NLRP3 inflammasome plays an essential role in innate immunity, yet the activation mechanism of NLRP3 inflammasome is not clear. In human or animal models, inappropriate NLRP3 inflammasome activation is implicated in many NLRP3-related diseases, such as tumors, inflammatory diseases and autoimmune diseases. Until now, a great number of inhibitors have been used to disturb the related signaling pathways, such as IL-1β blockade, IL-18 blockade and caspase-1 inhibitors. Unfortunately, most of these inhibitors just disturb the signaling pathways after the activation of NLRP3 inflammasome. Inhibitors that directly regulate NLRP3 to abolish the inflammation response may be more effective. NEK7 is a multifunctional kinase affecting centrosome duplication, mitochondrial regulation, intracellular protein transport, DNA repair and mitotic spindle assembly. Researchers have made significant observations on the regulation of gene transcription or protein expression of the NLRP3 inflammasome signaling pathway by NEK7. Those signaling pathways include ROS signaling, potassium efflux, lysosomal destabilization, and NF-κB signaling. Furthermore, NEK7 has been proved to be involved in many NLRP3-related diseases in humans or in animal models. Inhibitors focused on NEK7 may regulate NLRP3 to abolish the inflammation response and NEK7 may be a potential therapeutic target for NLRP3-related diseases.
Emerging evidence indicates that DJ-1 is highly expressed in different cancers. It modulates cancer progression, including cell proliferation, cell apoptosis, invasion, and metastasis. However, its role in colorectal cancer (CRC) remains poorly defined. The current study noted increased DJ-1 expression in CRC tumor tissue and found that its expression was closely related to clinical-pathological features. Similarly, DJ-1 increased in CRC cells (SW480, HT-29, Caco-2, LoVo, HCT116, and SW620), and especially in SW480 and HCT116 cells. Functional analyses indicated that overexpression of DJ-1 promoted CRC cell invasion, migration, and proliferation in vitro and in vivo. Mechanistic studies indicated that DJ-1 increased in CRC cell lines, activated specific protein cyclin-D1, and modulated the MDM2/p53 signaling pathway by regulating the levels of the downstream factors Bax, Caspase-3, and Bcl-2, which are related to the cell cycle and apoptosis. Conversely, knockdown of DJ-1 upregulated p53 expression by disrupting the interaction between p53 and MDM2 and inhibiting CRC cell proliferation, revealing the pro-oncogenic mechanism of DJ-1 in CRC. In conclusion, the current findings provide compelling evidence that DJ-1 might be a promoter of CRC cell invasion, proliferation, and migration via the cyclin-D1/MDM2-p53 signaling pathway. Findings also suggest its potential role as a postoperative adjuvant therapy for patients with CRC.
4-anilinoquinazoline-containing inhibitors of the epidermal growth factor receptor (EGFR) are widely used in non-small cell lung cancer patients with mutated EGFR, but they are less effective in multiple myeloma (MM), a fatal malignancy derived from plasma cells. The present study designed a series of novel compounds by conjugating a peroxide bridge to the 4-anilinoquinazoline pharmacophore. Further studies showed that these agents such as 4061 and 4065B displayed potent activity to induce MM cell apoptosis by upregulating pro-apoptotic p53 and Bax while downregulating pro-survival Bcl-2. The mechanistic analysis revealed that both 4061 and 4065B inhibited IGF1-R, AKT and mTOR activation in a concentration dependent manner but had no effects on the expression of their total proteins, suggesting the conjugates of endoperoxide and 4-anilinoquinazoline may exert its anti-myeloma activity by targeting the IGF1-R/AKT/mTOR pathway.
Transcultured human skin derived precursors (tSKPs) from adherent monolayer culture system have similar characteristics as traditional skin derived precursors (SKPs), making tSKPs a suitable candidate for regenerative medicine. tSKPs can differentiate into fibroblasts. However, little is known about the molecular mechanism of the transition from tSKPs to fibroblasts. Here, we compared the transcriptional profiles of human tSKPs and tSKPs-derived fibroblasts (tFBs) by RNA-Sequence aiming to determine the candidate genes and pathways involving in the differentiation process. A total of 1042 differentially expressed genes (DEGs) were identified between tSKPs and tFBs, with 490 genes up-regulated and 552 genes down-regulated. Our study showed that these DEGs were significantly enriched in tumor necrosis factor signaling pathway, focal adhesion, extracellular matrix-receptor interaction and phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) signaling pathway. A further transcription factors (TFs) analysis of DEGs revealed the significantly down-expressed TFs (p21, Foxo1and Foxc1) in tFBs were mostly the downstream nodes of PI3K-Akt signaling pathway, which suggested PI3K-Akt signaling pathway might play an important role in tSKPs differentiation. The results of our study are useful for investigating the molecular mechanisms in tSKPs differentiation into tFBs, making it possible to take advantage of their potential application in regenerative medicine.
Dimethylarginine dimethylaminohydrolase-1 (DDAH1) maintains nitric oxide (NO) bioavailability by degrading asymmetric dimethylarginine (ADMA), which is an endogenous inhibitor of nitric oxide synthase (NOS). It has been well established that DDAH1 and exercise play crucial roles in promoting cardiac angiogenesis under pathological conditions. However, the role of DDAH1 in exercise-induced cardiac angiogenesis remains unclear. In this study, we focused on the change in DDAH1 in response to moderate exercise and the underlying mechanism of exercise-induced cardiac angiogenesis. Eight-week-old male DDAH1 global knockout (KO) mice and DDAH1flox/flox mice (wild-type) were randomly divided into sedentary groups (control) and swimming groups (exercise). After eight weeks of swimming at five days per week, all the mice were anesthetized and sacrificed. Histological examination and Western blot analysis were performed. There were low levels of myocardial capillaries in DDAH1 KO mice under control and exercise conditions. Notably, exercise elevated DDAH1 protein expression, as observed by Western blot analysis. The common cardiac angiogenesis biomarkers vascular endothelial growth factor (VEGF) and Caveolin-1 were increased during exercise. A significant difference in VEGF was observed between the DDAH1 KO and wild-type groups. Similarly, increased Caveolin-1 expression was abrogated in DDAH1 KO mice. Furthermore, we tested the R-Ras/AKT/GSK3β signaling pathway to study the underlying molecular mechanism. DDAH1 may regulate the R-Ras/AKT/GSK3β pathway due to distinct protein changes in this pathway in the DDAH1 KO and wild-type groups. Our findings suggest that DDAH1 plays an important role in exercise-induced cardiac angiogenesis by regulating the R-Ras/AKT/GSK3βsignaling pathway.
Glioblastoma is one of the most difficult cancers to treat with a 5-year overall survival rate less than 5%. Temozolomide (TMZ) is an effective drug for prolonging the overall survival time of patients, while drug-resistance is an important clinical problem at present. Pennogenin-3-α-L-rhamnopyranosyl-(1→4)-[α-Lrhamno-pyranosyl-(1→2)]- β-D-glucopyranoside (N45), a steroidal saponin, was isolated from the rhizomes of Paris vietnamensis (Takht.), which is used as a Traditional Chinese Medicine and has been reported to possess preclinical anticancer efficacy in various cancer types. However, the mechanism of the inhibition of N45 on glioblastoma cells and its possible application in the treatment of chemotherapy-resistant glioblastoma cells are still unknown. In this study, we use cellular methodological experiments including cell counting kit-8 (CCK-8) assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining assay, flow cytometry assay, transmission electron microscopy (TEM) and Western blot. The results show that N45 significantly suppresses the proliferation of glioblastoma cells and TMZ-resistant glioblastoma cells (U87R) by inducing mitochondrial apoptosis through reactive oxygen species (ROS)/phosphoinositide 3-kinase (PI3K)/Akt signal pathway, and the N-acetyl-L-cysteine (NAC) combined with N45 effectively reduced N45-mediated apoptosis and reversed the inhibition of PI3K/Akt signal pathway. In addition, N45 decreased the drug-resistance by down-regulation of nuclear factor kappa-B p65 (NF-κB p65) to attenuate O6-methylguanine-DNA methyltransferase (MGMT) in TMZ-resistant glioblastoma cells (U87R). Our findings proved that N45 might be a potential therapeutic agent against glioblastoma and TMZ-resistant glioblastoma, promising to be a potential agent to reduce drug resistance.
To assess the effectiveness of response strategies of avoiding large gatherings or crowded areas and to predict the spread of COVID-19 infections in Japan, we developed a stochastic transmission model by extending the Susceptible-Infected-Removed (SIR) epidemiological model with an additional modeling of the individual action on whether to stay away from the crowded areas. The population were divided into three compartments: Susceptible, Infected, Removed. Susceptible transitions to Infected every hour with a probability determined by the ratio of Infected and the congestion of area. The total area consists of three zones crowded zone, mid zone and uncrowded zone, with different infection probabilities characterized by the number of people gathered there. The time for each people to spend in the crowded zone is curtailed by 0, 2, 4, 6, 7, and 8 hours, and the time spent in mid zone is extended accordingly. This simulation showed that the number of Infected and Removed will increase rapidly if there is no reduction of the time spent in crowded zone. On the other hand, the stagnant growth of Infected can be observed when the time spent in the crowded zone is reduced to 4 hours, and the growth number of Infected will decrease and the spread of the infection will subside gradually if the time spent in the crowded zone is further cut to 2 hours. In conclusions The infection spread in Japan will be gradually contained by reducing the time spent in the crowded zone to less than 4 hours.
In late March and early April 2020, the antimalarial drug, chloroquine, has been approved as an emergency treatment for the coronavirus disease 2019 (COVID-19) in the United States and in Europe. Although infrequent, neuropsychiatric symptoms have been reported in patients who received chloroquine for the treatment of malaria or autoimmune diseases. In this study, aiming to investigate these adverse events (AEs) using a large self-reporting database, we conducted a disproportionality analysis for the detection of neuropsychiatric AE signals associated with the use of chloroquine (or hydroxychloroquine), reported to FDA Adverse Event Reporting System (FAERS) database between the fourth quarter of 2012 and the fourth quarter of 2019. We included 2,389,474 AE cases, among which 520 cases developed neuropsychiatric AE following the use of chloroquine. Adjusted reporting odds ratio (ROR) for the development of each of the neuropsychiatric AEs following the use of chloroquine was calculated using a multilevel model: exposure to chloroquine was associated with a statistically significant high reporting of amnesia, delirium, hallucinations, depression, and loss of consciousness, (lower 95% confidence interval of the adjusted ROR > 1), although the degree of increase in their ROR was limited. There was no statistically significant high reporting of any other neuropsychiatric AE, including suicide, psychosis, confusion, and agitation. Current pharmacovigilance study results did not suggest any potential link between the use of chloroquine and an increased risk of suicide, psychosis, confusion, and agitation, which would be informative during the emergency use of chloroquine for the treatment of COVID-19.
The ST3GAL4 gene encodes the enzyme Galβ1-4GlcNAc α2,3 sialyltransferase (ST3Gal IV). This enzyme participates in the synthesis of the sialyl Lewis x antigen. In different cancer types altered expression of this antigen has been reported. The transcriptional regulation of this gene is very complex, different mRNA variants (V1-V10) have been reported and are originated by the activity of different promoters and alternative splicing. Only the promoter that gives rise to the V3 variant has not been previously reported. The objective of this work was to identify and characterize the V3 promoter of the ST3GAL4 gene. For this, the putative V3 promoter of the ST3GAL4 gene was delimited by in silico analysis. The complete promoter and smaller versions were cloned in a reporter plasmid. The constructs were transfected in the HaCaT cells and the promoter activity was evaluated by luciferase reporter assays. The cloned region showed promoter activity, and the basal activity was not dependent on TATA boxes. However, the GC boxes, an initiator element (Inr) and downstream promoter element (DPE) could contribute to basal activity. The promoter contains several binding sites for the nuclear factor of activated T-cells (NFAT) that could participate in inducible activity during the immune response. The minimal promoter corresponds to a fragment of approximately 300 bp, located in the position -347 b to -40 b. The characterization of the V3 promoter of the ST3GAL4 gene completes the study of the four promoters of this gene, this contributes to the understanding of its complex transcription regulation.
Health care reform is a worldwide problem. To address the problems of costs, access, quality, efficiency, and equity, China initiated healthcare reform in 2009. The progress of China's healthcare reform has been internationally recognized as the reform has expanded insurance coverage and improved access to and reduced the costs of care over the ten-year period from 2008 to 2018. To achieve sustainable goals, attention must be focused on whether and how the reform encourages physicians. This paper highlights the role of physicians, the challenges that need to be addressed, and the direction in which to advance health reform in China from the perspective of physicians. The slow-growing and aging physician population cannot meet the ever-increasing medical demand. Physicians have a heavy workload, work long hours, have unsatisfactory income, and have a fraught relationship with patients. The situation calls for rethinking the value of physicians and rebuilding trust between physicians and patients. Further healthcare reform is needed to equitably allocate physicians with adequate training, time, and resources to deliver evidence-based practices and patient-centered care.
Drugs that are specifically efficacious against SARS-CoV-2 have yet to be established. Chloroquine and hydroxychloroquine have garnered considerable attention for their potential to treat coronavirus disease 2019 (COVID-19). Increasing evidence obtained from completed clinical studies indicates the prospects for chloroquine/hydroxychloroquine to treat COVID-19. More randomized control clinical studies are warranted to determine the feasibility of these two drugs in treating COVID-19.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that has developed in late 2019 and 2020 is a serious threat to human health. With no vaccines or drugs approved for prevention and treatment until now, all efforts at drug design and/or clinical trials of already approved drugs are worthy and creditable. Using structure-based drug selection for identification of SARS-CoV-2 protease inhibitors, old drugs such as macrolides (MAC) were predicted to be effective for COVID-19. Lately, the anti-viral effects of macrolides have attracted considerable attention. Very recently, hydroxychloroquine in combination with azithromycin treatment was reported to be effective for COVID-19. We believe that treatments with macrolides alone or in combination with other drugs are promising and open the possibility of an international strategy to fight this emerging viral infection.