The mRNA expression levels of ER stress markers (Xbp1, sXbp1, Atf4, Atf6, and Grp78) were significantly higher in the ASCs treated with hypertrophic obesity adipocyte-derived EVs than in the ASCs treated with control adipocyte-derived EVs (Figure 4(d)). Here, XBP1 is linked to obesity due to melanocortin 4 receptor deficiency.