[Study on mechanism of ultrafiltration membrane extract of Angelicae Sinensis Radix and Hedysari Radix regulates mitochondrial function to ameliorate diabetic kidney disease].

This study aims to investigate the action mechanism and target molecules of the ultrafiltration membrane extract of Angelicae Sinensis Radix and Hedysari Radix in improving renal tissue injury in rats with diabetic kidney disease(DKD) from the perspective of mitochondrial function. Ten SPF-grade male Wistar rats were selected as the control group, while 40 rats were fed a high-fat and high-sugar diet for four weeks followed by a single intraperitoneal injection of streptozotocin(STZ) 35 mg·kg~(-1) to establish the DKD model. The successfully modeled rats were then randomly divided into four groups: the model group, the canagliflozin group, the Angelicae Sinensis Radix and Hedysari Radix aqueous decoction group, and the ultrafiltration membrane extract of Angelicae Sinensis Radix and Hedysari Radix group, with ten rats per group. All groups were administered via gavage for eight weeks. Renal function was assessed through 24 h urinary total protein(24-UTP) and biochemical parameters. HE staining, TUNEL staining, and transmission electron microscope were used to observe pathological morphological changes, apoptosis, and the status of intracellular organelles in cells. ELISA and Western blot were employed to measure adenosine triphosphate(ATP) content and the expression of mitochondrial function-related proteins, including optic atrophy 1(OPA1), mitofusin 2(Mfn2), dynamin-related protein 1(Drp1), ubiquitin-binding protein P62(P62), B-cell lymphoma/leukemia-2(Bcl-2), Bcl-2 interacting protein1(Beclin-1), and Bcl-2-associated X protein(Bax) in renal tissue. The results show that, compared to those in the control group, the rats in the model group exhibit a significant decrease in body weight(P<0.01), along with elevated levels of blood glucose, 24-UTP, blood urea nitrogen(BUN), and serum creatinine(Scr)(P<0.01). Renal tubular dilation, vacuolar changes in renal tissue cells, and a significant increase in apoptosis rate(P<0.01) are observed, accompanied by mitochondrial swelling, cristae disappearance, and rupture. ATP levels in renal tissue are significantly reduced(P<0.01), while the protein expressions of OPA1, Mfn2, Drp1, Beclin-1, and Bax are significantly increased(P<0.05, P<0.01). The expression levels of P62 and Bcl-2 are significantly decreased(P<0.01). Compared to those in the model group, the rats in the ultrafiltration membrane extract group show an upward trend in body weight, with reductions in 24-UTP, BUN, and Scr levels(P<0.01). Renal tubular dilation and glomerular cell vacuolation are alleviated, and the apoptosis rate of renal tissue cells is significantly reduced(P<0.01). Mitochondria exhibit mild swelling but remain largely intact. ATP levels in renal tissue are significantly increased(P<0.01), while the expressions of OPA1, Mfn2, Drp1, Beclin-1, and Bax are significantly decreased(P<0.01). The expression of Bcl-2 is significantly increased(P<0.01). In conclusion, ultrafiltration membrane extract of Angelicae Sinensis Radix and Hedysari Radix may attenuate renal tissue injury and delay disease progression in DKD rats by restoring mitochondrial dynamics, controlling mitochondrial fission-fusion balance, and improving mitochondrial function.