Effects of antiretroviral drugs, tunicamycin, and thapsigargin on the expression of FGF21, CHOP10, and HSPA5 mRNAs and FGF21 release into the cell culture medium in human LHCN-M2 skeletal muscle cells differentiated in culture. LHCN-M2 myotubes differentiated in culture were treated for 24 h, as indicated, with the following drugs: zidovudine (AZT), 100 μM; stavudine (D4T), 100 μM; tenofovir disoproxil fumarate (TDF), 5 μM; nevirapine (NVP), 20 μM; efavirenz (EFV), 50 μM; rilpivirine (RPV), 10 μM; lopinavir-ritonavir 4:1 (LPV/r), 20 μM; ritonavir (RTV), 20 μM; lopinavir (LPV), 20 μM; nelfinavir (NFV), 20 μM; atazanavir (ATV), 50 μM; maraviroc (MRV), 4 μM; tunicamycin (TUN), 2 μM; thapsigargin (THAP), 2 μM. (A) mRNA levels are presented as means ± SEM from 4 to 5 independent experiments and are expressed relative to values for control cells (defined as 1). (B) FGF21 protein levels in cell culture medium. Data are presented as means ± SEM from 4 to 5 independent experiments. *, P < 0.05; **, P < 0.01, and ***, P < 0.001 for each drug treatment versus control.