scholarly journals Multiple Mechanisms Converging on Transcription Factor EB Activation by the Natural Phenol Pterostilbene

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Martina La Spina ◽  
Michele Azzolini ◽  
Andrea Salmaso ◽  
Sofia Parrasia ◽  
Eva Galletta ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Therapeutic Potential ◽  
Body Weight Gain ◽  
Mitochondrial Respiratory Chain ◽  
Reduced Body ◽  
Diet Induced Obesity ◽  
Activation Of Transcription ◽  
Transcription Factor Eb

Pterostilbene (Pt) is a potentially beneficial plant phenol. In contrast to many other natural compounds (including the more celebrated resveratrol), Pt concentrations producing significant effects in vitro can also be reached with relative ease in vivo. Here we focus on some of the mechanisms underlying its activity, those involved in the activation of transcription factor EB (TFEB). A set of processes leading to this outcome starts with the generation of ROS, attributed to the interaction of Pt with complex I of the mitochondrial respiratory chain, and spreads to involve Ca2+ mobilization from the ER/mitochondria pool, activation of CREB and AMPK, and inhibition of mTORC1. TFEB migration to the nucleus results in the upregulation of autophagy and lysosomal and mitochondrial biogenesis. Cells exposed to several μM levels of Pt experience a mitochondrial crisis, an indication for using low doses in therapeutic or nutraceutical applications. Pt afforded significant functional improvements in a zebrafish embryo model of ColVI-related myopathy, a pathology which also involves defective autophagy. Furthermore, long-term supplementation with Pt reduced body weight gain and increased transcription levels of Ppargc1a and Tfeb in a mouse model of diet-induced obesity. These in vivo findings strengthen the in vitro observations and highlight the therapeutic potential of this natural compound.

scholarly journals RIP3 impedes transcription factor EB to suppress autophagic degradation in septic acute kidney injury

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Ruizhao Li ◽  
Xingchen Zhao ◽  
Shu Zhang ◽  
Wei Dong ◽  
Li Zhang ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Transcription Factor ◽  
Nuclear Translocation ◽  
Kidney Injury ◽  
Septic Acute Kidney Injury ◽  
Transcription Factor Eb ◽  
Autophagic Degradation ◽  
Lps Treatment

AbstractAutophagy is an important renal-protective mechanism in septic acute kidney injury (AKI). Receptor interacting protein kinase 3 (RIP3) has been implicated in the renal tubular injury and renal dysfunction during septic AKI. Here we investigated the role and mechanism of RIP3 on autophagy in septic AKI. We showed an activation of RIP3, accompanied by an accumulation of the autophagosome marker LC3II and the autophagic substrate p62, in the kidneys of lipopolysaccharide (LPS)-induced septic AKI mice and LPS-treated cultured renal proximal tubular epithelial cells (PTECs). The lysosome inhibitor did not further increase the levels of LCII or p62 in LPS-treated PTECs. Moreover, inhibition of RIP3 attenuated the aberrant accumulation of LC3II and p62 under LPS treatment in vivo and in vitro. By utilizing mCherry-GFP-LC3 autophagy reporter mice in vivo and PTECs overexpression mRFP-GFP-LC3 in vitro, we observed that inhibition of RIP3 restored the formation of autolysosomes and eliminated the accumulated autophagosomes under LPS treatment. These results indicated that RIP3 impaired autophagic degradation, contributing to the accumulation of autophagosomes. Mechanistically, the nuclear translocation of transcription factor EB (TFEB), a master regulator of the lysosome and autophagy pathway, was inhibited in LPS-induced mice and LPS-treated PTECs. Inhibition of RIP3 restored the nuclear translocation of TFEB in vivo and in vitro. Co-immunoprecipitation further showed an interaction of RIP3 and TFEB in LPS-treated PTECs. Also, the expression of LAMP1 and cathepsin B, two potential target genes of TFEB involved in lysosome function, were decreased under LPS treatment in vivo and in vitro, and this decrease was rescued by inhibiting RIP3. Finally, overexpression of TFEB restored the autophagic degradation in LPS-treated PTECs. Together, the present study has identified a pivotal role of RIP3 in suppressing autophagic degradation through impeding the TFEB-lysosome pathway in septic AKI, providing potential therapeutic targets for the prevention and treatment of septic AKI.

scholarly journals Bauhiniastatin-1 alleviates diet induced obesity and lipid accumulation through modulating PPAR-γ/AMPK expressions: In-vitro, in-vivo and in-silico studies.

2021 ◽  
Author(s):  
Karunakaran Reddy Sankaran ◽  
Lokanatha Oruganti ◽  
Muni Swamy Ganjayi ◽  
Venkataramaiah Chintha ◽  
Muni Kesavulu Muppuru ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Western Blot ◽  
Blot Analysis ◽  
Body Weight Gain ◽  
Liver Lipid ◽  
Ppar Γ ◽  
Diet Induced Obesity

Abstract Background: Consumption of energy dense foods and sedentary lifestyles have led to high prevalence of obesity and associated disorders. Intensive research efforts have focussed to develop effective alternative therapeutics from plant sources. Bauhiniastatins have been reported to possess antineoplastic activity. In the present study, Bauhiniastatin-1 (BSTN1) was isolated and purified from Bauhinia purpurea and evaluated for its therapeutic efficacy against adipogenesis and obesity using high fat diet (HFD)-induced obese rodent model and 3T3-L1 cells.Methods: We performed in-vitro experiments like MTT assay, Oil Red O (ORO) stain, cellular lipid content, glycerol release and RT-PCR analysis in 3T3-L1 cells. In-vivo parameters like body weight gain, body composition, plasma adipokines, serum & liver lipid profiles, liver marker enzymes, western blot analysis and histopathological examination were conducted in rat model. In addition, molecular docking studies were also performed to understand interaction of BSTN1 with peroxisome proliferator-activated gamma receptor (PPAR-γ) and AMP-activated protein kinase (AMPK) which supported our experimental results.Results: BSTN1 at 20 μM significantly (p<0.001) inhibited cell differentiation and lipid accumulation of 3T3-L1 adipocytes. Mechanistic studies showed that mRNA expression of key adipogenic markers, PPAR-γ, fatty acid synthase (FAS) and sterol-regulatory element-binding protein-1 (SREBP1) were down-regulated while AMPK was up-regulated by BSTN1. Oral administration of BSTN1 (5 mg/kg. b.wt.) to HFD-induced obese rats substantially decreased body weight gain, fat mass, serum and liver lipid levels and promoted integrity of hepatic and adipose tissue architecture compared to HFD-control rats. In BSTN1 administered groups, decreased serum aspartate transaminase (AST) and alanine aminotransferase (ALT) levels, decreased plasma leptin but increased adiponectin levels were noted. Western blot analysis of adipose and hepatic tissues collected from BSTN1 treated rats showed decreased expression level of PPAR-γ but increase in AMPK expression relative to the untreated group. In-silico studies showed strong binding interactions of BSTN1 against PPAR-γ and AMPK, the key molecules of adipogenesis and obesity.Conclusions: Taken together, the results suggest that BSTN1 could be promising molecule for the treatment of diet-induced obesity and non-alcoholic fatty liver disease (NAFLD).

scholarly journals D-allulose ameliorates adiposity through the AMPK-SIRT1-PGC-1α pathway in HFD-induced SD rats

2021 ◽  
Author(s):  
Geum Hwa Lee ◽  
Cheng Peng ◽  
Hwa-Young Lee ◽  
Seon-Ah Park ◽  
The-Hiep Hoang ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Body Weight Gain ◽  
Chow Diet ◽  
Metabolic Dysfunction ◽  
Sprague Dawley ◽  
Metabolic Disturbances ◽  
Beneficial Effects ◽  
Reduced Body

Background: Adiposity is a major health-risk factor, and D-allulose has beneficial effects on adiposity-related metabolic disturbances. However, the modes of action underlying anti-hyperglycemic and hypolipidemic activity are partly understood. Objective: This study investigated the in vivo and in vitro effects of D-allulose involved in adipogenesis and activation of the AMPK/SIRT1/PGC-1α pathway in high-fat diet (HFD)-fed rats. Design: In this study, 8-week-old male SD (Sprague Dawley) rats were divided into five groups (n = 8/group), (1) Control (chow diet, 3.5%); (2) 60% HFD; (3) 60% HFD supplemented with allulose powder (AP) at 0.4 g/kg; (4) 60% HFD supplemented with allulose liquid (AL) at 0.4 g/kg; (5) 60% HFD supplemented with glucose (AL) at 0.4 g/kg. All the group received the product through oral gavage for 6 weeks. Control and HFD groups were gavaged with double-distilled water. Results: Rats receiving AP and AL showed reduced body weight gain and fat accumulation in HFD-fed rats. Also, supplementation of AL/AP regulated the cytokine secretion and recovered biochemical parameters to alleviate metabolic dysfunction and hepatic injury. Additionally, AL/AP administration improved adipocyte differentiation via regulation of the PPARγ and C/EBPα signaling pathway and adipogenesis-related genes owing to the combined effect of the AMPK/SIRT1 pathway. Furthermore, AL/AP treatment mediated PGC-1α expression triggering mitochondrial genesis via activating the AMPK phosphorylation and SIRT1 deacetylation activity in adipose tissue. Conclusion: The anti-adiposity activity of D-allulose is observed on a marked alleviation in adipogenesis and AMPK/SIRT1/PGC-1α deacetylation in the adipose tissue of HFD-fed rat.

scholarly journals Multiple Selection Criteria for Probiotic Strains with High Potential for Obesity Management

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 713
Author(s):  
Jeanne Alard ◽  
Benoit Cudennec ◽  
Denise Boutillier ◽  
Véronique Peucelle ◽  
Amandine Descat ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Leptin Receptor ◽  
Body Weight Gain ◽  
Bifidobacterium Longum ◽  
Protective Effects ◽  
Metabolic Dysfunction ◽  
Diet Induced Obesity ◽  
Probiotic Strains

Since alterations of the gut microbiota have been shown to play a major role in obesity, probiotics have attracted attention. Our aim was to identify probiotic candidates for the management of obesity using a combination of in vitro and in vivo approaches. We evaluated in vitro the ability of 23 strains to limit lipid accumulation in adipocytes and to enhance the secretion of satiety-promoting gut peptide in enteroendocrine cells. Following the in vitro screening, selected strains were further investigated in vivo, single, or as mixtures, using a murine model of diet-induced obesity. Strain Bifidobacterium longum PI10 administrated alone and the mixture of B. animalis subsp. lactis LA804 and Lactobacillus gasseri LA806 limited body weight gain and reduced obesity-associated metabolic dysfunction and inflammation. These protective effects were associated with changes in the hypothalamic gene expression of leptin and leptin receptor as well as with changes in the composition of gut microbiota and the profile of bile acids. This study provides crucial clues to identify new potential probiotics as effective therapeutic approaches in the management of obesity, while also providing some insights into their mechanisms of action.

Doxorubicin impairs cardiomyocyte viability by suppressing transcription factor EB expression and disrupting autophagy

2016 ◽  
Vol 473 (21) ◽  
pp. 3769-3789 ◽  
Author(s):  
Jordan J. Bartlett ◽  
Purvi C. Trivedi ◽  
Pollen Yeung ◽  
Petra C. Kienesberger ◽  
Thomas Pulinilkunnil
Keyword(s):  
Cell Death ◽  
Transcription Factor ◽  
Cathepsin B ◽  
Ex Vivo ◽  
Calcium Flux ◽  
Autophagic Flux ◽  
Mitochondrial Energy Metabolism ◽  
Transcription Factor Eb

Doxorubicin (DOX) is an effective anti-cancer agent. However, DOX treatment increases patient susceptibility to dilated cardiomyopathy. DOX predisposes cardiomyocytes to insult by suppressing mitochondrial energy metabolism, altering calcium flux, and disrupting proteolysis and proteostasis. Prior studies have assessed the role of macroautophagy in DOX cardiotoxicity; however, limited studies have examined whether DOX mediates cardiac injury through dysfunctions in inter- and/or intra-lysosomal signaling events. Lysosomal signaling and function is governed by transcription factor EB (TFEB). In the present study, we hypothesized that DOX caused myocyte injury by impairing lysosomal function and signaling through negative regulation of TFEB. Indeed, we found that DOX repressed cellular TFEB expression, which was associated with impaired cathepsin proteolytic activity across in vivo, ex vivo, and in vitro models of DOX cardiotoxicity. Furthermore, we observed that loss of TFEB was associated with reduction in macroautophagy protein expression, inhibition of autophagic flux, impairments in lysosomal cathepsin B activity, and activation of cell death. Restoration and/or activation of TFEB in DOX-treated cardiomyocytes prevented DOX-induced suppression of cathepsin B activity, reduced DOX-mediated reactive oxygen species (ROS) overproduction, attenuated activation of caspase-3, and improved cellular viability. Collectively, loss of TFEB inhibits lysosomal autophagy, rendering cardiomyocytes susceptible to DOX-induced proteotoxicity and injury. Our data reveal a novel mechanism wherein DOX primes cardiomyocytes for cell death by depleting cellular TFEB.

scholarly journals Searching for Peptide Inhibitors of T Regulatory Cell Activity by Targeting Specific Domains of FOXP3 Transcription Factor

Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 197
Author(s):  
Teresa Lozano ◽  
Noelia Casares ◽  
Celia Martil-Otal ◽  
Blanca Anega ◽  
Marta Gorraiz ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Synthetic Peptides ◽  
Therapeutic Potential ◽  
Binding Capacity ◽  
Cell Activity ◽  
Antitumoral Activity ◽  
T Regulatory Cell

(1) Background: The ability of cancer cells to evade the immune system is due in part to their capacity to induce and recruit T regulatory cells (Tregs) to the tumor microenvironment. Strategies proposed to improve antitumor immunity by depleting Tregs generally lack specificity and raise the possibility of autoimmunity. Therefore, we propose to control Tregs by their functional inactivation rather than depletion. Tregs are characterized by the expression of the Forkhead box protein 3 (FOXP3) transcription factor, which is considered their “master regulator”. Its interaction with DNA is assisted primarily by its interaction with other proteins in the so-called “Foxp3 interactome”, which elicits much of the characteristic Treg cell transcriptional signature. We speculated that the disruption of such a protein complex by using synthetic peptides able to bind Foxp3 might have an impact on the functionality of Treg cells and thus have a therapeutic potential in cancer treatment. (2) Methods: By using a phage-displayed peptide library, or short synthetic peptides encompassing Foxp3 fragments, or by studying the crystal structure of the Foxp3:NFAT complex, we have identified a series of peptides that are able to bind Foxp3 and inhibit Treg activity. (3) Results: We identified some peptides encompassing fragments of the leuzin zipper or the C terminal domain of Foxp3 with the capacity to inhibit Treg activity in vitro. The acetylation/amidation of linear peptides, head-to-tail cyclization, the incorporation of non-natural aminoacids, or the incorporation of cell-penetrating peptide motifs increased in some cases the Foxp3 binding capacity and Treg inhibitory activity of the identified peptides. Some of them have shown antitumoral activity in vivo. (4) Conclusions: Synthetic peptides constitute an alternative to inhibit Foxp3 protein–protein interactions intracellularly and impair Treg immunosuppressive activity. These peptides might be considered as potential hit compounds on the design of new immunotherapeutic approaches against cancer.

scholarly journals Transcription Factor Runx1 Activates Opn to Promote Tumor Progression in Head and Neck Cancer

2020 ◽  
Author(s):  
Kai Liu ◽  
Huiying Hu ◽  
Huanyu Jiang ◽  
Haidong Zhang ◽  
Shanchun Gong ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Head And Neck ◽  
Therapeutic Potential ◽  
Underlying Mechanism ◽  
Mapk Signaling ◽  
Luciferase Reporter ◽  
Metastatic Progression ◽  
Related Transcription Factor

Abstract Background:Metastatic progression remains a major burden for head and neck squamous cell carcinoma (HNSCC). Runt-related transcription factor 1 (RUNX1)has been reported to be associated with an aggressive phenotype in several cancers. However, the precise roles of RUNX1 underlying the metastaticprogression of HNSCC remain largely unknown.Methods:RUNX1 expression levels in HNSCC cells and tissues were detected by quantitative real-time PCR (qPCR), Western blottingand immunohistochemistry (IHC). In vitro and in vivo assays were performed to investigate the function of RUNX1 in the metastatic phenotype and the tumorigenic capability of HNSCC cells. Luciferase reporter and chromatin immunoprecipitation (ChIP)-qPCR assays were performed to determine the underlying mechanism of RUNX1-mediated HNSCC aggressiveness.Results:RUNX1 was increased with disease progression in patients withHNSCC.Furthermore, we found that silencing ofRUNX1 significantly decelerated the malignant progression of HNSCC cells and reduced Osteopontin (OPN) expression in vitro, and weakened the tumorigenicityof HNSCC cells in vivo. Mechanistically, we demonstrated that RUNX1 played an important role in activating MAPK signaling by directly binding to the promoter of OPN.Conclusions: Our results provide new insight into the mechanisms underlying the facilitate metastasisability of RUNX1and reveal the therapeutic potential of targeting RUNX1 in HNSCC.

scholarly journals The translocator protein (TSPO) is prodromal to mitophagy loss in neurotoxicity

2021 ◽  
Author(s):  
Michele Frison ◽  
Danilo Faccenda ◽  
Rosella Abeti ◽  
Manuel Rigon ◽  
Daniela Strobbe ◽  
...  
Keyword(s):  
Cell Death ◽  
Transcription Factor ◽  
Translocator Protein ◽  
Redox Stress ◽  
Cellular Redox ◽  
Extracellular Signal ◽  
Transcription Factor Eb ◽  
Stress Susceptibility

AbstractDysfunctional mitochondria characterise Parkinson’s Disease (PD). Uncovering etiological molecules, which harm the homeostasis of mitochondria in response to pathological cues, is therefore pivotal to inform early diagnosis and therapy in the condition, especially in its idiopathic forms. This study proposes the 18 kDa Translocator Protein (TSPO) to be one of those. Both in vitro and in vivo data show that neurotoxins, which phenotypically mimic PD, increase TSPO to enhance cellular redox-stress, susceptibility to dopamine-induced cell death, and repression of ubiquitin-dependent mitophagy. TSPO amplifies the extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) signalling, forming positive feedback, which represses the transcription factor EB (TFEB) and the controlled production of lysosomes. Finally, genetic variances in the transcriptome confirm that TSPO is required to alter the autophagy–lysosomal pathway during neurotoxicity.

scholarly journals Prostaglandin PGE2 receptor EP4 regulates microglial phagocytosis and increases susceptibility to diet-induced obesity

2021 ◽  
Author(s):  
Anzela Niraula ◽  
Rachael D Fasnacht ◽  
Kelly M Ness ◽  
Jeremy M Frey ◽  
Mauricio D Dorfman ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Microglial Activation ◽  
Body Weight Gain ◽  
Microglial Phagocytosis ◽  
Diet Induced Obesity ◽  
Insulin Tolerance ◽  
Pge2 Receptor

Background: In rodents, susceptibility to diet-induced obesity requires microglial activation, but the molecular components of this pathway remain incompletely defined. Prostaglandin E2 (PGE2) levels increase in the mediobasal hypothalamus during high fat diet (HFD) feeding, and the PGE2 receptor EP4 regulates microglial activation state and phagocytic activity, suggesting a potential role for microglial EP4 signaling in obesity pathogenesis. Method: Metabolic phenotyping, as assessed by body weight, energy expenditure, glucose, and insulin tolerance, was performed in microglia-specific EP4 knockout (MG-EP4 KO) mice and littermate controls on HFD. Morphological and gene expression analysis of microglia, and a histological survey of microglia-neuron interactions in the arcuate nucleus was performed. Phagocytosis was assessed using in vivo and in vitro pharmacological techniques. Results: Microglial EP4 deletion markedly reduced weight gain and food intake in response to HFD feeding. In correspondence with this lean phenotype, insulin sensitivity was also improved in the HFD-fed MG-EP4 KO mice though glucose tolerance remained surprisingly unaffected. Mechanistically, EP4-deficient microglia showed an attenuated phagocytic state marked by reduced CD68 expression and fewer contacts with POMC neuron soma and processes. These cellular changes observed in the microglial EP4 knockout mice corresponded with an increased density of POMC neurites extending into the paraventricular nucleus. Conclusion: These findings reveal that microglial EP4 signaling promotes body weight gain and insulin resistance during HFD feeding. Furthermore, the data suggest that curbing microglial phagocytic function may preserve POMC cytoarchitecture and PVN input to limit overconsumption during diet-induced obesity.

Phytosomal Curcumin Elicits Anti-tumor Properties Through Suppression of Angiogenesis, Cell Proliferation and Induction of Oxidative Stress in Colorectal Cancer

2019 ◽  
Vol 24 (39) ◽  
pp. 4626-4638 ◽  
Author(s):  
Reyhaneh Moradi-Marjaneh ◽  
Seyed M. Hassanian ◽  
Farzad Rahmani ◽  
Seyed H. Aghaee-Bakhtiari ◽  
Amir Avan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Colorectal Cancer ◽  
Therapeutic Potential ◽  
Vegf Signaling ◽  
Anticancer Effects ◽  
Inhibition Of Angiogenesis ◽  
Underlying Mechanisms ◽  
Apoptotic Activity

Background: Colorectal cancer (CRC) is one of the most common causes of cancer-associated mortality in the world. Anti-tumor effect of curcumin has been shown in different cancers; however, the therapeutic potential of novel phytosomal curcumin, as well as the underlying molecular mechanism in CRC, has not yet been explored. Methods: The anti-proliferative, anti-migratory and apoptotic activity of phytosomal curcumin in CT26 cells was assessed by MTT assay, wound healing assay and Flow cytometry, respectively. Phytosomal curcumin was also tested for its in-vivo activity in a xenograft mouse model of CRC. In addition, oxidant/antioxidant activity was examined by DCFH-DA assay in vitro, measurement of malondialdehyde (MDA), Thiol and superoxidedismutase (SOD) and catalase (CAT) activity and also evaluation of expression levels of Nrf2 and GCLM by qRT-PCR in tumor tissues. In addition, the effect of phytosomal curcumin on angiogenesis was assessed by the measurement of VEGF-A and VEGFR-1 and VEGF signaling regulatory microRNAs (miRNAs) in tumor tissue. Results: Phytosomal curcumin exerts anti-proliferative, anti-migratory and apoptotic activity in-vitro. It also decreases tumor growth and augmented 5-fluorouracil (5-FU) anti-tumor effect in-vivo. In addition, our data showed that induction of oxidative stress and inhibition of angiogenesis through modulation of VEGF signaling regulatory miRNAs might be underlying mechanisms by which phytosomal curcumin exerted its antitumor effect. Conclusion: Our data confirmed this notion that phytosomal curcumin administrates anticancer effects and can be used as a complementary treatment in clinical settings.

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