Phenolic-rich fraction of green tea attenuates histamine-mediated cardiopulmonary toxicity by inhibiting Cox-2/NF-κB signaling pathway and regulating oxidant/antioxidant balance

Background Histamine (HIS) has a substantial impact on the development of numerous allergic disorders including asthma. Antihistamines mostly target histamine receptor-1 alone, so it is not entirely effective in the treatment of allergic diseases. In the current investigation, we examine the growing evidence for novel therapeutic strategies that aim to treat histamine-mediated cardiopulmonary toxicity with the phenolic-rich fraction of green tea (PRFGT). Results Our findings demonstrated that weekly ingestion of HIS to rats induced oxidant/antioxidant imbalance in both lung and heart homogenates. The histopathological examination demonstrated extensive interstitial pneumonia with progressive alveolar and bronchial damage in HIS receiving groups. Heart sections showed severe myocardial necrosis and hemorrhage. All lesions were confirmed by the immunohistochemical staining that demonstrated strong caspase-3, cyclooxygenase-2 (Cox-2), and tumor necrosis factor-α (TNF-α) protein expressions along with upregulation of the pulmonary m-RNA expression of TNF-α, nuclear factor kappa-B (NF-κB), and interleukin-1β (IL-1β) genes and cardiac levels of many apoptotic genes. Otherwise, the pretreatment of rats with PRFGT had the ability to alleviate all the aforementioned toxicological parameters and return the microscopic picture of both lung and heart sections to normal histology. Conclusions We concluded that PRFGT’s powerful antioxidant, anti-inflammatory, and anti-apoptotic properties can reduce cardiopulmonary toxicity caused by HIS. We recommended daily intake of green tea as a beverage or adding it to foods containing elevated levels of HIS to prevent its possible toxicity.