**Author details**

*Antioxidants*

assumptions.

**4. Conclusion**

of synovial fluid and reduction of lipoperoxidation not only in the synovium but also in the plasma as what we have found in our study. Also, the direct antioxidant ability of HA, which has been described, could contribute to the reduction of lipoperoxidation [55]. However, further studies need to be made to confirm these

New treatment strategies based on blockade of cytokine pathways in late stages

In our study, we have shown the ability of per orally administered HA to improve

the antioxidant defense (SOD, GPx, and total antioxidant capacity of plasma). This therapeutic effect of HA could be a result of direct (intestinal absorption) and indirect (intestinal cell immunomodulatory) anti-inflammatory activities. Recent results have shown that dietary high-molecular-weight HA can be distributed to connective tissues. Dietary HA could be beneficial for joints, knee pain, relief of synovial effusion, or inflammation and improvement of muscular knee strength. HA also binds to toll-like receptor-4 (TLR4) in the luminal surface of the large intestine resulting in the downregulation of systemic proinflammatory cytokines. However, further research is needed with endogenous antioxidants, mainly human studies, in order to establish an antioxidative treatment approach in inflam-

The experiments were supported by APVV-15-0308, VEGA 2/0044/15, and VEGA 2/0115/19. In the experiment realization, Danica Mihalova, Jana Urgosova, Frantisek Drafi, Martina Horvathova, Kristina Farkasova, Anna Gvozdjakova, Olga Vancova, and Olga Ulicna were involved. Hyaluronan samples were purchased by cofounder and current CEO Vladimir Velebny (Contipro, Czech Republic). Thanks

to Miloslav Zloh for the technical assistance in manuscript preparation.

The authors declare that they do not have any conflict of interest.

of RA are progressing. In spite of their benefits, long-time utilization of these blocking agents has indicated side effects. The antioxidant defense system includes endogenous (enzymatic and nonenzymatic) and exogenous (dietary) antioxidants that interact in establishing redox homeostasis in the body. Therapeutic benefits from antioxidant treatment are primarily bound to reduction of systemic OS. CoQ10 treatment significantly improved concentrations of the investigated endogenous antioxidants (CoQ9-total, CoQ10-total, and gamma tocopherol in plasma). CoQ10 for its bioenergetic, antioxidant, and anti-inflammatory properties might be therapeutically useful for a long-term supplementary administration to

patients with inflammatory diseases such as RA.

matory-based diseases such as RA.

**Acknowledgements**

**Conflict of interest**

**164**

Katarina Bauerova1,2,\*, Jarmila Kucharska3 , Silvester Ponist1 , Lukas Slovak1 , Karol Svik1 , Vladimir Jakus3 and Jana Muchova3

1 Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovakia

2 Faculty of Pharmacy, Comenius University, Bratislava, Slovakia

3 Faculty of Medicine, Comenius University, Bratislava, Slovakia

\*Address all correspondence to: katarina.bauerova@savba.sk

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
