Transmission electron microscopy

showed that in the control group the microstructure of the neurons was normal, mitochondria were well arranged and distributed unevenly and orderly, mitochondrial cristae were compact, with a well-defined double membrane structure without swelling. The AHH group showed significant injuries than the control group, including a remarkable cell loss and karyopyknosis, significantly decreased mitochondria that were also swollen, without cristae and with a fragmented double membrane structure. Furthermore, some channels of the endoplasmic network were atypically swollen. Crocin pretreatment significantly reduced injuries compared with the AHH group, including cell loss and karyopyknosis in hippocampal neurons, with a significantly higher number of mitochondria in all the crocin-treated groups, decreased mitochondrial swelling, and with an intact double membrane structure and cristae, suggesting a protection of the mitochondrial structure, especially in the HHG that showed the best effect