Effect of rhynchophylline on conditioned place preference on expression of NR2B in methamphetamine-dependent mice.

OBJECTIVE: To study the effect of rhynchophylline on N-methyl d-aspartate receptor subtype 2B subunit in hippocampus of Methamphetamine-induced conditioned place preference (CPP) mice. METHODS: Place preference mice models were established by methamphetamine; the expression of NR2B was observed by immunohistochemistry technique and Western blot. RESULTS: Methamphetamine (4mg/kg)-induced place preference mice model was successfully established; ketamine (15mg/kg), rhynchophylline (40mg/kg) and rhynchophylline (80mg/kg) can eliminate place preference; Immunohistochemistry showed that the number of NR2B-positive neurons in hippocampus was increased in the methamphetamine model group, whereas less NR2B-positive neurons were found in the ketamine group, low and high dosage rhynchophylline group. Western blot showed that the expression of NR2B protein was significantly increased in the model group, whereas less expression was found in the ketamine group, low and high dosage rhynchophylline group. CONCLUSIONS: NR2B plays an important role in the formation of methamphetamine-induced place preference in mice. Rhynchophylline reversed the expression of NR2B in the hippocampus demonstrates the potential effect of mediates methamphetamine induced rewarding effect.

FTIR determination of the degree of molar substitution for hydroxypropyl chitosan.

We developed and validated a novel Fourier transform infrared (FTIR) method to determine the degree of molar substitution (MS) for hydroxypropyl chitosan (HPCS) using nuclear magnetic resonance (1H NMR) as a reference, and investigated the factors influencing the MS assay. Through extensive screening of integration methods for candidate bands in the FTIR spectrum of HPCS using 20 HPCS samples with degrees of acetylation (DA) ranging from 0.003 to 0.139, we found that when using band area at 2970 cm-1 as a probe integral, the MS values obtained via the 1H NMR method exhibited linear correlations (R2 > 0.98) with at least 16 integral ratios derived from their FTIR spectra. The optimal reference bands with high reliability are located at 3440 cm-1 and 1415 cm-1, with R2 exceeding 0.99 and a MS range of 0.17-1.92. The band at 2875 cm-1 is less affected by the trace moisture present in HPCS samples than the others. The results of the method validation demonstrated a mean recovery of 98.9 ± 2.8 % and an RSD below 10 %, suggesting a simple, robust, and highly accurate and precise method. This method could be extendable for the determination of the MS of insoluble HPCS derivatives and other hydroxypropylated polysaccharides.

Effects of Exercise Training on the Phosphoproteomics of the Medial Prefrontal Cortex in Rats With Autism Spectrum Disorder Induced by Valproic Acid.

BACKGROUND: The key neural pathological characteristics of autism spectrum disorder (ASD) include abnormal synaptic plasticity of the medial prefrontal cortex (mPFC). Exercise therapy is widely used to rehabilitate children with ASD, but its neurobiological mechanism is unclear. METHODS: To clarify whether the structural and molecular plasticity of synapses in the mPFC are related to improvement in ASD behavioral deficits after continuous exercise rehabilitation training, we applied phosphoproteomic, behavioral, morphological, and molecular biological methods to investigate the impact of exercise on the phosphoprotein expression profile and synaptic structure of the mPFC in valproic acid (VPA)-induced ASD rats. RESULTS: Exercise training differentially regulated the density, morphology, and ultrastructure of synapses in mPFC subregions in the VPA-induced ASD rats. In total, 1031 phosphopeptides were upregulated and 782 phosphopeptides were downregulated in the mPFC in the ASD group. After exercise training, 323 phosphopeptides were upregulated, and 1098 phosphopeptides were downregulated in the ASDE group. Interestingly, 101 upregulated and 33 downregulated phosphoproteins in the ASD group were reversed after exercise training, and these phosphoproteins were mostly involved in synapses. Consistent with the phosphoproteomics data, the total and phosphorylated levels of the proteins MARK1 and MYH10 were upregulated in the ASD group and reversed after exercise training. CONCLUSIONS: The differential structural plasticity of synapses in mPFC subregions may be the basic neural architecture of ASD behavioral abnormalities. The phosphoproteins involved in mPFC synapses, such as MARK1 and MYH10, may play important roles in the exercise rehabilitation effect on ASD-induced behavioral deficits and synaptic structural plasticity, which requires further investigation.

[In situ intestinal absorption kinetics of berberine and jatrorrhizine from extractive Rhizoma Coptidis in rats].

OBJECTIVE: To investigate the in situ absorption kinetics of berberine (BER) and jatrorrhizine( JAT) at different intestine segments in rats. METHOD: The intestinal perfusion experiment was performed on rats in vivo to observe the effects of absorption sites and drug concentration on the intestinal absorption characteristics of BER and JAT. RESULT: The apparent absorption rate constants (Ka) of BER and JAT at duodenum, jejunum, ileum and colon were 0.1540, 0.1160, 0.9793, 0.6795 h(-1) and 0.0743, 0.0564, 0.0456, 0.0234 h(-1), respectively. The absorption of BER and JAT decreased according to the turn of duodenum, jejunum, ileum and colon. Compared to the lower segment, BER and JAT were better absorbed at the upper and middle segments of intestine in rats. The Ka of BER and JAT had no significant difference when the concentration of the extractive Rhizoma Coptidis was at 22-88 mg x L(-1). However, the absorption quantity of BER and JAT were proportional to the concentration respectively and the saturated phenomena were not observed. CONCLUSION: Both the BER and the JAT is can be absorbed in whole intestine and the results indicated that the absorption of BER and JAT compiled with the first order kinetics through passive diffusion mechanism.

Rhynchophylline Downregulates Phosphorylated cAMP Response Element Binding Protein, Nuclear Receptor-related-1, and Brain-derived Neurotrophic Factor Expression in the Hippocampus of Ketamine-induced Conditioned Place Preference Rats.

BACKGROUND: Addiction to ketamine is becoming a serious public health issues, for which there exists no effective treatment. Rhynchophylline (Rhy) is an alkaloid extracted from certain Uncaria species that is well known for both its potent anti-addictive and neuroprotective properties. Increasing evidence supports the contributions of cAMP response element binding protein (CREB), nuclear receptor-related-1 (Nurr1), and brain-derived neurotrophic factor (BDNF) in modulating neural and behavioral plasticity which was induced by addictive drugs. OBJECTIVE: To investigate the effects of Rhy on the behavior and the levels of phosphorylated CREB (p-CREB), Nurr1, and BDNF in the hippocampus of ketamine-induced conditioned place preference (CPP) rats. MATERIALS AND METHODS: CPP paradigm was used to establish the model of ketamine-dependent rats and to evaluate the effect of Rhy on ketamine dependence. The expressions of p-CREB, Nurr1, and BDNF were tested by Western blotting and immunohistochemistry. RESULTS: We observed that Rhy can reverse the behavior preference induced by ketamine CPP training. At the same time, expression of p-CREB, Nurr1, and BDNF, which was significantly increased by ketamine, was restored in the Rhy -treated group. CONCLUSION: This study indicates that Rhy can reverse the reward effect induced by ketamine in rats and the mechanism can probably be related to regulate the hippocampal protein expression of p-CREB, Nurr1, and BDNF. SUMMARY: P-CREB, Nurr1 and BDNF play an important role in the formation of ketamine-induced place preference in ratsRhynchophylline reversed the expression of p-CREB, Nurr1 and BDNF which was activated by ketamine in the hippocampusRhynchophylline demonstrates the potential effect of mediates ketamine induced rewarding effect. Abbreviations used: Rhy: Rhynchophylline; CREB: cAMP response element binding protein; Nurr1: Nuclear receptor-related-1; BDNF: Brain-derived neurotrophic factor; CPP: Conditioned place preference; NMDA: N-methyl-D-aspartic acid; METH: Methamphetamine; CNS: Central nervous system; PFA: Paraformaldehyde; GAPDH: Glyceraldehyde-3-phosphate dehydrogenase; LTP: long-term potentiation.

Effects of rhynchophylline on the hippocampal miRNA expression profile in ketamine-addicted rats.

In the past few years, ketamine, a noncompetitive NMDA antagonist, has been widely abused worldwide as a new type of synthetic drug, severely affecting the physical and mental health of ketamine abusers. Previous studies have suggested that rhynchophylline can alleviate drug abuse and reverse the conditioned place preference caused by the abuse. MicroRNAs (miRNAs) are important factors regulating gene expression and are involved in the drug addiction process. The hippocampus is a critical area in the brain involved in causing drug addiction. However, the hippocampal miRNA expression profile and the effects of rhynchophylline on miRNA expression during ketamine abuse have not been reported. Thus, this study analyzed the hippocampal miRNA expression profile during ketamine-dependence formation and the effects of rhynchophylline on the differential expression of miRNAs induced by ketamine. The results of microarray analysis suggested that the expression levels of miR-331-5p were significantly different among three groups (the control, ketamine, and ketamine + rhynchophylline groups). miR-331-5p levels were significantly decreased in the ketamine model group and were upregulated in the ketamine + rhynchophylline group. Bioinformatics analysis of miR-331-5p and the 3' UTR of nuclear receptor related 1 protein (Nurr1) identified binding sites and showed downregulation, and the overexpression of miR-331-5p in hippocampal tissues showed that miR-331-5p is a negative transcription regulatory factor of Nurr1. Interestingly, we found that the downstream protein of Nurr1, brain-derived neurotrophic factor (BDNF), showed identical expression trends in the hippocampus as Nurr1. However, the transcription of the protein upstream of Nurr1, cyclic adenosine monophosphate response element-binding protein (CREB), did not show any significant differences between the ketamine group and the ketamine + rhynchophylline group. However, after rhynchophylline intervention, p-CREB showed significant differences between the ketamine and the ketamine + rhynchophylline groups. In summary, miR-331-5p is a key regulatory factor of Nurr1, and rhynchophylline can participate in the process of resistance to ketamine addiction through the miR-331-5p/Nurr1/BDNF pathway or inhibition of CREB phosphorylation.

[Effect of Qingzhi soft capsule on blood lipid level and pathology of the fatty liver in hyperlipidemic rats].

OBJECTIVE: To observe the effects of Qingzhi soft capsule, a preparation of traditional Chinese medicine, on blood lipid level and the pathology of fatty degeneration of the liver in rats with hyperlipidemia. METHODS: SD rats were subjected to daily intragastric administration of a high-cholesterol emulsion (10 ml/kg) every morning to induce hyperlipidemia. The rats with established hyperlipidemia were then randomized into 4 groups and received every afternoon intragastric administration of high-dose (150 mg/kg) and low-dose (75 mg/kg) Qingzhi capsule, Xuezhikang (150 mg/kg, positive control ), and distilled water of the same volume (model group), respectively. A normal control group was also used in which the rats were given only distilled water in the same manner. After 21 days of treatment, all the rats were sacrificed for determining the serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels as well as the atherosclerosis index (AI). The liver of the rats was taken for examination of the pathology of fatty degeneration under microscope. RESULTS: The TC and TG levels in both of the Qingzhi capsule groups were significantly lower than those in the hyperlipidemic model group, but no significant differences were noted in HDL-C and LDL-C levels between the Qingzhi and model groups. AI was markedly lower in the two Qingzhi groups than in the model group. Pathological examination of the liver showed milder hepatic pathology of fatty degeneration in the Qingzhi groups than in the model group. CONCLUSION: Qingzhi soft capsule can modulate the blood lipid levels, ameliorate the hepatic pathology of fatty degeneration and lowers AI in in hyperlipidemic rats.