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1.
J Dairy Sci ; 107(2): 649-668, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37709024

RESUMEN

In dairy science, camel milk (CM) constitutes a center of interest for scientists due to its known beneficial effect on diabetes as demonstrated in many in vitro, in vivo, and clinical studies and trials. Overall, CM had positive effects on various parameters related to glucose transport and metabolism as well as the structural and functional properties of the pancreatic ß-cells and insulin secretion. Thus, CM consumption may help manage diabetes; however, such a recommendation will become rationale and clinically conceivable only if the exact molecular mechanisms and pathways involved at the cellular levels are well understood. Moreover, the application of CM as an alternative antidiabetic tool may first require the identification of the exact bioactive molecules behind such antidiabetic properties. In this review, we describe the advances in our knowledge of the molecular mechanisms reported to be involved in the beneficial effects of CM in managing diabetes using different in vitro and in vivo models. This mainly includes the effects of CM on the different molecular pathways controlling (1) insulin receptor signaling and glucose uptake, (2) the pancreatic ß-cell structure and function, and (3) the activity of key metabolic enzymes in glucose metabolism. Moreover, we described the current status of the identification of CM-derived bioactive peptides and their structure-activity relationship study and characterization in the context of molecular markers related to diabetes. Such an overview will not only enrich our scientific knowledge of the plausible mode of action of CM in diabetes but should ultimately rationalize the claim of the potential application of CM against diabetes. This will pave the way toward new directions and ideas for developing a new generation of antidiabetic products taking benefits from the chemical composition of CM.


Asunto(s)
Diabetes Mellitus , Leche , Animales , Leche/química , Camelus/metabolismo , Glucemia/análisis , Diabetes Mellitus/veterinaria , Hipoglucemiantes/farmacología , Péptidos/farmacología
2.
J Dairy Sci ; 105(3): 1848-1861, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34955280

RESUMEN

Lactoferrin (LF) is a milk protein that may be an interesting candidate for the antidiabetic properties of milk due to its well-documented bioactivity and implication in diabetes. Here, we investigated the functional action of LF purified from camel and bovine milk (cLF, bLF) on insulin receptors (IR) and their pharmacology and signaling in hepatocarcinoma (HepG2) and human embryonic kidney (HEK293) cells. For this, we examined IR activation by bioluminescence resonance energy transfer (BRET) technology and the phosphorylation of its key downstream signaling kinases by western blot. The purified cLF and bLF induced phosphorylation of IR, AKT, and ERK1/2 in HepG2 and HEK293 cells. The BRET assays in HEK293 cells confirm the pharmacological action of cLF and bLF on IR, with a possible allosteric mode of action. This reveals for the first time the bioactivity of LF toward IR function, indicating it as a potential bioactive protein behind the antidiabetic properties of camel milk.


Asunto(s)
Camelus , Lactoferrina , Receptor de Insulina , Animales , Camelus/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Lactoferrina/metabolismo , Sistema de Señalización de MAP Quinasas , Leche , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Insulina/metabolismo
3.
Nutr Health ; : 2601060221122213, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36065597

RESUMEN

Background: Whey proteins and their peptide derivatives have attracted a great attention of researchers in the pharmaceutical and nutritional fields, due to their numerous bio-functionalities. Aim: In the present research study, enzymatic protein hydrolysates (CWPHs) from camel whey proteins (CWPs) were produced and investigated for their antioxidant and antimicrobial potentials. Methods: Herein, Pepsin (gastric), and Trypsin and Chymotrypsin (pancreatic) enzymes were used to produce CWPHs. The obtained hydrolysates were characterize to ascertain the level of protein degradation and studies on their antimicrobial and antioxidant potential were conducted. Results: Among all CWPHs, a complete degradation of all different protein bands was perceived with Chymotrypsin-derived CWPHs, whereas, light bands of serum albumin and α-lactalbumin were observed with Trypsin and Pepsin-derived CWPHs. After enzymatic degradation, both CWPHs antioxidant and antimicrobial activities were improved. Chymotrypsin-derived CWPHs demonstrated higher DPPH and ABTS radical scavenging activities, anent the increase in proteolysis time. Compared to unhydrolyzed CWPs, higher metal chelating activities were displayed by Trypsin-derived CWPHs. No significant increase in the FRAP activities was noticed after CWPs hydrolysis using Trypsin and Chymotrypsin, while Pepsin-derived CWPHs showed higher reducing power. In terms of antimicrobial activity, significantly higher bacterial growth inhibition rates were exhibited by CWPHs compared to the unhydrolyzed CWP. Conclusion: Overall, CWPHs displayed enhanced antioxidative and antimicrobial properties.

4.
Int J Mol Sci ; 23(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35743124

RESUMEN

Over one billion people globally are vitamin D (VD) deficient. Studies on the biological roles of VD are numerous but very little on the stomach. This project aims to understand how gastric homeostasis is affected by VD deficiency caused by prolonged exposure to darkness alone or combined with VD deficient diet. Three groups of C57/BL6 mice were subjected to different light exposure conditions and diets for 12 months (n = 8−12/group): control­12 h/12 h light/dark SDL (Standard Diet/Light), 24 h dark SDD (Standard Diet/Dark), and 24 h dark VDD (VD deficient diet/Dark). Stomach samples were collected for different multi-label lectin-/immuno-histochemical and qRT-PCR analyses, and the serum for LC-MS-MS. We found that the membrane VD receptor is expressed widely in the stomach when compared to nuclear VD receptors. Compared to SDL, VDD mice developed mucous cell expansion with increased mucins-mRNA (3.27 ± 2.73 (p < 0.05)) increased apoptotic cells, 15 ± 7 (p ≤ 0.001)); decreased cell proliferation, 4 ± 4 (p < 0.05)) and decreased acid secretion 33 ± 2 µEq/kg (p ≤ 0.0001)). Interestingly, mice exposed to full darkness developed mild VD deficiency with higher VD epimer levels: 11.9 ± 2.08 ng/mL (p ≤ 0.0001)), expansion in zymogenic cell number (16 ± 3 (p ≤ 0.01)), and a reduction in acid secretion (18 ± 2 µEq/kg (p ≤ 0.0001)). In conclusion, changes in light exposure or VD levels have serious physiological effects on the gastric mucosa, which should be considered during the management of gastric disorders.


Asunto(s)
Deficiencia de Vitamina D , Animales , Proliferación Celular , Células Epiteliales/metabolismo , Homeostasis , Humanos , Ratones , Estómago , Vitamina D/metabolismo , Deficiencia de Vitamina D/metabolismo
5.
Int J Mol Sci ; 23(17)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36077163

RESUMEN

Developing a therapeutic antibody is a long, tedious, and expensive process. Many obstacles need to be overcome, such as biophysical properties (issues of solubility, stability, weak production yields, etc.), as well as cross-reactivity and subsequent toxicity, which are major issues. No in silico method exists today to solve such issues. We hypothesized that if we were able to properly measure the similarity between the CDRs of antibodies (Ab) by considering not only their evolutionary proximity (sequence identity) but also their structural features, we would be able to identify families of Ab recognizing similar epitopes. As a consequence, Ab within the family would share the property to recognize their targets, which would allow (i) to identify off-targets and forecast the cross-reactions, and (ii) to identify new Ab specific for a given target. Testing our method on 238D2, an antagonistic anti-CXCR4 nanobody, we were able to find new nanobodies against CXCR4 and to identify influenza hemagglutinin as an off-target of 238D2.


Asunto(s)
Gripe Humana , Anticuerpos de Dominio Único , Anticuerpos , Epítopos , Hemaglutininas , Humanos
6.
Molecules ; 27(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35408664

RESUMEN

Combinatory flooding techniques evolved over the years to mitigate various limitations associated with unitary flooding techniques and to enhance their performance as well. This study investigates the potential of a combination of 1-hexadecyl-3-methyl imidazolium bromide (C16mimBr) and monoethanolamine (ETA) as an alkali-surfactant (AS) formulation for enhanced oil recovery. The study is conducted comparative to a conventional combination of cetyltrimethylammonium bromide (CTAB) and sodium metaborate (NaBO2). The study confirmed that C16mimBr and CTAB have similar aggregation behaviors and surface activities. The ETA-C16mimBr system proved to be compatible with brine containing an appreciable concentration of divalent cations. Studies on interfacial properties showed that the ETA-C16mimBr system exhibited an improved IFT reduction capability better than the NaBO2-CTAB system, attaining an ultra-low IFT of 7.6 × 10-3 mN/m. The IFT reduction performance of the ETA-C16mimBr system was improved in the presence of salt, attaining an ultra-low IFT of 2.3 × 10-3 mN/m. The system also maintained an ultra-low IFT even in high salinity conditions of 15 wt% NaCl concentration. Synergism was evident for the ETA-C16mimBr system also in altering the carbonate rock surface, while the wetting power of CTAB was not improved by the addition of NaBO2. Both the ETA-C16mimBr and NaBO2-CTAB systems proved to form stable emulsions even at elevated temperatures. This study, therefore, reveals that a combination of surface-active ionic liquid and organic alkali has excellent potential in enhancing the oil recovery in carbonate reservoirs at high salinity, high-temperature conditions in carbonate formations.


Asunto(s)
Líquidos Iónicos , Álcalis , Carbonatos , Cetrimonio , Tensión Superficial , Humectabilidad
7.
Arch Toxicol ; 95(5): 1671-1681, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33638691

RESUMEN

Dichlorodiphenyltrichloroethane (p,p'DDT) is an endocrine-disrupting chemical (EDC). Several studies showed an association between p,p'DDT exposure and reprotoxic effects. We showed that p,p'DDT was a positive allosteric modulator of human follitropin receptor (FSHR). In contrast, we demonstrated that p,p'DDT decreased the cyclic AMP (cAMP) production induced by human choriogonadotropin (hCG). This study evaluated further the effects of p,p'DDT on Gs-, ß-arrestin 2- and steroidogenesis pathways induced by hCG or luteinizing hormone (LH). We used Chinese hamster ovary cells line stably expressing hCG/LHR. The effects of 10-100 µM p,p'DDT on cAMP production and on ß-arrestin 2 recruitment were measured using bioluminescence and time-resolved resonance energy transfer technology. The impact of 100 µM of p,p'DDT on steroid secretion was analysed in murine Leydig tumor cell line (mLTC-1). In cAMP assays, 100 µM p,p'DDT increased the EC50 by more than 300% and reduced the maximum response of the hCG/LHR to hCG and hLH by 30%. This inhibitory effect was also found in human granulosa cells line and in mLTC-1 cells. Likewise, 100 µM p,p'DDT decreased the hCG- and hLH-promoted ß-arrestin 2 recruitment down to 14.2 and 26.6%, respectively. Moreover, 100 µM p,p'DDT decreased by 30 and 47% the progesterone secretion induced by hCG or hLH, respectively, without affecting testosterone secretion. This negative effect of p,p'DDT was independent of cytotoxicity. p,p'DDT acted as a negative allosteric modulator of the hCG/LHR signalling. This emphasizes the importance of analyzing all receptor-downstream pathways to fully understand the deleterious effects of EDC on human health.


Asunto(s)
DDT/toxicidad , Disruptores Endocrinos/toxicidad , Animales , Células CHO , Gonadotropina Coriónica , Cricetinae , Cricetulus , AMP Cíclico , Femenino , Humanos , Células Intersticiales del Testículo , Hormona Luteinizante/metabolismo , Masculino , Ratones , Receptores Acoplados a Proteínas G , Receptores de HL , Transducción de Señal
8.
J Dairy Sci ; 104(1): 61-77, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33162074

RESUMEN

The molecular basis of the anti-diabetic properties of camel milk reported in many studies and the exact active agent are still elusive. Recent studies have reported effects of camel whey proteins (CWP) and their hydrolysates (CWPH) on the activities of dipeptidyl peptidase IV (DPP-IV) and the human insulin receptor (hIR). In this study, CWPH were generated, screened for DPP-IV binding in silico and inhibitory activity in vitro, and processed for peptide identification. Furthermore, pharmacological action of intact CWP and their selected hydrolysates on hIR activity and signaling and on glucose uptake were investigated in cell lines. Results showed inhibition of DPP-IV by CWP and CWPH and their positive action on hIR activation and glucose uptake. Interestingly, the combination of CWP or CWPH with insulin revealed a positive allosteric modulation of hIR that was drastically reduced by the competitive hIR antagonist. Our data reveal for the first time the profiling and pharmacological actions of CWP and their derived peptides fractions on hIR and their pathways involved in glucose homeostasis. This sheds more light on the anti-diabetic properties of camel milk by providing the molecular basis for the potential use of camel milk in the management of diabetes.


Asunto(s)
Camelus , Dipeptidil Peptidasa 4/metabolismo , Hipoglucemiantes/farmacología , Leche/fisiología , Receptor de Insulina/metabolismo , Animales , Camelus/metabolismo , Simulación por Computador , Diabetes Mellitus/veterinaria , Dipeptidil Peptidasa 4/química , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Humanos , Hipoglucemiantes/metabolismo , Leche/química , Proteínas de la Leche/química , Proteínas de la Leche/farmacología , Péptidos/metabolismo , Fosforilación , Proteína de Suero de Leche/metabolismo
9.
Int J Mol Sci ; 22(18)2021 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-34576014

RESUMEN

Follicle-stimulating hormone receptor (FSHR) plays a key role in reproduction through the activation of multiple signaling pathways. Low molecular weight (LMW) ligands composed of biased agonist properties are highly valuable tools to decipher complex signaling mechanisms as they allow selective activation of discrete signaling cascades. However, available LMW FSHR ligands have not been fully characterized yet. In this context, we explored the pharmacological diversity of three benzamide and two thiazolidinone derivatives compared to FSH. Concentration/activity curves were generated for Gαs, Gαq, Gαi, ß-arrestin 2 recruitment, and cAMP production, using BRET assays in living cells. ERK phosphorylation was analyzed by Western blotting, and CRE-dependent transcription was assessed using a luciferase reporter assay. All assays were done in either wild-type, Gαs or ß-arrestin 1/2 CRISPR knockout HEK293 cells. Bias factors were calculated for each pair of read-outs by using the operational model. Our results show that each ligand presented a discrete pharmacological efficacy compared to FSH, ranging from super-agonist for ß-arrestin 2 recruitment to pure Gαs bias. Interestingly, LMW ligands generated kinetic profiles distinct from FSH (i.e., faster, slower or transient, depending on the ligand) and correlated with CRE-dependent transcription. In addition, clear system biases were observed in cells depleted of either Gαs or ß-arrestin genes. Such LMW properties are useful pharmacological tools to better dissect the multiple signaling pathways activated by FSHR and assess their relative contributions at the cellular and physio-pathological levels.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP/farmacología , Receptores de HFE/agonistas , Arrestina beta 2/farmacología , AMP Cíclico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células HEK293 , Humanos , Cinética
10.
Traffic ; 19(1): 58-82, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29044966

RESUMEN

The signaling pathway of G protein-coupled receptors is strongly linked to their trafficking profile. Little is known about the molecular mechanisms involved in the vasopressin receptor V1b subtype (V1b R) trafficking and its impact on receptor signaling and regulation. For this purpose, we investigated the role of ß-arrestins in receptor desensitization, internalization and recycling and attempted to dissect the V1b R-mediated MAP kinase pathway. Using MEF cells Knocked-out for ß-arrestins 1 and 2, we demonstrated that both ß-arrestins 1 and 2 play a fundamental role in internalization and recycling of V1b R with a rapid and transient V1b R-ß-arrestin interaction in contrast to a slow and long-lasting ß-arrestin recruitment of the V2 vasopressin receptor subtype (V2 R). Using V1b R-V2 R chimeras and V1b R C-terminus truncations, we demonstrated the critical role of the V1b R C-terminus in its interaction with ß-arrestins thereby regulating the receptor internalization and recycling kinetics in a phosphorylation-independent manner. In parallel, V1b R MAP kinase activation was dependent on arrestins and Src-kinase but independent on G proteins. Interestingly, Src interacted with hV1b R at basal state and dissociated when receptor internalization occurred. Altogether, our data describe for the first time the trafficking profile and MAP kinase pathway of V1b R involving both arrestins and Src kinase family.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Receptores de Vasopresinas/metabolismo , beta-Arrestinas/metabolismo , Animales , Sitios de Unión , Proteínas de Unión al GTP/metabolismo , Células HEK293 , Humanos , Ratones , Unión Proteica , Transporte de Proteínas , beta-Arrestinas/química , Familia-src Quinasas/metabolismo
11.
J Immunol ; 201(10): 3096-3105, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30322966

RESUMEN

Abs are very efficient drugs, ∼70 of them are already approved for medical use, over 500 are in clinical development, and many more are in preclinical development. One important step in the characterization and protection of a therapeutic Ab is the determination of its cognate epitope. The gold standard is the three-dimensional structure of the Ab/Ag complex by crystallography or nuclear magnetic resonance spectroscopy. However, it remains a tedious task, and its outcome is uncertain. We have developed MAbTope, a docking-based prediction method of the epitope associated with straightforward experimental validation procedures. We show that MAbTope predicts the correct epitope for each of 129 tested examples of Ab/Ag complexes of known structure. We further validated this method through the successful determination, and experimental validation (using human embryonic kidney cells 293), of the epitopes recognized by two therapeutic Abs targeting TNF-α: certolizumab and golimumab.


Asunto(s)
Anticuerpos Monoclonales/química , Mapeo Epitopo/métodos , Simulación del Acoplamiento Molecular/métodos , Células HEK293 , Humanos
12.
J Pediatr Gastroenterol Nutr ; 71(3): e90-e96, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32520831

RESUMEN

OBJECTIVES: Wilson disease (WD) presenting as acute liver failure (ALF) is rare and typically fatal without liver transplantation (LT). Its rarity has hindered comprehensive studies. We undertook an individual patient data meta-analysis to characterize a cohort of pediatric patients presenting with ALF whose final diagnosis was WD to examine outcomes and identify predictors of poor outcomes. METHODS: Database searches were conducted in PubMed, ScienceDirect, and Google Scholar, restricted to English-language articles published between January 1984 and May 2018. Articles were excluded if pediatric (<18 years old) data were not extractable or if LT was not readily available at reporting institutions. Extracted data included clinical and biochemical characteristics, genotype, treatment, and outcome. RESULTS: Data were available on 249 subjects from 52 articles, plus 7 additional subjects identified from our institution's WD database (N = 256). Females represented 69% (n = 170/245). Median age at presentation was 13.4 years (n = 204, range 4.0-17.9). Of the total 256 subjects, 87% underwent LT, 11% achieved spontaneous recovery and 2% died before LT. International normalized ratio >2.0 at presentation was a predictor of LT/death (odds ratio 7.6, 95% confidence interval 1.5-28), with a trend observed for hepatic encephalopathy (HE) (odds ratio 4.18, 95% confidence interval 0.99-18). Arithmetic diagnostic scores proved inferior in the pediatric age-bracket compared to adults. CONCLUSIONS: This large international pediatric cohort has permitted an individual patient data analysis of WD presenting as ALF. Notably, 11% of subjects achieved spontaneous survival; the rest required LT. Coagulopathy (international normalized ratio >2:0) and HE at presentation heralded poor outcomes. Further prospective studies may identify additional early predictors of outcomes.


Asunto(s)
Encefalopatía Hepática , Degeneración Hepatolenticular , Fallo Hepático Agudo , Trasplante de Hígado , Adolescente , Adulto , Niño , Femenino , Degeneración Hepatolenticular/complicaciones , Degeneración Hepatolenticular/diagnóstico , Humanos , Fallo Hepático Agudo/diagnóstico , Fallo Hepático Agudo/etiología , Estudios Prospectivos
13.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33379211

RESUMEN

Hemorphins are known for their role in the control of blood pressure. Recently, we revealed the positive modulation of the angiotensin II (AngII) type 1 receptor (AT1R) by LVV-hemorphin-7 (LVV-H7) in human embryonic kidney (HEK293) cells. Here, we examined the molecular binding behavior of LVV-H7 on AT1R and its effect on AngII binding using a nanoluciferase-based bioluminescence resonance energy transfer (NanoBRET) assay in HEK293FT cells, as well as molecular docking and molecular dynamics (MD) studies. Saturation and real-time kinetics supported the positive effect of LVV-H7 on the binding of AngII. While the competitive antagonist olmesartan competed with AngII binding, LVV-H7 slightly, but significantly, decreased AngII's kD by 2.6 fold with no effect on its Bmax. Molecular docking and MD simulations indicated that the binding of LVV-H7 in the intracellular region of AT1R allosterically potentiates AngII binding. LVV-H7 targets residues on intracellular loops 2 and 3 of AT1R, which are known binding sites of allosteric modulators in other GPCRs. Our data demonstrate the allosteric effect of LVV-H7 on AngII binding, which is consistent with the positive modulation of AT1R activity and signaling previously reported. This further supports the pharmacological targeting of AT1R by hemorphins, with implications in vascular and renal physiology.


Asunto(s)
Angiotensina II/metabolismo , Hemoglobinas/metabolismo , Fragmentos de Péptidos/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Células HEK293 , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular
14.
Annu Rev Pharmacol Toxicol ; 56: 403-25, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26514203

RESUMEN

G protein-coupled receptors (GPCRs) compose one of the largest families of membrane proteins involved in intracellular signaling. They are involved in numerous physiological and pathological processes and are prime candidates for drug development. Over the past decade, an increasing number of studies have reported heteromerization between GPCRs. Many investigations in heterologous systems have provided important indications of potential novel pharmacology; however, the physiological relevance of these findings has yet to be established with endogenous receptors in native tissues. In this review, we focus on family A GPCRs and describe the techniques and criteria to assess their heteromerization. We conclude that advances in approaches to study receptor complex functionality in heterologous systems, coupled with techniques that enable specific examination of native receptor heteromers in vivo, are likely to establish GPCR heteromers as novel therapeutic targets.


Asunto(s)
Receptores Acoplados a Proteínas G/metabolismo , Animales , Descubrimiento de Drogas/métodos , Humanos , Proteínas de la Membrana/metabolismo , Transducción de Señal/fisiología
15.
FASEB J ; 32(3): 1154-1169, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29084767

RESUMEN

Many interaction partners of ß-arrestins intervene in the control of mRNA translation. However, how ß-arrestins regulate this cellular process has been poorly explored. In this study, we show that ß-arrestins constitutively assemble a p70S6K/ribosomal protein S6 (rpS6) complex in HEK293 cells and in primary Sertoli cells of the testis. We demonstrate that this interaction is direct, and experimentally validate the interaction interface between ß-arrestin 1 and p70S6K predicted by our docking algorithm. Like most GPCRs, the biological function of follicle-stimulating hormone receptor (FSHR) is transduced by G proteins and ß-arrestins. Upon follicle-stimulating hormone (FSH) stimulation, activation of G protein-dependent signaling enhances p70S6K activity within the ß-arrestin/p70S6K/rpS6 preassembled complex, which is not recruited to the FSHR. In agreement, FSH-induced rpS6 phosphorylation within the ß-arrestin scaffold was decreased in cells depleted of Gαs. Integration of the cooperative action of ß-arrestin and G proteins led to the translation of 5' oligopyrimidine track mRNA with high efficacy within minutes of FSH input. Hence, this work highlights new relationships between G proteins and ß-arrestins when acting cooperatively on a common signaling pathway, contrasting with their previously shown parallel action on the ERK MAP kinase pathway. In addition, this study provides insights into how GPCR can exert trophic effects in the cell.-Tréfier, A., Musnier, A., Landomiel, F., Bourquard, T., Boulo, T., Ayoub, M. A., León, K., Bruneau, G., Chevalier, M., Durand, G., Blache, M.-C., Inoue, A., Fontaine, J., Gauthier, C., Tesseraud, S., Reiter, E., Poupon, A., Crépieux, P. G protein-dependent signaling triggers a ß-arrestin-scaffolded p70S6K/ rpS6 module that controls 5'TOP mRNA translation.


Asunto(s)
Regiones no Traducidas 5'/genética , Proteínas de Unión al GTP/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Proteína S6 Ribosómica/metabolismo , beta-Arrestinas/metabolismo , Animales , Masculino , Mapas de Interacción de Proteínas , Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , Ratas , Ratas Wistar , Receptores de HFE/metabolismo , Células de Sertoli/metabolismo , Transducción de Señal
16.
Mol Hum Reprod ; 23(10): 685-697, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29044421

RESUMEN

STUDY QUESTION: Are four urinary hCG/menotropin (hMG) and one recombinant preparation characterized by different molecular features and do they mediate specific intracellular signaling and steroidogenesis? SUMMARY ANSWER: hCG and hMG preparations have heterogeneous compositions and mediate preparation-specific cell signaling and early steroidogenesis, although similar progesterone plateau levels are achieved in 24 h-treated human primary granulosa cells in vitro. WHAT IS KNOWN ALREADY: hCG is the pregnancy hormone marketed as a drug for ARTs to induce final oocyte maturation and ovulation, and to support FSH action. Several hCG formulations are commercially available, differing in source, purification methods and biochemical composition. STUDY DESIGN, SIZE, DURATION: Commercial hCG preparations for ART or research purposes were compared in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS: The different preparations were quantified by immunoassay with calibration against the hCG standard (Fifth IS; NIBSC 07/364). Immunoreactivity patterns, isoelectric points and oligosaccharide contents of hCGs were evaluated using reducing and non-reducing Western blotting, capillary isoelectric-focusing immunoassay and lectin-ELISA, respectively. Functional studies were performed in order to evaluate intracellular and total cAMP, progesterone production and ß-arrestin 2 recruitment by ELISA and BRET, in both human primary granulosa lutein cells (hGLC) and luteinizing hormone (LH)/hCG receptor (LHCGR)-transfected HEK293 cells, stimulated by increasing hormone concentrations. Statistical analysis was performed using two-way ANOVA and Bonferroni post-test or Mann-Whitney's U-test as appropriate. MAIN RESULTS AND THE ROLE OF CHANCE: Heterogeneous profiles were found among preparations, revealing specific molecular weight patterns (20-75 KDa range), isoelectric points (4.0-9.0 pI range) and lectin binding (P < 0.05; n = 7-10). These drug-specific compositions were linked to different potencies on cAMP production (EC50 1.0-400.0 ng/ml range) and ß-arrestin 2 recruitment (EC50 0.03-2.0 µg/ml) in hGLC and transfected HEK293 cells (P < 0.05; n = 3-5). In hGLC, these differences were reflected by preparation-specific 8-h progesterone production although similar plateau levels of progesterone were acheived by 24-h treatment (P ≥ 0.05; n = 3). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The biological activity of commercial hCG/hMG preparations is provided in International Units (IU) by in-vivo bioassay and calibration against an International Standard, although it is an unsuitable unit of measure for in-vitro studies. The re-calibration against recombinant hCG,quantified in grams, is based on the assumption that all of the isoforms and glycosylation variants have similar immunoreactivity. WIDER IMPLICATIONS OF THE FINDINGS: hCG/hMG preparation-specific cell responses in vitro may be proposed to ART patients affected by peculiar ovarian response, such as that caused by polycystic ovary syndrome. Otherwise, all the preparations available for ART may provide a similar clinical outcome in healthy women. STUDY FUNDING AND COMPETING INTEREST(S): This study was supported by a grant of the Italian Ministry of Education, University and Research (PRIN 2015XCR88M). The authors have no conflict of interest.


Asunto(s)
Gonadotropina Coriónica/química , Fármacos para la Fertilidad Femenina/química , Células de la Granulosa/efectos de los fármacos , Menotropinas/química , Progesterona/biosíntesis , Transducción de Señal/efectos de los fármacos , Adulto , Gonadotropina Coriónica/farmacología , AMP Cíclico/biosíntesis , Femenino , Fármacos para la Fertilidad Femenina/farmacología , Hormona Folículo Estimulante/genética , Hormona Folículo Estimulante/metabolismo , Regulación de la Expresión Génica , Células de la Granulosa/citología , Células de la Granulosa/metabolismo , Células HEK293 , Humanos , Punto Isoeléctrico , Fase Luteínica/fisiología , Menotropinas/farmacología , Peso Molecular , Inducción de la Ovulación/métodos , Embarazo , Cultivo Primario de Células , Receptores de HL/genética , Receptores de HL/metabolismo , Transfección , Arrestina beta 2/genética , Arrestina beta 2/metabolismo
17.
FASEB J ; 30(12): 4180-4191, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27609774

RESUMEN

The Salmonella Rck outer membrane protein binds to the cell surface, which leads to bacterial internalization via a Zipper mechanism. This invasion process requires induction of cellular signals, including phosphorylation of tyrosine proteins, and activation of c-Src and PI3K, which arises as a result of an interaction with a host cell surface receptor. In this study, epidermal growth factor receptor (EGFR) was identified as the cell signaling receptor required for Rck-mediated adhesion and internalization. First, Rck-mediated adhesion and internalization were shown to be altered when EGFR expression and activity were modulated. Then, immunoprecipitations were performed to demonstrate the Rck-EGFR interaction. Furthermore, surface plasmon resonance biosensor and homogeneous time-resolved fluorescence technologies were used to demonstrate the direct interaction of Rck with the extracellular domain of human EGFR. Finally, our study strongly suggests a noncompetitive binding of Rck and EGF to EGFR. Overall, these results demonstrate that Rck is able to bind to EGFR and thereby establish a tight adherence to provide a signaling cascade, which leads to internalization of Rck-expressing bacteria.-Wiedemann, A., Mijouin, L., Ayoub, M. A., Barilleau, E., Canepa, S., Teixeira-Gomes, A. P., Le Vern, Y., Rosselin, M., Reiter, E., Velge, P. Identification of the epidermal growth factor receptor as the receptor for Salmonella Rck-dependent invasion.


Asunto(s)
Membrana Celular/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Salmonella/metabolismo , Proteína Tirosina Quinasa CSK , Línea Celular , Escherichia coli , Fosforilación , Receptores de Superficie Celular/metabolismo , Transducción de Señal/fisiología , Familia-src Quinasas/metabolismo
18.
Environ Pollut ; 362: 124995, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39306066

RESUMEN

This study presents a temporal evaluation of the tropospheric NO2 column densities over Greater Doha using TROPOMI satellite data from May 2018 to December 2023, and an assessment of the impact of the preparations and hosting of the FIFA Football World Cup Qatar 2022, on NO2 levels before, during and after the tournament over Greater Doha. Analysis of annual NO2 levels from 2019 to 2023 showed an increase in 2022 compared to that of the previous three years and a clear decrease in 2023 post the completion of the world cup preparations and hosting. Results also showed an increase in NO2 levels during winter compared to that in summer, with wind speed being an important determining factor. Findings showed that Fridays and Saturdays (both constitute the local weekend in Qatar) were 44% and 13% lower than that of the averaged weekdays, respectively. The annual NO2 levels in the post-world cup year of 2023 were found to be 24% lower than that in 2022 and around 16% lower than that of the previous years. NO2 levels during the World Cup tournament (20 Nov to Dec 18, 2022) were found to be higher than that of the same corresponding periods in all other available years including an increase of 27% compared to that in 2023. Wind speed played an important role in determining the NO2 levels during the world cup period and accounted for >96% of their daily variability, indicating that meteorological factors substantially influenced the NO2 column during the event.

19.
Clin Res Cardiol ; 113(4): 626-641, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37093246

RESUMEN

OBJECTIVE: The study investigates the prognostic impact of cardiogenic shock (CS) stratified by the presence or absence of acute myocardial infarction (AMI). BACKGROUND: Intensive care unit (ICU) related mortality in CS patients remains unacceptably high despite improvement concerning the treatment of CS patients. METHODS: Consecutive patients with CS from 2019 to 2021 were included monocentrically. The prognostic impact of CS related to AMI was compared to patients without AMI-related CS. The primary endpoint was 30-day all-cause mortality. Statistical analyses included Kaplan-Meier analyses, multivariable Cox proportional regression analyses and propensity score matching. RESULTS: 273 CS patients were included (AMI-related CS: 49%; non-AMI-related CS: 51%). The risk of 30-day all-cause mortality was increased in patients with AMI-related CS (64% vs. 47%; HR = 1.653; 95% CI 1.199-2.281; p = 0.002), which was still observed after multivariable adjustment (HR = 1.696; 95% CI 1.153-2.494; p = 0.007). Even after propensity score matching (i.e., 87 matched pairs), AMI was still an independent predictor of 30-day mortality (HR = 1.524; 95% CI 1.020-2.276; p = 0.040). In contrast, non-ST-segment AMI (NSTEMI) and STEMI were associated with comparable prognosis (log-rank p = 0.528). CONCLUSION: AMI-related CS was associated with increased 30-day all-cause mortality compared to patients with CS not related to AMI. In contrast, the prognosis of STEMI- and NSTEMI-CS patients was comparable.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Infarto del Miocardio con Elevación del ST , Humanos , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/etiología , Choque Cardiogénico/terapia , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/terapia , Infarto del Miocardio sin Elevación del ST/complicaciones , Infarto del Miocardio sin Elevación del ST/diagnóstico , Infarto del Miocardio sin Elevación del ST/terapia , Estudios Prospectivos , Factores de Riesgo , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico , Pronóstico , Sistema de Registros
20.
Biomed Pharmacother ; 170: 116070, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163396

RESUMEN

Two-dimensional (2D) nanomaterials have garnered enormous attention seemingly due to their unusual architecture and properties. Graphene and graphene oxide based 2D nanomaterials remained the most sought after for several years but the quest to design superior 2D nanomaterials which can find wider application gave rise to development of non-graphene 2D materials as well. Consequently, in addition to graphene based 2D nanomaterials, 2D nanostructures designed using macromolecules (such as DNAs, proteins, peptides and peptoids), transition metal dichalcogenides, transition-metal carbides and/or nitrides (MXene), black phosphorous, chitosan, hexagonal boron nitrides, and graphitic carbon nitride, and covalent organic frameworks have been developed. Interestingly, these 2D nanomaterials have found applications in diagnosis and treatment of various diseases including Alzheimer's disease (AD). Although AD is one of the most debilitating neurodegenerative conditions across the globe; unfortunately, there remains a paucity of effective diagnostic and/or therapeutic intervention for it till date. In this scenario, nanomaterial-based biosensors, or therapeutics especially 2D nanostructures are emerging to be promising in this regard. This review summarizes the diagnostic and therapeutic platforms developed for AD using 2D nanostructures. Collectively, it is worth mentioning that these 2D nanomaterials would seemingly provide an alternative and intriguing platform for biomedical interventions.


Asunto(s)
Enfermedad de Alzheimer , Técnicas Biosensibles , Grafito , Nanoestructuras , Humanos , Grafito/química , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Nanoestructuras/uso terapéutico , Nanoestructuras/química , Técnicas Biosensibles/métodos
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