Research on the mechanism of Sini Powder regulating the HPA axis and inflammatory levels to ameliorate depression-like behaviors and inhibiting tumor proliferation in liver cancer

To investigate the effects of Sini Powder on serum hypothalamic-pituitary-adrenal (HPA) axis-related hormones and inflammatory factors in liver cancer mice with comorbid depression, and to evaluate its effect on depressive behavior and tumor proliferation activity.

Forty-eight specific pathogen-free female C57BL/6 mice were randomly assigned to either a blank (n = 8) or model group (n = 40). The modeling group was subjected to chronic unpredictable mild stress (CUMS) for six weeks. Both groups underwent orthotopically transplanted liver tumor surgery at the end of the fourth week of CUMS treatment. At the end of the sixth week of CUMS treatment, color Doppler ultrasonography was used to observe tumor formation in the orthotopic transplantation liver tumors, and the tail suspension test was used to assess depressive behavior. Non-tumor-bearing and deceased mice were excluded. The remaining model group mice were stratified by tail suspension immobility time and randomly assigned to the following groups: model group (distilled water), Fluoxetine group (5.0 mg/kg), and Sini Powder low-dose, medium-dose, and high-dose groups (5.2, 10.4, and 20.8 g/kg, respectively), with six mice per group. The treatments were administered once daily for 21 consecutive days. After treatment, depressive behaviors were assessed using the open field, tail suspension, and forced swimming tests. The proliferation status of the orthotopic liver transplantation tumor was evaluated by measuring the size of the tumor, observing pathological changes in the tumor tissue through hematoxylin and eosin staining, and detecting the positive cell rate of proliferating cell nuclear antigen (Ki-67) in the tumor tissue using immunohistochemistry. The levels of HPA axis-related hormones in serum, such as corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), corticosterone (CORT), as well as inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were measured using an enzyme-linked immunosorbent assay. Western blotting was used to assess mitogen-activated protein kinase (MAPKs) phosphorylation and the expression of nuclear factor-κB (NF-κB), NOD-like receptor family pyrin domain-containing receptor 3 (NLRP3), and cysteine aspartic protease-1 (Caspase-1) in orthotopic tumors.

Compared with the blank group, the model group showed reduced total distance traveled in open field test, prolonged immobility times in the tail suspension and forced swimming tests (P＜0.05, P＜0.01), indicating successful establishment of the liver cancer with comorbid depression mice model. Also, the model group showed increased orthotopic tumor volume (P＜0.01), and elevated serum CRH, ACTH, CORT, TNF-α, IL-1β, and IL-6 levels (P＜0.01). The phosphorylation of MAPKs in tumor tissues was suppressed (P＜0.01), while NF-κB, NLRP3, and Caspase-1 expression levels were downregulated (P＜0.01). Compared with the model group, Sini Powder medium-and high-dose groups exhibited increased total distance traveled in the open field test (P＜0.05), reduced forced swimming test and prolonged total distance traveled in open field test (P＜0.01), while Sini Powder high-dose group showed reduced immobility times in the tail suspension test (P＜0.05). Also, Sini Powder low-dose, medium-dose, and high-dose groups showed slower tumor growth, histological changes, including vacuolization and necrosis, decreased Ki-67 positive cell rate (P＜0.01), and reduced serum CRH, ACTH, CORT, TNF-α, IL-1β, and IL-6 levels (P＜0.05).Additionally, the phosphorylation of MAPKs in tumor tissues was suppressed (P＜0.01), and NF-κB, NLRP3, and caspase-1 expression levels were downregulated (P＜0.01).

Sini Powder may alleviate depressive behaviors and suppress tumor proliferation activity in liver cancer mice with comorbid depression by modulating MAPKs activation, inhibiting NF-κB, NLRP3, and Caspase-1 expressions, and reducing serum inflammatory factors and HPA axis-related hormones levels.