Immune complex deposition is a critical factor in early renal damage associated with lupus nephritis (LN), and targeting plasma cell aggregation offers a promising therapeutic strategy. Ginsenoside compound K (i.e., 20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol) (CK), a derivative of ginsenoside, has indicated significant potential in alleviating renal damage in lupus-prone mice, potentially by modulating B cell dynamics in response to endoplasmic reticulum (ER) stress. In this study, CK (20 or 40 mg/kg) was orally administered to female MRL/lpr mice for 10 weeks. The effects of CK on B cell subpopulations, renal function, and histopathological changes were evaluated. Single-cell ribonucleic acid sequencing was employed to analyze gene expression profile and pseudotime trajectories during B cell-mediated renal injury. Additionally, in vitro B cell assays were conducted to explore the role of the sirtuin-1 (SIRT1)-X-box binding protein 1 (XBP1) axis in ER stress. Our findings demonstrated that CK effectively reduced anti-double stranded DNA (dsDNA) antibody levels, alleviated systemic inflammation, improved renal function, and facilitated the clearance of deposited immune complexes. CK likely suppressed the unfolded protein response (UPR), delaying the differentiation of renal-activated B cells into plasma cells. It promoted B cell-specific SIRT1 activation and inhibited the splicing of XBP1 into its active form, XBP1s. CK also restored ER morphology by interacting with calmodulin (CALM) to maintain ER calcium storage, reinforcing SIRT1 functional integrity and promoting XBP1 deacetylation, thereby limiting plasma cell differentiation. In conclusion, CK mitigates plasma cell accumulation in the renal microenvironment by preventing SIRT1-mediated XBP1 splicing, offering a potential therapeutic approach for LN.

OBJECTIVE： To optimize the processing technology of fried Radix Paeoniae， and to provide reference for quality control of the processed products. METHODS： The content of paeoniflorin in fried Radix Paeoniae was determined by HPLC. The determination was performed on Agilent ZORBAX SB-C18 column with mobile phase consisted of acetonitrile-0.05 mol/L potassium dihydrogen phosphate solution （15 ∶ 85， V/V） at the flow rate of 1.0 mL/min. The column temperature was 30 ℃， and detection wavelength was set at 230 nm. The sample size was 10 μL. The appearance character of fried Radix Peaoniae were investigated by appearance color， crosssection color， hardness and smell. Taking the comprehensive score of appearance character and paeoniflorin content as evaluation index， the dosage， stir-frying temperature and stir-frying time were investigated. According to the results of single factor test， Box-Behnken response surface methodology was used to optimize above 3 factors. The optimized processing technology was validated. RESULTS： The linear range of paeoniflorin were 0.02-4.15 mg/mL （r＝0.999 9）； precision， stablity， repeatability and sample recovery rate meet the requirements. The optimal technology of fried Radix Paeoniae included the dosage of 374.60 g， frying temperature of 101.61 ℃， frying time of 20 min. Under optimal technology， comprehensive score of fried Radix Paeoniae ranged 97.39-98.82 in 6 times of parallel verification tests （RSD＝0.54％）， which was close to predicted value 98.18. The color of fried Radix Paeoniae was slightly deeper than Radix Paeoniae， which was crisp and fragrant. CONCLUSIONS： The optimized processing technology of fried Radix Paeoniae is stable and feasible， and is suitable for the preparation of the processed products.