Dietary restriction（DR） can delay senescence, prolong lifespan of mammals and improve their learning-memory activity. The purpose of the study was to explore the effects of DR on hypolipidemic action and liver funct...Dietary restriction（DR） can delay senescence, prolong lifespan of mammals and improve their learning-memory activity. The purpose of the study was to explore the effects of DR on hypolipidemic action and liver function of mice with hyperlipidemia. To investigate these effects, hyperlipidemia mouse models were established with high-fat diet（HFD）（34% of energy）, then randomly divided into HFD group, DR30% group and DR50% group. Mice in DR30% and DR50% group were respectively supplied with HFD as much as about 70% and 50% of the consumption of HFD in the mice of HFD group. Rats in control group were fed routinely. After DR for 5 weeks, the average body weight, liver weight, liver index, serum lipids and glucose levels in both DR groups decreased significantly as compared with the HFD group（P〈0.05 or P〈0.01）, so did alanine aminotransferase（ALT）, aspartate aminotransferase（AST）, lactate dehydrogenase（LDH） levels and the ratio of LDL-C/HDL-C in the DR50% group（P〈0.05 or P〈0.01）. Histopathology examination of liver tissues further proved ameliorative effect of DR on liver function. Western blotting showed that DR significantly increased the expression of silent mating type information regulation 2 homolog 1（SIRT1） in liver and adipose, while notably decreased the expression of peroxisome proliferators-activated receptors-gamma（PPARγ） in adipose（P〈0.05 or P〈0.01）. The increase of SIRT1 and decrease of PPARγ may be a mechanism by which DR reduces blood lipids and ameliorates liver function.展开更多
The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to dev...The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of hurnans. The choice of rats in cognition research studies has specific advantages in that these anirnals possess similar pharrnacodynamic parameters to hurnans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the perforrnance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of thed also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous systern responsivencess of rat strains to chemicals and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessrnent of neurobehavioural functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models.展开更多
基金supported by a grant from the Social Development Research Program of Science and Technology Agency of Jiangsu Province(No.BE2015646)
文摘Dietary restriction（DR） can delay senescence, prolong lifespan of mammals and improve their learning-memory activity. The purpose of the study was to explore the effects of DR on hypolipidemic action and liver function of mice with hyperlipidemia. To investigate these effects, hyperlipidemia mouse models were established with high-fat diet（HFD）（34% of energy）, then randomly divided into HFD group, DR30% group and DR50% group. Mice in DR30% and DR50% group were respectively supplied with HFD as much as about 70% and 50% of the consumption of HFD in the mice of HFD group. Rats in control group were fed routinely. After DR for 5 weeks, the average body weight, liver weight, liver index, serum lipids and glucose levels in both DR groups decreased significantly as compared with the HFD group（P〈0.05 or P〈0.01）, so did alanine aminotransferase（ALT）, aspartate aminotransferase（AST）, lactate dehydrogenase（LDH） levels and the ratio of LDL-C/HDL-C in the DR50% group（P〈0.05 or P〈0.01）. Histopathology examination of liver tissues further proved ameliorative effect of DR on liver function. Western blotting showed that DR significantly increased the expression of silent mating type information regulation 2 homolog 1（SIRT1） in liver and adipose, while notably decreased the expression of peroxisome proliferators-activated receptors-gamma（PPARγ） in adipose（P〈0.05 or P〈0.01）. The increase of SIRT1 and decrease of PPARγ may be a mechanism by which DR reduces blood lipids and ameliorates liver function.
文摘The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of hurnans. The choice of rats in cognition research studies has specific advantages in that these anirnals possess similar pharrnacodynamic parameters to hurnans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the perforrnance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of thed also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous systern responsivencess of rat strains to chemicals and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessrnent of neurobehavioural functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models.
