Celastrol inhibits angiogenesis and the biological processes of MDA-MB-231 cells via the DEGS1/S1P signaling pathway.

Celastrol (Cel) shows potent antitumor activity in various experimental models. This study examined the relationship between Cel's antivascular and antitumor effects and sphingolipids. CCK-8 assay, transwell assay, Matrigel, PCR-array/RT-PCR/western blotting/immunohistochemistry assay, ELISA and HE staining were used to detect cell proliferation, migration and invasion, adhesion and angiogenesis, mRNA and protein expression, S1P production and tumor morphology. The results showed that Cel could inhibit proliferation, migration or invasion, adhesion and angiogenesis of human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 cells by downregulating the expression of degenerative spermatocyte homolog 1 (DEGS1). Transfection experiments showed that downregulation of DEGS1 inhibited the above processes and sphingosine-1-phosphate (S1P) production of HUVECs and MDA-MB-231 cells, while upregulation of DEGS1 had the opposite effects. Coculture experiments showed that HUVECs could promote proliferation, migration and invasion of MDA-MB-231 cells through S1P/sphingosine-1-phosphate receptor (S1PR) signaling pathway, while Cel inhibited these processes in MDA-MB-231 cells induced by HUVECs. Animal experiments showed that Cel could inhibit tumor growth in nude mice. Western blotting, immunohistochemistry and ELISA assay showed that Cel downregulated the expression of DEGS1, CD146, S1PR1-3 and S1P production. These data confirm that DEGS1/S1P signaling pathway may be related to the antivascular and antitumor effects of cel.

Triptolide Inhibits the Biological Processes of HUVECs and HepG2 Cells via the Serine Palmitoyltransferase Long Chain Base Subunit 2/Sphingosine-1-Phosphate Signaling Pathway.

Triptolide (TP) has demonstrated innumerous biological effects and pharmacological potential against different cancer types. Hepatocellular carcinoma has a high incidence in men, and its incidence is increasing year by year. Studies have shown that angiogenesis plays an important role in the formation of tumors and that angiogenesis is closely related to tumor growth and metastasis. Deregulation of sphingolipids signaling has been associated with several pathological conditions, including cancer. In the present study, we aimed at exploring the potential molecular mechanism of TP's antivascular and antitumor effects in vitro from the perspective of sphinolipids. Human umbilical vein endothelial cells (HUVECs) and HepG2 cells were, respectively, treated with different concentrations of TP and transfected. Then, the effect of HUVECs on HepG2 cells was investigated using a three-dimensional coculture model system. CCK-8 assay was performed for cell proliferation. Cell migration and invasion abilities were assessed using the transwell assay. Cell adhesion and tube formation were detected by Matrigel. RT-PCR and western blotting were used to detect the mRNA and protein expression. The S1P production was measured via ELISA assay. Our results showed that TP inhibited HUVECs and HepG2 cells proliferation, migration, invasion, adhesion, angiogenesis, and serine palmitoyltransferase long chain base subunit 2 (SPTLC2) expression; upregulating SPTLC2 facilitated the proliferation, migration, invasion, adhesion, angiogenesis, and sphingosine-1-phosphate (S1P) production of HUVECs and HepG2 cells, while interfering with SPTLC2 expression inhibited them; HUVECs facilitated the proliferation, migration, invasion, S1P production, S1PR1, and S1PR2 expression of HepG2 cells, while S1PR3 expression was decreased. In conclusion, SPTLC2 may be associated with the antivascular and antitumor effects of TP, and SPTLC2 is expected to become a new marker for tumor therapy. HUVECs can promote the proliferation, migration, and invasion of HepG2 cells, which may be related to the S1P/sphingosine-1-phosphate receptor (S1PR) signaling pathway.

Symptomatic Infection is Associated with Prolonged Duration of Viral Shedding in Mild Coronavirus Disease 2019: A Retrospective Study of 110 Children in Wuhan.

BACKGROUND: Information regarding viral shedding in children with coronavirus disease 2019 (COVID-19) was limited. This study aims to investigate the clinical and laboratory characteristics associated with viral shedding in children with mild COVID-19. METHODS: The clinical and laboratory information of 110 children with COVID-19 at Wuhan Children's Hospital, Wuhan, China, from January 30 to March 10, 2020, were analyzed retrospectively. RESULTS: The median age was 6 years old. The median period of viral shedding of COVID-19 was 15 days (interquartile range [IQR], 11-20 days) as measured from illness onset to discharge. This period was shorter in asymptomatic patients (26.4%) compared with symptomatic patients (73.6%) (11 days vs. 17 days). Multivariable regression analysis showed increased odds of symptomatic infection was associated with age <6 years (odds ratio [OR] 8.94, 95% confidence interval [CI]: 2.55-31.35; P = 0.001), hypersensitive C-reactive protein >3.0 mg/L (OR 4.89; 95% CI: 1.10-21.75; P = 0.037) and presenting pneumonia in chest radiologic findings (OR 8.45; 95% CI: 2.69-26.61; P < 0.001). Kaplan-Meier analysis displayed symptomatic infection (P < 0.001), fever (P = 0.006), pneumonia (P = 0.003) and lymphocyte counts <2.0 × 10/L (P = 0.008) in children with COVID-19 were associated with prolonged duration of viral shedding in children with COVID-19. CONCLUSION: Prolonged duration of viral shedding in children with COVID-19 was associated with symptomatic infection, fever, pneumonia and lymphocyte count less than 2.0 × 10/L. Monitoring of symptoms could help to know the viral shedding in children with COVID-19.

Comparison of tonal response properties of primary auditory cortex neurons of adult rats under urethane and ketamine anesthesia.

OBJECTIVE: To compare tonal response properties of neurons in the primary auditory cortex of Sprague-Dawley rats anesthetized with urethane and ketamine-xylazine. METHODS: Forty-five female Sprague-Dawley rats (200-250 g) were randomized into two groups and anesthetized with urethane or ketamine-xylazine. Tone pips were chosen as the stimuli to obtain the action potentials of the single neurons by in vivo cell-attached recording. The features of the action potentials were extracted with Matlab software to comparatively analyze the acoustic response properties of the neurons between the two anesthetic groups. RESULTS: The Q values and the characteristic frequencies were independent of the types of anesthetic agents, but with urethane anesthesia, the neurons tended to have higher minimum thresholds, lower spontaneous firing rates, longer response latencies, and more frequent occurrence of tuning with stronger inhibition compared to those in ketamine-xylazine group. CONCLUSION: Urethane and ketamine might have no obvious impact on the transmission pathway of frequency tuning from the periphery to the auditory cortex, but neurons from rats with urethane anesthesia receive enhanced inhibition mediated by the interneurons or have a lower intrinsic excitability.