFAs and free glycerol release. siRNA inhibition of GPR41 and GPR109A suggested that the GPR109A-mediated pathway predominates, but the GPR41-mediated pathway also regulates the effect of butyrate on lipolysis in TNF-α–stimulated 3T3-L1 cells.ConclusionsButyrate attenuates lipolysis in adipocytes co-cultured with macrophages via non-PGE2–mediated and PGE2-mediated pathways.

The modified sample preparation for MALDI-TOF MS can improve identification accuracy for complicated UTI causative bacteria. This simple modification offers a rapid and accurate routine diagnosis for UTI, and may possibly be a substitute for urine cultures.

BackgroundEvaluating patient global VAS is one of the most essential process in RA practice. Despite reliability of patient global VAS being highly important in clinical practice, there has been no study comparing global VAS scores obtained at hospitals and those obtained at home where patients answer anonymously.ObjectivesTo compare the patient global VAS obtained before clinical examination in hospital with those answered anonymously at home.MethodsWe asked RA patients to answer and mail the EQ5D data set anonymously. EQ5D consisted of 5 component questions (mobility, self-care, usual activities, pain/discomfort, anxiety/depression) and patient assessment global health VAS. EQ5D global VAS is anonymized patient global VAS evaluated at home. We compared the patient global VAS which is routinely surveyed at hospital before clinical examination with those surveyed anonymously at home.ResultsThe anonymized VAS score was higher than those routinely evaluated at hospital (p<0.0001). Global VAS scores obtained at hospital poorly correlated with those obtained anonymously at home (r=0.426). We compared patients who had higher patient global VAS at hospital than anonymized VAS at home with patients who had lower patient global VAS at hospital than anonymized VAS at home. Pain VAS scores remained to be risk factor to be higher anonymized VAS at home than those routinely evaluated at hospital after multivariate analysis.ConclusionsDiscrepancy exists between patient global VAS evaluated in the hospital before clinical examination and those evaluated anonymously at home. There is a possibility that patients rating high pain VAS are underrating their global VAS scores at hospital.Disclosure of InterestNone declared

Cutibacterium modestum is a new species coined in 2020 as the fifth species of genus Cutibacterium, which includes Cutibacterium acnes. The species is predicted as a minor but common member of skin microbiome and includes a group tentatively named as “Propionibacterium humerusii”. The description of the species has been provided only with a single strain. To establish the characteristics of C. modestum and search for possible disease-related subtypes, we investigated the biochemical characteristics of eight live strains and performed in silico comparison of nine genomes. The common features, which included the morphology of Gram-stain positive short rods, the negativity of phenylalanine arylamidase, and several unique MALDI-TOF MS spectral peaks, were considered useful in laboratory identification. Pairwise comparisons of the genomes by in silico DNA–DNA hybridization showed similarity values of 98.1% or larger, which were far higher than the subspecies cutoff of 79–80%. The 16S rRNA gene sequences of thirteen isolates and genomes were identical. Their recA gene sequences were identical except for two strains, HM-510 (HL037PA2) and Marseille-P5998, which showed unique one-nucleotide polymorphisms. The biochemical features using API kits were slightly different among the isolates but far closer than those of the nearest other species, C. acnes and Cutibacterium namnetense. Spectra of MALDI-TOF mass spectrometry showed slight differences in the presence of m/z 10,512 (10 kD chaperonin GroS) and three other peaks, further clustering the eight isolates into three subtypes. These results indicated that these isolates did not separate to form subspecies-level clusters, but subtyping is possible by using recA gene sequences or MALDI-TOF mass spectrometry spectra. Moreover, this work has confirmed that a group “P. humerusii” is included in C. modestum.

Background Primary Sjögren's syndrome (pSS) is an autoimmune exocrinopathy characterised by the infiltration of mononuclear cells into salivary and lacrimal glands leading to destruction of the parenchymal tissue and causing oral and ocular dryness. Omics studies such as genomics, proteomics and metabolomics have been extensively used to elucidate biological mechanisms of diseases through collective characterization and quantification of pools of biological molecules and generating molecular profiles for biospecimens. Saliva contains a variety of informative substances which may closely reflect the pathogenetic process of pSS in salivary glands. In fact, salivary proteomics from pSS patients have detected some proteins as biomarkers for pSS diagnosis. To date, metabolomics has been widely conducted and is regarded as the end point of “omics cascade” and most predictive of phenotype. However, salivary metabolomics from pSS patients has not been reported up-to-date. Objectives To compare the salivary metabolite profile between patients with pSS and healthy control (HC) subjects. Methods We obtained saliva from 12 female pSS patients (mean age 44.2±13.01) and 21 age-matched female HCs by spitting for 15 minutes. The metabolite profile of saliva specimens were analyzed by gas chromatography-mass spectrometry. The levels of metabolites were calibrated by saliva volume per 15 minutes enabling us to compare the metabolite production level of whole salivary glands for 15 minutes. Results 88 metabolites were detected by our system. 32 metabolites were decreased and only one metabolite was increased in pSS patients. Principal component analysis (PCA) revealed a loss in salivary metabolite diversity in pSS patients compared to HCs. The decrease of Glysine, Tyrosine, Uric Acid and Fucose which may reflect the destruction of salivary gland due to chronic sialoadenitis contributed to the loss of diversity. PCA amongst pSS patients revealed that pSS could be divided into two subpopulations according to their metabolite profiles and the prevalence of major salivary glanditis was different between the two subpopulations (p=0.014). Conclusions In this preliminary study, the salivary metabolite profile of pSS patients was less diverse compared to controls. Salivary metabolite profile was affected by the presence of major salivary glanditis suggesting that salivary metabolomics may serve as a prospective approach to discover the underlying pathogenesis of pSS. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.1201