Figure 5. Glutamine deprivation modulates mTOR activation.
(A) Primary murine chondrocytes were cultured in media containing 4 mM glutamine or 0 mM glutamine for 24 hr. Cells were then treated with IL-1β (10 ng/mL). After 24 hr, lysates were collected, and immunoblotting was performed for pAKT (60kDa) and total Akt (58kDa). (B) Under similar conditions, immunoblotting was performed for pS6 and total S6 (32kDa). (C–D) Primary murine chondrocytes were cultured in media containing 4 mM glutamine or 0 mM glutamine for 24 hr. Cells were then treated with IL-1β (10 ng/mL) in the presence or absence of rapamycin 50 nM for 24 hr. Gene expression of Il6 and Mmp13 was measured by quantitative PCR. Results from one representative experiment. n=4. One-way ANOVA was performed followed by Tukey’s multiple comparisons test. C:****p<0.0001.