Chronic stress induction in immunosuppression
and splenocyte apoptosis
is commonly associated with increased susceptibility to various diseases.
Lycopene (LYC) is a member of the carotenoid family with immune restoration
and anti-apoptotic function. However, little is known about the mechanisms
underlying the protective roles of LYC against spleen injury induced
by chronic stress. Herein, male Wistar rats were undergoing chronic
restraint stress and/or administered LYC (10 mg/kg) for 21 days. The
effective model establishment was validated by open-field tests and
levels of corticosterone in serum. Histopathological staining observation
displayed that LYC could reduce chronic stress-induced spleen structure
damage. Furthermore, LYC treatment significantly reduced the number
of apoptotic-positive splenocytes caused by chronic stress via the
death receptor apoptotic pathway. We detected the interleukin 4 and
interferon γ levels in serum and spleen to determine the ratio
of Th1 and Th2 and found that LYC can alleviate the immunosuppression
induced by chronic stress. Notably, western blot and real-time polymerase
chain reaction indicated that LYC can reduce the expression of the
Notch-pathway-related proteins and mRNA in rats exposed to chronic
stress. Further study of the potential mechanisms by adding the Notch
pathway inhibitor DAPT revealed that LYC alleviates the structure
damage, apoptosis, and immunosuppression caused by chronic stress
via the suppression of the Notch pathway. Overall, this study presents
a strong rationale to target LYC as a treatment strategy to relieve
chronic stress-induced spleen injury.