Described herein is the identification of primate-specific glial cell line-derived neurotrophic factor opposite strand (GDNFOS) transcripts and encoded peptides. In particular embodiments, provided herein are three GDNFOS antisense transcripts, referred to as GDNFOS-1, GDNFOS-2 and GDNFOS-3. The GDNFOS-3 transcript encodes an ORF of 105 amino acids. Compositions comprising the GDNFOS transcripts and peptides are also provided by the present disclosure. Further provided are methods of treating a neurodegenerative or peripheral organ disease in a subject by administering a therapeutically effective amount of the disclosed GDNFOS nucleic acid molecules, peptides or compositions.