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Journal Article 2014; 35(Suppl 2): 197-200 PubMed PMID: 25638387 Citation  Keywords:  Antioxidants:pharmacology, Caesalpinia, Hyaluronic Acid:metabolism, Plant Extracts:pharmacology,.   

OBJECTIVES: To assess protective effects of the tara (Caesalpinia spinosa) extract against hyaluronan (HA) degradation evoked by cupric ions and ascorbate.

METHODS: Uninhibited/inhibited HA degradation was assayed by a decrease in dynamic viscosity of the HA solutions, whereas as a method rotational viscometry was used. To determine radical scavenging capacity of the tara extract, the ABTS and DPPH assays were performed.

RESULTS: The results of rotational viscometry showed remarkable protective effects of the tara extract against the degradation of HA. In the ABTS and DPPH assays the IC50 values of the tara extract 1.59 and 30.8 μg/mL indicated quite high radical scavenging properties.

CONCLUSION: The tara extract is an efficient antioxidant as demonstrated by the methods used.

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Journal Article 2014; 35(Suppl 2): 186-190 PubMed PMID: 25638386 Citation  Keywords:  Agrimonia, Antioxidants:pharmacology, Cynara, Hyaluronic Acid:metabolism, Ligustrum, Plant Preparations:pharmacology,.   

OBJECTIVES: Hyaluronan (HA) molecules were exposed to free radical-mediated degradation performed by the reaction mixture Cu(II) and ascorbate, the so-called Weissberger biogenic oxidative system, which mimics the situation of acute inflammation. To achieve protection of HA from degradation, herbal extracts such as Agrimonia herba, Cynare folium, and Ligustri folium were selected.

METHODS: Time- and dose-dependent changes of dynamic viscosity of the HA solutions in the presence and absence of the herbal extracts were recorded by rotational viscometry (RV). Radical scavenging capacity of the extracts was investigated by the spectrocolorimetric ABTS and DPPH assays.

RESULTS: The results of RV revealed that the extracts of Agrimonia herba and Cynare folium were effective in inhibiting the degradation of HA. On the other hand, the extract of Ligustri folium increased the rate of HA degradation. The highest radical scavenging capacity of ABTS(*+) and DPPH(*) was observed in Agrimonia herba extract followed by the extracts of Ligustri folium and Cynare folium.

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Journal Article 2010; 31(Suppl 2): 101-104 PubMed PMID: 21187839 Citation  Keywords:  Antioxidants:pharmacology, Ascorbic Acid:pharmacology, Copper:pharmacology, Cysteamine:pharmacology, Dose-Response Relationship, Drug, Glutathione:pharmacology, Hyaluronic Acid:metabolism, Hydrogen Peroxide:metabolism, Hydroxides:metabolism, Oxidation-Red.   

OBJECTIVE: This study presents the results of antioxidative and pro-oxidative efficacy of cysteamine and D-penicillamine (D-pen) in comparison to L-glutathione (L-GSH) on high-molar-mass hyaluronan (HA) degradation by cupric ions plus ascorbic acid.

METHODS: The substance tested was applied in the degradative system cupric ions plus ascorbate: (i) before the reaction onset or also (ii) 1 h after the reaction started. The results obtained were compared with that one recorded by using the degradative system in the absence of the substance tested. To monitor HA degradation kinetics, rotational viscometry was applied. Moreover, the standard ABTS and DPPH assays were used.

RESULTS: By using the method of rotational viscometry, D-pen showed dual effect: initial inhibitory effect on •OH radicals was changed to a pro-oxidative one in the dose and time dependent manner. Both L-GSH and cysteamine were recorded to be more effective scavengers of •OH radicals than D-pen. Cysteamine demonstrated to be an excellent scavenger also of alkoxyl- and peroxyl- type radicals. Based on IC50 values, gained by ABTS assay, it is evident that D-pen showed higher radical scavenging capacity compared to cysteamine. Similar results were observed also in DPPH assay, although in this assay less effective radical scavenging capacities of both substances tested were recorded.

CONCLUSIONS: On the basis of the results obtained, it can be stated that D-pen can produce hydrogen peroxide or •OH radicals and can inhibit the production of these oxidants. Our results showed that both L-GSH and cysteamine are similarly effective in inhibiting of HA degradation. Moreover, cysteamine demonstrated to be a significant inhibitor of alkoxyl- and peroxyl- type radicals generated from C-type macroradical of HA....

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Journal Article 2010; 31(Suppl 2): 96-100 PubMed PMID: 21187837 Citation  Keywords:  Animals, Antioxidants:pharmacology, Antirheumatic Agents:pharmacology, Arthritis, Experimental:drug therapy, Carnosine:pharmacology, Disease Models, Animal, Free Radicals, Glutathione:metabolism, Hyaluronic Acid:metabolism, In Vitro Techniques, Male, Meth.   

OBJECTIVE: New ways of supplementary or combinatory therapy of rheumatoid arthritis (RA) are of great importance. The aim is to find an additive to classical RA therapy with natural molecules without side effects possessing anti-inflammatory and anti-oxidative properties. In this study we investigated the anti-oxidative and anti-inflammatory properties of the endogenous natural compound carnosine (CARN) in vitro and in vivo. Moreover, we tested also the inhibitory properties of the drug methotrexate (MTX) on dynamic viscosity of hyaluronan (HA) solutions in the same manner.

METHODS: For in vitro testing of the inhibitory properties of CARN against degradation of HA solutions, we used the model of degradation of hyaluronan (HA) induced by free radicals. Both substances, CARN and MTX, were compared to glutathione (GSH). Rotational viscometry was used in evaluation of protective properties of compounds studied. The ability of CARN to restore the redox imbalance occurring in adjuvant arthritis (AA) of rats was also tested. We monitored the effect of CARN on hind paw volume (HPV) and on the levels of protein carbonyls, and thiobarbituric acid reacting substances (TBARS) in AA.

RESULTS: In the reaction system with the prevalence of •OH and/or peroxy-type radicals, CARN in 200 μmol/L concentration tested was shown to exert a protective action on HA degradation. MTX was less effective than CARN in preventing HA degradation. Its ability to protect HA against radical degradation was evident only at the highest concentration of 400 μmol/L. In AA, carnosine significantly reduced TBARS and protein carbonyls in plasma, and also decreased the HPV of animals most effectively on the day 14.

CONCLUSIONS: CARN proved its inhibitory properties against degradation of HA solutions at experimental conditions in vitro and showed its beneficial efficiency in vivo. Moreover, it reduced also HPV, the clinical marker of inflammation in AA....

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