ABSTRACT
Objective: Berberine, a cationic alkaloid first isolated in 1917, has been approved by the China Drug Administration for decades. Accumulating evidence demonstrated its antidepressant-like activities in vivo. Our previous study has shown that chronic stress leads to the upregulation of miR-34a in the hippocampus of mice. This study aims to evaluate the underlying miR-34a mediated mechanism of berberine in chronic stress-induced depression in mice. Methods: In the present study, mice were administered with berberine during chronic stress. Levels of miR-34a, dendritic density, mitochondrial morphology, and neurogenesis were assessed in the hippocampus. Subsequently, miR-34a agomir was used as a pharmacological intervention for the investigation of berberine. Results: The results showed that berberine reversed the decrease in sucrose preference and the increase in latency to feed without altering total food consumption. Furthermore, chronic stress-induced overexpression of miR-34a decreased synaptotagmin-1 and Bcl-2 levels, thereby impairing spinal morphology, mitochondria and neurogenesis. Berberine inhibited miR-34a expression, in turn restored synaptotagmin-1 and Bcl-2 levels, and thus improved spinal morphology, mitochondria and neurogenesis in the hippocampus. However, the improvements induced by berberine were totally blocked by the pretreatment of miR-34a agomir, which caused the elevation of miR-34a levels in the hippocampus. Conclusion: This finding demonstrated that miR-34a downregulation was involved in the antidepressant-like effects of berberine in mice exposed to chronic stress.
ABSTRACT
The present study was designed to isolate and evaluate the antibacterial activity of the compounds from the whole plant of Euphorbia helioscopia L.. Various chromatographic techniques were used to isolate and purify the compound. The structure of the compound was elucidated on basis of spectral data ((1)H NMR, (13)C NMR, (1)H-(1)H COSY, HSQC, HMBC, NOESY, IR, and HR-ESI-MS). A new jatrophone-type diterpenoid (14α,15β-diacetoxy-3β-benzoyloxy-7β-nicotinoyloxy-9-oxo-jatropha-5E,11E-diene), named euphoheliosnoid E (1), was isolated from the whole plant of E. helioscopia L. Compound 1 showed significant anti-microbial activity against oral pathogens.
Subject(s)
Anti-Infective Agents , Pharmacology , Diterpenes , Chemistry , Pharmacology , Euphorbia , Chemistry , Molecular Structure , Mouth Diseases , Microbiology , Niacin , Chemistry , Pharmacology , Plant Extracts , Chemistry , PharmacologyABSTRACT
Arginine Deiminase(ADI) was purified to homogeneity using ammonium sulfate precipitation,Q-Sepharose Fast Flow anion exchange chromatography and SephadexG-75 gel filtration chromatography. This purification protocol resulted in a 34.5-fold purification of ADI with 31.4% final yield. A molecular weight of about 190 kD determined by native gradient polyacrylamide gel electrophoresis. The enzyme has only one kind of 46 kD subunit determined by SDS-PAGE. Combining the results from the two kinds of electrophoresis,the authors deduce that the enzyme may be a tetramer. The optimum pH and temperature for lipolytic activity of ADI was pH 6.5 and 50℃,respectively. It was extremely stable at 45℃ and retained 97.9% of its original activity for 30 min. The stability declined rapidly as soon as the temperature rose over 50℃. ADI was highly stable in the pH range from pH 5-8. ADI acted on L-arginine but not on D-arginine. ADI catabolism was dependent on metal ions. At their adequate concentration,Mn2+,Mg2+ and Co2+ were the effective promoter,while superfluous Zn2+and Co2+ inhibited ADI activity. L-citrulline did not act on ADI,but L-ornithine inhibited ADI activity. The degradation of L-arginine with ADI catalysis was according to simple Michaelis-Menten equation. The Michaelis constant was 3.2686 mmol/L and the maxi-mum velocity was 2.44 ?mol/min.