The striatum and globus pallidus are principal nuclei of the basal ganglia. Nissl- and acetylcholinesterase-stained sections of the tree shrew brain showed the neuroanatomical features of the caudate nucleus (Cd), internal capsule (ic), putamen (Pu), accumbens, internal globus pallidus, and external globus pallidus. The ic separated the dorsal striatum into the Cd and Pu in the tree shrew, but not in rats and mice. In addition, computer-based 3D images allowed a better understanding of the position and orientation of these structures. These data provided a large-scale atlas of the striatum and globus pallidus in the coronal, sagittal, and horizontal planes, the first detailed distribution of parvalbumin-immunoreactive cells in the tree shrew, and the differences in morphological characteristics and density of parvalbumin-immunoreactive neurons between tree shrew and rat. Our findings support the tree shrew as a potential model for human striatal disorders.
Acetylcholinesterase ; metabolism ; Animals ; Brain Mapping ; Corpus Striatum ; anatomy & histology ; cytology ; metabolism ; Globus Pallidus ; anatomy & histology ; cytology ; metabolism ; Imaging, Three-Dimensional ; Male ; Mice ; Mice, Inbred C57BL ; Models, Neurological ; Neurons ; metabolism ; Parvalbumins ; metabolism ; Rats ; Rats, Sprague-Dawley ; Statistics, Nonparametric ; Tupaiidae ; anatomy & histology

Diffusion-weighted magnetic resonance imaging (dMRI) is widely used to study white and gray matter (GM) micro-organization and structural connectivity in the brain. Super-resolution track-density imaging (TDI) is an image reconstruction method for dMRI data, which is capable of providing spatial resolution beyond the acquired data, as well as novel and meaningful anatomical contrast that cannot be obtained with conventional reconstruction methods. TDI has been used to reveal anatomical features in human and animal brains. In this study, we used short track TDI (stTDI), a variation of TDI with enhanced contrast for GM structures, to reconstruct direction-encoded color maps of fixed tree shrew brain. The results were compared with those obtained with the traditional diffusion tensor imaging (DTI) method. We demonstrated that fine microstructures in the tree shrew brain, such as Baillarger bands in the primary visual cortex and the longitudinal component of the mossy fibers within the hippocampal CA3 subfield, were observable with stTDI, but not with DTI reconstructions from the same dMRI data. The possible mechanisms underlying the enhanced GM contrast are discussed.
Animals ; Brain Mapping ; Diffusion Tensor Imaging ; methods ; Hippocampus ; diagnostic imaging ; Image Processing, Computer-Assisted ; methods ; Male ; Neural Pathways ; diagnostic imaging ; Tupaiidae ; anatomy & histology ; Visual Cortex ; diagnostic imaging

Chronic hepatitis B affects 400 million people worldwide and is one of the leading causes of liver-related morbidity and mortality. All clinically available hepatitis B virus (HBV) drugs are nucleoside or nucleotide analogs that inhibit viral reverse transcriptase (RT) activity. Resistance to these HBV drugs has been widely reported, and is due to specific mutations in the viral RT domain. Therefore, the development of new, non-polymerase targeting anti-HBV agents is urgently needed. A potential drug target, the HBV receptor that mediates the viral entry process, has been recently identified using human primary hepatocytes, northern tree shrew (Tupaia belangeri) hepatocytes, and HepaRG cells. A transporter of bile acids, sodium taurocholate cotransporting polypeptide (NTCP), was identified as the receptor for HBV and hepatitis D virus, and the transport function of NTCP was correlated with HBV entry. Therefore, functional inhibitors of NTCP may inhibit HBV infection, and viral entry was blocked by several NTCP receptor-targeting compounds. The HBV receptor is an attractive target for development of entry inhibitors, and serves as a model for the mechanistic study of HBV entry and infection. This review will summarize the characteristics and clinical importance of NTCP, and will discuss the potential therapeutic use of NTCP inhibitors to prevent HBV entry.
Bile Acids and Salts ; Hepatitis B virus ; Hepatitis B* ; Hepatitis B, Chronic ; Hepatitis Delta Virus ; Hepatocytes ; Humans ; Mortality ; RNA-Directed DNA Polymerase ; Taurocholic Acid ; Tupaiidae

Animals ; Behavior, Animal ; Reproduction ; physiology ; Social Behavior ; Tupaiidae ; physiology

Metabolomics represents an emerging and powerful discipline that provides an accurate and dynamic picture of the phenotype of bio-systems through the study of potential metabolites that could be used as therapeutic targets and for the discovery of new drugs. Hepatitis C virus (HCV) is a leading cause of liver disease worldwide, and is a major burden on public health. It is hypothesized that an animal model of HCV infection would produce unique patterns of endogenous metabolites. Herein, a method for the construction of efficient networks is presented with regard to the proteins of bear bile powder (PBBP) that protect against HCV as a case study. Ultra-performance liquid chromatography, coupled with electrospray ionization/quadrupole-time-of-flight high definition mass spectrometry (UPLC-HDMS), coupled with pattern recognition methods and computational systems analysis were integrated to obtain comprehensive metabolomic profiling and pathways of the large biological data sets. Among the regulated pathways, 38 biomarkers were identified and two unique metabolic pathways were indicated to be differentially affected in HCV animals. The results provided a systematic view of the development and progression of HCV, and also could be used to analyze the therapeutic effects of PBBP, a widely used anti-HCV medicine. The results also showed that PBBP could provide satisfactory effects on HCV infection through partially regulating the perturbed pathway. The most promising use in the near future would be to clarify the pathways for the drugs and obtain biomarkers for these pathways to help guide testable predictions, provide insights into drug action mechanisms, and enable an increase in research productivity toward metabolomic drug discovery.
Animals ; Antiviral Agents ; chemistry ; metabolism ; pharmacology ; Bile ; chemistry ; metabolism ; Hepacivirus ; drug effects ; physiology ; Hepatitis C ; drug therapy ; virology ; Humans ; Male ; Metabolomics ; Proteins ; chemistry ; metabolism ; pharmacology ; Proteomics ; Spectrometry, Mass, Electrospray Ionization ; Tupaiidae ; Ursidae

OBJECTIVETo evaluate the utility of the cross-species screening strategy for investigating key molecule(s) involved in onset and progression of hepatocellular carcinoma (HCC).

METHODSHCC-related molecule data from our previous studies and in the literature were collected to establish a cross-species dataset. Tissue samples of HCC, non-HCC surrounding liver (para-HCC), and normal liver that were collected from humans, tree shrews and rats. The genes reported to have the most differential expression in HCC were verified by analyzing the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively.

RESULTSThe cross-species dataset of HCC-related molecules included four genes: epidermal fatty acid-binding protein (E-FABP), liver (L)-FABP, tyrosine a-ketoglutarate transaminase (TKT), and cytokeratin (CK8). In humans, E-FABP mRNA expression was significantly higher (P less than 0.05) in HCC (0.87+/-0.14 vs. para-HCC: 0.64+/-0.12 and normal liver: 0.67+/-0.07; F=20.910). Similar results were obtained in tree shrew (HCC: 0.87 +/- 0.25 vs. para-HCC: 0.73 +/- 0.19 and normal liver: 0.68+/-0.19; F=3.807) and rat (HCC: 0.97+/-0.22 vs. para-HCC: 0.78+/-0.16 and normal liver: 0.80 +/- 0.13; F=4.482). The Western blotting analyses revealed a similar statistically significant trend.

CONCLUSIONThe cross-species screening strategy for tumor genes may represent a feasible and convenient process of identifying key molecule(s) for human HCC. E-FABP may be a particularly crucial molecule for hepatocarcinogenesis.

Adult ; Aged ; Animals ; Carcinoma, Hepatocellular ; metabolism ; Case-Control Studies ; Epidermis ; chemistry ; Fatty Acid-Binding Proteins ; metabolism ; Female ; Humans ; Liver ; metabolism ; Liver Neoplasms ; metabolism ; Male ; Middle Aged ; Rats ; Tupaiidae ; metabolism

The aim of this study is to establish a method to culture and purify cerebral astrocyte of tree shrew (Tupaia belangeri), a kind of new laboratorial animal which is a relative of primates. Newborn tree shrews were used in this experiment. The cortex of cerebrum was isolated and placed in 4°C for 20 min to injure neurons. The cortical tissue was disaggregated by trypsin digestion. Differential attachment method was used to remove fibroblasts. The mixed culture was rinsed by trypsin (0.005%) solution to remove neurons. Upon reaching 70% confluence, the culture was subjected to static trypsin digestion until a white slice film exfoliated from the bottom of culture bottle. This film, i.e. astrocyte layer, was taken out and cultured, and the third passage was identified by immunocytochemical staining and immunofluorescence with anti-glial fibrillary acidic protein (GFAP) antibody. The result showed the purity of tree shrew astrocytes was more than 98%. Thus the method to culture highly purified astrocyte of tree shrew was successfully established, which would contribute to further study in central nervous system physiology and diseases in this new laboratorial animal.
Animals ; Astrocytes ; cytology ; Brain ; cytology ; Cell Separation ; methods ; Primary Cell Culture ; methods ; Tupaiidae

OBJECTIVETo observe the hepatitis B virus (HBV) replication in the tree shrews that were inoculated with HBV at neonatal period.

METHODSSix new-born tree shrews were inoculated with human HBV positive serum. Blood samples and liver biopsies were collected at different time points after inoculation. The HBV infection markers were tested by nested polymerase chain reaction (nPCR), fluorescence quantitative polymerase chain reaction (FQ-PCR), Southern blot, ELISA and immunohistochemistry staining. The liver tissues were observed under electron and light microscope.

RESULTS48 weeks after inoculation, HBV DNA and HBV cccDNA were detected in the serum and liver samples of three animals (number 1, 2 and 6) by nPCR. The copy-numbers of HBV DNA detected by FQ-PCR in their serum and liver samples were 103 and-104/ml respectively,and the total DNA in 1microg liver tissue was 107-108. Southern blot indicated that HBV replication intermediates such as HBV cccDNA and HBV ssDNA was detectable in liver tissues. HBsAg was detected by ELISA, and immunohistochemical staining showed a gradual increase of HBsAg-positive liver cells. High copy number of HBV DNA and suspected HBV EM particles could be detected in the liver samples from one of the three animals that have survived more than 2 years after inoculation. The other three animals showed low HBV DNA copy number, and the rest of the signs of HBV infection were negative or transiently positive.

CONCLUSIONSNeonatal tree shrews can be infected with human HBV. HBV can replicate inside the liver cells of tree shrew.

Animals ; Animals, Newborn ; Biopsy ; DNA, Circular ; analysis ; blood ; DNA, Viral ; analysis ; blood ; Disease Models, Animal ; Hepatitis B ; etiology ; pathology ; virology ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; genetics ; physiology ; Humans ; Immunohistochemistry ; Liver ; pathology ; virology ; Polymerase Chain Reaction ; methods ; Tupaiidae ; Virus Replication

OBJECTIVETo evaluate the mRNA and protein expressions of peroxiredoxin II (PrxII) in hepatocellular carcinoma (HCC) and their significance.

METHODSHCC was induced by aflatoxin B1 (AFB1) in 6 tree shrews (Tupaia belangeri chinensis). The expression levels of PrxII mRNA and protein were detected by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot on HCC tissues and on their surrounding liver tissues (para-HCC). Biopsied liver tissues were taken before the HCC induction (pre-HCC) from the same animals and from a group of blank controlled animals that served as controls. Liver biopsy specimens from 18 cases of human HCC and from 17 healthy human volunteers were studied using the same methods.

RESULTSThe mRNA and protein expressions of PrxII in tree shrew HCC tissues were significantly higher than those in para-HCC and pre-HCC tissues, and also higher than those in the liver tissues from the control animals (all P < 0.05). The expression levels of PrxII mRNA and protein in human HCC tissues were also significantly higher than those in their para-HCC tissues and in the human normal liver tissues (P < 0.05).

CONCLUSIONPrxII might play an important role in hepatocarcinogenesis and might be used as a molecular target for HCC prevention and treatment.

Adult ; Aged ; Animals ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Female ; Humans ; Liver ; metabolism ; pathology ; Liver Neoplasms ; metabolism ; pathology ; Liver Neoplasms, Experimental ; metabolism ; pathology ; Male ; Middle Aged ; Peroxiredoxins ; genetics ; Tupaiidae

BACKGROUNDIt has been known that platelet activating factor receptors (PAFR) may mediate many acute pathological responses and that PAFR antagonist Ginkgolide B (GB) possesses multiple effects, but the actions of GB on PAFR affinity and mitochondrial respiration in the ischemic neuron were unclear until now. This study explored the possible effects of GB on PAFR and the mitochondrial respiration of the neuron in the ischemic microenvironment.

METHODSThrombotic cerebral ischemia in tree shrews was induced by a photochemical reaction; changes in the regional cerebral blood flow (rCBF, using (99m)Tc tracer technique), the brain water content (specific gravimetric method), PAFR (3H-labelled PAF assay), the respiratory control rate (RCR), the phosphorus-oxygen (P/O) ratio of mitochondrial respiration (Clark oxygen electrode), mitochondrial permeability transition (MPT) pore, and the mitochondrial ultrastructure in the ischemic neurons were also observed. Data were compared between the two groups (the ischemia group vs the sham group, and the ischemia group vs the GB group).

RESULTSThere were high affinity and low affinity sites for PAFR on the tree threws' brain cell membranes. The varying-affinity PAFR binding sites, the respiration state III, the state IV, RCR, the P/O ratio of the mitochondria, and the rCBF all decreased markedly (respectively, P < 0.01 and P < 0.05), but the water content increased (P < 0.01) in the ischemia group after the application of cerebral thrombosis. In tree shrews treated with GB (5 mg/kg i.v.) 6 hours after photochemical reaction, their PAFR binding sites and respiratory state increased markedly. The rCBF gradually increased and the brain edema ameliorated (P < 0.01) at 24h after cerebral ischemia. There were significant differences between the ischemia group and sham group (P < 0.01). In GB treated isolated neurons' mitochondria, with or without cerebral ischemia, the energy metabolism of the mitochondria had not been changed.

CONCLUSIONSThe activation of the PAFR may play an important role in the inhibition of the mitochondrial respiration and the induction of neuronal damage after cerebral thrombosis; however, GB possesses neuroprotective effects by improving mitochondrial metabolism.

Animals ; Brain Ischemia ; drug therapy ; metabolism ; pathology ; Female ; Ginkgolides ; therapeutic use ; Lactones ; therapeutic use ; Male ; Mitochondria ; drug effects ; metabolism ; Neuroprotective Agents ; therapeutic use ; Oxygen Consumption ; drug effects ; Platelet Activating Factor ; antagonists & inhibitors ; Platelet Membrane Glycoproteins ; analysis ; Receptors, G-Protein-Coupled ; analysis ; Tupaiidae