PTHLH and Insulin resistance: PTH/PTHrP-induced inflammation can trigger insulin resistance: the inflammatory stimulus stimulates phosphorylation of specific serine residues in insulin-receptor substrate (IRS)-1 before it is degraded by the UPS [215] and the reduction phosphorylated-Akt induces the expression of specific E3 ubiquitin ligases that mark proteins for degradation [213,215].