Acute EPA-induced learning and memory impairment in mice is prevented by DHA.

Eicosapentaenoic acid (EPA), an omega-3 fatty acid, has been widely used to prevent cardiovascular disease (CVD) and treat brain diseases alone or in combination with docosahexaenoic acid (DHA). However, the impact of EPA and DHA supplementation on normal cognitive function and the molecular targets of EPA and DHA are still unknown. We show that acute administration of EPA impairs learning and memory and hippocampal LTP in adult and prepubescent mice. Similar deficits are duplicated by endogenously elevating EPA in the hippocampus in the transgenic fat-1 mouse. Furthermore, the damaging effects of EPA are mediated through enhancing GABAergic transmission via the 5-HT6R. Interestingly, DHA can prevent EPA-induced impairments at a ratio of EPA to DHA similar to that in marine fish oil via the 5-HT2CR. We conclude that EPA exhibits an unexpected detrimental impact on cognitive functions, suggesting that caution must be exercised in omega-3 fatty acid supplementation and the combination of EPA and DHA at a natural ratio is critical for learning and memory and synaptic plasticity.

Safety and effectiveness of a Tai Chi-based cardiac rehabilitation programme for chronic coronary syndrom patients: study protocol for a randomised controlled trial.

INTRODUCTION: Preliminary evidence from clinical observations suggests that Tai Chi exercise may offer potential benefits for patients with chronic coronary syndrom (CCS). However, the advantages for CCS patients to practice Tai Chi exercise as rehabilitation have not been rigorously tested and there is a lack of consensus on its benefits. This study aims to develop an innovative Tai Chi Cardiac Rehabilitation Program (TCCRP) for CCS patients and to assess the efficacy, safety and acceptability of the programme. METHODS AND ANALYSIS: We propose to conduct a multicentre randomised controlled clinical trial comprising of 150 participants with CCS. The patients will be randomly assigned in a 1:1 ratio into two groups. The intervention group will participate in a supervised TCCRP held three times a week for 3 months. The control group will receive supervised conventional exercise rehabilitation held three times a week for 3 months. The primary and secondary outcomes will be assessed at baseline, 1 month, 3 months after intervention and after an additional 3-month follow-up period. Primary outcome measures will include a score of 36-Item Short Form Survey and Chinese Perceived Stress Scale. The secondary outcome measures will include body composition, cardiopulmonary exercise test, respiratory muscle function, locomotor skills, echocardiogram, New York Heart Association classification, heart rate recovery time and laboratory examination. Other measures also include Seattle Angina Scale, Pittsburgh Sleep Quality Index, Patient Health Questionnaire-9, Generalized Anxiety Disorder-7 and Berg Balance Scale. All adverse events will be recorded and analysed. ETHICS AND DISSEMINATION: This study conforms to the principles of the Declaration of Helsinki and relevant ethical guidelines. Ethical approval has been obtained from the Ethics Committee of Chinese People's Libration Army General Hospital (approval number: S2019-060-02). Findings from this study will be published and presented at conferences for widespread dissemination of the results. TRIAL REGISTRATION NUMBER: NCT03936504.

An L-type calcium channel agonist, bay K8644, extends the window of intervention against ischemic neuronal injury.

Our previous data indicate that the inhibition of L-type calcium channels (LTCCs) might be the cause of post-ischemic neuronal injury and that the activation of LTCCs can give rise to neuroprotection. In the present study, we aimed to profile the intervention window of Bay K8644, an LTCC agonist, and determine the involved mechanisms. The four vessel occlusion and oxygen-glucose deprivation models were employed to mimic ischemia/reperfusion damage in vivo and in vitro. Neuronal injury was analyzed using Nissl and Fluoro-Jade B staining in vivo and Hoechst 33342 and propidium iodide staining in vitro. The behavioral effects were tested using the Morris water maze. The phosphorylation of P38, Jun N-terminal kinase, and extracellular-regulated kinase (ERK) was detected by Western blotting. Our results show that Bay K8644 administered as late as 24 h after reperfusion prevented CA1 neuronal death and ameliorated the deficiencies in spatial learning performance induced by global ischemia. In oxygen-glucose deprivation (OGD), Bay K8644 delivered from 1 to 12 h after re-oxygenation reduced neuronal death. The decrease in p-ERK1/2 that was observed at 1 h after OGD was reversed by Bay K8644, and the effect of Bay K8644 was blocked by treatment with U0126 and MEK kinase dead transfection. Moreover, similar to Bay K8644, FPL 64176, another potent LTCC agonist, extends the window of intervention against neuronal injury in an in vitro model of ischemia. In conclusion, our data suggest that opening LTCCs may be a practicable approach for stroke therapy.

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 24h 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.

Fuzi polysaccharide-1 produces antidepressant-like effects in mice.

Current antidepressants are clinically effective only after several weeks of administration. We show that Fuzi polysaccharide-1 (FPS), a new water-soluble polysaccharide isolated from Fuzi, which has been used to treat mood disorders in traditional Chinese medicine for centuries, increases the number of newborn cells in the dentate gyrus in adult mice, and most of these cells subsequently differentiate into new neurons. We also found that FPS administration reduces immobility in the forced swim test, and latency in the novelty suppressed-feeding test. Moreover, a 14-d regimen with FPS reverses avoidance behaviour and inhibition of hippocampal neurogenesis induced by chronic defeat stress. In contrast, imipramine, a well known antidepressant, reverses this avoidance behaviour only after 4 wk of continuous administration. Finally, acute treatment with FPS had no effect on brain monoamine levels in frontal cortex but significantly increases BDNF in the hippocampus, while the antidepressant effect and enhancement of cell proliferation induced by FPS administration were totally blocked by K252a, an inhibitor of trkB in a chronic social defeat depression model, suggesting that the neurogenic and antidepressant effects of FPS may involve BDNF signalling. In conclusion, our findings suggest that FPS could be developed as a putative antidepressant with a rapid onset of action.

[Strychnos alkaloids inhibit the proliferation of adult rat neuroprogenitor cells].

OBJECTIVE: To study the effects of strychnos alkaloids on the proliferation of adult rat neuroprogenitor cells. METHODS: Strychnos alkaloids free of strychnine and brucine were extracted from Strychnos nux vomica, and the effects of Strychnos alkaloids on the survival of HEK293 and PC12 cells were evaluated using MTT assay. In vitro cultured adult rat neuroprogenitor cells isolated from the hippocampus were treated with different concentrations of Strychnos alkaloids for 2 days, and the cell proliferation was assessed using BrdU incorporation assay. RESULTS: At the concentration above 0.5 mg/ml, Strychnos alkaloids produced toxic effect against HEK293 cells (P<0.0001), while for PC12 cells, Strychnos alkaloids inhibited the cell survival at the concentration as low as 5 microg/ml (P<0.0001). After 2 days of exposure to 50 microg/ml Strychnos alkaloids, the neuroprogenitor cells showed significantly decreased number of BrdU-positive cells (P<0.01), but the total cell number remained stable when compared with that of the control cells (P>0.05), whereas at the concentration of 100 microg/ml, Strychnos alkaloids produced obvious cytotoxicity against the neuroprogenitor cells. CONCLUSION: Strychnos alkaloids can significantly inhibit the proliferation of adult rat neuroprogenitor cells, and this effect is probably selective, suggesting the potential of Strychnos alkaloids as a new drug for treatment of neurocytoma.

[Progressive studies of paeoniflorin].

Paeoniflorin is one of the bioactive components of Paeonia lactiflora, a traditional Chinese herbal medicine. It is the main monoterpene glucoside isolated from the P. lactiflora in 1963. Since then, researchers have found that paeoniflorin has multifold pharmacological effects. In this review, based on the recent available papers published in PubMed and National Knowledge Infrastructure Data Base, we present the major current approaches in understanding the detection methodology, pharmacokinetics and pharmacology, and toxicology of paeoniflorin.

[Neuroprotective effects of Naoxintong against neuronal injury in hippocampal CA1 region following transient forebrain ischemia in rats].

OBJECTIVE: To examine the neuroprotective effects of Naoxintong and Zhongfenghuichunwan on neuronal injury in CA1 region of rat hippocampus following transient forebrain ischemia. METHODS: Transient rat forebrain ischemia for 15 min was induced by modified four-vessel occlusion method. The density of survived pyramidal cells (neurons per 1 mm linear length) in CA1 region of the hippocampus was measured under light microscope. RESULTS: In Naoxintong or nimodipine-treated rats, the density of survived pyramidal cells in CA1 region was significantly greater than that of saline group (P<0.05, P<0.001, respectively), but oral administration of Zhongfenghuichunwan had no obvious effect on ischemia-induced neuronal damage in CA1 region. CONCLUSION: Naoxintong can protect CA1 neurons against ischemic insult in rats.

Neuroprotective effects of Buyang Huanwu Decoction on neuronal injury in hippocampus after transient forebrain ischemia in rats.

Buyang Huanwu Decoction (BYHWD), a traditional Chinese medicine, has been developed as a drug to be used for treatment of stroke for hundreds of years. However, the underlying mechanisms remain unknown. In the present study, the effects of BYHWD on delayed neuronal death of hippocampus after transient forebrain ischemia were examined in rats. Transient forebrain ischemia in a duration of 15 min was induced with the four-vessel occlusion method. BYHWD (per 6.65 g/kg) was given orally to rats twice each day for 7 days before ischemia. In BYHWD-pretreated rats, the neuronal injury in the hippocampal CA1 region was significantly less than that of controls. Oral administration of BYHWD also markedly attenuated the number of TUNEL-positive neurons and suppressed the expression of caspase-3p20, a product of catalytically active caspase-3, in the CA1 region. Our results suggest that an inhibition of caspase-3 and apoptosis by BYHWD may partially account for its neuroprotection against ischemic injury in the hippocampal CA1 region.

Xiaoxuming decoction and stroke: a literature-based study.

Xiaoxuming decoction, an ancient traditional Chinese medical prescription for treatment of stroke, has somehow lost its clinical application since Tang Dynasty. Based on the historic record of this prescription, mechanisms of composition and clinical and experimental studies, the authors attempt to evaluate the standing of Xiaoxuming decoction as a remedy for stroke.