Structural characterization of an oligosaccharide from Cistanche deserticola and its protective effect on diabetes-induced spermatogenic dysfunction

Diabetes-induced spermatogenic dysfunction (DSD), a major contributor to male infertility, lacks effective treatments. Cistanche deserticola oligosaccharides are potential therapeutic candidates, but specific, structurally characterized compounds remain underexplored. This study isolated a novel homogeneous oligosaccharide, CDOs-A1, with an approximate molecular weight of 1390 Da, from the ethanol supernatant of C. deserticola polysaccharide extraction. Structural analysis identified CDOs-A1 as primarily an α-(1 → 4)-linked glucan backbone branched with α-(1 → 6)-linked glucose residues, and determined it to be amorphous in nature. In vitro, CDOs-A1 significantly protected TM4 Sertoli cells from high glucose-induced injury. The most significant finding was that CDOs-A1 mitigated oxidative stress and apoptosis, likely by activating the Keap1-Nrf2/HO-1 signaling pathway. This research elucidates the structural characteristics of a novel C. deserticola oligosaccharide and in vitro evidence of its protective effects against cellular damage related to DSD, offering a preliminary basis for its future therapeutic development.