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Management of chronic obesity-associated metabolic disorders is a key challenge for biomedical researchers. During chronic obesity, visceral adipose tissue (VAT) undergoes substantial transformation characterized by a unique lipid-rich hypoxic AT microenvironment which plays a crucial role in VAT dysfunction, leading to insulin resistance (IR) and type 2 diabetes. Here, we demonstrate that obese AT microenvironment triggers the release of miR-210-3p microRNA-loaded extracellular vesicles from adipose tissue macrophages, which disseminate miR-210-3p to neighboring adipocytes, skeletal muscle cells, and hepatocytes through paracrine and endocrine actions, thereby influencing insulin sensitivity. Moreover, EVs collected from Dicer-silenced miR-210-3p-overexpressed bone marrow-derived macrophages induce glucose intolerance and IR in lean mice. Mechanistically, miR-210-3p interacts with the 3'-UTR of GLUT4 mRNA and silences its expression, compromising cellular glucose uptake and insulin sensitivity. Therapeutic inhibition of miR-210-3p in VAT notably rescues high-fat diet-fed mice from obesity-induced systemic glucose intolerance. Thus, targeting adipose tissue macrophage-specific miR-210-3p during obesity could be a promising strategy for managing IR and type 2 diabetes.
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Transportador de Glucosa de Tipo 4 , Resistencia a la Insulina , Macrófagos , MicroARNs , Obesidad , MicroARNs/genética , MicroARNs/metabolismo , Animales , Obesidad/metabolismo , Obesidad/genética , Obesidad/patología , Macrófagos/metabolismo , Ratones , Transportador de Glucosa de Tipo 4/metabolismo , Transportador de Glucosa de Tipo 4/genética , Masculino , Ratones Endogámicos C57BL , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Humanos , Dieta Alta en Grasa/efectos adversos , Intolerancia a la Glucosa/metabolismo , Intolerancia a la Glucosa/genética , Intolerancia a la Glucosa/patología , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patologíaRESUMEN
An imbalance in microbial homeostasis, referred to as dysbiosis, is critically associated with the progression of obesity-induced metabolic disorders including type 2 diabetes (T2D). Alteration in gut microbial diversity and the abundance of pathogenic bacteria disrupt metabolic homeostasis and potentiate chronic inflammation, due to intestinal leakage or release of a diverse range of microbial metabolites. The obesity-associated shifts in gut microbial diversity worsen the triglyceride and cholesterol level that regulates adipogenesis, lipolysis, and fatty acid oxidation. Moreover, an intricate interaction of the gut-brain axis coupled with the altered microbiome profile and microbiome-derived metabolites disrupt bidirectional communication for instigating insulin resistance. Furthermore, a distinct microbial community within visceral adipose tissue is associated with its dysfunction in obese T2D individuals. The specific bacterial signature was found in the mesenteric adipose tissue of T2D patients. Recently, it has been shown that in Crohn's disease, the gut-derived bacterium Clostridium innocuum translocated to the mesenteric adipose tissue and modulates its function by inducing M2 macrophage polarization, increasing adipogenesis, and promoting microbial surveillance. Considering these facts, modulation of microbiota in the gut and adipose tissue could serve as one of the contemporary approaches to manage T2D by using prebiotics, probiotics, or faecal microbial transplantation. Altogether, this review consolidates the current knowledge on gut and adipose tissue dysbiosis and its role in the development and progression of obesity-induced T2D. It emphasizes the significance of the gut microbiota and its metabolites as well as the alteration of adipose tissue microbiome profile for promoting adipose tissue dysfunction, and identifying novel therapeutic strategies, providing valuable insights and directions for future research and potential clinical interventions.
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Visceral leishmaniasis (VL) is a severe form of leishmaniasis, primarily affecting the poor in developing countries. Although several studies have highlighted the importance of toll-like receptors (TLRs) in the pathophysiology of leishmaniasis, the role of specific TLRs and their binding partners involved in Leishmania donovani uptake are still elusive. To investigate the mechanism of L. donovani entry inside the macrophages, we found that the parasite lipophosphoglycan (LPG) interacted with the macrophage TLR4, leading to parasite uptake without any significant alteration of macrophage cell viability. Increased parasite numbers within macrophages markedly inhibited lipopolysachharide-induced pro-inflammatory cytokines gene expression. Silencing of macrophage-TLR4, or inhibition of parasite-LPG, significantly stemmed parasite infection in macrophages. Interestingly, we observed a significant enhancement of macrophage migration, and generation of reactive oxygen species (ROS) in the parasite-infected TLR4-silenced macrophages, whereas parasite infection in TLR4-overexpressed macrophages exhibited a notable reduction of macrophage migration and ROS generation. Moreover, mutations in the leucine-rich repeats (LRRs), particularly LRR5 and LRR6, significantly prevented TLR4 interaction with LPG, thus inhibiting cellular parasite entry. All these results suggest that parasite LPG recognition by the LRR5 and LRR6 of macrophage-TLR4 facilitated parasite entry, and impaired macrophage functions. Therefore, targeting LRR5/LRR6 interactions with LPG could provide a novel option to prevent VL.
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Leishmania donovani , Leishmaniasis Visceral , Parásitos , Animales , Receptor Toll-Like 4 , Especies Reactivas de Oxígeno , MacrófagosRESUMEN
The capability of bacteria to withstand the misuse of antibiotics leads to the generation of multi-drug resistant strains, posing a new challenge to curb wound infections. The biological macromolecules, due to their biocompatibility, biodegradability, and antimicrobial properties, have been explored for a variety of antimicrobial and therapeutic purposes. This work reports that a single-step oxidation of pullulan polymer leads to the formation of oxidized pullulan (o-pullulan), which shows striking antibacterial and antibiofilm activities against the Gram-positive bacteria, Staphylococcus aureus, implicated in wound-related infections. Oxidation of pullulan generates 28 % aldehyde groups (3.462 mmol/g) which exerted 97 % bactericidal activity against S. aureus by targeting cell wall-associated membrane protein SpA (Staphylococcal protein A). The molecular docking, gene silencing, and fluorescence quenching studies revealed a direct binding of o-pullulan with the B and C domains of SpA, which alters the membrane potential and inhibits Ca2+-Mg2+-ATPase pumps. O-pullulan also exhibited scavenging activity against intracellular reactive oxygen species (ROS), and non-immunotoxic activity and was found to be non-toxic to mammalian cells. Thus, o-pullulan shows great promise as an antimicrobial polymer against S. aureus for chronic wound management.
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Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Staphylococcus aureus , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Antiinfecciosos/farmacología , MamíferosRESUMEN
Increasing evidence supports vanillin and its analogs as potent toll-like receptor signaling inhibitors that strongly attenuate inflammation, though, the underlying molecular mechanism remains elusive. Here, we report that vanillin inhibits lipopolysaccharide (LPS)-induced toll-like receptor 4 activation in macrophages by targeting the myeloid differentiation primary-response gene 88 (MyD88)-dependent pathway through direct interaction and suppression of interleukin-1 receptor-associated kinase 4 (IRAK4) activity. Moreover, incubation of vanillin in cells expressing constitutively active forms of different toll-like receptor 4 signaling molecules revealed that vanillin could only able to block the ligand-independent constitutively activated IRAK4/1 or its upstream molecules-associated NF-κB activation and NF-κB transactivation along with the expression of various proinflammatory cytokines. A significant inhibition of LPS-induced IRAK4/MyD88, IRAK4/IRAK1, and IRAK1/TRAF6 association was evinced in response to vanillin treatment. Furthermore, mutations at Tyr262 and Asp329 residues in IRAK4 or modifications of 3-OMe and 4-OH side groups in vanillin, significantly reduced IRAK4 activity and vanillin function, respectively. Mice pretreated with vanillin followed by LPS challenge markedly impaired LPS-induced IRAK4 activation and inflammation in peritoneal macrophages. Thus, the present study posits vanillin as a novel and potent IRAK4 inhibitor and thus providing an opportunity for its therapeutic application in managing various inflammatory diseases.
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Lipopolisacáridos , FN-kappa B , Animales , Ratones , Inflamación/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Lipopolisacáridos/metabolismo , Macrófagos/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
Under the condition of chronic obesity, an increased level of free fatty acids along with low oxygen tension in the adipose tissue creates a pathophysiological adipose tissue microenvironment (ATenv), leading to the impairment of adipocyte function and insulin resistance. Here, we found the synergistic effect of hypoxia and lipid (H + L) surge in fostering adipose tissue macrophage (ATM) inflammation and polarization. ATenv significantly increased miR-210-3p expression in ATMs which promotes NF-κB activation-dependent proinflammatory cytokine expression along with the downregulation of anti-inflammatory cytokine expression. Interestingly, delivery of miR-210-3p mimic significantly increased macrophage inflammation in the absence of H + L co-stimulation, while miR-210-3p inhibitor notably compromised H + L-induced macrophage inflammation through increased production of suppressor of cytokine signaling 1 (SOCS1), a negative regulator of the NF-κB inflammatory signaling pathway. Mechanistically, miR-210 directly binds to the 3'-UTR of SOCS1 mRNA and silences its expression, thus preventing proteasomal degradation of NF-κB p65. Direct delivery of anti-miR-210-3p LNA in the ATenv markedly rescued mice from obesity-induced adipose tissue inflammation and insulin resistance. Thus, miR-210-3p inhibition in ATMs could serve as a novel therapeutic strategy for managing obesity-induced type 2 diabetes.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , MicroARNs , Ratones , Animales , FN-kappa B/metabolismo , MicroARNs/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Tejido Adiposo/metabolismo , Citocinas/metabolismo , Hipoxia/metabolismo , Inflamación/metabolismo , Obesidad/metabolismo , Proteína 1 Supresora de la Señalización de Citocinas/genética , Proteína 1 Supresora de la Señalización de Citocinas/metabolismoRESUMEN
Heterogeneity is a characteristic feature of solid tumors. Intra-tumor heterogeneity includes phenotypic diversity, epigenetic abnormalities, cell proliferation, and plasticity that eventually drives disease progression. Studying tumor heterogeneity in 2D culture is challenging as it cannot simulate the microenvironmental features, such as hypoxia, nutrient unavailability, and cell-ECM interactions. We propose the development of multicellular (tri-culture) 3D spheroids using a hanging drop method to study the non-tumorigenic (BEAS-2B) vs. tumorigenic NSCLC (A549/NCI-H460)cells' interaction with lung fibroblasts (MRC-5) and monocytes (THP-1). Unlike the non-tumorigenic model, the tumorigenic 3D spheroids show significant induction of cell proliferation, hypoxia, pluripotency markers, notable activation of cancer-associated fibroblasts, and tumor-associated macrophages. CD68+ macrophages isolated from tumorigenic spheroids exhibited profound induction of phenotypic endothelial characteristics. The results are zebrafish tumor xenograft model and by using human patient samples. This multicellular 3D tumor model is a promising tool to study tumor-stroma interaction and cellular plasticity, targeting tumor heterogeneity, and facilitating cancer therapy success against NSCLC.
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In most cancers, tumor hypoxia downregulates the expression of C-C motif chemokine 2 (CCL2), and this downregulation has been implicated in monocyte infiltration and tumor progression; however, the molecular mechanism is yet not clear. We compared non-cancerous and lung-adenocarcinoma human samples for hypoxia-inducible factor 1-alpha (HIF-1A), microRNA-210-3p (mir-210-3p) and CCL2 levels. Mechanistic studies were performed on lung adenocarcinoma cell lines and 3D tumor spheroids to understand the role of hypoxia-induced miR-210-3p in the regulation of CCL2 expression and macrophage polarization. HIF-1 A stabilization increases miR-210-3p levels in lung adenocarcinoma and impairs monocyte infiltration by inhibiting CCL2 expression. Mechanistically, miR-210-3p directly binds to the 3'untranslated region (UTR) of CCL2 mRNA and silences it. Suppressing miR-210-3p substantially downregulates the effect of hypoxia on CCL2 expression. Monocyte migration is significantly hampered in miR-210-3p mimic-transfected HIF-1A silenced cancer cells. In contrast, inhibition of miR-210-3p in HIF-1A-overexpressed cells markedly restored monocyte migration, highlighting a direct link between miR-210-3p level and tumor monocyte burden. Moreover, miR-210-3p inhibition in 3D tumor spheroids promotes monocyte recruitment and skewing towards an anti-tumor M1 phenotype. Anti-hsa-miR-210-3p-locked nucleic acid (LNA) delivery in a lung tumor xenograft zebrafish model caused tumor regression, suggesting that miR-210-3p could be a promising target for immunomodulatory therapeutic strategies against lung adenocarcinoma.
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Several studies have implicated obesity-induced macrophage-adipocyte cross-talk in adipose tissue dysfunction and insulin resistance. However, the molecular cues involved in the cross-talk of macrophage and adipocyte causing insulin resistance are currently unknown. Here, we found that a lipid-induced monokine cyclophilin-A (CyPA) significantly attenuates adipocyte functions and insulin sensitivity. Targeted inhibition of CyPA in diet-induced obese zebrafish notably reduced adipose tissue inflammation and restored adipocyte function resulting in improvement of insulin sensitivity. Silencing of macrophage CyPA or pharmacological inhibition of CyPA by TMN355 effectively restored adipocytes' functions and insulin sensitivity. Interestingly, CyPA incubation markedly increased adipocyte inflammation along with an impairment of adipogenesis, however, mutation of its cognate receptor CD147 at P309A and G310A significantly waived CyPA's effect on adipocyte inflammation and its differentiation. Mechanistically, CyPA-CD147 interaction activates NF-κB signaling which promotes adipocyte inflammation by upregulating various pro-inflammatory cytokines gene expression and attenuates adipocyte differentiation by inhibiting PPARγ and C/EBPß expression via LZTS2-mediated downregulation of ß-catenin. Moreover, inhibition of CyPA or its receptor CD147 notably restored palmitate or CyPA-induced adipose tissue dysfunctions and insulin sensitivity. All these results indicate that obesity-induced macrophage-adipocyte cross-talk involving CyPA-CD147 could be a novel target for the management of insulin resistance and type 2 diabetes.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Tejido Adiposo/metabolismo , Animales , Ciclofilina A/genética , Ciclofilinas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inflamación/metabolismo , Resistencia a la Insulina/genética , Lípido A/metabolismo , Ratones , Monocinas/metabolismo , Obesidad/metabolismo , Pez Cebra/genéticaRESUMEN
AIMS: Imidazo[1,2-a]pyridine-based analogues have recently gained significant interest because of their wide spectrum of biological activities including anti-cancer potential, however the development of targeted therapeutic candidates against non-small cell lung cancer (NSCLC) is of utmost need due to its high prevalence and poor prognosis. Herein, we have aimed to synthesized novel imidazo [1,2-a] pyridine derivatives (IMPA) by coupling with 2-amino-4H-pyran to enhance bioactivity against NSCLC. MAIN METHODS: We have designed and synthesized a series of fifteen novel imidazo [1,2-a] pyridine derivatives through molecular hybridization and studied their anti-cancer activity against in-vitro lung adenocarcinoma and 3D multicellular lung tumor spheroids. KEY FINDINGS: IMPA-2, IMPA-5, IMPA-6, IMPA-8, and IMPA-12 markedly induced cytotoxicity by notably increased NADPH oxidase (NOX) activity, which results in the induction of ROS-mediated apoptosis in A549 lung cancer cells. It caused impairment of mitochondrial membrane potential by increasing pro-apoptotic BAX, and BAK1 expressions, and decreasing anti-apoptotic BCL2 expression, along with the induction of caspase-9/3 activation, however, these attributes were compromised in presence of N-acetyl-L-cysteine (NAC), a free radical scavenger. Increased ROS production by IMPAs also promotes p53 mediated cell cycle arrest through the inactivation of p38MAPK. Reduction of tumor size in IMPAs-treated 3D multicellular lung tumor spheroids gave further validation. SIGNIFICANCE: Beside cytotoxicity, IMPAs also inhibit lung cancer cell invasion and migration, suggesting their applicability in metastatic lung cancer. Therefore, IMPA derivatives could be used as potential anti-cancer agents in treating non-small cell lung cancer.
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Adenocarcinoma del Pulmón/patología , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/patología , Puntos de Control del Ciclo Celular , Neoplasias Pulmonares/patología , Estrés Oxidativo , Piridinas/farmacología , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/metabolismo , Antineoplásicos/química , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proliferación Celular , Humanos , Imidazoles/química , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Potencial de la Membrana Mitocondrial , Piridinas/química , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
India has recorded the maximum snakebite deaths in the world. Intravenous administration of polyvalent antivenom (PAV) raised against the 'Big Four' venomous snakes of India (Naja naja, Daboia russelli, Echis carinatus, and Bungarus caeraleus) is the only choice of treatment. The WHO has recommended the evaluation of quality and safety of commercial antivenom by in vitro laboratory tests prior to their pre-clinical evaluation in animal model and therapeutic use. Therefore, in this study an attempt has been made to evaluate the quality of commercial polyvalent antivenom produced in India by simple, and affordable laboratory tests. Proteomic analysis revealed that PAVs contained 78.7-94.8% IgG/F(ab')2 and small quantities of plasma proteins. The PAVs showed batch-to-batch variations with varying amounts of undigested IgG and its aggregates, and moderate complement activation. However, absence of IgE, negligible endotoxin contamination, and recommended limit of preservative (cresol) in PAVs were observed. The PAVs contain varying proportions and least amount of venom-specific antibodies against venoms of the 'Big Four' snakes from different locales of India, and against eastern India N. kaouthia venom, respectively. The importance of independent in vitro laboratory tests for the quality control and safety assessment for improving the quality of Indian commercial PAV is reinforced.
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Antivenenos/química , Animales , Venenos Elapídicos , India , Espectrometría de Masas , Proteómica , Mordeduras de Serpientes/tratamiento farmacológico , SerpientesRESUMEN
1, 8- Naphthyridine nucleus belongs to significant nitrogen-containing heterocyclic compounds which has garnered the interest of researchers due to its versatile biological activities. It is known to be used as an antimicrobial, anti-psychotic, anti-depressant, anti-convulsant, anti- Alzheimer's, anti-cancer, analgesic, anti-inflammatory, antioxidant, anti-viral, anti-hypertensive, antimalarial, pesticides, anti-platelets, and CB2 receptor agonist, etc. The present review highlights the framework of biological properties of synthesized 1, 8-naphthyridine derivatives developed by various research groups across the globe.
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Naftiridinas/farmacología , Nitrógeno/química , Animales , Antiinfecciosos/farmacología , Antiinflamatorios/química , Anticonvulsivantes/farmacología , Antidepresivos/farmacología , Antipsicóticos/farmacología , Enoxacino/farmacología , Fluoroquinolonas/farmacología , Gemifloxacina/farmacología , Humanos , Ácido Nalidíxico/farmacología , Naftiridinas/síntesis química , Polifarmacia , Tiazoles/farmacologíaRESUMEN
Saturated free fatty acid-induced adipocyte inflammation plays a pivotal role in implementing insulin resistance and type 2 diabetes. Recent reports suggest A2A adenosine receptor (A2AAR) could be an attractive choice to counteract adipocyte inflammation and insulin resistance. Thus, an effective A2AAR agonist devoid of any toxicity is highly appealing. Here, we report that indirubin-3'-monoxime (I3M), a derivative of the bisindole alkaloid indirubin, efficiently binds and activates A2AAR which leads to the attenuation of lipid-induced adipocyte inflammation and insulin resistance. Using a combination of in silico virtual screening of potential anti-diabetic candidates and in vitro study on insulin-resistant model of 3T3-L1 adipocytes, we determined I3M through A2AAR activation markedly prevents lipid-induced impairment of the insulin signaling pathway in adipocytes without any toxic effects. While I3M restrains lipid-induced adipocyte inflammation by inhibiting NF-κB dependent pro-inflammatory cytokines expression, it also augments cAMP-mediated CREB activation and anti-inflammatory state in adipocytes. However, these attributes were compromised when cells were pretreated with the A2AAR antagonist, SCH 58261 or siRNA mediated knockdown of A2AAR. I3M, therefore, could be a valuable option to intervene adipocyte inflammation and thus showing promise for the management of insulin resistance and type 2 diabetes.
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Agonistas del Receptor de Adenosina A2/farmacología , Adipocitos/metabolismo , Indoles/farmacología , Resistencia a la Insulina , Lípidos/toxicidad , Oximas/farmacología , Receptor de Adenosina A2A/metabolismo , Células 3T3-L1 , Adipocitos/patología , Animales , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Ratones , Transducción de Señal/efectos de los fármacosRESUMEN
An acidic phospholipase A2 enzyme (NnPLA2-I) interacts with three finger toxins (cytotoxin and neurotoxin) from Naja naja venom to form cognate complexes to enhance its cytotoxicity towards rat L6 myogenic cells. The cytotoxicity was further enhanced in presence of trace quantity of venom nerve growth factor. The purified rat myoblast cell membrane protein showing interaction with NnPLA2-I was identified as vimentin by LC-MS/MS analysis. The ELISA, immunoblot and spectrofluorometric analyses showed greater binding of NnPLA2-I cognate complex to vimentin as compared to the binding of individual NnPLA2-I. The immunofluorescence and confocal microscopy studies evidenced the internalization of NnPLA2-I to partially differentiated myoblasts post binding with vimentin in a time-dependent manner. Pre-incubation of polyvalent antivenom with NnPLA2-I cognate complex demonstrated better neutralization of cytotoxicity towards L6 cells as compared to exogenous addition of polyvalent antivenom 60-240â¯min post treatment of L6 cells with cognate complex suggesting clinical advantage of early antivenom treatment to prevent cobra venom-induced cytotoxicity. The in silico analysis showed that 19-22 residues, inclusive of Asp48 residue, of NnPLA2-I preferentially binds with the rod domain (99-189 and 261-335 regions) of vimentin with a predicted free binding energy (ΔG) and dissociation constant (KD) values of -12.86â¯kcal/mol and 3.67â¯×â¯10-10â¯M, respectively; however, NnPLA2-I cognate complex showed greater binding with the same regions of vimentin indicating the pathophysiological significance of cognate complex in cobra venom-induced cytotoxicity.
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Membrana Celular/metabolismo , Venenos Elapídicos/enzimología , Fosfolipasas A2/metabolismo , Vimentina/metabolismo , Animales , Sitios de Unión , Línea Celular , Membrana Celular/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Venenos Elapídicos/farmacología , Eritrocitos/efectos de los fármacos , Cabras , Humanos , Mioblastos/efectos de los fármacos , Naja , Fosfolipasas A2/química , Ratas , Relación Estructura-Actividad , Vimentina/químicaRESUMEN
The accuracy of magnetic resonance imaging (MRI) scanning can be improved using a multifunctional nanosystem having T1-T2 dual contrast enhancement. Specifically, the combination of both T1 and T2 effects in a single system helps in acquiring cross validated information during dual mode MRI and reduces the required dose. In this study, polyethylene glycol (PEG) stabilized MnFe2O4@MnO Janus nanoparticles were developed as novel dual-mode MR imaging agents. MnO contributed to T1 contrast whereas MnFe2O4 enabled T2 contrast. The PEG molecules afforded solubility and stability to the contrast agent in water, making it acceptable for biomedical purposes. The biocompatibility of the developed nanosystem was confirmed by cell viability studies. The r2/r1 ratio remained at a suitable value, justifying the applicability of the contrast agent for dual mode MRI. Finally, the efficiency of the agent for T1-T2 contrast enhancement was confirmed through in vitro and ex vivo MRI experiments.
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The transformation of macrophages into lipid-loaded foam cells is a critical and early event in the pathogenesis of atherosclerosis. Several recent reports highlighted that induction of TLR4 signaling promotes macrophage foam cell formation; however, the underlying molecular mechanisms have not been clearly elucidated. Here, we found that the TLR4 mediated inflammatory signaling communicated with mTORC2-Akt-mTORC1 metabolic cascade in macrophage and thereby promoting lipid uptake and foam cell formation. Mechanistically, LPS treatment markedly upregulates TLR4 mediated inflammatory pathway which by activating mTORC2 induces Akt phosphorylation at serine 473 and that aggravate mTORC1 dependent scavenger receptors expression and consequent lipid accumulation in THP-1 macrophages. Inhibition of mTORC2 either by silencing Rictor expression or inhibiting its association with mTOR notably prevents LPS induced Akt activation, scavenger receptors expression, and macrophage lipid accumulation. Although suppression of mTORC1 expression by genetic knockdown of Raptor did not produce any significant change in Akt S473 phosphorylation, however, incubation with Akt activator in Rictor silenced cells failed to promote scavenger receptors expression and macrophage foam cell formation. Thus, present research explored the signaling pathway involved in inflammation-induced macrophage foam cells formation and therefore, targeting this pathway might be useful for preventing macrophage foam cell formation.
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Células Espumosas/metabolismo , Inflamación/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Humanos , Diana Mecanicista del Complejo 2 de la Rapamicina/química , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Células THP-1 , Receptor Toll-Like 4/metabolismoRESUMEN
Dramatic increase of diabetes over the globe is in tandem with the increase in insulin requirement. This is because destruction and dysfunction of pancreatic ß-cells are of common occurrence in both Type1 diabetes and Type2 diabetes, and insulin injection becomes a compulsion. Because of several problems associated with insulin injection, orally active insulin mimetic compounds would be ideal substitute. Here we report a small molecule, a peroxyvanadate compound i.e. DmpzH[VO(O2)2(dmpz)], henceforth referred as dmp, which specifically binds to insulin receptor with considerable affinity (KD-1.17µM) thus activating insulin receptor tyrosine kinase and its downstream signaling molecules resulting increased uptake of [14C] 2 Deoxy-glucose. Oral administration of dmp to streptozotocin treated BALB/c mice lowers blood glucose level and markedly stimulates glucose and fatty acid uptake by skeletal muscle and adipose tissue respectively. In db/db mice, it greatly improves insulin sensitivity through excess expression of PPARγ and its target genes i.e. adiponectin, CD36 and aP2. Study on the underlying mechanism demonstrated that excess expression of Wnt3a decreased PPARγ whereas dmp suppression of Wnt3a gene increased PPARγ expression which subsequently augmented adiponectin. Increased production of adiponectin in db/db mice due to dmp effected lowering of circulatory TG and FFA levels, activates AMPK in skeletal muscle and this stimulates mitochondrial biogenesis and bioenergetics. Decrease of lipid load along with increased mitochondrial activity greatly improves energy homeostasis which has been found to be correlated with the increased insulin sensitivity. The results obtained with dmp, therefore, strongly indicate that dmp could be a potential candidate for insulin replacement therapy.
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Complejos de Coordinación/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Resistencia a la Insulina , Receptor de Insulina/agonistas , Compuestos de Vanadio/uso terapéutico , Células 3T3 , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Tejido Adiposo/metabolismo , Animales , Glucemia/metabolismo , Antígenos CD36/genética , Antígenos CD36/metabolismo , Células Cultivadas , Complejos de Coordinación/uso terapéutico , Diabetes Mellitus Experimental/metabolismo , Ácidos Grasos/sangre , Femenino , Hipoglucemiantes/síntesis química , Hipoglucemiantes/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , Unión Proteica , Receptor de Insulina/metabolismo , Triglicéridos/sangre , Compuestos de Vanadio/síntesis química , Compuestos de Vanadio/farmacología , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismoRESUMEN
Adiponectin secreted from adipocytes is an anti-diabetic and anti-atherogenic adipokine. Adiponectin level is known to fall significantly in obesity induced type 2 diabetes which worsen insulin sensitivity because of aberrant lipid management. However, underlying mechanism of adiponectin decrease in obese diabetic condition is yet unclear. We report here that lowering of plasma adiponectin coincided with the higher Fetuin A (FetA) level in high fat diet (HFD) induced obese diabetic mice. Knock down of FetA gene (FetAKD) elevated adiponectin level markedly in HFD mice, while reinforcement of FetA into FetAKDHFD mice reduced its level again. These results indicate FetA's involvement in the lowering of adiponectin level in obesity induced diabetic mice. Our findings to understand how FetA could affect adiponectin decrease demonstrated that FetA could enhance Wnt3a expression in the adipocyte of HFD mice. FetA addition to 3T3L1 adipocyte incubation elevated Wnt3a expression in a dose dependent manner. Overexpression of Wnt3a by FetA inhibited PPARγ and adiponectin. FetA failed to reduce PPARγ and adiponectin in Wnt3a gene knocked down 3T3L1` adipocytes. All these suggest that FetA mediate its inhibitory effect on adiponectin through Wnt3a-PPARγ pathway. Inhibition of adiponectin expression through FetA and Wnt3a significantly compromised with the activation of AMPK and its downstream signalling molecules which adversely affected lipid management causing loss of insulin sensitivity. Downregulation of adiponectin in inflamed adipocyte by FetA through the mediation of Wnt3a and PPARγ is a new report.
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Adipocitos/inmunología , Adiponectina/inmunología , Obesidad/inmunología , PPAR gamma/inmunología , Transducción de Señal , Proteínas Wnt/inmunología , alfa-2-Glicoproteína-HS/inmunología , Células 3T3-L1 , Animales , Células Cultivadas , Inflamación/inmunología , Resistencia a la Insulina , Lípidos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB CRESUMEN
Metal contamination from coal ashes (CAs) is widely recognized as a significant environmental concern. To learn more about metal detoxification and accumulation potential of earthworm species, metal-rich tea factory coal ashes (TFCA) were fed to Eisenia fetida and Lampito mauritii by employing a fluorescent tag detection method. Fascinatingly, on feeding fluorescence probed Zn and Cd along with cow dung to Eisenia fetida, the detection of the gut-proteins with a molecular mass higher than 100 kDa was a distinct evidence of metal binding. Significant increases were observed in the content of humified organic C [humic acid (HAC) and fulvic acid C (FAC)] and degree of humification during vermicomposting. Concurrently, considerably large amount of toxic metals (Cr, Cd, Pb, and Zn) was transformed from exchangeable to recalcitrant (organic matter and mineral bound) fractions. Moreover, total metal concentrations were reduced with high removal efficiency upon vermicomposting.
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Cadmio/metabolismo , Ceniza del Carbón/metabolismo , Compostaje/métodos , Inactivación Metabólica , Oligoquetos/metabolismo , Zinc/metabolismo , Animales , Benzopiranos/análisis , Cadmio/análisis , Ceniza del Carbón/química , Sustancias Húmicas/análisis , Mucosa Intestinal/metabolismo , Oligoquetos/efectos de los fármacos , Unión Proteica , Zinc/análisisRESUMEN
Skeletal muscle and adipose tissues are known to be two important insulin target sites. Therefore, lipid induced insulin resistance in these tissues greatly contributes in the development of type 2 diabetes (T2D). Ferulic acid (FRL) purified from the leaves of Hibiscus mutabilis, showed impressive effects in preventing saturated fatty acid (SFA) induced defects in skeletal muscle cells. Impairment of insulin signaling molecules by SFA was significantly waived by FRL. SFA markedly reduced insulin receptor ß (IRß) in skeletal muscle cells, this was affected due to the defects in high mobility group A1 (HMGA1) protein obtruded by phospho-PKCε and that adversely affects IRß mRNA expression. FRL blocked PKCε activation and thereby permitted HMGA1 to activate IRß promoter which improved IR expression deficiency. In high fat diet (HFD) fed diabetic rats, FRL reduced blood glucose level and enhanced lipid uptake activity of adipocytes isolated from adipose tissue. Importantly, FRL suppressed fetuin-A (FetA) gene expression, that reduced circulatory FetA level and since FetA is involved in adipose tissue inflammation, a significant attenuation of proinflammatory cytokines occurred. Collectively, FRL exhibited certain unique features for preventing lipid induced insulin resistance and therefore promises a better therapeutic choice for T2D.