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[Effects of abnormal nutritional supply during pregnancy on adult hormone resistance in rats]
Wei-wei Song1, Tao Shang, Hong-bo Liu
1Department of Obstetrics and Gynecology, the Second Affiliated Hospital, China Medical University, Shenyang, China.
Insights
Maternal nutrition during pregnancy impacts offspring health. Both low and high birth weight in adult rats exhibit distinct obesity patterns and resistance to insulin and leptin.
Area of Science:
- Reproductive biology and developmental toxicology.
- Metabolic disease research.
- Animal models in biomedical research.
Context:
- Maternal nutrition during gestation is critical for fetal development.
- Nutritional imbalances can lead to altered birth weights, such as small for gestational age (SGA) and large for gestational age (LGA) offspring.
- These conditions may have long-term metabolic consequences in adulthood.
Purpose:
- To investigate the long-term effects of abnormal maternal nutrition on insulin and leptin resistance in adult rats.
- To compare the metabolic profiles of offspring with low (SGA) and high (LGA) birth weights.
Summary:
- Pregnant rats were fed either a low-protein or high-nutrition diet, with a normal diet group as control.
- Offspring were categorized as SGA, LGA, or normal birth weight and studied at 4 and 12 weeks post-birth.
- Measurements included body weight, fat-to-body weight ratio, insulin and leptin levels, and insulin sensitivity index (ISI).
Impact:
- Abnormal maternal nutrition resulted in altered birth weights (SGA and LGA).
- Both SGA and LGA rats displayed increased adiposity and insulin and leptin resistance in adulthood.
- These findings highlight the lasting metabolic impact of prenatal nutritional disturbances.
Objective:
To discuss the effects of abnormal nutritional supply during pregnancy on the adult insulin and leptin resistance in rats.
Methods:
We established the pregnant rat models given either low protein or high nutrition diet, and normal diet group served as control. There were 12 pregnant rats in each group. After vaginal delivery, the pups birth weight were measured. The randomly selected small for gestational age (SGA) from low protein diet group, large for gestational age (LGA) pups from high nutrition diet group and normal birth weight pups from control group were studied at both 4 weeks and 12 weeks after being born. Each group contained 36 rats. The insulin and leptin level were measured by the method of ELISA, and insulin sensitive index were calculated respectively.
Results:
The pups of mothers served with low protein showed obviously lower birth weight than those mothers with normal diet (P < 0.01), 69% pups were SGA. While pups of mothers with high nutrition diet showed obviously higher birth weight than those mothers with normal diet (P < 0.01), 38% were LGA. The body weight of rats in SGA group was similar with those in control group at 4-week-age (P > 0.05), while the weight of fat around kidney, the ratio of fat and body weight (FW/BW) were (0.36 +/- 0.14) g, 6.5 +/- 0.3, which were higher than those of control (0.19 +/- 0.13) g, 3.4 +/- 0.3 (P < 0.01, P < 0.05). FW/BW in LGA group showed no obvious difference from that of control. At 12-week-age, the body weight of SGA was (222 +/- 19) g, that of LGA was (257 +/- 24) g, both of them significantly higher than that of control (215 +/- 25) g (P < 0.05, P < 0.01). FW/BW in SGA was 10.5 +/- 5.1, in LGA it was 11.8 +/- 3.6, which were significantly higher than that of control, 7.2 +/- 3.6 (P < 0.01). The higher insulin (5.5 +/- 0.9) microg/L, leptin (6.1 +/- 0.7) microg/L level and lower ISI (3.4 +/- 0.3) were obvious at 4-week-age (all P < 0.05) in SGA group but not in LGA group. At 12-week-age, all of them in the two groups were significantly different compared with those in control (all P < 0.01).
Conclusions:
Abnormal nutritional supply during pregnancy can lead to abnormal birth weight. Both low birth weight and high birth weight pups showed obesity with different characteristics and insulin, leptin resistance during adult period.
