- Miyagishima, Kiyoharu J;
- Sharma, Ruchi;
- Nimmagadda, Malika;
- Clore-Gronenborn, Katharina;
- Qureshy, Zoya;
- Ortolan, Davide;
- Bose, Devika;
- Farnoodian, Mitra;
- Zhang, Congxiao;
- Fausey, Andrew;
- Sergeev, Yuri V;
- Abu-Asab, Mones;
- Jun, Bokkyoo;
- Do, Khanh V;
- Kautzman Guerin, Marie-Audrey;
- Calandria, Jorgelina;
- George, Aman;
- Guan, Bin;
- Wan, Qin;
- Sharp, Rachel C;
- Cukras, Catherine;
- Sieving, Paul A;
- Hufnagel, Robert B;
- Bazan, Nicolas G;
- Boesze-Battaglia, Kathleen;
- Miller, Sheldon;
- Bharti, Kapil
Late-onset retinal degeneration (L-ORD) is an autosomal dominant disorder caused by a missense substitution in CTRP5. Distinctive clinical features include sub-retinal pigment epithelium (RPE) deposits, choroidal neovascularization, and RPE atrophy. In induced pluripotent stem cells-derived RPE from L-ORD patients (L-ORD-iRPE), we show that the dominant pathogenic CTRP5 variant leads to reduced CTRP5 secretion. In silico modeling suggests lower binding of mutant CTRP5 to adiponectin receptor 1 (ADIPOR1). Downstream of ADIPOR1 sustained activation of AMPK renders it insensitive to changes in AMP/ATP ratio resulting in defective lipid metabolism, reduced Neuroprotectin D1(NPD1) secretion, lower mitochondrial respiration, and reduced ATP production. These metabolic defects result in accumulation of sub-RPE deposits and leave L-ORD-iRPE susceptible to dedifferentiation. Gene augmentation of L-ORD-iRPE with WT CTRP5 or modulation of AMPK, by metformin, re-sensitize L-ORD-iRPE to changes in cellular energy status alleviating the disease cellular phenotypes. Our data suggests a mechanism for the dominant behavior of CTRP5 mutation and provides potential treatment strategies for L-ORD patients.