In silico investigation on the probable macromolecular drug targets involved in the anti-schizophrenia activity of Nardostachys jatamansi

Abstract Existing medications i.e. the antipsychotic drugs are known to be effective in treating only the positive symptoms of schizophrenia, while being ineffective on negative and cognitive symptoms of the disease. In addition, these medications cause extrapyramidal symptoms, forcing many patients towards natural medicine in the hope of minimizing the unwanted adverse effects. Nardostachys jatamansi is a medicinal plant that has been traditionally prescribed for various types of brain disorders. The active constituents of the plant have beneficial effects on the negative and cognitive symptoms of schizophrenia. This study was designed to identify the active constituents of Nardostachys jatamansi with the highest binding affinities for the key macromolecular drug targets involved in the pathophysiology of schizophrenia and thereby elucidate the possible mechanism of action. These targets are dopamine receptors, Gamma-aminobutyric acid receptors, N-methyl-D-aspartate receptors and Phosphodiesterase 10A. The results of molecular docking showed that, β-sitosterol, chlorogenic acid, oleanic acid and ursolic acid, displayed high binding affinity toward all the macromolecular drug targets. Ligands with steroid backbone and pentacyclic triterpene structure have been found to possess high binding affinity toward the dopamine receptor and phosphodiesterase 10A. While ligands with carbonyl group form stronger binding interactions with the N-methyl-D-aspartate receptor.

A novel screening system for Pseudomonas aeruginosa quorum sensing inhibitors / 生物工程学报

Quorum sensing is an important gene regulatory mechanism in Pseudomonas aeruginosa and controls the expression of numerous virulence factors. We designed and constructed a screening system for quorum-sensing inhibitors. We developed the system by using the lasI and rhlA promoters fused with promoterless sacB as reporters. Using this system we screened a number of Chinese herb extracts, and identified three herb extracts containing inhibitors to the quorum-sensing system and to its regulated genes. The screening system developed was highly efficient and sensitive. It could serve as a useful tool to identify herb compounds that block infections but unlikely render antibiotic resistance in pathogens.

[Anxiolytic effects of Valepotriates extracted from Valeriana officinalis L. in rats]

Anxiety is a common disorder attacking many people in the society and often accompanied by physiological sensations such as tachycardia, chest pain, shortness of breath, insensitivity, and so on. The purpose of present study was to characterize the putative anxiolytic-like effects of valepotriates [dichloromethane extracts of valerian] using the elevated plus maze [EPM] in rats. This was an experimental study carried out at Biology Department of Azad Islamic University in Karaj [Iran] in 2006. Valepotriates was dissolved in DMSO and orally administered at different doses to adult male Wistar rats, 0.5, 1.5 and 3 hours before behavioral evaluation in an EPM. Control rats were treated with an equal volume of DMSO. Data were evaluated using SPSS and variance analysis. Single treatment with valepotriates at two concentrations of 0.1, and 0.2 g/kg caused a statically significant increased time-spent and arm entries into open arms of EPM compared to control group [p<0.05]. However, animal's locomotor activity found to be unchanged. Based on our data, it seems that valepotriates to have a potential as an effective anxiolytic agent

role of herbal drugs in psychiatry

The therapeutic uses of various herbal drugs for psychiatric disorders have a long tradition in India, China and other Asian cultures. The unwanted side effects of synthetic psychotropics have contributed to the increasing interest in phytotherapeutic agents. Improved understanding of appropriate and safe uses of naturally occurring substances as psychotropic agents will greatly contribute to global mental care. An important objective of this paper is to stress the scientific evidence, supporting the use of natural products in psychiatry. Traditional Ayurvedic drugs used in psychiatry is briefly discussed. Knowledge of the properties of these therapies supported by clinical evidence, efficacy and safety profile can improve the care of psychiatric patients