Role of P2X7 receptor in colon cancer progression / 国际肿瘤学杂志

P2X7 receptor is an ion channel receptor with adenosine triphosphate (ATP) as its ligand, which is widely expressed in various immune cells and tissues. Activated P2X7 receptor is involved in a variety of physiological and pathological processes. P2X7 receptor is abnormally expressed in colon cancer, and plays a duel role of cancer-promoting and cancer-suppressing in colon cancer progression. When P2X7 receptor is activated by extracellular ATP, it can effectively inhibit proliferation and induce apoptosis of colon cancer cells through various mechanisms. In addition, P2X7 receptor can also promote the growth, invasion and metastasis of colon cancer. Understanding the activation of P2X7 receptor and its effect mechanism is of great significance for the treatment of colon cancer.

Role of P2X 7 receptor in microglia in medial prefrontal cortex in neuropathic pain in rats: relationship with autophagy / 中华麻醉学杂志

Objective:To evaluate the role of P2X 7 receptor in microglia in the medial prefrontal cortex (mPFC) in neuropathic pain (NP) and the relationship with autophagy in rats. Methods:Sixty-four healthy SPF male Sprague-Dawley rats, aged 6-8 weeks, weighing 200-250 g, were divided into 4 groups ( n=16 each) using a random number table method: sham operation group (S group), NP group, sham operation+ P2X 7 receptor blocking group (SP group), and NP+ P2X 7 receptor blocking group (NP+ P group). The NP model was established by ligation of the sciatic nerve.Fourteen days later a cannula was placed in the mPFC with a brain stereotactic instrument, P2X 7 receptor blocker A-740003 0.5 μg/0.5 μl was injected into bilateral mPFC for 3 consecutive days starting from the 14th day in SP and NP+ P groups, and DMSO 0.5 μl was injected instead of A-740003 in S and NP groups.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 3, 7 and 10 days after establishing the model and 14, 15 and 16 days after administration.Then the rats were sacrificed, and the mPFC was removed for determination of the expression of P2X 7 receptor and mRNA and autophagy-related proteins Beclin1 and LC3Ⅱ/Ⅰ (by quantitative real-time polymerase chain reaction or by Western blot) and co-expression of P2X 7R and microglia (by immunofluorescence) and the number of autophagosomes in mPFC (with a transmission electron microscope). Results:Compared with group S, MWT was significantly decreased, and TWL was shortened at 3, 7 and 10 days after establishing the model, the expression of P2X 7 receptor and mRNA, Beclin1 and LC3Ⅱ/Ⅰ was up-regulated at 30 min after administration on 16 days after establishing the model, and the number of cells co-expressing P2X 7 receptor and IBA-1 and the number of autophagosomes were increased in NP and NP+ P groups ( P<0.05), and no significant change was found in the indexes mentioned above in group SP ( P>0.05). Compared with group NP, MWT was significantly increased, and TWL was prolonged at 30 min after administration on 14, 15 and 16 days after establishing the model, the expression of P2X 7 receptor and mRNA, Beclin1 and LC3Ⅱ/Ⅰ was down-regulated, and the number of cells co-expressing P2X 7 receptor and Iba-1 and the number of autophagosome were decreased in group NP+ P ( P<0.05). Conclusion:Up-regulation of P2X 7 receptor expression in microglia in mPFC is involved in the process of NP in rats, which is associated with the promotion of autophagy.

Study on the best concentration of miRNA-22 agomir in the treatment of temporal lobe epilepsy by single injection of lateral ventricle / 中国医师杂志

Objective To investigate the optimal initial concentration of microRNA22 agomir in epilepsy model induced by lithium chloride-pilocarpine after single injection of lateral ventricle.Methods 36 rats with acute temporal lobe epilepsy were randomly divided into 6 groups:the control group and the other five groups were the experimental group.All epilepsy rats were selected for right lateral ventricle injection.The control group was given negative control reagent,while the experimental group were given 0.1 mmol/L,2.5 mmol/L,5 mmol/L,10 mmol/L,20 mmol/L different concentrations of miRNA22agomir reagent.6 rats in each group were randomly selected for acute phase experiment after 3 days of administration.The expression of P2X7 in hippocampus of epilepsy rats was determined by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR).Results Compared with control group,the protein and mRNA expression of P2X7 reduced in all of the model group.The protein and mRNA expression level of P2X7 protein in hippocampus of rats injected with 2.5 mmol/L,5 mmol/L and 10 mmol/L in each experimental group were significantly lower than that in the other two groups (P ＜ 0.05).Moreover,the protein and mRNA expression level of P2X7 were the lowest at 2.5 mmol/L injection and 10 mmol/L,and there was no significant difference between the two groups (P ＞ 0.05).Conclusions The optimal onset concentration for unilateral lateral ventricle injection miRNA22 agomir treatment of temporal lobe epilepsy is 2.5 mmol/L.

Expression of P2X7 receptor in RGC-5 cell line and selection of an effective siRNA sequence down-regulating P2X7 receptor / 中国医师杂志

Objective This study aims to investigate the gene expression of P2X7 receptor in retinal ganglion cell line (RGC-5),and to design and select the small interfering RNA (siRNA) which can specifically and effectively downregulate P2X7 receptor expression.Methods The mRNA and protein expressions of P2X7 receptor in RGC-5 cells were examined by real-time polymerase chain reaction (qRT-PCR),Western blot and Immunofluorescence,and compared with those of mouse retina and other tissues.Three P2X7 receptor-specific double stranded siRNAs (P2X7-siRNA-1-3) were designed and delivered into RGC-5 cells by riboFECTTM CP.60 hours after transfection,the expression level of P2X7 receptor was analyzed by qRT-PCR,Western blot and Immunofluorescence.Results The expression of P2X7 receptor was detected in both RGC-5 cell line and mouse retina,and the receptor was mainly expressed in the nucleus and cytoplasm of RGC-5 cells.P2X7-siRNA-3 can effectively down-regulate the mRNA and protein expression of P2X7 at the same time.Conclusions RGC-5 cell line can serve as a good model for studying the biological function of P2X7 receptor in retinal ganglion cells in vitro.We have managed to design and synthesize the siRNA pair that specifically and effectively lowering P2X7 receptor expression.The current study has laid the foundation for future investigations on treating glaucomatous retinopathy by downregulation of P2X7 receptor.

P2X7 receptor and relationship with the death of retinal neurons / 中华眼底病杂志

Retinal neuronal cells are crucial in the formation of vision.Injury or death of these cells may lead to irreversible damage to visual function due to their low regenerative capacity.The P2X7 receptor is a trimeric adenosine triphosphate (ATP)-gated cation channel.Recent studies have shown that P2X7 receptor plays a role in retinal neuronal death.In a series of animal models,when exposed to conditions of hypoxia or ischemia,elevated ocular pressure,trauma and exogenous agonists,P2X7 receptor activated by extracellular ATP can cause death of retinal neuronal cells such as retinal ganglion cells and photoreceptor cells through direct or indirect pathways.Blocking the expression and function of P2X7 receptor by its specific antagonist and gene knocking-out,the loss of retinal neuronal cells is significantly attenuated.P2X7 receptor may become a potential novel neuroprotective target for diseases related to the loss of retinal neurons.

P2X7 Receptor Expression in Coexistence of Papillary Thyroid Carcinoma with Hashimoto's Thyroiditis

BACKGROUND: This study was aimed at investigating the relation of P2X7 receptor (P2X7R) expression with the clinicopathological features of papillary thyroid carcinoma (PTC) coexisting with Hashimoto's thyroiditis (HT). METHODS: We examined 170 patients (84, PTC with HT; 86, PTC without HT). P2X7R expression was examined by immunohistochemical methods. The staining intensity and patterns were evaluated and scored using a semi-quantitative method. RESULTS: The PTC with HT group was more likely to contain women and had less extrathyroid extension, lymph node (LN) metastasis, lymphovascular invasion, and recurrence than the PTC without HT group. Patients positive for P2X7R had significantly higher frequencies of lymphovascular invasion, extrathyroid extension, LN metastasis, and absence of HT. As shown by multivariate analysis, the expression of P2X7R was significantly higher if HT was absent and extrathyroid extension was present. In the PTC with HT group, the expression of P2X7R was significantly higher in patients with tumor multifocality, lymphovascular invasion, and extrathyroid extension. In the PTC without HT group, the expression of P2X7R was significantly higher in women and those having tumor multifocality. CONCLUSIONS: Coexistence of PTC with HT is associated with good prognostic factors, and P2X7R expression in PTC was correlated with poor prognostic factors and the absence of HT.

P2X7 receptor mediates activation of microglial cells in prostate of chemically irritated rats

Purpose Evidence shows that adenosine triphosphate (ATP) is involved in the transmission of multiple chronic pain via P2X7 receptor. This study was to investigate the P2X7 and microglial cells in the chronic prostatitis pain. Materials and Methods Rats were divided into control group and chronic prostatitis group (n = 24 per group). A chronic prostatitis animal model was established by injecting complete Freund's adjuvant (CFA) to the prostate of rats, and the thermal withdrawal latency (TWL) was detected on days 0, 4, 12 and 24 (n = 6 at each time point in each group). Animals were sacrificed and the pathological examination of the prostate, detection of mRNA expression of P2X7 and ionized calcium binding adaptor molecule 1 (IBA-1) and measurement of content of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the dorsal horn of L5-S2 spinal cord were performed on days 0, 4, 12 and 24. In addition, the content of TNF-α and IL-1β in the dorsal horn of L5-S2 spinal cord was measured after intrathecal injection of inhibitors of microglial cells and/or P2X7 for 5 days. Results The chronic prostatitis was confirmed by pathological examination. The expression of P2X7 and IBA-1 and the content of TNF-α and IL-1β in rats with chronic prostatitis were significantly higher than those in the control group. On day 4, the expressions of pro-inflammatory cytokines became to increase, reaching a maximal level on day 12 and started to reduce on day 24, but remained higher than that in the control group. Following suppression of microglial cells and P2X7 receptor, the secretion of TNF-α and IL-1β was markedly reduced. Conclusion In chronic prostatitis pain, the microglial cells and P2X7 receptor are activated resulting in the increased expression of TNF-α and IL-1β in the L5-S2 spinal cord, which might attribute to the maintenance and intensification of pain in chronic prostatitis. .

Microglial P2X7 receptor expression is accompanied by neuronal damage in the cerebral cortex of the APPswe/PS1dE9 mouse model of Alzheimer's disease

The possibility that P2X7 receptor (P2X7R) expression in microglia would mediate neuronal damage via reactive oxygen species (ROS) production was examined in the APPswe/PS1dE9 mouse model of Alzheimer's disease (AD). P2X7R was predominantly expressed in CD11b-immunopositive microglia from 3 months of age before Abeta plaque formation. In addition, gp91phox, a catalytic subunit of NADPH oxidase, and ethidium fluorescence were detected in P2X7R-positive microglial cells of animals at 6 months of age, indicating that P2X7R-positive microglia could produce ROS. Postsynaptic density 95-positive dendrites showed significant damage in regions positive for P2X7R in the cerebral cortex of 6 month-old mice. Taken together, up-regulation of P2X7R activation and ROS production in microglia are parallel with Abeta increase and correlate with synaptotoxicity in AD.