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Antiepileptic drug therapy in individuals with epilepsy can induce free radical generation and profound lipid peroxidation. Some Chinese herbs with antiepileptic potential show antioxidant effects. We performed an open add-on study of TW970, a modified formula of the Chinese medicine "Chaihu-Longu-Muli-Tang", on 20 patients with refractory epilepsy and a seizure frequency of at least four fits per month, and another 20 patients with benign epilepsy and a seizure frequency of less than four fits per month. The control group consisted of 20 age-matched healthy adults. Seizure frequency, serum malondialdehyde (MDA), glutathione (GSH) and copper-zinc superoxide dismutase (Cu,Zn-SOD) were investigated in patients with refractory and benign epilepsy before and after four months add-on treatment of TW970. There was a decrease in seizure frequency in refractory epileptics from 13.4 ± 3.4 to 10.7 ± 2.5/per month, although the p value was 0.084. Before TW970 add-on treatment, a significant enhancement of lipid peroxidation with increased MDA and Cu,Zn-SOD activities together with decreased GSH were seen in refractory epileptics compared with normal controls. After TW970 add-on treatment of refractory epileptics for four months, normalization of MDA and Cu,Zn-SOD levels was achieved. Before and after TW970 add-on treatment, there were no statistically significant changes of the above-mentioned parameters in the patients with benign epilepsy. These results suggest that TW970 can reduce the seizure frequency in patients with refractory epilepsy and this may be due to the antioxidant effects of the modified formula of Chaihu-Longu-Muli-Tang.

The water extracts of Cornus officinalis Sieb. et Zuce against hepatocellular carcinoma (HCC) was studied for its chemopreventive potential. Three HCC cell lines (HepG2, SK-Hep1 and PLC/PRF/5) and three leukemic cell lines (U937, K562 and Raji) were tested with XTT assay. Extracts of C. officinalis inhibited all these HCC cells and leukemic cells at a concentration of 100 μg/ml (P<0.05) and was dose-dependent (P<0.0001). P53 (P<0.0001) and Ras (P=0.001) significantly affected its activity against HCC. Extracts of C. officinalis also possessed the anti-oxidant activity through free radicals scavenging activity at a concentration of 50 μg/ml (P<0.05). In summary, our experiment implied that C. officinalis might be a candidate for chemopreventive agent against HCC through the antioxidant and anti-neoplastic effects.

The stem and root of Porcelainberry (Ampelopsis brevipedunculata (Maxim.) Trautv.) (AB) was traditionally used as an anti-inflammatory, diuretic and anti-hepatotoxic agent in folk medicine. In this study, cell-free and cell culture systems were employed to investigate the antioxidant activity of the methanol extract of AB (MEAB). The cell-free system showed that the MEAB exhibited dose-dependent antioxidant activities against linoleic acid peroxidation and plasmid DNA oxidation. We also demonstrated that the MEAB possessed strong reducing power and scavenging effects of hydroxyl radicals and DPPH free radicals.

The harmful effects of reactive oxygen metabolites on HepG2 cells and the possible antioxidant effects of the MEAB were also investigated. Pretreatment or cotreatment of HepG2 cells with the MEAB could significantly protect cells from H₂O₂-induced oxidative stress. This implies that the antioxidant effects in cell culture may result from the direct interaction between the MEAB and exogenous oxidant sources, as these occur in cell free systems, as well as from the induction of cellular stress gene expression. The antioxidant activity of the MEAB may partially explain its anti-inflammatory and anti-hepatotoxic effects.

Nausea and vomiting are significant adverse effects of chemotherapeutic agents like cisplatin, and cause significant patient morbidity. Cisplatin treatment results in oxidant gut injury, which is postulated to be the primary cause of nausea and vomiting. We evaluated the effects of two antioxidant herbs, Scutellaria baicalensis and American ginseng berry, on cisplatin-induced nausea and vomiting using a rat model. Rats react to emetic or nausea-producing stimuli, such as cisplatin, with altered feeding habits, manifested by increased kaolin consumption (pica). We measured pica in rats to quantify cisplatin-induced nausea. We observed that pretreatment of rats with S. baicalensis or ginseng berry extracts resulted in a significant reduction in cisplatin-induced pica. The in vitro free radical scavenging ability of the herbal extract observed in the study, further confirmed the antioxidant action of the herb. We conclude that herbal antioxidants may have a role in attenuating cisplatin-induced nausea and vomiting.

Hawthorn (Crataegus) may play a role in the prevention and treatment of cardiovascular diseases such as hypertension, hyperlipidemia, and in particular, congestive heart failure. Evidence is accumulating that hawthorn may induce anti-ischemia/reperfusion-injury, anti-arrhythmic, hypolipidemic and hypotensive effects. These beneficial effects may in part be due to the presence of antioxidant flavonoid components. While a number of studies have been performed to evaluate the clinical efficacy of hawthorn, an international, multi-center, prospective clinical study including a large number of New York Heart Association (NYHA) class II/III heart failure patients is ongoing to test hawthorn's long-term therapeutic effects. Further clinical trials as well as pharmacokinetic and mechanistic studies are needed to explore and confirm its effectiveness, safety and pharmacological mechanism.

This study evaluated the antioxidant and antiproliferative activities of the crude extract and fractions of Desmodium triflorum (L.) DC. The total phenolic content, 1,1-diphenyl-2- picrylhydrazyl hydrate (DPPH) free radical scavenging activity, trolox equivalent antioxidant capacity (TEAC), reducing power, total flavonoid content of D. triflorum were evaluated for the exploration of its antioxidant activities. Furthermore, its antiproliferative activities were investigated through the MTT method. It was compared with the antioxidant capacities of known antioxidants, including catechin, α-tocopherol, trolox and ascorbic acid. Among all fractions, ethyl acetate fraction was the most active in scavenging DPPH and TEAC radicals, of which 0.4 mg was equivalent to 186.6 ± 2.5 μg and 82.5 ± 2.1 μg of α-tocopherol and trolox respectively. The total phenolic and flavonoid contents of the crude extract were equivalent to 36.60 ± 0.1 mg catechin and 45.6 ± 0.6 mg rutin per gram respectively. In the reducing power assay, 1.25 mg of crude extract was similar to 61.2 ± 0.3 μg of ascorbic acid. For the assessment of the safety and toxicity of D. triflorum, LD₅₀ of the crude extract was greater than 10 g/kg when administered to mice through gastric intubation. The above experimental data indicated that D. triflorum was a potent antioxidant medicinal plant, and such efficacy may be mainly attributed to its polyphenolic compounds.

Exploration and characterization of grafting productions by experimental methods are often cumbersome or sometimes impossible. Therefore, quantum chemistry calculations were performed to characterize the graft sites of epoxy resin. According to the Gibbs free energy criterion of the second law of thermodynamic, the reported graft sites were confirmed, and more important, some unreported graft sites were found. In addition, method of increasing the number of graft sites was studied in this article.

More than 90 individual mutations in copper-zinc superoxide dismutase are associated with familial cases of amyotrophic lateral sclerosis and they are mostly fatal within one to five years of the onset of the disease. Results obtained from studies with transgenic mice, transfected cells, and patients suggest that familial amyotrophic lateral sclerosis copper-zinc superoxide dismutase mutants have gains or enhancements in one or more cytotoxic properties, which are not related to the superoxide dismutation activity. The proposed nature of the cytotoxic gain-of-function of the familial amyotrophic lateral sclerosis copperzinc superoxide dismutase mutants under debate includes enhanced free radical-generating (peroxidative) activity, enhanced activity of peroxynitrite-mediated tyrosine nitration, and familial amyotrophic lateral sclerosis mutant-associated aggregate formation due to failure of protein folding. We review these proposals and summarize our findings from the studies with purified familial amyotrophic lateral sclerosis copper-zinc superoxide dismutase mutants.

One fundamental mechanism widely described for nanotoxicity involves oxidative damage due to generation of free radicals and other reactive oxygen species. Indeed, the ability of nanoscale materials to facilitate the transfer of electrons, and thereby promote oxidative damage or in some instances provide antioxidant protection, may be a fundamental property of these materials. Any assessment of a nanoscale material’s safety must therefore consider the potential for toxicity arising from oxidative damage. Therefore, rapid and predictive methods are needed to assess oxidative damage elicited by nanoscale materials. The use of electron spin resonance (ESR) to study free radical related bioactivity of nanomaterials has several advantages for free radical determination and identification. Specifically it can directly assess antioxidant quenching or prooxidant generation of relevant free radicals and reactive oxygen species. In this chapter, we have reported some nonclassical behaviors of the electron spin relaxation properties of unpaired electrons in different fullerenes and the investigation of anti/prooxidant activity by various types of nanomaterials using ESR. In addition, we have reviewed the mechanisms of free radical formation photosensitized by different nanomaterials. This chapter also included the use of spin labels, spin traps and ESR oximetry to systematically examine the enzymatic mimetic activities of nanomaterials.