Protective effects of lycium barbarum polysaccharides on cerebral edema and blood-brain barrier disruption after ischemic stroke

Young Investigators Symposium I (Y3) - Di YangBACKGROUND: Ischemic stroke is a destructive cerebrovascular disease and one of the leading causes of death worldwide. The long term disability after stroke induces heavy burden both to the patients and the society. Yet, no effective neuroprotective agents are available. The polysaccharides extracted from the fruits of wolfberry, Lycium barbarum (LBP), showed neuroprotective and immune-modulative functions. We aim to evaluate the protective effects of LBP in experimental stroke using a focal cerebral ischemia/reperfusion (I/R) model. METHODS: C57BL/6N mice were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by 22 h of reperfusion. Prior to ischemia induction, animals were treated with either vehicle (PBS) or LBP daily for 7 days. Mice were evaluated for neurological deficits just before sacrifice. Brains were harvested for infarct size estimation, water content measurement and immunohistochemical analysis as well as Western blot experiments. Evans blue (EB) extravasation experiment was performed to determine blood-brain barrier (BBB) disruption after MCAO. RESULTS: LBP treatment significantly improved neurological scores and decreased infarct size, hemispheric swelling and water content as well as reduced EB extravasation. In addition, fewer apoptotic cells were identified in the LBP-treated brains by TUNEL assay. Immunoreactivity for aquaporin-4 and glial fibrillary acidic protein were also significantly decreased in LBP-treated brains. We further observed a reduction of nuclear factor-κB translocation and IκB expression after LBP treatment. CONCLUSION: Seven-day LBP pre-treatment effectively improved neurological deficits, decreased infarct size and cerebral edema as well as protected the brain from BBB disruption, aquaporin water channel up-regulation and glial activation. The protective effects of LBP might partially act through its anti-inflammatory effects. The present study suggests that LBP may be used as a preventive neuroprotectant for ischemic stroke.postprin

Lycium barbarum polysaccharides reduce neuronal damage, blood-retinal barrier disruption and oxidative stress in retinal ischemia/reperfusion injury

Neuronal cell death, glial cell activation, retinal swelling and oxidative injury are complications in retinal ischemia/ reperfusion (I/R) injuries. Lycium barbarum polysaccharides (LBP), extracts from the wolfberries, are good for "eye health" according to Chinese medicine. The aim of our present study is to explore the use of LBP in retinal I/R injury. Retinal I/R injury was induced by surgical occlusion of the internal carotid artery. Prior to induction of ischemia, mice were treated orally with either vehicle (PBS) or LBP (1 mg/kg) once a day for 1 week. Paraffin-embedded retinal sections were prepared. Viable cells were counted; apoptosis was assessed using TUNEL assay. Expression levels of glial fibrillary acidic protein (GFAP), aquaporin-4 (AQP4), poly(ADP-ribose) (PAR) and nitrotyrosine (NT) were investigated by immunohistochemistry. The integrity of blood-retinal barrier (BRB) was examined by IgG extravasations. Apoptosis and decreased viable cell count were found in the ganglion cell layer (GCL) and the inner nuclear layer (INL) of the vehicle-treated I/R retina. Additionally, increased retinal thickness, GFAP activation, AQP4 up-regulation, IgG extravasations and PAR expression levels were observed in the vehicle-treated I/R retina. Many of these changes were diminished or abolished in the LBP-treated I/R retina. Pre-treatment with LBP for 1 week effectively protected the retina from neuronal death, apoptosis, glial cell activation, aquaporin water channel up-regulation, disruption of BRB and oxidative stress. The present study suggests that LBP may have a neuroprotective role to play in ocular diseases for which I/R is a feature. © 2011 Li et al.published_or_final_versio

A New Role for Translation Initiation Factor 2 in Maintaining Genome Integrity

Escherichia coli translation initiation factor 2 (IF2) performs the unexpected function of promoting transition from recombination to replication during bacteriophage Mu transposition in vitro, leading to initiation by replication restart proteins. This function has suggested a role of IF2 in engaging cellular restart mechanisms and regulating the maintenance of genome integrity. To examine the potential effect of IF2 on restart mechanisms, we characterized its influence on cellular recovery following DNA damage by methyl methanesulfonate (MMS) and UV damage. Mutations that prevent expression of full-length IF2-1 or truncated IF2-2 and IF2-3 isoforms affected cellular growth or recovery following DNA damage differently, influencing different restart mechanisms. A deletion mutant (del1) expressing only IF2-2/3 was severely sensitive to growth in the presence of DNA-damaging agent MMS. Proficient as wild type in repairing DNA lesions and promoting replication restart upon removal of MMS, this mutant was nevertheless unable to sustain cell growth in the presence of MMS; however, growth in MMS could be partly restored by disruption of sulA, which encodes a cell division inhibitor induced during replication fork arrest. Moreover, such characteristics of del1 MMS sensitivity were shared by restart mutant priA300, which encodes a helicase-deficient restart protein. Epistasis analysis indicated that del1 in combination with priA300 had no further effects on cellular recovery from MMS and UV treatment; however, the del2/3 mutation, which allows expression of only IF2-1, synergistically increased UV sensitivity in combination with priA300. The results indicate that full-length IF2, in a function distinct from truncated forms, influences the engagement or activity of restart functions dependent on PriA helicase, allowing cellular growth when a DNA–damaging agent is present

In situ hybridization study of pro-opiomelanocortin (POMC) gene expression in human pituitary corticotrophs and their adenomas

Pro-opiomelanocortin (POMC) mRNA was detected on paraffin sections by in situ hybridization (ISH) in corticotrophs of 12 nontumorous pituitaries, 11 functioning corticotroph, and 11 silent pituitary adenomas. ISH combined with immunocytochemistry for adrenocorticotrophic hormone (ACTH), a POMC-derived peptide, was also performed. ACTH immunoreactive cells of the anterior lobes and those invading the posterior lobe showed a high or moderate level of POMC mRNA that was not correlated with the intensity of ACTH immunoreactivity. Variable levels of POMC gene expression were present in Crooke's cells, corticotrophs suppressed by glucocorticoid excess. Most functioning corticotroph adenomas and silent subtype 1 adenomas had an intense hybridization signal and ACTH immunoreactivity. In silent subtype 2 and 3 adenomas, POMC mRNA had a diffuse low level or was absent; in these adenomas ACTH immunoreactivity was diffuse, restricted to some cells, or negative. The results indicate that POMC gene is expressed in both normal and suppressed nontumorous corticotrophs. Intense signals for POMC mRNA are found in most functioning corticotroph adenomas. The difference between POMC gene expression in silent 1 and silent 2 and 3 adenomas suggests that different mechanisms are responsible for the lack of endocrine activity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47518/1/428_2005_Article_BF01600224.pd

The immunopathology of canine vector-borne diseases

The canine vector-borne infectious diseases (CVBDs) are an emerging problem in veterinary medicine and the zoonotic potential of many of these agents is a significant consideration for human health. The successful diagnosis, treatment and prevention of these infections is dependent upon firm understanding of the underlying immunopathology of the diseases in which there are unique tripartite interactions between the microorganism, the vector and the host immune system. Although significant advances have been made in the areas of molecular speciation and the epidemiology of these infections and their vectors, basic knowledge of the pathology and immunology of the diseases has lagged behind. This review summarizes recent studies of the pathology and host immune response in the major CVBDs (leishmaniosis, babesiosis, ehrlichiosis, hepatozoonosis, anaplasmosis, bartonellosis and borreliosis). The ultimate application of such immunological investigation is the development of effective vaccines. The current commercially available vaccines for canine leishmaniosis, babesiosis and borreliosis are reviewed

Neuroprotective effects of Lycium barbarum polysaccharides on retinal ischemic injury

Purpose: Retinopathy is a common complication of diabetes. As the disease progresses, regional failure of the microvascular circulation will lead to retinal ischemia. Therefore, retinal ischemic injury is common in patients with diabetes. In the present study, we aimed to evaluate the effects of Lycium barbarum polysaccharides (LBP), a well known traditional Chinese medicine, on retinal ischemic injury in a mouse in vivo ischemia model. Methods: Mice were orally treated with either vehicle or LBP (1 mg/kg or 10 mg/kg) for 1 week before induction of retinal ischemia by the intraluminal suture method. After 2 hours of retinal ischemia followed by 22 hours of reperfusion, retinae were immediately collected, fixed, and paraffin-embedded for subsequent histological analysis. The morphology of retinal cells and the thickness of various retinal layers were determined from hematoxylin and eosin stained sections. The number of apoptotic cells was also determined by TUNEL assay. Results: Severe neuronal cell death was found in the ganglion cell and inner nuclear layers of retinae from the vehicle-treated group. On the other hand, the number of viable cells was significantly increased in the retinae of LBP-treated groups when compared with those of the vehicle-treated group. This finding of less neuronal cell death in the LBP-treated groups was further confirmed by TUNEL assay where much fewer apoptotic cells were identified. In addition, by measuring the thickness of the ganglion cell layer, inner plexiform layer and inner nuclear layer, we found that ischemia-induced retinal swelling was reduced in both LBP-treated groups (P<0.05 in 10 mg/kg group). Conclusions: Taken together, these data indicate that treatment with LBP for 1 week could protect the mouse from retinal ischemic injury via reducing neuronal cell death and retinal swelling. Our present study hence suggests that LBP may be used as a preventive medicine for diabetic retinopathy

Protective effects of lycium barbarum polysaccharides on cerebral edema and blook-brain barrier disruption after ischemic stroke

Poster Session 361 - Ischemia: Neuroprotection II: no. 361.01/DD13BACKGROUND: Ischemic stroke is a destructive cerebrovascular disease and one of the leading causes of death worldwide. The long term disability after stroke induces heavy burden both to the patients and the society. Yet, no effective neuroprotective agents are available. The polysaccharides extracted from the fruits of wolfberry, Lycium barbarum (LBP), showed neuroprotective and immune-modulative functions. We aim to evaluate the protective effects of LBP in experimental stroke using a focal cerebral ischemia/reperfusion (I/R) model. METHODS: C57BL/6N mice were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by 22 h of reperfusion. Prior to ischemia induction, animals were orally fed with either vehicle (PBS) or LBP daily for 7 days. Mice were evaluated for neurological deficits just before sacrifice. Brains were harvested for infarct size estimation, water content measurement and immunohistochemical analysis as well as Western blot experiments. Evans blue (EB) extravasation experiment was performed to determine blood-brain barrier (BBB) disruption after MCAO. RESULTS: LBP treatment significantly improved neurological scores and decreased infarct size, hemispheric swelling and water content as well as reduced EB extravasation. In addition, fewer apoptotic cells were identified in the LBP-treated brains by TUNEL assay. Immunoreactivity for aquaporin-4 and glial fibrillary acidic protein were also significantly decreased in LBP-treated brains. We further observed a reduction of nuclear factor-κB translocation and IκB expression after LBP treatment.CONCLUSION: Seven-day LBP pre-treatment effectively improved neurological deficits, decreased infarct size and cerebral edema as well as protected the brain from BBB disruption, aquaporin water channel up-regulation and glial activation. The protective effects of LBP might partially act through its anti-inflammatory effects. The present study suggests that LBP may be used as a preventive neuroprotectant for ischemic stroke.link_to_OA_fulltextThe 2011 Annual Meeting of the Society for Neuroscience, Washington, D.C., 12-16 November 2011. In Abstract Book of Neuroscience, 2011, p. 735-73

Protective effects of lycium barbarum polysaccharides on cerebral edema and blood-brain barrier disruption after ischemic stroke

Open Access JournalPoster Session 361 - Ischemia: Neuroprotection 2: abstract no. 361.01/DD13BACKGROUND: Ischemic stroke is a destructive cerebrovascular disease and one of the leading causes of death worldwide. The long term disability after stroke induces heavy burden both to the patients and the society. Yet, no effective neuroprotective agents are available. The polysaccharides extracted from the fruits of wolfberry, Lycium barbarum (LBP), showed neuroprotective and immune-modulative functions. We aim to evaluate the protective effects of LBP in experimental stroke using a focal cerebral ischemia/reperfusion (I/R) model. METHODS: C57BL/6N mice were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by 22 h of reperfusion. Prior to ischemia induction, animals were orally fed with either vehicle (PBS) or LBP daily for 7 days. Mice were evaluated for neurological deficits just before sacrifice. Brains were harvested for infarct size estimation, water content measurement and immunohistochemical analysis as well as Western blot experiments. Evans blue (EB) extravasation experiment was performed to determine blood-brain barrier (BBB) disruption after MCAO. RESULTS: LBP treatment significantly improved neurological scores and decreased infarct size, hemispheric swelling and water content as well as reduced EB extravasation. In addition, fewer apoptotic cells were identified in the LBP-treated brains by TUNEL assay. Immunoreactivity for aquaporin-4 and glial fibrillary acidic protein were also significantly decreased in LBP-treated brains. We further observed a reduction of nuclear factor-κB translocation and IκB expression after LBP treatment. CONCLUSION: Seven-day LBP pre-treatment effectively improved neurological deficits, decreased infarct size and cerebral edema as well as protected the brain from BBB disruption, aquaporin water channel up-regulation and glial activation. The protective effects of LBP might partially act through its anti-inflammatory effects. The present study suggests that LBP may be used as a preventive neuroprotectant for ischemic stroke.link_to_OA_fulltextThe 2011 Annual Meeting of the Society for Neuroscience (SfN 2011), Washington, D.C., 12-16 November 2011

Neuroprotective effects of Lycium barbarum polysaccharides on ischemic stroke injury

Program/Poster no. 150.13/K2Poster session: 150.Ischemia: Neuroprotection Animal ModelsObjective: The polysaccharides in Lycium barbarum, a well known traditional Chinese medicine, have been demonstrated to possess multiple biological effects including anti-aging, anti-tumor, cytoprotective, and neuromodulation. In the present study, we aimed to evaluate the effects of Lycium barbarum polysaccharides (LBP) on brain ischemic injury in a mouse Middle Cerebral Artery Occlusion (MCAO) model. Methods: Mice were orally treated with either vehicle (PBS) or LBP (1 mg/kg or 10 mg/kg) for 1 week before induction of brain ischemia by MCAO. After 2 hours of ischemia followed by 22 hours of reperfusion, animals were evaluated for neurological deficits. Immediately after scoring of the neurological deficits, brains were isolated, cut into 6 coronal slices of 2 mm thickness and stained with 2% 2,3,5-triphenyltetrazolium chloride (TTC) to detect lesion areas. The posterior surface of each brain slice was subsequently photographed and analyzed using a digital image analysis system. Infarct area, volume, and hemispheric brain swelling were calculated using an indirect method in which the effects of edema and brain swelling have been normalized. Results: Neurological deficits were scored as follows: 0, no observable neurological deficits (normal); 1, failure to extend opposite forepaw (mild); 2, circling to the contralateral side (moderate); and 3, loss of walking and righting reflex (severe). Our results showed that mice treated with either 1 mg/kg LBP or 10 mg/kg LBP (n=7 for each group) had less neurological deficits than the vehicle-treated mice (n=8) (vehicle=2.0±0.3, 1 mg/kg LBP=1.4±0.2, 10 mg/kg LBP=1.1±0.1; P<0.05 (by Mann-Whitney test) for vehicle vs. 10 mg/kg LBP). Moreover, the infarct area of brain slice number 4 was significantly reduced in the LBP-treated mice when compared with the vehicle-treated mice (vehicle=35.4±4.2%, 1 mg/kg LBP=17.5±5.8%, 10 mg/kg LBP=17.6±4.9%). Consistent with the infarct area data, the overall infarct volumes were decreased in the LBP-treated groups (vehicle=25.8±3.1%, 1 mg/kg LBP=21.5±2.5%, 10 mg/kg LBP=16.6±2.7%). In addition, less hemispheric brain swelling was also found in mice with the LBP treatment (vehicle=11.1±0.9%, 1 mg/kg LBP=9.7±1.1%, 10 mg/kg LBP=7.9±0.6%). Conclusions: Taken together, these data indicate that treatment with LBP for 1 week could protect the mouse from brain ischemic injury. Our present study suggests that LBP may be used as a preventive medicine for stroke.link_to_OA_fulltex