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BACKGROUND: The mechanism of electroacupuncture on multi-acupoints in the treatment of peripheral facial paralysis is still unknown. Glial cell-derived neurotrophic factor (GDNF) is currently the most effective factor in promoting the survival of motoneurons in vitro, and the PI3K/AKT pathway plays an important role in protecting damaged motoneurons. There is yet no research on GDNF/PI3K/AKT pathway involved in electroacupuncture promoting facial nerve regeneration in rabbits. OBJECTIVE: To observe the effect of electroacupuncture on regeneration after peripheral facial nerve crush injury, and to explore the protective mechanism of electroacupuncture on facial motoneurons through the GDNF/PI3K/AKT signaling pathway. METHODS: Sixty-six adult healthy New Zealand white rabbits provided by the Animal Experimental Center of Southwest Medical University were randomly divided into a normal group and a model group. The facial nerves on the right side in the model group were subjected to a crush injury. Then the animal models were randomly divided into a model control group and an electroacupuncture group. Animals in the model control group recovered naturally, while those in the electroacupuncture group underwent electroacupuncture at Yifeng, Jiache, Sibai, Dicang, Yangbai, and Quanliao acupoints daily for 30 minutes. The improvement of facial paralysis symptoms in experimental animals were observed and scored. Tissue samples were directly taken form the normal group, and pons tissues with facial neurons were taken in the model group at 1, 4, 7, 14, and 28 days postoperatively. The morphologies of facial motoneurons and Nissl bodies were observed by hematoxylin-eosin staining and Nissl staining, respectively. Immunohistochemical techniques and western blot assay were used to detect the protein expression of GDNF, PI3K, AKT, and p-AKT in the facial motoneurons. The study protocol was approved by the Animal Ethics Committee of Southwest Medical University with approval No. 20170120001. RESULTS AND CONCLUSION: The symptoms of facial paralysis were that the animal’s mouth was drooped at the affected side, with lodging tentacles and the movement being weakened, and the eyelids that could not be lifted, which recovered faster and more completely in the electroacupuncture group than the model control group. The morphological changes of facial neurons and changes of Nissl bodies in the electroacupuncture group were lighter than those in the model control group. At each time point postoperatively, the stronger GDNF immune response could be seen in the electroacupuncture group, and the number of GDNF-positive cells was higher than that of the model control group except 1 day postoperatively (P < 0.001). The expressions of GDNF, PI3K, p-AKT proteins in the facial motoneurons were significantly increased in the electroacupuncture group compared with the model control group (P < 0.05; P < 0.01; P < 0.001). To conclude, electroacupuncture can effectively treat the peripheral facial paralysis caused by the crushed injury of facial nerve and promote the recovery of facial neurons. The up-regulation of GDNF expression in the facial motoneurons and the activation of PI3K/AKT signaling pathway may be the underlying protective mechanism of electroacupuncture.
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Objective To explore the effect of the retinoic acid (RA) on the apoptosis of neurons caused by hypoxic ischemic brain damage (HIBD).Methods Seventy-two newborn Sprague-Dawley rats were randomly divided into an RA deficiency (RAD) group,an RA normal (RAN) group and a control group,each of 24.The HIBD model was established in the RAD and RAN groups using Rice's method.The left common carotid artery was exposed,ligated and cut,inducing hypoxia.In the control group the left common carotid artery was exposed without any other treatment.Three and 7 days after the operation,neuron apoptosis in the brain tissue was evaluated using TUNEL staining.The degree of HIBD was quantified using modified neurological severity scores (mNSS) 7,14,21 and 28 days after the operation.Primary neurons were cultured in vitro,and oxygen glucose deprivation (OGD) was induced,then control,OGD and RA+ OGD groups were formed.The gene transcription and the protein activity of retinoic acid receptor alpha (RARcα),GDNF (glial cell line-derived neurotrophic factor) and Caspase-8 were examined with polymerase chain reactions (PCR) and Western blotting.The RA+OGD group was exposed to RA and SiRNA adenovirus,and divided into a silenced group and a negative transfection group according to the infection.Results The average mNSS of the RAD group was significantly higher than that of the RAN group.TUNEL staining showed that the apoptotic cells in the cortex increased from day 3 to 7 after the operation,but significantly more in the RAD group than in the RAN group.The gene transcription and protein activity of RARα and GDNF in the RA+OGD group were significantly higher than in the OGD group,and those of Caspase-8 were significantly lower.The gene transcription and protein activity of RARα and GDNF in the silenced group were significantly lower than in the negative transfection group,while those of Caspase-8 were just the opposite.Conclusion RA can inhibit the apoptosis of primary neurons after HIBD by up-regulating the expression of GDNF and down-regulating that of Caspase-8 via RARα.
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<p><b>OBJECTIVE</b>To investigate the potential alleviating effects of acupuncture on maternal separation (MS)-induced changes in plasma pro-inflammatory cytokine levels of rat pups.</p><p><b>METHODS</b>On postnatal day 15, rat pups were randomly assigned to 4 groups (n=6 per group) using a random number table: normal, MS, MS with acupuncture stimulation at Shenmen (HT 7) acupoint (MS+HT 7), and MS with acupuncture stimulation at Chengshan (BL 57) acupoint (MS+BL 57) groups. Rat pups in the normal group were housed with their mothers under standard conditions; those in the MS, MS+HT 7 and MS+BL 57 groups were maternally separated and individually maintained. Acupuncture stimulation was performed at HT 7 or BL 57 acupoints once a day for 7 consecutive days. A tail suspension test was performed to measure immobility time of rats and the plasma was collected on postnatal day 21, then levels of corticosterone (CORT), interleukin (IL)-1β, IL-6 and glial cell-derived neurotrophic factor (GDNF) in plasma were measured.</p><p><b>RESULTS</b>Compared with the normal group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF in the MS group were significantly increased (P<0.05 or P<0.01). Compared with the MS group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF were significantly reduced in the MS+HT 7 group (P<0.05 or P<0.01). Moreover, the immobility time and plasma levels of IL-1β and IL-6 in the MS+HT 7 group were significantly lower than those in the MS+BL 57 group (P<0.05).</p><p><b>CONCLUSION</b>Acupuncture stimulation at HT 7 can alleviate the behavioral impairment and changes of the cytokines by MS, indicating that acupuncture can help to relieve MS-induced depression.</p>
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<p><b>Objective</b>To investigate the effects of cynomorium songaricum (CS) decoction on the testis weight, serum testosterone level, and sperm parameters of rats with oligoasthenospermia (OAS), explore its action mechanism of improving the proliferation of undifferentiated spermatogonial cells, and provide some experimental and theoretical evidence for the development of new Chinese drugs for OAS.</p><p><b>METHODS</b>Thirty 8-week-old male SD rats were randomly divided into five groups of equal number: blank control, model control, high-dose CS, medium-dose CS, and low-dose CS. OAS models were established by intraperitoneal injection of cyclophosphamide and, a month later, treated intragastrically with normal saline or CS at 2, 1, and 0.5 g per kg of the body weight per day, all for 4 weeks. Then, the testes of the animals were harvested to obtain the testicular weight, sperm concentration and motility, and the level of serum testosterone (T), detect the expressions of the transcription factor 1 (Oct4), Thy-1 cell surface antigen (Thy1), promyelocytic leukemia zinc finger (PLZF), KIT proto-oncogene receptor tyrosine kinase (C-kit) and glial cell-derived neurotrophic factor (GDNF) in the testis tissue of the rats in the low-dose CS group by real-time PCR.</p><p><b>RESULTS</b>The testis weights in the blank control, model control, high-dose CS, medium-dose CS, and low-dose CS groups were (1.52±0.06), (1.55±0.06), (1.43±0.30), (1.35±0.40) and (1.34±0.04) g, respectively, not significantly different in the blank and model controls from those in the CS groups (P>0.05). The visual field sperm count per 10 HP was significantly increased in the high-, medium-, and low-dose CS groups (202±20, 196±5 and 216±25) as compared with the blank and model controls (200±15 and 134±30) (P<0.05). The mRNA expressions of the Oct4, Thy1, PLZF and GDNF genes were remarkably higher in the low-dose CS group than in the controls (P<0.05), but that of the C-kit gene showed no significant difference from the latter (P>0.05). The visual field sperm motility per 10 HP was markedly increased in the blank control (［52.1±5.5］%), model control (［38.1±2.5］%), high-dose CS (［59.1±9.5］%), medium-dose CS (［58.7±9.5］%), and low-dose CS (［49.6±1.0］%) groups, and so was the level of serum testosterone (［190±87.5］, ［82.5±25.8］, ［229±75.6］, ［331±86.7］ and ［185±82.4］ mmol/L), both remarkably higher in the CS groups than in the model controls (P<0.05) but with no statistically significant difference between the CS groups and the blank controls (P>0.05).</p><p><b>CONCLUSIONS</b>CS can significantly improve sperm concentration, sperm motility and serum T level in OAS rats, probably by inducing the expression of GDNF in the rat Sertoli cells, promoting the proliferation of undifferentiated spermatogonial cells, and enhancing spermatogenesis.</p>
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Bone marrow mesenchymal stem cells (BMSCs) have been shown to be multipotent cells that possess high self-replicating capacity.The purpose of our study was to investigate the feasibility of using enteric neuron-like cells obtained by in vitro induction and differentiated from rat BMSCs for the treatment of Hirschsprung's disease (HD).Glial cell-derived neurotrophic factor (GDNF) and neurotrophin-3 (NT-3) are neurotrophic factors that play important roles in neuronal development,differentiation,survival and function.Meanwhile,GDNF mutations are a major cause of HD.In this study,BMSCs were transfected with eukaryotic expression plasmids co-expressing GDNF and NT-3,and the transfected cells displayed neuron-like changes after differentiation induced by fetal gut culture medium (FGCM).Immunofluorescence assay showed positive expression of the neuronal marker NSE and the enteric neuronal markers PGP9.5,VIP and nNOS.Reverse transcription-polymerase chain reaction (RT-PCR) revealed the expression of GDNF and NT-3 in transfected BMSCs.The present study indicates that genetically modified BMSCs co-expressing GDNF and NT-3 are able to differentiate into enteric neuronal cells and express enteric nerve markers when induced by FGCM.This study provides an experimental basis for gene therapy to treat enteric nervous system-related disorders,such as HD.
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Objective To explore the effects of constraint-induced movement therapy (CIMT) on the expression of tyrosine hydroxylase (TH) and glial cell derived neurotrophic factor (GDNF) in Parkinson's disease (PD) model rats. MethodsPD models were established by microinjection of 6-hydroxydopamine (6-OHDA) solution into substantia nigra of rats' right cerebral hemisphere.Forty-two model rats were divided randomly into an exercise group and a control group 1 week after microinjection.The exercise group rats were forced to use their impaired limbs by placing their nonimpaired fore-limbs in casts.The control group rats were housed in the same environment without any special treatment.Two weeks after 6-OHDA infusion and exercise training,the behavioral changes of rats were examined after intraperitoneal injection apomorphine ( APO).The content of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) was measured by high performance liquid chromatography with electrochemistry ( HPLAEC) ; the expressions of TH and GDNF in striatum were detected by immunohistochemical methods and TH,GDNF mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR).Results After 2 weeks of training,the rotating laps of the rats in exercise group within 30 min after APO induction,reduced to a significantly greater extent when compared to the control group (P ＜ 0.05).The content of DA and it's metabolites DOPAC in striatum homogenate was significantly higher in exercise group than that in the control group ( P ＜ 0.05 ),and the expression levels,of TH and GDNF protein/ mRNA were also significantly higher in the exercise group than those in control group ( P ＜ 0.05 ).Conclusions CIMT can improve the behavioral performance of PD rats,probably through promoting the expressions of TH and GDNF protein/mRNA in striatum,and increasing DA and it's metabolites DOPAC level.