Agent and cell-type specificity in the induction of insulin resistance by HIV protease inhibitors

Ben-Romano, Ronit; Rudich, Assaf; Török, Dóra; Vanounou, Sharon; Riesenberg, Klaris; Schlaeffer, Francisc; Klip, Amira; Bashan, Nava

doi:10.1097/00002030-200301030-00005

Cited by 78 publications

(73 citation statements)

References 51 publications

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“…3T3-L1 pre-adipocytes (American Type Culture Collection) were grown in DMEM and differentiated exactly as previously described [15,16,20]. Fully differentiated cells (10-12 days after induction of differentiation) were incubated in serum-free DMEM supplemented with 0.5% RIA-grade BSA, with or without 30 µmol/l of nelfinavir, for 18 h. The final nelfinavir medium concentration was achieved by the appropriate dilution of a 100 mmol/l stock solution prepared in 100% ethanol.…”

Section: Materials and Reagentsmentioning

confidence: 99%

“…Cells were lysed as described above. For immunoprecipitation, 0.5 mg of celllysate protein was used and assayed as described in [16]. PI 3-kinase activity was measured following the protocol described by Hadari et al [22], using phosphatidylinositol and [γ-32 P] ATP as substrates.…”

Section: Materials and Reagentsmentioning

confidence: 99%

“…However, it is not clear whether this represents selectivity of nelfinavir to the insulin signalling cascade or the response of a sub-population of cells within the cell culture [23]. Consistent with the latter possibility is the finding that 3T3-L1 pre-adipocytes are resistant to the effects of nelfinavir, whereas their differentiated counterparts are not [16].…”

Section: Nelfinavir Impairs Propagation Of the Insulin Signal Downstrmentioning

confidence: 99%

“…None of these cellular mechanisms is necessarily mutually exclusive of the others [16,17]. For example, nelfinavir, saquinavir and indinavir all acutely inhibit GLUT4-mediated glucose uptake, but only nelfinavir induced insulin resistance after an 18-h incubation [16]. Indeed, we have recently reported that differentiated 3T3-L1 adipocytes that were exposed to the HIV protease inhibitor nelfinavir for 18 h exhibited enhanced basal lipolysis and impaired responsiveness to insulin [15].…”

Section: Introductionmentioning

confidence: 98%

“…These include induction of adipocyte apoptosis [9], interference with terminal adipocyte differentiation [9,10,11], direct inhibition of the insulin-responsive glucose transporter GLUT4 [12,13,14] and interference with intracellular insulin signals leading to the deregulation of glucose and lipid metabolism [15]. None of these cellular mechanisms is necessarily mutually exclusive of the others [16,17]. For example, nelfinavir, saquinavir and indinavir all acutely inhibit GLUT4-mediated glucose uptake, but only nelfinavir induced insulin resistance after an 18-h incubation [16].…”

Section: Introductionmentioning

confidence: 99%

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Nelfinavir-induced insulin resistance is associated with impaired plasma membrane recruitment of the PI 3-kinase effectors Akt/PKB and PKC-?

et al. 2004

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Aims/hypothesis. Chronic exposure of 3T3-L1 adipocytes to the HIV protease inhibitor nelfinavir induces insulin resistance, recapitulating key metabolic alterations of adipose tissue in the lipodystrophy syndrome induced by these agents. Our goal was to identify the defect in the insulin signal transduction cascade leading to nelfinavir-induced insulin resistance. Methods. Fully differentiated 3T3-L1 adipocytes were exposed to 30 µmol/l nelfinavir for 18 h, after which the amount, the phosphorylation and the localisation of key proteins in the insulin signalling cascade were evaluated.Results. Insulin-induced interaction of phosphatidylinositol 3′-kinase (PI 3-kinase) with IRS proteins was normal in cells treated with nelfinavir, as was IRS-1-associated PI 3-kinase activity. Yet insulin-induced phosphorylation of Akt/protein kinase B (PKB), p70S6 kinase and extracellular signal-regulated kinase 1/2 was significantly impaired. This could not be attributed to increased protein phosphatase 2A activity or to increased expression of phosphoinositide phosphatases (SHIP2 or PTEN). However, insulin failed to induce translocation of the PI 3-kinase effectors Akt/PKB and protein kinase C-ζ (PKC-ζ) to plasma membrane fractions of nelfinavir-treated adipocytes. Conclusions/interpretation. We therefore conclude that nelfinavir induces a defect in the insulin signalling cascade downstream of the activation of PI 3-kinase. This defect manifests itself by impaired insulin-mediated recruitment of Akt/PKB and PKC-ζ to the plasma membrane.

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Section: Materials and Reagentsmentioning

confidence: 99%

Section: Materials and Reagentsmentioning

confidence: 99%

Section: Nelfinavir Impairs Propagation Of the Insulin Signal Downstrmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

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Nelfinavir-induced insulin resistance is associated with impaired plasma membrane recruitment of the PI 3-kinase effectors Akt/PKB and PKC-?

et al. 2004

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HIV‐1 Protease Inhibitors as Antiretroviral Agents

Gulnik

Afonina

Eissenstat

2009

Enzyme Inhibition in Drug Discovery and Development

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A lectin‐based gold nanoparticle assay for probing glycosylation of glycoproteins

Sánchez-Pomales

Morris

Falabella

et al. 2012

Biotech & Bioengineering

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We report a glycoanalysis method in which lectins are used to probe the glycans of therapeutic glycoproteins that are adsorbed on gold nanoparticles. A model mannose-presenting glycoprotein, ribonuclease B (RNase B), and the therapeutic monoclonal antibody (mAb) rituximab, were found to adsorb spontaneously and non-specifically to bare gold nanoparticles such that glycans were accessible for lectin binding. Addition of a multivalent binding lectin, such as concanavalin A (Con A), to a solution of the modified gold nanoparticles resulted in cross-linking of the nanoparticles. This phenomenon was evidenced within 1 min by a change in the hydrodynamic diameter, D(H), measured by dynamic light scattering (DLS) and a shift and increase in absorbance of the plasmon resonance band of the gold nanoparticles. By combining the sugar-binding specificity and the cross-linking capabilities of lectins, the non-specific adsorption of glycoproteins to gold surfaces, and the unique optical reporting properties of gold nanoparticles, a glycosylation pattern of rituximab could be generated. This assay provides advantages over currently used glycoanalysis methods in terms of short analysis time, simplicity of the conjugation method, convenience of simple spectroscopic detection, and feasibility of providing glycan characterization of the protein drug product by using a variety of binding lectins.

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Agent and cell-type specificity in the induction of insulin resistance by HIV protease inhibitors

Cited by 78 publications

References 51 publications

Nelfinavir-induced insulin resistance is associated with impaired plasma membrane recruitment of the PI 3-kinase effectors Akt/PKB and PKC-?

Nelfinavir-induced insulin resistance is associated with impaired plasma membrane recruitment of the PI 3-kinase effectors Akt/PKB and PKC-?

HIV‐1 Protease Inhibitors as Antiretroviral Agents

A lectin‐based gold nanoparticle assay for probing glycosylation of glycoproteins

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