Exosomes of adipose-derived mesenchymal stem cells loaded with globular adiponectin improve islet function for type 2 diabetes

Figure 6 Protective effects of globular adiponectin, exosome, and globular adiponectin-loaded exosomes on palmitic acid-induced injury in INS-1 cells. A: The impact of varying palmitate concentrations on INS-1 cells was assessed using the Cell Counting Kit-8 method (n = 3); B: Cell Counting Kit-8 was employed to determine the survival rates of globular adiponectin (gAd), exosome (Exo), and gAd-loaded Exo following an 18-hour exposure to 350 μmol/L palmitic acid (n = 3); C: Fluorescence images of INS-1 cell illustrating intracellular reactive oxygen species levels (n = 3; scale bars = 100 μm); D: The fluorescence intensity bar chart of DCFH-DA; E: After treatment with gAd, Exo, or gAd-loaded Exos, the mitochondrial damage levels in palmitic acid-treated or control INS-1 cells were evaluated using a mitochondrial membrane potential detection kit (JC-1). When the mitochondrial membrane potential is low, JC-1 exists in a monomeric form, cannot accumulate in the mitochondrial matrix, and produces green fluorescence. When the mitochondrial membrane potential is high, JC-1 aggregates in the mitochondrial matrix to form polymers, resulting in red fluorescence (n = 3; scale bars = 50 μm); F: The bar chart of JC-1 aggregate/monomer; G: Fluorescence images indicating cell apoptosis (Annexin V-FITC, green; PI, red; scale bars = 50 μm). The cell nuclei were stained with DAPI (blue). ^aP < 0.05, ^bP < 0.01, ^cP < 0.001 vs the model group respectively; ^eP < 0.001, ^fP < 0.01, ^gP < 0.0001 vs the control group respectively. PA: Palmitic acid; Exo: Exosome; gAd: Globular adiponectin.