RNA sequencing and proteomic profiling reveal alterations by MPTP in chronic stomach mucosal injury in tree shrew Chinese (Tupaia belangeri chinensis).

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that can cause gastrointestinal ulcers by affecting dopamine levels. Therefore, MPTP has been considered a toxic substance that causes gastric ulcer disease in experimental animals. In this study, tree shrews were used as the animal model of gastric mucosa injury, and MPTP was intraperitoneally injected at a lower MPTP dosage 2 mg/kg/day for 13 weeks, while tree shrews were not injected as the control group. Under the light microscope, local congestion or diffuse bleeding points of gastric mucosa and multiple redness and swelling bleeding symptoms on the inner wall were observed in the treatment group, as well as immune cell infiltration was found in HE staining, but no such phenomenon was observed in the control group. In order to explore the molecular basis of changes in MPTP induced gastric mucosa injury, the transcriptome and proteome data of gastric mucosa were analyzed. We observed significant differences in mRNA and protein expression levels under the influence of MPTP. The changes in mRNA and proteins are related to increased immune infiltration, cellular processes and angiogenesis. More differentially expressed genes play a role in immune function, especially the candidate genes RPL4 and ANXA1 with significant signal and core role. There are also differentially expressed genes that play a role in mucosal injury and shedding, especially candidate genes GAST and DDC with certain signaling and corresponding functions. Understanding the factors and molecular basis that affect the expression of related genes is crucial for coping with Emotionality gastric mucosa injury disease and developing new treatment methods to establish the ability to resist disease.

Inosine induces acute hyperuricaemia in rhesus monkey (Macaca mulatta) as a potential disease animal model.

CONTEXT: The uric acid metabolism pathway is more similar in primates and humans than in rodents. However, there are no reports of using primates to establish animal models of hyperuricaemia (HUA). OBJECTIVES: To establish an animal model highly related to HUA in humans. MATERIALS AND METHODS: Inosine (75, 100 and 200 mg/kg) was intraperitoneally administered to adult male rhesus monkeys (n = 5/group). Blood samples were collected over 8 h, and serum uric acid (SUA) level was determined using commercial assay kits. XO and PNP expression in the liver and URAT1, OAT4 and ABCG2 expression in the kidneys were examined by qPCR and Western blotting to assess the effects of inosine on purine and uric acid metabolism. The validity of the acute HUA model was assessed using ulodesine, allopurinol and febuxostat. RESULTS: Inosine (200 mg/kg) effectively increased the SUA level in rhesus monkeys from 51.77 ± 14.48 at 0 h to 178.32 ± 14.47 µmol/L within 30 min and to peak levels (201.41 ± 42.73 µmol/L) at 1 h. PNP mRNA level was increased, whereas XO mRNA and protein levels in the liver were decreased by the inosine group compared with those in the control group. No changes in mRNA and protein levels of the renal uric acid transporter were observed. Ulodesine, allopurinol and febuxostat eliminated the inosine-induced elevation in SUA in tested monkeys. CONCLUSIONS: An acute HUA animal model with high reproducibility was induced; it can be applied to evaluate new anti-HUA drugs in vivo and explore the disease pathogenesis.

Alpha-synuclein is highly prone to distribution in the hippocampus and midbrain in tree shrews, and its fibrils seed Lewy body-like pathology in primary neurons.

The Chinese tree shrew (TS) has many unique advantages that make it suitable for use as an experimental animal model for human disease including moderate body size, low cost of feeding, short reproductive cycle and lifespan, and close phylogenetic relationship to primates. Our previous studies have shown that TS treated with the mitochondrial inhibitor MPTP displayed classic Parkinsonian symptoms. Additionally, the structure of TS alpha-synuclein (α-syn) is highly homologous to that found in humans. Previous studies have concluded that misfolded, fibrillar α-syn is a hallmark of α-synucleinopathies. In this study, we examined the distribution and expression levels of α-syn in different TS brain regions. We also obtained recombinant TS α-syn protein to study its aggregation and cytotoxic properties in primary neurons. Our results showed that α-syn was expressed in numerous different brain regions in TS but was most abundant in the hippocampus and midbrain. The recombinant α-syn of TS displayed straight fibrils when incubated for 72 h in vitro, which is very similar to human α-syn. When exposed to primary neurons, the TS and human α-syn fibrils led to cytotoxicity and Lewy-like pathology. Our findings indicated that TS could be a potential animal model to study the pathology of α-synucleinopathies.

Mixed cryoglobulinaemia in a rhesus macaque (Macaca mulatta).

We report cryoglobulinaemia (CG) in a rhesus macaque whose serum sample was gel-like at <37°C and resolubilised upon warming. Mixed CG was diagnosed using serum protein electrophoresis and serum immunofixation electrophoresis. Renal damage and arthrophyma were observed during necropsy. This is the first report of CG in a non-human primate.

Potassium oxonate induces acute hyperuricemia in the tree shrew (tupaia belangeri chinensis).

Potassium oxonate, a selectively competitive uricase inhibitor, produced hyperuricemia (HUA) in rodents in a previous study. In this study, we employed the tree shrew as an animal model to study potassium oxonate-induced HUA. The effect of allopurinol (ALLO), a uric acid reducer, was also examined in this model. Potassium oxonate at doses of 5, 20, 40, 60, 80, 100, and 1,000 mg/kg was given intraperitoneally to tree shrews. The results showed that potassium oxonate can effectively increase the levels of uric acid in tree shrews at doses ranging from 40 to 100 mg/kg. Semiquantitative RT-PCR showed that the xanthine dehydrogenase/oxidase (XDH/XO) mRNA expression level was significantly higher in the liver tissue of tree shrews with high levels of uric acid. There were no changes in serum urea nitrogen, or serum creatinine values. ALLO can significantly decrease serum uric acid levels (P<0.01) and raise XDH/XO mRNA expression levels in the liver tissue of tree shrews with HUA. XDH/XO mRNA expression levels did not change in untreated tree shrews. Studies on acute toxicity in the tree shrew did not show any significantly abnormal signs. There were no adverse effects at the macroscopic level up to doses ≤100 mg/kg. Potassium oxonate induced acute HUA in tree shrews at lower doses compared with other animal models. Potassium oxonate-treated tree shrews may be a potential animal model for studying pathogenic mechanism and evaluating a new therapeutic agent for treatment of HUA in humans.

Dopaminergic neuron-like cells derived from bone marrow mesenchymal stem cells by Lmx1α and neurturin overexpression for autologous cytotherapy in hemiparkinsonian rhesus monkeys.

Bone marrow-derived mesenchymal stem cells hold great potential for cytotherapeutics of neurodegenerative disorders, including Parkinson's disease. The neurotrophic factor neurturin can rescue dopaminergic neurons damaged during the disease process. Lmx1α can promote mesencephalic dopaminergic differentiation during embryogenesis. In this study, we tested a cytotherapeutic strategy combining NTN/Lmx1α gene therapy and cell transplantation to ameliorate disease progression in hemiparkinsonian rhesus. Rhesus BMSCs were prepared for autologous grafting by transfection with recombinant adenoviral vectors expressing secreted NTN and Lmx1α,and cultured in the presence of induce factors, particularly the Lmx1α regulatory factor sonic hedgehog, to guide dopaminergic differentiation. These induced rh-BMSCs exhibited gene/protein expression phenotypes resembling nigral dopaminergic neurons. They survived and retained dopaminergic function following stereotaxic injection into the MPTP-lesioned right-side substantia nigra as indicated by SPECT measurement of DAT activity. Injected cells preserved and supplemented the remaining endogenous population of dopamine neurons (TH-positive cell ipsilateral/contralateral ratio was 56.81% ± 7.28% vs. 3.86%±1.22% in vehicle-injected controls; p<0.05). Cell injection also partially restored motor function and reduce apomorphine-evoked rotation (p<0.05). Moreover, function recovery occurred earlier than in previous studies on injected BMSCs. Our findings demonstrate a promising strategy for restoration of PD-associated motor dysfunction by transplantation of autologous BMSCs overexpressing NTN/Lmx1α.

[Evaluation of immune responses and related patho-inflammatory reactions of a candidate inactivated EV71 vaccine in neonatal monkeys].

OBJECTIVE: To evaluate the safety of enterovirus type 71 (EV71) inactivated vaccine (human diploid derived) for infection prevention in an animal model by investigating the immune responses and related patho-inflammatory reactions. METHODS: In the neonatal monkey model for EV71 vaccine protection, vaccinated group (n = 4) and unvaccinated group (n = 4) were attacked with live virus at the same time, the parameters of clinical observations, antibodies and inflammatory factors in peripheral blood and cerebrospinal fluid (CSF) were detected. And the pathological changes in major organs were used to determine the patho-inflammatory reactions during the immune responses elicited by vaccination. RESULTS: The neutralizing antibodies of vaccine group reach to 1:32. There was no obvious changes of inflammatory factors in peripheral blood and CSF of monkeys challenged or unchallenged by live virus. In peripheral blood of unvaccinated group, the level of basophilic granulocyte higher 4 - 5 times than normal level and the interferon-γ (IFN-γ) showed obvious increase. Live virus infected after 7 days, the interleukin-6 (IL-6) and IFN-γ in peripheral blood of unvaccinated group (18.5, 12.7 pg/ml) were higher than vaccinated group (10.2, 7.6 pg/ml). Furthermore, the IL-6 in CSF (102.0 pg/ml) had 4 - 5 times increased than vaccinated group (12.4 pg/ml) at 7 days after virus exposure. Meanwhile, the pathological analysis revealed that no obvious changes were detected in CNS and other organs of vaccinated monkeys challenged with live virus. However, the pathological damages induced by virus infection could be determined in the unvaccinated control monkeys, including neuronal damage, massive cellular infiltration associated with pulmonary edema/hemorrhage and pulmonary/bronchial damage due to an infiltration of inflammatory cells. CONCLUSION: Capable of inducing an immune response, the EV71 inactivated vaccine offers protection to neonatal rhesus monkeys against the attacks of live virus. Based on the results of no patho-inflammatory reaction and pathological damage after viral infection in vaccinated animals, the excellent safety of this vaccine may be confirmed in neonatal monkey.