Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0276640 (TEM)
 20,729 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The current study aimed to examine the anticancer activity of HTF-1, a cardiac glycoside (CG) isolated from Helleborus thibetanus Franch, using a cell-based model and to discover the underlying mechanisms with specific focus on autophagy. We found that HTF-1 was able to potently decrease the viability of several cancer cell lines especially for HeLa cervical carcinoma cells. It was discovered that HTF-1 dose dependently induced overproduction of ROS in HeLa cells, and the cell viability can be rescued when adding ROS scavenger N-acetyl-l-cysteine (NAC). More, we found that HTF-1 induced ROS-independent autophagy in concentration- and time-dependent manners in HeLa cells. This can be collectively verified by LC3-II and p62 abundance and also eGFP-LC3 puncta assay, bafilomycin clamp experiment, and acidotropic dye fluorescent labeling experiment. Additionally, TEM examination showed more autophagic vacuoles for HTF-1-treated HeLa cells. In HeLa cells, pretreatment with wortmannin (an inhibitor of the initial stages of autophagy to block autophagosome formation, thus, it should weaken the autophagy induction effect of HTF-1) decreased the autophagic flux and partially antagonized cell death induced by HTF-1, indicating that autophagy induced by HTF-1 played a cancer-suppressing role. Furthermore, coadministration of BAF (as a distal inhibitor of autophagy) with HTF-1 demonstrated a synergistic anticancer effect against HeLa cells. We believe that our work will enrich the understanding of CGs and especially anticarcinoma activity, also, pave the way for natural-product-based anticancer drug development.
 ...
PMID:Cardiac Glycoside Compound Isolated from Helleborus thibetanus Franch Displays Potent Toxicity against HeLa Cervical Carcinoma Cells through ROS-Independent Autophagy. 3171 69

Mitochondria operate as a central hub for many metabolic processes by sensing and responding to the cellular environment. Developmental cues from the environment have been implicated in selective autophagy, or mitophagy, of mitochondria during cell differentiation and tissue development. Mitophagy occurring in this context, termed programmed mitophagy, responds to cell state rather than mitochondrial damage and is often accompanied by a metabolic transition. However, little is known about the mechanisms that engage and execute mitophagy under physiological or developmental conditions. As the mammary gland undergoes post-natal development and lactation challenges mitochondrial homeostasis, we investigated the contribution of mitochondria to differentiation of mammary epithelial cells (MECs). Using lactogenic differentiation of the HC11 mouse MEC line, we demonstrated that HC11 cells transition to a highly energetic state during differentiation by engaging both oxidative phosphorylation and glycolysis. Interestingly, this transition was lost when autophagy was inhibited with bafilomycin A1 or knockdown of Atg7 (autophagy related 7). To evaluate the specific targeting of mitochondria, we traced mitochondrial oxidation and turnover in vitro with the fluorescent probe, pMitoTimer. Indeed, we found that differentiation engaged mitophagy. To further evaluate the requirement of mitophagy during differentiation, we knocked down the expression of Prkn/parkin in HC11 cells. We found that MEC differentiation was impaired in shPrkn cells, implying that PRKN is required for MEC differentiation. These studies suggest a novel regulation of MEC differentiation through programmed mitophagy and provide a foundation for future studies of development and disease associated with mitochondrial function in the mammary gland.Abbreviations: AA: antimycin A; ATG5: autophagy related 5; BAF: bafilomycin A1; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; COX8A: cytochrome c oxidase subunit 8A; CQ: chloroquine; CSN2: casein beta; ECAR: extracellular acidification rate; FCCP: trifluoromethoxy carbonylcyanide phenylhydrazone; FUNDC1: FUN14 domain containing 1; HIF1A: hypoxia inducible factor 1 subunit alpha; L1: lactation day 1; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MEC: mammary epithelial cell; mitoQ: mitoquinol; mROS: mitochondrial reactive oxygen species; OCR: oxygen consumption rate; P: priming; P16: pregnancy day 16; PARP1: poly(ADP-ribose) polymerase 1; PINK1: PTEN induced kinase 1; PPARGC1A: PPARG coactivator 1 alpha; PRKN: parkin RBR E3 ubiquitin protein ligase; shNT: short hairpin non-targeting control; SQSTM1: sequestosome 1; STAT3: signal transducer and activator of transcription 3; TEM: transmission electron microscopy; TFAM: transcription factor A, mitochondrial; U: undifferentiated.
 ...
PMID:Autophagy regulates functional differentiation of mammary epithelial cells. 3198 67

Autophagic flux is a critical cellular process that is vastly under-appreciated in terms of its importance to human health. Preclinical studies have demonstrated that reductions in autophagic flux cause cancer and exacerbate chronic diseases, including heart disease and the pathological hallmarks of dementia. Autophagic flux can be increased by targeting nutrition-related biochemical signaling. To date, translation of this knowledge has been hampered because there has been no way to directly measure autophagic flux in humans. In this study we detail a method whereby human macroautophagic/autophagic flux can be directly measured from human blood samples. We show that whole blood samples can be treated with the lysosomal inhibitor chloroquine, and peripheral blood mononuclear cells isolated from these samples could be used to measure autophagic machinery protein LC3B-II. Blocking of autophagic flux in cells while still in whole blood represents an important advance because it preserves genetic, nutritional, and signaling parameters inherent to the individual. We show this method was reproducible and defined LC3B-II as the best protein to measure autophagic flux in these cells. Finally, we show that this method is relevant to assess intra-individual variation induced by an intervention by manipulating nutrition signaling with an ex vivo treatment of whole blood that comprised leucine and insulin. Significantly, this method will enable the identification of factors that alter autophagic flux in humans, and better aid their translation in the clinic. With further research, it could also be used as a novel biomarker for risk of age-related chronic disease. Abbreviations:AMPK: AMP-activated protein kinase; ACTB: actin beta; ATG5: autophagy related 5; BAF: bafilomycin A1; CQ: chloroquine; DMSO: dimethyl sulfoxide; DPBS: Dulbecco's phosphate-buffered saline; EDTA: ethylenediaminetetraacetic acid; KO: knockout; MAP1LC3A/LC3A: microtubule associated protein 1 light chain 3 alpha; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAP1LC3C/LC3C: microtubule associated protein 1 light chain 3 gamma; MTOR: mechanistic target of rapamycin kinase; NBR1: NBR1 autophagy cargo receptor; PBMCs: peripheral blood mononuclear cells; PMNs: polymorphonuclear cells; RPMI: Roswell Park Memorial Institute; SQSTM1: sequestosome 1; TBST: Tris-buffered saline containing 0.1% (v:v) Tween 20; TEM: transmission electron microscopy.
 ...
PMID:Measurement of autophagic flux in humans: an optimized method for blood samples. 3316 41