4th International Workshop on Adverse Drug Reactions and Lipodystrophy in HIV 22-25 September 2002, San Diego, CA, USA

STAVUDINE AND DIDANOSINE PARTLY REVERSED THE ADVERSE EFFECTS OF INDINAVIR ON CELL DIFFERENTIATION AND RESPONSE TO INSULIN BUT ENHANCED APOPTOSIS OF CULTURED ADIPOCYTES

Antiviral Therapy 2002; 7:L6 (abstract 9)

M Caron, M Auclair, M Kornprobst and J Capeau
INSERM U 402, Faculté de Médecine Saint-Antoine Paris, France

OBJECTIVES: We previously observed that the protease inhibitor (PI) indinavir induced adverse effects on 3T3-F442A adipocyte functions. We evaluated the in vitro effects of two nucleoside reverse transcriptase inhibitors (NRTIs), stavudine and didanosine, used alone or in combination with 15 μM indinavir on adipose cell differentiation, lipid accumulation, response to insulin and survival.

METHODS: Cell differentiation was assessed by adipocyte counting and protein expression of adipogenic transcription factors; cell response to insulin by the activation of ERK 1/2 and Akt/PKB; lipid accumulation by oil red staining and lipogenesis from [¹⁴C] glucose; apoptosis by flow cytometry. Nuclear alterations were vizualized by confocal or conventional microscopy using lamin A/C and SREBP-1 antibodies.

RESULTS: Ten days exposure of 3T3-F442A adipocytes to a clinically relevant concentration of stavudine or didanosine (10 μM) altered neither adipose cell differentiation, as shown by the similar number of newly formed adipocytes and the unaltered expression of the transcription factors SREBP-1, PPARγ and C/EBPα, nor cell response to insulin, as shown by the normal activation of ERK 1/2 and Akt/PKB. However, lipid accumulation was impaired in stavudine-treated adipocytes, as shown by the 26% and 40% decrease in lipid content and maximal insulin-stimulated lipogenesis, respectively. Stavudine and didanosine promoted cell apoptosis (17 ±1 and 12 ±5% of apoptotic cells versus 2.8 ±0.3 in control cells). The proapoptotic effects of stavudine and indinavir were additive (24 ±3% versus 9 ±2 % in indinavir-treated cells). Conversely, the NRTIs partly reversed the indinavir-induced altered cell differentiation (measured by cell counting, lipid staining and expression of SREBP-1, PPARγ and C/EBPα) and insulin activation of ERK1/2 and Akt/PKB. Furthermore, the NRTIs partly prevented the indinavir-induced alteration of nuclear localization of SREBP-1. The PPARγ agonist rosiglitazone almost totally prevented the adverse effects of indinavir and NRTIs used alone or in combination, in particular on lipid content and apoptosis.

CONCLUSIONS: The results indicated that in cultured adipocytes stavudine and didanosine did not alter cell differentiation, though they moderately impaired lipid accumulation and promoted apoptosis. Cell loss was further increased when stavudine was used in combination with indinavir. However, stavudine and didanosine partly reversed the indinavir-induced alteration of cell differentiation and insulin resistance, possibly by restoring the intra-nuclear penetration of SREBP-1.

Presenting author: J Capeau

2002-09-22
9

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