Zhaohui Xu

Background: Endometriosis is an estrogen-dependent disorder with limited treatment options. The precise molecular targets of curcumin and its effects on local estrogen synthesis in this disease remain unclear. Methods: We investigated curcumin’s efficacy and mechanism via network pharmacology, in vitro functional assays in ectopic endometrial cells, an allogeneic mouse model, and target validation through molecular docking, thermal shift, and hydrolysis stability assays. Results: Curcumin significantly inhibited ectopic cell malignant phenotypes, reducing migration distance by 55.60 ± 7.32%, 80.34 ± 11.19%, and 82.88 ± 13.67% at 5, 10, and 15 μM, respectively, and decreasing invasive cell numbers by 40.38 ± 7.67%, 58.33 ± 12.70%, and 60.18 ± 9.07%, respectively (all p < 0.05). In a mouse model, curcumin (200 mg/kg/day) reduced lesion number by 38.46% (2.167 ± 0.752 vs. 1.333 ± 0.516, p = 0.0493) and lesion volume by 59.73% (0.0497 ± 0.0173 vs. 0.0200 ± 0.0130 mm³, p = 0.00732). It also suppressed de novo estrogen synthesis and modulated the estrogen receptor α (ERα) and β (ERβ) ratio. Mechanistically, curcumin directly bound to and inhibited protein kinase A (PKA), a key kinase in the cAMP signaling pathway. Conclusions: We first demonstrate that curcumin alleviates endometriosis by targeting PKA to inhibit local estrogen synthesis, identifying PKA as a novel therapeutic target and curcumin as a promising treatment candidate.

Introduction: The total lignans from Fructus arctii (TLFA) is a mixture of a series of lignans isolated from dried ripe fruit of Arctium lappa L. We previously reported on the pharmacological activity of TLFA that is related to diabetes. An accurate and practical TLFA quantitative analysis method for utilising it needs to be established.Objective: This study aimed to develop an effective quantitative analysis method for assessing the TLFA quality.Methods: A total of 11 marker components were confirmed by analysing the high‐performance liquid chromatography fingerprints of 24 batches of TLFA samples. The samples were prepared from TLFA and structurally identified as lappaol H, lappaol C, arctiin, arctignan D, arctignan E, matairesinol, arctignan G, isolappaol A, lappaol A, arctigenin, and lappaol F. In the quantitative analysis of multi‐components by the single‐marker (QAMS) method and with arctiin as an internal reference substance, the content of these lignans in TLFA was simultaneously determined according to their relative correction factors with arctiin.Results: There was no significant difference between results measured by the QAMS and traditional external standard methods. Hierarchical cluster and principal component analyses were performed to evaluate 24 TLFA batches based on the contents of 10 marker components. The results revealed that QAMS method combined with chemometric analyses could accurately measure and clearly distinguish the different quality samples of TLFA.Conclusion: The QAMS method is a reliable and promising quality control method for TLFA. It can provide a reference for promoting quality control of complex multi‐component systems, especially for traditional Chinese medicine.

Fructus Arctii (great burdock achene) is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is included in the Chinese pharmacopoeia. It has been reported that the clinical use of Fructus Arctii resulted in a satisfactory hypoglycemic effect in diabetic patients. This study aimed to investigate antidiabetic activity and mechanism of total lignans from Fructus Arctii (TLFA) in KKAy mice, a spontaneous Type 2 diabetic rodent model that exhibits marked obesity. In this study, KKAy mice were gavaged once daily with solvents (0.5% sodium carboxymethyl cellulose), TLFA (250 and 125 mg/kg), or metformin (200 mg/kg) for 11 weeks, and C57BL/6J mice treated with saline solution (0.9%, w/v) were used as normal control. The results indicate that TLFA has dual effects of hypoglycemia and weight loss, and administration of TLFA in KKAy mice could decrease fasting blood glucose, glycated hemoglobin, and body weight; improve oral glucose tolerance; increase high density lipoprotein cholesterol; and decrease triglycerides and free fatty acid in mice serum. Its efficacy may associate with multiple mechanisms of action such as stimulation of insulin secretion, activation of phosphatidylinositol 3‐kinase/protein kinase B, and adenosine‐monophosphate‐activated protein kinase signaling pathway, decreasing leptin.

The antidiabetic activity of the total lignan from the plant Fructus Arctii, used in China for the control of diabetes, was investigated in models of alloxan‐induced diabetic mice and hyperglycemic‐hyperlipidemic diabetic rats. The biochemical parameters studied were: blood glucose, glucose tolerance, serum insulin, serum triglycerides, total cholesterol and high density lipoprotein (HDL). Total lignan was given to mice and rats daily for 10 days at doses of 2.0, 1.0, 0.5 g/kg and 1.38, 0.69, 0.35 g/kg respectively. The alloxan‐diabetic animals showed significant reductions in plasma glucose, triglycerides and total cholesterol after treatment with the total lignan from the plant Fructus Arctii and glibenclamide (used as standard) compared with the diabetic controls, while the glucose tolerance, serum insulin level and HDL‐cholesterol were elevated without the risk of hypoglycemia. In conclusion, the total lignan from the plant Fructus Arctii has been proven to be a safer antidiabetic agent and might help to prevent diabetic complications. It can serve as a good adjuvant in the present armamentarium of antidiabetic drugs. Copyright © 2007 John Wiley & Sons, Ltd.