Study on MTA combined with fibronectin as pulp capping agent

AIM:This study was aimed to assess the effect of mineral trioxide aggregate (MTA) combined with fibronectin on reparative dentinogenesis and odontoblast differentiation, investigate the possible mechanism underlying traumatized pulp repair, which would facilitate the choosing of ideal pulp capping agents. METHODS:192 teeth from 16 adult cats were used. Class V cavties were prepared on the facial surface. The pulps of cats were exposed mechanically and then capped directly with MTA, MTA combined with fibronectin, calcium hydroxide, fibronectin and starch as control. The pulpal tissue reactions were assessed by light microscopy at healing interval of 1 and 4 weeks.RESULTS:1 week after pulp capping, no reparative dentin formation was observed in each group. 4 weeks after pulp capping, the dental pulps capped with MTA/fibronectin showed no or slight cellular inflammatory responses and odontoblast differentiation with tublar dentin bridge on the exposed sites. In MTA group, the dental pulps showed slight to moderate cellular inflammatory responses with osteodentin formation. In calcium hydroxide group, the pulps showed moderate to severe inflammatory responses with calcified matrix. In fibronectin and starch group, no dentin bridge formation was observed, the pulps showed severe cellular inflammatory responses.CONCLUSION:(1) MTA combined with fibronectin induced to form complete and tublar dentin bridge. In MTA group, most of the formed dentin bridge was irregular and osteodentin. (2) MTA combined with fibronectin is a bioactive pulp-capping agent and has a great worth in vital pulp therapy.     

Differentiation of embryonic-like stem cells derived from human bone marrow into multinucleated fibers in vitro

AIM: To compare the capacity of in vitro differentiation into multinucleated fibers between embryonic-like stem cells (ELSCs) and mesenchymal stem cells (MSCs) derived from human bone marrow. METHODS: To isolate ELSCs, human bone marrow mononuclear cells were cultured in gelatin-coated flask with serum-free Knockout-DMEM medium designed for the expansion of human embryonic stem cells. MSCs were isolated from the same bone marrow by the traditional method. The morphological characters of both ELSCs and MSCs were observed under inverted phase-contrast microscope, and the expression of their multipotent antigen markers was identified by immunofluorescent staining. ELSCs and MSCs were cultured in myogenic differentiation medium. The protein levels of muscle-specific antigen markers myosin heavy chain (MHC), myogenin and MyoD were detected by the method of immunostaining. The mRNA expression of MHC, myogenin and MyoD was detected by RT-PCR. The capacity of in vitro differentiation into multinucleated fibers was compared between ELSCs and MSCs by calculating the proportion of MHC-positive multinucleated fibers. RESULTS: ELSCs, which weakly expressed the multipotential markers Oct-4, Nanog-3 and Sox-2, were isolated from bone marrow by the method of serum-free medium. ELSCs appeared smaller, slenderer and more homogeneous, and were morphologically different from MSCs derived from the same marrow. No multipotential marker in MSCs was expressed. ELSCs and MSCs were induced into long multinucleated fibers expressing MHC and myogenin at mRNA and protein levels by culturing in the myogenic differentiation medium. However, on the 10th day after induction, the proportion of the MHC-positive fibers in ELSCs was (25.7?4.1)%, and the proportion in MSCs was (15.8?7.6)%.The capacity for differentiation into muscle in ELSCs was significantly higher than that in MSCs (P<0.05). CONCLUSION: Bone marrow ELSCs are induced into multinucleated fibers and have the stronger myogenic differentiation capacity than MSCs derived from the same marrow. ELSCs are a more ideal candidate for muscular disease therapy.     

Expression of neuronal nuclear antigen and neuron-specific enolase in developing human embryonic small intestines

AIM：To investigate the neuronal nuclear antigen (NeuN) and neuron-specific enolase (NSE) distribution in the developing stage of human embryonic small intestines and their clinical significance. METHODS：Sixteen cases of human embryos at 2~4 months of gestational age were used in the present study. The technique of immunohistochemical staining was used to detect the expression and distribution of NeuN and NSE in small intestinal walls. RESULTS：At 2~4 months of gestational age, NSE was strongly expressed in neurons and nerve fibers of the small intestinal myenteric nerve plexuses in human embryos. The numbers of NSE-positive cells and fibers gradually increased in the small intestinal submucosa with the increase in gestational age, and a few NSE-positive cells located in the small intestinal glands of human embryos. NeuN-positive cells scattered in the epithelium and glands of the small intestinal mucosa, and the number of NeuN-positive cells gradually increased with the increase in gestational age. But there were no NeuN-positive cells in the small intestinal submucosa. CONCLUSION: The expression and distribution of NeuN are not consistent with those of NSE during the development of human embryonic small intestines, and both of them may be involved in the development of neurons and neuroendocrine cells in small intestinal walls.     

Up-regulatory effect of nerve growth factor on substance P in the experimental asthma

AIM: To explore the regulatory mechanism of nerve growth factor (NGF) on substance P in the experimental asthmatic guinea pig. METHODS: Radioimmunoassay was used to determine the alteration of substance P levels in the lower respiratory tract and visceral sensory afferent sites while NGF was absent (inhalation of NGF antibody through nasal cavity) in the asthmatic guinea pig. RESULTS: The contents of substance P in the trachea, bronchus, lung, C7-T5 spinal ganglia and the correspondent spinal dorsal horn, nodose ganglia and solitary nucleus area in the experimental asthmatic guinea pig with the absent of NGF in the respiratory tract, were much lower than those in the asthmatic and control groups (P<0.01). CONCLUSION: NGF upregulates the contents of substance P in the lower respiratory tract and visceral sensory sites of the experimental asthmatic guinea pig, which might be involved in the pathogenesis of asthma.     

Effects of CSF-1,IL-1α on CSF-1 receptor gene expression in rat dental follicle cells

AIM: To study the effects of colony stimulating factor(CSF-1) and IL-1α on CSF-1 receptor mRNA levels and to determine if the autocrine effect is inhibited through the CSF-1 receptor.METHODS: Rat dental follicle cells were cultured in vitro.The effects of different concentrations of CSF-1 and IL-1α on CSF-1 receptor gene expression were detected by means of RT-PCR.RESULTS: High concentrations of CSF-1 reduced the gene expression of the CSF-1 receptor. IL-1α had no effects on CSF-1 receptor mRNA levels.CONCLUSION: High concentrations of CSF-1 inhibit the expression of CSF-1 receptor.IL-1α has no effect on the expression of CSF-1 receptor mRNA.     

The effects of ciliary neurotrophic factor on rat sciatic nerve regeneration

AIM: To observe the effects of ciliary neurotrophic factor (CNTF) on rat sciatic nerve regeneration, and compare the similarities and differences of its effects with that of nerve growth factor (NGF). METHODS: Sciatic nerve impairment model was prepared by break-restoring rat sciatic nerve. After intramuscular injection of different doses of CNTF at the damaged nerve for 45 days, the latent period and conduction velocity of action potential were determined. RESULTS: Compared with model group, the latent periods of all the CNTF treatment groups were significantly shortened (P<0.01) and the conduction velocity became faster significantly (P<0.01). Additionally, the effect on latent period in middle and high CNTF dosage groups is not significantly different form that in NGF treatment group (P>0.05). However, the conduction velocity in CNTF high dosage group is significantly faster than that in NGF treatment group (P<0.01). CONCLUSION: The effect of CNTF on promoting the rat sciatic nerve regeneration is better than that of NGF.     

Effects of exercise combined with forsamax on bone mineral density and nerve conduction in ovariectomy-induced osteoporosis rats

AIM: To observe the effects of exercise (EX) and forsamax (FOX) on bone mineral density (BMD) and nerve conduction in ovariectomized rats, and to determine whether exercise can enhance the effects of forsamax on postmenopausal osteoporosis (PMOP). METHODS: Ninety 6-month-old female SD rats were randomly divided into 2 groups: sham group (18 rats) and ovariectomized group (72 rats). Eight weeks after ovariectomy, dual-energy X-ray absorptiometry was applied to scan the BMD of the fourth lumbar vertebra. The level of serum estradiol (E₂) was analyzed by ELISA. The living ovariectomized rats were then divided into 4 groups: ovariectomized model group (OVX), fosamax treatment group (OVX+FOX), exercise treatment group (OVX+EX), and exercise combined with fosamax treatment group (OVX+FOX+EX). After treated with fosamax (1 mg/kg intragastrically) and/or exercise for 12 weeks, the BMD of the fourth lumbar vertebra, the motor nerve conduction velocity (MCV), motor distal latency (ML) and compound muscle action potential (CMAP) of the left femoral nerve were detected. The levels of serum type 1 procollagen carboxy-terminal propeptide (PICP) and type I collagen carboxy-terminal cross-linked telopeptide (ICTP) were also analyzed by ELISA. RESULTS: Twelve weeks after FOX and/or EX treatment, ovariectomized rats showed obviously lower BMD, higher PICP and ICTP than those in sham group (P<0.05). FOX or EX significantly increased BMD and reduced PICP induced by ovariectomy (P<0.05). FOX significantly reduced ICTP (P<0.05), but no remarkable difference was observed in OVX+FOX group as compared with OVX group. EX+FOX significantly increased BMD and reduced PICP and ICTP compared with FOX or EX alone (P<0.05). However, no obvious difference was observed between OVX+FOX group and OVX+EX group. No distinct difference in MCV and CMAP among the 5 groups was found. Neither ovariectomy nor FOX significantly affected ML. EX or EX+FOX made ML shorter than that in OVX group (fP<0.05), and ML was remarkably shortened in OVX+FOX+EX group than that in FOX alone group on the left femoral nerve (P<0.05). No significant difference between FOX and EX in the protective effects against ovariectomized rats was observed. CONCLUSION: Exercise and fosamax may restrain bone absorption effect of osteoclast and then improve the bone mineral density in ovariectomized rats.     

Upregulation of neurokinin A levels by nerve growth factor in the experimental asthmatic guinea pig

AIM: To explore the regulatory mechanism of nerve growth factor (NGF) on neurokinin A in the experimental asthmatic guinea pig. METHODS: Radioimmunoassay was used to determine the alteration of neurokinin A levels in the lower respiratory tract and visceral sensory afferent sites while NGF was absent (inhalation of NGF antibody through nasal cavity) in the asthmatic guinea pig. RESULTS: The contents of neurokinin A in the trachea, bronchus, lung, C₇-T₅ spinal ganglia and the correspondent spinal dorsal horn, nodose ganglia and solitary nucleus area in the experimental asthmatic guinea pig with the absent of NGF in the respiratory tract were much lower than those in the asthmatic and control groups (P＜0.01). CONCLUSION: NGF upregulated the contents of neurokinin A in the lower respiratory tract and visceral sensory sites of the experimental asthmatic guinea pig, and both might be involved in the pathogenesis of asthma.     

Effects of bFGF on brain edema,nerve function injury and autophagy related protein in rats with traumatic brain injury

AIM:To study the effects of basic fibroblast growth factor (bFGF) on brain edema, nerve function damage and autophagy related proteins in rats with head injury. METHODS:The rat model of craniocerebral injury (CI) was constructed. The rats were divided into control group, CI group, and low-, middle-and high-dose bFGF groups (n=10). The CI model was established in CI group, while the rats in control group were not given epidural impact. The rats in low-dose, middle-dose and high-dose bFGF groups were given bFGF at 2, 4 and 6 μg, respectively, by intraperitoneal injection after 30 min. The neurological function in the rats was evaluated by improved neurological function scoring. The rat brain tissues were taken, and the water content was detected. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1β in the brain tissue were measured by ELISA. The malondialdehyde (MDA) content was analyzed by thiobarbituric acid method. The activity of superoxide dismutase (SOD) was examined by WST-8 assay. The glutathine peroxidase (GSH-Px) activity was detected by colorimetric method. The protein levels of autophagy related proteins LC3-Ⅱ and beclin-1 in the brain tissues were determined by Western blot. RESULTS:The neurological function score was increased significantly of the rats in CI group. The rat model of craniocerebral injury was successfully constructed. Neurological function scores in the rats in low-dose, middle-dose and high-dose bFGF groups were reduced, the water content of the brain tissue was also reduced (P<0.05). The levels of TNF-α, IL-6 and IL-1 β were decreased in the brain tissues (P<0.05), the content of MDA was declined (P<0.05), the activities of SOD and GSH-Px were increased (P<0.05), the protein levels of LC3-Ⅱ and beclin-1 were decreased, compared with the untreated rats in CI group (P<0.05). CONCLUSION:bFGF improves the nerve function of the rats with craniocerebral injury, reduces the water content of the brain tissue, reduces the expression of autophagic protein LC3-Ⅱ and beclin-1.The mechanism is related to the inhibition of inflammatory reaction and oxidative damage.     

Protective effect of paeoniflorin on nerve cells in APP/PS1 mice and its mechanism

AIM: To investigate the therapeutic and preventive effects of paeoniflorin (PF) on APP/PS1 mice, and to explore the possible mechanism. METHODS: Fifteen male 5-month-old APP/PS1 non-dominant mice were chosen as normal control group, 15 male 5-month-old APP/PS1 double transgenic mice were used as model group, and 15 male 5-month-old APP/PS1 double transgenic mice treated with 5 mg/kg PF by intraperitoneal injection were allocated in administation group. The learning and memory ability of the mice in each group was detected by Morris water maze. The apoptosis was assessed by TUNEL fluorescence staining. The protein expression of PI3K, Akt, p-PI3K, p-Akt, caspase-3, caspase-9, Bcl-2 and Bax in cerebral cortex and hippocampus was detected by Western Blot. The protein expression levels and distribution of caspase-3 and caspase-9 were detected by immunohistochemistry. RESULTS: (1) Compared with normal control group, the learning and memory ability declined in APP/PS1 model group. Compared with APP/PS1 model group, PF obviously improve the ability of learning and memory in mice. (2) Compared with normal control group, the apoptosis of nerve cells in APP/PS1 model group significantly increased and distributed in wider areas, while that in PF group was reduced (P<0.05). (3) Compared with APP/PS1 model group, PF could significantly lower pro-apoptotic factors, caspase-3, caspase-9 and Bax (P<0.05), and increase the expression of anti-apoptotic factors, p-PI3K, p-Akt and Bcl-2 (P<0.05). CONCLUSION: PF can up-regulate the expression of Bcl-2 and down-regulate the expression levels of caspase-9, caspase-3 and Bax via the activation of PI3K/Akt pathway, thereby inhibiting the nerve cell apoptosis and protecting the nerve cells, so as to treat neurodegenerative diseases.     

豆制品行业废弃物转化生物有机肥的探索性研究

以清美公司豆制品生产中的废弃物豆渣和经过预处理的黄浆水污泥为原料,探索性研究2种调理剂以及堆体不同碳氮比对豆渣黄浆水污泥共堆肥发酵的影响。依据植物发芽率来确定调理剂添加量及碳氮比;测定分析堆肥发酵过程中温度、时间的变化趋势,并进行堆肥成品肥效检测。研究结果表明:豆渣与黄浆水污泥共堆肥的发酵最佳工艺为:调理剂选用秸秆粉,投加量为15 kg,C/N=25∶1。3#堆体发酵过程中高温温度(>50℃)可持续5 d以上,浸提液发芽率96.6%。堆肥成品肥效检测结果符合国家标准,可作施用于植物的中等肥料。     

Effect of human β-NGF gene-modified bone marrow-derived mesenchymal stem cells on rotational behavior of rats with Parkinson disease

AIM：To investigate the effect of human β-nerve growth factor (β-NGF) gene-modified bone marrow-derived mesenchymal stem cells (MSCs) transplantation on the rotational behavior improvement in a rat model of Parkinson disease (PD). METHODS：The rat model of PD was established successfully and the animals were divided into 4 groups:β-NGF-MSCs group (transplanted with 5×105 β-NGF-engineered MSCs), MSCs group (transplanted with 5×105 MSCs), DMEM/F12 group (5 μL transplantation medium was injected in the right striatum of the rats) and PD model group (without transplantation). The rotational scores were assessed 2 weeks, 4 weeks and 6 weeks after transplantation. At different time points after transplantation, the rats were tested for apomorphine (APO)-induced rotational behavior and the brains of the PD model rats were examined by fluorescence microscopy and immunohistochemical staining. RESULTS：Transplantation of human β-NGF gene-modified MSCs effectively improved the behavioral performance in the rats. At the 2nd, 4th and 6th weeks after cell transplantation, the rotational frequencies after injection of APO decreased significantly in β-NGF-MSCs group compared with MSCs group and PD group (P<0.05). Both β-NGF gene-modified MSCs and MSCs survived in the brains of PD model rats, had good compatibility with the host cells, and showed no signs of destroying the host and the glial cicatrisation. The β-NGF gene-modified MSCs expressed β-NGF stablely in the brains of PD model rats, and showed obvious improvement of the rotational behavior in the PD model rats induced by APO compared with MSCs group. CONCLUSION:The behavior of the rats with PD is significantly improved by transplanting β-NGF-modified MSCs in right striatum, and β-NGF gene therapy has potential clinical value．     

Effect of electroacupuncture on microglia phenotype in injured abducens nerve

AIM: To investigate the effect of electroacupuncture treatment on microglia phenotype in Beagle dogs with abducens nerve injury. METHODS: Healthy adult Beagle dogs were randomly divided into 4 groups:normal control group, sham operation group, injury group and electroacupuncture treatment group, with 5 dogs in each group. In sham operation group, only the isolated nerves were exposed. In injury group, the dogs were restrained when electroacupuncture was performed in electroacupuncture treatment group. In electroacupuncture treatment group, electroacupuncture was performed on the base of dog nerve injury. The experiment was continued for 2 weeks. Western blot was used to detect the expression levels of M1 and M2 markers in the microglia. RESULTS: The expression of inducible nitric oxide synthase (iNOS) in injury group was significantly higher than that in control group (P<0.05). In electroacupuncture treatment group, the expression of iNOS was significantly lower than that in injury group (P<0.05). The expression of interleukin-1β (IL-1β) in injury group and electroacupuncture treatment group was higher than that in control group and that in electroacupuncture treatment group was significantly lower than that in injury group (P<0.05). The expression of arginase in injury group and electroacupuncture treatment group was higher than that in control group (P<0.05), and that in electroacupuncture treatment group was higher than that in injury group (P<0.05). Meanwhile, the expression of brain-derived neurotrophic factor (BDNF) in injury group and electroacupuncture treatment group was increased compared with control group (P<0.05). But the expression of BDNF in electroacupuncture treatment group was higher than that in injury group (P<0.05).CONCLUSION: After abducens nerve injury, electroacupuncture treatment reduces the expression levels of M1 marker proteins in microglia and increases the expression levels of M2 marker proteins.     

‘长富2号’苹果果实类黄酮组成和含量研究

采用反相高效液相色谱法对‘长富2号’苹果果皮和果肉中的类黄酮进行了测定,并对6个产地‘长富2号’苹果的类黄酮组成与含量进行了比较研究。结果表明:果皮含4类16种类黄酮,总含量810.12～1304.59mg·kg-(1黄酮醇占58.3%～73.1%);果肉含3类11种类黄酮,总含量79.87～124.88mg·kg-1(黄烷醇占67.5%～85.5%);果肉中各种类黄酮含量均很低,特别是黄酮醇,含量仅为果皮的0.1%～3.1%;6个产地‘长富2号’苹果所含类黄酮种类完全相同,产地间果皮黄酮醇液相色谱指纹图谱相似度高达0.922～0.990;不同产地间类黄酮含量多有明显差异(P0.05),陕西白水样品果皮中类黄酮含量最高而果肉中最低,河北昌黎样品果皮类黄酮含量最低,山东牟平样品果肉类黄酮含量最高;平均单果含类黄酮35.14mg,其中,果皮类黄酮占41.3%,果肉类黄酮占58.7%。     

The effect of human complement C5b~9 complex on nitric oxide synthesis in glomerular mesangial cells of rats

AIM:To study the effect of human complement C_5b~9 complex on nitric oxide(NO) synthesis of glomerular mesangial cells (MC). METHODS: First, the human complement C_5b~9 complexes were isolated and glomerular MC of rats were cultured. Second, the MC were stimulated with C_5b~9 complex and changes of metabolism products of NO(NO₃^- and NO₂) in MC culture supernatant at 6,24 and 48 hours after C₊5b~9 stimulating were detected. Moreover, cGMP levels in cultured MC were also measured. RESULTS: NO₃^-／NO₂^- contents from culture supernatant and cGMP levels in MC were increased parallelly after C_5b~9 complex stimulation. Further, NO synthesis was inhibited by L-N^G-nitro-arginine-methylester(L-NAME). CONCLUSION: NO synthesis of rat glomerular MC was incerased by human complement C_5b~9 stimulation.     

Study on the immunological function of sodium butyrate-induced immature human monocyte-derived dendritic cells

AIM: To investigate the immunological function of sodium butyrate-induced immature dendritic cells in vitro.METHODS: The human monocyte-derived dendritic cells were induced in the presence of human granulocyte macrophage-colony stimulating factor(GM-CSF) and interleukin-4 (IL-4), combined with sodium butyrate. The immunological function of sodium butyrate-induced dendritic cells was detected by the FCM, endocytic activity, T cells stimulatory proliferation capacity, and interleukin-12 (IL-12) production.RESULTS: Sodium butyrate could down-regulate the major histocompatibility complex(MHC) class II and costimulatory molecules of dendritic cells, increase the endocytic activity, induce a stage of T-cell anergey, and inhibit the T helper cell type 1-skewing factor IL-12 production. CONCLUSION: Sodium butyrate inhibits the maturation of dendritic cells and induces production of immature dendritic cells, which may help to explore the machenism of its epigenitic modification.     

Mechanisms of nitric oxide synthesis induced by human complement C5b-9complex in glomerular mesangial cells of rats

AIM: To explore the mechanism of the nitric oxide (NO) synthesis induced by human C5b-9 complex in glomerular mesangial cells(MC) of rats. METHODS: The MC of rats were cultured and stimulated with human complement C5b-9 complex to induce TNFα and IL-1β. At the same time, several parameters related to NO synthesis were measured at 3 h, 6 h and 24 h after C5b-9 stimulation. The effects of monoclonal antibodies against TNFα and IL-1β on NO synthesis were examined in this system. RESULTS: TNFα concentration in supernatant from MC in C5b-9 group was higher than that of control group at 6, 24 h after stimulation with C5b-9 complex and reversed by adding anti-TNFα McAb. C5b-9 complex didn't stimulate the release of IL-1β in same system. In addition, the expression of iNOS mRNA in MC was observed at 3 h after stimulation with C5b-9. Levels of iNOS mRNA expression and cGMP in MC and NO₃^-/NO₂^- in supernatant from MC in C5b-9 group were higher than those in control group at 6, 24 h after C5b-9 stimulation, these changes were also reversed by adding monoclonal antibody against TNFα. CONCLUSION: C5b-9 complex could induce iNOS mRNA expression at 3 h after C5b-9 stimulation, and the synthesis of NO at 6, 24 h was related to TNFα released from cultured MC of rats by C5b-9 complex to a certain extent.     

Study on polarized Th1/Th2 cell in vitro from adult human peripheral blood

AIM: To investigate the details of CD4⁺ T cell polarized to Th1/Th2 in vitro. METHODS: After isolated the PBMCs and blood-plasma from adult human peripheral blood by Ficoll-Hypaque centrifugation, the PBMC culture procedure with or without the self-blood -plasma was applied to polarize T cells in vitro, these cells were polarized by PHA(20 mg/L),non-PHA respectively. The polarized rates of Th cell after 24 h,48 h,72 h were estimated respectively by flow cytometry following two-color immunofluorescent staining. RESULTS: CD4⁺T cell would polarize to Th1/Th2 two subsets after self-cytokines and PHA activation in vitro. The polarized rates of T cell after cultured for 24 h,48 h and 72 h were (13.28%±1.59%)/(12.70%±1.65%),(17.19%±1.03%)/(17.50%±1.30%),(19.49%±2.87%)/(18.58%±1.49%) respectively, but the polarized rates of T cell were very low if without self-blood-plasma. The difference between them was significant. The ratios of Th1/Th2 cells were about 1. CONCLUSION: CD4⁺T cell from adult human peripheral blood would polarize to Th1/Th2 two subsets in the presence of self-blood-plasma and PHA(20 mg/L) in vitro, and the cell number of Th1 and Th2 would be in balance.     

Influence of 8-week swimming on peripheral neuropathy in type 2 diabetic rats

AIM: To explore the influence of long-term swimming on peripheral neuropathy in type 2 diabetic rats. METHODS: Male Wistar rats were fed with a high-fat and high-fructose diet, and injected with streptozocin to establish a model of type 2 diabetes mellitus. The rats were randomly divided into 4 groups: blank control group (C group), exercise control group (CE group), diabetes mellitus group (DM group) and diabetes mellitus+exercise group (DME group). The rats in CE group and DME group received 8-week swimming training (6 d/week). The training time was 20, 30 and 45 min in the first 3 d,respectively, and then it increased to 60 min a day. Eight weeks later, the motor nerve conduction velocity (MNCV) and the levels of tumor necrosis factor α (TNF-α), interleukin 6 (IL-6) and C-reactive protein (CRP) in sciatic nerve tissues of the rats were measured. The morphological changes of the sciatic nerve were also observed under light microscope. RESULTS: Compared with DM group, 8-week swimming obviously accelerated the MNCV (P<0.05), decreased the levels of TNF-α, IL-6 and CRP in DME group (but no significant difference, P>0.05). The obvious nerve injury in DM group was observed. However, the pathological change of the sciatic nerve in DME group was relieved. CONCLUSION: Eight-week swimming training significantly accelerates the MNCV, attenuates the nerve injury in diabetic rats and has protective effect on peripheral nerve, which may be correlated with relieving the inflammatory reaction.