Metabonomic Study On The Acute And Chronic Stresses And Drug Intervention

Stress is a functional status of body in responding to intensive stimuli including wound, poisoning, cold/hot, fatigue, emotional strain, scare, etc., when the secretion of stress hormones (e.g., cortisol, ACTH) raise rapidly and largely, which caused series of variances in adaptability and resistivity of biosystem. Acute stress reaction is a process of self-limitaion that means once the effects of stressor stopped the retrieving homeostasis could terminate the stress procedure. However, if the effects of stressor act over intensive, highly secreted hormones would bring body multi-diseases, such as depression, dysmnesy, stress ulceration, mental aberration and hypoimmunity. Most of the existing investigations of stress were carried out with the target of blood and tissue, which may lead to agitation and the process itself, may serve as a source of stimulation which might cause another stress, hence brought unpredictable interferences and misleading to the result. Stress reaction is a systemic and dynamic process which needs a systemic and dynamic research tool to evaluate and investigate it.Metabonomics or metabolomics is the quantitative measurement of the multiparametric time-related metabolic responses of a complex (multicellular) system to a pathophysiological intervention or genetic modification. Thus metabonomics seeks to assess the global system level homeostatic and pathological responses to interventions or stressors. Metabolome is the result of whole expression of proteome, transcriptome, genome which reflect the biochemical status of tissues directly. Urine sampling is non-invasive and commonly used for in vivo metabolic profiling. It is very important for the illustration of the complicated life systems because of the sensitive response of the changes of the philological and pathological status of the life. The main characteristics of metabonomics are the high-throughput experiment and calculation. Metabonomics has become an important hotspot for the research of disease and healthy in the world now. In this current article, we tried to employ the soul and method of metabonomics to rediscover stress and relative diseases.Acute stress may trigger systemic biochemical and physiological changes in living organisms, leading to a rapid loss of homeostasis, which can be gradually reinstated by self-regulatory mechanisms and/ or drug intervention strategy. However, such a sophisticated metabolic regulatory process has so far been poorly understood, especially from a holistic view. Urinary metabolite profiling of Sprague-Dawley rats exposed to cold temperature (-10°C) for 2 h using derivatized GC/MS in conjunction with modern multivariate statistical techniques revealed drastic biochemical changes as evidenced by fluctuations of urinary metabolites and demonstrated the protective effect of ginsenosides in ginseng extracts on stressed rats. The metabonomics approach enables us to visualize significant alterations in metabolite expression patterns as a result of stress-induced metabolic responses and post-stress compensation, and drug intervention. Several major metabolic pathways including catecholamines, glucocorticoids, the tricarboxylic acid (TCA) cycle, tryptophan (nicotinate), and gut microbiota metabolites were identified to be involved in metabolic regulation and compensation required to restore homeostasis. The protective actions of ginsenosides were verified by reduced variations of endogenous metabolites caused by cold stress.A rapid analytical method for quantifying 17 ginsenosides in rat urine by ultra performance liquid chromatography (UPLC) coupled to electrospray ionization mass spectrometry (ESI–MS) is described. All analytes were extracted by solid phase extraction optimized to obtain good recovery and quantified using digoxin as an internal standard. ESI–MS was optimized for different cone voltages at positive ionization mode to allow simultaneous analysis of all analytes in a relatively short time. Qualitative methodological considerations, including the linear range, precision, limit of quantification, limit of detection, recovery and sensitivity are also provided. Some ginsenosides variances were found in urine of cold exposed rats by employing the newly-built analytical method. It could be concluded that cold stress may affect ginsenosides absorption and metabolism via oral administration.A chronic unpredictable mild stress model of depression was employed for urine metabonomic study. Male Sprague-Dawley rats (simultaneous with saline, ginsenosides, St. John's Wort extracts and Clomipramine) were exposed to an unpredictable sequence of mild stressors. Bodyweight, daily food intake, open-field test, immobility time, sucrose consumption were investigated during the whole procedure. Weight of adrenal, thymus and spleen, relative index, plasma ACTH and serum corticosterone were also studied at the end time of chronic stress. Behavior tests indicated that rats of model group growing to an anhedonia symptom which is similar to the feature of human depression. The administration of ginsenosides, St. John's Wort extracts and Clomipramine could release the symptoms to some extents. Metabonomic study on urine was carried to indicate that unpredictable mild chronic stress may cause variances of endogenous metabolites in rat urine, in which, some of these differential compounds on day 9 consisted with those caused by acute cold stress, others of day 27 showed close relation with depression, which were convinced by brain tissue metabonomic study.Our results provide new insight into urinary metabolic variances effected by stress, highlight mechanisms of metabolic regulation at a holistic level in response to acute cold stress and chronic stress, and reveal exogenous protective regulation of medicines.