• Modeling Mechanism：

  Aristolochic acid A (AAI) accumulates in proximal tubular epithelial cells (PTEC) via organic anion transporters (OATs); it is metabolized to produce aristolochic acid-nitrosamine ions, forming AA-DNA adducts, which can lead to gene mutations and cancer risk; it directly binds to and inhibits key enzymes in the tricarboxylic acid cycle, glycolysis, and mitochondrial respiration (IDH2, MDH2, PKM, ATP synthase, etc.), resulting in mitochondrial dysfunction and energy depletion; it activates oxidative stress, endoplasmic reticulum stress, and apoptosis pathways, accompanied by a reduction in peritubular capillaries and hypoxia, ultimately leading to renal tubular atrophy and renal interstitial fibrosis.

• Related Products：

  Aristolochic acid A (T2801)

• Modeling Method：

  Experimental Subject：

  Mice: 129/SvEv background (wild-type/WT, TNF PTKO, TNF DNKO); male; 8–12 weeks of age

  Dosage and Administration Route：

  ① Acute model: 5 mg/kg Aristolochic acid A, dissolved in physiological saline, intraperitoneal injection (i.p.), administered consecutively for 3 days, with tissue collection on day 4;
  ② Chronic model: 4 mg/kg Aristolochic acid A, intraperitoneal injection, every other day for 6 doses, tissue collection 5 weeks after final administration;
  ③ Intervention group (optional): 2.2 mg/kg pifithrin-α, Intraperitoneal injection, Single dose on day 1 for acute model, weekly for 3 doses in chronic model;
  Control treatment: equal-volume physiological saline administered intraperitoneally; all other procedures identical.

  Dosing Frequency and Duration Model：

  Acute model (Aristolochic acid A): Once daily for 3 consecutive days;
  Chronic model (Aristolochic acid A): Administered every other day for a total of 6 doses;
  Intervention group (pifithrin-α): Single administration in acute model (synchronised with acute model Day 1); weekly administration in chronic model, cumulative total of 3 doses;
  Control group: Administered at the same frequency as the corresponding model group

• Validation：

  1. Functional Indicators: - Acute Model: Elevated serum blood urea nitrogen (BUN), upregulated NGAL (Lcn2) mRNA expression in renal tissue (p<0.05); - Chronic Model: Significantly elevated BUN (WT group 97±9 mg/dl vs TNF PTKO group 70±7 mg/dl, p<0.05), decreased creatinine clearance; 2. Molecular Indicators: - Inflammation and fibrosis: Upregulated expression of IL-1β, TGF-β1, Col1a1, FN1 mRNA and Col-I protein in renal tissue, significantly decreased in the TNF PTKO group (p<0.05); - Cell Cycle: Flow cytometry showed an increased proportion of PTEC cells in G2/M phase and a decreased proportion in G0/G1 phase; pifithrin-α could reverse this phenotype; - Regulatory Cell Death: Bax, Bcl2, p53, and RIP3 levels in renal tissue of the chronic model. Protein expression was upregulated (p<0.05); 3. Pathological indicators: - Acute model: PAS staining showed renal tubular necrosis, lumen dilation, and epithelial swelling (damage score of WT group was significantly higher than that of TNF PTKO group, p<0.05); - Chronic model: increased area of renal interstitial fibrosis, and significantly reduced degree of fibrosis in TNF PTKO group.

*Precautions：

*References：Wen Y,et,al. TNF- α from the Proximal Nephron Exacerbates Aristolochic Acid Nephropathy. Kidney360. 2024 Jan 1;5(1):44-56.