Xue Yang

Circular RNAs (circRNAs) are connected at the 3' and 5' ends by exon or intron cyclization, forming a complete ring structure. circRNA is more stable and conservative than linear RNA and abounds in various organisms. In recent years, increasing numbers of reports have found that circRNA plays a major role in the biological functions of a network of competing endogenous RNA (ceRNA). circRNAs can compete together with microRNAs (miRNAs) to influence the stability of target RNAs or their translation, thus, regulating gene expression at the transcriptional level. circRNAs are involved in biological processes such as tumor cell proliferation, apoptosis, invasion, and migration as ceRNAs. circRNAs, therefore, represent promising candidates for clinical diagnosis and treatment. Here, we review the progress in studying the role of circRNAs as ceRNAs in tumors and highlight the participation of circRNAs in signal transduction pathways to regulate cellular functions.

BACKGROUND: Subarachnoid hemorrhage (SAH) results in many brain dysfunctions and the neuroprotective function of puerarin after brain damage has been demonstrated in several studies. But whether puerarin can reduce brain nerve damage after SAH is not clear.In this study, we hypothesized that puerarin had the neuroprotective effect after SAH, and this protection could be mediated by bothBcl-2/Bax/Cleaved caspase-3 and SIRT3/SOD2 apoptotic signaling pathways. METHODS: First, we used neurological score, brain water content and so on to detect the neurological deficits after SAH. Then apoptosis neuron rate was detected by TUNEL staining. Western blot was carried out to explore the alteration of Blc-2, Bax, cleaved caspase-3 and Sirt3.Also, ROS acitivity and As-lysine level of SOD2 should be detected with assays. RESULTS: We demonstrate that puerarin attenuated the neurological deficits, effectively relieves cerebral edema, and reduce BBB disruption in SAH mice.And we revealed that a reduced rate of apoptosis neuron has been found out in puerarin treatment after SAH. In addition, obviously higher ratio of Blc-2/Bax and decreased expression of cleaved caspase-3 in puerarin-treated SAH micecomparing with vehicle-treated SAH animals had been found. Furthermore, puerarin effectively reversed these alterations in expression and inhibits ROSproduction induced by SAH. Also, puerarin can increase SOD activation after SAH and protect the expression of Sirt3 after SAH. CONCLUSIONS: In coclusion, puerarin can provide potential neuroprotection from the SAH damages, and can be act as a novel therapy for SAH.

Methamphetamine (METH) is a popular new-type psychostimulant drug with complicated neurotoxicity. In spite of mounting evidence on METH-induced damage of neural cell, the accurate mechanism of toxic effect of the drug on central nervous system (CNS) has not yet been completely deciphered. Besides, effective treatment strategies toward METH neurotoxicity remain scarce and more efficacious drugs are to be developed. In this review, we summarize cellular and molecular bases that might contribute to METH-elicited neurotoxicity, which mainly include oxidative stress, excitotoxicity, and neuroinflammation. We also discuss some drugs that protect neural cells suffering from METH-induced neurotoxic consequences. We hope more in-depth investigations of exact details that how METH produces toxicity in CNS could be carried out in future and the development of new drugs as natural compounds and immunotherapies, including clinic trials, are expected.

MicroRNAs involved in keratinocyte migration and wound healing are largely unknown. Here, we revealed the indispensable role of miR-21 in keratinocyte migration and in re-epithelialization during wound healing in mice. In HaCaT cell, miR-21 could be upregulated by TGF-β1. Similar to the effect of TGF-β1, miR-21 overexpression promoted keratinocyte migration. Conversely, miR-21 knockdown attenuated TGF-β1-induced keratinocyte migration, suggesting that miR-21 was essential for TGF-β-driven keratinocyte migration. Furthermore, we found that miR-21 was upregulated during wound healing, coincident with the temporal expression pattern of TGF-β1. Consistently, knockdown of endogenous miR-21 using a specific antagomir dramatically delayed re-epithelialization possibly due to the reduced keratinocyte migration. TIMP3 and TIAM1, direct targets of miR-21, were verified to be regulated by miR-21 in vitro and in vivo, indicating that these two molecules might contribute to miR-21-induced keratinocyte migration. Taken together, our results demonstrate that miR-21 promotes keratinocyte migration and boosts re-epithelialization during skin wound healing.