Long noncoding RNA MEG3 silencing protects against hypoxia-induced pheochromocytoma-12 cell injury through inhibition of TIMP2 promoter methylation.

Hypoxia is a common pathological process caused by insufficient oxygen. Long noncoding RNAs (lncRNAs) have been proven to participate in this pathology. Hypoxia is reported to significantly reduce the secretion of tissue inhibitor of metalloproteinase 2 (TIMP2) and TIMP2 induces pheochromocytoma-12 (PC12) cell cycle arrest. Thus, our study aimed to explore the mechanism by which lncRNA maternally expressed gene 3 (MEG3) was implicated in hypoxia-induced PC12 cell injury through TIMP2 promoter methylation. To elucidate the potential biological significance of MEG3 and the regulatory mechanism between MEG3 and TIMP2, a hypoxia-induced PC12 cell injury model was generated. The hypoxia-exposed cells were subjected to a series of overexpression plasmids and short hairpin RNAs, followed by the measurement of levels of MEG3, TIMP2, lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxygen species (ROS), Bcl-2-associated X protein, B-cell lymphoma-2, and caspase-3, as well as the changes in MMP, cell proliferation, apoptosis, and cell cycle progression. On the basis of the findings, MEG3 was upregulated in hypoxia-injured PC12 cells. MEG3 recruited methylation proteins DNMT3a, DNMT3b, and MBD1 and accelerated TIMP2 promoter methylation, which in turn inhibited its expression. Moreover, PC12 cells following MEG3 silencing and TIMP2 overexpression exhibited significantly decreased levels of LDH, MDA, and ROS along with cell apoptosis, yet increased SOD and MMP levels, as well as cell cycle entry to the S phase and cell proliferation. In conclusion, MEG3 silencing suppresses hypoxia-induced PC12 cell injury by inhibiting TIMP2 promoter methylation. This study may provide novel therapeutic targets for hypoxia-induced injury.

Nicotinic Acetylcholine Receptor Alpha7 Subunit Mediates Vagus Nerve Stimulation-Induced Neuroprotection in Acute Permanent Cerebral Ischemia by a7nAchR/JAK2 Pathway.

BACKGROUND The role of nicotinic acetylcholine receptor alpha7 subunit (a7nAchR) in the treatment of acute cerebral ischemia by VNS has not been thoroughly clarified to date. Therefore, this study aimed to investigate the specific role of a7nAchR and explore whether this process is involved in the mechanisms of VNS-induced neuroprotection in rats undergoing permanent middle cerebral artery occlusion (PMCAO) surgery. MATERIAL AND METHODS Rats received a7nAChR antagonist (A) or antagonist placebo injection for control (AC), followed by PMCAO and VNS treatment, whereas the a7nAChR agonist (P) was utilized singly without VNS treatment but only with PMCAO pretreatment. The rats were randomly divided into 6 groups: sham PMCAO, PMCAO, PMCAO+VNS, PMCAO+VNS+A, PMCAO+VNS+AC, and PMCAO+P. Neurological function and cerebral infarct volume were measured to evaluate the level of brain injury at 24 h after PMCAO or PMCAO-sham. Moreover, the related proteins levels of a7nAChR, p-JAK2, and p-STAT3 in the ischemic penumbra were assessed by Western blot analysis. RESULTS Rats pretreated with VNS had significantly improved neurological function and reduced cerebral infarct volume after PMCAO injury (p<0.05). In addition, VNS enhanced the levels of a7nAchR, p-JAK2, and p-STAT3 in the ischemic penumbra (p<0.05). However, inhibition of a7nAchR not only attenuated the beneficial neuroprotective effects induced by VNS, but also decreased levels of p-JAK2 and p-STAT3. Strikingly, pharmacological activation of a7nAchR can partially substitute for VNS-induced beneficial neurological protection. CONCLUSIONS These results suggest that a7nAchR is a pivotal mediator of VNS-induced neuroprotective effects on PMCAO injury, which may be related to suppressed inflammation via activation of the a7nAchR/JAK2 anti-inflammatory pathway.

[Surface electromyographic activities of submental muscles among stroke patients with dysphagia].

OBJECTIVE: To explore the swallowing functions of stroke patients with dysphagia. METHODS: A total of 41 subjects were recruited.There were 15 stroke patients with dysphagia, 12 stroke patients without swallowing disorders and 14 age-and gender-matched healthy controls.Surface electromyography (sEMG) was employed over the suprahyoid muscle group.Single swallow was applied twice with 5 and 10 ml of thin liquid barium as well as 5 and 10 ml of paste barium.The duration, average amplitude of sEMG and peak amplitude of submental muscle contraction were compared among three groups.Three-way analysis of variance (ANOVA) was performed. RESULTS: No significant differences existed in the general data among three groups (P > 0.05).However, all volumes, consistencies and durations [ (1.38 ± 0.21), (1.66 ± 0.30), (1.46 ± 0.24), (1.78 ± 0.28) s] were significantly longer for the group of dysphagia patients than for those without dysphagia and healthy subjects (P < 0.05).And the average amplitudes ( (16 ± 6), (15 ± 5), (20 ± 13), (19 ± 7) µV) were significantly smaller for the group of dysphagia patients than for those without dysphagia and healthy subjects (P < 0.05) while the peak amplitudes ((48 ± 23), (51 ± 23), (51 ± 31), (63 ± 32) µV) were significantly smaller for the group of dysphagia patients than for those without dysphagia and healthy subjects (P < 0.05). There were no significant differences between patients without dysphagia and those of healthy subjects (P > 0.05). CONCLUSION: As a simple and useful tool, sEMG is feasible for evaluating swallowing function and quantifying the strength of swallowing muscles in post-stroke patients with dysphagia.

Psychometric Properties of the Kessler 10 Scale in Chinese Parents of Children With Cancer.

BACKGROUND: The Kessler Psychological Distress Scale (K10) has been widely used in rating psychological distress in general and clinical populations. However, whether it can be used in parents of children with cancer is unknown. Still lacking is the evidence on its reliability and validity in culturally diverse groups. OBJECTIVE: The aim of this study was to translate the K10 into Mandarin Chinese and test its psychometric properties (especially the factor structure) of the Chinese version (C-K10) in parents of children with cancer. METHODS: By convenience sampling, 2 samples of parents of children with cancer (sample I, n = 206, and sample II, n = 103) were surveyed in Guangzhou, China. Sample I completed the C-K10, and the internal consistency reliability and exploratory factor analysis of the C-K10 were estimated. Sample II completed the C-K10, the State Subscale of State-Trait Anxiety Inventory, and the Zung Self-rating Depression Scale; confirmatory factor analysis and concurrent validity estimates were completed. RESULTS: The C-K10 demonstrated strong internal consistency reliability (Cronbach's α = .93). Both exploratory and confirmatory factor analyses supported a 2-factor structure (ie, anxiety and depression). The concurrent validity was moderate with Pearson correlations greater than 0.50 (P < .001). CONCLUSION: The C-K10 demonstrated very acceptable reliability and validity in screening psychological distress in Chinese parents of children with cancer. IMPLICATIONS FOR PRACTICE: This study provides evidence that the C-K10 is a valid tool that can be used in clinical settings to screen for psychological distress in Chinese parents of children with cancer.

[Effects of functional electrical stimulation on the improvement of motor function of patients with acute stroke: a randomized controlled trial].

OBJECTIVE: To investigate the effects of functional electrical stimulation (FES) on the improvement of motor and walking ability of the lower extremities of the patients with acute stroke. METHODS: Forty-six patients with stroke (including cerebral infarction and hemorrhage), aged 71 +/- 8 (45 - 84), hospitalized within 2 weeks (9 +/- 4 days) after the onset, matched with one another in the baseline measurements before treatment, were assigned randomly into 3 groups: FES group (n = 13), receiving standard rehabilitation combined with FES 30 minutes per day, 5 days per week for 3 weeks, placebo stimulation group (n = 15) receiving standard rehabilitation combined with the installment of the FES apparatus, operated in the same manner as mentioned above, however, without real electric stimulation, and control group (n = 13), receiving standard rehabilitation alone. The score of the composite spasticity scale (CSS) was measured, electromyography was conducted to measure the maximum isometric voluntary contraction (MIVC) of the ankle dorsi-flexors and plantar-flexors, and walking ability by the test of timed "Up and Go" before treatment, weekly during the 3-week treatment, and 8 weeks after the onset of stroke. RESULTS: After 3 weeks of treatment, the percentage of CSS score of the FES group was 31% +/- 35%, significantly lower than those of the placebo and control groups (50% +/- 88% and 65% +/- 65% respectively, both P < 0.05); the ankle dorsiflexion torque of MIVC of the FES group was 9 Nm +/- 5 Nm, significantly higher than those of the placebo and control groups (5 Nm +/- 3 Nm and 4 Nm +/- 5 Nm respectively, both P < 0.05), and the electromyogram co-contraction ratio of the FES group was 8% +/- 5%, significantly lower than those of the placebo and control groups (27% +/- 26% and 28% +/- 19% respectively, both P < 0.05). The time needed to recover the walking ability after the stroke onset of the FES group was 18 +/- 8 days, shorter by 2 approximately 3 days than those of the placebo and control groups (20 +/- 7 and 21 +/- 8 days respectively). The percentage of the patients able to walk with the help of a stick 3 weeks after treatment of the FES group was 85%, significantly higher than those of the placebo and control groups (60% and 46% respectively, both P < 0.05). 84.6% of the patients of the FES group returned home, a percentage significantly higher than those of the placebo and control groups (53% and 46% respectively, both P < 0.05). CONCLUSION: FES, plus standard rehabilitation, is effective in improving the motor and walking ability of the patients with acute stroke, to the degree that most patients are recovered to be able to return home.

Functional electrical stimulation increases neural stem/progenitor cell proliferation and neurogenesis in the subventricular zone of rats with stroke.

BACKGROUND: Functional electrical stimulation (FES) is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis. In this study, we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone (SVZ) after focal cerebral ischemia. METHODS: Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion (MCAO) were randomly assigned to the control group, the placebo stimulation group, and the FES group. The rats in each group were further assigned to one of four therapeutic periods (1, 3, 7, or 14 days). FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them. Two intraperitoneal injections of bromodeoxyuridine (BrdU) were given 4 hours apart every day beginning 48 hours after the MCAO. Neurogenesis was evaluated by immunofuorescence staining. Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells (NSCs) was investigated by Western blotting analysis. The data were subjected to one- way analysis of variance (ANOVA), followed by a Tukey/Kramer or Dunnett post hoc test. RESULTS: FES significantly increased the number of BrdU-positive cells and BrdU/glial fibrillary acidic protein double- positive neural progenitor cells in the SVZ on days 7 and 14 of the treatment (P < 0.05). The number of BrdU/doublecortin (DCX) double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group ((522.77 ± 33.32) cells/mm(2)) was significantly increased compared with the control group ((262.58 ± 35.11) cells/mm(2), P < 0.05) and the placebo group ((266.17 ± 47.98) cells/mm(2), P < 0.05). However, only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment. At day 7, Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving FES ((0.44 ± 0.05)%) compared with those of the control group rats ((0.31 ± 0.02)%, P < 0.05) or the placebo group rats ((0.31 ± 0.04)%, P < 0.05). At day 14, the corresponding values were (0.56 ± 0.05)% in the FES group compared with those of the control group rats ((0.50 ± 0.06)%, P < 0.05) or the placebo group rats ((0.48 ± 0.06)%, P < 0.05). CONCLUSION: FES augments the proliferation, differentiation, and migration of NSCs and thus promotes neurogenesis, which may be related to the improvement of neurological outcomes.

Effect of transcutaneous electrical nerve stimulation on symptomatic diabetic peripheral neuropathy: a meta-analysis of randomized controlled trials.

AIMS: To evaluate the effectiveness of transcutaneous electrical nerve stimulation (TENS) on diabetic peripheral neuropathy (DPN). METHODS: Randomized controlled trials (RCTs) comparing TENS with routine care, pharmacological interventions or placebo devices on patients with symptomatic DPN, were identified by electronic and manual searches. Studies were selected and available data were extracted independently by two investigators. Meta-analysis was performed by RevMan 4.2.8 software. RESULTS: Three RCTs involving 78 patients were included in this study. The reductions in mean pain score were significantly greater in TENS group than in placebo TENS group in 4 weeks and 6 weeks follow-up [4 weeks, SMD-5.37, 95% CI (-6.97, -3.77); 6 weeks, SMD-1.01, 95% CI (-2.01, -0.01)], but not in 12 weeks follow-up [SMD-1.65, 95% CI (-4.02, 0.73)]. TENS therapy was associated with significantly subjective improvement in overall neuropathic symptoms in 12 weeks follow-up [WMD-0.18, 95% CI (-0.32, -0.051)]. No TENS-related adverse events were registered in TENS group. CONCLUSIONS: TENS therapy may be an effective and safe strategy in treatment of symptomatic DPN. Due to small sample and short-term treatment duration, large multi-centre RCTs are needed to further evaluate the long-term effect of TENS on DPN.

[Effects of botulinum toxin guided by electric stimulation on spasticity in ankle plantar flexor of children with cerebral palsy: a randomized trial].

OBJECTIVE: To compare the effects of botulinum toxin A (BTX-A) injection guided by electric stimulation combined with physiotherapy, with physiotherapy only on the spasticity of the ankle plantar flexor in children with cerebral palsy (CP). METHODS: After signing the informed consent, 43 children with CP, aged 52.4 +/- 13.2 months (35 to 82 months), were randomly assigned into 2 groups, (1) BTX-A group (n = 23) treated with BTX-A injection guided by electric stimulation and (2) physiotherapy alone group (n = 20). Children in BTX-A group received injection of HengLi BTX-A in the ankle plantar flexors. A maximum dose of 12 units of BTX-A per kilogram body weight and maximumly 10 units of BTX-A per site were administered. Localization technique was the use of electrical stimulation guidance. Physiotherapy and ankle-foot orthosis were applied to children at 72 hours after injection in BTX-A group and at the time of being recruited into physiotherapy group. Ten days after entering into the study, the program was applied by the parents. Demographic data, including age, gender, number of the spastic lower limbs, affected side (left or right) were recorded. Clinical assessments included the range of passive movement (PROM) measured by goniometer while children maintained the knee extended, modified Ashworth scale (MAS), composite spasticity scale (CSS), D and E dimensions of the Gross Motor Function Measure (GMFM), and walking velocity (WV) was determined before treatment and at 2 weeks, 1, 2, and 3 months after treatment. RESULTS: No statistically significant differences were found in age, gender, number of the spastic lower limbs, affected side, as well as clinical assessments (PROM, MAS, CSS, GMFM and WV) before treatment between the 2 groups (P > 0.05). All the children showed a reduction of spasticity (PROM, MAS and CSS) after 2 weeks, 1, 2, and 3 months of treatment (P < 0.05). When compared with the baseline findings, the improvement of standing and walking (GMFM), walking velocity were statistically significant after 2 weeks, 1, 2, and 3 months of treatment (P < 0.05). Furthermore, the differences of PROM, MAS and CSS between the 2 groups at 2 weeks, 1, 2, and 3 months examination were also statistically significant (after 3 months of treatment: t(PROM) = 6.48, t(MAS) = 9.74, t(CSS) = 9.59; P < 0.05). The difference in GMFM between the 2 groups was statistically significant (t(1M) = 2.20, t(2M) = 3.26, t(3M) = 4.13; P < 0.05) at 1, 2, and 3 months after treatment. The difference of WV between the 2 groups was statistically significant (t(2M) = 2.12, t(3M) = 2.57; P < 0.05) at 2 and 3 months after treatment. CONCLUSION: BTX-A injection guided by electrical stimulation in combination with physiotherapy was more effective than physiotherapy alone in terms of reducing spasticity and improving functional performance in standing, walking, walking pattern and velocity on spasticity in ankle plantar flexors of ambulant children with CP.