Expression and distribution of brain⁃derived neurotrophic factor in different cerebrum regions of yak and cattle / 解剖学报

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.

Wenxiao Powder Alleviates Depression by Promoting Neurogenesis via BDNF/TrkB/ERK/CREB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo decipher the mechanism of Wenxiao powder in alleviating corticosterone-induced depression-like behaviors in mice. MethodMale ICR mice were randomized into normal， model， paroxetine （20 mg·kg-1）， and low- and high-dose （3.27， 6.54 g·kg-1， respectively） Wenxiao powder groups. The mice in normal and model groups received equal volume of saline. Other groups except the normal group were injected with corticosterone subcutaneously 0.5 h after gavage to induce depression. Mice were tested for depression-like behaviors after drug administration. Enzyme-linked immunosorbent assay （ELISA） was performed to measure the corticosterone content in the serum. Nissl staining was performed to observe the damage of hippocampal neurons. Immunofluorescence staining was employed to observe the expression of double cortin （DCX） in the dentate gyrus （DG） of the hippocampus. Western blot was employed to determine the expression of proteins in the brain-derived neurotrophic factor （BDNF）/tyrosine kinase receptor B （TrkB）/extracellular signal-regulated kinase （ERK）/cAMP-response element-binding protein （CREB） pathway in the hippocampus. ResultCompared with the normal group， the model group showed decreased sucrose preference rate， increased immobility time in the tail suspension test （P<0.01）， and reduced residence time in the central area of the open field and the total movement distance （P<0.05， P<0.01）. In addition， the modeling elevated the corticosterone level in the serum （P<0.01）， decreased the volume and intensified the nuclear staining of hippocampal neurons in the DG area， reduced the expression of DCX in the DG area， and down-regulated the protein levels of BDNF， phosphorylated （p）-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. Compared with the model group， low-dose Wenxiao powder improved the mouse behavivors in the sucrose preference， open field， and tail suspension tests （P<0.05， P<0.01）， and high-dose Wenxiao powder improved the behaviors in the sucrose preference and open field tests （P<0.05， P<0.01）. In addition， Wenxiao powder lowered the serum corticosterone level （P<0.01） and recovered the structure and morphology of neurons with obvious nuclei and presence of Nissl bodies in the DG area of the hippocampus. Moreover， Wenxiao powder at both doses promoted the expression of DCX in the DG area， and high-dose Wenxiao powder up-regulated the protein levels of BDNF， p-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. ConclusionWenxiao powder can alleviate corticosterone-induced depression-like behaviors and promote neurogenesis in mice possibly by activating the BDNF/TrkB/ERK/CREB signaling pathway.

Electroacupuncture Promotes Functional Recovery after Facial Nerve Injury in Rats by Regulating Autophagy via GDNF and PI3K/mTOR Signaling Pathway / 中国结合医学杂志

OBJECTIVE@#To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway.@*METHODS@#Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR.@*RESULTS@#The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01).@*CONCLUSIONS@#EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.

Expression of GDNF and AR in Testicular Peritubular Cells of Surgery-induced Cryptorchidism Mice / 中山大学学报(医学科学版)

ObjectiveTo investigate the expression of glial cell line-derived neurotrophic factor （GDNF） and androgen receptor （AR） in testicular peritubular cells （TPCs） of cryptorchidism mouse models and explore the theoretical significance of cryptorchidism-induced spermatogenesis dysfunction. MethodsA total of 30 five-week-old male ICR rats were divided randomly by using random number table method into 6 groups. Cryptorchidism was surgically induced in 3 randomly selected groups and the other 3 groups underwent sham surgery as the control groups. On days 4， 7 and 14 after surgery， we harvested the mice testes of the 3 groups and their corresponding control groups， then measured the testicular volumes， analyzed the testicular histopathology and detected the mRNA and protein expression levels of AR and GDNF in TPCs by immunofluorescence， real-time PCR and Western blot. ResultsIn normal control groups， on days 4， 7 and 14 after surgery， the testicular volumes were （125.58±19.22） mm3，（123.45±20.12） mm3， （140.09±13.62） mm3 ， respectively. Clear layers of spermatogenic cells were well arranged and abundant sperm cells were found. Peritubular cells were morphologically homogeneous， with slim-spindle appearance and normal cell thickness. The mRNA expression levels of AR were 1.00±0.05， 1.06±0.07 and 1.19±0.13； GDNF mRNA 1.00±0.04， 1.09±0.05， and 1.10±0.07. The protein expression levels of AR were 1.01±0.01， 0.79±0.02 and 1.01±0.04； GDNF protein （18.68±0.43） pg/mL， （14.39±0.36） pg/mL and （16.88±0.37） pg/mL. In cryptorchidism groups， on days 4， 7 and 14 after surgery， the testicular volumes were （115.64±3.91） mm3， （69.51±14.97） mm3 and （44.86±5.56） mm3， respectively. Spermatogenic cells were disorganized， seminiferous tubules were disrupted， peritubular cells shrank， bent and fractured. The mRNA expression levels of AR were 0.76±0.06， 0.53±0.04， and 0.29±0.02； GDNF mRNA 0.72±0.05， 0.42±0.02 and 0.30±0.03. The protein expression levels of AR were 0.54±0.02， 0.98±0.04 and 0.31±0.01； GDNF protein （8.50±0.34） pg/mL， （17.44±0.32） pg/mL and （6.83±0.34） pg/mL. Statistically significant differences （P < 0.05） were found in 7-day and 14-day testicular volumes between control and cryptorchidism groups but not in the 4-day testicular volume （P > 0.05）. Testicular volumes， AR and GDNF mRNA and protein expression in control groups had no statistically significant difference （P > 0.05）， while those in cryptorchidism groups showed a trend of gradual decline in the amount and the differences between groups were statistically significant （P < 0.05）. ConclusionsIn surgery-induced cryptorchidism mice， after the induction， the expression of AR and GDNF in TPCs showed a gradual decrease over time. AR and GDNF play a major role in mediating the TPCs damage in cryptorchidism. This study provides a theoretical basis for mechanism researches of cryptorchidism-induced spermatogenesis dysfunction.

Wenyang Jieyu Prescription Regulates Hippocampal Neuron Apoptosis and Improves Synaptic Plasticity in Depressed Mice via BDNF/Akt/mTOR Pathway / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of Wenyang Jieyu prescription in regulating hippocampal neuron apoptosis and improving synaptic plasticity in the mouse model of depression induced by maternal separation combined with restraint stress. MethodThe mice on postnatal day 0 （PD0） were randomly assigned into a control group （n=10） and a modeling group （n=50）. Maternal separation combined with restraint stress was adopted to establish the mouse model of depression， and the modeled mice were randomized into model， Wenyang prescription， Jieyu prescription， Wenyang Jieyu prescription， and fluoxetine groups （n=10） on the weaning day （PD21）. From PD21 to PD111， the mice were fed with the diets mixed with corresponding medicines. The sucrose preference test， open field test， O-maze test， and novel object recognition test were then conducted to evaluate the depression， memory， and learning abilities of mice. Immunohistochemistry （IHC） was employed to measure the atomic absorbance （AA） of postsynaptic density protein 95 （PSD95） in the hippocampus. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to detect the apoptosis of hippocampal neurons. Western blot was employed to determine the protein levels of brain-derived neurotrophic factor （BDNF）， phosphorylated tyrosine kinase receptor B/tyrosine kinase receptor B （p-TrkB/TrkB）， phosphorylated protein kinase B/protein kinase B （p-Akt/Akt）， phosphorylated mammalian target of rapamycin/mammalian target of rapamycin （p-mTOR/mTOR）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X （Bax）， cysteinyl aspartate-specific proteinase-3 （Caspase-3）， synaptophysin （Syn）， and PSD95. ResultCompared with the control group， the modeling decreased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.01）. Furthermore， it decreased the expression of PSD95， increased the neuron apoptosis in the hippocampus （P<0.01）， down-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and up-regulated the protein levels of Bax and Caspase-3 （P<0.05） in the hippocampus. Compared with the model group， Wenyang Jieyu prescription and fluoxetine increased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.05， P<0.01）. Moreover， the drugs increased the expression of PSD95， reduced the neuron apoptosis （P<0.01）， up-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and down-regulated the protein levels of Bax and Caspase-3 （P<0.01）. ConclusionWenyang Jieyu prescription outperformed Wenyang prescription and Jieyu prescription in the treatment of the depressive behavior induced by maternal separation combined with restraint stress in mice. It exerted the therapeutic effect by reducing the hippocampal neuron apoptosis and improving the synaptic plasticity via the BDNF/Akt/mTOR pathway.

Syndromes and Mechanisms of Depression Induced by Second Hit in Mice / 中国实验方剂学杂志

ObjectiveTo explore the syndromes and mechanisms of depression induced by maternal separation （MS） combined with chronic restraint stress （RS） in mice. MethodOn postnatal day 0 （PD0）， the offspring mice were randomized into a blank group （NC） and a modeling group. The mouse model of depression was established by MS+RS for 21 days. After removal of female mice on PD21， the modeled mice were randomized into model， Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups， with 15 mice in each group. The sucrose preference， tail suspension， and open field tests were carried out to evaluate the anxiety and depression-like behavior in mice. Enzyme-linked immunosorbent assay was used to measure the adrenocorticotrophic hormone （ACTH） and corticosterone （CORT） levels in mouse plasma. High performance liquid chromatography-electrochemical detector was used to determine the content of monoamine neurotransmitters in the hippocampus. Real-time fluorescence quantitative polymerase chain reaction was employed to determine the mRNA levels of genes in the 5-hydroxytryptamine （5-HT） system， hypothalamic-pituitary-adrenal （HPA） axis， and brain-derived neurotrophic factor （BDNF） signaling pathway in the hippocampus. Immunohistochemistry was employed to determine the expression levels of proteins in the 5-HT system and HPA axis in the hippocampus. The Simple Western system was used to determine the protein levels of BDNF and tyrosine kinase receptor B （TrkB） in the hippocampus. ResultCompared with the NC group， the model group exhibited depression-like behavior， which was significantly relieved by Wenyang Jieyu prescription and fluoxetine. Compared with the NC group， the model group showed elevated levels of CORT and ACTH in the plasma （P<0.01）， which， however， were lowered by Wenyang Jieyu prescription and fluoxetine （P<0.05， P<0.01）. Compared with the NC group， the model group showed inhibited expression of neurotransmitters in the hippocampus （P<0.05， P<0.01）， while Wenyang Jieyu prescription and fluoxetine restored the expression of neurotransmitters （P<0.05， P<0.01）. Compared with NC group， the model group showed inhibition of the 5-HTergic nerve and abnormal activation of the HPA axis， and Wenyang Jieyu prescription and fluoxetine regulated the abnormal state of the 5-HTergic nerve and HPA axis. Compared with NC group， the modeling down-regulated the mRNA and protein levels of BDNF and TrkB in the hippocampus （P<0.05， P<0.01）， which， however， were recovered in Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups （P<0.05， P<0.01）. ConclusionThe mouse model of depression induced by MS+RS may present the syndrome of Yang deficiency and liver depression. Wenyang Jieyu prescription may increase the content of hippocampal neurotransmitters by regulating the 5-HT system and the BDNF signaling pathway mediated by the HPA axis， thereby alleviating depression-like behavior in mice.

Protective effect of brain-derived neurotrophic factor on retinal neurovascular unit / 国际眼科杂志(Guoji Yanke Zazhi)

Based on the neurovascular unit(NVU), neurovascular coupling functions as a barrier to maintain the homeostasis of the microenvironment by regulating the signaling and metabolic activity of nerve cells and capillaries. Widely dispersed across the retina, the NVU is essential to preserving its normal physiological function. A disturbance in retinal neurovascular homeostasis produced by a range of factors can result in a variety of retinal disorders, such as diabetic retinopathy(DR), glaucoma, retinitis pigmentosa(RP)and age-related macular degeneration(ARMD). The retina also has a widespread distribution of brain-derived neurotrophic factor(BDNF), which functions to promote neuron growth and repair damage by binding to its receptor TrkB. In recent years, BDNF was found to play a protective role against damage in the early stage of retinal neurovascular homeostasis imbalance, often known as the neurodegenerative stage. It also helps to reduce the production of pro-angiogenic substances of neurological origin and offers a fresh approach for the early detection and treatment of associated eye disorders.

Asociación entre el polimorfismo Val66Met del gen BDNF y el desarrollo de disfunción ejecutiva en pacientes con cáncer de mama

Introducción. La disfunción ejecutiva asociada a quimioterapia es un efecto adverso del tratamiento antineoplásico convencional y afecta a un porcentaje considerable de personas. Se ha reportado que la presencia de ciertos polimorfismos en genes relevantes puede causar mayor susceptibilidad a padecerlo. Objetivo. Determinar la relación entre el polimorfismo Val66Met (196 G>A) del gen BDNF y el desarrollo de disfunción ejecutiva en mujeres con cáncer de mama tratadas con quimioterapia. Métodos. Se evaluaron a 73 pacientes mujeres con cáncer de mama para determinar disfunción ejecutiva antes y después de la quimioterapia. La evaluación fue realizada con la prueba INECO Frontal Screening (IFS). Se determinó el genotipo (GG=Val/Val, GA=Val/Met y AA=Met/Met) por PCR y secuenciamiento del gen BDNF. El análisis de asociación se realizó mediante el cálculo del odds ratio (OR). Resultados. El 13,7% (n = 10) de pacientes presentó el alelo A (GA y AA), además obtuvieron puntajes significativamente menores de la prueba IFS comparado con las homocigotas GG (p A) del gen BDNF y el desarrollo de disfunción ejecutiva en pacientes con cáncer de mama tratadas con quimioterapia; sin embargo, las portadoras del alelo A (Met) presentaron puntajes menores en la evaluación cognitiva.

Introduction. Chemotherapy-associated executive dysfunction is an adverse effect of conventional antineoplastic treatment that affects many patients. It has been reported that the presence of specific polymorphisms in key genes can cause a greater susceptibility to develop this condition. Objective. To determine the relationship between the Val66Met polymorphism (196 G>A) of the BDNF gene and the development of executive dysfunction in female patients with breast cancer treated with chemotherapy. Methods. 73 female breast cancer patients were evaluated for executive dysfunction before and after chemotherapy. The evaluation was carried out with the INECO Frontal Screening test (IFS). The genotype (GG=Val/Val, GA=Val/Met and AA=Met/Met) was determined by PCR and sequencing of BDNF gene. Association analysis was performed by calculating the Odds Ratio (OR) and by quantitative comparison. Results. 13.7% (n = 10) of the sample presented the allele A (GA and AA), which obtained significantly lower scores in the IFS test compared to the homozygous GG (p A) polymorphism of the BDNF gene and the development of executive dysfunction in patients with breast cancer treated with chemotherapy. However, patients with the allele A (Met) presented significant lower scores in the cognitive assessment.

Study on Role and Mechanism of Leptin and BDNF in DSS Induced Colitis in Mice / 胃肠病学

Background: Abnormal expression of leptin and brain⁃derived neurotrophic factor (BDNF) is an important link in the occurrence of ulcerative colitis (UC), but the mechanism of leptin and BDNF in UC is still unclear. Aims: To explore the effect and mechanism of leptin and BDNF in DSS induced colitis in mice. Methods: Thirty⁃six male 8⁃10 weeks healthy leptin⁃deficient ob mice and leptin⁃normal expressing wild type (WT) mice were selected and randomly divided into WT experimental group, ob experimental group, WT control group and ob control group. The mice in experimental groups were given 3% DSS solution for 7 days to induce colitis model, and the mice in control group were given distilled water. After modeling, disease activity index (DAI) score, colon length, behavior and visceral sensitivity were observed. The mRNA expressions of leptin and BDNF in colon and hippocampus were detected by real⁃time fluorescent quantitative PCR, and the protein expression of BDNF in colon was detected by Western blotting. Results: Compared with corresponding control groups, DAI score, visceral sensitivity in WT experimental group and ob experimental group were significantly increased (P< 0.05), mRNA and protein expressions of BDNF in colon were significantly increased (P<0.05). Compared with WT control group, anxiety and depression⁃like behavior were found in WT experimental group, mRNA expressions of leptin, BDNF in hippocampus were significantly decreased (P<0.05). Correlation analysis showed that anxiety was positively correlated with length of colon in WT experimental group (P<0.05), and negatively correlated with DAI score (P<0.05); depression, expression of BDNF mRNA in colon were negatively correlated with length of colon (P<0.05), and positively correlated with DAI score (P<0.05); leptin in hippocampus was positively correlated with anxiety (P<0.05), while was negatively correlated with depression (P<0.05); expression of BDNF mRNA in colon was negatively correlated visceral sensitivity (P<0.05). Conclusions: Colonic BDNF secretion is associated with leptin expression, and both may be involved in the DSS⁃induced colitis in mice by mediating anxiety, depression and visceral sensitivity.

Continuous and Intermittent Exercise Upregulates PGC-1α/ Irisin / BDNF Expression to Improve Obesity-induced Cognitive Impairment in Mice / 中国生物化学与分子生物学报

This study aimed to investigate the effects of exercise on prefrontal PGC-1α, Irisin, BDNF, oxidative stress, inflammation, and cognitive function in high-fat diet-induced obese mice, which may provide experimental evidence of exercise rehabilitation methods and target screening for obesity. Three-month-old male C57BL/ 6J wild-type mice were randomly divided into four groups: control, high-fat diet, high-fat diet with moderate intensity continuous training, and high-fat diet with high-intensity interval training group, with 10 mice in each group. The mice in the high-fat diet with moderate intensity continuous training group and the high-fat diet with high-intensity interval training group received 8 weeks of moderate-intensity continuous training or high-intensity interval training after 12-week high-fat feeding. Behavioral results showed that compared with the control group, reaction time of adhesive removal test was significantly increased (P<0. 01), and spontaneous alternation rate in Y-maze test and exploration time in the novel object recognition test were significantly decreased (P < 0. 01) in the high-fat diet group, indicating that high-fat diet led to cognitive dysfunction in mice. Results showed that compared with the control group, Nissl bodies dissolution and apoptosis were significantly increased (P<0. 01), levels of PGC-1α, Irisin, BDNF, IL-10, and T-SOD were significantly deceased (P<0. 05, P<0. 01), levels of IL-1β, TNF-α, NF-κB, cleaved Caspase-3, Bax/ Bcl-2, ROS, and MDA were significantly increased in the prefrontal lobe (P<0. 01), indicating that high-fat diet induced excessive inflammation, oxidative stress, and apoptosis, which were conducive to prefrontal lobe damage. Compared with the high-fat diet group, moderate intensity continuous or high-intensity interval training decresed reaction time of adhesive removal test (P<0. 01), increased spontaneous alternation rate of Y-maze test and exploration time of novel object recognition test (P<0. 05, P<0. 01), indicating that both continuous and interval training improved cognitive function in obese mice; meanwhile, Nissl bodies and levels of PGC-1α, Irisin, BDNF, IL-10, and T-SOD were significantly increased (P<0. 05, P<0. 01), and apoptosis and levels of IL-1β, TNF-α, NF-κB, cleaved Caspase-3, Bax/ Bcl-2, ROS, and MDA were significantly reduced in the prefrontal lobe (P<0. 01), indicating that both continuous and interval training alleviated obesity-induced inflammation, oxidative stress, and apoptosis in the prefrontal lobe. Both continuous and interval training significantly upregulated PGC-1α/ Irisin/ BDNF expression in the prefrontal lobe of obese mice, inhibited oxidative stress and inflammation, reduced apoptosis, and resulted in alleviating obesity-induced prefrontal lobe damage and cognitive dysfunction; morevover, interval training better than continuous.

Effects of estradiol on depressive-like behavior of ovariectomized rats and its possible mechanism / 解剖学报

Objective To examine the effect of estradiol (E2) treatment on ovariectomy (OVX) induced depressive-like behavior and possible mechanism by measuring inflammatory biomarkers levels oi interleukin-6 (IL-6) and tumor necrosis tactor-(x (TNF-ot) and brain-derived neurotrophic factor (BDNF) expression in amygdaia nucleus. Methods Thirty nine healthy aduit 缶male SD rats were randomly divided into three groups : sham operation group (SO), ovariectomized group (OVX) and ovariectomized estradiol treatment group (OVX + E2). After 6 weeks of E2 treatment, depressive like behavior was evaluated by opening field test (OFT) and sugar water preference test (SPT). The levels of inflammatory factors IL-6 and TNF-a in amygdala were measured by ELESA, and the expression of BDNF in rat amygdala was detected by immunohistochemical staining. Results The result of the SPT showed that OVX significantly decreased the sugar intake and sugar preference rate of rats, and E2 treatment significantly increased sugar water intake and sugar water preference rate of rats. The result of the OFT showed that OVX significantly decreased the numbers of crossing and rearing of rats, and reduced the time spent in the centre ; E2 treatment significantly increased the numbers of crossing and rearing of rats, and prolonged the time spent in the centre. ELESA and immunohistochemical analysis found the levels of IL-6 and TNF-a in amygdala increased significantly, while the average absorbance (AA) of BDNF in the amygdala reduced significantly (P<0.01 respectively) of rats in OVX group when compared with the SO group. And the levels of IL-6 and TNF-a in amygdala decreased significantly (P<0.01 respectively), while the A4 of BDNF increased significantly (P< 0.05) in the amygdala of rats in the OVX+EX group when compared with the OVX group. The difference was statistically significant. Conclusion E2 treatment improved depression-like behavior of OVX rats is partly due to increased antiinflammatory and activated the BDNF expression in amygdaloid nucleus, thus enhancing the neuroprotective effect of OVX rats.

Dexmedetomidine improving complete Freund's adjuvant-induced anxiety-like and depression-like behaviour by promoting the expression of brain-derived neurotrophic factor-tyrosin kinase receptor B in mice hippocampus / 解剖学报

Objective To study the effect of dexmedetomidine (DEX), an α2- adrenoceptor agonist, on the pain-related anxiety-like and depression-like behaviour induced by complete Freund' s adjuvant (CFA) injection and its possible regulatory mechanism. Methods Thirty-six ICR female mice were randomly divided into normal saline (NS) group, CFA group and DEX + CFA group, n = 12 for each group. Chronic inflammatory pain model was established by subcutaneous injection of 10 μl CFA into the right hind limb of mice. DEX + CFA group mice were injected intraperitoneally with 0.025 mg/kg DEX 30 minutes before nociceptive behavior test, and once a day for 7 days. Von-frey fiber was used to evaluate the threshold of mechanical pain in mice, n = 12 for each group. The anxiety-like behavior of mice were detected by open field test, n = 12 for each group. Sucrose preference, tail suspension test and forced swimming test were used to detected the depression-like behavior of mice, n = 12 for each group. The expression of adrenergic receptor β2 (ADRB2), Brain-derived neurotrophic factor (BDNF), tyrosine kinase B receptor (TrkB), and glutamate receptors 1 (GluR1) and GluR2 were detected by Western blotting, n = 8 for each group. Immunohistochemical staining was used to detect the expression of recombinant doublecortin(DCX), which is a marker of newborn neurons in the hippocampus, n = 4 for each group. Results Compared with the NS group, the mechanical threshold of mice on the 1st, 3rd and 7th day after CFA injection decreased significantly (P 0.05). Compared with the NS group, the time spent in the inner ares (P<0.01), number of entering the central grid area (P<0.01) and distance travelled in the inner area (P<0.01) of CFA group mice reduced significantly, while the time (P<0.01), numbers (P < 0.05) and distance (P < 0.05) of DEX + CFA group mice entering the central grid area enhanced significantly. The result of depression-like behavior tests showed that the sucrose preference percentage (P < 0.05) reduced significantly in CFA group when compared with NS group, and the immobility time increased significantly in tail suspension test (P<0.01) and forced swimming test (P< 0.001) in CFA mice when compared with NS group, while DEX intervention could significantly increase the sucrose preference scores (P<0.05) and decreased the immobility time in tail suspension test (P<0.05) and forced swimming test (P<0.05). The result of Western blotting showed that compared with the NS group, the levels of ADRB2 (P<0.0010), BDNF (P < 0.001), TrkB (P < 0.01), GluR1 (P < 0.001) and GluR2 (P < 0.001) in the hippocampus of CFA group were significantly decreased, while DEX intervention could significantly increase the expression of ADRB2 (P<0.05), BDNF (P < 0.001), TrkB (P < 0.001), GluR1 (P < 0.001) and GluR2 (P < 0.001). Immunohistochemical result showed that compared with the NS group, the average absorbance (AA) of DCX decreased significantly in hippocampus of CFA group (P<0.05), but increased significantly in DEX+CFA group (P < 0.05). Conclusion Dexmedetomidine may promote hippocampal neurogenesis through upregulated the expression of BDNF-TrkB, thus improving CFA-induced anxiety-like and depression-like behaviors in mice.

Effects of treadmill exercise on learning and memory of the vascular dementia rats and its mechanism / 解剖学报

Objective To observe the effects of 4-week low intensity treadmill exercise on the learning and memory, amino acid levels and the protein expression of protein kinase A ( PKA) , cyclic adenosine monophosphate response element binding protein( CREB) and brain-derived neurotrophic factor(BDNF) in the prefrontal cortex (PFC) of the vascular dementia (VD) rats. Methods Thirty-nine SD rats were randomly allocated to 3 groups, sham group (sham, n= 13) , vascular dementia group (VD, n= 13) and vascular dementia treaded with exercise group (VD + EX, n= 13). Chronic cerebral ischemia model in VD group and VD+EX group rats were established by permanent ligation of bilateral, then VD+EX group rats were submitted to 4-week low intensity treadmill exercise. After exercise, spatial learning and memory ability were evaluated by Moms water maze test ( MWM ) , glutamic ( Glu ) and gamma-aminobutyric acid (GABA) levels in the PFC were measured by high performance liquid chromatography( HPLC) ; the protein expression of PKA, CREB and BDNF in the PFC of rats were detected by Western blotting. Results The result of the MWM showed the average escape latency of rats in the VD group on the 1 -5 days was significantly higer than sham group, the time to first find the original platform was significantly prolonged and the platform crossings decreased significantly ( P 0. 05 ) between the two groups. Conclusion Four-week low-intensity running exercise improves the learning and memory ability of VD rats through enhancing the Glu level and activating PKA-CREB-BDNF signaling in the PFC of rats.

Nerve repair effect of olanzapine-mediated cyclic AMP response element binding protein/brain-derived neurotrophic factor/receptor tyrosine kinase receptors B pathway on schizophrenic rats / 解剖学报

Objective To stud)' the nerve repair effect of olanzapine on schizophrenia model rats through its effect on cyclic AMP response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF)/receptor tyrosine kinase receptors B (TrkB) pathway. Methods Total 60 rats were divided into control group, model group, olanzapine low, middle and high dose group. The rats in the model group, olanzapine low, middle and high dose groups were injected intraperitoneally with MK-801[0. 2 mg/(kg-d) ], while the control injected with the same amount of normal saline. The low, middle and high dose olanzapine groups were perfused with olanzapine solution of 0. 5 mg/(kg-d),1. 0 mg/(kg-d) and 1. 5 mg/(kg-d) respectively. The behavior of rats was scored according to ataxia and stereotyped behavior standards, cognitive function and learning ability were evaluated by Moms water maze test, serum tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6) levels were detected by ELISA method, hippocampal histopathology was observed under microscope, and apoptosis and expression of CREB/BDNF/TrkB pathway related proteins in hippocampus were detected. Results Compared with the control group, the ataxia, the score of stereotyped behavior, the expression of TNF-a, IL-6 and the rate of apoptosis in the model group increased significantly (P < 0 . 01). Compared with the control group, the number of crossing the platform, the time of staying in the target quadrant and the relative expression of CREB, p-CREB, p-TrkB, TrkB and BDNF protein in the model group decreased significantly (P<0. 01), and those in the low and middle dose olanzapine groups decreased significantly (P < 0 . 05). Compared with the model group, the times of crossing the platform and the stay time in the target quadrant increased significantly in the low and middle dose olanzapine groups (P< 0. 05). In the model group and the low dose olanzapine group, the hippocampal cells were swollen obviously, the nucleus was broken and divided, pyknosis, and the tissue aiTangement was disorderly, while the phenomenon of fragmentation and nuclear pyknosis was rarely seen in the middle and high dose olanzapine groups. Conclusion The nerve repair mechanism of olanzapine on schizophrenic model rats is related to improving cognitive impainnent, protecting hippocampal neurons and activating the expression of CREB/BDNF/TrkB signal pathway in rats.

Role and mechanism of glucagon-like peptide-1 in depression / 中国药理学通报

Glucagon-like peptide-1 (GLP-1) is a major hormone of incretin hormone and gut-brain axis, which is related to the control of energy homeostasis and the occurrence of obesity. In addition to suppressing appetite, GLP-1 has neuroprotective effects by acting on areas of the brain involved in stress response and mood regulation. Depression is a common mental disease, and GLP-1 is closely related to depression. This article reviews the role and mechanism of GLP-1 in depression.

MANF brakes TLR4 signaling by competitively binding S100A8 with S100A9 to regulate macrophage phenotypes in hepatic fibrosis

The mesencephalic astrocyte-derived neurotrophic factor (MANF) has been recently identified as a neurotrophic factor, but its role in hepatic fibrosis is unknown. Here, we found that MANF was upregulated in the fibrotic liver tissues of the patients with chronic liver diseases and of mice treated with CCl4. MANF deficiency in either hepatocytes or hepatic mono-macrophages, particularly in hepatic mono-macrophages, clearly exacerbated hepatic fibrosis. Myeloid-specific MANF knockout increased the population of hepatic Ly6Chigh macrophages and promoted HSCs activation. Furthermore, MANF-sufficient macrophages (from WT mice) transfusion ameliorated CCl4-induced hepatic fibrosis in myeloid cells-specific MANF knockout (MKO) mice. Mechanistically, MANF interacted with S100A8 to competitively block S100A8/A9 heterodimer formation and inhibited S100A8/A9-mediated TLR4-NF-κB signal activation. Pharmacologically, systemic administration of recombinant human MANF significantly alleviated CCl4-induced hepatic fibrosis in both WT and hepatocytes-specific MANF knockout (HKO) mice. This study reveals a mechanism by which MANF targets S100A8/A9-TLR4 as a "brake" on the upstream of NF-κB pathway, which exerts an impact on macrophage differentiation and shed light on hepatic fibrosis treatment.

Peripheral BDNF Regulates Somatosensory-Sympathetic Coupling in Brachial Plexus Avulsion-Induced Neuropathic Pain / 神经科学通报·英文版

Brachial plexus avulsion (BPA) is a combined injury involving the central and peripheral nervous systems. Patients with BPA often experience severe neuropathic pain (NP) in the affected limb. NP is insensitive to the existing treatments, which makes it a challenge to researchers and clinicians. Accumulated evidence shows that a BPA-induced pain state is often accompanied by sympathetic nervous dysfunction, which suggests that the excitation state of the sympathetic nervous system is correlated with the existence of NP. However, the mechanism of how somatosensory neural crosstalk with the sympathetic nerve at the peripheral level remains unclear. In this study, through using a novel BPA C7 root avulsion mouse model, we found that the expression of BDNF and its receptor TrκB in the DRGs of the BPA mice increased, and the markers of sympathetic nervous system activity including α1 and α2 adrenergic receptors (α1-AR and α2-AR) also increased after BPA. The phenomenon of superexcitation of the sympathetic nervous system, including hypothermia and edema of the affected extremity, was also observed in BPA mice by using CatWalk gait analysis, an infrared thermometer, and an edema evaluation. Genetic knockdown of BDNF in DRGs not only reversed the mechanical allodynia but also alleviated the hypothermia and edema of the affected extremity in BPA mice. Further, intraperitoneal injection of adrenergic receptor inhibitors decreased neuronal excitability in patch clamp recording and reversed the mechanical allodynia of BPA mice. In another branch experiment, we also found the elevated expression of BDNF, TrκB, TH, α1-AR, and α2-AR in DRG tissues from BPA patients compared with normal human DRGs through western blot and immunohistochemistry. Our results revealed that peripheral BDNF is a key molecule in the regulation of somatosensory-sympathetic coupling in BPA-induced NP. This study also opens a novel analgesic target (BDNF) in the treatment of this pain with fewer complications, which has great potential for clinical transformation.

Mechanism of bilobalide promoting neuroprotection of macrophages / 中国中药杂志

This study aims to explore the neuroprotective effect of bilobalide(BB) and the mechanisms such as inhibiting inflammatory response in macrophage/microglia, promoting neurotrophic factor secretion, and interfering with the activation and differentiation of peripheral CD4~+ T cells. BB of different concentration(12.5, 25, 50, 100 μg·mL~(-1)) was used to treat the RAW264.7 and BV2 cells for 24 h. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay and cell counting kit-8(CCK-8) were employed to detect the cytotoxicity of BB and appropriate concentration was selected for further experiment. Lipopolysaccharide(LPS) was applied to elicit inflammation in RAW264.7 and BV2 cells, mouse bone marrow-derived macrophages(BMDMs), and primary microglia, respectively. The effect of BB on cell proliferation and secretion of inflammatory cytokines and neurotrophic factors was detected by enzyme-linked immunosorbent assay(ELISA). Spleen monocytes of C57BL/6 female mice(7-8 weeks old) were isolated, and CD4~+ T cells were separated by magnetic beads under sterile conditions. Th17 cells were induced by CD3/CD28 and the conditioned medium for eliciting the inflammation in BMDMs. The content of IL-17 cytokines in the supernatant was detected by ELISA to determine the effect on the activation and differentiation of CD4~+ T cells. In addition, PC12 cells were incubated with the conditioned medium for eliciting inflammation in BMDMs and primary microglia and the count and morphology of cells were observed. The cytoto-xicity was determined by lactate dehydrogenase(LDH) assay. The result showed that BB with the concentration of 12.5-100 μg·mL~(-1) had no toxicity to RAW264.7 and BV2 cells, and had no significant effect on the activity of cell model with low inflammation. The 50 μg·mL~(-1) BB was selected for further experiment, and the results indicated that BB inhibited LPS-induced secretion of inflammatory cytokines. The experiment on CD4~+ T cells showed that the conditioned medium for LPS-induced inflammation in BMDMs promoted the activation and differentiation of CD4~+ T cells, while the conditioned medium of the experimental group with BB intervention reduced the activation and differentiation of CD4~+ T cells. In addition, BB also enhanced the release of neurotrophic factors from BMDMs and primary microglia. The conditioned medium after BB intervention can significantly reduce the death of PC12 neurons, inhibit neuronal damage, and protect neurons. To sum up, BB plays a neuroprotective role by inhibiting macrophage and microglia-mediated inflammatory response and promoting neurotrophic factors.

Ginsenoside Rg1 injection combined with inosine tablets and vitamin B1 for the treatment of primary retinitis pigmentosa / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the effects of ginsenoside Rg1 injection combined with inosine tablets and vitamin B1 on serum brain-derived neurotrophic factor(BDNF), pituitary adenylate cyclase activating polypeptide(PACAP)and clinical efficacy in primary retinitis pigmentosa.METHODS: A total of 50 patients(100 eyes)with primary retinitis pigmentosa who admitted to the Department of Ophthalmology, the Second Affiliated Hospital of Hebei North University from August 2019 to March 2022 were selected as the research object. They were divided into the study group and the control group according to random number table, with 50 eyes in each group. Patients in the control group were treated with inosine tablets and vitamin B1, while patients in the study group were treated with ginsenoside Rg1 injection on the basis of the control group. The expression of BDNF and PACAP in serum, electroretinogram and spectral-domain optical coherence tomography(SD-OCT)were compared before and after treatment, and the retinal thickness(RT), mean deviation(MD), clinical efficacy and safety indexes were compared between the two groups.RESULTS: There were no differences in the MD of the two groups before treatment(t=1.670, P=0.098), while the MD of the study group was significantly lower than that of the control group after treatment(t=3.628, P&#x003C;0.01). Before treatment, RT with a diameter of 1mm at the circle of macular fovea was compared between the two groups(t=0.108, P=0.914), it was significantly higher than that in the control group after treatment(t=6.125, P&#x003C;0.01). Before treatment, there was no significant difference in the results of dark adaptation of electroretinogram between the two groups(all P&#x003E;0.05). After treatment, the results of dark adaptation in the study group were significantly better than those in the control group(all P&#x003C;0.01). Before treatment, there was no significant difference in the results of electroretinogram adaptation between the two groups(all P&#x003E;0.05). After treatment, the results of electroretinogram adaptation in the study group were significantly better than those in the control group(all P&#x003C;0.01). There was no significant difference in BDNF and PACAP between the two groups before treatment(all P&#x003E;0.05). BDNF and PACAP in the study group were higher than those of the control group after treatment(all P&#x003C;0.01). After treatment, no adverse reactions were observed in both groups.CONCLUSION: The treatment of patients with primary retinitis pigmentosa with ginsenoside will improve the retinal function and promote the prognosis of the disease by regulating the expression of BDNF and PACAP, and it is highly safe.

Effects of mesencephalic astrocyte-derived neurotrophic factor on sepsis-associated acute kidney injury / 世界急诊医学杂志（英文）

@#BACKGROUND: To determine the protective role of mesencephalic astrocyte-derived neurotrophic factor (MANF) in regulating sepsis-associated acute kidney injury (S-AKI). METHODS: A total of 96 mice were randomly divided into the control group, control+MANF group, S-AKI group, and S-AKI+MANF group. The S-AKI model was established by injecting lipopolysaccharide (LPS) at 10 mg/kg intraperitoneally. MANF (200 μg/kg) was administered to the control+MANF and S-AKI+MANF groups. An equal dose of normal saline was administered daily intraperitoneally in the control and S-AKI groups. Serum and kidney tissue samples were obtained for biochemical analysis. Western blotting was used to detect the protein expression of MANF in the kidney, and enzyme-linked immunosorbent assay (ELISA) was used to determine expression of MANF in the serum, pro-inflammatory cytokines (tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]). Serum creatinine (SCr), and blood urea nitrogen (BUN) were examined using an automatic biochemical analyzer. In addition, the kidney tissue was observed for pathological changes by hematoxylin-eosin staining. The comparison between two groups was performed by unpaired Student’s t-test, and statistics among multiple groups were carried out using Tukey’s post hoc test following one-way analysis of variance (ANOVA). A P-value <0.05 was considered statistically significant. RESULTS: At the early stage of S-AKI, MANF in the kidney tissue was up-regulated, but with the development of the disease, it was down-regulated. Renal function was worsened in the S-AKI group, and TNF-α and IL-6 were elevated. The administration of MANF significantly alleviated the elevated levels of SCr and BUN and inhibited the expression of TNF-α and IL-6 in the kidney. The pathological changes were more extensive in the S-AKI group than in the S-AKI+MANF group. CONCLUSION: MANF treatment may significantly alleviate renal injury, reduce the inflammatory response, and alleviate or reverse kidney tissue damage. MANF may have a protective effect on S-AKI, suggesting a potential treatment for S-AKI.