[Mechanisms of moxibustion preconditioning underlying improving learning-memory ability by regulating polarization of microglia via TLR4/NF-κB signaling pathway in AD rats].

OBJECTIVE: To observe the effect of moxibustion preconditioning on learning-memory ability, Toll like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB) signal pathway related proteins and microglia in rats with Alzheimer's disease (AD), so as to explore its possible mechanisms underlying improvement of AD. METHODS: Male SD rats were randomly divided into normal, sham operation, AD model and pre-moxibustion groups, with 9 rats in each group. Moxibustion was applied to "Baihui"(GV20), "Shenshu"(BL23) and "Zusanli"(ST36) for 15 min, once daily, 6 days as a course of treatment for 3 courses. At the end of moxibustion, the AD model was established by injection of Aß25-35 aggregation solution into the bilateral hippocampus. The sham operation group was only injected with the same amount of 0.9% Nacl solution. The spatial learning-memory ability of rats was detected by Morris water maze test, the ultrastructure of hippocampal neurons was observed by transmission electron microscope (TEM). The histopathological changes of hippocampus tissue were observed by HE staining, and the protein expression levels of TLR4 and NF-κB p65 in the hippocampus detected by Western blot, and the positive expressions of Iba-1, CD80 and CD206 in the hippocampal CA1 region were detected by immunofluorescence labeling. The contents of inflammatory factors IL-1ß, TNF-α and IL-10 in the hippocampus were measured by ELISA. RESULTS: Compared with the sham operation group, the escape latency was significantly increased (P<0.01), and the number of platform quadrant crossing times was decreased (P<0.01) in the model group. In comparison with the model group, the increased escape latency and the decreased platform quadrant crossing times were reversed in the pre-moxibustion group (P<0.01). TEM and light microscope observation showed loose arrangement of cells, enlarged cell space, degeneration, swelling and deformation of hippocampal neurons, rupture of membranes of a large number of cells, reduction of mitochondria, dilation of endoplasmic reticulum, and matrix vacuoles, uneven distribution of organelles and cytoplasm, and being difficult in distinguishing the nuclear cytoplasm in the model group, which was relatively milder in the pre-moxibustion group. The expression levels of hippocampal NF-κB p65 and TLR4, the mean immunofluorescence density of Iba-1 and CD80, as well as the contents of IL-1ß and TNF-α in hippocampal CA1 region were significantly increased in the model group than those in the sham operation group (P<0.01), and obviously decreased in the pre-moxibustion group than those in the model group (P<0.05, P<0.01). Whereas the expression of CD206 and the content of IL-10 were evidently decreased in the model group than those in the sham operation group (P<0.01), and strikingly increased in the pre-moxibustion group than those in the model group (P<0.01). No significant differences were found between the sham operation group and the normal group in all the indexes mention above (P>0.05). CONCLUSION: Pre-moxibustion at GV20, BL23 and ST36 can improve learning-memory ability in AD rats, which may be associated with its functions in promoting the polarization of microglia from M1 to M2 and reducing the neuroinflammatory response by way of TLR4/NF-κB signaling pathway.

[Involvement of miR-126-3p via mTOR/HIF-1α signaling pathway in effect of electroacupuncture on angiogenesis in rats with cerebral ischemia].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on miRNA-126-3p and mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) signaling pathway in rats with cerebral ischemia (CI), so as to explore the underlying mechanism of EA on angiogenesis. METHODS: Male SD rats were randomly divided into control group, model group, EA group and EA+inhibitor group (inhibitor group), which were further divided into 3, 7 and 14 d subgroups, with 12 rats in each sub-group. The CI model was established by occlusion of the middle cerebral artery. EA (2 Hz/20 Hz, 0.5 mA) was applied to "Dazhui" (GV14), "Baihui" (GV20) for 20 min, once daily for 14 days at most. Rats of the inhibitor group were given an intraperitoneally injection of mTOR inhibitor (0.1 mg/mL, 0.3 mg/kg) before daily EA. The neurological function was evaluated by modified neurological severity score (mNSS). The ultrastructure of cortical neurons and microvascular endothelial cells in ischemic penumbra was observed by transmission electron microscope, and the microvessel density (MVD) of cortical endothelium in ischemic penumbra was detected by immunohistochemistry. Western blot and quantitative real-time PCR were used to detect the protein and mRNA expression of mTOR, HIF-1α and the expression of miR-126-3p in the cortex of ischemic penumbra, respectively. RESULTS: After modeling, compared with the control group at the same time point, the mNSS of the model group was increased (P<0.01), and decreased over time (P<0.01). The cortical neurons and brain microvascular endothelial cells in the ischemic penumbra were edema, and the cell structure was damaged obviously in the model group.The MVD value and the expressions of mTOR、HIF-1α proteins and mRNAs were increased (P<0.01), while the expression of miR-126-3p decreased (P<0.01) in the model group relative to the control group. Compared with the model group at the same time point, the mNSS of both intervention groups was significantly reduced (P<0.01, P<0.05), the neuron and cerebral microvascular structure improved to varying degrees, and the MVD value, the expressions of mTOR and HIF-1α protein and mRNA, and the expression of miR-126-3p of the two treatment groups were increased (P<0.01, P<0.05) at all time points (excep MVD at day 7 in the inhibitor group). Compared with the EA group at the same time point, MVD, the expressions of mTOR, HIF-1α proteins and mRNAs and miR-126-3p in the inhibitor group were all decreased (P<0.05,P<0.01). Compared with the group itself at 4 hours after modeling and day 3 and day 7, the mNSS was decreased at day 14 （P<0.01） in the model, EA and inhibitor groups. Compared with the group itself at day 3, the MVD value and the expression of mTOR protein were increased at day 7 and day 14 in the model, EA and inhibitor groups (P<0.01, P<0.05). Compared with the group itself at day 3 and day 7, the expression of mTOR mRNA and miR-126-3p were up-regulated at day 14 in the model and EA groups (P<0.01, P<0.05).Compared with the group itself at day 3, the mRNA expressions of mTOR and HIF-1α were increased at day 7 and day 14 (P<0.01, P<0.05) in the inhibitor group. CONCLUSION: EA at GV14 and GV20 can alleviate neurological deficit and improve angiogenesis in rats with CI, which may be related with its effect in up-regulating the expression of mTOR and HIF-1α, improving activation of miR-126-3p in the cortex of ischemic penumbra.

[Effects of pre-moxibustion on expression of phosphorylated Tau protein and related protein kinases in hippocampal CA3 region of AD rats].

OBJECTIVE: To observe the effect of pre-moxibustion at "Baihui"(GV20), "Shenshu"(BL23) and "Zusanli"(ST36) on expression of Tau protein and related protein kinases as glycogen synthase kinase-3ß (GSK-3ß), etc. in the hippocampal CA3 region of Alzheimer's disease (AD) rats, so as to explore its mechanism underlying prevention and treatment of AD cognitive impairment. METHODS: Male SD rats were randomly divided into 4 groups: normal control, sham operation， model and pre-moxibustion，with 9 rats in each group. Rats of the pre-moxibustion group received moxibustion of GV20, BL23 and ST36 for 15 min, once a day, 6 days a week for 3 weeks. After completion of moxibustion, the AD model was reproduced by injection of amyloid beta-peptide 25-35(Aß 25-35) aggregation solution 1 µL (5 µg/µL) into the bilateral hippocampus, rats of the sham operation group received injection of the same dose of normal saline into the hippocampus. The spatial learning-memory ability was detected using Morris water maze test, and changes of the ultrastructure of hippocampal neurons were observed using electron microscope, and those of histopathological changes of hippocampus tissue observed using hematoxylin eosin (H.E.) staining. The expression levels of hippocampal GSK-3ß, p-Tau, CDK5 and Synapsin I proteins were detected by Western blot and immunohistochemistry, respectively. RESULTS: No significances were found between the normal control and sham groups in all the indexes (P>0.05). Compared with the control group, the escape latency of place navigation test of Morris water maze test, expression of GSK-3ß and CDK5 and the immunoactivity of GSK-3ß, CDK5 and p-Tau were significantly increased (P<0.01), and the residence time in the platform quadrant and the number of platform crossing of spatial prob test and the expression of Synapsin Ⅰ significantly reduced in the model group (P<0.01). Following the intervention, the increase of escape latency, expression of GSK-3ß and CDK5 and the immunoactivity of GSK-3ß, CDK5 and p-Tau, and the decrease of residence time in the platform quadrant, number of platform crossing and the expression of Synapsin Ⅰ were reversed in the pre-moxibustion group (P<0.05, P<0.01). Outcomes of ultrastructure and histopathological observations respectively showed edema of hippocampal nerve cells at varying degrees, moderate edema of the cytoplasma, chromatin condensation at the edge of the nucleus, partial mitochondrial vacuole-like degeneration, fracture of tubular crest, edema and expansion of Golgi body, disappearance of polarity, fracture of the rough endoplasmic reticulum, degeneration of ribosome and partial myelin axon and reduced synaptic vesicles in the presynaptic capsule; and reduced number of neurons with shrank body, disappearance of nucleolus and blurred nuclear boundary and vacuole-like degeneration in some of them in the model group, which were relatively milder in the pre-moxibustion group. CONCLUSION: Pre-moxibustion at GV20, BL23 and ST36 plays a role in slowing down the occurrence and development of cognitive impairment in AD rats, which may be related to its functions in inhibiting tau protein hyperphosphorylation and reducing the expression of some related protein kinases in the hippocampus.

Knockdown of asporin affects transforming growth factor-ß1-induced matrix synthesis in human intervertebral annulus cells.

BACKGROUND/OBJECTIVE: Asporin is associated with osteoarthritis and lumbar disk degeneration. Previous studies in chondrocytes showed that asporin can bind to transforming growth factor-ß1 (TGF-ß1) and downregulate matrix biosynthesis. However, this has not been studied in intervertebral disk (IVD) cells. This study aimed to inspect the expression of asporin under TGF-ß1 stimulation and its effect on TGF-ß1-induced matrix biosynthesis in human intervertebral annulus cells. METHODS: Human intervertebral annulus cells were obtained from the pathological region of IVD in eight patients. After primary culture and redifferentiation in alginate beads, cells were reseeded and treated with different concentrations (5 ng/mL, 10 ng/mL, and 15 ng/mL) of TGF-ß1 for up to 24 hours. Total RNA extracted from the cells and those with asporin knockdown were subjected to real-time polymerase chain reaction analysis to examine the expression of asporin and extracellular matrix genes. RESULTS: TGF-ß1 stimulation induces asporin transcription significantly in a dose- and time-dependent manner. Knockdown of endogenous asporin leads to the upregulated expression of collagen II alpha 1 and aggrecan. CONCLUSION: Our results have verified a functional feedback loop between TGF-ß1 and asporin in human intervertebral annulus cells indicating that TGF-ß1-induced annulus matrix biosynthesis can be significantly upregulated by knockdown of asporin. Therefore, asporin could be a potential new therapeutic target and inhibition of asporin could be adopted to enhance the anabolic effect of TGF-ß1 in human intervertebral annulus cells in degenerative IVD diseases.

[Evaluation of safety and anesthetic effect for ultrasound-guided cervical plexus block].

OBJECTIVE: To observe the influences upon the degree of diaphragmatic excursion during deep cervical plexus block at the third cervical vertebra (C3) and compare the safety and anesthetic effect of modified cervical plexus block by ultrasonic guidance and blocking of cervical plexus at one point. METHODS: Part I: 30 patients of ASA (American society of anesthesiologists) I-II scheduled for thyroid surgery were selected for bilateral cervical plexus block at C3 and bilateral skin nerve branches via ultrasonic guidance. Diaphragmatic excursion was recorded. Part II: 80 patients of ASAI-II scheduled for thyroid surgery were randomly divided into 2 groups: experimental group (Group U) and control group (Group C). In Group U, modified cervical plexus block was used to fix both sides of C3 and skin nerve branches. The anesthetic mixture with 2% lidocaine and 0.75% ropivacaine was injected. And anesthetic effects and complications were detected. In control group, traditional one-point method for blocking cervical plexus was employed. RESULTS: High-frequency Doppler sonography could clearly visualize important neck structures and precisely guide the injection of mixture to the transverse process of C3. Diaphragmatic excursion decreased significantly at 15 and 30 min post-blocking (P < 0.05). And no paralysis of diaphragmatic muscle occurred. Hoverer 3 cases had partial diaphragmatic paralysis. Both blood pressure and heart rate increased significantly post-blocking in both groups (P < 0.05 or 0.01). In comparison with Group C, the range of blood pressure was notably lower at 10 and 20 min in Group U. And heart rate was notably lower at 5, 10, 20 and 30 min (P < 0.05 or 0.01). Furthermore the onset time of skin nerve branches was significantly shorter in Group U (P < 0.01). And the anesthetic effect score was better than that in Group C (P < 0.01). The incidence of complications, such as hoarseness, was significantly lower in Group U (12 cases in Group C but none in Group U, P < 0.01) and Horner's syndrome (2 cases in Group C). The number of cases requiring hypotensor and heart rate control drug was significantly smaller in Group U than that in Group C (P < 0.01). CONCLUSION: The improving effect of ultrasound-guided cervical plexus block upon the degree of diaphragmatic movement is within the compensatory range of body. In comparison with the traditional one-point blocking of cervical plexus, the modified cervical plexus block with ultrasonic guidance offers better anesthetic effects, fewer complications and convenient anesthetic localization. Thus it may be clinically applicable.

Downregulation of protein kinase Cα was involved in selenite-induced apoptosis of NB4 cells.

We revealed in our previous research that sodium selenite induced obvious apoptosis of human leukemia NB4 cells, with reactive oxygen species (ROS), mitochondrial apoptosis pathway, and endoplasmic reticulum stress (ER stress) involved. In the present study, we revealed protein kinase Ca (PKCalpha) was dramatically downregulated in selenite-induced apoptosis, which was mediated by ROS. Besides, we confirmed PKCalpha played an antiapoptotic role through its effects on ERK1/2 and Akt, while its downregulation was attributed to caspase-3 and PP2Ac under the regulation of ROS. In summary, we speculated that in apoptosis of NB4 cells induced by selenite, PKCalpha functioned to counteract apoptosis, thus its downregulation seemed a mechanism aggravating apoptosis.