scholarly journals Development of a Protocol for Virtual Screening of PPARγ Weak Partial Agonists and Their Metabolites: Case Study on Naturally-derived Oleanane Triterpenoids

2021 ◽  
Vol 25 (2) ◽  
pp. 117-132
Author(s):  
Merilin Al Sharif ◽  
◽  
Petko Alov ◽  
Vessela Vitcheva ◽  
Antonia Diukendjieva ◽  
...  
Keyword(s):  
Virtual Screening ◽  
Molecular Mechanisms ◽  
Partial Agonist ◽  
Mechanistic Explanation ◽  
Binding Mode ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Partial Agonists ◽  
Docking Protocol ◽  
Agonistic Activity

Triterpenoids are well known metabolic syndrome (MetS) modulators. One of the suggested molecular mechanisms of action involves peroxisome proliferator-activated receptor gamma (PPARγ) activation. In this study we aimed to: (i) develop a virtual screening (VS) protocol for PPARγ weak partial agonists, (ii) predict potential metabolic transformations of naturally-derived triterpenoids, and (iii) perform VS of the triterpenoids and their metabolites. The NIH PubMed system was searched for publications about naturally-derived oleanane triterpenoids which are agonists or up-regulators of PPARγ. Structure- and ligand-based methods were combined in the development of the VS protocol. Metabolites were predicted using Meteor Nexus expert system (Lhasa Limited). Two in-house virtual libraries of PPARγ weak partial agonists and naturally-derived triterpenoids with their predicted metabolites were compiled. The pharmacophore-based docking protocol was applied for VS of the collected triterpenoids. Most of the docking poses reproduced the binding mode of caulophyllogenin (a weak partial agonist) in a complex with PPARγ (PDB ID 5F9B). Our results contribute to the mechanistic explanation of the effects of triterpenoids suggesting possible weak partial agonistic activity toward PPARγ. This research can direct further studies on triterpenoids’ role in MetS modulation. The developed protocol can be applied for VS of any PPARγ weak partial agonists.

scholarly journals Cyclin-Dependent Kinase 5 Inhibitor Butyrolactone I Elicits a Partial Agonist Activity of Peroxisome Proliferator-Activated Receptor γ

Biomolecules ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 275 ◽  
Author(s):  
Sungjin Ahn ◽  
Dong Man Jang ◽  
Sung Chul Park ◽  
Seungchan An ◽  
Jongheon Shin ◽  
...  
Keyword(s):  
Target Identification ◽  
Partial Agonist ◽  
Binding Mode ◽  
Marine Fungus ◽  
Peroxisome Proliferator ◽  
Amino Acid Residues ◽  
Cyclin Dependent Kinase ◽  
Peroxisome Proliferator Activated Receptor ◽  
Hydrophobic Binding ◽  
Insulin Sensitizing Activity

Adiponectin is an adipocyte-derived cytokine having an insulin-sensitizing activity. During the phenotypic screening of secondary metabolites derived from the marine fungus Aspergillus terreus, a poly cyclin-dependent kinase (CDK) inhibitor butyrolactone I affecting CDK1 and CDK5 was discovered as a potent adiponectin production-enhancing compound in the adipogenesis model of human bone marrow-derived mesenchymal stem cells (hBM-MSCs). CDK5 inhibitors exhibit insulin-sensitizing activities by suppressing the phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ). However, the adiponectin production-enhancing activities of butyrolactone I have not been correlated with the potency of CDK5 inhibitor activities. In a target identification study, butyrolactone I was found to directly bind to PPARγ. In the crystal structure of the human PPARγ, the ligand-binding domain (LBD) in complex with butyrolactone I interacted with the amino acid residues located in the hydrophobic binding pockets of the PPARγ LBD, which is a typical binding mode of the PPARγ partial agonists. Therefore, the adiponectin production-enhancing effect of butyrolactone I was mediated by its polypharmacological dual modulator activities as both a CDK5 inhibitor and a PPARγ partial agonist.

scholarly journals Discovery of a Bradykinin B2 Partial Agonist Profile of Raloxifene in a Drug Repurposing Campaign

2020 ◽  
Vol 22 (1) ◽  
pp. 257
Author(s):  
Patricia Gomez-Gutierrez ◽  
Juan J. Perez
Keyword(s):  
Virtual Screening ◽  
Molecular Mechanisms ◽  
Partial Agonist ◽  
Drug Repurposing ◽  
Cytokine Storm ◽  
Bradykinin Receptors ◽  
Screening Process ◽  
Bradykinin Antagonists ◽  
Illness Progression

Covid-19 urges a deeper understanding of the underlying molecular mechanisms involved in illness progression to provide a prompt therapeutical response with an adequate use of available drugs, including drug repurposing. Recently, it was suggested that a dysregulated bradykinin signaling can trigger the cytokine storm observed in patients with severe Covid-19. In the scope of a drug repurposing campaign undertaken to identify bradykinin antagonists, raloxifene was identified as prospective compound in a virtual screening process. The pharmacodynamics profile of raloxifene towards bradykinin receptors is reported in the present work, showing a weak selective partial agonist profile at the B2 receptor. In view of this new profile, its possible use as a therapeutical agent for the treatment of severe Covid-19 is discussed.

scholarly journals RT-PCR analysis of corticotroph-associated genes expression in carcinoid tumours in the ectopic-ACTH syndrome

2006 ◽  
Vol 154 (1) ◽  
pp. 159-166 ◽  
Author(s):  
M Messager ◽  
C Carrière ◽  
X Bertagna ◽  
Y de Keyzer
Keyword(s):  
Transcription Factor ◽  
Molecular Mechanisms ◽  
Ectopic Acth Syndrome ◽  
Pcr Analysis ◽  
Peroxisome Proliferator ◽  
Rt Pcr ◽  
Ectopic Acth ◽  
Peroxisome Proliferator Activated Receptor ◽  
Carcinoid Tumours ◽  
Transcription Factor Genes

Objective: ACTH is frequently produced in non-pituitary tumours, leading to the ectopic-ACTH syndrome, but the molecular mechanisms of its expression remain obscure. This study was aimed at understanding the transcription mechanisms of the ACTH-precursor gene in carcinoid tumours of the lung or thymus. Design: Transcripts coding for a series of corticotroph-associated transcription factor genes were detected, together with markers of the corticotroph phenotype. We studied a series of 41 carcinoid tumours including 15 with proven ectopic-ACTH syndrome. Methods: Specific RT-PCR reactions were designed for each gene including alternatively spliced isoforms. Results: The markers of the corticotroph phenotype were detected in all ACTH-positive tumours. Expression of the Tpit and Pitx1 genes were not restricted to ACTH-positive tumours but were also detected in many ACTH-negative carcinoids. Only a subset of ACTH-negative tumours expressed NAK-1/Nur77, and NeuroD1 expression was detected in <50% of the tumours regardless of their secretory status. The glucocorticoid receptor alpha was detected in every tumour in contrast to its beta isoform detectable in a few tumours only. Chicken ovalbumin upstream promoter-transcription factor 1 (COUP-TF1) and peroxisome proliferator-activated receptor (PPAR) γ2 were expressed in 50% of the tumours of each group whereas PPARγ1 was expressed in almost every tumour. Conclusions: ACTH-positive carcinoids do not share a characteristic expression pattern of the corticotroph-associated transcription factor genes, suggesting that the transcriptional mechanisms of the ACTH-precursor gene differ from those in normal pituitary corticotrophs. Expression of Tpit and Pitx1 genes in most carcinoids suggests that some aspects of the pituitary corticotroph phenotype may belong to general carcinoid differentiation.

scholarly journals Growth hormone controls lipolysis by regulation of FSP27 expression

2018 ◽  
Vol 239 (3) ◽  
pp. 289-301 ◽  
Author(s):  
Rita Sharma ◽  
Quyen Luong ◽  
Vishva M Sharma ◽  
Mitchell Harberson ◽  
Brian Harper ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Growth Hormone ◽  
Intracellular Signaling ◽  
Molecular Mechanisms ◽  
Specific Protein ◽  
Negative Regulator ◽  
Gamma Activity ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor

Growth hormone (GH) has long been known to stimulate lipolysis and insulin resistance; however, the molecular mechanisms underlying these effects are unknown. In the present study, we demonstrate that GH acutely induces lipolysis in cultured adipocytes. This effect is secondary to the reduced expression of a negative regulator of lipolysis, fat-specific protein 27 (FSP27; aka Cidec) at both the mRNA and protein levels. These effects are mimicked in vivo as transgenic overexpression of GH leads to a reduction of FSP27 expression. Mechanistically, we show GH modulation of FSP27 expression is mediated through activation of both MEK/ERK- and STAT5-dependent intracellular signaling. These two molecular pathways interact to differentially manipulate peroxisome proliferator-activated receptor gamma activity (PPARγ) on the FSP27 promoter. Furthermore, overexpression of FSP27 is sufficient to fully suppress GH-induced lipolysis and insulin resistance in cultured adipocytes. Taken together, these data decipher a molecular mechanism by which GH acutely regulates lipolysis and insulin resistance in adipocytes.

LncRNA LOC102176306 plays important roles in goat testicular development

Reproduction ◽  
2021 ◽  
Vol 161 (5) ◽  
pp. 523-537
Author(s):  
Shi-Yu An ◽  
Zi-Fei Liu ◽  
El-Samahy M A ◽  
Ming-Tian Deng ◽  
Xiao-Xiao Gao ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Proliferation ◽  
Molecular Mechanisms ◽  
Complex Iii ◽  
Testicular Development ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Atp Production ◽  
Positive Effects ◽  
And Oxidative Stress

Long ncRNAs regulate a complex array of fundamental biological processes, while its molecular regulatory mechanism in Leydig cells (LCs) remains unclear. In the present study, we established the lncRNA LOC102176306/miR-1197-3p/peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) regulatory network by bioinformatic prediction, and investigated its roles in goat LCs. We found that lncRNA LOC102176306 could efficiently bind to miR-1197-3p and regulate PPARGC1A expression in goat LCs. Downregulation of lncRNA LOC102176306 significantly supressed testosterone (T) synthesis and ATP production, decreased the activities of antioxidant enzymes and mitochondrial complex I and complex III, caused the loss of mitochondrial membrane potential, and inhibited the proliferation of goat LCs by decreasing PPARGC1A expression, while these effects could be restored by miR-1197-3p inhibitor treatment. In addition, miR-1197-3p mimics treatment significantly alleviated the positive effects of lncRNA LOC102176306 overexpression on T and ATP production, antioxidant capacity and proliferation of goat LCs. Taken together, lncRNA LOC102176306 functioned as a sponge for miR-1197-3p to maintain PPARGC1A expression, thereby affecting the steroidogenesis, cell proliferation and oxidative stress of goat LCs. These findings extend our understanding of the molecular mechanisms of T synthesis, cell proliferation and oxidative stress of LCs.

Methanol Extract of Mongolian Iris bungei Maxim. Stimulates 3T3-L1 Adipocyte Differentiation

2021 ◽  
Vol 21 (7) ◽  
pp. 3943-3949
Author(s):  
Jaegoo Yeon ◽  
Sung-Suk Suh ◽  
Ui-Joung Youn ◽  
Badamtsetseg Bazarragchaa ◽  
Ganbold Enebish ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Fatty Acid Synthase ◽  
Molecular Mechanisms ◽  
Adipocyte Differentiation ◽  
Methanol Extract ◽  
Regulatory Element ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Peroxisome Proliferator Activated Receptor

Iris bungei Maxim. (IB), which is native to China and Mongolia, is used as a traditional medicine for conditions such as inflammation, cancer, and bacterial infections. However, the effects of Iris bungei Maxim. on adipocyte differentiation have not been studied. In the present study, we first demonstrated the molecular mechanisms underlying the adipogenic activity of the methanol extract of Mongolian I. bungei Maxim. (IB). IB significantly enhanced intracellular lipid accumulation and adipocyte differentiation in 3T3-L1 preadipocytes in a concentration-dependent manner. Moreover, IB markedly stimulated the expression of genes related to adipogenesis such as peroxisome proliferator-activated receptor γ, adiponectin, and aP2. In addition, we also observed that IB induces lipogenic genes such as fatty acid synthase, sterol regulatory element binding protein 1c, stearoyl-CoA desaturase, and acetyl-CoA carboxylase. Interestingly IB regulated adipocyte differentiation in both the early and middle stages. Taken together, these adipogenic and lipogenic effects of IB suggest its efficacy for the prevention and/or treatment of type 2 diabetes.

scholarly journals Sijunzi, Lizhong, and Fuzilizhong Decoction Alleviate Nonalcoholic Fatty Liver Disease through Activation of PPAR Pathway

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Jiayao Yang ◽  
Dongqing Tao ◽  
Wei Ma ◽  
Song Liu ◽  
Yan Liao ◽  
...  
Keyword(s):  
Liver Disease ◽  
Fatty Liver ◽  
High Fat Diet ◽  
Fatty Liver Disease ◽  
Molecular Mechanisms ◽  
Peroxisome Proliferator ◽  
High Fat ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nonalcoholic Fatty Liver ◽  
Chinese Herbal

Objective. Sijunzi, Lizhong, and Fuzilizhong decoction were traditional Chinese classic formulations, which are widely used in clinical treatment, and the underlying mechanism is unclear. In this study, we aim to investigate the molecular mechanisms underlying the protective effects of Sijunzi, Lizhong, and Fuzilizhong on nonalcoholic fatty liver disease (NAFLD). Methods. Male Wistar rats were fed a high-fat diet for four weeks to induce NAFLD and were thereafter administered Sijunzi (8 g/kg/d), Lizhong (10 g/kg/d), or Fuzilizhong (10 g/kg/d) by gavage for four weeks. Hepatic damage, lipid accumulation, inflammation, autophagy, and peroxisome proliferator-activated receptor-α signaling were evaluated. Results. The high-fat diet-fed rats showed typical symptoms of NAFLD, including elevated levels of hepatic damage indicators, increased hepatic lipid deposition and fibrosis, severe liver inflammation, and prominent autophagy. Upon administration of Sijunzi, Lizhong, and Fuzilizhong, liver health was improved remarkably, along with ameliorated symptoms of NAFLD. In addition, NAFLD-suppressed peroxisome proliferator-activated receptor-α signaling was reactivated after treatment with the three types of decoctions. Conclusions. The results collectively signify the effective therapeutic and protective functions of Sijunzi, Lizhong, and Fuzilizhong against NAFLD and demonstrate the potential of Chinese herbal medication in mitigating the symptoms of liver diseases. Novelty of the Work. Traditional Chinese herbal medicine has been used for centuries to treat various diseases, but the molecular mechanisms of individual ingredients have rarely been studied. The novelty of our work lies in elucidating the specific signaling pathways involved in the control of NAFLD using three common Chinese herbal decoctions. We suggest that natural herbal formulations can be effective therapeutic agents to combat against NAFLD.

scholarly journals Association with Coregulators Is the Major Determinant Governing Peroxisome Proliferator-activated Receptor Mobility in Living Cells

2006 ◽  
Vol 282 (7) ◽  
pp. 4417-4426 ◽  
Author(s):  
Cicerone Tudor ◽  
Jérôme N. Feige ◽  
Harikishore Pingali ◽  
Vidya Bhushan Lohray ◽  
Walter Wahli ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Molecular Mechanisms ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Living Cells ◽  
Correlation Spectroscopy ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Peroxisome Proliferator Activated Receptors

The nucleus is an extremely dynamic compartment, and protein mobility represents a key factor in transcriptional regulation. We showed in a previous study that the diffusion of peroxisome proliferator-activated receptors (PPARs), a family of nuclear receptors regulating major cellular and metabolic functions, is modulated by ligand binding. In this study, we combine fluorescence correlation spectroscopy, dual color fluorescence cross-correlation microscopy, and fluorescence resonance energy transfer to dissect the molecular mechanisms controlling PPAR mobility and transcriptional activity in living cells. First, we bring new evidence that in vivo a high percentage of PPARs and retinoid X receptors is associated even in the absence of ligand. Second, we demonstrate that coregulator recruitment (and not DNA binding) plays a crucial role in receptor mobility, suggesting that transcriptional complexes are formed prior to promoter binding. In addition, association with coactivators in the absence of a ligand in living cells, both through the N-terminal AB domain and the AF-2 function of the ligand binding domain, provides a molecular basis to explain PPAR constitutive activity.

Sign in / Sign up

Export Citation Format

Share Document