L-Lactate Protects Skin Fibroblasts against Aging-Associated Mitochondrial Dysfunction via Mitohormesis

Figure 6

mTOR, senescence, and autophagy in high-passage fibroblasts. (a) Relative ratio of phosphorylated/total S6 ribosomal protein in aged fibroblasts. (b) Percentage of aged fibroblasts positive for senescence-associated β-galactosidase staining. (c) Ratio of LC3bII/LC3bI isoforms in intact aged fibroblasts (basal) or after 6-hour treatment with 50 μM chloroquine (flux) (control fibroblasts: passage 18 (L0); fibroblasts cultured in constant 5 mM L-lactate: passage 18 (LC); and fibroblasts exposed to twice a week pulses of 5 mM L-lactate: passage 18 (LI); ^∗significantly different from L0; ).

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