Combination therapy with doxorubicin and Berberis asiatica induces mitochondrial-mediated apoptosis and inhibits the PI3K/Akt pathway in non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is a well-defined malignancy of the lymphatic system, postulated to arise from the abnormal proliferation and accumulation of lymphocytes and their derivatives. Doxorubicin is a first-line chemotherapeutic drug used in several combination regimens; however, its dose-dependent toxicity and drug resistance remain serious threats to its efficacy. This study evaluated the combinatorial effects of doxorubicin with Berberis asiatica stem extract to overcome dose-dependent toxicity and enhance doxorubicin efficacy. B. asiatica stem extract was characterized by LC-HRMS to identify bioactive compounds. MTT assay and SynergyFinder analysis revealed that the interaction between doxorubicin and of B. asiatica stem extract is synergistic in mouse Dalton’s lymphoma (DL) and human Raji cell lines, with scores of 12.098 and 12.208, respectively. Combination therapy induced enhanced apoptosis, as evidenced by membrane blebbing, chromatin condensation, and an increased population of Annexin V/PI+ cells, along with elevated caspase 3/7 activity. The proportion of apoptotic cells following treatment of DOX and BSE was 33.50% in DL cells and 36.66% in Raji cells. Combined treatment had significant effects on reactive oxygen species (ROS) production, loss of mitochondrial membrane potential, increased perinuclear mitochondrial clustering, and cell cycle arrest at the G2/M phase compared to monotherapy. Protein analysis revealed downregulation of anti-apoptotic Bcl-2, upregulation of pro-apoptotic Bax, caspase 3 and cleaved caspase 3, and attenuation of the PI3K/Akt pathway via decreased PDK-1 and p-Akt expression in the combination therapy group. Combined treatment in DL-bearing BALB/c mice significantly improved survival, reduced tumor burden, and restored the tissue architecture. The present study demonstrates that B. asiatica stem extract acts as an effective chemosensitizer, enhancing doxorubicin efficacy through mitochondrial-mediated apoptosis and PI3K/Akt pathway attenuation, offering a promising combinatorial approach for NHL therapy.