The protective effect of chondroitin sulfate on induced arthritis in rats.

The protective effect of chondroitin sulfate on induced arthritis in rats

Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis

A "Candidate-Interactome" Aggregate Analysis of Genome-Wide Association Data in Multiple Sclerosis

Though difficult, the study of gene-environment interactions in multifactorial diseases is crucial for interpreting the relevance of non-heritable factors and prevents from overlooking genetic associations with small but measurable effects. We propose a “candidate interactome” (i.e. a group of genes whose products are known to physically interact with environmental factors that may be relevant for disease pathogenesis) analysis of genome-wide association data in multiple sclerosis. We looked for statistical enrichment of associations among interactomes that, at the current state of knowledge, may be representative of gene-environment interactions of potential, uncertain or unlikely relevance for multiple sclerosis pathogenesis: Epstein-Barr virus, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, cytomegalovirus, HHV8-Kaposi sarcoma, H1N1-influenza, JC virus, human innate immunity interactome for type I interferon, autoimmune regulator, vitamin D receptor, aryl hydrocarbon receptor and a panel of proteins targeted by 70 innate immune-modulating viral open reading frames from 30 viral species. Interactomes were either obtained from the literature or were manually curated. The P values of all single nucleotide polymorphism mapping to a given interactome were obtained from the last genome-wide association study of the International Multiple Sclerosis Genetics Consortium & the Wellcome Trust Case Control Consortium, 2. The interaction between genotype and Epstein Barr virus emerges as relevant for multiple sclerosis etiology. However, in line with recent data on the coexistence of common and unique strategies used by viruses to perturb the human molecular system, also other viruses have a similar potential, though probably less relevant in epidemiological terms

A “Candidate-Interactome” Aggregate Analysis of Genome-Wide Association Data in Multiple Sclerosis

Though difficult, the study of gene-environment interactions in multifactorial diseases is crucial for interpreting the relevance of non-heritable factors and prevents from overlooking genetic associations with small but measurable effects. We propose a "candidate interactome" (i.e. a group of genes whose products are known to physically interact with environmental factors that may be relevant for disease pathogenesis) analysis of genome-wide association data in multiple sclerosis. We looked for statistical enrichment of associations among interactomes that, at the current state of knowledge, may be representative of gene-environment interactions of potential, uncertain or unlikely relevance for multiple sclerosis pathogenesis: Epstein-Barr virus, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, cytomegalovirus, HHV8-Kaposi sarcoma, H1N1-influenza, JC virus, human innate immunity interactome for type I interferon, autoimmune regulator, vitamin D receptor, aryl hydrocarbon receptor and a panel of proteins targeted by 70 innate immune-modulating viral open reading frames from 30 viral species. Interactomes were either obtained from the literature or were manually curated. The P values of all single nucleotide polymorphism mapping to a given interactome were obtained from the last genome-wide association study of the International Multiple Sclerosis Genetics Consortium & the Wellcome Trust Case Control Consortium, 2. The interaction between genotype and Epstein Barr virus emerges as relevant for multiple sclerosis etiology. However, in line with recent data on the coexistence of common and unique strategies used by viruses to perturb the human molecular system, also other viruses have a similar potential, though probably less relevant in epidemiological terms

The protective effect of chondroitin sulfate on induced arthritis in rats

The protective effect of chondroitin sulfate on induced arthritis in rat

Pinosilvin administered in monotherapy and in combination with methotrexate reduces oxidative stress in adjuvant arthritis rat model

Rheumatoid arthritis (RA) is a common severe joint disease that involves all age groups. This is one of the conditions in which oxidative stress (OS) has been shown to play a role by regulating the progression of the inflammatory response. Adjuvant arthritis (AA) is a rat model of autoimmune erosive arthritis widely used to evaluate etiopathogenetic mechanisms in RA as well as for testing anti-inflammatory drugs. Pinosylvin (PIN), 3,5-dihydroxy-trans-stilbene, is an analogue of resveratrol mainly found in the heartwood of Pinus sylvestris. The aim of the present study was to examine the eventual antioxidant and anti-inflammatory effect of PIN on the progression of AA in rats in monotherapy and in combination with methotrexate (MTX). AA was induced by a single intradermal injection of heat-inactivated Mycobacterium butyricum in incomplete Freund’s adjuvant. The experiments included healthy animals, arthritic animals not treated, arthritic animals treated with MTX, with PIN, and with a combination of PIN and MTX. The two latter groups received a daily oral dose of 50 mg/kg b.w. of PIN, either alone or with MTX in an oral dose of 0.4 mg/kg b.w. twice a week during 28 experimental days. Our data demonstrated that PIN potentiated both the anti-arthritic (decrease of hind paw volume) and the antioxidant effect of MTX (TBARS in plasma). The level of inflammatory protein CRP in plasma and activity of GGT in spleen were not improved by addition of PIN to MTX due to the prominent effect of MTX alone on these parameters. Arthritic animals showed increased OS, also evaluated as plasma levels of isoprostanes. PIN alone or in combination with MTX strongly reduced isoprostane levels (about 50%). Anti-inflammatory and antioxidant functions have been attributed to heme oxygenase (HO-1). Our data show a significant decline in HO-1 (about 40%) in the lung from AA rats. In these animals, PIN alone increased the levels of HO-1 by about 30% more than MTX. Moreover, the combination therapy was the most effective in increasing the levels of HO-1 (3-fold in respect to AA values). Finally, activated NF-B plays an important role in the expression of pro-inflammatory genes. In our model, we observed a marked increase in NF-B in the lung and liver from AA animals. This increase was strongly reduced by PIN alone as well as in combination with MTX. These results suggest that the anti-inflammatory activity of PIN can be mediated by suppression of NF-B activation. In conclusion, PIN is able to reduce OS in AA rat model. In fact, the combined administration of PIN and MTX suppressed arthritic progression more effectively than did MTX alone. This natural compound may then be useful in the treatment of rheumatoid arthritis. Acknowledgement: VEGA 2/0045/11, APVV-052-10, CNR/SAV bilateral project 2010-2012: In vitro and in vivo models of arthritic processes for studying the mechanisms of inflammation and oxidative stress link-up. New perspectives for arthritis therapy. Pinosylvin used in this study was prepared by Prof. Jan Šmidrkal (Institute of Chemical Technology, Prague, Czech Republic) and Ing. Juraj Harmatha, PhD (Institute of Organic Chemistry and Biochemistry, Academy of Sciences of Czech Republic)

Chondroitin Sulfate Effect On Induced Arthritis In Rats

OBJECTIVE: Rodent models of osteoarthritis and rheumatoid arthritis are useful tools to study these disease processes. Adjuvant arthritis (AAR) is a model of polyarthritis widely used for preclinical testing of antiarthritis substances. We report the effect of two different doses of highly purified chondroitin sulfate (CS) pharmaceutical grade in the AAR animal model after oral administration.DESIGN: AAR was induced by a single intradermal injection of heat-inactivated Mycobacterium butyricum in incomplete Freund's adjuvant. The experiments included healthy animals, untreated arthritic animals, arthritic animals having been administered 300 or 900 mg/kg of CS daily, 14 days before AAR induction until the end of the experiment (day 28), arthritic animals having been administered 300 or 900 mg/kg of CS daily, from day 1 until the end of the experiment.RESULTS: CS was capable of significantly reducing the severity of arthritis along with oxidative stress, a consequence of chronic inflammatory processes occurring in AAR. The CS pre-treatment regimen was effective throughout the whole subacute phase, while treatment from day 1 proved effective only in the chronic period. The effects were confirmed by improved total antioxidant status and γ-glutamyltransferase activity. CS administered under a pre-treatment regimen was also able to reduce the production of pro-inflammatory cytokines, C-reactive protein in plasma, phagocytic activity and the intracellular oxidative burst of neutrophils.CONCLUSIONS: CS proved to be effective in slowing down AAR development and in reducing disease markers, thus supporting its beneficial activity as a drug in humans

Effect of nonanimal high- and low-molecular-mass chondroitin sulfates produced by a biotechnological process in an animal model of polyarthritis

BACKGROUND/AIMS: We planned to report on the effect of two nonanimal chondroitin sulfates (CSs) with different molecular masses produced using an innovative biotechnological process in an adjuvant arthritis animal model. METHODS: The experiments included healthy animals, untreated arthritic animals and arthritic animals having been administered 900 mg/kg of either of the two CS samples daily. Arthritic score, γ-glutamyltransferase (GGT) activity in hind paw joint tissue homogenates, plasmatic C-reactive protein (CRP) and pro-inflammatory cytokines IL-1β and IL-6 were assayed. RESULTS AND CONCLUSIONS: Low-molecular-mass (LMM) CS significantly reduced the arthritic score by up to about 30% from 14 to 28 days. In contrast, no significant differences were observed for high-molecular-mass (HMM) CS, even if a trend in its capacity to decrease the arthritic score by up to about 11% was observed. Additionally, LMM CS was able to significantly decrease GGT activity by approximately 31% and plasmatic CRP levels by about 9%. Both nonanimal CS samples were effective in reducing plasmatic levels of proinflammatory cytokines. A greater efficacy was also observed for LMM CS compared with a pharmaceutical-grade CS of extractive origin, while the efficacy of the HMM CS sample was found to be rather similar. The greater effect of LMM CS in reducing arthritic parameters may be related to its lower molecular mass with respect to HMM CS and natural CS

Activity of pinosylvin administered in monotherapy and in combination with methotrexate on the development of rat adjuvant arthritis

Oxidative stress (OS) has been implicated in various pathological conditions involving several diseases and aging. Rheumatoid arthritis (RA) is a common severe joint disease that involves all age groups. The pathogenesis of RA is associated predominantly with the formation of free radicals at the site of inflammation. However, knowledge on the role of OS in the progression of RA is scarce and the link between OS and inflammation status in arthritis should be more precisely investigated. Pinosylvin (PIN), 3,5-dihydroxy-trans-stilbene, is mainly found in the heartwood of Pinus sylvestris. PIN used in this study was synthesized in the Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague, Czech Republic by Ing. Juraj Harmatha, PhD. The aim of the present study was to examine the effect of PIN on the progression of adjuvant-induced arthritis (AA) in rats in monotherapy and in combination with methotrexate (MTX), which is a classical immunosuppressant drug. AA was induced by a single intradermal injection of heat-inactivated Mycobacterium butyricum in incomplete Freund’s adjuvant. The experiments included healthy animals, arthritic animals not treated, arthritic animals treated with MTX, with PIN, and with a combination of PIN and MTX. The two latter groups received a daily oral dose of 50 mg/kg b.w. of PIN, either alone or with MTX in an oral dose of 0.4 mg/kg b.w. twice a week during 28 experimental days. We found that PIN potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect of MTX (reduction of plasmatic levels of TBARS). Activity of GGT in spleen, level of MCP-1 and CRP in plasma were not improved by addition of PIN to MTX due to the prominent effect of MTX alone on these parameters. Arthritic animals showed increased OS, evaluated as plasma levels of isoprostanes. PIN alone or in combination with MTX strongly reduced isoprostane levels (about 50%). On the contrary, a significant decline in Nrf2-regulated antioxidant defences, such as hemeoxygenase-1 (HO-1), was observed in the lung (about 40%) but not in the liver from AA rats. In the AA lung, PIN alone increased the levels of HO-1 by about 30% more than MTX. Moreover, the combination therapy was the most effective in increasing the levels of HO-1 (3-fold in respect to AA values). OS can also activate NF-B, which plays a critical role in the transcription of proinflammatory genes. Our data showed a marked increase in NF-B in the lung and liver from AA animals. This increase was strongly reduced by PIN alone as well as in combination with MTX. Our results suggest that the anti-inflammatory activity of PIN is mediated by suppression of NF-kB activation in the liver and lung of arthritic animals. In summary, combined administration of PIN and MTX suppressed arthritic progression in rats more effectively than did MTX alone. This natural compound is able to reduce OS in vivo and may help improve the treatment of rheumatoid arthritis. Acknowledgement: VEGA 2/0045/11, APVV-0315-07, CNR/SAV bilateral project 2010-2012: In vitro and in vivo models of arthritic processes for studying the mechanisms of inflammation and oxidative stress link-up. New perspectives for arthritis therapy