SOX2 and obesity due to melanocortin 4 receptor deficiency: Additionally, the elevated IL-6 induced by obesity activates the SOCS3/STAT3 signaling pathway, inhibiting the expression of Zinc Finger Protein 637 (Zfp637) and subsequently downregulating SRY-box transcription factor 2 (SOX2) expression, thereby disrupting spermatogonial cell differentiation in mice [97].