The Janus kinase (JAK)–signal transducer and activator of transcription 3 (STAT3) signalling pathway is activated by hyperglycaemia, and STAT3 phosphorylation enhances HDAC1 and downregulates autophagy markers, including P62.189 HDAC3 is highly expressed in the retina tissues of DR mice. Here, STAT3 is linked to Hyperglycemia.