Cis-1,2-dihydroxycyclohexa-3,5-diene (DHCD) can be used as a valuable chiral intermediates for applications in pharmaceuticals, aerospace, electrical and fine chemical industries. By on-line detection of toluene dioxygenase (TDO) activity in whole recombinant Escherichia coli JM109 (pKST11) cells that harbored TDO gene under a tac promoter, effects of IPTG and various benzene addition strategies on bioransformation of benzene to DHCD were investigated. When IPTG was used at the beginning of fermentation, the growth of cells was inhibited and TDO activity only maintained for 4 hours while same experiments with addition of IPTG at 6h or 8h generated TDO activity for 18 hours. Suitable induction time for IPTG was in the cell logarithmic growth phase and 0.5 mmol/L IPTG was sufficient for inducing maximum TDO activities. Benzene strongly inhibited the activity of TDO which catalyses the conversion of benzene to DHCD. It was found that both cell growth and TDO activity was remarkably inhibited by feeding of benzene vapor, only 7.5 g/L DHCD was obtained. While the benzene inhibition effect was ameliorated by two-liquid phase culture fermentation in which liquid paraffin was used as second phase in the broth. Using different initial ratios of paraffin to benzene in fed-batch culture, DHCD contents were increased to 22.6 g/L, which was 3-fold more compared with that in benzene vapor culture. A further improvement of DHCD production was achieved when the mixture of liquid paraffin and benzene was added continuously by peristaltic pump, the DHCD contents were increased to a final concentration of 36.8 g/L. It was proven that the key to improving DHCD production by recombinants is to prolong TDO activity in cells, which can be achieved by using suitable addition benzene strategies.
Benzene ; metabolism ; Cyclohexanols ; metabolism ; Escherichia coli ; genetics ; metabolism ; Fermentation ; physiology ; Oxygenases ; genetics ; metabolism

BACKGROUNDRecent studies have indicated that chronic stress may give rise to brain damage, which is related to the genesis of depression. The purpose of this study is to investigate the effects of extract of Ginkgo biloba (EGb) and venlafaxine on depression.

METHODSRats were treated with chronic and comprehensive stress to create a depression model. Immunohistochemistry was used to detect the expression of brain-derived neurotrophic factor (BDNF) in the hippocampal CA3 neurons of rats treated with different drugs. Behavioral changes of these rats were also examined.

RESULTSThe expression of BDNF in the hippocampal CA3 neurons of the depression model decreased with a reduction in exploring behavior and a significant increase in fecal production. The expression of neuron nitric-oxide synthase (nNOS) protein also increased in the rats compared to normal controls. The rats treated with EGb and venlafaxine showed an increase in expression of BDNF and exploring behavior compared to untreated rats, but a decrease in nNOS and fecal production.

CONCLUSIONSRats sustain damage to the brain after being subjected to chronic and comprehensive stress. Our research has indicated that combined EGb with venlafaxine enhances the protection of neurons and decreases damage to the brain, while relieving the side effects of synthetic antidepressants.

Animals ; Antidepressive Agents, Second-Generation ; administration & dosage ; Brain Injuries ; complications ; metabolism ; Brain-Derived Neurotrophic Factor ; biosynthesis ; Cyclohexanols ; administration & dosage ; Depression ; drug therapy ; etiology ; Drugs, Chinese Herbal ; administration & dosage ; Ginkgo biloba ; chemistry ; Hippocampus ; metabolism ; Male ; Phytotherapy ; Rats ; Rats, Wistar ; Venlafaxine Hydrochloride

Using site-directed mutagenesis technique, I have replaced serine 285 and serine 292 with the alanine, and assessed the binding of agonist and signaling such as the inhibition of adenylyl cyclase activity.I have found that serine 292 has an important role in the signal transduction of cannabinoid agonists, HU-210 and CP55940, but not in that of aminoalkylindoles derivatives WIN55,212-2. All mutants express well in protein level determined by western blot using monoclonal antibody HA 11 as compared with the wild type receptor.Interestingly, binding affinity of S285A and S292A mutants with classical cannabinoid agonist HU-243 was somewhat decreased. In signaling assay, the inhibition of adenylyl cyclase by HU-210, CP55940 and WIN55, 212-2 is the same order in both wild type receptor and S285A mutant receptor. However, S292A have been shown that the inhibition curves of adenylyl cyclase activity moved to the right by HU-210 and CP55940, but those of adenylyl cyclase activity did not by aminoalkylindole WIN55,212-2, which is indicating that this residue is closely related to the binding site with HU-210 and CP55940. In addition, serine 292 might take more important role in CB2 receptor and G-protein signaling than serine 285.
Adenylate Cyclase/*metabolism ; Animals ; Binding, Competitive ; Blotting, Western ; COS Cells ; Cannabinoids/metabolism ; Cercopithecus aethiops ; Cyclohexanols/metabolism ; Excitatory Amino Acid Antagonists/metabolism ; Mutagenesis, Site-Directed ; Protein Conformation ; Protein Structure, Tertiary ; Receptors, Cannabinoid ; Receptors, Drug/genetics/metabolism/*physiology ; Serine/metabolism/*physiology ; Signal Transduction/physiology ; Tetrahydrocannabinol/*analogs&derivatives/metabolism ; Transfection

OBJECTIVETo evaluate the effect of venlafaxine on the cognitive impairment of learning and memory in rats with post-stroke depression (PSD) and to investigate its relationship with the expression of brain-derived neurotrophic factor (BDNF) in hippocampus.

METHODSFifty male adult SD rats were randomly divided into control group, model group and three treatment groups (5,10, 20 mg*kg(-1) venlafaxine) with ten in each group. After the procedure of selective cerebral right middle artery embolism, a paradigm of continuous 3-week chronic unpredictable mild stress (CUMS) was used to induce PSD. Along with the course of CUMS the peritoneal injection at different dose levels of venlafaxine were performed once a day in PSD rats in a fixed time interval. Morris water maze test was applied to assess the spatial learning and memory function and immunohistochemical staining was used to detect the change of BDNF expression.

RESULTSThe learning function decreased significantly in PSD rats compared with the control (P<0.05), as well as in spatial exploring time (14.2 s ± 4.8 s Compared with 45.9 s ± 4.5 s) and frequency of spanning platform (1.3 ± 0.3 Compared with 8.3 ± 1.1). Moreover,very fewer BDNF positive cells were found in CA3 area of hippocampus in model group in comparison with the control group (9.8 ± 3.2 Compared with 18.5 ± 4.7). After different dosage of venlafaxine treatment, the BDNF expression and cognition increased markedly.

CONCLUSIONVenlafaxine can improve PSD-induced learning and memory dysfunction, possibly through the enhancement of the BDNF level in the CA3 area of hippocampus.

Animals ; Brain-Derived Neurotrophic Factor ; metabolism ; Cyclohexanols ; administration & dosage ; therapeutic use ; Depression ; drug therapy ; etiology ; metabolism ; Disease Models, Animal ; Hippocampus ; drug effects ; metabolism ; Male ; Maze Learning ; drug effects ; Memory ; drug effects ; Memory Disorders ; drug therapy ; etiology ; Rats ; Rats, Sprague-Dawley ; Stroke ; complications ; metabolism ; Venlafaxine Hydrochloride

This study is to evaluate the anti-diabetic effects of the alpha-glucosidase inhibitor valibose in a streptozotocin (STZ)-induced type 1 diabetes rat model. Diabetes was induced by a single dose of STZ (58 mg x kg(-1), ip) in SD rats, rats with elevated fasting blood glucose levels (250-450 mg x dL(-1)) were selected and divided into five groups (n = 10 in each). Another ten normal SD rats were chosen as normal group. Valibose mixed with the high sucrose diets (0.4, 1.0 and 2.5 mg 100 g(-1) diets) or acarbose (30 mg x 100 g(-1) diets) was administrated in the diabetic rats for about 5 weeks. In all groups, fasting and postprandial plasma glucose, plasma lipids, glycosylated serum protein, N-acetyl-beta-D-glucosaminidase (NAG), creatinine (Cre), blood urea nitrogen (BUN) and urine sugar levels were determined during the treatment. At the end of the experiment, the morphological alterations in kidney were evaluated by hematoxylin-eosin (HE) staining. After 3-weeks administration, valibose significantly decreased postprandial and fasting blood glucose, urine glucose, and reduced the levels of serum fructosamine. Valibose also decreased plasma triglyceride and cholesterol levels after 4 weeks treatment. These results indicated that valibose ameliorated metabolic disturbance of glucose and lipids in STZ-induced diabetic rats. In addition, valibose markedly reduced level of serum NAG and BUN, and decreased the weight index of kidney. HE staining showed reduced kidney pathological changes after valibose treatment. The findings of the present study indicate that valibose may be a novel alpha-glucosidase inhibitor for the prevention from hyperglycemia in STZ-induced type 1 diabetes rats. And valibose might have a potential role for protecting against diabetic nephropathy during hyperglycemia.
Acetylglucosaminidase ; blood ; Animals ; Blood Glucose ; metabolism ; Blood Urea Nitrogen ; Cholesterol ; blood ; Creatinine ; blood ; Cyclohexanols ; pharmacology ; Diabetes Mellitus, Experimental ; blood ; pathology ; Diabetic Nephropathies ; prevention & control ; Enzyme Inhibitors ; pharmacology ; Fructosamine ; blood ; Glycoside Hydrolase Inhibitors ; Hyperglycemia ; prevention & control ; Hypoglycemic Agents ; pharmacology ; Kidney ; pathology ; Male ; Rats ; Rats, Sprague-Dawley ; Triglycerides ; blood ; Weight Gain ; drug effects