Acetylcholinesterase inhibitory activities of some flavonoids from the root bark of Pinus krempfii Lecomte: in vitro and in silico study

From the root bark of Pinus krempfii Lecomte, four flavonoids were isolated and evaluated for their inhibitory activities against AChE and BChE enzymes in vitro and in silico. Tectochrysin (1) was found to inhibit AChE with an IC50 value of 33.69 ± 2.80 μM. The docking study results also showed agreement with the in vitro test results. All four compounds also showed the best binding affinity for the AChE enzyme, characterised by binding energy (ΔG) values as low as -8.1 to -9.3 kcal/mol, in which, the compound tectochrysin had the best binding affinity for the AChE protein with a ΔG value of -9.329 kcal/mol. Tectochrysin (1) was also bound to the amino acid Phe295 of AChE with a bond length of 2.8 Å, similar to the control dihydrotanshinone-I. Galangin (2) also showed its in vitro inhibitory activity against BChE with an IC50 value of 82.21 ± 2.70 μM. In silico, it also had the best binding energy value of -9.072 kcal/mol with BChE and formed hydrogen bonds with the His438 (2.85 Å) residues of BChE like the positive control (tacrine). The steered molecular dynamics (SMD) simulation results of these two complexes revealed a mechanistic insight that the protein-ligand complexes showed stable trajectories throughout the 20 and 150 ns simulations. Moreover, the drug likeliness suggested that both flavonoids (1 and 2) were expected to be drug-like and have an LD50 toxicity level of 5. This study has contributed new results for drug discovery and the development of substances with neuroprotective effects, especially for the treatment of Alzheimer's disease.Communicated by Ramaswamy H. Sarma.

Rhodiola rosea L. Extract, a Known Adaptogen, Evaluated in Experimental Arthritis

Rhodiola rosea L. extract (RSE) is mostly known for its adaptogen properties, but not for its antiarthritic activities, therefore monotherapy and combination with low-dose methotrexate (MTX) was studied. The collagen-induced arthritis (CIA) model was used to measure the functional score, and the change in hind paw volume (HPV). Both parameters had significant antiarthritic effects. Based on these preliminary results, an adjuvant arthritis (AA) model was further applied to assess another parameters. The experiment included these animal groups: healthy controls, untreated AA, AA administered with RSE (150 mg/kg b.w. daily, p.o.), AA administered by MTX (0.3 mg/kg b.w. twice a week, p.o.), and AA treated with the combination of RSE+MTX. The combination of RSE+MTX significantly reduced the HPV and increased the body weight. The combination significantly decreased HPV when compared to MTX monotherapy. The plasmatic levels of inflammatory markers (IL-6, IL-17A, MMP-9 and CRP) were significantly decreased by MTX+RSE treatment. The RSE monotherapy didn't influence any of the inflammatory parameters studied. In CIA, the RSE monotherapy significantly decreased the arthritic parameters studied. In summary, the combination of RSE and sub-therapeutic MTX was significantly effective in AA by improving inflammatory and arthritic parameters.

Hyperbilirubinemia decreases physiological markers in adjuvant-induced arthritis

There is evidence that a higher serum level of bilirubin (BIL) may be a protective factor for autoimmune diseases. We examined the effect of BIL supplementation in adjuvant-induced arthritis (AIA) where oxidative stress, inflammation and inadequate immune response are present. Male Lewis rats were randomized into groups: CO - control, AIA - untreated adjuvant-induced arthritis, AIA-BIL - adjuvant-induced arthritis administrated BIL (200 mg/kg b.w. daily i.p. during 14 days). Change of hind paw volume in the AIA-BIL group in comparison to the AIA group was significantly decreased after BIL administration. In CO and AIA groups we found almost untraceable levels of BIL. In the AIA-BIL group hyperbilirubinemia was observed. BIL administration significantly decreased plasma levels of C-reactive protein and ceruloplasmin in the AIA-BIL group in comparison to the AIA group. The values of white and red blood cells, hemoglobin and hematocrit were significantly decreased in AIA-BIL after BIL supplementation. Organs like spleen and thymus had a lower weight in AIA-BIL than in AIA. Histological findings showed decreased or even absent damage in hind paw joint of AIA-BIL animals. We observed an immunomodulatory effect of BIL on AIA development, which may also have a novel pharmacological impact.

Markers of inflammation and oxidative stress studied in adjuvant-induced arthritis in the rat on systemic and local level affected by pinosylvin and methotrexate and their combination

Oxidative stress (OS) is important in the pathogenesis of autoimmune diseases such as rheumatoid arthritis (RA) and its experimental model--adjuvant arthritis (AA). Antioxidants are scarcely studied in autoimmunity, and future analyses are needed to assess its effects in ameliorating these diseases. Although there are studies about antioxidants effects on the course of RA, their role in combination therapy has not yet been studied in detail, especially on extra-articular manifestations of AA. During the 28-d administration of pinosylvin (PIN) in monotherapy and in combination with methotrexate (MTX) to AA rats, we evaluated the impact of the treatment on selected parameters. The experiment included: healthy controls, untreated AA, AA administered 50 mg/kg b.w. of PIN daily p.o., AA administered 0.4 mg/kg b.w. of MTX twice weekly p.o. and AA treated with a combination of PIN+MTX. AA was monitored using: hind paw volume, C-reactive protein, monocyte chemotactic protein-1 (MCP-1), thiobarbituric acid reactive substances (TBARS) and F2-isoprostanes in plasma, γ-glutamyltransferase activity in spleen, activity of lipoxygenase (LOX) in lung, heme oxygenase-1 (HO-1) and nuclear factor kappa B (NF-κB) in liver and lung. PIN monotherapy significantly improved the activation of NF-κB in liver and lung, HO-1 expression and activity of LOX in the lung, MCP-1 levels in plasma (on 14th d) and plasmatic levels of F2-isoprostanes. An important contribution of PIN to MTX effect was the reduction of OS (an increase of HO-1 expression in lung and reduction of plasmatic TBARS) and decrease of LOX activity in the lung.

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.

Combined methotrexate and coenzyme Q₁₀ therapy in adjuvant-induced arthritis evaluated using parameters of inflammation and oxidative stress

Rheumatoid arthritis is a common severe joint disease that affects all age groups, it is thus of great importance to develop new strategies for its treatment. The aim of the present study was to examine the combined effect of coenzyme Q₁₀ (CoQ₁₀) and methotrexate (MTX) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis (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 CoQ₁₀, with methotrexate, and with a combination of CoQ₁₀ and methotrexate. The two latter groups received a daily oral dose of 20 mg/kg b.w. of CoQ₁₀, either alone or with methotrexate in an oral dose of 0.3 mg/kg b.w. twice a week. We found that CoQ₁₀ potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect of methotrexate on the level of oxidation of proteins (suppression of protein carbonyl level in plasma) as well as lipoperoxidation (suppression of levels of HNE-adducts and MDA-adducts to plasma proteins). The same effect was observed for plasmatic levels of CoQ₉ and IL-1α, and partially also for γ-glutamyltransferase activity assessed in joints and spleen. Moreover, the combination therapy improved the functionality of peripheral blood neutrophils in AA, with a balancing effect on the immunosuppression caused by MTX monotherapy. In summary, combined administration of CoQ₁₀ and methotrexate suppressed arthritic progression in rats more effectively than did MTX alone. This finding may help improve treatment of rheumatoid arthritis.

Combined methotrexate and coenzyme Q₁₀ therapy in adjuvant-induced arthritis evaluated using parameters of inflammation and oxidative stress

Rheumatoid arthritis is a common severe joint disease that affects all age groups, it is thus of great importance to develop new strategies for its treatment. The aim of the present study was to examine the combined effect of coenzyme Q₁₀ (CoQ₁₀) and methotrexate (MTX) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis (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 CoQ₁₀, with methotrexate, and with a combination of CoQ₁₀ and methotrexate. The two latter groups received a daily oral dose of 20 mg/kg b.w. of CoQ₁₀, either alone or with methotrexate in an oral dose of 0.3 mg/kg b.w. twice a week. We found that CoQ₁₀ potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect of methotrexate on the level of oxidation of proteins (suppression of protein carbonyl level in plasma) as well as lipoperoxidation (suppression of levels of HNE-adducts and MDA-adducts to plasma proteins). The same effect was observed for plasmatic levels of CoQ₉ and IL-1α, and partially also for γ-glutamyltransferase activity assessed in joints and spleen. Moreover, the combination therapy improved the functionality of peripheral blood neutrophils in AA, with a balancing effect on the immunosuppression caused by MTX monotherapy. In summary, combined administration of CoQ₁₀ and methotrexate suppressed arthritic progression in rats more effectively than did MTX alone. This finding may help improve treatment of rheumatoid arthritis.

Formation of reactive oxygen and nitrogen species in the presence of pinosylvin - an analogue of resveratrol

OBJECTIVE

Formation of reactive oxygen species in neutrophils of rats with adjuvant arthritis and generation of nitric oxide in RAW 264.7 macrophages were analysed in the presence of pinosylvin.

METHODS AND RESULTS

The method of chemiluminescence was used for the detection of reactive oxygen species in blood of rats with adjuvant arthritis. Pinosylvin (50 mg/kg, daily, p.o.) and methotrexate (0.4 mg/kg, twice a week, p.o.) were applied separately or in a combination over a period of 28 days from the day of immunisation. Adjuvant arthritis was accompanied by a significantly increased number of neutrophils, by elevated concentration of oxidants in blood and by excessive responsiveness of neutrophils to stimulation with PMA. In rats treated with methotrexate, all these changes were significantly reduced and the inhibition became more pronounced when methotrexate was applied in the combination with pinosylvin; the monotherapy with pinosylvin did not induce any detectable changes in the parameters tested. Under in vitro conditions, pinosylvin inhibited formation of nitric oxide (NO) in macrophages, as demonstrated by the decreased concentration of nitrite - the end-product of NO metabolism (assessed by Griess' method), by the reduced expression of inducible NO synthase (detected by Western blot), and by the failure of pinosylvin to scavenge nitric oxide (measured amperometrically in cell-free system).

CONCLUSION

The observed ability of pinosylvin to decrease concentration of reactive oxygen and nitrogen species, along with its capacity to enhance the efficacy of methotrexate in arthritis treatment may shed more light into the pharmacological potential of this prospective natural substance.

In vivo effect of pinosylvin and pterostilbene in the animal model of adjuvant arthritis

OBJECTIVE

The aim of this study was to evaluate the effects of pinosylvin (PIN) and pterostilbene (PTE), natural substances from the stilbenoid group, on the development of adjuvant arthritis in rats.

METHODS

Adjuvant arthritis (AA) was induced by a single intradermal injection of Mycobacterium butyricum in incomplete Freund's adjuvant in male Lewis rats. Our experiments included healthy intact animals as reference controls, arthritic animals without any drug administration, and arthritic animals with administration of PIN and PTE in the oral daily dose of 30 mg/kg b.w. The treatment involved administration of the substances tested from day 0, i.e. the day of immunization, to the experimental day 28. The following parameters were monitored: change of the hind paw volume (HPV) on day 14, 21 and 28, luminol-enhanced chemiluminescence (CL) of the joint and myeloperoxidase (MPO) activity in hind paw joint homogenates (day 28).

RESULTS

Arthritic animals treated with PIN showed a decrease in HPV, significantly on days 14 and 28. PIN decreased CL of the joint as well as MPO activity of the joint homogenate, in comparison with untreated animals. PTE had no effect on HPV and MPO activity in hind paw joint homogenates and exerted only a partial effect on luminol-enhanced CL.

CONCLUSIONS

On the basis of our results we conclude that the effect of PTE on CL was only partial. PIN, on the other hand, had a beneficial anti-inflammatory and antioxidant effect on oxidative stress induced biochemical changes occurring in AA, as determined by all three functional parameters.

Carnosine inhibits degradation of hyaluronan induced by free radical processes in vitro and improves the redox imbalance in adjuvant arthritis in vivo

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.

Ascorbate and Cu(II)-induced oxidative degradation of high-molar-mass hyaluronan. Pro- and antioxidative effects of some thiols

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.

Modulation of SERCA in the chronic phase of adjuvant arthritis as a possible adaptation mechanism of redox imbalance

Adjuvant arthritis (AA) is a condition that involves systemic oxidative stress. Unexpectedly, it was found that sarcoplasmic reticulum Ca(2 +)-ATPase (SERCA) activity was elevated in muscles of rats with AA compared to controls, suggesting possible conformational changes in the enzyme. There was no alteration in the nucleotide binding site but rather in the transmembrane domain according to the tryptophan polar/non-polar fluorescence ratio. Higher relative expression of SERCA, higher content of nitrotyrosine but no increase in phospholipid oxidation in AA SR was found. In vitro treatments of SR with HOCl showed that in AA animals SERCA activity was more susceptible to oxidative stress, but SR phospholipids were more resistant and SERCA could also be activated by phosphatidic acid. It was concluded that increased SERCA activity in AA was due to increased levels of SERCA protein and structural changes to the protein, probably induced by direct and specific oxidation involving reactive nitrogen species.

Effects of sesame oil in the model of adjuvant arthritis

OBJECTIVES

The goal of this study was to evaluate the effect of sesame oil on functional damage induced by adjuvant arthritis (AA) and on changes of selected biochemical parameters reflecting oxidative tissue injury.

DESIGN

Mycobacterium butyricum in incomplete Freund's adjuvans was intradermally administered to Lewis male rats. Hind paw edema and endothelium-dependent relaxation of the aorta were determined on day 28. Further, plasmatic levels of TBARS, gamma-glutamyltransferase (GGT) activity in the joint and spleen tissues, level of protein carbonyls and total antioxidant capacity (TAC) in plasma, as well as activity of the lysosomal enzyme N-acetyl-glucosaminidase (NAGA) in serum were assessed. The effect of sesame oil (SO, 1ml/kg, daily oral administration) was evaluated on day 28.

RESULTS

The beneficial effect of sesame oil on markers of oxidative stress accompanying AA was demonstrated by decrease of plasma TBARS and decrease of GGT activity in the joint and spleen tissues. Level of protein carbonyls, TAC in plasma and activity of NAGA in serum and in the kidney were improved, yet not significantly. In the hind paw edema the maximal increase was found on day 28 of AA, and in the same time we observed a significant decrease of aortic endothelium-dependent relaxation. Administration of SO resulted in mild, non-significant decrease of hind paw swelling and in significantly increased acetylcholine-evoked relaxation.

CONCLUSION

We conclude that SO has beneficial effects on oxidative stress induced biochemical changes occurring in AA, moreover it improves endothelium-dependent relaxation of the aorta and tends to decrease hind paw edema.

Oxidative impairment of plasma and skeletal muscle sarcoplasmic reticulum in rats with adjuvant arthritis - effects of pyridoindole antioxidants

OBJECTIVES

To study possible oxidation of proteins and lipids in plasma and sarcoplasmic reticulum (SR) from skeletal muscles and to assess the effects of pyridoindole antioxidants in rats with adjuvant arthritis (AA) and to analyze modulation of Ca-ATPase activity from SR (SERCA).

METHODS

SR was isolated by ultracentrifugation, protein carbonyls in plasma and SR were determined by ELISA. Lipid peroxidation was analyzed by TBARS determination and by mass spectrometry. ATPase activity of SERCA was measured by NADH-coupled enzyme assay. Tryptophan fluorescence was used to analyze conformational alterations.

RESULTS

Increase of protein carbonyls and lipid peroxidation was observed in plasma of rats with adjuvant arthritis. Pyridoindole antioxidant stobadine and its methylated derivative SMe1 decreased protein carbonyl formation in plasma, effect of stobadine was significant. Lipid peroxidation of plasma was without any effect of pyridoindole derivatives. Neither protein oxidation nor lipid peroxidation was identified in SR from AA rats. SERCA activity from AA rats increased significantly, stobadine and SMe1 diminished enzyme activity. Ratio of tryptophan fluorescence intensity in SR of AA rats increased and was not influenced by antioxidants.

CONCLUSION

Plasma proteins and lipids were oxidatively injured in rats with AA; antioxidants exerted protection only with respect to proteins. In SR, SERCA activity was altered, apparently induced by its conformational changes, as supported by study of tryptophan fluorescence. Stobadine and SMe1 induced a decrease of SERCA activity, elevated in AA rats, but they did not affect conformational changes associated with tryptophan fluorescence.

Glucomannan in prevention of oxidative stress and inflammation occurring in adjuvant arthritis

OBJECTIVES

The aim of this study was to evaluate the effects of a biological response modifier, glucomannan (GM), isolated from Candida utilis, on the progress of adjuvant arthritis in Lewis rats.

METHODS

Adjuvant arthrithis was induced in Lewis rats by a single intradermal injection of Mycobacterium butyricum. GM was administered in two different doses of 5 and 7.5 mg/kg b.w. The treatment involved daily oral or intraperitoneal administration of the substance from day 0, i.e. the day of immunization to the end of the experiment - day 28. Cyclosporin A was used as a therapeutic standard in daily oral dose of 2.5 mg/kg b.w. The following parameters were monitored: hind paw volume, total antioxidant status, protein carbonyl groups, activity of N-acetyl-beta-D-glucosaminidase in plasma, lysozyme and peroxidase activity of peritoneal macrophages and activity of gamma-glutamyltransferase in homogenates of spleen, hind paw muscle and hind paw joint.

RESULTS

Beneficial action of GM was revealed mainly in hind paw volume decrease. Further decrease of the activity of the enzyme gamma glutamyltransferase (GGT) in the spleen, hind paw joint and muscle tissue homogenates, decrease of the plasmatic activity of N-acetyl-beta-D-glucosaminidase (NAGA), and finally suppression of lysozyme and peroxidase activity assessed in peritoneal macrophages were observed in arthritic animals treated with GM. All these findings speak in favor of the anti-inflammatory activity of glucomannan. Moreover, a significant improvement of the arthritis induced suppression of total antioxidant status and decrease of the level of the arthritis-associated protein carbonyls in plasma were detected.

CONCLUSIONS

The important characteristics of GM isolated from Candida utilis, such as good water solubility and relatively small molecular weight, along with the observed in vivo anti-inflammatory and antioxidant effects, appear to be promising features for its prospective use as a natural agent in prevention and supplementary therapy of rheumatoid arthritis.

Effect of coenzyme Q(10) supplementation in the rat model of adjuvant arthritis

Adjuvant arthritis (AA) is a model of chronic inflammation induced by Mycobacterium butyricum and characterized by similar pathophysiological and pathobiochemical changes as rheumatoid arthritis (RA) in humans. In this study the antirheumatic activity of coenzyme Q(10) supplementation was tested not only as to its capability to suppress the inflammation edema of the hind paw and to improve the body weight of the arthritic animals, but also to improve so important biochemical parameters as markers of inflammation and oxidative stress, and of mitochondrial bioenergetics. Despite the unfavorable effects on the rheumatic processes observed by monitoring biometric parameters (hind paw volume, relative body weight, relative weight of spleen), a significant protective effect was observed on the level of mitochondrial energetic and antioxidant disbalance. This finding speaks in favor of CoQ(10) supplementation in rheumatic patients, presumably as combinatory therapy with classical antirheumatics, e.g. NSAIDs.

Values of markers of early and advanced glycation and lipoxidation in serum proteins of children with diabetes mellitus

BACKGROUND

Advanced glycation endproducts (AGEs) have been established as one of the major factors responsible for the multi-organ damage seen in diabetes. AGEs and lipoxidation products, as e.g. MDA, and their adducts with proteins appear to be formed together in serum and tissues. A link between AGEs formation and increased lipoxidation at tissue damage is under investigation.

AIM

The aim of the present study was to determine fructosamine (FAM), glycated haemoglobin (HbA1c) AGEs-specific fluorescence and MDA-protein adducts specific fluorescence in diabetic and in healthy children, with statistical evaluation of the relationship between the parameters assessed.

SUBJECTS AND METHODS

Values of FAM and HbA1c (spectrophotometry) and of AGEs-specific fluorescence and MDA-protein adducts specific fluorescence were investigated in serum proteins of 17 children with poorly controlled type 1 diabetes mellitus (age range 9 to 18 years). Eight healthy children (age range 7 to 17 years) served as controls.

RESULTS

In the diabetic group, all the parameters evaluated were significantly higher than in the control group. Furthermore, MDA-linked specific fluorescence of MDA-protein adducts (a biomarker of oxidative stress) was correlated with AGEs-specific fluorescence. In patients this correlation was extremely significant (r = 0.8176, p < 0.0001).

CONCLUSION

The increased oxidative stress in children with type 1 diabetes may not be attributed to complications, though it could contribute to the development of complications. (Tab. 2, Fig. 7, Ref. 30.)