Andrographolide inhibits hypoxia-induced hypoxia-inducible factor 1α and endothelin 1 expression through the heme oxygenase 1/CO/cGMP/MKP-5 pathways in EA.hy926 cells

Effect of RNA interference with HIF-1α on the growth of pulmonary artery endothelial cells in broiler chickens

Pulmonary artery remodeling is a characteristic feature of broiler ascites syndrome (BAS). Pulmonary artery endothelial cells (PAECs) regulated by HIF-1α play a critical role in pulmonary artery remodeling, but the underlying mechanisms of HIF-1α in BAS remain unclear. In this experiment, primary PAECs were cultured in vitro and were identified by coagulation factor VIII. After hypoxia and RNA interference, the mRNA and protein expression levels of HIF-1α and VEGF were determined by qPCR and Western blotting. The transcriptome profiles of PAECs were obtained by RNA sequencing. Our results showed that the positive rate of PAECs was more than 90%, hypoxia-induced promoted the proliferation and apoptosis of PAECs, and RNA interference significantly downregulated the expression of HIF-1α, inhibited the proliferation of PAECs, and promoted the apoptosis of PAECs. In addition, transcriptome sequencing analysis indicated that HIF-1α may regulate broiler ascites syndrome by mediating COL4A, vitronectin, vWF, ITGα8, and MKP-5 in the ECM, CAMs and MAPK pathways in PAECs. These studies lay the foundation for further exploration of the mechanisms of pulmonary artery remodeling, and HIF-1α may be a potentially effective gene for the prevention and treatment of BAS.

Novel wine in an old bottle: Preventive and therapeutic potentials of andrographolide in atherosclerotic cardiovascular diseases

Atherosclerotic cardiovascular disease (ASCVD) frequently results in sudden death and poses a serious threat to public health worldwide. The drugs approved for the prevention and treatment of ASCVD are usually used in combination but are inefficient owing to their side effects and single therapeutic targets. Therefore, the use of natural products in developing drugs for the prevention and treatment of ASCVD has received great scholarly attention. Andrographolide (AG) is a diterpenoid lactone compound extracted from Andrographis paniculata. In addition to its use in conditions such as sore throat, AG can be used to prevent and treat ASCVD. It is different from drugs that are commonly used in the prevention and treatment of ASCVD and can not only treat obesity, diabetes, hyperlipidaemia and ASCVD but also inhibit the pathological process of atherosclerosis (AS) including lipid accumulation, inflammation, oxidative stress and cellular abnormalities by regulating various targets and pathways. However, the pharmacological mechanisms of AG underlying the prevention and treatment of ASCVD have not been corroborated, which may hinder its clinical development and application. Therefore, this review summarizes the physiological and pathological mechanisms underlying the development of ASCVD and the in vivo and in vitro pharmacological effects of AG on the relative risk factors of AS and ASCVD. The findings support the use of the old pharmacological compound ('old bottle') as a novel drug ('novel wine') for the prevention and treatment of ASCVD. Additionally, this review summarizes studies on the availability as well as pharmaceutical and pharmacokinetic properties of AG, aiming to provide more information regarding the clinical application and further research and development of AG.

DUSP10 upregulation is a poor prognosticator and promotes cell proliferation and migration in glioma

Dual-specificity phosphatase 10 (DUSP10) correlates with inflammation, cytokine secretion, cell proliferation, survival, and apoptosis. However, its role in glioma is unclear. Herein, we sought to examine the expression and the underlying carcinogenic mechanisms of DUSP10 action in glioma. DUSP10 expression in glioma was significantly higher than that in normal brain tissues. High DUSP10 expression indicated adverse clinical outcomes in glioma patients. Increased DUSP10 expression correlated significantly with clinical features in glioma. Univariate Cox analysis showed that high DUSP10 expression was a potential independent marker of poor prognosis in glioma. Furthermore, DUSP10 expression in glioma correlated negatively with its DNA methylation levels. DNA methylation level of DUSP10 also correlated negatively with poor prognosis in glioma. More importantly, DUSP10 expression correlated positively with the infiltration of B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells in glioma. Gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis confirmed that DUSP10 participated in signaling pathways involved in focal adhesion, TNF cascade, Th17 cell differentiation, and NF-kappa B cascade. Finally, we uncovered that DUSP10 was dramatically upregulated in glioblastoma (GBM) cells and that the knockdown of DUSP10 inhibited glioma cell proliferation and migration. Our findings suggested that DUSP10 may serve as a potential prognostic biomarker in glioma.

Latent Variables Capture Pathway-Level Points of Departure in High-Throughput Toxicogenomic Data

Estimation of points of departure (PoDs) from high-throughput transcriptomic data (HTTr) represents a key step in the development of next-generation risk assessment (NGRA). Current approaches mainly rely on single key gene targets, which are constrained by the information currently available in the knowledge base and make interpretation challenging as scientists need to interpret PoDs for thousands of genes or hundreds of pathways. In this work, we aimed to address these issues by developing a computational workflow to investigate the pathway concentration-response relationships in a way that is not fully constrained by known biology and also facilitates interpretation. We employed the Pathway-Level Information ExtractoR (PLIER) to identify latent variables (LVs) describing biological activity and then investigated in vitro LVs' concentration-response relationships using the ToxCast pipeline. We applied this methodology to a published transcriptomic concentration-response data set for 44 chemicals in MCF-7 cells and showed that our workflow can capture known biological activity and discriminate between estrogenic and antiestrogenic compounds as well as activity not aligning with the existing knowledge base, which may be relevant in a risk assessment scenario. Moreover, we were able to identify the known estrogen activity in compounds that are not well-established ER agonists/antagonists supporting the use of the workflow in read-across. Next, we transferred its application to chemical compounds tested in HepG2, HepaRG, and MCF-7 cells and showed that PoD estimates are in strong agreement with those estimated using a recently developed Bayesian approach (cor = 0.89) and in weak agreement with those estimated using a well-established approach such as BMDExpress2 (cor = 0.57). These results demonstrate the effectiveness of using PLIER in a concentration-response scenario to investigate pathway activity in a way that is not fully constrained by the knowledge base and to ease the biological interpretation and support the development of an NGRA framework with the ability to improve current risk assessment strategies for chemicals using new approach methodologies.

Cadmium induces the expression of Interleukin-6 through Heme Oxygenase-1 in HK-2 cells and Sprague-Dawley rats

Cadmium is toxic to the kidney through mechanisms involving oxidative stress and inflammation. We studied reciprocal crosstalk among the oxidative stress, inflammation, and the nuclear Nrf2 pathway in cadmium-induced nephrotoxicity on HK-2 human renal proximal tubular epithelial cells. Cadmium chloride (CdCl₂) caused cell viability loss, Reactive Oxygen Species (ROS) generation, glutathione reduction, and Interleukin-6 (IL-6) expression, accompanied by Nrf2 activation and Heme Oxygenase-1 (HO-1) expression. Pharmacological treatments demonstrated cytotprotective and anti-inflammatory effects of Nrf2 activation. Intriguingly, inhibition of HO-1 activity mitigated cell viability loss and IL-6 expression in CdCl₂-treated cells. Parallel attenuation by HO-1 inhibitor was demonstrated in cadmium-induced ROS generation and glutathione reduction. CdCl₂-treated cells also increased levels of ferrous iron, cGMP, Mitogen-Activated Protein Kinases phosphorylation, as well as NF-κB DNA-binding activity. These increments were mitigated by antioxidant N-Acetyl Cysteine, HO-1 inhibitor SnPP, and PKG inhibitor KT5823, and were mimicked by the Carbon Monoxide-releasing compound. In the kidney cortex of CdCl₂-exposed Sprague-Dawley rats, we found similar renal injury, histological changes, ROS generation, IL-6 expression, and accompanied pro-oxidant and pro-inflammatory changes. These observations indicated that cadmium-induced nephrotoxicity was associated with oxidative stress and inflammation, and HO-1 likely acts as a linking molecule to induce nephrotoxicity-associated IL-6 expression upon cadmium exposure.

Role of Endothelin 1 on Proliferation and Migration of Human MCF-7 Cells

Objective

The aim of this study was to explore the role of endothelin 1 (ET-1) in human breast cancer proliferation and migration and antagonism of endothelin receptor A (ETAR) and endothelin receptor B (ETBR) by using the non-selective dual ETA/ETB receptor antagonist bosentan and determine its anti-proliferative, anti-metastatic, and apoptotic effects demonstrated by nuclear factor kappa B (NF-kB), vascular endothelial growth factor (VEGF), Caspase 3 and Caspase 9 expression on endothelin-induced proliferation of MCF-7 cell line in vitro.

Materials and Methods

A total of 8,000 cells were seeded into e-plates 24 hours after the cells were incubated with or without 10-4 M BOS (1 hour before ET-1 treatment); 10-7, 10-8, and 10-9 M ET-1 for 1-4 days.

Results

Whether ET-1 is present or not in the tumor area, bosentan exerts anti-proliferative effect on breast cancer. However, ET-1 and bosentan group showed important inhibitory effect on tumor migration compared to bosentan alone, which can be attributed to increased activity of ET-1 axis in the presence of ET-1. The imbalance among the NF-kB, caspases, and VEGF, which are predictive factors of carcinogenesis significantly improved after bosentan administration.

Conclusion

Our study definitely demonstrated ET-1 and its critical role in cancer progression with apoptotic and anti-apoptotic pathways (NF-κB) and VEGF expression, and migration analyses were also performed. The second major finding was that bosentan inhibited ET-1-mediated effects on tumor proliferation and migration.

MKP-5 Relieves Lipotoxicity-Induced Islet β-Cell Dysfunction and Apoptosis via Regulation of Autophagy

Mitogen-activated protein kinase phosphatase-5 (MKP-5) is a regulator of extracellular signaling that is known to regulate lipid metabolism. In this study, we found that obesity caused by a high-fat diet (HFD) decreased the expression of MKP-5 in the pancreas and primary islet cells derived from mice. Then, we further investigated the role of MKP-5 in the protection of islet cells from lipotoxicity by modulating MKP-5 expression. As a critical inducer of lipotoxicity, palmitic acid (PA) was used to treat islet β-cells. We found that MKP-5 overexpression restored PA-mediated autophagy inhibition in Rin-m5f cells and protected these cells from PA-induced apoptosis and dysfunction. Consistently, a lack of MKP-5 aggravated the adverse effects of lipotoxicity. Islet cells from HFD-fed mice were infected using recombinant adenovirus expressing MKP-5 (Ad-MKP-5), and we found that Ad-MKP-5 was able to alleviate HFD-induced apoptotic protein activation and relieve the HFD-mediated inhibition of functional proteins. Notably, HFD-mediated impairments in autophagic flux were restored by Ad-MKP-5 transduction. Furthermore, the autophagy inhibitor 3-methyladenine (3-MA) was used to treat Rin-m5f cells, confirming that the MKP-5 overexpression suppressed apoptosis, dysfunction, inflammatory response, and oxidative stress induced by PA via improving autophagic signaling. Lastly, employing c-Jun amino-terminal kinas (JNK), P38, or extracellular-regulated kinase (ERK) inhibitors, we established that the JNK and P38 MAPK pathways were involved in the MKP-5-mediated apoptosis, dysfunction, and autophagic inhibition observed in islet β cells in response to lipotoxicity.

Protective effect of Andrographolide on 5-Fu induced intestinal mucositis by regulating p38 MAPK signaling pathway

AIMS

Intestinal mucositis is the most common side effect of 5-fluorouracil (5-Fu) treatment in cancer patients. Previous research suggested that andrographolide (Andro) attenuated the intestinal injury in colitis or diarrhea in mice. The present study was aimed at investigating the protective effect of Andro against 5-Fu induced intestinal mucositis and the underlying mechanism.

MAIN METHODS

BALB/C mice were injected 5-Fu at a dose of 100 mg/kg for 5 days to induce intestinal mucositis. Andro at different doses (25, 50, 100 mg/kg/day) was administered. Weight loss, diarrhea score, cellular apoptosis and proliferation were evaluated. Apoptosis related proteins were detected by Western blotting. Then, NCM460 cells were used to explore the possible mechanism in vitro. The effect of Andro on the anti-tumor efficacy of 5-Fu was investigated in H22 tumor-bearing mice.

KEY FINDINGS

Andro significantly ameliorated the 5-Fu induced weight loss and diarrhea. The apoptosis of intestinal cells was also attenuated by Andro treatment both in vivo and in vitro. Besides, Andro markedly down-regulated the 5-Fu-induced protein expression of caspase8/3, Bax and the phosphorylation of p38. Moreover, 5-Fu significantly reduced the viability of NCM460 cells, which was restored by the Andro pretreatment. Furthermore, asiatic acid, an agonist of p38 MAPK, reversed the anti-apoptotic effect of Andro in NCM460 cells. Andro did not weaken the anti-H22 tumor effect of 5-Fu in vivo.

SIGNIFICANCE

We have demonstrated that p38 MAPK inhibition mediates anti-apoptotic effects of Andro against 5-Fu induced intestinal mucositis, suggesting that Andro may benefit the patients undergoing 5-Fu based chemotherapy.

Natriuretic Peptides Attenuate Retinal Pathological Neovascularization Via Cyclic Guanosine Monophosphate Signaling in Pericytes and Astrocytes

OBJECTIVE

In proliferative retinopathies, complications derived from neovascularization cause blindness. During early disease, pericyte's apoptosis contributes to endothelial dysfunction and leakage. Hypoxia then drives VEGF (vascular endothelial growth factor) secretion and pathological neoangiogenesis. Cardiac ANP (atrial natriuretic peptide) contributes to systemic microcirculatory homeostasis. ANP is also formed in the retina, with unclear functions. Here, we characterized whether endogenously formed ANP regulates retinal (neo)angiogenesis. Approach and Results: Retinal vascular development and ischemia-driven neovascularization were studied in mice with global deletion of GC-A (guanylyl cyclase-A), the cGMP (cyclic guanosine monophosphate)-forming ANP receptor. Mice with a floxed GC-A gene were interbred with Tie2-Cre, GFAP-Cre, or PDGF-Rβ-Cre^ERT2 lines to dissect the endothelial, astrocyte versus pericyte-mediated actions of ANP in vivo. In neonates with global GC-A deletion (KO), vascular development was mildly delayed. Moreover, such KO mice showed augmented vascular regression and exacerbated ischemia-driven neovascularization in the model of oxygen-induced retinopathy. Notably, absence of GC-A in endothelial cells did not impact retinal vascular development or pathological neovascularization. In vitro ANP/GC-A/cGMP signaling, via activation of cGMP-dependent protein kinase I, inhibited hypoxia-driven astrocyte's VEGF secretion and TGF-β (transforming growth factor beta)-induced pericyte apoptosis. In neonates lacking ANP/GC-A signaling in astrocytes, vascular development and hyperoxia-driven vascular regression were unaltered; ischemia-induced neovascularization was modestly increased. Remarkably, inactivation of GC-A in pericytes retarded physiological retinal vascularization and markedly enhanced cell apoptosis, vascular regression, and subsequent neovascularization in oxygen-induced retinopathy.

CONCLUSIONS

Protective pericyte effects of the ANP/GC-A/cGMP pathway counterregulate the initiation and progression of experimental proliferative retinopathy. Our observations indicate augmentation of endogenous pericyte ANP signaling as target for treatment of retinopathies associated with neovascularization.

The Dual-Specificity Phosphatase 10 (DUSP10): Its Role in Cancer, Inflammation, and Immunity

Cancer is one of the most diagnosed diseases in developed countries. Inflammation is a common response to different stress situations including cancer and infection. In those processes, the family of mitogen-activated protein kinases (MAPKs) has an important role regulating cytokine secretion, proliferation, survival, and apoptosis, among others. MAPKs regulate a large number of extracellular signals upon a variety of physiological as well as pathological conditions. MAPKs activation is tightly regulated by phosphorylation/dephosphorylation events. In this regard, the dual-specificity phosphatase 10 (DUSP10) has been described as a MAPK phosphatase that negatively regulates p38 MAPK and c-Jun N-terminal kinase (JNK) in several cellular types and tissues. Several studies have proposed that extracellular signal-regulated kinase (ERK) can be also modulated by DUSP10. This suggests a complex role of DUSP10 on MAPKs regulation and, in consequence, its impact in a wide variety of responses involved in both cancer and inflammation. Here, we review DUSP10 function in cancerous and immune cells and studies in both mouse models and patients that establish a clear role of DUSP10 in different processes such as inflammation, immunity, and cancer.