Neuroprotective effects of Xiao-Xu-Ming decoction against ischemic neuronal injury in vivo and in vitro

Ethnopharmacological relevance

Xiao-Xu-Ming decoction (XXMD) has long been employed clinically to treat stroke in traditional Chinese Medicine.

Aim of the study

To investigate the neuroprotective effects of XXMD in vivo and in vitro stroke models and determine involved mechanisms.

Materials and methods

Two models (four-vessel occlusion in adult Wistar rats and oxygen–glucose deprivation primary cultured neurons) were employed to mimic ischemia-reperfusion damage, in vivo and in vitro, respectively. The effects of XXMD were investigated with respect to neuronal damage, activity of caspase-3 and expression of Bcl-2 in CA1 region of hippocampus after ischemia. The cognitive ability was measured 7 days after ischemia/reperfusion by using Morris water maze.

Results

Oral administration of XXMD significantly increased the density of neurons that survived in the CA1 region of hippocampus on the 3rd and 7th day after transient global ischemia was induced in a dose-dependent manner. XXMD ameliorated severe deficiencies in spatial cognitive performance induced by transient global ischemia. Inhibition of caspase-3 activity and up-regulation of Bcl-2 expression were induced in the high dose of XXMD-treated rats after ischemia. In oxygen–glucose deprivation model, both XXMD extract and drug-containing serum prepared from blood of high dose of XXMD-treated rats inhibited apoptotic neuronal death at 24 h after reoxygenation.

Conclusions

Our results clearly demonstrated that XXMD is neuroprotective and appears to influence deleterious pathological processes that are activated after the onset of ischemia.     

Combinatorial effects of conception and governor vessel electroacupuncture and human umbilical cord blood-derived mesenchymal stem cells on pathomorphologic lesion and cellular apoptosis in rats with cerebral ischemia/reperfusion

Objective

To investigate the combinatorial effects of conception and governor vessel electroacupuncture (EA) and human umbilical cord blood-derived mesenchymal stem cells (HUCB-MSCs) on pathomorphologic lesion and cellular apoptosis in rats with cerebral ischemia/reperfusion.

Methods

With the HUCB-MSCs isolated, cultured and identified and the models of cerebral ischemia-reperfusion established, the HUCB-MSCs of passage three were intracranially transplanted and the EA at conception and governor vessels was applied. The pathomorphologic lesion by hematoxylin-eosin staining and the cellular apoptosis by terminal deoxynucleotidyl transferase-mediated nick-end labeling method around the ischemic focus were observed.

Results

The cultured adherent HUCB-MSCs exhibited a spindle shape and expressed MSC-specific markers, with the cell purity and proliferation rate significantly increasing after the primary passage. HE staining showed that there were no pathological changes observed in the sham surgery group. However, in the PBS transplantation group, degeneration and necrosis of a great number of nerve cells were seen. In both the HUCB-MSCs transplantation group and the HUCB-MSCs transplantation + EA group, reparative changes of the pathomorphism of the tissue were found. Both combination treatment and simple MSCs treatment were able to improve the pathomorphorlogic lesion following cerebral ischemia and reduce the abnormal TUNEL-positive numbers, with former better than latter.

Conclusion

HUCB-MSCs improve pathological lesions and inhibit the cellular apoptosis around the cerebral ischemic area. EA at conception and governor vessels also improve pathological lesion and inhibit the cellular apoptosis in rats treated with HUCB-MSCs transplantation, which effects were superior to that of simple HUCB-MSCs transplantation.     

Neuroprotective activity of Matricaria recutita Linn against global model of ischemia in rats

Ethnopharmacological relevance

Traditionally, the whole plant is used for various diseases, including neuronal disorders.

Aim of the study

To evaluate the neuroprotective effect of Matricaria recutita L. against global cerebral ischemia/reperfusion (I/R) injury-induced oxidative stress in rats.

Materials and methods

Neuroprotective activity was carried out by global cerebral ischemia on Sprague–Dawley rats by bilateral carotid artery (BCA) occlusion for 30 min followed by 60 min reperfusion. The antioxidant enzymatic and non-enzymatic levels were estimated along with cerebral infarction area and histopathological studies.

Results

The Matricaria recutita L. methanolic extract showed dose-dependent neuroprotective activity by significant decrease in lipid peroxidation (LPO) and increase in the superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and total thiol levels in extract treated groups as compared to ischemia/reperfusion group. Cerebral infarction area was significantly reduced in extract treated groups as compared to ischemia/reperfusion group.

Conclusion

The methanolic extract of Matricaria recutita L. showed potent neuroprotective activity against global cerebral ischemia/reperfusion injury-induced oxidative stress in rats.     

Neuroprotective effect of calycosin on cerebral ischemia and reperfusion injury in rats

Ethnopharmacological relevance

Radix Astragali has been commonly used as traditional herbal medicine in China for reinforcing vital energy, strengthening superficial resistance and promoting the discharge of pus and the growth of new tissue.

Aim of the study

The present study was to investigate the neuroprotective effect of calycosin isolated from the roots of Radix Astragali on cerebral ischemic/reperfusion injury.

Materials and methods

After 24 h of reperfusion following ischemia for 2 h induced by middle cerebral artery occlusion (MCAO), Sprague-Dawley rats were intragastrically administered different doses of calycosin (7.5, 15, 30 mg/kg, respectively). Neurological deficit, infarct volume, histopathology changes and some oxidative stress markers were evaluated after 24 h of reperfusion.

Results

Treatment with calycosin significantly ameliorated neurologic deficit and infarct volume after cerebral ischemia reperfusion. Calycosin also reduced the content of malondialdehyde (MDA), protein carbonyl and reactive oxygen species (ROS), and up-regulated the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px) in a dose-dependent manner. Moreover, calycosin can also inhibit the expression of 4-Hydroxy-2-nonenal (4-HNE).

Conclusion

These results suggest that calycosin has a neuroprotective effect against cerebral ischemia/reperfusion injury. The mechanism might be attributed to its antioxidant effects.     

Protective effect of hydroalcoholic extract of Mimusops elengi Linn. flowers against middle cerebral artery occlusion induced brain injury in rats

Ethnopharmacological relevance

In the traditional Indian and Thai system of medicine, Mimusops elengi Linn., flower is used as brain tonic and to calm anxiety and panic attacks.

Aim of the study

The present study was designed to investigate the neuroprotective effect of hydroalcoholic extract of Mimusops elengi (ME) against cerebral ischemic reperfusion injury in rats.

Materials and methods

Male rats were pretreated with ME (100 and 200 mg/kg) for seven days and focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) method. After 60 min of MCAO and 24 h of reperfusion, a battery of behavioral tests assessed the extent of neurological deficits. Infarct volume and brain edema were measured in TTC stained brain sections and the extent of blood brain barrier (BBB) disruption was observed by Evan's blue extravasation. Oxidative and nitrative stress parameters were estimated in the brain homogenates. Further, simultaneous quantification of five polyphenolic biomarkers were done using HPLC.

Results

Pretreatment with ME at doses of 100 and 200 mg/kg significantly improved the neurobehavioral alterations and reduced the infarct volume, edema and extent of BBB disruption induced by ischemia reperfusion injury. It also prevented the alteration in the antioxidant status and reduced the nitrite levels when compared to ischemic animals. Further, HPLC studies revealed that ME contains five bioactive polyphenolic compounds.

Conclusions

These results clearly indicate the neuroprotective effect of ME against stroke like injury. The observed protective effect might be attributed to the polyphenolic compounds and their antioxidant and anti-inflammatory property.     

Total saponins of Panax Notoginseng modulate the expression of caspases and attenuate apoptosis in rats following focal cerebral ischemia-reperfusion

Ethnopharmacological relevance

Total saponins of Panax notoginseng (TSPN), main constituents extracted from Panax Notoginseng, a highly valued traditional Chinese medicine, have been shown to be an effective agent on cerebral infarction.

Aim of the study

The effects of TSPN on apoptosis and expressions of caspase-1, caspase-3 and caspase-8 were studied after cerebral ischemia for 2 h followed by reperfusion for 46 h in rats.

Materials and methods

Rats were subjected to transient middle cerebral artery occlusion (MCAO) model using the intraluminal thread. TSPN was administered intraperitoneally at 5 min before and 12 h, 24 h and 36 h after MCAO, respectively.

Results

TSPN (at the dose of 25 mg/kg) significantly attenuated TUNEL-positive cells and reduced the expression of caspase-1 and caspase-3 compared to the model group, while it had no obvious effect on the expression of caspase-8.

Conclusions

The neuroprotective effect of TSPN on focal ischemia may be related to inhibition of apoptosis and caspases activation.     

Neuroprotective activityof Cymbopogon martinii against cerebral ischemia/reperfusion-induced oxidative stress in rats

Ethnopharmacological relevance

Cymbopogon martinii (Roxb.) Watson (Family: Graminae), commonly known as Palmarosa, is traditionally prescribed for central nervous system (CNS) disorders such as neuralgia, epileptic fits and anorexia. Although the plant possesses diverse pharmacological actions, the neuroprotective action has got little attention.

Aim of the study

The present study evaluated neuroprotective effect of essential oil of Cymbopogon martinii (EOCM) against global cerebral ischemia/reperfusion (I/R)-induced oxidative stress in rats.

Materials and methods

Global ischemic brain damage was induced by bilateral common carotid artery (BCCA) occlusion for 30 min, followed by 60 min reperfusion on Wistar albino rats. The biochemical levels of lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), total thiols and glutathione (GSH) were estimated and brain coronal sections and histopathological studies were performed.

Results

BCCA occlusion, followed by reperfusion caused varied biochemical/enzymatic alterations viz. increase in LPO and decrease in SOD, CAT, total thiols and GSH. The prior treatment of EOCM (50 mg/kg and 100 mg/kg, p.o. for 10 days) markedly reversed these changes and restored to normal levels as compared to I/R groups. Moreover, brain coronal sections and histopathological studies revealed protection against ischemic brain damage in the EOCM-treated groups.

Conclusion

This study, for the first time, shows potent neuroprotective effect of EOCM against global cerebral I/R-induced oxidative stress in rats, suggesting its therapeutic potential in cerebrovascular diseases (CVD) including stroke.     

Neuroprotective effect of Buyang Huanwu decoction against focal cerebral ischemia/reperfusion injury in rats--time window and mechanism

Ethnopharmacological relevance

Buyang Huanwu Decoction, a traditional Chinese medicine, consists of different herbal medicines, and has been traditionally used for centuries to treat paralysis and stroke. However, its optimal therapeutic time window and the mechanism are still unclear.

Aim of the study

This study was designed to explore the therapeutic time window and mechanism of Buyang Huanwu Decoction on transient focal cerebral ischemia/reperfusion injury.

Materials and methods

Middle cerebral artery occlusion was conducted in male Sprague-Dawley rats, and 40 g/kg of Buyang Huanwu Decoction was intragastrically infused at different time points, and the same dose was infused every 24 h for 3 days. The level of glutamate in cerebrospinal fluid and the expression of metabotropic glutamate receptor-1 RNA in striatum were detected before, during, and after ischemia/reperfusion. Neurological deficit scores and brain infarction volumes were measured at 72 h after reperfusion.

Result

Cerebral ischemia/reperfusion resulted in significant neurological deficit and extensive cerebral infarct volume, associated with a large amount of glutamate in cerebrospinal fluid and elevation of metabotropic glutamate receptor-1 RNA expression. Buyang Huanwu Decoction significantly suppressed the release of glutamate, and reduced the expression of metabotropic glutamate receptor-1 RNA. The neurological defect score and infarction volume were significantly improved by administration of Buyang Huanwu Decoction, when compared with the Ischemia group.

Conclusions

Administration of Buyang Huanwu Decoction, within 4 h of post-transient focal stroke, reduced significant cerebral ischemia/reperfusion damage. The neuroprotective mechanism of Buyang Huanwu Decoction is, in part, associated with the down-regulation of metabotropic glutamate receptor-1 RNA and inhibition of glutamate release resulting from cerebral ischemia.     

Baicalin can scavenge peroxynitrite and ameliorate endogenous peroxynitrite-mediated neurotoxicity in cerebral ischemia-reperfusion injury

Ethnopharmacological relevance

Baicalin is one of the principal flavonoids isolated from the dried root of Scutellaria baicalensis Georgi that has long been used to treat ischemic stroke. However, its neuroprotective mechanisms against cerebral ischemia injury are poorly understood.

Aim of the study

To explore the neuroprotective mechanisms of baicalin against cerebral ischemia reperfusion injury.

Material and methods

In chemical systems, we conducted electron paramagnetic resonance (EPR) spin trapping experiments to evaluate the scavenging effects of baicalin on superoxide and nitric oxide, and mass spectrometry (MS) studies on the reaction of baicalin and peroxynitrite. In cellular experiments, we investigated the effects of baicalin against extraneous and endogenous peroxynitrite mediated neurotoxicity in SH-SY5Y cells treated with peroxynitrite donor, synthesized peroxynitrite and exposed to oxygen glucose deprivation and reoxygenation (OGD/RO) in vitro. Moreover, we studied the neuroprotective effects of baicalin by using a rat model of middle cerebral artery occlusion in vivo. FeTMPyP, a peroxynitrite decomposition catalyst, was used as positive control. Cell viability and apoptotic cell death was accessed by MTT assay and TUNEL assay respectively; 3-nitrotyrosine formation and infarction volume were detected by immunostaining experiments and TTC staining respectively.

Results

Baicalin revealed strong antioxidant ability by directly scavenging superoxide and reacting with peroxynitrite. Baicalin protected the neuronal cells from extraneous and endogenous peroxynitrite-induced neurotoxicity. In ischemia-reperfused brains, baicalin inhibited the formation of 3-nitrotyrosine, reduced infarct size and attenuated apoptotic cell death, whose effects were similar to FeTMPyP.

Conclusions

Baicalin can directly scavenge peroxynitrite and the peroxynitrite-scavenging ability contributes to its neuroprotective mechanisms against cerebral ischemia reperfusion injury.     

Neuroprotective effect of Artemisia absinthium L. on focal ischemia and reperfusion-induced cerebral injury

Ethnopharmacological relevance

Artemisia absinthium L. has long been used as traditional herbal medicine in China, Europe and Pakistan for the treatment of gastric pain, cardiac stimulation, to improve memory and for the restoration of declining mental function.

Aim of the study

The present study was designed to investigate the potential protective effects of Artemisia absinthium on cerebral oxidative stress and damage as well as behavioral disturbances induced by cerebral ischemia and reperfusion injury in rats.

Materials and methods

Focal ischemia and reperfusion were induced by middle cerebral artery occlusion (MCAO) for 90 min, followed by 24 h reperfusion. MCAO led to significant rise in infarct size and lipid peroxidation, and depletion in glutathione content, superoxide dismutase and catalase activity in brain. Further, behavioral deficits like motor incoordination and impairment of short-term memory were also significantly impaired by MCAO as compared with sham group.

Results

The brain oxidative stress and damage, and behavioral deficits were significantly attenuated by pre-treatment with the methanol extract of Artemisia absinthium (100 mg/kg and 200 mg/kg, p.o.).

Conclusion

These findings suggested that Artemisia absinthium is neuroprotective and may prove to be useful adjunct in the treatment of stroke.     

Neuroprotective effect of modified Wu-Zi-Yan-Zong granule,a traditional Chinese herbal medicine,on CoCl2-induced PC12 cells

Aim of the study

To investigate the neuroprotective effect of aqueous extract of modified Wu-Zi-Yan-Zong granule (MWG), a traditional Chinese herbal medicine, against CoCl₂-induced neurotoxicity in PC12 cells.

Materials and methods

Cell viability assay, apoptosis rate assay, ROS detection and mitochondrial membrane potential (MMP) assay were performed. In addition, cytochrome c, caspase-3, PARP and MAPKs were also detected by Western blotting.

Results

MWG extract increased viability and suppresses early and middle/late stage apoptosis in a dose-dependent manner in CoCl₂-induced PC12 cells. Moreover, MWG extract decreased the level of intracellular reactive oxygen species (ROS), increased MMP, regulated Bcl-2 family protein expression (Bcl-2 and Bcl-XL) and inhibited the release of cytochrome c from the mitochondria. In addition, MWG extract attenuated activation of caspase-3 and poly ADP-ribose polymerase (PARP) and inhibited the phosphorylation of ERK, c-Jun NH₂-terminal kinase (JNK) and p38 MAPKs.

Conclusions

MWG extract exhibited significant neuroprotective effect on PC12 cells, and this effect may be associated with the suppression of ROS generation and inhibition of mitochondria-mediated caspase and MAPK signaling pathways.     

小续命汤有效成分组对脑缺血/再灌注大鼠恢复早期脑线粒体的保护作用研究

观察小续命汤有效成分组对脑缺血/再灌注大鼠恢复早期脑线粒体的作用,研究其对脑缺血/再灌注大鼠恢复早期的神经保护作用机制。采取插线法制备大鼠大脑中动脉阻塞脑缺血模型,2 h后再灌注。应用Zea-Longa's级标准评分法评价动物脑缺血程度,将模型成功大鼠随机分为模型组、小续命汤有效成分低、中、高剂量组和阳性药金纳多组,以假手术大鼠作为对照组。于给药5 d后梯度离心提取大鼠脑组织缺血周边区线粒体,通过Clark氧电极法检测线粒体呼吸功能,荧光探针法检测线粒体内ROS含量及线粒体膜电位,分光光度法检测线粒体琥珀酸脱氢酶活性和脑组织ATP含量。结果显示,小续命汤有效成分组能够显著改善脑缺血再灌注大鼠恢复早期脑线粒体的呼吸功能,提高线粒体琥珀酸脱氢酶的活性,降低线粒体ROS的含量,提高脑线粒体膜电位,促进脑组织ATP的合成。提示小续命汤有效成分组能够明显减轻脑缺血再灌注早期导致的脑组织能量代谢紊乱,改善脑线粒体结构和功能损伤,说明小续命汤有效成分组对脑线粒体的保护作用可能是其发挥神经保护的作用机制之一。     

Electroacupuncture effect on neurological behavior and tyrosine kinase-JAK 2 in rats with focal cerebral ischemia

Objective

Electroacupuncture effect on neurological behavior and the expression of tyrosine kinase Janus kinase 2 (JAK 2) of ischemic cortex in rats with the focal cerebral ischemia were investigated in this study.

Methods

The model of focal cerebral ischemia was established by the heat-coagulation induced the occlusion of the middle cerebral artery. The electro-acupuncture was applied on Baihui (GV 20) and Dazhui (GV 14), and AG490 was applied by intracerebroventricular infusion. The expressions of JAK2 mRNA and phospharylated JAK2 (p-JAK2) in the ischemic cortex were observed by in situ hybridization and western blotting.

Results

The expressions of JAK2 mRNA and p-JAK2 were rarely found in sham surgery group. In model group, the expression of JAK2 mRNA and JAK2 phosphorylation had increased. After 1 day of cerebral ischemia, the expression had reached its peak. After cerebral ischemia, the expressions of JAK2 mRNA and p-JAK2 were consistent with the neurological deficit score. Electroacupuncture treatment and AG490 intervention were able to improve the neurological deficit score after cerebral ischemia, and down-regulate the expressions of JAK2 mRNA and JAK2 phosphorylation.

Conclusion

After cerebral ischemia, the excessive expressions of JAK2 and the JAK2 phosphorylation would be one of mechanisms by which the brain injury got worse. The therapy of electro-acupuncture could reduce the expression of JAK2, and inhibit JAK2 phosphorylated activation, so as to block the abnormal activation of signal transduction pathway which was induced by JAK2.     

An-Gong-Niu-Huang Wan protects against cerebral ischemia induced apoptosis in rats: Up-regulation of Bcl-2 and down-regulation of Bax and caspase-3

Ethnopharmacological relevance

The An-Gong-Niu-Huang Wan (AGNH), a Chinese traditional medicine, has been used for treatment of cerebral diseases for centuries in China and other Asian countries, and is approved by the State Food and Drug Administration of China for the treatment of stroke. The aim of present study is to test the neuroprotective effects of AGNH on cerebral ischemia in rats and to explore the underlying mechanisms.

Materials and methods

75 Male Sprague-Dawley rats were randomly divided into 5 groups: sham, ischemia–reperfusion (I/R), and I/R plus 0.065 g/kg/d AGNH, 0.125 g/kg/d AGNH and 0.25 g/kg/d AGNH. Cerebral ischemia was induced by 1.5 h of middle cerebral artery occlusion (MCAO). Neurological functional deficits were evaluated according to Zea longa?s score, cerebral infarct area was measured by tetrazolium staining. Cell injury and apoptosis were assessed by Nissl staining and DNA fragmentation assay. The expression of Bax, Bcl-2 and caspase-3 were analyzed by Western blot.

Results

Rats subjected to MCAO exhibited worsened neurological score, infarct area, cell damage and apoptosis. These were all attenuated by AGNH (0.125 and 0.25 g/kg/d). Moreover, AGNH reversed cerebral ischemia induced decreases in Bcl-2 expression and increases in Bax and caspase-3 expression.

Conclusions

These results suggest that AGNH exerts neuroprotective effects, and the neuroprotection is likely to relate to depressed Bax/Bcl-2 ratio and caspase-3 level, leading to inhibition of apoptotic cell death.     

Neuroprotective effects of a standardized flavonoid extract from Diospyros kaki leaves

Ethnopharmacological relevance

Flavonoids, extracted from the leaves of Diospyros kaki, are the main therapeutic components of NaoXingQing (NXQ), a potent and patented Chinese herbal remedy widely used in China for the treatment of apoplexy syndrome.

Aim of the study

To investigate the neuroprotective effects of FLDK-P70, a standardized flavonoid extract, using in vivo rat models of both focal ischemia/reperfusion (I/R) injury induced by middle cerebral artery occlusion (MCAO) and on transient global brain ischemia induced by four-vessel occlusion (4-VO). We also aim to examine the effects of FLDK-P70 on glutamate-induced cell injury of hippocampal neurons as well as on hypoxia-induced injury of cortical neurons in primary cell culture.

Materials and methods and results

Administration of FLDK-P70 for 12 days (40, 80 mg/kg body weight, p.o., 5 days before and 7 days after 4-VO) increased the survival of hippocampal CA1 pyramidal neurons after transient global brain ischemia. Similarly, administration of FLDK-P70 for 7 days (40, 80 mg/kg body weight, p.o., 3 days before and 4 days after MCAO) significantly reduced the lesion of the insulted brain hemisphere and improved the neurological behavior of rats. In primary rat hippocampal neuronal cultures, pretreatment with FLDK-P70 (5, 10 μg/ml) protected neurons from glutamate-induced excitotoxic neuronal death in a dose-dependent manner. In primary rat cerebral cortical neuronal culture, pretreatment with FLDK-P70 (25, 100 μg/ml) also reduced hypoxia–reoxygen induced neuronal death and apoptosis in a dose-dependent manner.

Conclusions

These in vivo and in vitro results suggest that FLDK-P70 significantly protects rats from MCAO and 4-VO ischemic injury in vivo and protects hippocampal neurons from glutamate-induced excitotoxic injury as well as cortical neurons from hypoxia-induced injury in vitro. The mechanisms of these effects may be due to the antioxidative activity of the flavonoids. These results convincingly demonstrate that FLDK-P70 may be useful for the prevention and treatment of ischemia/reperfusion injury and other related neurodegenerative diseases.     

Magnesium lithospermate B improves myocardial function and prevents simulated ischemia/reperfusion injury-induced H9c2 cardiomyocytes apoptosis through Akt-dependent pathway

Ethnopharmacological relevance

Magnesium lithospermate B (MLB), an active polyphenol acid of Radix Salviae Miltiorrhizae (Danshen), showed a wide range of pharmacological activities in cardiovascular diseases. However, its role in protection against ischemia/reperfusion injury in H9c2 cardiomyocytes has not been elucidated. This study was aimed to investigate the protective effect and potential molecular mechanisms of MLB on apoptosis in H9c2 cardiomyocytes in vitro.

Materials and methods

We tested cell viability, shortening amplitude, necrosis, apoptosis, and the expression levels of Akt, phosphorylated Akt, Bcl-2 and Bax after 2-h simulated ischemia and 24-h simulated reperfusion in H9c2 cardiomyocytes. We further observed the contractile function in hearts after they were subjected to global 30-min ischemia and 180-min reperfusion.

Results

Pretreatment with MLB markedly increased cell viability and while reducing evidence of necrosis and apoptosis in H9c2 cardiomyocytes. In addition, the expression of Bcl-2 and Bax protein was modulated. The results also showed that MLB significantly increased phosphorylation of Akt and that this phosphorylation can be partially inhibited by phosphoinositide 3-kinase/Akt inhibitor. Furthermore, MLB improved MI/R-induced myocardial contractile function.

Conclusion

Our results showed that MLB prevents I/R-induced myocardial damage by reducing necrosis and apoptosis in H9c2 cardiomyocytes and improving myocardial function in rat hearts.     

Neuroprotective effects of tongluojiunao in neurons exposed to oxygen and glucose deprivation

Ethnopharmacological relevance

TongLuoJiuNao (TLJN) is an herb extract that mainly contains ginsenoside Rg1 and geniposide, which are clinically used for treating ischemic damages in the brain.

Aim of the study

In the stroke, cerebral ischemia followed by oxygen reperfusion induced apoptosis in hippocampal neurons, while extension of axons and dendrites in neurons may compensate for and repair damages of neuronal network in the hypoxia brain. In this study, we investigated whether TLJN can protect neurons against damages by ischemia in brain vasculature.

Materials and methods

We measured cell viability and lactate dehydrogenase (LDH) release from primary culture of rat hippocampal neurons before and after the neurons were deprived of oxygen and glucose (OGD). In addition, the effects were evaluated with cell viability and neurite outgrowth before or after OGD.

Results

We found that TLJN could play a neuroprotective role to cultured primary rat hippocampal neurons under both normal and oxygen/glucose-deprivation (OGD) conditions. TLJN could protect both cultured primary rat hippocampal neurons and brain microvascular endothelial cells (BMECs) from cell death under both normal and oxygen/glucose-deprivation (OGD) conditions. Moreover, under the same conditions, BMECs-conditioned media pretreated by TNJN could also promote neuron viability and neurite outgrowth, indicating that TLJN stimulated BMECs to secret some neuroprotective/neurotrophic factors.

Conclusion

These findings suggest that TLJN has a marked neuroprotective and neurotrophic roles by either direct or indirect operation, and provide insight into the mechanism of clinical efficacy of this drug against stroke.     

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway

Ethnopharmacological relevance

Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke.

Aim of the research

To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action.

Material and methods

A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0 mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism.

Results

Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN).

Conclusion

HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.     

Cerebralcare Granule,a Chinese herb compound preparation,improves cerebral microcirculatory disorder and hippocampal CA1 neuron injury in gerbils after ischemia–reperfusion

Aim of the study

Cerebralcare Granule^® (CG) is a Chinese herb compound preparation that has been used for treatment of cerebrovascular related diseases. However, the effect of post-treatment with CG on ischemia and reperfusion (I/R) induced cerebral injury is so far unclear.

Materials and methods

In present study, cerebral global I/R was induced in Mongolian gerbils by clamping bilateral carotid arteries for 30 min followed by reperfusion for 5 days, and CG (0.4 g/kg or 0.8 g/kg) was administrated 3 h after the initiation of reperfusion.

Results

Post-treatment with CG for 5 days attenuated the I/R-induced production of hydrogen peroxide in, leukocyte adhesion to, and albumin leakage from cerebral microvessels, and, meanwhile, protected neuron from death, reduced the number of caspase-3- and Bax-positive cells, and increased Bcl-2-positive cells in hippocampal CA1 region.

Conclusion

The results suggest that CG given after initiation of reperfusion is able to ameliorate cerebral microvascular dysfunction and hippocampal CA1 neuron damage caused by I/R.