BCL2 and systemic lupus erythematosus: Similarly, Yan and colleagues reported that calcitriol (2 μg/kg, ip for 4 weeks) can ameliorate cognitive decline in mice with systemic lupus erythematosus by hindering hippocampal neuron apoptosis (lowering hippocampal cleaved caspase-3 and increasing Bcl-2) (Yan et al. 2019).