Phosphorylation of NMDA receptors by cyclin B/CDK1 modulates calcium dynamics and mitosis

NMDA receptor-mediated Ca2+ signaling: Impact on cell cycle regulation and the development of neurodegenerative diseases and cancer

NMDA receptors are Ca2+-permeable ligand-gated ion channels that mediate fast excitatory transmission in the central nervous system. NMDA receptors regulate the proliferation and differentiation of neural progenitor cells and also play critical roles in neural plasticity, memory, and learning. In addition to their physiological role, NMDA receptors are also involved in glutamate-mediated excitotoxicity, which results from excessive glutamate stimulation, leading to Ca2+ overload, and ultimately to neuronal death. Thus, NMDA receptor-mediated excitotoxicity has been linked to several neurodegenerative diseases such as Alzheimer's, Parkinson's, Huntington's, dementia, and stroke. Interestingly, in addition to its effects on cell death, aberrant expression or activation of NMDA receptors is also involved in pathological cellular proliferation, and is implicated in the invasion and proliferation of various types of cancer. These disorders are thought to be related to the contribution of NMDA receptors to cell proliferation and cell death through cell cycle modulation. This review aims to discuss the evidence implicating NMDA receptor activity in cell cycle regulation and the link between aberrant NMDA receptor activity and the development of neurodegenerative diseases and cancer due to cell cycle dysregulation. The information presented here will provide insights into the signaling pathways and the contribution of NMDA receptors to these diseases, and suggests that NMDA receptors are promising targets for the prevention and treatment of these diseases, which are leading causes of death and disability worldwide.

Long Non-Coding RNA-Cardiac-Inducing RNA 6 Mediates Repair of Infarcted Hearts by Inducing Mesenchymal Stem Cell Differentiation into Cardiogenic Cells through Cyclin-Dependent Kinase 1

This study aims to investigate the induction effect of LncRNA-CIR6 on MSC differentiation into cardiogenic cells in vitro and in vivo. In addition to pretreatment with Ro-3306 (a CDK1 inhibitor), LncRNA-CIR6 was transfected into BMSCs and hUCMSCs using jetPRIME. LncRNA-CIR6 was further transfected into the hearts of C57BL/6 mice via 100 μL of AAV9-cTnT-LncRNA-CIR6-ZsGreen intravenous injection. After three weeks of transfection followed by AMI surgery, hUCMSCs (5 × 105/100 μL) were injected intravenously one week later. Cardiac function was evaluated using VEVO 2100 and electric mapping nine days after cell injection. Immunofluorescence, Evans blue-TTC, Masson staining, FACS, and Western blotting were employed to determine relevant indicators. LncRNA-CIR6 induced a significant percentage of differentiation in BMSCs (83.00 ± 0.58)% and hUCMSCs (95.43 ± 2.13)% into cardiogenic cells, as determined by the expression of cTnT using immunofluorescence and FACS. High cTNT expression was observed in MSCs after transfection with LncRNA-CIR6 by Western blotting. Compared with the MI group, cardiac contraction and conduction function in MI hearts treated with LncRNA-CIR6 or combined with MSCs injection groups were significantly increased, and the areas of MI and fibrosis were significantly lower. The transcriptional expression region of LncRNA-CIR6 was on Chr17 from 80209290 to 80209536. The functional region of LncRNA-CIR6 was located at nucleotides 0-50/190-255 in the sequence. CDK1, a protein found to be related to the proliferation and differentiation of cardiomyocytes, was located in the functional region of the LncRNA-CIR6 secondary structure (from 0 to 17). Ro-3306 impeded the differentiation of MSCs into cardiogenic cells, while MSCs transfected with LncRNA-CIR6 showed a high expression of CDK1. LncRNA-CIR6 mediates the repair of infarcted hearts by inducing MSC differentiation into cardiogenic cells through CDK1.

Hepatoprotective effect of syringin combined with costunolide against LPS-induced acute liver injury in L-02 cells via Rac1/AKT/NF-κB signaling pathway

Acute liver injury (ALI) leads to abnormal liver function and damage to liver cells. Syringin (syr) and costunolide (cos) are the major extracts from Dolomiaea souliei (Franch.) C.Shih (D. souliei), showing diverse biological functions in various biological processes. We explored the underlying hepatoprotective effects of syr+cos against LPS-induced ALI. Cell viability and proliferation were assessed using an MTT assay and immunofluorescence staining. Flow cytometry analysis was used to detect cell cycle distribution and apoptosis. ELISA was utilized to measure liver function and antioxidant stress indexes. qRT-PCR and western blotting was performed to determine mRNA and protein levels respectively. Using shRNA approach to Rac1 analyzed transcriptional targets. The results showed that syr+cos promoted L-02 cell proliferation, inhibiting the cell apoptosis and blocking cell cycle in G1 and G2/M phase. Syr+cos decreased the production of ALT, AST, LDH, MDA and ROS while increased SOD and CAT activities. Pretreated with syr+cos may decrease expressions of caspase-3,7,9, NF-κB, TNF-α proteins, Cyclin B, CDK1 and p-IκB proteins while p-IκB increased. Silencing of Rac-1 may protect the liver by increasing AKT, S473, T308 and reducing p-AKT proteins. Syr+cos exhibits anti-ALI activity via Rac1/AKT/NF-κB signaling pathway which might act as an effective candidate drug for the treatment of ALI.

Design, synthesis and anticancer evaluation of polymethoxy aurones as potential cell cycle inhibitors

Background

Cancer is the most fatal disease in humans and the aberrant activity of various cell cycle proteins results in uncontrolled tumor cell proliferation, thus, regulating the cell cycle is an attractive target in cancer therapy.

Objectives

Aurone is a naturally occurring active compound with a wide range of biological activities, of which 3, 4, 5-trimethoxyphenyl (TMP) is an important microtubule targeting pharmacophore. Based on the pharmacophore combination principle, we incorporate the TMP pharmacophore into the aurone structure and design a novel polymethoxy derivative that is expected to inhibit tumor cell proliferation through regulating the cell cycle.

Methods

By introducing different substituents on C-4' and C-3', a series of new 4, 5, 6-trimethoxy aurone derivatives have been designed and synthesized. DU145, MCF-7 and H1299 cell lines were selected to evaluate their anticancer activity. The compound with the best cytotoxicity was then selected and the anticancer mechanisms were investigated by network pharmacology, flow cytometry, Western blot, and cell heat transfer assay. ADMET prediction evaluated the draggability of aurone derivatives.

Results

Aurones 1b and 1c have selective anti-proliferative activity against DU145 cells. Among them, the compound 1c have better cytotoxicity against DU145. Compound 1c could bind the active cavity of CyclinB1/CDK1/CKS complex protein and induced G2/M phase arrest of DU145 cells by regulating the expression of CyclinB1 and p21. Compound 1c satisfies the Lipinski rule, is suitable for the absorption and metabolism index, and has a lower risk of cardiac toxicity.

Conclusions

Polymethoxy aurones 1c might function as a CyclinB1/CDK1 inhibitor that deserved to be further developed for the treatment of prostate cancer.

Roles of N-Methyl-D-Aspartate Receptors (NMDARs) in Epilepsy

Epilepsy is one of the most common neurological disorders characterized by recurrent seizures. The mechanism of epilepsy remains unclear and previous studies suggest that N-methyl-D-aspartate receptors (NMDARs) play an important role in abnormal discharges, nerve conduction, neuron injury and inflammation, thereby they may participate in epileptogenesis. NMDARs belong to a family of ionotropic glutamate receptors that play essential roles in excitatory neurotransmission and synaptic plasticity in the mammalian CNS. Despite numerous studies focusing on the role of NMDAR in epilepsy, the relationship appeared to be elusive. In this article, we reviewed the regulation of NMDAR and possible mechanisms of NMDAR in epilepsy and in respect of onset, development, and treatment, trying to provide more evidence for future studies.

CDK1 promotes the stemness of lung cancer cells through interacting with Sox2

OBJECTIVES

The promoting roles of cyclin dependent kinase 1 (CDK1) have been revealed in various tumors, however, its effects in the progression of cancer stem cells are still confusing. This work aims to explore the roles of CDK1 in regulating the stemness of lung cancer cells.

METHODS

Online dataset analysis was performed to evaluate the correlation between CDK1 exression and the survival of lung cancer patients. RT-qPCR, western blot, cell viability, sphere-formation analysis and ALDH activity detection were used to investigate the roles of CDK1 on lung cancer cell stemness, viability and chemotherapeutic sensitivity. Immunocoprecipitation (Co-IP) analysis and rescuing experiments were performed to reveal the underlying mechanisms contributing to CDK1-mediated effects on lung cancer cell stemness.

RESULTS

CDK1 mRNA expression was negatively correlated with the overall survival of lung cancer patients and remarkably increased in tumor spheres formed by lung cancer cells compared to the parental cells. Additionally, CDK1 positively regulated the stemness of lung cancer cells. Mechanistically, CDK1 could interact with Sox2 protein, but not other stemness markers (Oct4, Nanog and CD133). Furthermore, CDK1 increased the phosphorylation, cytoplasm-nuclear translocation and transcriptional activity of Sox2 protein in lung cancer cells. Moreover, CDK1 positively regulated the stemness of lung cancer cells in a Sox2-dependent manner. Finally, we revealed that inhibition of CDK1 enhanced the chemotherapeutic sensitivity, which was also rescued by Sox2 overexpression.

CONCLUSIONS

This work reveals a novel CDK1/Sox2 axis responsible for maintaining the stemness of lung cancer cells.