Cardiac Modulation by Santolina chamaecyparissus Aqueous Extract in a Rat Model of Mammary Carcinogenesis

Cardiotoxicity remains a major concern in breast cancer management, with implications for prognosis and quality of life. Natural compounds have shown chemopreventive potential while preserving cardiac safety. This study evaluated the cardiac effects of a Santolina chamaecyparissus aqueous extract (SCE), characterized by high levels of 1,3-O-dicaffeoylquinic acid and myricetin-O-glucuronide, in female Wistar rats subjected to N-methyl-N-nitrosourea (MNU)-induced mammary carcinogenesis.

Twenty-eight animals were assigned to four groups (n = 7/group): control (CTRL), MNU-induced (IND), SCE-supplemented (SCE), and MNU-induced SCE-supplemented (SCE+IND). SCE was administered in water (120 µg/mL) for 20 weeks, and MNU was injected intraperitoneally (50 mg/kg) at 50 days of age. At the end of the experiment, body and heart weights were recorded, creatine kinase MB (CK-MB) concentrations assessed, and echocardiography performed to evaluate cardiac structure and function.

Final body and relative heart weights did not differ among groups. CK-MB was lower in SCE-supplemented groups compared with CTRL and IND (p < 0.05). IND animals exhibited a hyperdynamic functional profile accompanied by impaired ventricular filling, which was attenuated in SCE+IND animals (p < 0.05). Cardiac structural parameters were largely preserved with SCE, despite an increased left ventricular mass (p < 0.05).

SCE did not induce adverse cardiac effects and partially mitigated early carcinogenesis-associated cardiac alterations under the tested conditions, supporting its cardiac safety as a potential phenolic-rich chemopreventive strategy.