Evaluation of the impact of Polygonum capitatum, a traditional Chinese herbal medicine, on rat hepatic cytochrome P450 enzymes by using a cocktail of probe drugs

Potential risks associated with traditional herbal medicine use in cancer care: A study of Middle Eastern oncology health care professionals

“…A total of 29 of the 44 herbal products identified were associated with safety‐related concerns (65.9%) (Table ) . These were grouped according to 3 predominant themes: 1) potentially harmful herb‐drug interactions with a reduction in bioavailability (and thus efficacy) of anticancer agents, or increased drug levels with increased toxicity (15 herbs; 34.1%); 2) directly toxic effects of herbal compounds and metabolites (18 herbs; 40.9%); and 3) enhanced anticancer effects of conventional treatment through either synergy with herbal components or chemosensitization of cancer cells, thereby increasing the response to treatment (7 herbs; 15.9%).…”

“…These were mediated primarily through the cytochrome P450 enzymes, primarily induction of CYP3A4 . CYP induction can cause a reduction in bioavailability and subsequently the effectiveness of anticancer agents, whereas enzyme inhibition can increase the risk of toxicity, such as that observed with etoposide, paclitaxel, vinblastine, and vincristine . Additional effects on factors such as intestinal P‐glycoprotein, which inhibits drug absorption, can alter the bioavailability of anticancer drugs such as etoposide .…”

“…37,38 CYP induction can cause a reduction in bioavailability and subsequently the effectiveness of anticancer agents, [39][40][41] whereas enzyme inhibition can increase the risk of toxicity, such as that observed with etoposide, paclitaxel, vinblastine, and vincristine. [42][43][44][45][46][47] Additional effects on factors such as intestinal P-glycoprotein, which inhibits drug absorption, can alter the bioavailabil-ity of anticancer drugs such as etoposide. [48][49][50] The inhibition of boronic acid-based proteasome inhibitors (eg, bortezomib) 51 or the transport of irinotecan and its metabolite, SN-38, can increase biliary removal with an increase in the half-life of the drug 52 ; a reduction in organic anion transporting polypeptides can increase the absorption of chemotherapy agents such as etoposide, irinotecan, methotrexate, and paclitaxel 53 ; gingko biloba can inhibit paclitaxel metabolism (in vitro) 54 ; and an increase in the bioavailability or a decrease in the activity of tamoxifen in estrogen-responsive tumors may occur, [55][56][57][58] as well as a reduction in the drug's active metabolite levels via CYP2D6 inhibition.…”

Evaluation of the inhibition potential of plumbagin against cytochrome P450 using LC-MS/MS and cocktail approach

“…Meanwhile, the medicinal plant is the main ingredient of Qubai Babuqi Pian (Sinopharm XinJiang Pharmaceutical Co., Ltd.) which is used to treat leucoderma in Uighur medicine. Nowadays, herbal medicines, especially being consumed along with modern drugs, are increasingly popular when patients are in several diseases or conditions1114. When they are co-administered over overlapping time periods, the possibility of HDIs mediated by CYPs might exist2021.…”

“…However, the inhibition effects of plumbagin on CYP activities were rarely concerned. Among all CYP isoforms in humans, CYP3A4, CYP2C9, CYP1A2, CYP2E1, CYP2D6 and CYP2B6 are relative abundant, which accounts about for 40%, 20%, 13%, 10%, 2% and 2% in total CYPs respectively, and responsible for metabolism of the majority of clinically prescribed drugs14222324. CYP1A2 is involved in the metabolism of a variety of clinically using drugs, such as clozapine, tacrine, tizanidine, theophylline, and several important endogenous compounds22242526.…”