Comprehensive safety assessment of Qiwei Tiexie Pill: integrating histopathological, biochemical, and metabolomic analyses in a rat model

Qi Zheng¹Wenya Liu¹Cong Wang¹Zhaoben Kan²Qian Wang²Lu Cui²Zhaoxiang Lin³Feng Zhou⁴Xin Feng^2*Junsong Wang^1*

• ¹Nanjing University of Science and Technology, Nanjing, China
• ²China Tibetology Research Center, Beijing, China
• ³South-Central University for Nationalities, Wuhan, Hubei Province, China
• ⁴Technological Innovation Center of Traditional Tibetan Medicine Modernization of XiZang Autonomous Region, Lhasa, China

This study presents a comprehensive evaluation of the acute toxicological mechanisms of Qiwei Tiexie Pill (QWTX) and its key mineral component, processed iron powder, using an integrative approach combining histopathological examination, serum biochemistry, and multi-platform metabolomics (¹H NMR and LC-MS) in Sprague-Dawley rats following 7-day oral administration. While both treatments preserved hepatic structural integrity and did not induce hepatotoxicity, significant renal effects were observed in a dose- and formulation-dependent manner. High-dose processed iron powder caused moderate renal histopathological alterations—primarily vascular changes and hemorrhage—alongside metabolic disruptions in both liver and kidney. In contrast, QWTX, despite inducing significant metabolic perturbations at high dose, maintained normal renal architecture, indicating a protective effect conferred by its herbal components. Metabolomic and biochemical analyses revealed that both agents induce systemic metabolic reprogramming across four interdependent physiological domains: (1) energy metabolism, characterized by TCA cycle impairment and enhanced branched-chain amino acid (BCAA) catabolism; (2) oxidative stress, with evidence of glutathione depletion, pentose phosphate pathway suppression, and lipid peroxidation; (3) nitrogen metabolism, showing a "hepato-renal disconnect" between upregulated hepatic urea synthesis and impaired renal urea handling, leading to functional nitrogen retention; and (4) neuroendocrine regulation, with widespread dysregulation of catecholamine, serotonin, melatonin, steroid, and sex hormone pathways. These interconnected disturbances suggest that toxicity arises not from isolated organ damage but from network-level metabolic failure. Notably, QWTX demonstrated a superior safety profile compared to processed iron powder alone, particularly in preserving renal structure and mitigating iron-associated nephrotoxicity. However, high-dose QWTX still triggered significant oxidative and metabolic stress, underscoring the importance of dose optimization in clinical use. These findings provide a systems-level understanding of the acute toxicological profile of QWTX and processed iron powder, supporting the traditional principles of herbal-metal synergy in Tibetan medicine while highlighting the need for long-term safety studies to evaluate cumulative mineral exposure and chronic metabolic effects.