Recombinant human erythropoietin upregulates PPARγ through the PI3K/Akt pathway to protect neurons in rats subjected to oxidative stress.

In vitro cell experiments have suggested that recombinant human erythropoietin (rhEPO) and peroxisome proliferator activated receptor γ (PPARγ) activation exert protective effects on neurons. This study observed the learning and memory ability, antioxidant capacity and the ratio of apoptotic cells after rhEPO intervention and investigated the relationship among rhEPO, PI3K/Akt and PPARγ in the anti-neural oxidative stress injury process in vivo. The results showed that rhEPO significantly improved the learning and memory abilities of rats subjected to oxidative stress, enhanced the antioxidant capacity of cells, and reduced neuronal apoptosis. Then, the PI3K/Akt and PPARγ pathways were inhibited, and TUNEL staining were used to observe the changes in the effect of rhEPO. After the PI3K/Akt and PPARγ pathways were inhibited, the effect of rhEPO on rats subjected to oxidative stress was significantly weakened, suggesting that both the PI3K/Akt and PPARγ pathways are involved in the process by which rhEPO protects neurons. Finally, Western blotting and immunofluorescence staining were used to observe the changes in PI3K/Akt and PPARγ signalling proteins in the neurons after the rhEPO intervention and to explore the relationship among the three. The results showed that rhEPO significantly increased the levels of the p-Akt and PPARγ proteins and the level of the PPARγ protein in the nucleus, indicating that the PI3K/Akt pathway was located upstream of and regulates PPARγ. In conclusion, this study suggested that rhEPO activates the PI3K/Akt to upregulate PPARγ, enhance the cellular antioxidant capacity, and protect neurons in rats subjected to oxidative stress.

Downregulation of ELAVL1 attenuates ferroptosis-induced neuronal impairment in rats with cerebral ischemia/reperfusion via reducing DNMT3B-dependent PINK1 methylation.

BACKGROUND: Ferroptosis is a non-apoptotic form of programmed cell death and has been found in ischemic stroke. Increasing evidence revealed that ELAVL1 is associated with ferroptosis, but it remains largely unclear whether ELAVL1 is involved in ischemic stroke. Here, we aimed to investigate the biological role and mechanism of ELAVL1 in cerebral ischemia/reperfusion (I/R) injury. METHODS: ELAVL1 shRNA were intravenously injected into rat brain, and then ischemic/reperfusion (I/R) model was constructed in rats to detect infarct volume, neurobehavioral deficit, and several ferroptosis factors (GSH, GPX4, SLC7A11, MDA, ROS, iron ion) in vivo. Oxygen-glucose deprivation/reperfusion (OGD/R) treated pheochromocytoma-12 (PC12) cells were used as in vitro models of I/R. RIP, biotin pull-down and ChIP assays was used to explore the relationship among ELAVL1, DNMT3B, and PINK1. RESULTS: ELAVL1 was highly expressed in rat brain tissue after I/R injury. Compared with those in the I/R group, the injection of RSL3 (30 mg/kg) or ferrostatin-1 (10 mg/kg) aggravated or alleviated infarct volume, neurobehavioral impairments, and increased or decreased ferroptosis factor levels, respectively. ELAVL1 silencing ameliorated brain damage in I/R-treated rats by inhibiting ferroptosis. Moreover, ELAVL1 silencing observably facilitated cell viability, GSH content, GPX4 and SLC7A11 expression, and reduced iron ion concentration, ROS and MDA levels in OGD/R-treated PC12 cells. ELAVL1 bound with DNMT3B mRNA 3'UTR and promoted DNMT3B expression. ELAVL1 inhibited PINK1 expression through stabilizing DNMT3B mRNA and blocking DNMT3B-mediated DNA methylation of PINK1 promoter. PINK1 knockdown reversed the effects of ELAVL1 inhibition on cell viability, GSH, GPX4, SLC7A11, iron ion concentration, ROS and MDA levels in OGD/R-treated PC12 cells. CONCLUSION: ELAVL1 plays a critical role in protecting against ferroptosis-induced cerebral I/R and subsequent brain damage via DNMT3B/PINK1 axis, thus providing a new potential target for ischemic stroke treatment.

Inhibition of SNK-SPAR signaling pathway promotes the restoration of motor function in a rat model of ischemic stroke.

This study aimed to investigate the effects of SPAR signaling pathway on the restoration of motor function in ischemic stroke (IS). Sprague-Dawley male rats were separated into the control and sham groups, as well as the group for middle cerebral artery occlusion (MCAO) model establishment. Successfully established rat ischemic models were randomly divided into model, SNKMCAO-del and pcDNA3.1-SNK groups. The evaluation of motor function among the rats in each group was assessed using a balance beam, a screen test and the Garcia scoring method. CatWalk gait analysis was employed to evaluate the effect of the SNK signaling pathway on rat motor function. Triphenyltetrazolium chloride (TTC) and TUNEL staining were techniques were utilized for cerebral infarction (CI) area as well for hippocampal neuron apoptosis. The quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting methods were performed to detect mRNA and protein expressions of SNK and SPAR. When compared with the model group, the SNKMCAO-del group displayed decreased motor function score and CI area, while contrasting results were observed in the pcDNA3.1-SNK group. According to the results obtained from the CatWalk gait analysis, the SNKMCAO-del group showed a clear improvement compared to the model group whereas the pcDNA3.1-SNK group exhibited poorer results than the model group in the objective parameters of the study, such as movement, speed, running duration, print area, maximal contact area, maximal, mean intensity, and stride length. These findings suggested that SNK gene silencing promotes motor function by inhibiting the SNK-SPAR signaling pathway in rats with ischemic stroke.

Phylogenetic analysis of IDD gene family and characterization of its expression in response to flower induction in Malus.

Although INDETERMINATE DOMAIN (IDD) genes encoding specific plant transcription factors have important roles in plant growth and development, little is known about apple IDD (MdIDD) genes and their potential functions in the flower induction. In this study, we identified 20 putative IDD genes in apple and named them according to their chromosomal locations. All identified MdIDD genes shared a conserved IDD domain. A phylogenetic analysis separated MdIDDs and other plant IDD genes into four groups. Bioinformatic analysis of chemical characteristics, gene structure, and prediction of protein-protein interactions demonstrated the functional and structural diversity of MdIDD genes. To further uncover their potential functions, we performed analysis of tandem, synteny, and gene duplications, which indicated several paired homologs of IDD genes between apple and Arabidopsis. Additionally, genome duplications also promoted the expansion and evolution of the MdIDD genes. Quantitative real-time PCR revealed that all the MdIDD genes showed distinct expression levels in five different tissues (stems, leaves, buds, flowers, and fruits). Furthermore, the expression levels of candidate MdIDD genes were also investigated in response to various circumstances, including GA treatment (decreased the flowering rate), sugar treatment (increased the flowering rate), alternate-bearing conditions, and two varieties with different-flowering intensities. Parts of them were affected by exogenous treatments and showed different expression patterns. Additionally, changes in response to alternate-bearing and different-flowering varieties of apple trees indicated that they were also responsive to flower induction. Taken together, our comprehensive analysis provided valuable information for further analysis of IDD genes aiming at flower induction.

Angiotensin II and its receptor in activated microglia enhanced neuronal loss and cognitive impairment following pilocarpine-induced status epilepticus.

Neuroinflammation plays a role in the pathology of epilepsy and in cognitive impairment. Angiotensin II (AII) and the angiotensin receptor type 1 (AT1) have been shown to regulate seizure susceptibility in different models of epilepsy. Inhibition of AT1 attenuates neuroinflammatory responses in different neurological diseases. In the present study, we showed that the protein expression of AII and AT1 was increased in activated microglia following lithium pilocarpine-induced status epilepticus (SE) in rats. Furthermore, the AT1 receptor antagonist, losartan, significantly inhibited SE-induced cognitive impairment and microglia-mediated inflammation. Losartan also prevented SE induced neuronal loss in the hippocampus and exerted neuroprotection. These data suggest that losartan improves SE-induced cognitive impairment by suppressing microglia mediated inflammatory responses and attenuating hippocampal neuronal loss. Overall, our findings provide a possible therapeutic strategy for the treatment of cognitive impairment in epilepsy.

Exosome from chaperone-rich cell lysates-loaded dendritic cells produced by CELLine 1000 culture system exhibits potent immune activity.

Dendritic cells (DCs) pulsed with exosomes can stimulate efficient cytotoxic T-lymphocyte responses and anti-tumor immunity. However, the quantity of DC-derived exosomes (DCex) obtained from various culture systems is very low, which is a significant practical issue hampering progress in this research area and needs to be addressed. Gliomas were particularly aggressive, with high morbidity and mortality, indicating that this is a form of incurable highly malignant tumor of the brain with poor prognosis. In the present study, we demonstrate that the CELLine 1000 culture system can dramatically increase the production of DCex. The morphology, phenotype and immune molecules of these DCex were found to be identical to those using traditional methods. Our researches supply a cost-effective, useful method for significantly increasing the quantity of exosomes. In addition, GL261 glioma cells were chosen to separate chaperone-rich cell lysates (CRCL). The results indicate that CRCL-GL261 cell lysates can trigger the most intense expression of immune molecules on DCex or DCs, which has important implications for the research into tumor treatment and diagnosis.

Diagnostic accuracy of intracellular mycobacterium tuberculosis detection for tuberculous meningitis.

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.

[The effect of edaravone on MAPKs signal pathway associated with Abeta(25-35) treatment in PC12 cells].

OBJECTIVE: To explore whether edaravone protects cells damage via mitogen-activated protein kinases (MAPKs) signal pathway, and which procedure of p38 be affected so as to add theories for AD pathogenesis and treatments. METHODS: According to different drugs treated, PC12 cells in vitro were divided into four groups. Negative control group: cells were treated with media alone. AD model group: cells were treated with 30 pmol/L Abeta(25-35). Inhibitor control group: cells were treated with 10 micromol/L SB203580 Cp38 mitogen-activated protein kinase (p38) inhibitor], 10 micromol/L SP600125 [c-Jun NH2 terminal kinase (JNK) inhibitor], or 10 micromol/L PD98059 extracelular signal regulated kinase (ERK) inhibitor]. Low-dose, middle-dose and high-dose edaravone group: cells plated for 24 hours treated with 30 micromol/L Abeta(25-35) and co-treated with 20, 40, 80 micromol/L edaravone 3 hours, respectively. The morphology of the treated cells were observed, the p-p38, p-JNK and p-ERK proteins in each group were tested by the Western blot. The p38 mRNA were tested in each group above (only add SB203580 10 micromol/L in third group) by the real time PCR. RESULTS: (1) The p-p38 protein was significantly increased in model control group compared with that in negative control group (P<0.05). The p-p38 protein in the inhibitor group and edaravone groups was decreased significantly (P<0.05) when compared with that in model control group. The p-p38 proteins were significantly increased in the three edaravone groups compared with that in inhibiter control group (P<0.05). The p-p38 protein in middle-dose edaravone group was decreased compared with that in low-dose edaravone group (P<0.05). There was no relationship in dose-dependent manner about edaravone. Compared with three edaravone groups, the p-p38 protein was lower than it in high-dose edaravone & inhibiter group (P<0.05). (2) The p-JNK protein was significantly increased in model control group compared with that in negative control group (P<0.05). The p-JNK protein in the inhibitor group was decreased compared with that in model control group (P<0.05). (3) No significantly difference of p-ERK protein concentration was observed in other groups when compared with that in negative control group (P>0.05 each). (4) Compared with negative control group, the p38 mRNA in model control group was significantly increased, and it was significantly decreased in inhibitor control group (P<0.05 each). In 40 micromol/L and 80 micromol/L edaravone groups, the p38 mRNA was significantly decreased compared with that in model control group, and it still was decreased compared with that in inhibitor control group (P<0.05). The p38 mRNA in 40 micromol/L edaravone group was the lowest among three edaravone groups, and it was obviously different from that in 20 micromol/L and 80 micromol/L edaravone groups (P<0.05). CONCLUSION: Abeta(25-35) could increase the p-p38 and p-JNK protein expression in cultured PC12 cells, but there was no obviously expression of p-ERK protein. These indicated that Abeta(25-35) might activate MAPKs signal pathway, especially p38 and JNK, and lead to PC12 cell damage. Edaravone could decrease p38 mRNA induced-Abeta(25-35), which indicated edaravone could protect PC12 cell damage via blocking p38 signal pathway in mRNA stage and protein stage simultaneously. Hence, it is promising that edaravone would be a new medicine for AD.

[Changes in CD40 expression in the pallium and hippocampus in epileptic rats].

OBJECTIVE: To investigate the expression of inflammatory molecule CD40 in the pallium and hippocampus of rats after status epilepticus (SE).
 METHODS: The expression of CD40 in the pallium, the different areas of hippocampus and the different cells from the lithium-pilocarpine epileptic rats at different time points were examined by immunohistochemistry and double-immunofluorescent labeling.
 RESULTS: After SE, CD40 expression was obviously inhibited, especially in hippocampus. CD40 was mainly expressed in the activated microglia. CD40 positive cells reached a peak at the 3rd day and returned to a slightly higher level at the 7th day after SE compared with the level before SE.
 CONCLUSION: Elevation of CD40 expression in the activated microglia can promote inflammatory injury of rat's hippocampus, suggesting that CD40 induced-signal pathway is involved in inflammatory injury in the hippocampus after SE.

[Expression of vascular endothelial growth factor and microvessel density in different brain regions in aged rats].

OBJECTIVE: To observe the distribution of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in different brain regions in aged rats and determine the role of VEGF and MVD in the aging process of the nervous system. METHODS: We observed the expression of VEGF and MVD in different parts of rat brain in the 3- month group and 30-month group with immunohistochemical technique. RESULTS: Compared with the 3-month group, the 30-month group showed fewer VEGF-positive cells and MVD in the brain (P<0.01), and the number varied significantly in different brain regions (P<0.01). The motor cortex region contained more VEGF-positive cells and MVD than the hippocampus and cerebellum. CONCLUSION: VEGF-positive cells and MVD are decreased in every brain region of aged rats, and the motor cortex region contains more positive cells, suggesting exogenous VEGF may enhance the formation of microvessels and delay the aging of the nervous system.

Host-microbiota interaction in intestinal stem cell homeostasis.

Intestinal stem cells (ISCs) play a pivotal role in gut physiology by governing intestinal epithelium renewal through the precise regulation of proliferation and differentiation. The gut microbiota interacts closely with the epithelium through myriad of actions, including immune and metabolic interactions, which translate into tight connections between microbial activity and ISC function. Given the diverse functions of the gut microbiota in affecting the metabolism of macronutrients and micronutrients, dietary nutrients exert pronounced effects on host-microbiota interactions and, consequently, the ISC fate. Therefore, understanding the intricate host-microbiota interaction in regulating ISC homeostasis is imperative for improving gut health. Here, we review recent advances in understanding host-microbiota immune and metabolic interactions that shape ISC function, such as the role of pattern-recognition receptors and microbial metabolites, including lactate and indole metabolites. Additionally, the diverse regulatory effects of the microbiota on dietary nutrients, including proteins, carbohydrates, vitamins, and minerals (e.g. iron and zinc), are thoroughly explored in relation to their impact on ISCs. Thus, we highlight the multifaceted mechanisms governing host-microbiota interactions in ISC homeostasis. Insights gained from this review provide strategies for the development of dietary or microbiota-based interventions to foster gut health.

Breed-Driven Microbiome Heterogeneity Regulates Intestinal Stem Cell Proliferation via Lactobacillus-Lactate-GPR81 Signaling.

Genetically lean and obese individuals have distinct intestinal microbiota and function. However, the underlying mechanisms of the microbiome heterogeneity and its regulation on epithelial function such as intestinal stem cell (ISC) fate remain unclear. Employing pigs of genetically distinct breeds (obese Meishan and lean Yorkshire), this study reveals transcriptome-wide variations in microbial ecology of the jejunum, characterized by enrichment of active Lactobacillus species, notably the predominant Lactobacillus amylovorus (L. amylovorus), and lactate metabolism network in obese breeds. The L. amylovorus-dominant heterogeneity is paralleled with epithelial functionality difference as reflected by highly expressed GPR81, more proliferative ISCs and activated Wnt/ß-catenin signaling. Experiments using in-house developed porcine jejunal organoids prove that live L. amylovorus and its metabolite lactate promote intestinal organoid growth. Mechanistically, L. amylovorus and lactate activate Wnt/ß-catenin signaling in a GPR81-dependent manner to promote ISC-mediated epithelial proliferation. However, heat-killed L. amylovorus fail to cause these changes. These findings uncover a previously underrepresented role of L. amylovorus in regulating jejunal stem cells via Lactobacillus-lactate-GPR81 axis, a key mechanism bridging breed-driven intestinal microbiome heterogeneity with ISC fate. Thus, results from this study provide new insights into the role of gut microbiome and stem cell interactions in maintaining intestinal homeostasis.

A hydrolyzed casein diet promotes Ngn3 controlling enteroendocrine cell differentiation to increase gastrointestinal motility in mice.

Gut hormones are produced by enteroendocrine cells (EECs) found along the intestinal epithelium, and these cells play a crucial role in regulating intestinal function, nutrient absorption and food intake. A hydrolyzed casein diet has been reported to promote the secretion of gut hormones through the regulation of EEC development, but the underlying mechanism remains unclear. Therefore, this study was conducted to investigate whether the hydrolyzed casein diet can regulate EEC differentiation by employing mouse and organoid models. Mice were fed diets containing either casein (casein group) or hydrolyzed casein (hydrolyzed casein group) as the sole protein source. The hydrolyzed casein diet upregulated the expression of transcription factors, induced EEC differentiation, increased fasting serum ghrelin concentrations and promoted gastrointestinal (GI) motility in the duodenum compared to the casein diet. Interestingly, these differences could be abolished when there is addition of antibiotics to the drinking water, suggesting a significant role of gut microbiota in the hydrolyzed casein-mediated EEC function. Further investigation showed that the hydrolyzed casein diet led to reduced microbial diversity, especially the abundance of Akkermansia muciniphila (A. muciniphila) on the duodenal mucosa. In contrast, gavage with A. muciniphila impaired EEC differentiation through attenuated neurog3 transcription factor (Ngn3) expression, mediated through the promotion of Notch signaling. Moreover, pasteurized A. muciniphila showed similar effects to enter organoids in vitro. Overall, we found that a hydrolyzed casein diet reduced the abundance of A. muciniphila and promoted Ngn3 controlling EEC differentiation and this pathway is associated with increased GI motility in mice. The findings provide new insights into the role of hydrolyzed casein in gut transit and guidelines for using hydrolyzed casein in safe formula milk.

[Progress on neuroprotective effects of erythropoietin].

The function of erythropoietin (EPO) is recognized as a stimulator for proliferation of red blood cell (RBC), however,recent studies have showed that EPO and EPO-R are widely distributed in nervous system, which indicates that it may also have important functions in nervous system. Studies proved its neuroprotective effects, especially in ischemic-hypoxic nerve tissues. These effects are mainly activated through several signal transduction pathway downstream and multiple mechanisms are involved. As a neuroprotective factor, EPO has been investigated in the clinical studies, which may lead to the clinical application in the future.

USP22 knockdown protects against cerebral ischemia/reperfusion injury via destabilizing PTEN protein and activating the mTOR/TFEB pathway.

Ubiquitin-specific protease 22 (USP22) expression was reported to be increased in response to ischemic brain damage, but the biological role and underlying mechanism remain little understood. USP22 shRNA was intravenously injected into the mouse brain, and then a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model was constructed, and the infarct volume, neurobehavioral deficit score, cell apoptosis, oxidative stress, and autophagy in vivo were evaluated. Oxygen-glucose deprivation/reperfusion (OGD/R) treated pheochromocytoma-12 (PC12) cells were used as an in vitro model of ischemia/reperfusion. The effects of USP22 on proliferation, apoptosis, oxidative stress, and autophagy were explored by CCK-8, flow cytometry, ELISA, and Western blot assays. The relationship between USP22 and the phosphatase and tensin homolog (PTEN) was measured by Co-IP and Western blot assays. Both USP22 and PTEN were highly expressed in MCAO/R mouse brain tissues and OGD/R-induced PC12 cells. In vitro, USP22 knockdown strongly improved OGD/R-mediated changes in cell viability, apoptosis, oxidative stress, and lactate dehydrogenase (LDH) production in PC12 cells. USP22 bound to PTEN and stabilized PTEN expression by decreasing its ubiquitination. PTEN overexpression reversed the promoting effect of USP22 knockdown on cell viability and the inhibitory effects of USP22 knockdown on apoptosis, oxidative stress, and LDH release rate in PC12 cells subjected to OGD/R. PTEN silencing elevated the protein levels of p62, p-mTOR, TFEB, and LAMP1 and reduced the protein levels of LC3-II/LC3-I. USP22 expression levels were negatively correlated with mTOR expression levels, and USP22-shRNA-mediated expression of p62, p-mTOR, TFEB, and LAMP1 was reversed by rapamycin, an inhibitor of mTOR. In vivo, USP22 silencing significantly alleviated infarct volume, neurobehavioral impairments, cell apoptosis, oxidative stress, and autophagy in MCAO/R mice. USP22 knockdown exerts neuroprotective effects in cerebral ischemia/reperfusion injury by downregulating PTEN and activating the mTOR/TFEB pathway.

[Association of Helicobacter pylori infection and serum homocysteine level in patients with cerebral infarction].

OBJECTIVE: To investigate the association of Helicobacter pylori infection and serum homocysteine(Hcy) levels with acute cerebral infarction. METHODS: Serum Hp-IgG, Hp-CagA-IgG and Hcy were detected by biological micro-array analysis system in 85 patients with acute cerebral infarction and 40 healthy subjects (control group). RESULTS: The positive rates of Hp-IgG and Hp-CagA-IgG significantly increased in cerebral infarction group compared with controls (P<0.05). There were significant differences in serum Hcy level between Hp-CagA-IgG positive and negative patients (P<0.05), but not between Hp-IgG positive and negative patients (P>0.05). CONCLUSION: CagA-positive Hp infection may increase the risk of cerebral infarction, which might be associated with the increased serum homocysteine level.

[Characteristic of microglial activation of hippocampus in experimental epileptic rats].

OBJECTIVE: To investigate the characteristics of microglial activation of hippocampus in experimental epileptic rats. METHODS: Morphological changes and proliferation of OX-42 positive cells were compared at different time points after status of epilepticus (SE) in lithium-pilocarpine induced epileptic rats. RESULTS: OX-42 positive cells were activated after SE, which increased to a peak at 3-7 d and in a relatively stable state at 7-14 d; then gradually decreased after 14d and returned to slightly higher level than previously at 21 d. CONCLUSION: Inflammatory injury, microglial activation and cell proliferation are closely related after seizures, microglial activation may be an important mechanism in the inflammatory injury of epilepsy.

[Effect of Helicobacter pylori infection on platelet activation and coagulation function in patients with acute cerebral infarction].

OBJECTIVE: To investigate the effect of Helicobacter pylori (Hp) on platelet activation and coagulation function in patients with acute cerebral infarction. METHODS: Sixty-six patients with acute cerebral infarction and 50 health individuals were enrolled in the study. Hp antibody,expression of CD62p on platelets and clotting indexes were measured and compared between two groups. RESULTS: The positive rate of Hp-IgG and Hp-CagA in cerebral infarction patients were higher than that in controls (P<0.05). The positive rate of CD62p in patients with positive Hp-IgG and Hp-CagA was significantly higher than that in negative patients and also controls (P<0.05). The APTT and TT were lower and FIB was higher in patients with positive Hp antibody than those in patients with negative Hp antibody (P<0.05),but there was no difference in PT,PTR and INR (P>0.05). CONCLUSION: Hp infection can activate platelets and affect coagulation function,which may be involved in the development of cerebral infarction.

[The anti-aging effect of EPO and the preliminary probe into its mechanisms].

OBJECTIVE: To study whether erythropoietin ( EPO) has the anti-aging effect and the mechanisms of how it effects. METHODS: 5% D-galactose hypodermic injection for 6 weeks to establish the aging model. Divided rats into 5 groups randomly: the normal control (group A), the aging model (group B), the low dosage (1 000 U/ (kg x d)) of recombinant human erythropoietin (rhEPO) intervene (group C), the middle dosage (3 000 U/(kg x d)) of rhEPO intervene (group D) and the high dosage (5 000 U/(kg x d)) of rhEPO intervene (group E), 10 rats in each group. Morris water maze was used to comparing the behavioral indexes. After decapitating the rats, the malonaldehyde (MDA), Na(+)-K+ ATPase, total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) of brain tissue were tested. One rat from each group was selected randomly to observe the hippocampal ultramicrostructure. RESULTS: (1) Compared with group A, the learning and memory ability of group B reduced, the level of MDA, the Na(+)-K+ ATPase, T-AOC and the SOD activities of brain tissue decreased (P < 0.05), besides, a series of aging changes were observed in the hippocampal ultramicro-structure in group B. (2) Compared with group B, an improved learning and memory ability of group D, a reduced MDA content and an increased activity of Na(+)-K+ ATPase, T-AOC and the SOD activities of brain tissue in group D were also observed with a improved hippocampal ultramicro-structure. (3) The low dosage of rhEPO intervention could against the decrease of the activities of brain Na(+)-K+ ATPase, SOD of aging rat (P < 0.05), but had no significant effects on the rest of the indicators. The high dosage of rhEPO intervention had no significant improvements on various indicators of aging rats in high dosage of rhEPO intervention group was noticed (P > 0.05). CONCLUSION: The middle dosage of EPO has the anti-aging effect, and its mechanisms may be related to enhancing the antioxidant enzymes activity and increasing the antioxidant capacity.

Recombinant human erythropoietin protects long-term cultured ageing primary nerve cells by upregulating the PI3K/Akt pathway.

OBJECTIVE: Previous studies have found that recombinant human erythropoietin (rhEPO) protects long-term cultured ageing primary nerve cells by enhancing the endogenous antioxidant capacity of cells; however, its signalling pathways are not clear. This study aimed to explore the relationship between the rhEPO and PI3K/Akt pathways in the protection of senescent nerve cells at the cellular level. METHODS: Primary nerve cells were cultured for 22 days to mimic the natural ageing process of nerve cells. rhEPO and LY294002 were administered as an intervention on the 11th day of culture. Western blot, immunochemistry, 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide, immunofluorescence double-labelling staining, Annexin V-FITC/PI double-labelling flow cytometry, and SA-ß-gal staining experiments were used to observe the expression levels of erythropoietin receptor (EPOR) and phosphorylated Akt (p-Akt) protein and the related indices of nerve cell senescence. RESULTS: Western blot experiments showed that in ageing long-term cultured primary neurons, the EPOR and p-Akt decreased and rhEPO upregulated the expression levels of EPOR and p-Akt protein. The rest showed that the PI3K/Akt pathway blockade reduced the antioxidation capacity, cell viability, cell morphology, and ratio of apoptotic cells and senescent cells of rhEPO on ageing long-term cultured primary nerve cells. CONCLUSIONS: This study explored the relationship between the rhEPO and PI3K/Akt pathways in the protection of ageing nerve cells at the cellular level and found that rhEPO protects long-term cultured ageing primary nerve cells by upregulating the PI3K/Akt pathway. These findings provide a theoretical basis and experimental evidence for the antiaeging mechanism of EPO in the nervous system.