1.
Heyman, Lovisa
(författare)
Berries in Prevention of Metabolic Disease – focus on obesity, diabetes and gut microbiota
2015
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The increasing prevalence of obesity is a worldwide health problem closely linked to diet and lifestyle factors. Obesity is associated with increased risk of several metabolic disorders including insulin resistance, nonalcoholic fatty liver disease and type 2 diabetes. Hence, there is a great need to identify dietary strategies for the prevention of obesity and related diseases. This thesis investigates the potential of different berries to mediate beneficial health effects in a mouse model of diet-induced obesity and prediabetes. We found that supplementation with lingonberries, blackcurrants and bilberries reduced body weight gain, insulin resistance, low-grade inflammation and hepatic lipid accumulation in C57BL/6J mice fed a high-fat diet. Supplementation with raspberries, crowberries, blackberries or prunes had no or small effects, whereas açai berries promoted development of obesity and fatty liver compared to the control group receiving high-fat diet without berries. Global hepatic gene expression analysis revealed that the phenotype in the lingonberry and bilberry groups was coupled to an anti-inflammatory effect, including downregulation of acute-phase proteins and inflammatory mediators. Mice receiving açai displayed an upregulation of steatosis markers and genes related to lipid synthesis, in line with the exacerbation of high-fat-induced fatty liver in these mice. The HELP-tagging assay was used to identify differentially methylated CpG sites in the lingonberry group compared to the high-fat control group. Lingonberries induced genome-wide and specific alterations of DNA methylation, however the significance of these findings remains to be established. Furthermore, different batches of lingonberries were found to have different capacity to prevent obesity. However lingonberries prevented low-grade inflammation, metabolic endotoxemia and modified the gut microbiota of high-fat fed mice, including increasing the Firmicutes/Bacteroidetes ratio. These findings were independent of effects on body weight gain and achieved regardless of the source of berries. The capacity of lingonberries to counteract negative outcomes of an unhealthy diet should be further evaluated in humans, including assessment of anti-inflammation and microbiota modulation. The generated knowledge about berries and their effects on metabolism may be useful in designing future dietary strategies aimed at preventing metabolic disease.
2.
Eklund, Erik, et al.
(författare)
Proteoglycan production in disomic and trisomy 7-carrying human synovial cells.
2002
Ingår i: Matrix Biology. - 1569-1802. ; 21:4, s. 325-335
Tidskriftsartikel (refereegranskat) abstract
To gain further insight into the synthesis and structure of the synovial matrix of joints, we have established cell cultures from synovial specimens and elaborated their production of hyaluronan and proteoglycans. The cultures secreted mainly the small proteoglycan decorin, but also considerable amounts of the related biglycan and the large proteoglycan versican. Only minor amounts of heparan sulfate proteoglycans were found. All cultures also had a high production of hyaluronan, which highlights the important role for normal joint function of these cells. In joint diseases, a common feature is the presence of an extra chromosome 7 (trisomy 7) in the synovial cells. To study the possible consequences of trisomy 7 on the synovial cell function, we extended our study to cultures that had been sub-cloned to contain high amounts of trisomy 7-carrying cells. These cell cultures had approximately four times more versican than their disomic counterparts in the cell culture medium, indicating that versican may be a mediator in the processes of joint destructive disorders. To find an explanation for this increase in versican, we investigated the expression/secretion of PDGF-AA and IL-6, cytokines with their genes located to chromosome 7. Indeed, both these cytokines were increased in the cultures with high frequencies of trisomy 7. We then added the two cytokines to cell cultures of disomic synovial cells, but only cells treated with IL-6 displayed an increased amount of versican. Thus, we suggest that the increased amount of versican in cultures of trisomy 7-carrying cells relates to an autocrine loop involving an increased IL-6 production.
3.
Pesonen, Erkki, et al.
(författare)
Elevated infection parameters and infection symptoms predict an acute coronary event.
2008
Ingår i: Therapeutic Advances in Cardiovascular Disease. - : SAGE Publications. - 1753-9447 .- 1753-9455. ; 2:6, s. 419-424
Tidskriftsartikel (refereegranskat) abstract
BACKGROUND: The etiology and significance of flu-like symptoms often appearing before myocardial infarction should be clarified. METHODS: In a case-control study of 323 matched controls and a random sample of 110 out of 351 cases the presence of infection symptoms during the preceding four weeks before admission were asked and blood samples taken. RESULTS: Enterovirus (EV), herpes simplex virus (HSV), and Chlamydia pneumoniae IgA titers were significantly higher in cases than in controls (p<0.001, 0.008 and 0.046, respectively). Flu-like symptoms appeared significantly more often in patients than in controls the most common one being fatigue (p<0.001). In controls with fatigue, EV and HSV titers showed a trend to be higher (1.50 vs 1.45 and 4.29 vs 3.73) than in controls without fatigue but only HSV titers were statistically significantly higher (3.47 vs 3.96, p = 0.02). Even CRP and amyloid A concentrations (3.49 vs 2.08, p<0.0001 and 5.70 vs 3.77 mg/l, p = 0.003, respectively) as well as C4 (0.40 vs 0.44, p = 0.02) were higher in controls with fatigue. CONCLUSIONS: Odds ratios for a coronary event in a logistic regression model were 4.79 for fatigue and 2.72 for EV antibody levels in their fourth quartile. A linear-by-linear association test showed increasing number of single symptoms with higher EV titer quartiles (p = 0.004).
4.
5.
6.
7.
Nowroozalizadeh, Salma, et al.
(författare)
Short-term HIV-1 treatment interruption is associated with dysregulated TLR-stimuli responsiveness.
2013
Ingår i: Human Vaccines & Immunotherapeutics. - : Informa UK Limited. - 2164-5515 .- 2164-554X. ; 9:10, s. 2103-2110
Tidskriftsartikel (refereegranskat) abstract
Viremia during human immunodeficiency virus type-1 (HIV-1) infection results in progressive impairment of several components of the immune system. Here a unique model of repeated treatment interruptions (TIs) was used with the aim to reveal the effect of controlled short-term viremia on innate stimuli responsiveness and circulating dendritic cells (DCs). Sequential peripheral blood samples from HIV-1-infected patients on combination antiretroviral therapy, subjected to repeated TI cycles as part of a therapeutic DNA vaccination study, were analyzed. In vitro responsiveness of peripheral blood mononuclear cells to toll-like receptor (TLR) stimuli was analyzed by cytokine secretion, and frequencies of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) were monitored by flow cytometry. These parameters were found not to be significantly different between the vaccinated and placebo groups. Instead, independent of vaccination altered in vitro TLR responsiveness was observed in parallel with TI cycles. TLR7/8-triggered secretion of IL-12 and IFN-α, as well as TLR9-triggered secretion of IL-12, was hyperactivated. In contrast, expression of IFN-α after TLR9 stimulation decreased during the initial cycle of TI. Reduced frequencies of pDCs and mDCs, compared with baseline, were noted before and during the second TI, respectively. Furthermore, spontaneous ex vivo release of IL-12 from PBMC was noted during cycles of TI. In conclusion, these results suggest that consequences of short-term TI include dysregulated TLR responses and fluctuations in the frequencies of circulating DCs. Knowledge of these immunological factors may influence the continuation of stringent treatment schedules during HIV infections.
8.
9.
Linga-Reddy, M. V. Prasad, et al.
(författare)
A polymorphic variant in the MHC2TA gene is not associated with systemic lupus erythematosus
2007
Ingår i: Tissue Antigens. - : Wiley. - 0001-2815 .- 1399-0039. ; 70:5, s. 412-414
Tidskriftsartikel (refereegranskat) abstract
Single-nucleotide polymorphisms (SNPs) in the major histocompatibility complex class II transactivator (MHC2TA) gene encoding the class II transactivator have been associated with multiple sclerosis, rheumatoid arthritis, and myocardial infarction in the Swedish population. We used a case-control approach to investigate the prevalence of a relevant variant in Swedish systemic lupus erythematosus (SLE) cohorts to determine whether SLE shares the same MHC2TA susceptibility allele as the other diseases. No differences were observed between cases and control subjects at either the allele or genotype levels. Furthermore, no significant correlations were found when comparing different clinical and serological SLE phenotypes. This particular polymorphism rs3087456 of the MHC2TA gene does not appear to influence genetic susceptibility to SLE in the Swedish population. We conclude that our data support neither allelic nor genotype association between the MHC2TA SNP and SLE.
10.
Prokunina, Ludmila, et al.
(författare)
A regulatory polymorphism in PDCD1 is associated with susceptibility to systemic lupus erythematosus in humans
2002
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 32:4, s. 666-669
Recension (övrigt vetenskapligt/konstnärligt) abstract
Systemic lupus erythematosus (SLE, OMIM 152700) is a complex autoimmune disease that affects 0.05% of the Western population, predominantly women. A number of susceptibility loci for SLE have been suggested in different populations, but the nature of the susceptibility genes and mutations is yet to be identified. We previously reported a susceptibility locus (SLEB2) for Nordic multi-case families. Within this locus, the programmed cell death 1 gene (PDCD1, also called PD-1) was considered the strongest candidate for association with the disease. Here, we analyzed 2,510 individuals, including members of five independent sets of families as well as unrelated individuals affected with SLE, for single-nucleotide polymorphisms (SNPs) that we identified in PDCD1. We show that one intronic SNP in PDCD1 is associated with development of SLE in Europeans (found in 12% of affected individuals versus 5% of controls; P = 0.00001, r.r. (relative risk) = 2.6) and Mexicans (found in 7% of affected individuals versus 2% of controls; P = 0.0009, r.r. = 3.5). The associated allele of this SNP alters a binding site for the runt-related transcription factor 1 (RUNX1, also called AML1) located in an intronic enhancer, suggesting a mechanism through which it can contribute to the development of SLE in humans.
