Effects of different transdermal penetration enhancers applied to herbal cake-partitioned moxibustion on liver lipids, HSL and HMG-CoA reductase in hyperlipidemia rabbits

Abstract

To observe the effects of laurocapram and borneol as transdermal penetration enhancers applied to herbal cake-partitioned moxibustion on liver lipids, hormone-sensitive lipase (HSL) and hydroxymethylglutaryl CoA (HMG-CoA) reductase in hyperlipidemia rabbits. Forty New-Zealand rabbits were randomly divided into 5 groups using the random number table method, with 8 rats in each group. Rabbits in the blank group were fed routinely with a normal diet; rabbits in the other groups were fed with high-fat diet for 12 weeks to establish the hyperlipidemia model. Rabbits in the blank and the model groups were not given any intervention. After the model was prepared successfully, rabbits in the non-transdermal penetration enhancer group received herbal cake-partitioned moxibustion without transdermal penetration enhancers; rabbits in the laurocapram group and the borneol group received herbal cake-partitioned moxibustion with laurocapram or borneol respectively. After 4 weeks of treatment, the serum was isolated and enzyme-linked immunosorbent assay (ELISA) was applied for the detection of HSL and HMG-CoA reductase. The liver tissues were isolated, and total cholesterol (TC) and triglycerides (TG) were measured by enzymatic methods. One-step method was applied for high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) detection, and transmission turbidimetry was for apolipoprotein A1 (Apo-A1) and apolipoprotein B (Apo-B) detection. The serum concentrations of the drugs in the laurocapram and the borneol groups were significantly higher than those in the non-transdermal penetration enhancer group (both P<0.05); all drug penetrations in the borneol group were significantly higher than those in the laurocapram group (both P<0.05), except for tanshinone IIA. Compared with the non-transdermal penetration enhancer group, the HSL was significantly increased while the HMG-CoA reductase was significantly decreased in the laurocapram and the borneol groups (both P<0.05); between groups, the HSL in the borneol group was significantly higher than that in the laurocapram group (P<0.05). Compared with the blank group, the levels of LDL-C, TG, TC and Apo-B in rabbit liver were significantly increased in the model group (P<0.05); compared with the model group, the levels of LDL-C, TG, TC and Apo-B in the non-transdermal penetration enhancer, the laurocapram, and the borneol groups were significantly decreased (all P<0.05); between groups, the TG and TC in the laurocapram group and the LDL-C, TG, TC and Apo-B in the borneol group were significantly lower than those in the non-transdermal penetration enhancer group (all P<0.05), and the TG, LDL-C and Apo-B in the borneol group were significantly lower than those in the laurocapram group (all P<0.05). Compared with the blank group, the HDL-C and Apo-A1 were significantly decreased in the model group (both P<0.05), while compared with the model group, the HDL-C and Apo-A1 were significantly increased in the non-transdermal penetration enhancer, the laurocapram, and the borneol groups (all P<0.05). Between groups, the Apo-A1 in the laurocapram group, the HDL-C and Apo-A1 in the borneol group were significantly higher than those in the non-transdermal penetration enhancer group (all P<0.05). The application of laurocapram and borneol, as transdermal penetration enhancers, in herbal cake-partitioned moxibustion can promote the penetration of the drugs in the herbal cake, increase the levels of HDL-C and Apo-A1, improve the metabolism of HSL and HMG-CoA reductase, and also simultaneously reduce the levels of TC, TG, LDL-C and Apo-B in the liver. The transdermal penetration enhancement effect of borneol is slightly better than or equivalent to that of laurocapram.