AB0301 ANALYSIS OF INTESTINAL MICROBIOTA IN PATIENTS WITH OSTEOPOROSIS SECONDARY TO RHEUMATOID ARTHRITIS

Objectives

To analyse of intestinal microbiota in patients with osteoporosis (OP) secondary rheumatoid arthritis (RA).

Methods

Design: A cross-sectional observational study nested in a prospective cohort of incident RA patients.

Patients: Patients with RA (ACR/EULAR 2010) from a prospective baseline cohort (incident cases between 2007-2011), >16 years, from whom information on bone mineral densitometry (BMD) was collected.

Protocol: all subjects were evaluated in a specialized outpatient unit. Clinical-analytical variables of the cut-off date and clinical history were registered. Blood, urine and faeces samples were obtained from all subjects. A BMD was done by dual energy X-ray absorptiometry (DXA) for osteoporosis diagnosis.

Variables: Dependent variable: osteoporosis according World Health Organization (WHO) definitions. The fecal microbiota (continuous var., 0-100%) was analysed using the Ion Torrent S5 next-generation sequencing platform, and the sequences obtained were processed using the QIIME2 (Quantitative Insights Into Microbial Ecology 2) software. Others variables included demographics characteristics, comorbidities, inflammatory activity measured by mean accumulated Disease Activity Score-28 (DAS-28) throughout the disease, severity variables: smoking, erosions, anticitrullinated peptide antibody (ACPA) titres, rheumatoid factor (RF) and physical function measured by HAQ. Treatment with bDMARD (biological disease-modifying antirheumatic drug) and/or sDMARD (synthetic disease-modifying antirheumatic drug).

Statistical Analysis: descriptive, bivariate using χ2 and T-Student followed by logistic multivariant regression model in patients with RA. (Vd: Osteoporosis).

Results

110 patients with RA were included. The majority of the subjects were women (80%) with an average age of 56 years. The majority of patients were seropositive (81.8% with positivity for RF and 80% with positive for ACPA) and the accumulated DAS-28 average was 3. A total of 49/110 (44.5%) had normal BMD, 46/110 patients (41.8%) had densitometric osteopenia and 15/110 OP (13.6%). Patients with OP were older (p=0.025), higher RA length (p=0.003), higher CRP (p=0.046), higher inflammatory by DAS-28 (p=0.051) and higher ACPA titres (p=0.043). Furthermore, they showed higher levels of Lentisphaerae (p=0.035), Synergistetes (p<0.001), Actinobacteria (p=<0.001) y Verrucomicrobia (p=0.034).

The variables independently associated with OP in RA were: age (OR [IC 95%],1.099 [1.012-1.193]; p=0.025), ACPA (OR [IC 95%],1.005 [1.001-1.010]; p=0.036), RA length (OR [IC 95%],1.039 [1.016-1.062]; p=0.001) y Actinobacteria (OR [95% CI] 1.124 [1.004-1.257]; p=0.042), R2=0.367.

Conclusion

Osteoporosis in Rheumatoid Arthritis is associated with severity factors as the age, the disease length or the presence of ACPA, as well as the Actinobacteria predominance in the intestinal microbiota.

Table 1.

Epidemiological, clinical and analytical characteristics of patients

VariablePatients n=110Epidemiological characteristicsAge in years, mean (IQR)55.9 (49.3-64.4)Sex, female; n (%)88 (80.0)Tobacco Never smoker, n (%)47 (42.7) Ex-smoker, n (%)30 (27.3) Active smoker, n (%)33 (30.0)Comorbidities High blood pressure, n (%)28 (25.5) Diabetes Mellitus, n (%)6 (5.5) Dyslipidemia, n (%)25 (22.7) Cardiovascular Disease, n (%)18 (16.4) BMI (Kg/m2), mean (SD)28.4 (5.1)Clinical and analytical characteristicsRA evolution time, months, median (IQR)93.2 (77.6-123.4)Diagnosis delay, months, median (IQR)8.1 (4.5-17.0)Erosions, n (%)68 (61.8)RF >10, n (%)90 (81.8)ACPA >20, n (%)88 (80.0)DAS-28 average, mean (±SD)3.0 (0.7)HAQ average, median (IQR)0.71 (0.3-0.9)sDMARD, n (%)93 (84.5)bDMARD, n (%)42 (38.1)Osteopenia, n (%)46 (41.9)Osteoporosis, n (%)15 (13.6)

Disclosure of Interests

Alba María Cabezas-Lucena: None declared, Maria Morales-Águila: None declared, Patricia Ruiz-Limon: None declared, Isabel Moreno-Indias: None declared, Natalia Mena-Vázquez: None declared, Sara Manrique Arija Speakers bureau: Abbvie, Gedeon, Jansen, Lilly, Menarini, MSD, Novartis, Pfizer, Roche, Sanofi, UCB, Consultant of: Abbvie, Jansen, Lilly, Novartis, Sanofi, Antonio Fernandez-Nebro: None declared

SAT0362 ASSOCIATION OF GUT DYSBIOSIS WITH STRUCTURAL DAMAGE AND ACTIVITY IN AXIAL SPONDYLOARTHRITIS PATIENTS. DATA FROM THE COSPAR REGISTRY

Background:

The etiopathogenesis of axial spondyloarthritis (AxSpA) is multifactorial. The possible role of alteration in gut microbiome (dysbiosis) has been recently suggested. However, the association of dysbiosis with structural damage is still unknown and further studies are needed to assess its association with disease activity.

Objectives:

To determine the alterations in the gut microbiota in AxSpA patients. To evaluate whether changes in the gut microbiota in AxSpA patients are associated with structural damage or disease activity.

Methods:

Fifteen AxSpA patients and 15 healthy donors (HDs) were included in a cross-sectional study. Disease activity variables such as C-reactive protein and ESR were measured. Structural damage was determined by lateral X-rays of the cervical and lumbar spine to establish the mSASSS index. Axial mobility was evaluated using the BASMI index and the enthesis affectation was evaluated using ultrasound to obtain the MASEI index. Gut microbiota was measured using the Ion Torrent S5 platform and sequences were processed using the QIIME2. Chi-square and Mann-Whitney U were used, and correlations were determined using the Spearman Rho test. Significant differences were considered p <0.05.

Results:

Alpha diversity indicators, such as the number of observed OTUs group and the faith index, showed a greater richness in AxSpA compared to HDs (p=0.03 and p=0.01). A significant decrease in family Bacteroidaceae (p=0.006) and an increase in families Synergistaceae and Bifidobacteriaceae were found in the microbiota of AxSpA (p=0.036, p=0.049). According to genera, Bacteroides decreased in AxSpA (p=0.006), while Dialister and Bifidobacterium increased (p=0.010 and p=0.046). Positive correlation among lumbar mSASSS (r=0.508, p=0.019) and Synergistaceae was found. This family was also increased along with the increase in enthesis damage (MASEI index (r=0.656, p=0.028)) and axial mobility by the BASMI index (r=0.529, p=0.011). Correlation studies between the decrease in Bacteroidaceae and Bacteroides with disease activity measured by ASDAS (r=-0.697, p=0.025; r=-0.770, p=0.009) was also significant. Positive correlation was observed between Dialister with mSASSS (r=0.549, p=0.010) and BASMI (r=0.512, p=0.015).

Conclusion:

1) AxSpA patients had a significant alteration of the gut microbiota. 2) These alterations are associated with radiographic damage, disease activity, affectation of enthesis and axial mobility.

Acknowledgments:

PRL, supported by “Sara Borrell” (CD19/00216), IMI supported by “Miguel Servet tipo I” (CP16/00163), CGR supported by JdC Incorporación (IJCI-2017-33065). This work is supported by JA PI-0151-2018. Pablo Rodríguez Bada metagenomic platform CIBER-IBIMA.

Disclosure of Interests:

Gómez García Ignacio: None declared, Isabel Moreno-Indias: None declared, María del Carmen Castro Villegas: None declared, Maria del Carmen Abalos-Aguilera: None declared, MLourdes Ladehesa Pineda: None declared, Inmaculada Concepcion Aranda-Valera: None declared, Carolina Gutierrez Repiso: None declared, Alejandro Escudero Contreras Grant/research support from: ROCHE and Pfizer, Speakers bureau: ROCHE, Lilly, Bristol and Celgene., Jiménez Gómez Yolanda: None declared, Nuria Barbarroja: None declared, Francisco Jose Tinahones: None declared, Eduardo Collantes Estevez Grant/research support from: ROCHE and Pfizer, Speakers bureau: ROCHE, Lilly, Bristol and Celgene, Patricia Ruiz-Limon: None declared

Use of glycerol and propylene glycol as additives in heat-treated goat colostrum

This experiment aimed to evaluate the suitability of glycerol and propylene glycol to reduce microbial count and preserve immune properties in heat-treated goat colostrum. Colostrum samples from 11 goats were each divided into 9 aliquots. Different concentrations (2, 6, 10, and 14%; vol/vol) of either glycerol or propylene glycol were added to the aliquots. Phosphate buffer solution was added to one aliquot, which was set as the control (CG). After the respective additions, all colostrum samples were heat treated at 56°C for 1 h. After cooling, aerobic mesophilic bacteria were cultured. The samples were frozen until free fatty acid, IgG, IgA, and IgM concentrations and chitotriosidase activity were measured. No differences were found in aerobic mesophilic bacteria counts between either 10 or 14% glycerol and propylene glycol additives. These additions reduced bacterial count to a greater extent than CG, and 2 or 6% additions. Colostrum IgG concentration was not affected by either of the additives or their concentrations. The propylene glycol additive reduced IgA and IgM concentrations and chitotriosidase activity, compared with CG. Conversely, glycerol did not affect any of the studied immune variables. In conclusion, glycerol addition to goat colostrum before heat treatment is suitable to enhance bacterial reduction, whereas colostrum immune properties were not affected.

Molecular effect of fenofibrate on PBMC gene transcription related to lipid metabolism in patients with metabolic syndrome

BACKGROUND

Both fasting and postprandial hypertriglyceridaemia are considered independent risk factors for atherosclerosis. Treatment of hypertriglyceridaemia is based on fibrates, which activate the peroxisome proliferator-activated receptor alpha (PPARα). However, the metabolic pathways that activate or inhibit fibrates, and how the postprandial triglyceride levels are modified, have not yet been fully described. Accordingly, the aim of this study was to determine the feasibility of peripheral blood mononuclear cells (PBMC) to study the effects of fenofibrate in patients with the metabolic syndrome.

MATERIALS AND METHODS

A fat overload was given to 50 patients before and after treatment with fenofibrate for 3 months. Anthropometric and biochemical variables as well as gene expression in PBMC were analysed.

RESULTS

After treatment with fenofibrate, we observed a decrease in both baseline and postprandial (3 h after the fat overload) levels of serum triglycerides, cholesterol and uric acid and an increase in HDL cholesterol and apolipoprotein AI levels. After treatment, there was also a rise in PPARα and RXRα expression and changes in genes regulated by PPARα, both baseline and postprandial. Furthermore, in vitro experiments showed that a PPARα agonist changed the expression of genes related with lipid metabolism.

CONCLUSION

Treatment with fenofibrate reduced fasting and postprandial serum triglyceride levels, possibly through a mechanism related with an increase in the expression of RXRα and PPARα, by activating the pathways involved in the uptake and degradation of triglycerides and increasing the synthesis of apolipoprotein. These results suggest that PBMC may be useful for the easy study of fenofibrate actions.

From goat colostrum to milk: physical, chemical, and immune evolution from partum to 90 days postpartum

This study focused on the study of the changes originated in the milk from partum until d 90 of lactation. Ten multiparous Majorera goats, bred carefully under animal health standards, with a litter size of 2 kids (the average in this breed is 1.83 prolificacy) and similar gestation length (149 ± 1 d) were used. Goat kids were removed from their dams to avoid interferences with the study. Compositional content (fat, protein, and lactose) were measured, as well as some other properties, including pH, density, titratable acidity, ethanol stability, rennet clotting time, and somatic cell count. Moreover, immunity molecules (IgG, IgA, and IgM concentrations and chitotriosidase activity) received great attention. Fat and protein content were higher in the first days postpartum, whereas lactose content was lower. Density, titratable acidity, rennet clotting time, and somatic cell count decreased throughout the lactation period, whereas pH and ethanol stability increased. Relative to the immunological parameters, each measured parameter obtained its maximum level at d 0, showing the first milking as the choice to provide immunity to the newborn kids. On the other hand, this study might be used to establish what the best use is: processing or kid feeding.

Physicochemical analysis of full-fat, reduced-fat, and low-fat artisan-style goat cheese

The objective of this study was to examine the physicochemical properties of cheese elaborated via traditional artisan methods using goat milk containing 5, 1.5, or 0.4% fat and ripened for 1, 7, 14, or 28 d. Seventy-two cheeses were produced (2 batches x 3 fat levels x 4 ripening times x triplicate). Proximal composition, pH, texture analysis, and color were recorded in each cheese. Protein and moisture were increased in cheese, and fat and fat in DM were decreased with decreasing fat in milk. Internal and external pH was higher in low-fat and reduced-fat cheese, and pH values decreased during the first 2 wk of ripening but increased slightly on d 28. Cheese fracturability, cohesiveness, masticability, and hardness increased with decreasing fat, whereas elasticity and adhesiveness decreased. Cheese lightness and red and yellow indexes decreased with decreasing fat content; during ripening, lightness decreased further but yellow index increased.

Effect of colostrum immunoglobulin concentration on immunity in Majorera goat kids

The aim of the research was to evaluate the effects of immunoglobulin G (IgG) colostrum concentration on goat kid immune status when the total amount of IgG fed was constant. Majorera goat kids (n = 56) were randomly assigned to 1 of 4 groups, and kids received 4 g of IgG per kg of body weight of atomized colostrum at 4 different IgG concentrations: 20 (AC-20), 40 (AC-40), 60 (AC-60), and 80 (AC-80) mg/mL. Blood samples were obtained on d 0, 1, 2, 3, 4, and 5 postpartum. Immunoglobulin G, IgA, and IgM plasma concentrations, apparent efficiency of absorption of IgG, plasma chitotriosidase activity, plasma complement activity, and plasma proteinogram were measured. Plasma IgG and IgM concentrations were highest on d 1 in AC-80 animals, and IgA plasma concentration was lower in AC-20 than in AC-80. The apparent efficiency of absorption was higher in AC-80 (24.4%) than in the other treatment groups (by an average of 13.8%). Chitotriosidase plasma activity on d 5 (1,488 nmol/mL per hour) was higher than on d 0 and 1 (average of 1,183 nmol/mL per hour). There were no effects of colostrum IgG concentration on complement activity and plasma protein distribution, but gamma-globulin and alpha-globulin were lower on d 0 than on d 1, 2, 3, 4, and 5. Increasing the immunoglobulin concentration in colostrum using atomized colostrum improves the immunoglobulin absorption at the same amount of immunoglobulin fed.

Short communication: apoptosis regulates passive immune transfer in newborn kids

Ten newborn kids were used to evaluate the relationship between apoptosis and passive immune transfer in neonatal enterocytes. Kids were slaughtered in groups of 2 at birth, 1, 2, 3, or 60 d postpartum, and samples of duodenal epithelium collected from each animal. Samples were fixed, dehydrated, and embedded in paraffin wax. Sections were assessed for apoptotic cells and immunostained for IgG. Our results suggest that IgG absorption is mediated by apoptotic enterocytes. Thus, delaying apoptosis may improve the success of passive immune transfer.