Polyamine analogue QMA attenuated ischemic injury in MCAO rats via ERK and Akt activated Nrf2/HO-1 signaling pathway.

Previous research showed N1-(quinolin-2-ylmethy) butane-1, 4-diamine (QMA), a polyamine analogue, was efficacious in the prevention of oxidative injury in models of cerebral ischemia. The present study manifested that pretreatment with QMA attenuated ischemic damage accompanying up regulation of Nuclear factor erythroid 2­related factor (Nrf2), Heme oxygenase­1 (HO­1), p-ERK and p-Akt in cerebral cortex tissues of middle cerebral artery occlusion (MCAO) rats and oxygen-glucose deprivation (OGD)-treated PC12 cells. Further more, treatment with LY294002 (specific PI3K inhibitor), PD98059 (specific ERK inhibitor), brusatol (specific Nrf2 inhibitor) and SnPP (specific HO-1 inhibitor) deprived almost all the effects of QMA in MCAO rats and OGD-treated PC12 cells. These data suggested that the protective actions of QMA on the cerebral ischemia may be related to activation of endogenous cytoprotective mechanism via ERK and Akt activated Nrf2/HO-1 signaling pathway.

Long-Term Alteration of Reactive Oxygen Species Led to Multidrug Resistance in MCF-7 Cells.

Reactive oxygen species (ROS) play an important role in multidrug resistance (MDR). This study aimed to investigate the effects of long-term ROS alteration on MDR in MCF-7 cells and to explore its underlying mechanism. Our study showed both long-term treatments of H2O2 and glutathione (GSH) led to MDR with suppressed iROS levels in MCF-7 cells. Moreover, the MDR cells induced by 0.1 µM H2O2 treatment for 20 weeks (MCF-7/ROS cells) had a higher viability and proliferative ability than the control MCF-7 cells. MCF-7/ROS cells also showed higher activity or content of intracellular antioxidants like glutathione peroxidase (GPx), GSH, superoxide dismutase (SOD), and catalase (CAT). Importantly, MCF-7/ROS cells were characterized by overexpression of MDR-related protein 1 (MRP1) and P-glycoprotein (P-gp), as well as their regulators NF-E2-related factor 2 (Nrf2), hypoxia-inducible factor 1 (HIF-1α), and the activation of PI3K/Akt pathway in upstream. Moreover, several typical MDR mediators, including glutathione S-transferase-π (GST-π) and c-Myc and Protein Kinase Cα (PKCα), were also found to be upregulated in MCF-7/ROS cells. Collectively, our results suggest that ROS may be critical in the generation of MDR, which may provide new insights into understanding of mechanisms of MDR.

N1-(Quinolin-2-ylmethyl) butane-1, 4-diamine, a polyamine analog: inhibition of platelet aggregation mediated by an elevated VASP, and decreased MAPK phosphorylation.

The current study intended to examine the signal transduction pathway of N-(quinolin-2-ylmethyl) butane-1, 4-diamine (QMA) in antiplatelet aggregation. Rats were divided randomly into five groups: control group; QMA-treated groups (0.3, 1, and 3 mg/kg); and r-Hirudin-treated group (0.3 mg/kg). Sample groups intravenously injected the corresponding agents once a day for 5 days; control group took 0.9% NaCl in the same way. Ten minutes after the last injection, blood samples were obtained from the rat abdominal aorta. Aggregation ex vivo was tested after irritating platelets by 1.5 U/ml thrombin for 5 min with a platelet aggregometer. Malondialdehyde production, activity of superoxide dismutase and nitric oxide production were determined by the microplate reader. Measurement of [Ca]i was performed using a fluorescence spectrophotometer. Thromboxane A2, cyclic adenosine monophosphate and cyclic guanosine monophosphate levels, vasodilator-stimulated phosphoprotein, and mitogen-activated protein kinase phosphorylation were measured with ELISA kits. Phospholipase C γ2 and protein kinase C were observed by immunoblotting study. QMA inhibited thrombin-induced platelet aggregation ex vivo. QMA significantly elevated superoxide dismutase activity, levels of cyclic adenosine monophosphate, cyclic guanosine monophosphate, nitric oxide, and subsequently promoted vasodilator-stimulated phosphoprotein phosphorylation. Meanwhile, QMA suppressed phospholipase C γ2, protein kinase C and mitogen-activated protein kinase phosphorylation, as well as malondialdehyde, thromboxane A2 formation and [Ca]i mobilization. QMA has a strong antiplatelet potential via its multitarget mechanism.

CJY, an isoflavone, interacts with ATPase of P-glycoprotein in the rat brain microvessel endothelial cells (RBMECs).

Our previous study reported CJY, an isoflavone, can reverse P-glycoprotein (P-gp) efflux activity in rat brain microvessel endothelial cells (RBMECs). In the present report, by assessment of ATPase activity of RBMECs, we gained further insight into the nature of the CJY interactions with P-gp. The results revealed that the basal P-gp ATPase activity was increased by CJY. Kinetic studies on ATPase activity showed the effects of Tetrandrine (Tet) on CJY-stimulated, CsA on CJY-stimulated, and CsA on Tet-stimulated P-gp ATPase activity were all non-competitive inhibition, indicating that these substrates can simultaneously but independently bind to diverse sites on P-gp. Furthermore, the combined effects of CJY with Tet, and CJY with CsA were also evaluated isobolographically. The results showed synergistic interactions in both combinations, implying that combined treatment of CJY with other modulators may exert synergistic interactions for the drug's penetration into the brain and the treatment of neurological disorders.

In vitro and in vivo study of dolichyl phosphate on the efflux activity of P-glycoprotein at the blood-brain barrier.

It has been commonly recognized that accumulated amyloid-ß (Aß) in the brain plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Since the deficiency of the P-glycoprotein (P-gp) at the blood-brain barrier (BBB) in AD may aggravate Aß deposition and the P-gp reversal agents display lower selectivity of the action, to selectively restore activity of the efflux pump is eagerly required. This study was designed to investigate the influence of dolichyl-phosphate (dolichyl-P) on the P-gp at the BBB. The results revealed that treatment with dolichyl-P increased transendothelial transfer of Rhodamine123 (Rh123) and Aß42 from the apical compartment to the basolateral compartment but reduced that from the basolateral compartment to the apical compartment in the co-culture of rat brain microvessel endothelial cells (rBMECs) and astrocytes, down regulated P-gp expression in rBMECs and significantly elevated content of Rh123 in rat cortex and hippocampus tissues. The present results implied that accumulated dolichyl-P in the brain may exert an important role in the depression of the P-gp at the BBB, which may suggest valuable clues to promote function of the pump at the BBB in AD.

Modulation of P-glycoprotein in rat brain microvessel endothelial cells under oxygen glucose deprivation.

OBJECTIVES: To investigate modulation of P-glycoprotein (P-gp) in rat brain microvessel endothelial cells (rBMECs) under oxygen glucose deprivation (OGD). METHODS: The coculture of rBMECs and astrocytes was established to investigate the time course of P-gp, tumour necrosis factor-α (TNF-α), endothelin-1 (ET-1), nitric oxide synthase (NOS) and protein kinase C (PKC) expression in the rBMECs as well as rhodamine 123 (Rh123) transendothelial transfer under OGD using Western blot and HPLC, respectively. The influence of pharmacological tools including H398, JKC-301, RES-701-1, L-NMMA, BIM and SN50 on the P-gp expression as well as Rh123 transendothelial transfer was evaluated at 3 h time point of OGD. KEY FINDINGS: Elevated P-gp, TNF-α, ET-1, NOS and PKC expression in the rBMECs, as well as increased P-gp efflux activity were observed after 2 h or more time of OGD. Incubation of H398 and other pharmacological tools downregulated P-gp expression and functional activity in the rBMECs at 3 h time point of OGD. CONCLUSIONS: This report suggested that TNF-α, ET-1, NOS and PKC may mediate upregulation of P-gp in the rBMECs under OGD, which may be worthy of being referenced for the investigation of P-gp at the blood-brain barrier in the early period of stroke.

Alteration in P-glycoprotein at the blood-brain barrier in the early period of MCAO in rats.

OBJECTIVES: The aim of this work was to investigate the alteration in P-glycoprotein (P-gp) at the blood-brain barrier (BBB) after middle cerebral artery occlusion (MCAO) in rats. METHODS: Permanent MCAO was verified via 2,3,5-triphenyltetrazolium staining and hematoxylin-eosin staining. The expression of P-gp, matrix metalloproteinase-2 (MMP-2), MMP-9, claudin-5, tumour necrosis factor-α (TNF-α) and nitric oxide synthase (NOS) at the BBB was evaluated using western blot or immunostaining analysis. The content of fluorescein sodium (NaF), rhodamine-123 and nimodipine in ischaemic brain tissues was determined using high-performance liquid chromatography. KEY FINDINGS: Elevated expression of P-gp at the BBB and decreased concentration of P-gp substrates in the ischaemic brain tissues were observed within 4 h after MCAO. However, at 6 h after MCAO, the concentration of P-gp substrates in the ischaemic hemisphere began to rise even though the expression of P-gp was still increased. Moreover, the expression of claudin-5 was decreased; contrarily, the expression of MMP-2, MMP-9, TNF-α as well as NOS gradually increased within 6 h after MCAO. CONCLUSIONS: P-gp plays a crucial role in limiting the entrance of agents into the brain after MCAO and the specific regulation of P-gp expression/activity may provide an important approach for the improvement of pharmacotherapy in ischaemic stroke.

N(1)-(quinolin-2-ylmethyl)butane-1,4-diamine, a polyamine analogue, attenuated injury in in vitro and in vivo models of cerebral ischemia.

It has been widely recognized that glutamate (Glu)-induced cytotoxicity, intracellular calcium overload and excessive free radical production are the key players in the development and progression of ischemic brain injury. Since MK-801, an antagonist of N-methyl-d-aspartate (NMDA) receptor, showed many adverse reactions that hampered its clinical applications, development of safe and effective agent for the treatment of cerebral ischemia is eagerly required. This study was to investigate the effects of N(1)-(quinolin-2-ylmethyl)butane-1,4-diamine (QMA), a polyamine analogue, on the in vitro and in vivo models of cerebral ischemic damage. The results revealed that pretreatment with QMA could attenuate Glu, putrescine (Put) and oxygen-glucose deprivation (OGD)-induced cell death, lipid peroxidation as well as the elevation of reactive oxygen species (ROS) and intracellular [Ca(2+)](i) in pheochromocytoma (PC12) cells and in rat primary cortical neurons. The results also demonstrated that QMA could inhibit NMDA-mediated intracellular [Ca(2+)](i) accumulation in rat primary cortical neurons and reduce brain infarct volume in middle cerebral artery occlusion (MCAO) rats. The present report suggested that polyamines played a crucial role in the pathological processes of cerebral ischemic damage and that QMA or other novel polyamine analogues could be promising therapeutic candidates for stroke by virtue of their anti-hypoxia and antioxidation property.

[Triterpenoids from Inonotus obliquus protect mice against oxidative damage induced by CCl4].

To investigate the effects of lanosterol (1), inotodiol (2) and trametenolic acid (3) from Inonotus obliquus against oxidative damage induced by CCl4 in mice, 1, 2 and 3 (20, 10 and 5 mg x kg(-1)) were respectively administered to mice, once a day for 3 days. Then the mice were induced to oxidative damage by CCl4 on the third day 30 min after the administration. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX) and the content of malondialdehyde (MDA) and reductive glutathione (GSH) in serum and liver homogenate were determined. And the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and interleukin-6 (IL-6) concentration in serum were detected. The results showed that treatment with compound 1, 2 and 3 could significantly increase the activities of SOD, CAT and GSH-PX in serum and liver homogenate. Furthermore, the content of GSH in serum and liver homogenate increased and MDA content decreased markedly. In addition, compound 1, 2 and 3 could significantly inhibit the activities of ALT and AST in serum, and decrease the IL-6 concentration in serum remarkably. So, compound 1, 2 and 3 can protect mice against oxidative stress injury induced by CCl4. Furthermore, compound 1, 2 and 3 can protect cells from damage through inhibition on ALT, AST and the expression of IL-6.

Synthesis, crystal structures, and biological evaluation of Cu(II) and Zn(II) complexes of 2-benzoylpyridine Schiff bases derived from S-methyl- and S-phenyldithiocarbazates.

Two NNS tridentate Schiff base ligands of 2-benzoylpyridine S-methyldithiocarbazate (HL(1)) and 2-benzoylpyridine S-phenyldithiocarbazate (HL(2)) and their transition metal complexes [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1), [Zn(2)(L(1))(2)(ClO(4))(2)] (2), [Zn(L(2))(2)](3) have been prepared and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. In the solid state, each of two Schiff bases remains in its thione tautomeric form with the thione sulfur atom trans to the azomethine nitrogen atom. Under similar prepared conditions, three new complexes showed distinctly different coordination modes depending on their coordinating preferences. Each copper atom in S-bridged dinuclear complex [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1) is surrounded by five donor atoms in a square-pyramidal fashion (4+1). [Zn(2)(L(1))(2)(ClO(4))(2)] (2) is a dimer in which each zinc atom adopts a seven-coordinate distorted pentagonal bipyramidal geometry, while mononuclear [Zn(L(2))(2)] (3) has octahedral coordination geometry. Biological studies, carried out in vitro against selected bacteria, fungi, and K562 leukaemia cell line, respectively, have shown that different substituted groups attached at the dithiocarbazate moieties and metals showed distinctive differences in the biological property. Zinc(II) complexes 2 and 3 could distinguish K562 leukaemia cell line from normal hepatocyte QSG7701 cell line. Effect of the title compounds on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity in K562 leukaemia cell line are also studied. The title compounds may exert their cytotoxicity activity via induced loss of MMP.

Synthesis, crystal structures, and biological evaluation of manganese(II) and nickel(II) complexes of 4-cyclohexyl-1-(1-(pyrazin-2-yl)ethylidene)thiosemicarbazide.

4-Cyclohexyl-1-(1-(pyrazin-2-yl)ethylidene)thiosemicarbazide (HL) and its transition metal complexes formulated as [Mn(L)(2)] (1) and [Ni(L)(2)] (2) have been prepared in 55-75% yield and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. Biological activities of the synthesized compounds have been evaluated against selected Gram positive bacteria Bacillus subtilis, Gram negative bacteria Pseudomonas aeruginosa and the K562 leukemia cell line, respectively. The cytotoxicity data suggest that these compounds may be endowed with important biological properties, especially the nickel complex 2 with MIC = 31.2 µg/mL and IC(50) = 0.53 µM, respectively. Effect of the free ligand and its two complexes on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity as well as their effect on cell apoptosis in K562 leukemia cell line was also studied. The tested compounds may exert their cytotoxicity activity via induced loss of MMP.

Interaction of CJZ3, a lomerizine derivative, with ATPase activity of human P-glycoprotein in doxorubicin-resistant human myelogenous leukemia (K562/DOX) cells.

P-Glycoprotein, a 170-180 kDa membrane glycoprotein that mediates multidrug resistance, hydrolyses ATP to efflux a broad spectrum of hydrophobic agents. To observe the interaction of a P-gp reversal agent with P-gp ATPase activity should provide further insights into the mechanisms of P-gp modulator. In this study, we analysed the effect of CJZ3, a lomerizine derivative, on the adenosine triphosphatase (ATPase) activity of human P-glycoprotein. The results showed that the basal P-gp ATPase activity was increased by CJZ3 with half-maximal activity concentration (Km) of 6.8 +/- 1.5 microM, CJZ3 may interact with P-gp with a higher affinity and exhibit a more potent effect than verapamil (Ver). Kinetic analysis indicated a noncompetitive inhibition of Ver-stimulated P-gp ATPase activity and a competitive inhibition of CJX2-stimulated P-gp ATPase activity by CJZ3, moreover, the effect of CsA on CJZ3-stimulated and Ver-stimulated P-gp ATPase activity showed a non-competitive and a competitive inhibition respectively. CJZ3 and CJX2 can bind P-gp either on overlapping sites or distinct but interacting sites, while CJZ3 and Ver as well as CsA can bind P-gp on separated sites in K562/DOX cells.

Mn(II), Co(II) and Zn(II) complexes with heterocyclic substituted thiosemicarbazones: synthesis, characterization, X-ray crystal structures and antitumor comparison.

Transition metal complexes Mn(L(1))(2) (1), Mn(L(2))(2) (2), Co(L(3))(2)Cl 4H(2)O (3), Zn(L(3))(2) DMF (4), Co(HL(4))(2)(ClO(4))(2) 3H(2)O (5) and Zn(L(5))(2) DMF (6) where HL(1)=2-acetylpyridine thiosemicarbazone, HL(2)=2-acetylpyridine N(4)-methylthiosemicarbazone, HL(3)=2-benzoylpyridine thiosemicarbazone, HL(4)=2-benzoylpyridine N(4)-methylthiosemicarbazone and HL(5)=2-benzoylpyridine N(4)-phenylthiosemicarbazone, have been synthesized. The complexes 1, 2, 5 and 6 were characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction studies. Preliminary in vitro screening indicated that all the tested compounds showed significant antitumor activity against K562 leucocythemia cancer cell line.

The protective effect of trihexyphenidyl on the beta-amyloid peptide (25-35)-induced cytotoxicity in PC12 cells.

In the development and progression of Alzheimer's disease (AD), ß-amyloid peptide (Aß) that induced cytotoxicity containing apoptosis and excess production of reactive oxygen species (ROS) is considered as a causal role. The aim of present study is to investigate the protective effect of Trihexyphenidyl (THY) on Aß(25-35)-induced cytotoxicity in cultured rat pheochromocytoma (PC12) cells. In this report, the cell survival was measured by MTT assay, the enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), the contents of lipid peroxidation products malondialdehyde (MDA) and ROS in the cells were determined. Acridine orange (AO) was used to observe the morphological characteristic of apoptotic cells. Mitochondrial membrane potential in PC12 cells were monitored by fluorospectrophotometer combining with Rh123. As a cell permeable fluorescent probe, Fura-2/AM was employed to detect intracellular [Ca(2+)]. The results showed that after incubation with Aß(25-35) (10 µM) for 24 h, there were decreased changes in cell viability, SOD, and GSH-PX activity as well as mitochondrial membrane potential, in contrast, the levels of [Ca(2+)](i), ROS, and MDA were increased, THY significantly attenuated all the changes induced by Aß(25-35), indicating that THY exhibited protective effect against Aß(25-35)-induced cytotoxicity, which may represent the cellular mechanisms of the action.

CJX1, an amlodipine derivative, interacts with ATPase of human P-glycoprotein.

Our aim has been to elucidate the possible mechanism of CJX1, an amlodipine derivative, in the modulation of P-gp function by determining its effect on P-gp ATPase activity. Basal P-gp ATPase activity was increased by CJX1 with half-maximal activity concentration (Km) of 8.6+/-1.4 microM. Kinetic analysis indicated a non-competitive inhibition of Verapamil (Ver)-stimulated P-gp ATPase activity by CJX1 and competitive inhibition of CJX1-stimulated P-gp ATPase activity by tetrandrine (Tet). The effect of CsA on CJX1-stimulated and Ver-stimulated P-gp ATPase activity was non-competitive and competitive inhibition, respectively. These findings implying that CJX1 and Tet can bind P-gp either on overlapping sites or distinct but interacting sites, while CJX1 and Ver as well as CsA can bind P-gp on separated sites in K562/DOX cells. Furthermore, the combined effect of CJX1 and Ver has been evaluated isobolographically in numerous fixed-ratio combinations of 1:1, 1:2, 1:4, 1:8, 1:10 in K562/DOX cells. The results show that mixtures of both drugs at these fixed-ratios exerted synergistic interactions, indicating that when the two reverses that bind P-gp on separated sites are combined, each can contribute to the overall interaction with P-gp, leading to the greater effect than that by either agent alone.

Cytotoxicity and structure-activity relationships of four alpha-N-heterocyclic thiosemicarbazone derivatives crystal structure of 2-acetylpyrazine thiosemicarbazone.

A series of thiosemicarbazone ligands, HL(1) (2-acetylpyrazine thiosemicarbazone), HL(2) (2-acetylpyrazine N(4)-methylthiosemicarbazone), HL(3) (2-benzoylpyridine thiosemicarbazone) and HL(4) (2-benzoylpyridine N(4)-methylthiosemicarbazone), have been synthesized. The crystal structure of HL(1) has been determined by single-crystal X-ray diffraction. Hydrogen bonds link the different components to stabilize the crystal structure. The antitumor activity of the four ligands were tested against K562 leucocythemia and BEL7402 liver cancer cell lines. All the thiosemicarbazones showed significant antitumor activity. Different substituents on the ligands show different levels of antitumor activity. By comparison with the other thiosemicarbazone species studied, HL(4) with substitution at N(4) position in thiosemicarbazone along with 2-benzoylpyridine is the most active thiosemicarbazone ligand with IC(50)=0.002microm in the K562 leucocythemia cell line and 0.138microm in the BEL7402 liver cancer cell line, respectively.

HL-37, a novel anthracene derivative, induces Ca(2+)-mediated apoptosis in human breast cancer cells.

HL-37, a novel anthracene derivative, exhibited potent anticancer activity in many kinds of cancer cells. However, the exact mechanism and signaling pathway involved in HL-37-induced apoptosis have not been fully elucidated. Therefore, we explored the mechanisms of HL-37-mediated apoptosis in MCF-7 and MDA-MB-435 human breast cancer cells. When MCF-7 cells or MDA-MB-435 cells were co-incubated with HL-37, the percentage of apoptotic cell and S phase of cell cycle was markedly increased. In addition, a rise in intracellular calcium levels, ROS production, phosphorylation of JNK and activation of calpain were found in both MCF-7 cells and MDA-MB-435 cells after exposure to HL-37. With the HL-37-mediated reduction of mitochondrial membrane potential, cytochrome c was released from mitochondria to cytosol. Moreover, HL-37 strongly induced cleavage of caspase-4, caspase-9, as well as caspase-3 in MDA-MB-435 cells, whereas, activation of caspase-4, caspase-9 and caspase-7 but not caspase-3 was detected in MCF-7 cells. These results suggested that HL-37 induced MDA-MB-435 and MCF-7 cells apoptosis via oxidative stress and Ca(2+)/calpain/caspase-4 pathway.

In vitro and in vivo study of CJY, an isoflavone, on p-glycoprotein function in rats.

The p-glycoprotein is a transmembrane efflux transporter found on the luminal side of the capillary endothelial cells that comprise the blood-brain barrier. This study examined the effect of CJY, an isoflavone, on the levels of a p-glycoprotein substrate, rhodamine123 (Rh123), in rat brain microvessel endothelial cells (RBMEC) and in rat brain homogenate using fluorescence spectrophotometer and high performance liquid chromatography, respectively. In the in vitro study, incubation of RBMEC cells with CJY caused a marked increase in uptake and a notable decrease in efflux of Rh123. The inhibitory effect of the agent on P-gp function was reversible and remained even after the 2.5microM agent was removed from the medium for 120 min. In the in vivo study, CJY also elevated the Rh123 levels in rat brain homogenate after the rats received a 0.45 mg/kg dose of the CJY by slow intravenous injection, indicating that CJY may be a candidate as a p-glycoprotein inhibitor.

Protective effect of trihexyphenidyl on hydrogen peroxide-induced oxidative damage in PC12 cells.

The protective effect of trihexyphenidyl (THY) on hydrogen peroxide-induced oxidative damage was investigated in the rat pheochromocytoma line PC12 cells. Following the exposure of PC12 cells to H(2)O(2), there was a reduction in cell survival, activities of superoxide dismutase (SOD) and mitochondria membrane potential (MMP), in contrast, the increased levels in Lactate dehydrogenase (LDH) release, malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS), as well as intracellular [Ca(2+)]i level were observed. However, preincubation of cells with THY prior to H(2)O(2) exposure attenuated all the changes mentioned above, THY exhibited protective effect against H(2)O(2)-induced toxicity in PC12 cells, indicating that the compound may be a potential therapeutic agent for the diseases influenced by oxidative damage.