Down-regulation of miR-140-3p can alleviate neonatal repetitive pain in rats via inhibiting TGF-β3

Glucose attenuates the long-term adverse neurodevelopment effect of neonate pain stimulus via CRF/GR in rats

BACKGROUND

Neonates undergo numerous painful procedures throughout their hospitalization. Repeated procedural pain may cause adverse long-term effects. Glucose as a non-pharmacological analgesia, is used for neonate pain management. In this study, potential mechanism of attenuate pain induced by glucose in neurodevelopment effect of neonate pain stimulus was investigated.

METHODS

Neonatal rats to perform a repetitive injury model and glucose intervention model in the postnatal day 0-7(P0-7). Pain thresholds were measured by von Frey test weekly. The puberty behavioral outcome, tissue loss and protein expression in hippocampus were analyzed.

RESULTS

Oral administration of glucose after repeated pain stimulation can maintain the hippocampal structure in, and reduce the expressions of corticotropin releasing factor (CFR) and glucocorticoid receptor (GR), therefore, resulted in long-term threshold of pain and cognitive improvement.

CONCLUSION

Exposure to neonatal repeated procedural pain causes persistent mechanical hypersensitivity and the dysfunction of spatial memory retention at puberty. In addition, glucose can relieve these adverse effects, possibly via decreasing CRF/GR levels to change the hypothalamus-pituitary-adrenal (HPA) axis.

miR-22-3p in the rostral ventrolateral medulla promotes hypertension through inhibiting β-arrestin-1

It has been documented that increased sympathetic activity contributes to the development of cardiovascular diseases, such as hypertension. We previously reported that β-arrestin-1, a multifunctional cytoskeletal protein, was downregulated in the rostral ventrolateral medulla (RVLM) of the spontaneously hypertensive rat (SHR), and its overexpression elicited an inhibitory effect on sympathetic activity in hypertension. microRNA (miR)-22-3p has been reported to be associated with the pathological progress of hypertension. The purpose of this study was to determine the role of miR-22-3p in β-arrestin-1-mediated central cardiovascular regulation in hypertension. It was observed that miR-22-3p was upregulated in the RVLM of SHRs compared with normotensive Wistar-Kyoto (WKY) rats, and it was subsequently confirmed to target the β-arrestin-1 gene using a dual-luciferase reporter assay. miR-22-3p was downregulated in the RVLM using adeno-associated virus with 'tough decoys', which caused a significant increase of β-arrestin-1 expression and decrease of noradrenaline and blood pressure (BP) in SHRs. However, upregulation of miR-22-3p using lentivirus in the RVLM of WKY rats significantly increased BP. In in vitro PC12 cells, enhanced oxidative stress activity induced by angiotensin II was counteracted by pretreatment with miR-22-3p inhibitor, and this effect could be abolished by β-arrestin-1 gene knockdown. Furthermore, microglia exhaustion significantly diminished miR-22-3p expression, and enhanced β-arrestin-1 expression in the RVLM of SHRs. Activation of BV2 cells in vitro evoked a significant increase of miR-22-3p expression, and this BV2 cell culture medium was also able to facilitate miR-22-3p expression in PC12 cells. Collectively, our findings support a critical role for microglia-derived miR-22-3p in inhibiting β-arrestin-1 in the RVLM, which is involved in central cardiovascular regulation in hypertension. KEY POINTS: Impairment of β-arrestin-1 function in the rostral ventrolateral medulla (RVLM) has been reported to be associated with the development of sympathetic overactivity in hypertension. However, little is known about the potential mechanisms of β-arrestin-1 dysfunction in hypertension. miR-22-3p is implicated in multiple biological processes, but the role of miR-22-3p in central regulation of cardiovascular activity in hypertension remains unknown. We predicted that miR-22-3p could directly bind to the β-arrestin-1 gene (Arrb1), and this hypothesis was confirmed by using a dual-luciferase reporter assay. Inhibition of β-arrestin-1 by miR-22-3p was further verified in both in vivo and in vitro experiments. Furthermore, our results suggested miR-22-3p as a risk factor for oxidative stress in the RVLM, thus contributing to sympatho-excitation and hypertension. Our present study provides evidence that microglia-derived miR-22-3p may underlie the pathogenesis and progression of neuronal hypertension by inhibiting β-arrestin-1 in the RVLM.

Orientin Reduces the Effects of Repeated Procedural Neonatal Pain in Adulthood: Network Pharmacology Analysis, Molecular Docking Analysis, and Experimental Validation

Background

Premature infants often undergo painful procedures and consequently experience repeated procedural neonatal pain. This can elicit hyperalgesia and cognitive impairment in adulthood. Treatments for neonatal pain are limited. Orientin is a flavonoid C-glycoside that has repeatedly been shown to have pharmacological effects in the past decades. The aim of this study was to systematically explore the effect of orientin on repeated procedural neonatal pain using network pharmacology, molecular docking analysis, and experimental validation.

Methods

Several compound-protein databases and disease-protein databases were employed to identify proteins that were both predicted targets of orientin and involved in neonatal pain. A protein-protein interaction (PPI) network was constructed, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore the potential mechanism of action. Molecular docking analysis was employed to calculate the binding energy and visualize the interactions between orientin and potential target proteins. Finally, a mouse model of repeated procedural neonatal pain was established and orientin was administered for 6 days. The mechanical and thermal pain thresholds were assessed in neonates and adult mice. A Morris water maze was employed to investigate cognitive impairment in adult mice.

Results

A total of 286 proteins that were both predicted targets of orientin and involved in neonatal pain were identified. The hub proteins were SRC, HSP90AA1, MAPK1, RHOA, EGFR, AKT1, PTPN11, ESR1, RXRA, and HRAS. GO analysis indicated that the primary biological process (BP), molecular function (MF), and cellular component (CC) were protein phosphorylation, protein kinase activity, and vesicle lumen, respectively. KEGG analysis revealed that the mitogen-activated protein kinase (MAPK) signaling pathway may be the key to the mechanism of action. Molecular docking analysis showed the high binding affinities of orientin for MAPK1, MAPK8, and MAPK14. In mice, orientin inhibited the hyperalgesia in the pain threshold tests in neonates and adult mice and cognitive impairment in adult mice. Immunofluorescence showed that phosphorylated MAPK1 (p-ERK) protein levels in the hippocampus and spinal dorsal horn were downregulated by orientin.

Conclusion

The findings suggested that orientin alleviates neonatal pain, and the MAPK signaling pathway is involved.

Dexmedetomidine attenuates neuroinflammation and microglia activation in LPS-stimulated BV2 microglia cells through targeting circ-Shank3/miR-140-3p/TLR4 axis

It has been shown that dexmedetomidine (Dex) could attenuate postoperative cognitive dysfunction (POCD) via targeting circular RNAs (circRNAs). Circ-Shank3 has been found to be involved in the neuroprotective effects of Dex against POCD. However, the role of circ-Shank3 in POCD remains largely unknown. Reverse transcription quantitative PCR (RT-qPCR) was performed to detect circ-Shank3 and miR-140-3p levels in lipopolysaccharide (LPS)-treated microglia BV-2 cells in the absence or presence of Dex. The relationship among circ-Shank3, miR-140-3p and TLR4 was confirmed by dual-luciferase reporter assay. Additionally, Western blot and immunofluorescence (IF) assays were conducted to evaluate TLR4, p65 and Iba-1 or CD11b levels in cells. In this study, we found that Dex notably decreased circ-Shank3 and TLR4 levels and elevated miR-140-3p level in LPS-treated BV2 cells. Mechanistically, circ-Shank3 harbor miR-140-3p, functioning as a miRNA sponge, and then miR-140-3p targeted the 3'-UTR of TLR4. Additionally, Dex treatment significantly reduced TLR4 level and phosphorylation of p65, and decreased the expressions of microglia markers Iba-1 and CD11b in LPS-treated BV2 cells. As expected, silenced circ-Shank3 further reduced TLR4, p65 and Iba-1 and CD11b levels in LPS-treated BV2 cells in the presence of Dex, whereas these phenomena were reversed by miR-140-3p inhibitor. Collectively, our results found that Dex could attenuate the neuroinflammation and microglia activation in BV2 cells exposed to LPS via targeting circ-Shank3/miR-140-3p/TLR4 axis. Our results might shed a new light on the mechanism of Dex for the treatment of POCD.

Propofol alleviates neuropathic pain in chronic constriction injury rat models via the microRNA-140-3p/Jagged-1 peptide/Notch signaling pathway

Chronic constriction injury (CCI) of the sciatic nerve was used to establish neuropathic pain (NP) models in rats. CCI rats were then treated with propofol (Pro) and their paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) were measured. In addition, the expression patterns of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-10 were detected. CCI rats treated with propofol were further injected with antagomiR-140-3p to verify the role of miR-140-3p in propofol's analgesic actions. In addition to confirming the relationship between miR-140-3p and JAG1, the expression patterns of JAG1 itself were detected. Propofol-treated CCI rats were also injected with Ad-JAG1 (adenovirus-packaged JAG1 overexpression vector and Ad-NC) to test the role of JAG1 in propofol's analgesic mechanism of action. Finally, the levels of JAG1 and Notch pathway-related proteins were detected RESULTS: Propofol was found to alleviate NP, including thermal hyperalgesia and mechanical pain threshold. Propofol could also ameliorate neuroinflammation by up-regulating the expression of IL-10 and inhibiting the release of TNF-α and IL-1β. Mechanically, propofol enhanced the amount of miR-140-3p in CCI rats via the regulation of JAG1. Down-regulation of miR-140-3p, or up-regulation of JAG1, could reduce the protective effect of propofol against NP. Propofol inhibited the activation of Notch signaling via miR-140-3p/JAG1 to realize its analgesic effect CONCLUSION: Our findings indicated that propofol inhibits inflammatory responses and the Notch signaling pathway via miR-140-3p/JAG1 to alleviate NP. These data provide evidence to support a potential clinical therapy for NP.

KCNQ1OT1 Exacerbates Ischemia-Reperfusion Injury Through Targeted Inhibition of miR-140-3P

Potassium voltage-gated channel subfamily Q member 1 opposite strand 1 (KCNQ1OT1), a long non-coding RNA found in the KCNQ1 locus, has been evidenced to play important roles in the aggravation of inflammatory and oxidative stresses under hypoxia, but whether and how KCNQ1OT1 contributes to neuronal damages in the cerebral ischemic stroke remains unknown. In the present study, we found a dominant upregulation of KCNQ1OT1 both in the plasma of cerebral ischemia patients and in an oxygen-glucose deprivation and reperfusion (OGD/R) model in PC12 cells. KCNQ1OT1 knocking-down significantly ameliorated the inflammation, oxidative stress, and cell apoptosis induced by OGD/R. We further demonstrated that KCNQ1OT1 directly bound to and suppressed the expression of miR-140-3p. Overexpressing miR-140-3p significantly alleviated both the inflammation, oxidative stress, and cell apoptosis in OGD/R, while all those cytoprotective effects of miR-140-3p-overexpression were hindered by the co-overexpression of KCNQ1OT1. Furthermore, we found a direct interaction between miR-140-3p and the hypoxia-inducible factor-1α (HIF-1α), which was suppressed by the upregulation of KCNQ1OT1 in OGD/R. Our results indicate that KCNQ1OT1 exacerbates cerebral ischemia-reperfusion injury by targeted binding to miR-140-3p, thus interfering its direct interaction with HIF-1α. These data provide novel therapeutic targets in the cerebral ischemic stroke.

Cumulative procedural pain and brain development in very preterm infants: A systematic review of clinical and preclinical studies

Very preterm infants may manifest neurodevelopmental impairments, even in the absence of brain lesions. Pathogenesis is complex and multifactorial. Evidence suggests a role of early adversities on neurodevelopmental outcomes, via epigenetic regulation and changes in brain architecture. In this context, we focused on cumulative pain exposure which preterm neonates experience in neonatal intensive care unit (NICU). We systematically searched for: i) evidence linking pain with brain development and exploring the potential pathogenetic role of epigenetics; ii) preclinical research supporting clinical observational studies. Nine clinical neuroimaging studies, during neonatal or school age, mostly from the same research group, revealed volume reduction of white and gray matter structures in association with postnatal pain exposure. Three controlled animal studies mimicking NICU settings found increased cell death or apoptosis; nevertheless, eligible groups were limited in size. Epigenetic modulation (SLC6A4 promoter methylation) was identified in only two clinical trials. We call for additional research and, although knowledge gaps, we also point out the urgent need of minimizing painful procedures in NICUs.

Long non-coding RNA MIAT regulates blood tumor barrier permeability by functioning as a competing endogenous RNA

Blood-tumor barrier (BTB) presents a major obstacle to brain drug delivery. Therefore, it is urgent to enhance BTB permeability for the treatment of glioma. In this study, we demonstrated that MIAT, ZAK, and phosphorylated NFκB-p65 (p-NFκB-p65) were upregulated, while miR-140-3p was downregulated in glioma-exposed endothelial cells (GECs) of BTB compared with those in endothelial cells cocultured with astrocytes (ECs) of blood-brain barrier (BBB). MIAT inhibited miR-140-3p expression, increased the expression of ZAK, enhanced the ratio of p-NFκB-p65:NFκB-p65, and promoted the endothelial leakage of BTB. Our current study revealed that miR-140-3p was complementary to the ZAK 3'untranslated regions (3'-UTR), and luciferase activity of ZAK was inhibited by miR-140-3p in 293T cells. MiR-140-3p silencing resulted in an increase in BTB permeability by targeting ZAK, while overexpression of miR-140-3p had the opposite results in GECs of BTB. Overexpression of ZAK induced an increase in BTB permeability, and this effect was related to ZAK's ability to mediate phosphorylation of NFκB-p65. Conversely, ZAK silencing get opposite results in GECs of BTB. As a molecular sponge of miR-140-3p, MIAT attenuated its negative regulation of the target gene ZAK by adsorbing miR-140-3p. P-NFκB-p65 as a transcription factor negatively regulated the expression of TJ-associated proteins by means of chip assay and luciferase assay. Single or combined application of MIAT and miR-140-3p effectively promoted antitumor drug doxorubicin (Dox) across BTB to induce apoptosis of glioma cells. In summary, MIAT functioned as a miR-140-3p sponge to regulate the expression of its target gene ZAK, which contribution to phosphorylation of NFκB-p65 was associated with an increase in BTB permeability by down-regulating the expression of TJ associated proteins, thereby promoting Dox delivery across BTB. These results might provide a novel strategy and target for chemotherapy of glioma.