酒精性肝纤维化大鼠模型的建立及Smad7/TGF-β表达变化

Mechanisms for Zhige oral solution to prevent and treat alcoholic liver disease in rats

AIM

To explore the preventive and therapeutic effects of Zhige oral solution on alcoholic liver disease in rats and the underlying mechanisms.

METHODS

Ninety male SD rats were randomly divided into six groups: a normal group, a model group, a positive control group, and three intervention groups. The normal group was only given distilled water at 1.0 mL per 100 g/d by gavage, and the other groups were given 52% Luzhou Laobaigan 1.0 mL per 100 g/d by gavage. In addition, the intervention groups were also given different doses (low, medium, and high) of Zhige oral solution and the positive control group was given Jiejiuling oral solution. All groups were allowed free access to water, and fed a normal diet. All the rats were killed at the end of the 12^th week. Hematoxylin and eosin (HE) staining was used to observe the structural changes of liver tissue. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TG), and total cholesterol (TC) were measured with an automatic biochemical analyzer. Serum levels of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) were detected by enzyme-linked immunosorbent assay (ELISA). The contents of TC and TG in the liver were measured by colorimetric assay. The protein expression of cytochrome P450 2E1 (CYP450 2E1) in the liver was detected by Western blot.

RESULTS

Compared with the normal group, the liver index and the levels of ALT, AST, TC, TG, ADH, ALDH, and CYP450 2E1 were significantly altered in all groups except the high-dose group (P < 0.01 or 0.05), with the model group and low-dose group exhibiting the most significant changes (P < 0.01). Varying degrees of fat vacuolation can be seen in the liver in all groups. Compared with the model group, all the tested indicators above showed varying degrees of reversal in the positive control group and the three intervention groups (P < 0.01 or 0.05), and the reverse effect was best in the high-dose group (P < 0.01). The therapeutic effect of the medium-dose group was similar to that of the positive control group (P > 0.05).

CONCLUSION

The anti-alcoholic and liver-protective effects of Zhige oral solution may be related to reversing the activities of ADH, ALDH, and other enzymes, inhibiting free radicals and acetaldehyde production, reducing oxidative stress, and improving lipid metabolism disorder in rats.

Expression of cytokines in rats with ethanol-induced liver injury treated with Zhige oral solution

AIM

To investigate the correlation between expression of cytokines and preventive effects of Zhige oral solution against alcoholic liver injury (ALI) in rats.

METHODS

Rats were divided into six groups: normal control group, model group, positive control group, high-, medium-, and low-dose Zhige oral solution groups. Except the normal control group, ALI was induced in rats of other groups by simple alcohol gavage. The high-, medium-, and low-dose Zhige oral solution groups were given high-, medium- and low-dose group Zhige oral solution, the positive control group was given Jiejiuling oral solution, and the normal control group was given distilled water. Twelve weeks later, abdominal aorta arterial blood was collected to measure serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), as well as the contents of serum tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-10. The rats were sacrificed to observe the pathological changes in liver tissue.

RESULTS

Compared with the normal control group, serum levels of TNF-α, IL-6, IL-10, ALT, and AST were significantly altered in all groups except the high-dose Zhige oral solution group (P < 0.01 or 0.05), and varying degrees of massive swelling of liver cells and red lipid droplets were observed in liver tissues in all groups. Compared with the model group, all the tested indicators showed varying degrees of reversal in the positive control group and three intervention groups (P < 0.01 or 0.05), and the reversal effect was best in the high-dose Zhige oral solution group (P < 0.01). The therapeutic effect in the middle dose group was similar to that in the positive control group (P > 0.05).

CONCLUSION

Zhige oral solution can reduce or inhibit the occurrence of ALI by regulating the levels of cytokines in rats.

Resveratrol Ameliorates Experimental Alcoholic Liver Disease by Modulating Oxidative Stress

The aim of this study was to investigate the hepatoprotective effects of resveratrol in alcoholic liver disease (ALD). Alcohol was administered to healthy female rats starting from 6% (v/v) and gradually increased to 20% (v/v) by the fifth week. After 16 weeks of intervention, liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) were analyzed using a chemistry analyzer, while hepatic antioxidant enzymes, oxidative stress markers, and caspase 3 activity were assessed using ELISA kits. Furthermore, hepatic CYP2E1 protein levels and mRNA levels of antioxidant and inflammation-related genes were determined using western blotting and RT-PCR, respectively. The results showed that resveratrol significantly attenuated alcohol-induced elevation of liver enzymes and improved hepatic antioxidant enzymes. Resveratrol also attenuated alcohol-induced CYP2E1 increase, oxidative stress, and apoptosis (caspase 3 activity). Moreover, genes associated with oxidative stress and inflammation were regulated by resveratrol supplementation. Taken together, the results suggested that resveratrol alleviated ALD through regulation of oxidative stress, apoptosis, and inflammation, which was mediated at the transcriptional level. The data suggests that resveratrol is a promising natural therapeutic agent against chronic ALD.