Adolescent ; Adult ; Altitude ; Exercise ; Free Radicals ; metabolism ; Humans ; Male ; Placebos ; Tyrosine ; pharmacology ; Young Adult

Animals ; Brain ; drug effects ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Free Radicals ; metabolism ; Rats ; Rats, Wistar ; Sports

OBJECTIVEIn order to explore the pathway of dealkylation of pesticides other than cytochrome P450 monocoxygenases, lipoxygenase (LOX)-mediated demethylation of aminocarb and some other pesticides were measured.

METHODFormaldehyde generated in the reaction was estimated by Nash reaction to express the rate of demethylation of pesticides mediated by soy lipoxygenase (SLO).

RESULTSN-demethylation of aminocarb mediated by SLO was found to depend on the incubation time, concentration of the enzyme, concentration of aminocarb and hydrogen peroxide. Under optimal conditions, Vmax value of 18 nmol of formaldehyde.min-1.nmol-1 of lipoxygenase was observed. The reaction exhibited Km values of 3.4 mmol/L for aminocarb and 235 mumol/L for hydrogen peroxide. A strong inhibition of the reaction by nordihydroguaiaretic acid, gossypol, and phenidone clearly implicated the lipoxygenase involvement as the protein catalyst. A significant decline in the formaldehyde accumulation in the presence of either reduced glutathione or dithiothreitol suggested generation of a free radical species as an initial oxidation intermediate during the demethylation of aminocarb by SLO. The inhibition of formaldehyde generation by butylated hydroxyanisole(BHT) and butylated hydroxy toluene(BHA) further supported this contention. In addition to aminocarb, seven other pesticides were also found to undergo N-demethylation, albeit at relatively low rates.

CONCLUSIONCertain pesticides may oxidatively undergo dealkylation via the lipoxygenase pathway in animals and plants.

Butylated Hydroxyanisole ; pharmacology ; Butylated Hydroxytoluene ; pharmacology ; Dealkylation ; Free Radicals ; Lipoxygenase ; physiology ; Pesticides ; metabolism ; Phenylcarbamates ; metabolism ; Soybeans ; enzymology

OBJECTIVETo investigate the effect of the "compound extract of Chinese medicine" on free radical metabolism and antioxidant enzyme systems of the rat brain.

METHODS70 Wistar mice were randomly divided into two groups (n = 35): normal control group (N), taking medicine group (M). After a week of feeding, M group was taking medicine for 8 weeks. After 9 weeks, killed the two groups when they were at the rest state, the immediate ends of the fixed load, the immediate ends of exhaustive exercise and 12, 24 hour ends of exhaustive exercise, respectively. And the activity of malonaldehyde (MDA), glutathione peroxidase (GSH-PX), glutathione (GSH), superoxide dismutase (SOD), total anti oxidation capacity (T-AOC) of the rat brain were measured.

RESULTSAt the five states, the content of MDA in M group was lower than that in N group in different degree, the activity of GSH-PX, GSH, SOD, T-AOC in M group were higher than those in N group in different degree.

CONCLUSIONThe "Compound extract of Chinese medicine" can reduce the MDA level of the rat brain and improve the enzyme activity of GSH-PX, GSH, SOD, T-AOC.

Animals ; Antioxidants ; pharmacology ; Brain ; drug effects ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Free Radicals ; metabolism ; Rats ; Rats, Wistar

To investigate the effects of the free radical, 1,1-Diphenyl-2-picylhydrazyl, on cochlear blood flow, 20 guinea pigs were divided into 3 groups at random, 6 for control group, 6 for 1 mmol/L group and 8 for 0.1 mmol/L group. 2 microliters vehicle or drugs were dropped into round window membrane (RWM). Cochlear microcirculation was monitored by laser Doppler flowmeter (LDF), and mean arterial blood flow (MABP), which was transferred by pressure conductor sensor and preamplifier, was simultaneously recorded on the computer. Our results showed that MABP was stable throughout the experiment. Cochlear blood flow (CBF) increased by 10.32% (P < 0.05) in 1 mmol/L group, and decreased by 4.89% in 0.1 mmol/L group (P < 0.05). In control group cochlear microcirculation showed no significant changes. It is concluded that DPPH exerted effects on cochlear microcirculation.
Blood Flow Velocity ; Cochlea/*blood supply ; Free Radicals/pharmacology ; Laser-Doppler Flowmetry ; Microcirculation/drug effects ; Picrates/*pharmacology ; Random Allocation

OBJECTIVETo evaluate the antioxidant activities of different chemical constituents from Astragalus mongholicus Bunge and their protection against xanthine (XA)/xanthine oxidase (XO)-induced toxicity in PC12 cells.

METHODSThe compounds of Astragalus mongholicus Bunge were isolated by chromatography and the structures were elucidated on the basis of spectral data interpretation. Their antioxidant activities were detected by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities in a cell-free system. Meanwhile, the effects against XA/XO-induced toxicity were assessed using MTT assay in PC12 cells.

RESULTSTen principal constituents were isolated and identified as formononetin (I), ononin (II), calycosin (III), calycosin-7-O-beta-D-glucoside (IV), 9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (V), adenosine (VI), pinitol (VII), daucosterol (VIII), beta-sitoster (IX) and saccharose (X) from Astragalus mongholicus Bunge. The compounds I, III, and IV scavenged DPPH free radicals in vitro. Formononetin and calycosin were found to inhibit XA/XO-induced cell injury significantly, with an estimated EC50 of 50 ng/mL.

CONCLUSIONCompound II, VI, and VII are first reported in this plant. Calycosin exhibits the most potent antioxidant activity both in the cell-free system and in the cell system.

Animals ; Astragalus Plant ; chemistry ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Free Radical Scavengers ; chemistry ; pharmacology ; Free Radicals ; metabolism ; Isoflavones ; chemistry ; pharmacology ; PC12 Cells ; Rats ; Xanthine ; toxicity ; Xanthine Oxidase ; toxicity

OBJECTIVETo develop a simple, reliable approach for evaluating the quality of Huangqin (Scutellaria baicalensis).

METHODTo determine the DPPH free radical scavenging activity and assay of four bioactive components: baicalin, baicalein, wogonin and wogonin-7-O-glucuronide by HPLC.

RESULTThe correlative relationship between DPPH free radical scavenging activity and baicalin content was obtained.

CONCLUSIONBioassay of DPPH free radical scavenging activity could be used as one of the methods for quality evaluation of Chinese drug Huangqin.

Biphenyl Compounds ; Flavanones ; Flavonoids ; chemistry ; isolation & purification ; pharmacology ; Free Radical Scavengers ; pharmacology ; Free Radicals ; Molecular Structure ; Picrates ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry ; Quality Control ; Scutellaria baicalensis ; chemistry

Animals ; Drugs, Chinese Herbal ; pharmacology ; Free Radicals ; metabolism ; Male ; Myocardium ; metabolism ; Physical Conditioning, Animal ; Rats ; Rats, Wistar

BACKGROUND: Cytosolic Ca2+ overload and oxygen derived free radicals may contribute to stunned myocardium. The pnt study was aimed to investigate the effects of nicardipine and sodium nitroprusside (SNP) on the functional recovery of postischemic reperfused myocardium. METHODS: Fifty-seven halothane-anesthetized dogs were subjected to 15 minutes of 1eft anterior descending coronary artery (LAD) occlusion and 3 hours of reperfusion. They were randomly assigned to receive either intracoronary nicardipine (n=11) or SNP (n=10) alone or both (nicardipine plus SNP, n=10). Eleven dogs that received saline i.c. served as the controL Regional myocardial contractility was evaluated by systolic shortening (%SS), the preload recruitable stroke work slope (Mw), and intramyocardial pressure (IMPs). Diastolic function was assessed by time constant of myocardial relaxation (IMP-tau) and postsystolic shortening (%PSS), LAD blood flow was measured by a Doppler flowmeter as well. RESULTS: LAD occlusion produced a significant reduction in systolic as well as diasto1ic functions to similar degrees in all groups. However, %SS was significantly higher in the nicardipine, SNP and nicardipine-SNP groups (67%, 56%, and 68% of baseline values, respectively) than in the controls (20%) at 3 hours of reperfusion. Furthermore, Mw recovered to the baseline with the onset of reperfusian in the three experimental groups. IMP-tau was restored to the baseline during early nperfusion in the SNP-treated groups but was significantly prolonged in the control and nicardipine poups throughout the seperfusion. LAD blood flow during reperfusion was higher in the SNP-treated groups in comparison to the control group. CONCLUSIONS: Treatment with either nicardipine or SNP enhances the recovery of mgional contractile function in the canine model of myocardial stunning. SNP not nicardipine is also beneficial in attenuation of early diastolic dysfunction. Nicardipine combined with SNP improved systolic as well as early diastolic functions more significantly when compared to either nicardipine or SNP alane.
Animals ; Coronary Vessels ; Cytosol ; Dogs* ; Flowmeters ; Free Radicals ; Heart ; Myocardial Stunning* ; Myocardium ; Nicardipine* ; Nitroprusside* ; Oxygen ; Pharmacology ; Relaxation ; Reperfusion ; Sodium* ; Stroke

OBJECTIVETo observe the effects of Huanglian Jiedu Decoction (HLJDT) on the metabolism of free radicals, the morphology and histopathology of hippocampal CA1 neurons in PS1/APP double transgenic mice of Alzheimer's disease (AD), and to study its possible mechanisms, thus providing experimental evidence for treating AD by HLJDT.

METHODSThe APP/PS1 double transgenic mouse model was used. Mice were randomly divided into five groups, i. e., the model control group, the positive control group (Aricept), high-, middle-, and low-dose HLJDT group (at the daily dose of 865 mg*kg(-1), 433 mg*kg(-1), and 216 mg*kg(-1), respectively). Corresponding medication was daily given by gastrogavage. Seven months later superoxide dismutase (SOD) and malondialdehyde (MDA) were detected at the ten-month old mice, thus observing the effects on the morphology of CA1 hippocampal neurons and the senile plaques (SP).

RESULTSHLJDT and Aricept could obviously increase the SOD contents and lower the MDA contents (P<0.05), attenuate the destroy of neurocytes and the formation of SP, effectively hinder the degeneration of hippocampal neurons. Better results were obtained in the middle-dose HLJDT group than in the positive control group (P<0.05).

CONCLUSIONThe mechanism of HLJDT in treating AD might be possibly correlated with improving anti-oxygenation, protecting hippocampal neurocytes, and reducing the formation of SP.

Alzheimer Disease ; metabolism ; pathology ; Animals ; Drugs, Chinese Herbal ; pharmacology ; Free Radicals ; metabolism ; Hippocampus ; drug effects ; pathology ; Male ; Mice ; Mice, Transgenic