Pleiotropic Effects of Taurine on Nematode Model for Down Syndrome

Taurine is traditionally used to treat Down Syndrome (DS); however, the actual foundation for this treatment is not well understood. DS patients suffer from disturbance of the proteostasis network (PN) due to aberrant calcium signaling, which eventually causes endoplasmic reticulum stress (ERS). Taurine has been suggested to play a role in modulating calcium homeostasis and ERS. This study examined whether taurine affects DS symptoms using C. elegans - a DS model in which calcineurins, Ca²⁺/calmodulin-dependent protein phosphatase is mutated to null. The DS nematode model has short body length, slow growth, fertility defects, serotonin-resistant egg-laying defects, and faulty thermal sensing. This study focused on whether taurine may ameliorate the severity of DS at the whole-body level, including reduction in ERS. When treated with taurine, DS nematodes appeared to have lower levels of ERS and phenotypes closer to the wild type. DS nematodes also showed improved egg laying efficiency and thermal sensing index comparable to the wild type. Our findings offer a new perspective on the effectiveness of taurine in treating DS and designing therapeutic strategies to lower ERS and restore disrupted PN.