Preparation of anti-mouse caspase-12 mRNA hammerhead ribozyme and identification of its activity in vitro

Hammerhead ribozymes in therapeutic target discovery and validation

Gene function assessment is a main task in biological networking investigations and system biology. High throughput technologies provide an impressive body of data that enables the design of hypotheses linking genes to phenotypes. When a putative scenario is depicted, gene knockdown technologies and RNA-dependent gene silencing are the most frequent approaches to assess the role of key effectors. In this paper, we discuss the relevance of hammerhead ribozymes in target discovery and validation, describing their properties and applications and highlighting their selectivity. In particular, similarities with siRNAs are presented and advantages and drawbacks are discussed. A description of the perspectives of ribozyme application in wide range studies is also provided, strengthening the value of these inhibitors for target validation purposes.

Effects of betaine on expression of caspase-12 in ethanol-induced liver injury in rats

AIM: To investigate the effects of betaine on the expression of caspase-12 in the liver of rats with ethanol-induced liver injury.

METHODS: Forty-eight female SD rats were randomly divided into 4 groups: control, model, and low and high dose betaine group. Except the rats in control group, all the rats were fed fat-rich diet plus ethanol plus fish oil gavage for 8 wk. Betaine was administered intragastrically in the rats of betaine groups after 4-wk exposure of ethanol. The expression of caspase-12 was detected in the liver tissues by immunohistomistry and semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS: Compared with that in control group, the expression of caspase-12 was markedly induced in the liver after chronic ethanol consumption (mRNA: 1.00 vs 0.18, P <0.01; protein: 0.296 9±0.045 1 vs 0.052 6±0.023 4, P < 0.01). However, the level of caspa-se-12 expression was significantly lower in high- and low-dose betaine group than that in model group (mRNA: 0.10, 0.12 vs 1.00, P < 0.01; protein: 0.121 5±0.013 0, 0.185 0±0.008 5 vs 0.296 9±0.045 1, P < 0.01). Significant difference of caspase-12 expression also existed between high- and low-dose betaine group (mRNA: 0.10 vs 0.12, P < 0.05; protein: 0.121 5±0.013 0 vs 0.185 0±0.008 5, P < 0.05).

CONCLUSION: Betaine suppresses the expression of caspase-12 both in mRNA and protein level in the rats with ethanol-induced liver injury, which may be related to its anti-apoptotic mechanism.