Effect of low dietary lipid on the development of Sjögren's syndrome and haematological abnormalities in (NZB x NZW)F1 mice

High-fat diet-induced intestinal dysbiosis is associated with the exacerbation of Sjogren’s syndrome

Environmental factors are believed to influence the evolution of primary Sjögren’s syndrome (pSS). The aims of this study were to investigate the association of pSS with a high-fat diet (HFD) and to relate HFD-induced gut dysbiosis to pSS exacerbation. Male Wild Type (WT) and IL-14α transgenic mice (IL-14α TG) were fed a standard diet (SD) and HFD for 11 months. We found an increase in the autoantibody level, more severe dry eye, severe dry mouth symptoms, and an earlier presence of systemic features in the IL-14α TG mice treated with HFD. These data suggest that HFD can promote the process of pSS in the IL-14α TG mice. In addition, an HFD leads to a decrease in the richness of gut microbiota of IL-14α TG mice treated with HFD. The abundance of Deferribacterota was significantly enriched in the IL-14α TG mice treated with HFD compared with other groups. Through the mental test between gut microbiota and clinical parameters, we found that HFD-induced dysbiosis gut microbiota were associated with pSS clinical parameters. In conclusion, HFD results in the aggravation of pSS progression, likely due to the increase of potentially pathogenic microorganisms.

Cardiovascular risk factors in primary Sjögren's syndrome: a case-control study in 624 patients

We evaluated the prevalence and clinical significance of cardiovascular risk factors in a large series of patients with primary Sjögren’s syndrome (SS), focusing on the possible association with clinical and immunological SS features, the therapies administered, and the impact on cardiovascular disease. The study cohort included 312 patients fulfilling the 2002 classification criteria for primary SS, consecutively evaluated and followed in our department between 1984 and 2009. The control group consisted of 312 age- and sex-matched patients without systemic autoimmune diseases followed during the study period in a primary care centre.

In comparison with the age- and sex-matched control group, patients with primary SS showed a higher frequency of diabetes mellitus (27% versus 13%, p < 0.001) and hypertriglyceridaemia (22% versus 15%, p = 0.023), and a lower frequency of hypertension (30% versus 46%, p < 0.001) and smoking (19% versus 31%, p < 0.001). The adjusted, multivariate analysis showed that SS patients with at least three cardiovascular risk factors had a higher mean age at SS diagnosis (p < 0.001), a higher frequency of liver involvement (p = 0.01) and central nervous system involvement (p = 0.001), higher mean levels of C-reactive protein (CRP, p = 0.001), a lower percentage of circulating gamma globulins (p = 0.001), and had received corticosteroids more frequently (p = 0.003) in comparison with patients without cardiovascular risk factors. Patients who had received corticosteroids showed a higher frequency of hypertension (37% versus 25%, p = 0.032), diabetes mellitus (37% versus 21%, p = 0.002), and hypertriglyceridaemia (33% versus 15%, p < 0.001).

Patients with primary SS showed a twofold higher prevalence of diabetes mellitus and a 1.5-fold higher prevalence of hypertriglyceridaemia in comparison with primary care patients. Corticosteroid use was closely associated with cardiovascular risk factors. These results suggest that cardiovascular risk factors should be taken into account in the management of patients with primary SS and show the importance of recognizing and controlling both traditional and SS-related modifiable risk factors.

Nutrient intake in women with primary and secondary Sjögren's syndrome

OBJECTIVE

Recently, it has been proposed that dietary factors may contribute to the etiology and progression of Sjögren's syndrome, and that nutritional intervention may modify the severity of pathological abnormalities. The objective of this study was to determine whether the nutrient intake of women with primary (1 degrees SS) or secondary (2 degrees SS; ie with systemic lupus erythematosus (2 degrees SS/SLE) or rheumatoid arthritis (2 degrees SS/RA) Sjögren's syndrome is significantly different than that of age- and gender-matched controls.

DESIGN

Women with Sjögren's syndrome were asked to complete the 97 General Purpose Semi-Quantitative Food Frequency Questionnaire, which consists of a list of 147 separate food items that represent the major sources of multiple nutrients. Nutritional data were evaluated in terms of absolute and energy-adjusted nutrient amounts and analyzed by ANOVA.

RESULTS

Our results showed: (a) greater intake of energy, glutamate, carbohydrates, lactose, phosphorus, caffeine and unsupplemental thiamin and riboflavin in 1 degrees SS, as well as supplemental calcium in 2 degrees SS/SLE, compared with controls; (b) greater nutrient intake of energy, protein, glutamate, methionine, tryptophan, carbohydrates, lactose, supplemental calcium and phosphorus, sodium, caffeine and unsupplemental calcium, riboflavin and thiamin in 2 degrees SS/RA, relative to 1 degrees SS and/or 2 degrees SS/SLE; (c) higher energy-adjusted values for supplemental calcium in 2 degrees SS/SLE, and for vitamin A and supplemental iron and zinc in 2 degrees SS/RA, compared with other groups; and (d) higher energy-adjusted intake of supplemental calcium, and a lower energy-adjusted intake of unsupplemental vitamin C, polyunsaturated fat, linoleic acid, omega-3 fatty acid, and specific other unsaturated fatty acids, in the Sjögren's syndrome group as a whole, relative to controls.

CONCLUSIONS

Our findings demonstrate that nutrient intake is altered in Sjögren's syndrome.

Relationship between sialoadenitis and periductal laminin expression in the submandibular salivary gland of NZBxNZWF(1) mice

This study was designed to investigate the relationship between cellular infiltration and periductal laminin expression of the submandibular salivary gland in female autoimmune NZBxNZWF(1) mice, which are used as an animal model for secondary human Sjögren's syndrome. In NZBxNZWF(1) mice, but not in non-autoimmune control (BALB/c) mice, early submandibular salivary gland lesions were characterized by infiltration of mononuclear cells around vessels and ducts in the interstitial tissues, increasing with age. Destruction and hyperplasia of ductal epithelial cells occurred, with extensive local infiltration of mononuclear cells. Laminin expression around the ducts was significantly higher in young NZBxNZWF(1) mice than that in control (BALB/c and DBA/1) mice. Periductal laminin expression increased in NZBxNZWF(1)mice with age. In addition VLA-6, which is a ligand for laminin, was expressed by the infiltrating cells. These results suggest that laminin expression is associated with the cellular infiltration of the submandibular salivary gland of NZBxNZWF(1) mice.

Calorie restriction decreases proinflammatory cytokines and polymeric Ig receptor expression in the submandibular glands of autoimmune prone (NZB x NZW)F1 mice

Calorie restriction or fish oil (enriched in n-3 fatty acids) supplementation ameliorates glomerulonephritis and Sjögren's syndrome lesions in (NZB x NZW)F1(B/W) mice. Enhanced proinflammatory cytokine expression and deposition of immune complexes are the important pathological events in the development of Sjögren's syndrome. In the present study, we have examined the effect of calorie restriction and fish oil supplementation on the expression of key inflammatory cytokines [gamma interferon (INF-gamma), interleukin-10 (IL-10), and IL-12] and polymeric immunoglobulin (Ig) receptor (pIgR) (receptor for IgA and IgM) and the secretion of Ig in the submandibular glands (SMG) of B/W mice. Weanling B/W mice were fed either ad libitum (AL) or calorie restricted (CR) (40% less calories than AL) diet supplemented with 5% corn oil (CO) or 5% fish oil (FO) until 4 or 9 months of age. The SMGs were removed and a portion of the tissue used for semiquantitive determinations of IFN-gamma, IL-10, IL-12 (p40), and pIgR mRNA. The remaining SMG tissue was fragmented and cultured for 7 days and the culture supernatants assayed for IgA, IgM, and IgG2a levels by enzyme-linked immunosorbent assay. Results revealed a significant increase in the expression of IFN-gamma, IL-10, and IL-12 mRNA with age in AL fed mice, whereas CR fed mice maintained their levels to near those seen in young animals regardless of the dietary fat. PIgR mRNA expression also remained unaltered in CR animals irrespective of age and dietary fat, while it was found significantly increased in AL fed mice. CR significantly inhibited the elevated levels of IgA and IgG2a seen in aged mice. Interestingly, CR also influenced the Ig level in young animals. In summary, these results indicate that amelioration of autoimmune disease by CR in B/W mice is possibly mediated by the lowered mRNA expression of IFN-gamma, IL-10, IL-12, and pIgR and the reduced Ig secretion.

Haematopathology of 'Sjögren-mice': histopathological changes in spleens after semiallogeneic cell transfer

Haematopoietic transplantation chimeras may be readily produced in adult mice, using F1-hybrids of selected inbred strains as recipients and mice from one of the parental strains as donors. We transplanted spleen cells from BALB/c donors into nonirradiateded F1-hybrids of BALB/c and CBA/H-T6. Both female and male recipients developed a primary Sjögren's syndrome-like exocrinopathy without signs of kidney disease. At long-term follow-up, 7(1/2) months after cell transfer, lymph nodes were enlarged, and spleens were diminished and irregular in shape. In general, changes in haematopoietic organs were more prominent in males. The results verify that although hybrid mice of either sex develop glandular manifestations comparable with primary Sjögren's syndrome, when the immune system is stimulated by semiallogeneic immunocytes, the evoked reactions in haematopoietic tissues show gender difference.

Essential fatty acid status in cell membranes and plasma of patients with primary Sjogren's syndrome. Correlations to clinical and immunologic variables using a new model for classification and assessment of disease manifestations

In 41 primary Sjögren's syndrome patients we compared fatty acid levels within erythrocyte phospholipids, plasma phospholipids, plasma triglycerides and plasma cholesterol esters, with the immunopathological and clinical disease status. Docosahexaenoic acid was the essential fatty acid (EFA), the levels of which correlated (inversely) most closely with the clinical disease status (r=-0.33 to -0.50). Levels of dihomogammalinolenic acid and eicosapentaenoic acid correlated inversely to levels of IgM rheumatoid factors (r=-0.33) and anti-SSA/Ro antibodies (r=-0.40) respectively. Moreover, levels of anti-SSA/Ro antibodies (r=-0.34-0.40) correlated with levels of the proinflammatory arachidonic acid. Sigma n-3 EFA/sigma n-6 EFA ratios correlated significantly to the quantitative estimates of immunopathological and clinical disease status. Our data are in agreement with current understanding of pro- and anti-immunoinflammatory roles within EFA metabolism, and support the rationale for intervention studies.