Objective To investigate the effects of different doses of Yiyi Ren aqueous preparation on blood lipid regulation and spleen-strengthening and dampness-eliminating effects in hyperlipidemia rats with syndrome of spleen deficiency and excessive dampness.

Methods Sixty SD male rats were randomly divided into blank control group, model group, low-dose, medium-dose, high-dose Yiyi Ren aqueous preparation groups, and positive drug control group, with 10 rats in each group. A hyperlipidemia rat model with syndrome of spleen deficiency and excessive dampness was established by feeding with a high-fat diet for 21 consecutive days combined with a damp bedding environment. After drug administration, behavioral tests such as grip strength, weighted swimming test, and open field test were conducted; changes in body weight in each group were observed; serum levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were detected; levels of vasoactive intestinal peptide (VIP), antidiuretic hormone (ADH), and aldosterone (ALD) were measured by enzyme-linked immunosorbent assay (ELISA).

Results Compared with the blank control group, the model group showed decreased HDL-C, grip strength, exhaustive swimming time, and total distance, as well as increased TC, TG, LDL-C, ADH, ALD, and VIP (P < 0.05). Compared with the model group, TC, TG, and LDL-C levels were decreased in the medium-dose, high-dose Yiyi Ren aqueous preparation groups, and the positive drug control group, while the HDL-C levels were increased in the low-dose, medium-dose, and high-dose Yiyi Ren aqueous preparation groups and the positive drug control group (P < 0.05). Compared with the model group, the high-dose Yiyi Ren aqueous preparation group showed increased grip strength, exhaustive swimming time and total distance and decreased serum ADH levels (P < 0.05). Compared with the model group, the medium and high-dose Yiyi Ren aqueous preparation groups showed decreased serum ALD and VIP levels (P < 0.05).

Conclusion Yiyi Ren aqueous preparation has an effect on regulating blood lipid levels in hyperlipidemia rats with syndrome of spleen deficiency and excessive dampness, and it can alleviate physical fatigue, improve abnormal exploratory behavior, and maintain normal water metabolism and motor function in rats.