Catecholamines (CA) are considered to play key roles in acute stress responses, but they also regulate important functions of the nervous, immune, and endocrine systems and are essential for body homeostasis and health. In Swiss mice (an outbred strain) with haploinsufficiency of the tyrosine hydroxylase gene (Th, TH-HZ), which encodes the rate-limiting enzyme of catecholamine synthesis, impairments in homeostatic system functions and a reduced lifespan have been reported. Moreover, these homeostatic alterations are exacerbated when these animals are exposed to acute restraint stress. Nonetheless, the effects of this genetic modification on an inbred strain, such as C57BL/6J, are undetermined. Given that the genetic background of mice can affect the phenotype of any genetic modification, this work aimed to characterize how behavioral responses, immunity, and the oxidative state in C57BL/6J mice are altered by Th haploinsufficiency under basal conditions after being subjected to 10 min of acute restraint stress. Sex differences were also considered. Compared with their WT counterparts, TH-HZ C57BL/6J animals exhibit behavioral impairments, immunosenescence, and oxidative stress under basal conditions. After stress, TH-HZ animals (both sexes) exhibit deteriorated behavior and immune functions. Therefore, Th haploinsufficiency in the inbred C57BL/6J strain triggers impairments in behavior, immunity, and the redox state. These findings corroborate the role of CA in maintaining regulatory system functions and highlight the importance of mouse strains in basic research.

Inflammatory–oxidative stress is known to be pivotal in the pathobiology of Alzheimer’s disease (AD), but the involvement of this stress at the peripheral level in the disease’s onset has been scarcely studied. This study investigated the pro-inflammatory profile and oxidative stress parameters in peritoneal leukocytes from female triple-transgenic mice for AD (3xTgAD) and non-transgenic mice (NTg). Peritoneal leukocytes were obtained at 2, 4, 6, 12, and 15 months of age. The concentrations of TNFα, INFγ, IL-1β, IL-2, IL-6, IL-17, and IL-10 released in cultures without stimuli and mitogen concanavalin A and lipopolysaccharide presence were measured. The concentrations of reduced glutathione (GSH), oxidized glutathione (GSSG), lipid peroxidation, and Hsp70 were also analyzed in the peritoneal cells. Our results showed that although there was a lower release of pro-inflammatory cytokines by 3xTgAD mice, this response was uncontrolled and overstimulated, especially at a prodromal stage at 2 months of age. In addition, there were lower concentrations of GSH in leukocytes from 3xTgAD and higher amounts of lipid peroxides at 2 and 4 months, as well as, at 6 months, a lower concentration of Hsp70. In conclusion, 3xTgAD mice show a worse pro-inflammatory response and higher oxidative stress than NTg mice during the prodromal stages, potentially supporting the idea that Alzheimer’s disease could be a consequence of peripheral alteration in the leukocyte inflammation–oxidation state.