Cardiomyocyte death is an important pathogenic feature of ischemia and heart failure. Through this study, we showed the synergistic role of HIF‐1α and FoxO3a in cardiomyocyte apoptosis subjected to hypoxia plus elevated glucose levels. Using gene specific small interfering RNAs (siRNA), semi‐quantitative reverse transcriptase polymerase chain reaction (RT‐PCR), Western blot, immunofluorescence, nuclear and cytosolic localization and TUNEL assay techniques, we determined that combined function of HIF‐1α and FoxO3a under high glucose plus hypoxia condition lead to enhanced expression of BNIP3 inducing cardiomyocyte death. Our results highlighted the importance of the synergistic role of HIF‐1α and FoxO3a in cardiomyocyte death which may add insight into therapeutic approaches to pathophysiology associated with ischemic diabetic cardiomyopathies.
Phospholipases (PLAs) constitute a pervasive class of enzymes that hydrolyze phospholipids into fatty acids and other lipophilic substances. PLAs through their enzymatic activity are known to play an important role in various cell signaling events such as cell migration, apoptosis, reactive oxygen species generation, proliferation and differentiation, cancer, killing pathogenic bacteria, or modulating inflammatory responses. They are endowed with varied structural diversity, enzymatic properties and tissue distribution in humans. Deregulation in these cellular processes lead to abnormalities in cell physiological responses that culminate into varied forms of human cancers. Abnormalities in the expression and activity of several phospholipases have been observed in human cancers of varied tissue types. In this review, we summarize the phospholipase family and the recent evidences pertaining to role of secretory phospholipase A2 (sPLA2) in human cancers.
Coenzyme Q0 (CoQ0), a quinone derivative from Antrodia camphorata, has antitumor capabilities.This study investigated the antitumor effect of noncytotoxic CoQ0, which included NLRP3 inflammasome inhibition, anti-EMT/metastasis, and metabolic reprogramming via HIF-1α inhibition, in HNSCC cells under normoxia and hypoxia.CoQ0 suppressed hypoxia-induced ROS-mediated HIF-1α expression in OECM-1 and SAS cells.Under normoxia and hypoxia, the inflammatory NLRP3, ASC/caspase-1, NFκB, and IL-1β expression was reduced by CoQ0.CoQ0 reduced migration/invasion by enhancing epithelial marker E-cadherin and suppressing mesenchymal markers Twist, N-cadherin, Snail, and MMP-9, and MMP-2 expression.CoQ0 inhibited glucose uptake, lactate accumulation, GLUT1 levels, and HIF-1α-target gene (HK-2, PFK-1, and LDH-A) expressions that are involved in aerobic glycolysis.Notably, CoQ0 reduced ECAR as well as glycolysis, glycolytic capability, and glycolytic reserve and enhanced OCR, basal respiration, ATP generation, maximal respiration, and spare capacity in OECM-1 cells.Metabolomic analysis using LC-ESI-MS showed that CoQ0 treatment decreased the levels of glycolytic intermediates, including lactate, 2/3-phosphoglycerate, fructose 1,6-bisphosphate, and phosphoenolpyruvate, and increased the levels of TCA cycle metabolites, including citrate, isocitrate, and succinate.HIF-1α silencing reversed CoQ0-mediated anti-metastasis (N-Cadherin, Snail, and MMP-9) and metabolic reprogramming (GLUT1, HK-2, and PKM-2) under hypoxia.CoQ0 prevents cancer stem-like characteristics (upregulated CD24 expression and downregulated CD44, ALDH1, and OCT4) under normoxia and/or hypoxia.Further, in IL-6-treated SG cells, CoQ0 attenuated fibrosis by inhibiting TGF-β and Collagen I expression and suppressed EMT by downregulating Slug and upregulating E-cadherin expression.Interesting, CoQ0 inhibited the growth of OECM-1 tumors in xenografted mice.Our results advocate CoQ0 for the therapeutic application against HNSCC.
Cardiovascular diseases have a high prevalence worldwide and constitute the leading causes of mortality. Recently, malfunctioning of β-catenin signaling has been addressed in hypertensive heart condition. Ang-II is an important mediator of cardiovascular remodeling processes which not only regulates blood pressure but also leads to pathological cardiac changes. However, the contribution of Ang-II/β-catenin axis in hypertrophied hearts is ill-defined. Employing in vitro H9c2 cells and in vivo spontaneously hypertensive rats (SHR) cardiac tissue samples, western blot analysis, luciferase assays, nuclear-cytosolic protein extracts, and immunoprecipitation assays, we found that under hypertensive condition β-catenin gets abnormally induced that co-activated LEF1 and lead to cardiac hypertrophy changes by up-regulating the IGF-IIR signaling pathway. We identified putative LEF1 consensus binding site on IGF-IIR promoter that could be regulated by β-catenin/LEF1 which in turn modulate the expression of cardiac hypertrophy agents. This study suggested that suppression of β-catenin expression under hypertensive condition could be exploited as a clinical strategy for cardiac pathological remodeling processes.
Patients with type two diabetes mellitus (T2DM) are at increased risk for cardiovascular diseases. Impairments of endothelin-1 (ET-1) signaling and mTOR pathway have been implicated in diabetic cardiomyopathies. However, the molecular interplay between the ET-1 and mTOR pathway under high glucose (HG) conditions in H9c2 cardiomyoblasts has not been investigated. We employed MTT assay, qPCR, western blotting, fluorescence assays, and confocal microscopy to assess the oxidative stress and mitochondrial damage under hyperglycemic conditions in H9c2 cells. Our results showed that HG-induced cellular stress leads to a significant decline in cell survival and an impairment in the activation of ETA-R/ETB-R and the mTOR main components, Raptor and Rictor. These changes induced by HG were accompanied by a reactive oxygen species (ROS) level increase and mitochondrial membrane potential (MMP) loss. In addition, the fragmentation of mitochondria and a decrease in mitochondrial size were observed. However, the inhibition of either ETA-R alone by ambrisentan or ETA-R/ETB-R by bosentan or the partial blockage of the mTOR function by silencing Raptor or Rictor counteracted those adverse effects on the cellular function. Altogether, our findings prove that ET-1 signaling under HG conditions leads to a significant mitochondrial dysfunction involving contributions from the mTOR pathway.
We assayed skin hydration and anti-inflammatory efficacies of zerumbone (Zer, 2.5–10 μM), a natural sesquiterpene of Zingiber zerumbet, using non– or UVB (30 mJ/cm2)-irradiated keratinocytes (HaCaT). & Zer increased cell viability, upregulated hyaluronic acid, and inhibited ROS generation in UVB-irradiated HaCaT cells. Zer promoted antioxidant Nrf2 nuclear translocation resulting in HO-1 and γ-GCLC expression. Zer promotes skin hyaluronic acid by increasing protein and mRNA expression of HAS-2 and AQP-3 in non– or UVB-irradiated HaCaT cells. Furthermore, Zer increased Src and ERK phosphorylation. Src silencing or ERK inhibitor (PD98059) diminished Zer-mediated skin hydration, as evidenced by decreased HAS-2 and AQP-3 expression. Interestingly, UVB-induced Src/ERK inhibition was reversed by Zer or N-acetylcysteine. Additionally, Zer inhibited inflammatory iNOS, COX-2, and IL-1β expression through NFκB (p65) and AP-1 (c-Jun/c-Fos) pathway in UVB-irradiated HaCaT cells. HaCaT cells treated with Zer enhanced the growth factors PDGF-A, VEGF, and EGFR expressions. Zerumbone might be utilized in cosmetic formulations.