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Objective To clarify the expression and distribution of brain⁃derived neurotrophic factor (BDNF) in the cerebrum of plateau yaks and cattle, and to explore the relationship between BDNF function and the adaptability of altitude hypoxia. Methods Five yaks and five cattles were selected.The content and distribution of BDNF in frontal lobe, temporal lobe, parietal lobe, occipital lobe, cerebrum white matter and hippocampus of yak and cattle were analyzed by Real⁃time PCR, Western blotting and Immunohistochemistry. Results Real⁃time PCR result showed that BDNF mRNA expression in the cerebrum of yaks and cattles was highest in temporal cortex, followed by hippocampus, parietal cortex, occipital cortex and frontal cortex, and lowest in white matter. Western blotting results showed that the content of BDNF protein in the cerebrum of yaks was the highest in temporal cortex,followed by hippocampus. The content of BDNF protein in other tissues was parietal cortex, frontal cortex and cerebrum white matter, and the content of BDNF protein was the lowest in occipital cortex. The content of BDNF protein intlecerebrum of cattles was the highest in the temporal cortex, followed by the hippocampus. The content of BDNF protein in other tissues was parietal cortex, occipital cortex and frontal cortex in descending order, and the protein content in cerebrum white matter was the lowest. Immunohistochemical results showed that the positive expression of BDNF protein in the cerebrum of yaks and cattles was basically similar, mainly distributed in the granulosa cells and glial cells in the frontal cortex, temporal cortex, parietal cortex and occipital cortex, glial cells in cerebrum white matter, pyramidal cell layer and polyform cell layer in the hippocampus. There was the small amount of distribution in Martinotti cells and the molecular layer of hippocampus in the cerebral cortex. Conclusion BDNF mRNA and protein are distributed and expressed in different brain regions of yaks and cattles, but the expression level different, which is speculated to be closely related to the specific functions of different cerebrum regions. The expression level of the cerebrum of yak is higher than that of cattle except occipital cortex, suggesting that it is related to the altitude hypoxic environment. BDNF may play an important role in enhancing hypoxic tolerance and protecting internal environmental homeostasis in the process of animal adaptation to hypoxic environment.
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Objective To explore the expression and distribution characteristics of vascular endothelial growth factor-B(VEGF-B) in diencephalon and brainstem of Yak’s brain tissues, and to investigate the associations between its expression and hypoxia adaptation. Methods Five healthy yaks were selected, and the brain tissues were divided and collected according to the gross anatomical structure of the brain, including pituitary, thalamus, hypothalamus, oblongata and pons. The characteristics of expression and location of VEGF-B in different regions of Yak’s brain tissues were detected by Real-time PCR, Western blotting and immunohistochemical techniques. Results The results showed that the highest expression level of VEGF-B mRNA of yak brain tissue was in the pituitary, and the content was significantly higher than that found in other parts of the brain(P<0. 05). Following the expressions were in the hypothalamus, thalamus and medulla oblongata, while the lowest expression level was in pons. The expression level of VEGF-B protein in Yak’s brain tissue was similar to the mRNA expression level except that the thalamus was higher than that of hypothalamus. The result of immunohistochemistry showed that VEGF-B protein-positive substances were mainly distributed in the cytoplasm of various types of cells. Among them, the positive staining of VEGF-B was mainly concentrated in eosinophils of pituitary. The positive staining of VEGF-B was mainly concentrated in pleomorphic cells of thalamus and hypothalamus. The distribution of VEGF-B protein-positive substances were mainly focused in nerve cell body of medulla oblongata and pons. Conclusion VEGF-B protein is expressed in both diencephalon and brainstem of yak, which may be closely related to its functions of anti-apoptosis, "survival factor" and angiogenesis. However, the specific mechanism of its neuroprotective effect on Yak brain under hypoxic environment needs to be further studied. The difference of expression in different regions may be related to the tissue specificity and function in different regions of the brain.
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Objective Saiga antelope is a small population inhabiting in desert and semi desert areas of national and world endangered protected animals, its wild population is extremely rare. In order to explore the correlation between hypoxic tolerance and neuroglobin (NGB) in Saiga antelope. A female Saiga antelope died of dystocia was used as the experimental animal, and the tissue samples were sampled repeatedly for 3 times to study the distribution and expression of NGB in brain of Saiga antelope in the process of adapting to hypoxia. Methods The distribution and expression of NGB in the parietal lobe, frontal lobe, temporal lobe, occipital lobe, hypothalamus, hippocampus, pear like leaf, cingulate gyrus, striatum and thalamus of Saiga antelope were detected by immunohistochemistry(IHC) and Real-time PCR. Results The result of IHC showed that NGB was positive in all parts of Saiga antelope brain, and the cells that had positive reactions in the parietal, frontal, temporal and occipital lobes of the cerebral cortex were mostly granular cells and martinotti cells. NGB was found in the granular cell layer, pyramidal cell layer and molecular cell layer in hippocampus, and the positive staining of pyramidal cell layer was the strongest. NGB positive expression in Pear like leaves and hypothalamus mainly occured in multi-type cells. NGB was expressed in the granulocytes and glial cells of cingulate gyrus, mainly in the granular cells. The positive expression of NGB in striatum was mainly located in granular cells, the positive expression of NGB in thalamus could be seen in the polymorphosis and glial cells, and the positive substance of the multi-type cells was obviously colored. The result of Real-time PCR showed that NGB was expressed in different regions of Saiga antelope brain, the highest expression in the frontal lobe of the cerebral cortex, the second in the parietal lobe, and the expression was significantly higher than that in the rest of the brain tissue (P0.05). Conclusion The expression of NGB in different regions of Saiga antelope has some selective differences in the long-term adaptation to hypoxia environment. The frontal and parietal lobes have the highest tolerance to hypoxia, followed by hippocampus, and the striatum is the weakest, which may be related to the specific functions of different regions of brain tissue, but the specific mechanism remains to be further explored.
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Cyclic adenosine monophosphate(cAMP)is a “second messenger” that regulates cell signal transduction. Adenylyl cyclases(ACs)and phosphodiesterases(PDEs)can directly regulate cAMP level in cells and then regulate the downstream signaling pathways. Increasing intracellular cAMP level can inhibit inflammation and enhance smooth muscle relaxation, which is an effective strategy for the prevention and treatment of chronic obstructive pulmonary disease(COPD). This paper briefly summarizes the signaling pathways regulating cAMP and their mechanisms and related drugs in COPD therapy, hoping to provide references for further research and development of new target drugs which regulate cAMP for the prevention and treatment of COPD.
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Objective:To observe the effects of Da Chaihutang on Cyclic adenosine monophosphate （cAMP）-response element binding protein （CREB）/peroxisome proliferator-activated receptor-gamma coactivator-1 alpha （PGC-1<italic>α</italic>） pathway in nutritionally obese rats and the protective mechanism on liver mitochondria. Method:A total of 120 8-week-old male SD rats were randomly divided into a control group （<italic>n</italic>=20） and an experimental group （<italic>n</italic>=100）. The rats in the control group were fed on a normal diet， while those in the experimental group were administered with a high-fat feed. Successfully modeled rats were randomly divided into a model group， a positive drug （metformin） group， and low-， medium- and high-dose Da Chaihutang groups （4.25， 8.5， and 17 g∙kg<sup>-1</sup>， respectively）， with 20 rats in each group. After treatment with Da Chaihutang， the body weight， Lee's index， liver mitochondrial membrane potential and mitochondrial ultrastructure， PGC-1<italic>α </italic>expression and CREB phosphorylation of each group were measured and compared. Result:Compared with the control group， the model group showed increased body weight and Lee's index （<italic>P</italic><0.01）， whereas decreased mitochondrial membrane potential， PGC-1<italic>α</italic> expression， and CREB phosphorylation level （<italic>P</italic><0.01）. As compared with the model group， Da Chaihutang significantly reduced the body weight and Lee's index of obese rats （<italic>P</italic><0.05， <italic>P</italic><0.01）， enhanced liver mitochondrial membrane potential （<italic>P</italic><0.05， <italic>P</italic><0.01） to protect the integrity of mitochondrial structure， up-regulated PGC-1<italic>α</italic> expression and promoted CREB phosphorylation （<italic>P</italic><0.05， <italic>P</italic><0.01）. Conclusion:Da Chaihutang protects the structure and function of mitochondria and inhibits weight gain in obese rats by activating the CREB/PGC-1<italic>α</italic> pathway.
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45 strains of Lactobacillus were isolated from 17 samples of traditional fermented milk in Gobi region of Mongolia. Based on morphological, physiological, biochemistry test and 16S rDNA sequencing analysis, identified as 31 strains of Lactobacillus fermentum(L. fermentum), 12 strains of L. helveticus, one strain of L. plantarum and one strain of L. casei. Survival rate of IMAU20085 is 81.44% in the screening experiment of resistance to the artificial gastric juice (pH 3.0). The isolation and identification of these strains and the screening of high acid-tolerant strains have important meaning to the preservation and exploitation of probiotic resource.