Magnesium acethyltaurate as a potential agent for retinal and optic nerve protection in glaucoma

Glaucoma is the second leading cause of irreversible vision impairment affecting more than 70 million people worldwide with approximately 10%suffering from glaucoma-related bilateral blind（Quigley and Broman,2006）.It is a multi-factorial disease that is characterized by optic nerve damage and visual field loss.Progressive loss of retinal ganglion cells（RGCs）resulting in visual field deficits is the hallmark of glaucoma.

Repair, protection and regeneration of peripheral nerve injury

Reading guide 1778Repair of long-segment peripheral nerve defects1779Bionic reconstruction of hand function after adult brachial plexus root avulsion1780Optimized design of regeneration material for the treatment of peripheral nerve injury1781Synergism of electroactive polymeric materials and electrical stimulation promotes peripheral nerve repair1783Schwann cell effect on peripheral nerve repair and regeneration .

Changes of norepinephrine and tumor necrosis factor in submandibular gland of rats with sympathetic nerve injury and the protective effect of 17 beta-estradiol

BACKGROUND： Recent researches have indicated that estrogen has extensive neuroprotective effects. So some studies designed ovariectomized animal models and administrated with estrogen, so as to verify its neuroprotective effects. OBJECTIVE： To observe the effect of 17 beta-estradiol on the content of norepinephrine （NE） and level of tumor necrosis factor （TNF） in submandibular glands of rats with sympathetic nerve injury, and analyze the dose-dependence and pathway of action. DESIGN： A randomized control animal study SETTINGS： Department of Hand Surgery, the 252 Hospital of Chinese PLA; Department of Hand Surgery Union Hospital affiliated to Tongji Medical College, Huazhong University of Science and Technology. MATERIALS： Fifty healthy female Wistar rats were randomly divided into 5 groups with 10 rats in each group： sham-operated group, ovariectomy＋6-OHDA＋saline group, ovariectomy＋6-OHDA＋17β-estradiol 50, 200 and 500 μg/kg groups. METHODS： The experiments were carried out in Tongji Medical College, Huazhong University of Science and Technology between October 2005 and March 2006. Bilateral ovaries were only exposed but not resected for the rats in the sham-operated group, but bilateral ovaries were resected in all the other groups. In the ovariectomy＋6-OHDA＋176-estradiol 50, 200 and 500 μg/kg groups, the rats were administrated with intraperitoneal injection of 6-OHDA （8 mg/kg）, and then immediately given 176-estradiol of corresponding dosages respectively, once a day for 10 days continuously. Rats in the sham-operated group and ovariectomy＋6-OHDA＋saline group were administrated with saline of the same volume. After administration, 5 rats in each group were killed to determine the NE contents in bilateral submandibular glands with high performance liquid chromatography-electrochemical detector （HPLC-ECD）, and the other 5 rats were used to determine the TNF levels in submandibular glands with enzyme-linked immunosorbant assay. MAIN OUTCOME MEASURES： The NE contents and TNF levels in submandibular glands of rats in each group were observed. RESULTS： All the 50 rats were involved in the analysis of results. （1） The NE content was obviously lower in the ovariectomy＋6-OHDA＋saline group than in the sham-operated group [（1 035±196）, （1 823±314） ng/g, P 〈 0.05], there were no significant differences between the ovariectomy＋6-OHDA＋17β-estradiol 50 μg/kg group and ovariectomy＋6-OHDA＋saline group [（1 004±253）, （1 035±196） ng/g, P 〉 0.05], but obviously higher in the ovariectomy＋6-OHDA＋17β-estradiol 200 and 500 μg/kg groups than in the ovariectomy＋6-OHDA＋saline group [（1 487±268）, （1 939±274）, （1 035±196） ng/g, P 〈 0.05]. （2） The TNF level was obviously higher in the ovariectomy＋6-OHDA＋saline group than in the sham-operated group [（3.498±0.792）, （1.893±0.533） ng/g, P 〈 0.05], there were no significant differences between the ovariectomy＋ 6-OHDA＋17β-estradiol 50 μg/kg group and ovariectomy＋6-OHDA＋saline group [（3.328 ±0.712）, （3.498±0,792） ng/g, P 〉 0.05], but obviously lower in the ovariectomy＋6-OHDA＋17β-estradiol 200 and 500 μg/kg groups than in the ovariectomy＋6-OHDA＋saline group [（2.639±0.438）, （2.016±0.619）, （3.498＋0.792） ng/g, P 〈 0.05]. CONCLUSION： Estrogen has obvious protective effect dose-dependently on 6-OHDA induced chemical sympathetic nerve terminal injury in rats, and it may play its protective role by reducing TNF level and ameliorating inflammatory reaction.

Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging

Some in vitro experiments have shown that erythropoietin （EPO） increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging （PWI） and diffusion-weighted imaging （DWI） have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO （5,000 U/kg） 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling （TUNEL） were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

Acupuncture through Baihui (DU20) to Qubin (GB7) mitigates neurological impairment after intracerebral hemorrhage

Inflammation plays an important role in nerve defects caused by intracerebral hemorrhage. Repairing brain damage by inhibiting the macrophage-inducible C-type lectin/spleen tyrosine kinase （Mincle/Syk） signaling pathway is a potential new target for treating cerebral hemorrhage. In this study, we aimed to determine whether acupuncture through Baihui （DU20） to Qubin （GBT） is an effective treatment for intracerebral hemorrhage through the Mincle/Syk signaling pathway. An intracerebral hemorrhage rat model was established by autol- ogous blood infusion into the caudate nucleus. Acupuncture through Baihui to Qubin was performed for 30 minutes, once every 12 hours, for a total of three times. Piceatannol （34.62 mg/kg）, a Syk inhibitor, was intraperitoneally injected as a control. Modified neurological severity score was used to assess neurological function. Brain water content was measured. Immunohistochemistry and western blot assay were used to detect immunoreactivity and protein expression levels of Minde, Syk, and CARD9. Real-time polymerase chain reaction was used to determine interleukin-1[~ mRNA levels. Hematoxylin-eosin staining was performed to observe histopathological changes. Our re- suits showed that acupuncture through Baihui to Qubin remarkably improved neurological function and brain water content, and inhibited immunoreactivity and expression of Mincle, Syk, CARDg, and interkeukin-1β Moreover, this effect was similar to piceatannol. These find- ings suggest that acupuncture through Baihui to Qubin can improve neurological impairment after cerebral hemorrhage by inhibiting the Mincle/Syk signaling pathway.

Improvement of MDA and SOD Expression and Optic Neuroprotection in Glaucoma Mice by Travoprost and β-Blocker

Objective:The goal of this study was to see if travoprost and β-blockers improved MDA and SOD expression as well as neuroprotection in glaucoma mice.Methods:One hundred healthy SPF SD rats were randomly allocated into five groups:travoprost and β-blocker group,travoprost group,β-blocker group,model group and blank group,with 20 rats in each group.We created a glaucoma mouse model in which the blank group and the model group received the same volume of saline,the β-blocker group received β-blocker,the travoprost group received travoprost,and the travo Prost and β-blocker groups received travo Prost and βreceptor blockers.Retinal cell apoptosis level,intraocular pressure level,MDA and SOD levels were measured after drug administration.Results:The results showed that the levels of intraocular pressure,the apoptosis rate of optic nerve,SOD and MDA of retina in travoprost and β-blocker group,travoprost group,β-blocker group and model group were greater than those in blank group(P<0.05).In comparison to the model group,the intraocular pressure level,optic nerve apoptosis rate,and retinal MDA level in the travoprost and β-blocker group continued to fall,while the retinal SOD level was considerably elevated(P<0.05).The continuous application of travoprost and β-blocker resulted in a constant drop in intraocular pressure,optic nerve apoptosis rate and MDA level in the retina,whereas the SOD level was dramatically elevated(P<0.05).Conclusion:In glaucoma mice,travoprost in combination with a β-blocker can greatly increase MDA expression,SOD and neuroprotection.

TGF-β_1 in retinal ganglion cells in rats with chronic ocular hypertension: its expression and anti-apoptotic effect

AIM: To investigate the anti-apoptotic effect of transforming growth factor beta-1 (TGF-β1) on chronic ocular hypertension. METHODS: The expression of TGF-β1 in retinal ganglion cells (RCGs) was measured using the immunohistochemiscal S-P method and real-time PCR in the normally control group, the ocular hypertension group (experimental group A), the ocular hypertension plus antibody intervention group (experimental group B) and the ocular hypertension plus antigen intervention group (experimental group C) at 1, 2, 3 and 4 weeks postoperatively. The count of apoptotic RCGs was measured using the TUNEL method. RESULTS: The expression of TGF-β1 was significantly higher in experimental group C than that in other three groups (P<0.05). The expression was the lowest in experimental group B (4.17%). A statistically significant difference was noted between the four groups (P <0.01). The count of apoptotic RCGs was statistically significantly lower in experimental group C than that in the experimental groups A and B (P <0.01). A statistically significant difference was noted in the count of apoptotic RCGs between these three experimental groups (P <0.01). CONCLUSION: TGF-β1 can inhibit the apoptosis of RCGs in rats with chronic ocular hypertension.