The bio-active components of the Mongolian medicine Horcha-6 and therapeutic mechanism in the rat migraine model

Background:The active components of Horcha-6 were identified using liquid chromatography with tandem mass spectrometry.Also,we investigated the potential mechanisms that explain why Horcha-6 may be effective in treating migraines through the use of network pharmacology and a rat migraine model.Methods:After identifying the active components of Horcha-6,the corresponding genes of the active components’target were obtained from the Universal Protein database,and a“compound-target-disease”network was constructed using Cytoscape 3.9.0 software.For the in vivo experiments,nitroglycerin was injected intraperitoneally into rats to create a migraine model.Pre-treatment with Horcha-6 was administered orally for 14 days,and rats were subjected to migraine-related behavior tests.RNA sequencing was performed to identify the gene expression regulated by Horcha-6 in the trigeminal nerve.Results:A total of 903 chemical components of Horcha-6 have been collected in the liquid chromatography with tandem mass spectrometry.We discovered 55 of the Horcha-6 bio-active components that were evaluated based on their Percent Human Oral Absorption(≥30%)and DL values(≥0.185)on the traditional Chinese medicine systems pharmacology database.The“compound-target-disease”network contained 163 intersection targets with the migraine state.Gene Ontology analysis indicated that these components significantly regulated the immune response,vascular function,oxidative stress,etc.When Kyoto Encyclopedia of Genes and Genomes enrichment analysis was performed,we observed that most of the target genes were significantly enriched in the inflammation and neuro-related signaling pathway,toll-like receptor signaling pathway,neuroactive ligand-receptor interaction,etc.These predictions were further demonstrated via in vivo animal model experiments.The RNA sequencing results showed that 41 genes were down-regulated(P<0.05)and 86 genes were up-regulated(P<0.05)in the Horcha-6 treated group compared with the untreated group.Those genes were mainly involved in neuromodulation,vascular function,and hormone metabolism.Conclusion:The 55 bio-active components in Horcha-6 regulate inflammation,hormone metabolism,and neurotransmitters and have potential as a therapy to treat migraines.

Preliminary exploration of animal models of congenital choledochal cysts

BACKGROUND Various animal models have been used to explore the pathogenesis of choledochal cysts(CCs),but with little convincing results.Current surgical techniques can achieve satisfactory outcomes for treatment of CCs.Consequently,recent studies have focused more on clinical issues rather than basic research.Therefore,we need appropriate animal models to further basic research.AIM To establish an appropriate animal model that may contribute to the investigation of the pathogenesis of CCs.METHODS Eighty-four specific pathogen-free female Sprague-Dawley rats were randomly allocated to a surgical group,sham surgical group,or control group.A rat model of CC was established by partial ligation of the bile duct.The reliability of the model was confirmed by measurements of serum biochemical indices,morpho-logy of common bile ducts of the rats as well as molecular biology experiments in rat and human tissues.RESULTS Dilation classified as mild(diameter,≥1 mm to<3 mm),moderate(≥3 mm to<10 mm),and severe(≥10 mm)was observed in 17,17,and 2 rats in the surgical group,respectively,while no dilation was observed in the control and sham surgical groups.Serum levels of alanine aminotransferase,aspartate aminotrans-ferase,total bilirubin,direct bilirubin,and total bile acids were significantly elevated in the surgical group as compared to the control group 7 d after surgery,while direct bilirubin,total bilirubin,and gamma-glutamyltransferase were further increased 14 d after surgery.Most of the biochemical indices gradually decreased to normal ranges 28 d after surgery.The protein expression trend of signal transducer and activator of transcription 3 in rat model was consistent with the human CC tissues.CONCLUSION The model of partial ligation of the bile duct of juvenile rats could morphologically simulate the cystic or fusiform CC,which may contribute to investigating the pathogenesis of CC.

Experimental models of high-risk bowel anastomosis in rats:A systematic review

BACKGROUND Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity,that negatively affect the patients’quality of life.Experimental studies play an important role in understanding the pathophysiological background of anastomotic healing and there are still many fields that require further investigation.Knowledge drawn from these studies can lead to interventions or techniques that can reduce the risk of anastomotic leak in patients with high-risk features.Despite the advances in experimental protocols and techniques,designing a high-quality study is still challenging for the investigators as there is a plethora of different models used.AIM To review current state of the art for experimental protocols in high-risk anastomosis in rats.METHODS This systematic review was performed according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.To identify eligible studies,a comprehensive literature search was performed in the electronic databases PubMed(MEDLINE)and Scopus,covering the period from conception until 18 October 2023.RESULTS From our search strategy 102 studies were included and were categorized based on the mechanism used to create a high-risk anastomosis.Methods of assessing anastomotic healing were extracted and were individually appraised.CONCLUSION Anastomotic healing studies have evolved over the last decades,but the findings are yet to be translated into human studies.There is a need for high-quality,well-designed studies that will help to the better understanding of the pathophysiology of anastomotic healing and the effects of various interventions.

MicroRNAs in mouse and rat models of experimental epilepsy and potential therapeutic targets

Epilepsy is a common and serious neurological disease that causes recurrent seizures. The brain damage caused by seizures can lead to depression, anxiety, cognitive impairment, or disability. In almost all cases chronic seizures are difficult to cure. MicroRNAs are widely expressed in the central nervous system and play important roles in the pathogenesis of several neurological disorders, including epilepsy. A variety of animals(mostly mice and rats) have been used to induce experimental epilepsy using different protocols and miRNA profiling performed. Most of the recent studies reviewed had performed miRNA profiling in hippocampal tissues and a large number of microRNAs were dysregulated when compared to controls. Most notably, miR-132-3p,-146a-5p,-10a-5p,-21a-3p,-27a-3p,-142a-5p,-212-3p,-431-5p, and-155 were upregulated in both the mouse and rat studies. Overexpression of miR-137 and miR-219 decreased seizure severity in a mouse epileptic model, and suppression of miR-451,-10a-5p,-21a-5p,-27a-5p,-142a-5p,-431-5p,-155, and-134 had a positive influence on seizure behavior. In the rat studies, overexpression of miR-139-5p decreased neuronal damage in drug-resistant rats and inhibition of miR-129-2-3p,-27a-3p,-155,-134,-181a, and-146a had a positive effect on seizure behavior and/or reduced the loss of neuronal cells. Further studies are warranted using adult female and immature male and female animals. It would also be helpful to test the ability of specific agomirs and antagomirs to control seizure activity in a subhuman primate model of epilepsy such as adult marmosets injected intraperitoneally with pilocarpine or cynomolgus monkeys given intrahippocampal injections of kainic acid.

Mechanism of AiTongXiao granule in the treatment of hepatocellular carcinoma based on network pharmacology and rat transplanted liver cancer model

Objective:To investigate the mechanism of action and material basis of AiTongXiao granule in the treatment of hepatocellular carcinoma(HCC)based on network pharmacology and transplanted liver cancer rat model.Methods:TCMSP database was used to screen out effective components and its corresponding potential pharmaceutical targets,and databases including Gene Cards,OMIM,Drugbank and TTD were further used to collect HCC-related drug targets.The intersecting targets were obtained by mapping the drug and disease targets.The component-targets network was constructed and visualized by Cytoscape 3.8.2 software.Protein-protein interaction(PPI)network was built by STRING online platform,and the topological relationship and core targets was analyzed and screened by using CytoNCA software.In addition,Metascape database was used to perform gene ontology(GO)enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis of the core targets.At last,rat liver transplanted liver cancer model was established by using Walker-256 cell line and treated by AiTongXiao granule for 15 days.Western blot was used to further compare the expression levels of AKT,pAKT,p53,p-p53,ERK1/2 and ERK1/2 in the tumor between treatment group and the control group.Results:257 active components were obtained from AiTongXiao granule,corresponding to 294 drug targets.Meanwhile,233 of the 7993 HCC disease targets were screened out between AiTongXiao granule drug and HCC disease targets.11 core targets including AKT1,IL6,TP53,MAPK3,TNF,JUN,CASP3,MAPK1,MYC,PTGS2,MMP9 were further obtained by median screening.GO and KEGG analysis results showed that these core targets enriched to HBV,TNF and cancer related pathways.The rat transplanted liver cancer model results indicated significant down regulation for AKT,p-AKT,pERK1/2,and significant up regulation of p-p53 after AiTongXiao granule treatment(P<0.05).Conclusion:AiTongXiao granule could act to multiple cancer related pathways,and AKT,p53 and ERK1/2 were validated to be regulated by ATXF in rat model.The mechanism may be through the regulation of the above signaling pathways to exert anti-liver cancer effect.

Motivational and Methodological Factors Involved in the Helping Behavior Test in Laboratory Rodents

Empathy allows humans and other animals to share the emotional state of another, adopting that individual’s perspective on a given situation. This ability is fundamental for species living in groups. Helping behavior in laboratory animals has been used to study empathy. In this test, subjects are exposed to a conspecific that is trapped and learn to open the cage to release the other animal. However, the interpretation of helping behavior as an emphatically motivated action is still controversial. Here we review the studies that use the helping behavioral test proposed by Ben-Ami Bartal and colleagues in 2011 to better understand motivational factors for this behavior. In addition, we compare methodological aspects of these studies. In conclusion, helping behavior can be driven by empathy, but other factors such as the desire for social contact and learning components cannot be ruled out as motivators. In addition, studies focused on evaluating neurobiological mechanisms underlying helping behavior in laboratory rodents can help elucidate the factors involved in releasing the trapped co-specific.

Protective effect of liraglutide on the myocardium of type 2 diabetic rats by inhibiting polyadenosine diphosphate-ribose polymerase-1

BACKGROUND In recent years,studies have found that the occurrence and development of diabetic cardiomyopathy(DCM)is closely related to an increase in polyadenosine diphosphate-ribose polymerase-1(PARP-1)activity.PARP-1 activation could be involved in the pathophysiological process of DCM by promoting oxidative stress,the inflammatory response,apoptosis and myocardial fibrosis.AIM To investigate the mechanism of liraglutide in improving myocardial injury in type 2 diabetic rats,further clarified the protective effect of liraglutide on the heart,and provided a new option for the treatment of DCM.METHODS Forty healthy male SD rats aged 6 wk were randomly divided into two groups,a normal control group(n=10)and a model group(n=30),which were fed an ordinary diet and a high-sugar and high-fat diet,respectively.After successful modeling,the rats in the model group were fed a high-glucose and high-fat diet for 4 wk and randomly divided into a model group and an intervention group(further divided into a high-dose group and a low-dose group).The rats were fed a high-glucose and high-fat diet for 8 wk and then started drug intervention.Blood samples were collected from the abdominal aorta to detect fasting blood glucose and lipid profiles.Intact heart tissue was dissected,and its weight was used to calculate the heart weight index.Haematoxylin and eosin staining was used to observe the pathological changes in the myocardium and the expression of PARP-1 in the heart by immunohistochemistry.RESULTS The body weight and heart weight index of rats in the model group were significantly increased compared with those in the normal control group,and those in the intervention group were decreased compared with those in the model group,with a more obvious decrease observed in the high-dose group(P<0.05).In the model group,myocardial fibers were disordered,and inflammatory cells and interstitial fibrosis were observed.The cardiomyopathy of rats in the intervention group was improved to different degrees,the myocardial fibers were arranged neatly,and the myocardial cells were clearly striated;the improvement was more obvious in the high-dose group.Compared with the normal control group,the expression of PARP-1 in myocardial tissue of the model group was increased,and the difference was statistically significant(P<0.05).After liraglutide intervention,compared with the model group,the expression of PARP-1 in myocardial tissue was decreased,and the reduction was more obvious in the high-dose group(P<0.05)but still higher than that in the normal control group.CONCLUSION Liraglutide may improve myocardial injury in type 2 diabetic rats by inhibiting the expression of myocardial PARP-1 in a dose-dependent manner.

Establishment of extensively drug-resistant Pseudomonas aeruginosa pneumonia model in rat

Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.

A comparative study of two methods for establishing a chronic non‑bacterial prostatitis model in rats‑

Objective:To compare the biological characteristics and stability of the chronic non-bacterial prostatitis(CNP)model in rats induced by the depot combined with estrogen induction method and the autoimmune response induction method.Methods:The CNP rat model was prepared using the depot combined with 17β-estradiol induction method in the depot hormone group and three concentrations of prostate protein homogenate at 40 mg/mL,20 mg/mL and 10 mg/mL in the autoimmune group,respectively.The degree of prostate tissue damage was evaluated by pathology(HE staining),and the immunoturbidimetric method was used to evaluate the contents of immunoglobulins IgA,IgM and IgG.ELISA was used to evaluate interleukin-1β(IL-1β),interleukin-10(IL-10),tumor necrosis factor-α(TNF-α)and high-sensitivity-C-reactive protein(hs-CRP),and electrochemiluminescence was used to evaluate the expression level of testosterone(T),and the two model methods were compared.Results:Compared with the sham-operated group,the body mass of rats in both models was significantly lower in the depot hormone group and autoimmune group before extraction(P<0.01,P<0.01),and histopathology of the prostate in both models showed destruction of glandular structure and a significant increase in inflammatory cells.Compared with the depot hormone group and the autoimmune group,the histopathological changes and inflammatory pathological scores of prostate and the contents of immune indexes IgA,IgM and IgG were significantly different in the depot hormone group(P<0.05,P<0.05,P<0.05),and the levels of IL-1β,IL-10,TNF-α,hs-CRP and T were significantly changed in the autoimmune group(P<0.01).The comparison between the high,medium and low dose groups of the autoimmune group,in which the pathological changes in the medium dose of the autoimmune group were slightly better than the other two groups between the groups,but the changes in IL-1β,IL-10,TNF-α,hs-CRP,and T in the low dose of the autoimmune group were the most significant(P<0.05).Conclusion:The pathological tissues of the chronic non-bacterial prostatitis model established by the depot combined with estrogen induction method and the autoimmune response induction method both showed significant changes,and the comprehensive indexes indicated that the depot combined with estrogen induction method was a more appropriate modeling choice.

Melatonin ameliorates microvessel abnormalities in the cerebral cortex and hippocampus in a rat model of Alzheimer’s disease

Melatonin can attenuate cardiac microvascular ischemia/reperfusion injury,but it remains unclear whether melatonin can also ameliorate cerebral microvascular abnormalities.Rat models of Alzheimer’s disease were established by six intracerebroventricular injections of amyloidbeta 1–42,administered once every other day.Melatonin(30 mg/kg)was intraperitoneally administered for 13 successive days,with the first dose given 24 hours prior to the first administration of amyloid-beta 1–42.Melatonin ameliorated learning and memory impairments in the Morris water maze test,improved the morphology of microvessels in the cerebral cortex and hippocampus,increased microvessel density,alleviated pathological injuries of cerebral neurons,and decreased the expression of vascular endothelial growth factor and vascular endothelial growth factor receptors 1 and 2.These findings suggest that melatonin can improve microvessel abnormalities in the cerebral cortex and hippocampus by lowering the expression of vascular endothelial growth factor and its receptors,thereby improving the cognitive function of patients with Alzheimer’s disease.This study was approved by the Animal Care and Use Committee of Jinzhou Medical University,China(approval No.2019015)on December 6,2018.

Use of surgical techniques in the rat pancreas transplantation model

BACKGROUND: Pancreas transplantation is currently considered to be the most reliable and effective treatment for insulin-dependent diabetes mellitus (also called type I diabetes). With the improvement of microsurgical techniques, pancreas transplantation in rats has been the major model for physiological and immunological experimental studies in the past 20 years. We investigated the surgical techniques of pancreas transplantation in rats by analysing the difference between cervical segmental pancreas transplantation and abdominal pancreaticoduodenal transplantation. METHODS: Two hundred and forty male adult Wistar rats weighing 200-300 g were used, 120 as donors and 120 as recipients. Sixty cervical segmental pancreas transplants and 60 abdominal pancreaticoduodenal transplants were carried out and vessel anastomoses were made with microsurgical techniques. RESULTS: The time of donor pancreas harvesting in the cervical and abdominal groups was 31 6 and 37.6 +/- 3.8 min, respectively, and the lengths of recipient operations were 49.2 +/- 5.6 and 60.6 +/- 7.8 min. The time for donor operation was not significantly different (P > 0.05), but the recipient operation time in the abdominal group was longer than that in the cervical group (P < 0.05). In isograft transplantation without any preconditioning, I-week survival rates were 93.6% and 86.2% in the cervical and abdominal groups, respectively, and were not significantly different (P > 0.05). CONCLUSIONS: Both pancreas transplantation methods are stable models for immunological and physiological studies in pancreas transplantation. Since each has its own advantages and disadvantages, the designer can choose the appropriate method according to the requirements of the study.

Anti-Obesity, Anti-Atherosclerotic and Anti-Oxidant Effects of Pu-Erh Tea on a High Fat Diet-Induced Obese Rat Model

Pu-erh tea, a traditional Chinese beverage, has been believed to have many benefits to human health and without side effects. In this study, we systematically analyzed the main active components of Pu-erh tea and investigated its anti-obesity, anti-atherosclerotic and anti-oxidant effects using an obese rat model. Obesity was induced by feeding a high-fat diet and subsequently the experimental obese mice were fed with high-fat diet supplemented with low (2.5%), medium (5%) or high (7.5%) doses of Pu-erh tea powder for 6 weeks respectively. As result, the body weight gain of the rats was decreased by medium and high doses of Pu-erh tea treatments. Furthermore, the levels of serum total cholesterol (TC), triglyceride (TG) and atherosclerosis index (AI) were significantly lowered by Pu-erh tea compared to the control group. Conversely, high density lipoproteincholesterol (HDL-C) level of the rats was significantly elevated by Pu-erh tea treatments. In addition, Pu-erh tea treatments increased the activities of anti-oxidative enzymes such as superoxide dismutase (SOD) and glutathione peroxides (GSH-Px), whereas reduced the level of lipid peroxidation product malondialdehyde (MDA) in obese rats. Collectively, our find-ings revealed that Pu-erh tea exerts comprehensive benefits in anti-obesity, anti-atherosclerotic and anti-oxidant effects, therefore can be used as a promising functional food in obesity management.

Therapeutic potential of dental pulp stem cell transplantation in a rat model of Alzheimer’s disease

Dental pulp stem cells are dental pulp-derived mesenchymal stem cells that originate from the neural crest.They exhibit greater potential for the treatment of nervous system diseases than other types of stem cells because of their neurogenic differentiation capability and their ability to secrete multiple neurotrophic factors.Few studies have reported Alzheimer’s disease treatment using dental pulp stem cells.Rat models of Alzheimer’s disease were established by injecting amyloid-β1–42 into the hippocampus.Fourteen days later,5×106 dental pulp stem cells were injected into the hippocampus.Immunohistochemistry and western blot assays showed that dental pulp stem cell transplantation increased the expression of neuron-related doublecortin,NeuN,and neurofilament 200 in the hippocampus,while the expression of amyloid-βwas decreased.Moreover,cognitive and behavioral abilities were improved.These findings indicate that dental pulp stem cell transplantation in rats can improve cognitive function by regulating the secretion of neuron-related proteins,which indicates a potential therapeutic effect for Alzheimer’s disease.This study was approved by the Animal Ethics Committee of Harbin Medical University,China(approval No.KY2017-132)on February 21,2017.

Development of a novel rat model of heterogeneous hepatic injury by injection with colchicine via the splenic vein

AIM To develop a novel rat model of heterogeneous hepatic injury.METHODS Seventy male Sprague-Dawley rats were randomly divided into a control group(n = 10) and a colchicine group(n =60). A 0.25% colchicine solution(0.4 mL/kg) was injected via the splenic vein in the colchicine group to develop a rat model of heterogeneous hepatic injury. An equal volume of normal saline was injected via the splenic vein in the control group. At days 3, 7, and 14 and weeks 4, 8, and 12 after the operation, at least seven rats of the colchicine group were selected randomly for magnetic resonance imaging(MRI) examinations, and then they were euthanized. Ten rats of the control group underwent MRI examinations at the same time points, and then were euthanized at week 12. T2-weighted images(T2 WI) and diffusion weighted imaging(DWI) were used to evaluate the heterogeneous hepatic injury. The heterogeneous injury between the left and right hepatic lobes was assessed on liver sections according to the histological scoring criteria, and correlated with the results of MRI study. RESULTS Obvious pathological changes occurred in the hepatic parenchyma in the colchicine group. Hepatic injury scores were significantly different between the left and right lobes at each time point(P < 0.05). There was a significant difference in apparent diffusion coefficient(ADC) of DWI and liver-to-muscle ratio(LMR) of T2 WI between the left and right lobes of rats in the colchicine group(P < 0.05) at each time point, and similar results were observed between the colchicine and control groups. Besides, there was a significant correlation between hepatic injury scores and ADC values or LMR(r =-0.682, P = 0.000; r =-0.245, P = 0.018).CONCLUSION Injection with colchicine via the splenic vein can be used to successfully develop a rat model of heterogeneous hepatic injury. DWI and T2 WI may help evaluate the heterogeneous injury among liver lobes.

The effect of root of rhododendron on the activation of NF-κB in a chronic glomerulonephritis rat model

Objective： We have explored the role of nuclear factor kappa B（NF-κB） in the pathogenesis of chronic glomemlonephritis, and investigated the effect of rhododendron root on the activation of NF-κB. Methods： Thirty-six Wistar rats were randomly divided into three groups： a control group, a glomerulonephritis model group and a therapy group（glomerulonephritis animals treated with the root of rhododendron）. Bovine serum albumin（BSA） nephritis was induced by subcutaneous immunization and daily intraperitoneal administration of BSA. Twenty-four-hour urinary protein and serum creatinine values were measured, and renal pathology was assessed histologically by optical microscopy and electron microscopy. NF-κB activity was determined by an electrophoretic mobility shift assay（EMSA）. Results：Compared with the control rats, glomerulonephritis model rats exhibited a significant increase in both 24 h urinary protein and serum creatinine, and had abnormal renal histology. The administration of the root of rhododendron ameliorated these changes. NF-κB activity in glomerulonephritis model group was greater than that in rhododendron-treated group, and NF-κB activity was greater in both glomerulonephritis groups than in the control group（P 〈 0.01）. Conclusion：These observations suggest that NF-κB plays a role in the pathogenesis of chronic glomemlonephritis, and rhododendron root may attenuate renal damages by downregulating the activation of NF- κB in this model.

Expression of hypoxia inducible factor-1 alpha and ischemic erythropoietin tolerance in the brain of cerebral ischemic tolerance model rats

BACKGROUND： Hypoxia inducible factor-1 alpha （HIF-1 （x） and erythropoietin（EPO）, possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tolerance （IT）. OBJECTIVE：To observe the neuroprotective effect of cerebral ischemic preconditioning（IPC） of rats, and the expression and mechanism of HIF-1α and target gene erythropoietin in the brain tissue following the formation of cerebral IT. DESIGN ： A randomized and controlled observation SETTING： Department of Neurology, the Affiliated Hospital of Medical College, Qingdao University MATERIALS： Totally 84 enrolled adult healthy male Wistar rats of clean grade, weighing 250 to 300 g, were provided by the Animal Experimental Department, Tongji Medical College of Huazhong University of Science and Technology. Ready-to-use SABC reagent kit and rabbit anti-rat HIF-1α monoclonal antibody were purchased from Boshide Bioengineering Co.Ltd （Wuhan）; Rabbit anti-rat EPO monoclonal antibody was purchased from Santa Cruz Company （USA）. METHODS： This experiment was carried out in the Department of Anatomy, Medical College, Qingdao University during March 2005 to March 2006. ① The 84 rats were divided into 3 groups by a lot： IPC group （n=40）, sham-operation group （n=40） and control group （n=4）. In the IPC group, middle cerebral artery was occluded for 2 hours respectively on the 1^st, 3^rd, 7^th, 14^th and 21^st days of the reperfusion following 10-minute preischemia was made using a modified middle cerebral artery second suture method from Zea-Longa. The rats were sacrificed 22 hours after reperfusion in the end of middle cerebral artery occlusion （MCAO）. That was to say, after 10-minute preischemia, suture was exited to the extemal carotid artery and embedded subcutaneously. Middle cerebral artery was occluded again to form the second reperfusion at the set time point after reperfusion. Twenty-two hours later, rats were sacrificed; In the sham-operation group,the preischemia was substituted by sham-operation（only common carotid artery and crotch were exposed, and MCAO by suture was omitted）, and the other procedures were the same as those in the IPC group. In the control group, rats were given sham-operation twice at an interval of one day, and they were sacrificed 24 hours after the second sham-operation. ② Brain tissue was taken from the rats in each group. Cerebral infarction area of each layer was measured with TTC staining, and total cerebral infarction volume （The total cerebral infarction area of each layerxinterspace ） was calculated. After brain tissue was stained by haematoxylin-esoin （HE）, the form of nerve cells was observed under an optical microscope, and the expressions of HIF-1α（and EPO protein in the brain tissue were detected with immunohistochemical method. MAIN OUTCOME MEASURES： ①Cerebral infarction volume;②form of nerve cell; ③ the expression of HIF-1α and EPO protein in the brain tissue. RESULTS：Totally 84 rats were enrolled in the experiment. The dead rats were randomly supplied during the experiment, and finally 84 rats entered the stage of result analysis. ① Detection of cerebral infarction volume of rats in each group： Cerebral infarction volume in the IPC group was significantly smaller than that in the sham-operation group on the 1^st, 3^rd and 7^th days after reperfusion respectively [（161.2±6.9） mm^3 vs （219.9±11.2） mm^3, （134.9±9.0） mm^3 vs （218.6±13.0） mm^3, （142.9±13.7） mm^3 vs （221.3±14.2） mm^3, t=-8.924, 10.587,7.947, P〈 0.01]. ② Observation of nerve cell form of brain tissue： HE staining showed that the ischemic degree, range and cerebral edema degree of IPC group were significantly milder than those of sham-operation group. ③ The expressions of HIF-1α and EPO protein in cerebral cortex and hippocampus ： The expression of HIF-1αof IPC group was significantly higher than that of sham-operation group on the 1^st, 3^rd and 7^th days after reperfusion respectively （125.93±3.79 vs 117.65±5.60, 140.63±4.64 vs 119.33±4.26, 131.15±2.74 vs 107.60±3.89, t=2.449, 6.763,9.899,P 〈 0.05-0.01）. The expression of EPO of IPC group was significantly higher than that of sham-operation group on the 3^rd and 7^th days after perfusion respectively （141.68±3.29 vs 126.33±4.51, 138.88±2.59 vs 125.58±6.18,t=5.499,3.970, P〈 0.05）. CONCLUSION ： ①IPC can protect the never cells in rat brain and the best time to onset of cerebral IT induced by IPC is 1 to 7 days after reperfusion. ② Neuroprotective effect of cerebral IT might be related to the expression of HIF-1α and its target gene EPO.

Antibacterial Properties of Nano Silver-containing Orthodontic Cements in the Rat Caries Disease Model

The purpose of this study was to evaluate the antibacterial properties of experimental nano silver-containing cements（NSCs） using rat caries disease model. Nano silver base inorganic antibacterial powder was added to the reinforced glass ionomer cement at three different weight ratios to obtain a series of nano silver-containing cements, then two orthodontic cement products and three NSC samples were implanted into rat caries disease model, and their antibacterial properties were evaluated by the scanning electron microscope（SEM）. Moreover, the rat caries disease model were established by inoculating cariogenic bacteria S mutans into antibiotics treated rat mouths and feeding with cariogenic diet. The tested materials were bonded on the surface of the buccal half crowns of the upper fi rst premolar, and then fi xed under the rats＇ front teeth lingual side to acquire enough retention. The SEM results indicated that the growth of streptococcus mutans was very active in group of Transbond XT. One month later, S mutans scattered on the GC Fuji ORTHO LC surface, and then the number signifi cantly increased and arranged in chains after three months. In groups of NSC2, NSC3 and NSC4, the number of S mutans presented the downward trend and tended to disperse individually with the increase of silver nanoparticle content. We may conclude that the incorporation of silver nanoparticle enhanced GC Fuji ORTHO LC the adhesion restrain and killing effect to S mutans.

Effects of Chuanxiongqin hydrochloride on increasing the fluidity of brain cell membrane and scavenging free radicals in model rats with ischemia/reperfusion injury

BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to high rigidity and low fluidity of cell membrane, and the conditions can be changed by Chuanxiongqin. OBJECTIVE: To observe the effect and mechanism of Chuanxiongqin hydrochloride on the fluidity of brain cell membrane in rat models of ischemia/reperfusion. DESIGN: A completely randomized controlled animal trial. SETTINGS: Institute of Brain Sciences; Department of Physiology, Medical College, Datong University. MATERIALS: Twenty male grade Ⅰ Wistar rats of 170-220 g were randomly divided into model group (n =10) and control group (n =10). Chuanxiongqin hydrochloride (molecular mass was 172.2) was purchased from the National Institute for the Control of Pharmaceutical and Biological Products (batch number: 0817-9803); Spin labelers: 5-doxyl-stearlic acid methylester (5DS), 16-doxyl-stearlic acid methylester (16DS), xanthine, xanthine oxidase (XOD) and 5,5-dimeth-1-pyrroline- N-oxide (DMPO) from Sigma Company; Bruker ESP 300 electron paramagnetic resonance (EPR) spectrometer by Bruker Company (Germany). METHODS: The experiments were carried out in the State Key Laboratory of Natural and Biomimetic Drugs, Peking University from June 2001 to July 2002. In the model group, rats were made into models of cerebral ischemia by 30-minute ligation and 2-hour reperfusion of common carotid arteries; The rats in the control group were not made into models. The order parameter (S) and rotational correlation time (τc) were detected with the ESR spectrometer by means of spin labeling. The greater the S and τc, the smaller the fluidity. Meanwhile, the clearance rate of free radicals was detected with ESR spin trapping. The measurement data were compared using the t test. MAIN OUTCOME MEASURES: The S, τc and clearance rates of O2 · and OH· free radicals were compared between the model group and control group. RESULTS: The S and τc in the model group [0.738 4±0.003 5; (8.472±0.027)×10-10 s/circle] were obviously different from those in the control group [0.683 9±0.008 3; (7.945±0.082)×10-10 s/circle, t =5.731, 5.918, P < 0.05], which suggested that ischemia/reperfusion injury decreased the fluidity of brain cell membrane. After adding Chuanxiongqin hydrochloride, there were no obvious differences between the model group [0.688 5±0.030 5; (7.886±0.341)×10-10 s/circle] and control group (P > 0.05), indicating that Chuanxiongqin hydrochloride could recover the fluidity of brain cell membrane after ischemia/reperfusion injury close to the level in the normal control group. Chuanxiongqin hydrochloride could directly scavenge the O2 · and OH· free radicals, and the maximal clearance rates were 83.92% and 44.99% respectively. CONCLUSION: Chuanxiongqin hydrochloride increases the fluidity of membrane of ischemia-injured brain cell by scavenging both O2 ·and OH· free radicals.

Involvement of CRH Receptors in the Neuroprotective Action of R-Apomorphine in the Striatal 6-OHDA Rat Model

The dopamine D1-D2 receptor agonist, R-apomorphine, has been shown to be neuroprotective in different models of Parkinson’s disease. Different mechanisms of action for this effect have been proposed, but not verified in the striatal 6-hydroxydopamine rat model. In this study, the expression of a set of genes involved in 1) signaling, 2) growth and differentiation, 3) neuronal regeneration and survival, 4) apoptosis and 5) inflammation in the striatum was measured after a subchronic R-apomorphine treatment (10 mg/kg/day, subcutaneously, during 11 days) in the striatal 6-hydroxydopamine rat model. The expression of 84 genes was analysed by using the rat neurotrophins and receptors RT2 ProfilerTM PCR array. The neuroprotective effects of R-apomorphine in the striatal 6-hydroxydopamine model were confirmed by neurochemical and behavioural analysis. The expression data suggest the observed neuroprotection involved the alteration of the gene and the protein expression levels of the anti-inflammatory corticotropin releasing hormone receptor (CRHR) 1 and the pro-inflammatory CRHR2 receptor confirming its potential anti-inflammatory action.

Inflammation and apoptosis accelerate progression to irreversible atrophy in denervated intrinsic muscles of the hand compared with biceps: proteomic analysis of a rat model of obstetric brachial plexus palsy

In treating patients with obstetric brachial plexus palsy,we noticed that denervated intrinsic muscles of the hand become irreversibly atrophic at a faster than denervated biceps.In a rat model of obstetric brachial plexus palsy,denervated intrinsic musculature of the forepaw entered the irreversible atrophy far earlier than denervated biceps.In this study,isobaric tags for relative and absolute quantitation were examined in the intrinsic musculature of forepaw and biceps on denervated and normal sides at 3 and 5 weeks to identify dysregulated proteins.Enrichment of pathways mapped by those proteins was analyzed by Kyoto Encyclopedia of Genes and Genomes analysis.At 3 weeks,119 dysregulated proteins in denervated intrinsic musculature of the forepaw were mapped to nine pathways for muscle regulation,while 67 dysregulated proteins were mapped to three such pathways at 5 weeks.At 3 weeks,27 upregulated proteins were mapped to five pathways involving inflammation and apoptosis,while two upregulated proteins were mapped to one such pathway at 5 weeks.At 3 and 5 weeks,53 proteins from pathways involving regrowth and differentiation were downregulated.At 3 weeks,64 dysregulated proteins in denervated biceps were mapped to five pathways involving muscle regulation,while,five dysregulated proteins were mapped to three such pathways at 5 weeks.One protein mapped to inflammation and apoptotic pathways was upregulated from one pathway at 3 weeks,while three proteins were downregulated from two other pathways at 5 weeks.Four proteins mapped to regrowth and differentiation pathways were upregulated from three pathways at 3 weeks,while two proteins were downregulated in another pathway at 5 weeks.These results implicated inflammation and apoptosis as critical factors aggravating atrophy of denervated intrinsic muscles of the hand during obstetric brachial plexus palsy.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Fudan University,China(approval No.DF-325)in January 2015.