Xiaoguang Lu

The effects of the Chinese medicine ZiBu PiYin recipe on the hippocampus in a rat model of diabetes-associated cognitive decline: a proteomic analysis

Aims/hypothesisIncreasing evidence suggests that diabetes is associated with an enhanced risk of cognitive decline. The precise mechanisms underlying diabetes-associated cognitive decline (DACD) remain unclear. Here we investigated the molecular changes associated with DACD using a comparative proteomics study of hippocampus in a rat model of type 2 diabetes. In addition, we tested the effects of the Chinese medicine ZiBu PiYin recipe (ZBPYR) on DACD.MethodsThe hippocampus was dissected from control, diabetic and diabetic rats treated with ZBPYR (DM/ZBPYR). Soluble proteins were separated using fluorescence-based difference gel electrophoresis. Protein spots were visualised with fluorescent dyes and spot density was compared between each pair of groups. Proteins of interest were identified using mass spectrometry. Proteins of specific interest were also tested by western blot and real-time PCR analysis.ResultsWe found 13 spots that were altered between control and diabetes groups, and 12 spots that were changed between diabetes and DM/ZBPYR groups. The identities of nine proteins were determined by mass spectrometry. The identified proteins were largely involved in energy metabolism, cytoskeleton regulation and oxidative stress. The protein alterations observed in the diabetes group were ameliorated to varying degrees following ZBPYR treatment.Conclusions/interpretationThe protein changes identified in hippocampus from a rat model of type 2 diabetes suggest that specific cellular alterations contribute to DACD. The Chinese medicine ZBPYR was found to affect multiple targets and partially repaired the original cellular balance. This study may provide important insights into the molecular events underlying DACD and allow the identification of novel therapeutic targets.

The effects of Zibu Piyin Recipe components on scopolamine-induced learning and memory impairment in the mouse.

ETHNOPHARMACOLOGICAL RELEVANCEnThe Zibu Piyin Recipe (ZBPYR) is derived from Zicheng Decoction, a traditional Chinese medicine formula recorded in the book of Bujuji, written by Wu Cheng in the Qing dynasty and used for clinical treatment of amnesia. Our aim was to study the effects of Zibu Piyin Recipe (ZBPYR) fractions on scopolamine-induced learning and memory impairment in the mouse.nnnMATERIALS AND METHODSnCrude extracts were prepared using various solvents, and individual fractions produced following D101 macroporous resin column chromatography. The passive avoidance task, step down test and Morris water maze test were then performed in mice for the evaluation of learning and memory alterations. The effective fractions were then analyzed using GC-MS and polysaccharide measurement methods, respectively.nnnRESULTSnThe treatment group latency for the alcohol precipitation from water part (EP) and 95% ethanol part (95%E) following D101 macroporous resin column chromatography was significantly prolonged when compared to that of the scopolamine treated groups for both the passive avoidance task and step down test. In the Morris water maze tests, treatment with EP and 95%E resulted in a significantly shorter escape latency time (from the fourth day and the second day) and swimming distance (on the third day and from the third day) in scopolamine-induced mice. In the memory retention test, treatment with EP and 95%E dramatically shortened the latency to cross platform location and increased the numbers of platform location crosses in the scopolamine-induced mice. The polysaccharide content in EP was determined to be 69.79%. The 95%E was found to mainly contain asarone, α-cadinol, isocalamendiol, 2,4,7,14-tetramethyl-4-vinyl-tricyclo[5.4.3.0(1,8)]tetradecan-6-ol, 3-isopropyl-6,7-dimethyltricyclo[4.4.0.0(2,8)]decane-9,10-diol, 2-methyl-9-(prop-1- -en-3-ol-2-yl)-bicyclo[4.4.0]dec-2-ene-4-ol, diepicedrene-1-oxide, 7-methoxy-6-(3- -methyl-2-oxobutyl)-2H-1-benzopyran-2-one and diisooctyl phthalate when assessed using GC-MS analysis.nnnCONCLUSIONnThese findings suggest that the polysaccharide and volatile oil present in ZBPYR exhibit ameliorating effects on scopolamine-induced memory dysfunction.

Endoplasmic Reticulum Stress Impairs Insulin Receptor Signaling in the Brains of Obese Rats

The incidence of obesity is increasing worldwide. It was reported that endoplasmic reticulum stress (ERS) could inhibit insulin receptor signaling by activating c-Jun N-terminal kinase (JNK) in the liver. However, the relationship between ERS and insulin receptor signaling in the brain during obesity remains unclear. The aim of the current study was to assess whether ERS alters insulin receptor signaling through the hyper-activation of JNK in the hippocampus and frontal cortex in the brains of obese rats. Obesity was induced using a high fat diet (HFD). The Morris water maze test was then performed to evaluate decreases in cognitive function, and western blot was used to verify whether abnormal insulin receptor signaling was induced by ERS in HFD rats exhibiting cognitive decline. In addition, to determine whether ERS activated JNK and consequently impaired insulin receptor signaling, SH-SY5Y cells were treated with the JNK inhibitor, SP600125, followed by tunicamycin or thapsigargin, and primary rat hippocampal and cortical neurons were transfected with siRNA against IRE1α and JNK. We found that the expression of phosphorylation of PKR-like kinase (PERK), phosphorylation of α subunit of translation initiation factor 2 (eIF2α), and phosphorylation of inositol-requiring kinase-1α (IRE-1α) were increased in the brains of rats with HFD when compared with control rats. The level of serine phosphorylation of insulin receptor substrate-1 (IRS-1) was also increased, while protein kinase B (PKB/Akt) was reduced. ERS was also found to inhibit insulin receptor signaling via the activation of JNK in SH-SY5Y cells, primary rat hippocampal, and cortical neurons. These results indicate that ERS was increased, thereby resulting in impaired insulin receptor signaling in the hippocampus and frontal cortex of obese rats.

The effect of Chinese herbal medicine on non-biliogenic severe acute pancreatitis: a systematic review and meta-analysis.

ETHNOPHARMACOLOGICAL RELEVANCEnMore and more clinicians and researchers have realized that clinical trials are necessary to define clinical efficacy effect. Even though the number has been substantially growing for the past years, the finished and reported trials are limited. Nevertheless, those documented trials are important and precious, and comprehensive evaluation and analysis of them are warranted at current stage. Our goal was to evaluate the effect of Chinese herbal medicine (CHM) on non-biliogenic severe acute pancreatitis (SAP) by conducting a systematic review and meta-analysis of prospective randomized controlled studies.nnnMETHODSnRelevant studies were identified by PubMed, Cochrane Library, EMBASE, China Biomedical Database web (CBM), China National Knowledge Infrastructure Databases (CNKI), and Wanfang database up to 2014.Reference lists of retrieved articles were also reviewed. Two reviewers independently assessed studies for inclusion and extracted data. The main outcome data of trials were analyzed by using RevMan5.2. Odds ratio (OR) or mean difference (MD) with a 95% confidence interval (CI) was used as effect measure. Either a fixed or a random-effect model was used to evaluate the effect of CHM on non-biliogenic SAP.nnnRESULTSnTwenty two prospective randomized controlled studies involving 1388 participants were included in the meta-analysis. CHM was tested to be more effective than reference group: Mortality [OR: 0.43, 95% CI (0.29, 0.64)], overall efficiency [OR: 4.0, 95% CI (2.72, 5.89)], operability [OR: 0.313, 95% CI (0.21, 0.46)], rate of complications [OR: 0.37, 95% CI (0.27, 0.50)], Length of hospitalization [MD: -9.70, 95% CI (-12.88, -6.51)] compared with reference group.nnnCONCLUSIONSnNo serious adverse events were reported. This meta-analysis provides evidence suggesting that CHM seems to be an effective and safe treatment for people with non-biliogenic severe acute pancreatitis (SAP). However, the poor methodological quality of most of the trials means that we may be unable to reach a definitive conclusion. Hence, the effect of CHM in the treatment of non-biliogenic SAP warrants rigorously designed, multicentre, large-scale trials with higher quality worldwide.

Rat hippocampal proteomic alterations following intrahippocampal injection of amyloid beta peptide (1–40)

Amyloid beta peptide 1-40 (Aβ(1-40)) is closely associated with the progressive neuronal loss and cognitive decline observed in Alzheimers disease (AD). This study aimed to establish a proteomic strategy for the profiling of AD tissues for disease-specific changes in protein abundance. Intrahippocampal injection of Aβ(1-40) induced spatial memory and learning decline in rats. Proteomic analysis revealed the changes in protein expression in the rat hippocampus treated with Aβ(1-40). Four proteins of interest which was in abundance was significantly altered in Aβ(1-40)-treated rats were identified by peptide mass fingerprint (PMF). These proteins corresponded to synapsin Ib, protein disulfide-isomerase A3 precursor, tubulin β chain and ATP synthase β subunit. Our results provide new insights into the relationship between Aβ and the pathogenesis of AD, and suggest potential targets for the therapy of AD.

Role of the SNK-SPAR pathway in the development of Alzheimer's disease

Alzheimers disease (AD) is characterized by the presence of senile plaques and neurofibrillary tangles in the brain. The beta‐amyloid peptide (Aβ) is the primary constituent of the senile plaques, and has been proposed to be a key contributor to the neurodegeneration observed in AD. The molecular mechanisms underlying dendritic spine damage that is induced by Aβ toxicity in AD patients remain largely unknown. It has been suggested previously that the SNK‐SPAR signaling pathway is involved in activity‐dependent remodeling of synapses. The relationship between the SNK‐SPAR pathway and Aβ‐induced excitotoxicity, however, is poorly understood. The present study investigated the effects of bilateral intrahippocampal injection of Aβ peptide 1–40 (Aβ1–40) on learning and memory in the rat, and explored the mechanisms underlying the effects of this injection. We reported that bilateral injection of Aβ1–40 in rats resulted in impaired performance in the step‐down passive avoidance and Morris water maze tasks. Then we examined mRNA and protein expression levels in the different brain regions one week after injection with Aβ1–40 and found that the SNK‐SPAR signaling pathway was possibly involved in dendritic spine damage in the different brain regions of Aβ‐treated rats. These results demonstrate that the SNK‐SPAR pathway may possibly play a crucial role in Aβ‐induced excitotoxic damage in the central nervous system by regulating synaptic stability.

Effects of Zibu Piyin Recipe (滋补脾阴方药) on SNK-SPAR pathway in neuron injury induced by glutamate

ObjectiveTo investigate the relationship between the excitotoxicity and serum-inducible kinase (SNK) and spine-associated Rap GTPase-activating protein (SPAR) pathway in primary hippocampal neuron injury induced by glutamate and furthermore, to explore the molecular mechanism of neuroprotection of Zibu Piyin Recipe (滋补脾阴方药, ZBPYR) and the relationship between ZBPYR and the morphological regulation of dendritic spines.MethodsThe serum containing ZBPYR was prepared by seropharmacology. Reverse transcription and polymerase chain reaction (RT-PCR) was used to detect the expression of mRNA for SNK, SPAR, postsynaptic density protein 95 (PSD-95) and N-methyl-D-aspartate (NMDA) receptor subunits (NR1, NR2A and NR2B) in primary rat hippocampal neuron cultures after pretreatment with 10 μmol/L glutamate and ZBPYR serum.ResultsZBPYR serum pretreatment resulted in a significant down-regulation of glutamate-induced SNK mRNA expression (P<0.05). Significant up-regulation was seen on the mRNA expression of SPAR and PSD-95 (P<0.05). All these changes were dose-dependent. The mRNA expression of NR1, NR2A and NR2B was down-regulated to different degrees (P<0.05).ConclusionThe mechanism of effect of ZBPYR on glutamate-induced excitotoxicity may be related to the regulation of SNK-SPAR signal pathway. ZBPYR may play a role in protecting and maintaining the normal morphology and structure of dendritic spines, which may be achieved by inhibiting the excessive activation of NMDA receptors.

Effects of pyruvate-enriched peritoneal dialysis solution on intestinal barrier in peritoneal resuscitation from hemorrhagic shock in rats

BACKGROUNDnTo investigate protective effects of pyruvate-enriched peritoneal dialysis solution (P-PDS), compared with lactate-PDS (L-PDS), on the intestinal mucosal barrier in peritoneal resuscitation (PR) from severe hemorrhagic shock (HS) in rats.nnnMATERIALS AND METHODSnFifty male SD rats were randomly divided into five groups (n = 10): group sham, group control (HS without fluid resuscitation), group intravenous resuscitation (IVR) (HS with IVR only), group L-PDS (HS with i.v. infusion plus PR with L-PDS), and group P-PDS (HS with i.v. infusion plus PR with P-PDS). HS was induced by hemorrhage with mean arterial pressure 40 mm Hg for 60 min. In three groups with fluid rehydration, IVR included shed blood and dl-lactate Ringer solution equal to two times the volume of shed blood during 60 min; in two groups with PR, 20 mL of L-PDS, or P-PDS were infused when i.v. infusion started after HS into the peritoneal cavity in 20 min, respectively. Blood samples were taken for determinations of pH, base excess, PaCO2, PaO2, and D-LA 60 min post fluid resuscitation. After rats were sacrificed, a segment of intestine was harvested for the detection of expressions of intestinal barrier proteins: zonula occludens-1 (ZO-1) and phosphorylated vasodilator-stimulated phosphoprotein (p-VASP) by Western blot and immunohistochemistry. Intestinal morphologic alterations were also observed.nnnRESULTSnBlood pH, base excess, and PaO2 were higher, whereas PaCO2 and D-LA were lower in group P-PDS than in other three HS groups (P < 0.05 and P < 0.01, respectively). Severe acidosis was nearly corrected in group P-PDS. Intestinal barrier proteins ZO-1 and p-VASP were significantly preserved in group P-PDS than in group L-PDS (P < 0.05) although they were improved in group L-PDS in comparison with other two HS groups (P < 0.05 or P < 0.01). Expressions of barrier proteins by Western blotting in group P-PDS were reversed to normal. The score of intestinal epithelial damage index was reduced in group L-PDS, compared with other two HS groups (P < 0.05), however, it was significantly lower in group P-PDS than in group L-PDS (P < 0.05).nnnCONCLUSIONSnPyruvate was superior to lactate in PDS in the correction of severe acidosis with PR. P-PDS was more preservative of expressions of intestinal ZO-1 and p-VASP and mucosal barrier function, compared with L-PDS in PR from severe HS in rats.

Dai-Huang-Fu-Zi-Tang alleviates pulmonary and intestinal injury with severe acute pancreatitis via regulating aquaporins in rats

BackgroundDai-Huang-Fu-Zi-Tang (DHFZT) is a famous traditional Chinese prescription with intestinal obstruction, acute pancreatitis and cholecystalgia for thousands of years. Our previous work found that DHFZT could act against pulmonary and intestinal pathological injury in rats with severe acute pancreatitis (SAP). But the underlying mechanism has not been fully elucidated. The aim of present study was to investigate whether DHFZT could relieve pulmonary and intestinal injury by regulating aquaporins after SAP induced by sodium taurocholate in rats.MethodsForty of SD rats were used for dose dependant experiments of DHFZT.Accurate-mass Time-of-flight liquid chromatography-mass spectrometry was used for qualitative screening of chemical compositions of DHFZT. Twenty-four rats were randomly divided into 3 groups: sham group (nxa0=xa08), model group (SAP, nxa0=xa08), DHFZT group (SAP with DHFZT treatment, nxa0=xa08). SAP models were established by retrograde injections of 5% sodium taurocholate solutions into rat pancreaticobiliary ducts. Blood samples were taken at 0, 12, 24, 48xa0h post-operation for detecting serum amylase, lipase, endotoxin, TNF-α, IL-6 and IL-10. Protein expression and location of aquaporin (AQP)1, 5, 8 and 9 were assessed by immunohistochemistry, western blot and immunofluorescence respectively.ResultsThe study showed that 27 kinds of chemical composition were identified, including 10 kinds in positive ion mode and 17 kinds in negative ion mode. The results showed that AQP1, AQP5 of lung, and AQP1, AQP5, AQP8 of intestine in model group were significantly lower than that of sham group (Pxa0<xa00.05), and which were obviously reversed by treatment with DHFZT. In addition, protein levels of pro-inflammatory cytokines such as TNF-α, IL-6 and endotoxin in peripheral blood were significantly suppressed by DHFZT, and that anti-inflammatory cytokine like IL-10 was just opposite. Finally, we also noted that DHFZT reduced serum levels of amylase, lipase and endotoxin, and also improved edema and pathological scores of lung and intestine after SAP.ConclusionsDHFZT ameliorated the pulmonary and intestinal edema and injury induced by SAP via the upregulation of different AQPs in lung and intestine, and suppressed TNF-α, IL-6 expression and enhanced IL-10 expression.

Sepsis-induced impairment of neutrophil chemotaxis on a microfluidic chip

This study aimed to design a microfluidic chip to measure neutrophil chemotaxis, which is a convenient assay to assess the severity and prognosis of sepsis, and to study the mechanisms involved in the variation of neutrophil chemotaxis. Neutrophil chemotaxis was investigated in this microfluidic device by measuring the migration speed of neutrophils following the LPS concentration gradient stimulus. Neutrophils of 32 sepsis patients were divided into three groups according to the seriousness of physician-diagnosed sepsis, and 12 healthy individuals served as controls. Statistical significance was set at an alpha value of P<0.05. Neutrophil chemotaxis was significantly decreased following the seriousness of sepsis. By contrast, in septic neutrophils, the expression of TLR2 was significantly increased, whereas the expression of CXCR2 was significantly decreased. Neutrophil chemotaxis in sepsis was significantly reduced as compared to healthy individuals. We speculated that impaired neutrophil chemotaxis in sepsis was probably mediated by the TLR2-CXCR2 pathway.