A non-naturally occurring melanocortin ligand comprising a melanocortin analog coupled to a degradation-resistant C-terminal extension and an N-terminal extension, the non-naturally occurring melanocortin ligand comprising Formula I: Y 1 -Y 2 -Y 3 -R 1 -R 2 -R 3 -R 4 -R 5 -R 6 -R 7 -X 1 -X 2 -X 3 ( Formula I), wherein the melanocortin analog comprises R 1 to R 7, wherein: R 1 is absent or is selected from the group consisting of cysteine, norleucine, acetylated norleucine, acetylated cysteine, D-phenylalanine, acetylated D-phenylalanine, succinic acid, o-phthalic acid, tyrosine, aspartic acid, glutaric acid, CO-cis-CH=CH-CO, an n -pentanoyl group, and an n- hexanoyl group; R 2 is absent or is selected from the group consisting of proline, aspartic acid, glutamic acid, glycine, cysteine, norleucine, arginine, succinic acid, glutaric acid, CO-cis-CH=CH-CO, an n -pentanoyl group, and an n- hexanoylgroup; R 3 is selected from the group consisting of histidine, histidine methylated at positions 1 or 3, D-proline, L-proline, D-Nal, L-Nal, succinic acid, t ButGly, Hyp(Bzl), Mamb, Oic, norleucine, Aba, β-alanine, and Tic; R 4 is selected from the group consisting of histidine, D-phenylalanine, L-phenylalanine, D-Nal, pCl-D-Phe, and (o-Phe)Phe; R 5 is selected from the group consisting of arginine, homoarginine, ornithine, alanine, proline, Pip, Nip, Tic, Phg, Sar, and Azt; R 6 is selected from D-tryptophan, L-tryptophan, D-Nal, L-Nal, Tic, and Bip; R 7 is selected from the group consisting of cysteine, lysine, and 2,3-diamino-propionic acid; wherein if R 3 is Aba, then R 4 is selected from the group consisting of D-Phe, D-Nal, and pCl-D-Phe; and wherein if R 2 is an n -pentanoyl group or an n -hexanoyl group, then R 1, Y 1, Y 2, and Y 3 are absent; wherein the N-terminal extension comprises Y 1 to Y 3: Y 1 is absent or is selected from the group consisting of D-threonine, L-threonine, D-proline, and L-proline; Y 2 is absent or is selected from the group consisting of D-threonine, L-threonine, D-proline, L-proline, and a piperazin-2-one ring; Y 3 is absent or is selected from the group consisting of cysteine, D-threonine, L-threonine, D-proline, L-proline, and a piperazin-2-one ring; wherein the degradation-resistant C-terminal extension comprises X 1 to X 3 and X 1 is D-threonine,; X 2 is D-proline,; X 3 is D-threonine wherein the melanocortin ligand is cyclized through a moiety selected from the group consisting of: when R 2 is cysteine and R 7 is cysteine a disulfide bond is formed between R 2 and R 7; when R 2 is glutamic acid or aspartic acid and R7 is lysine a side-chain lactam bridge is formed between R 2 and R 7; and when R 2 or R 3 is succinic acid and R 7 is 2,3-diamino-propionic acid a lactam closure is formed between R 2 or R 3 and R 7. R 1 is absent or is selected from the group consisting of cysteine, norleucine, acetylated norleucine, acetylated cysteine, D-phenylalanine, acetylated D-phenylalanine, succinic acid, o-phthalic acid, tyrosine, aspartic acid, glutaric acid, CO-cis-CH=CH-CO, an n -pentanoyl group, and an n- hexanoyl group; R 2 is absent or is selected from the group consisting of proline, aspartic acid, glutamic acid, glycine, cysteine, norleucine, arginine, succinic acid, glutaric acid, CO-cis-CH=CH-CO, an n -pentanoyl group, and an n- hexanoylgroup; R 3 is selected from the group consisting of histidine, histidine methylated at positions 1 or 3, D-proline, L-proline, D-Nal, L-Nal, succinic acid, t ButGly, Hyp(Bzl), Mamb, Oic, norleucine, Aba, β-alanine, and Tic; R 4 is selected from the group consisting of histidine, D-phenylalanine, L-phenylalanine, D-Nal, pCl-D-Phe, and (o-Phe)Phe; R 5 is selected from the group consisting of arginine, homoarginine, ornithine, alanine, proline, Pip, Nip, Tic, Phg, Sar, and Azt; R 6 is selected from D-tryptophan, L-tryptophan, D-Nal, L-Nal, Tic, and Bip; R 7 is selected from the group consisting of cysteine, lysine, and 2,3-diamino-propionic acid; Y 1 is absent or is selected from the group consisting of D-threonine, L-threonine, D-proline, and L-proline; Y 2 is absent or is selected from the group consisting of D-threonine, L-threonine, D-proline, L-proline, and a piperazin-2-one ring; Y 3 is absent or is selected from the group consisting of cysteine, D-threonine, L-threonine, D-proline, L-proline, and a piperazin-2-one ring; X 1 is D-threonine,; X 2 is D-proline,; X 3 is D-threonine when R 2 is cysteine and R 7 is cysteine a disulfide bond is formed between R 2 and R 7; when R 2 is glutamic acid or aspartic acid and R7 is lysine a side-chain lactam bridge is formed between R 2 and R 7; and when R 2 or R 3 is succinic acid and R 7 is 2,3-diamino-propionic acid a lactam closure is formed between R 2 or R 3 and R 7.