Expression of miRNAs in Serum Exosomes versus Hippocampus in Methamphetamine-Induced Rats and Intervention of Rhynchophylline.

OBJECTIVE: To compare the expressions of miRNAs (microRNAs) in serum exosomes and in hippocampus and to provide insights into the miRNA-mediated relationship between peripheral and central nervous systems in the presence of methamphetamine. METHODS: Published results on conditioned place preference (CPP) in rats conditioned by methamphetamine were replicated. The expressions of miRNAs in serum exosomes and hippocampus were determined by gene-chip sequencing. We then predicted the potential target genes of selected, differentially expressed (DE) miRNAs and then carried out functional analysis of these target genes. We also verified our results by RT-qPCR. RESULTS: Methamphetamine reward could greatly increase the activity time and distance in the intrinsically nonpreferred side of the behavioral apparatus compared with control rats (P < 0.01). Rhynchophylline treatment significantly counteracted these changes (P < 0.01). Methamphetamine-induced CPP upregulated 23 miRNAs (log2 fold change [FC] > 1, P < 0.01) in serum exosomes, whereas rhynchophylline treatment could downregulate these miRNAs (log2 FC < -1, P < 0.01). Analysis of hippocampal miRNAs profiles found 22 DE miRNAs (log2 FC > 1 or <-1, P < 0.01). When methamphetamine induced CPP, 11 of those miRNAs were upregulated, whereas rhynchophylline treatment could downregulate these miRNAs. The other 11 miRNAs behaved in the opposite way. We selected six DE miRNAs from each of serum exosomes and hippocampus for target gene prediction and functional analysis. We found that, in both, the DE miRNAs and their target genes may be related to neuronal information transmission and synaptic transmission. CONCLUSIONS: Rhynchophylline blocked the alteration of behavior and the expression of some DE miRNAs induced by methamphetamine. The biological functions of these DE miRNAs target genes are correlated between serum exosomes and hippocampus. As to these biological processes and pathways which are involved in the development of addiction at multiple stages, we speculate that these DE miRNAs in serum exosomes and hippocampus are closely related to methamphetamine addiction.

[Changes in plasma pharmacokinetics and urinary excretion characteristics before and after combined administration of Ephedrae Herba-Gypsum Fibrosum].

In this study, UPLC-MS/MS was adopted to determine the contents of five ephedrine alkaloids (Norephedrine, Norpseudoephedrine, Ephedrine, Pseudoephedrine, Methylephedrine) in plasma and urine in rats after the combined administration of Ephedrae Herba-Gypsum Fibrosum and calculate relevant pharmacokinetic parameters, in order to discuss the effect of the combined administration of Ephedrae Herba-Gypsum Fibrosum on plasma pharmacokinetics and urinary excretion characteristics. According to the results, after being combined with Gypsum, the five ephedrine alkaloids showed similar pharmacokinetic changes, such as shortened t(max), accelerated absorption rate, but reduced AUC(0-t) and V(z)/F, which may be related to the increase in urine excretion. Besides, Gypsum was added to enhance C(max) of Pseudoephedrine and prolong MRT(0-t) of Methylephedrine, so as to enhance the anti-asthmatic effect of Ephedrae Herba and resist the toxic effect of Norephedrine and Ephedrine. This study proved the scientific compatibility of Ephedrae Herba-Gypsum Fibrosum and provided a reference for studies on the prescription compatibility regularity and relevant practices.

Pharmacokinetic comparisons of five ephedrine alkaloids following oral administration of four different Mahuang-Guizhi herb-pair aqueous extracts ratios in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Herba Ephedra (Mahuang in Chinese), is derived from dried Ephedra sinica Stapf stems and has been widely used to treat the common cold, coughs, asthma, and edema for thousands of years. The Mahuang-Guizhi herb-pair is a famous formula composed of Mahuang and Ramulus Cinnamomi (Guizhi in Chinese, the dried twig of Cinnamomum cassia Presl.), used to improve pharmacological effects and reduce toxicity. In order to investigate the influence of Mahuang-Guizhi herb-pair ratios on bioavailability, the plasma pharmacokinetics profiles of five ephedrine alkaloids were compared following oral administration of four different ratios to rats. MATERIALS AND METHODS: Sprague-Dawley rats were randomly assigned to four groups and orally administered Mahuang-Guizhi (ratios 3:0; 3:1; 3:2; 3:4, w/w). Assays for five ephedrine alkaloids (ephedrine, pseudoephedrine, methylephedrine, norephedrine, and norpseudoephedrine) were developed and validated using ultra-high-performance liquid chromatography tandem mass spectrometry coupled with liquid-liquid extraction. RESULTS: Key pharmacokinetic parameters of the five ephedrine alkaloids (maximal plasma concentration, mean residence time, and half-life) were significantly different (p<0.05) after oral administration of Mahuang-Guizhi herb-pair ratios, as compared to those of Mahuang. CONCLUSION: Ephedrine alkaloid pharmacokinetic differences in rat plasma could help explain previous findings of pharmacological and toxicity differences between Mahuang and Mahuang-Guizhi herb-pair preparations. These results could facilitate future studies to increase the efficacy and decrease the toxicity of Mahuang and Guizhi.

[Pharmacokinetic and Tissue Distribution Study of Ephedrae Herba and Herbal Pair of Ephedrae Herba-Atractylodis Macrocephalae Rhizoma in Rats].

OBJECTIVE: Five kinds of Ephedra alkaloids (NME, NMP, E, PE and ME) in Ephedrae Herba extracts and Ephedrae Herba-Atractylodis Macrocephalae Rhizoma herbal pair extracts of plasma pharmacokinetic and tissue distribution study in rats were carried out, to discuss the changes of Ephedrae Herba compatibility with Atractylodis Macrocephalae Rhizoma before and after METHODS: HPLC- MS method was used and the condition was as flollows: ZORBAX SB-C18 column (100 mm x 2.1 mm, 3.5 µm), column temperature of 35 °C, mobile phase of ACE-0.1% formic solution in gradient elution mode, flow rate at 0.4 mL/min; MRM positive ion detection mode. RESULTS: The distribution trends of Ephedra alkaloids were changing in plasma and tissues of rats after Ephedrae Herba compati- bility with Atractylodis Macrocephalae Rhizoma. CONCLUSION: Ephedrae Herba compatibility with Atractylodis Macrocephalae Rhizoma may increase drug efficacy and reduce the toxicity of Ephedra alkaloids at the same time.