scholarly journals Sirtuins and SIRT6 in Carcinogenesis and in Diet

2019 ◽  
Vol 20 (19) ◽  
pp. 4945 ◽  
Author(s):  
de Céu Teixeira ◽  
Sanchez-Lopez ◽  
Espina ◽  
Garcia ◽  
Durazzo ◽  
...  
Keyword(s):  
Genome Stability ◽  
Energy Homeostasis ◽  
Tumor Development ◽  
Specific Treatment ◽  
Physiological Processes ◽  
Cancer Nanomedicine ◽  
Important Regulator ◽  
Dependent Protein ◽  
Development And Aging

Sirtuins are a highly conserved family of nicotinamide adenine dinucleotide (NAD)-dependent protein lysine modifying enzymes. They are key regulators for a wide variety of cellular and physiological processes such as cell proliferation, differentiation, DNA damage and stress response, genome stability, cell survival, metabolism, energy homeostasis, organ development and aging. Aging is one of the major risk factors of cancer, as many of the physiological mechanisms and pathologies associated with the aging process also contribute to tumor initiation, growth and/or metastasis. This review focuses on one the mammalian sirtuins, SIRT6, which has emerged as an important regulator of longevity and appears to have multiple biochemical functions that interfere with tumor development and may be useful in cancer prevention and for site-specific treatment. The recent evidence of the role of SIRT6 in carcinogenesis is also discussed, focusing on the potential use of SIRT6 modulators in cancer nanomedicine.

scholarly journals SIRT7 is a deacetylase of N4-acetylcytidine on ribosomal RNA

2021 ◽  
Author(s):  
Chenzhong Xu ◽  
Jin Zhang ◽  
Jie Zhang ◽  
Baohua Liu
Keyword(s):  
Circadian Rhythms ◽  
Ribosomal Rna ◽  
Genome Stability ◽  
Rna Stability ◽  
Translation Efficiency ◽  
Dependent Protein ◽  
First Time ◽  
Protein Deacetylase

AbstractN-acetyltransferase 10 catalyzes RNA N4-acetylcytidine (ac4C) modifications and thus regulates RNA stability and translation efficiency. However, the deacetylase for ac4C is unknown. SIRT7 was initially identified as an NAD+-dependent protein deacetylase and plays essential roles in genome stability, circadian rhythms, metabolism, and aging. In this study, we identified SIRT7 as a deacetylase of the ac4C of ribosomal (r)RNA for the first time and found it to be NAD+-independent. Our data highlight the important role of SIRT7 in rRNA ac4C modification and suggest an additional epitranscriptional regulation of aging.

scholarly journals Peroxisome Proliferator-Activated Receptor γ and PGC-1α in Cancer: Dual Actions as Tumor Promoter and Suppressor

PPAR Research ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Seong-Hoon Yun ◽  
Sang-Heum Han ◽  
Joo-In Park
Keyword(s):  
Metabolic Pathways ◽  
Energy Homeostasis ◽  
Tumor Promoter ◽  
Clinical Implications ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Interacting Protein ◽  
Action Mechanisms ◽  
Important Regulator

Peroxisome proliferator-activated receptor γ (PPARγ) is part of a nuclear receptor superfamily that regulates gene expression involved in cell differentiation, proliferation, immune/inflammation response, and lipid metabolism. PPARγ coactivator-1α (PGC-1α), initially identified as a PPARγ-interacting protein, is an important regulator of diverse metabolic pathways, such as oxidative metabolism and energy homeostasis. The role of PGC-1α in diabetes, neurodegeneration, and cardiovascular disease is particularly well known. PGC-1α is also now known to play important roles in cancer, independent of the role of PPARγ in cancer. Though many researchers have studied the expression and clinical implications of PPARγ and PGC-1α in cancer, there are still many controversies about the role of PPARγ and PGC-1α in cancer. This review examines and summarizes some recent data on the role and action mechanisms of PPARγ and PGC-1α in cancer, respectively, particularly the recent progress in understanding the role of PPARγ in several cancers since our review was published in 2012.

scholarly journals Role of N-Linked Glycosylation in PKR2 Trafficking and Signaling

2021 ◽  
Vol 15 ◽  
Author(s):  
Jissele A. Verdinez ◽  
Julien A. Sebag
Keyword(s):  
Plasma Membrane ◽  
Energy Homeostasis ◽  
Reproductive Function ◽  
Receptor Trafficking ◽  
Membrane Localization ◽  
Accessory Protein ◽  
Post Translational Modification ◽  
Physiological Processes ◽  
Glycosylation Sites

Prokineticin receptors are GPCRs involved in several physiological processes including the regulation of energy homeostasis, nociception, and reproductive function. PKRs are inhibited by the endogenous accessory protein MRAP2 which prevents them from trafficking to the plasma membrane. Very little is known about the importance of post-translational modification of PKRs and their role in receptor trafficking and signaling. Here we identify 2 N-linked glycosylation sites within the N-terminal region of PKR2 and demonstrate that glycosylation of PKR2 at position 27 is important for its plasma membrane localization and signaling. Additionally, we show that glycosylation at position 7 results in a decrease in PKR2 signaling through Gαs without impairing Gαq/11 signaling.

ZEB1 Promotes Chemoresistance to Cisplatin in Ovarian Cancer Cells by Suppressing SLC3A2

Chemotherapy ◽  
2018 ◽  
Vol 63 (5) ◽  
pp. 262-271 ◽  
Author(s):  
Yajie Cui ◽  
Li Qin ◽  
Defu Tian ◽  
Ting Wang ◽  
Lijing Fan ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cell Viability ◽  
Cancer Cells ◽  
Tumor Development ◽  
Migration And Invasion ◽  
Ovarian Cancer Cells ◽  
Cell Surface Molecule ◽  
Important Regulator ◽  
Induced Apoptosis

Ovarian cancer is one of the deadliest gynecological malignancies in women. Chemoresistance has been a major obstacle for ovarian cancer treatment. Zinc finger E-box-binding homeobox 1 (ZEB1) is an important regulator of tumor development in various types of cancer. Abnormal expression of SLC3A2 (CD98hc), a type 2 transmembrane cell surface molecule, has been described in several cancers. This study was designed to investigate the role of ZEB1 and SLC3A2 in the chemoresistance to cisplatin in ovarian cancer cells. We found that ZEB1 was increased in cisplatin-resistant SKOV3/DPP cells. Downregulation of ZEB1 significantly decreased cell viability in response to cisplatin, increased cis­platin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. In addition, downregulation of ZEB1 decreased the volume and weight of implanted tumors. SLC3A2 was decreased in cisplatin-resistant SKOV3/DPP cells. Upregulation of SLC3A2 significantly decreased cell viability in response to cisplatin, increased cisplatin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. Moreover, upregulation of SLC3A2 decreased the volume and weight of implanted tumors. Downregulation of ZEB1 resulted in a significant increase of SLC3A2 expression. Moreover, downregulation of SLC3A2 significantly inhibited ZEB1 knockdown-mediated inhibition of cisplatin-resistance. ZEB1-mediated regulation of SLC3A2 was involved in the chemoresistance to cisplatin in ovarian cancer cells. Overall, we provide new insights into the mechanism of chemoresistance to cisplatin in ovarian cancer cells. ZEB1/SLC3A2 may be promising therapeutic targets for enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy.

scholarly journals mTOR Pathway is Involved in Energy Homeostasis Regulation as a Part of the Gut–Brain Axis

2020 ◽  
Vol 21 (16) ◽  
pp. 5715
Author(s):  
Veronica Pena-Leon ◽  
Raquel Perez-Lois ◽  
Luisa Maria Seoane
Keyword(s):  
Energy Homeostasis ◽  
The Body ◽  
Mtor Signaling ◽  
Physiological Processes ◽  
Energy Sensor ◽  
Relevant Role ◽  
Regulate Food Intake ◽  
Glucose And Lipid Homeostasis ◽  
Treatment Of Obesity

Mammalian, or mechanic, target of rapamycin (mTOR) signaling is a crucial factor in the regulation of the energy balance that functions as an energy sensor in the body. The present review explores how the mTOR/S6k intracellular pathway is involved in modulating the production of different signals such as ghrelin and nesfatin-1 in the gastrointestinal tract to regulate food intake and body weight. The role of gastric mTOR signaling in different physiological processes was studied in depth through different genetic models that allow the modulation of mTOR signaling in the stomach and specifically in gastric X/A type cells. It has been described that mTOR signaling in X/A-like gastric cells has a relevant role in the regulation of glucose and lipid homeostasis due to its interaction with different organs such as liver and adipose tissue. These findings highlight possible therapeutic strategies, with the gut–brain axis being one of the most promising targets in the treatment of obesity.

Mitochondria: a possible nexus for the regulation of energy homeostasis by the endocannabinoid system?

2014 ◽  
Vol 307 (1) ◽  
pp. E1-E13 ◽  
Author(s):  
Christopher Lipina ◽  
Andrew J. Irving ◽  
Harinder S. Hundal
Keyword(s):  
Energy Homeostasis ◽  
Endocannabinoid System ◽  
Oxidative Capacity ◽  
Current Evidence ◽  
Peripheral Insulin Resistance ◽  
Physiological Processes ◽  
Peripheral Stimulation ◽  
The Metabolic Syndrome ◽  
Lipid Utilization

The endocannabinoid system (ECS) regulates numerous cellular and physiological processes through the activation of receptors targeted by endogenously produced ligands called endocannabinoids. Importantly, this signaling system is known to play an important role in modulating energy balance and glucose homeostasis. For example, current evidence indicates that the ECS becomes overactive during obesity whereby its central and peripheral stimulation drives metabolic processes that mimic the metabolic syndrome. Herein, we examine the role of the ECS in modulating the function of mitochondria, which play a pivotal role in maintaining cellular and systemic energy homeostasis, in large part due to their ability to tightly coordinate glucose and lipid utilization. Because of this, mitochondrial dysfunction is often associated with peripheral insulin resistance and glucose intolerance as well as the manifestation of excess lipid accumulation in the obese state. This review aims to highlight the different ways through which the ECS may impact upon mitochondrial abundance and/or oxidative capacity and, where possible, relate these findings to obesity-induced perturbations in metabolic function. Furthermore, we explore the potential implications of these findings in terms of the pathogenesis of metabolic disorders and how these may be used to strategically develop therapies targeting the ECS.

Chronic intracerebroventricular infusion of MCH causes obesity in mice

2003 ◽  
Vol 284 (3) ◽  
pp. E583-E588 ◽  
Author(s):  
Akira Gomori ◽  
Akane Ishihara ◽  
Masahiko Ito ◽  
Satoshi Mashiko ◽  
Hiroko Matsushita ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Control ◽  
Energy Homeostasis ◽  
The Body ◽  
Intracerebroventricular Infusion ◽  
Melanin Concentrating Hormone ◽  
Important Regulator ◽  
Obesity In Mice ◽  
Body Weight Control

Melanin-concentrating hormone (MCH) is a cyclic amino acid neuropeptide localized in the lateral hypothalamus. Although MCH is thought to be an important regulator of feeding behavior, the involvement of this peptide in body weight control has been unclear. To examine the role of MCH in the development of obesity, we assessed the effect of chronic intracerebroventricular infusion of MCH in C57BL/6J mice that were fed with regular or moderately high-fat (MHF) diets. Intracerebroventricular infusion of MCH (10 μg/day for 14 days) caused a slight but significant increase in body weight in mice maintained on the regular diet. In the MHF diet-fed mice, MCH more clearly increased the body weight accompanied by a sustained hyperphagia and significant increase in fat and liver weights. Plasma glucose, insulin, and leptin levels were also increased in the MCH-treated mice fed the MHF diet. These results suggest that chronic stimulation of the brain MCH system causes obesity in mice and imply that MCH may have a major role in energy homeostasis.

scholarly journals Sensing R-Loop-Associated DNA Damage to Safeguard Genome Stability

2021 ◽  
Vol 8 ◽  
Author(s):  
Carlo Rinaldi ◽  
Paolo Pizzul ◽  
Maria Pia Longhese ◽  
Diego Bonetti
Keyword(s):  
Dna Damage ◽  
Cellular Response ◽  
Genome Stability ◽  
Genome Instability ◽  
Hybrid Structure ◽  
Physiological Processes ◽  
Dna Strand ◽  
Template Dna ◽  
Dna Substrate

DNA transcription and replication are two essential physiological processes that can turn into a threat for genome integrity when they compete for the same DNA substrate. During transcription, the nascent RNA strongly binds the template DNA strand, leading to the formation of a peculiar RNA–DNA hybrid structure that displaces the non-template single-stranded DNA. This three-stranded nucleic acid transition is called R-loop. Although a programed formation of R-loops plays important physiological functions, these structures can turn into sources of DNA damage and genome instability when their homeostasis is altered. Indeed, both R-loop level and distribution in the genome are tightly controlled, and the list of factors involved in these regulatory mechanisms is continuously growing. Over the last years, our knowledge of R-loop homeostasis regulation (formation, stabilization, and resolution) has definitely increased. However, how R-loops affect genome stability and how the cellular response to their unscheduled formation is orchestrated are still not fully understood. In this review, we will report and discuss recent findings about these questions and we will focus on the role of ATM- and Rad3-related (ATR) and Ataxia–telangiectasia-mutated (ATM) kinases in the activation of an R-loop-dependent DNA damage response.

scholarly journals The ANXA2/S100A10 Complex—Regulation of the Oncogenic Plasminogen Receptor

Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1772
Author(s):  
Alamelu G. Bharadwaj ◽  
Emma Kempster ◽  
David M. Waisman
Keyword(s):  
Cell Surface ◽  
Cancer Cells ◽  
Proteolytic Activity ◽  
Cancer Progression ◽  
Tumor Development ◽  
Surface Receptors ◽  
Diagnosis And Prognosis ◽  
Physiological Processes ◽  
Complex Regulation

The generation of the serine protease plasmin is initiated by the binding of its zymogenic precursor, plasminogen, to cell surface receptors. The proteolytic activity of plasmin, generated at the cell surface, plays a crucial role in several physiological processes, including fibrinolysis, angiogenesis, wound healing, and the invasion of cells through both the basement membrane and extracellular matrix. The seminal observation by Albert Fischer that cancer cells, but not normal cells in culture, produce large amounts of plasmin formed the basis of current-day observations that plasmin generation can be hijacked by cancer cells to allow tumor development, progression, and metastasis. Thus, the cell surface plasminogen-binding receptor proteins are critical to generating plasmin proteolytic activity at the cell surface. This review focuses on one of the twelve well-described plasminogen receptors, S100A10, which, when in complex with its regulatory partner, annexin A2 (ANXA2), forms the ANXA2/S100A10 heterotetrameric complex referred to as AIIt. We present the theme that AIIt is the quintessential cellular plasminogen receptor since it regulates the formation and the destruction of plasmin. We also introduce the term oncogenic plasminogen receptor to define those plasminogen receptors directly activated during cancer progression. We then discuss the research establishing AIIt as an oncogenic plasminogen receptor-regulated during EMT and activated by oncogenes such as SRC, RAS, HIF1α, and PML-RAR and epigenetically by DNA methylation. We further discuss the evidence derived from animal models supporting the role of S100A10 in tumor progression and oncogenesis. Lastly, we describe the potential of S100A10 as a biomarker for cancer diagnosis and prognosis.

scholarly journals Functional Characterization of Melanocortin-3 Receptor In Rainbow Trout (Oncorhynchus Mykiss)

2021 ◽  
Author(s):  
Hui-Xia Yu ◽  
Yang Li ◽  
Wei-Jia Song ◽  
Hui Wang ◽  
Hao-Lin Mo ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Energy Homeostasis ◽  
Functional Characterization ◽  
Luciferase Reporter ◽  
Intracellular Camp ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Bony Fishes ◽  
Important Regulator ◽  
Reporter Assays

Abstract The melanocortin-3 receptor (MC3R) is an important regulator of energy homeostasis and inflammation in mammals. However, its function in teleost fish needs to be further explored. In this study, we characterized rainbow trout MC3R (rtMC3R), which encoded a putative protein of 331 amino acids. Phylogenetic and chromosomal synteny analyses showed that rtMC3R was closely related to bony fishes. Quantitative PCR (qPCR) revealed that the transcripts of rtMC3R were highly expressed in the brain and muscle. The cellular function of rtMC3R was further verified by the signal-pathway-specific luciferase reporter assays. Four agonists such as α-MSH, β-MSH, ACTH (1–24) and NDP-MSH can active rtMC3R, increasing the production of intracellular cAMP and up-regulating MAPK/ERK signals. Moreover, we found that rtMC3R stimulated with α-MSH and NDP-MSH can significantly inhibit the NF-κB signaling pathway. This research will be helpful for further studies on the function of MC3R in rainbow trout, especially the role of energy metabolism and immune regulation.

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