Breeder Diet Strategies for Generating Ttpa-Null and Wild-Type Mice with Low Vitamin E Status to Assess Neurological Outcomes

Abstract

Studying vitamin E (α-tocopherol, α-T) metabolism and function in the brain and other tissues requires an animal model with low α-T status, such as the α-T transfer protein-null (Ttpa−/−) mouse model. Ttpa+/− dams can be used to produce Ttpa−/− and Ttpa+/+mice for these studies. However, the α-T content in Ttpa+/− dams’ diet requires optimization; diets must provide sufficient α-T for reproduction, while minimizing the transfer of α-T to the offspring destined for future studies that require low baseline α-T status. The goal of this work was to assess the effectiveness and feasibility of two breeding diet strategies on reproduction outcomes and offspring brain α-T concentrations. These findings will help standardize the breeding methodology used to generate the Ttpa−/− mice for neurological studies.

Natural and Synthetic α-Tocopherol Modulate the Neuroinflammatory Response in the Spinal Cord of Adult Ttpa-null Mice

“…These Ttpa +/ − mice were then bred to generate Ttpa +/+ and Ttpa − / − offspring to be used for the current study. The low-vitamin-E breeder diet minimized brain α-T concentrations in the Ttpa − / − mice weanlings (3.38 ± 0.64 nmol/g), similar to previous reports ( 9 , 25 , 28 ).…”

“…Notably, methodological differences may also partially explain why the current study results do not corroborate our previous study using adolescent mice. In the previous study, female Ttpa +/ − breeders received a standard AIN-93G diet containing α-T during the initial gestation period (days 1–9) followed by a VED diet for the remainder of gestation and lactation ( 25 , 28 ). In contrast, breeders for the current adult study received a low-vitamin-E diet for the entire breeding period ( 28 ).…”

“…In the previous study, female Ttpa +/ − breeders received a standard AIN-93G diet containing α-T during the initial gestation period (days 1–9) followed by a VED diet for the remainder of gestation and lactation ( 25 , 28 ). In contrast, breeders for the current adult study received a low-vitamin-E diet for the entire breeding period ( 28 ). Both breeder diet strategies successfully minimized the transfer of α-T to offspring; 3-wk-old Ttpa − / − weanlings had very low brain α-T concentrations regardless of the breeder diet strategy.…”

“…Ttpa − / − males were crossed with C57BL/6 ( Ttpa +/+ ) females to produce heterozygous Ttpa +/ − mice. Female Ttpa +/ − offspring were fed a previously described AIN-93G–based low-vitamin-E diet [35 mg all- rac –α-tocopheryl acetate (-α-TA)/kg diet] ( 28 ). These Ttpa +/ − mice were then bred to generate Ttpa +/+ and Ttpa − / − offspring to be used for the current study.…”

α-Tocopherol Transfer Protein-Null Mice with Very Low α-Tocopherol Status Do Not Have an Enhanced Lipopolysaccharide-Induced Acute Inflammatory Response

“…The University of Illinois Institutional Animal Care and Use Committee approved all animal procedures. Study mice were generated using a trio-breeder strategy [ 30 ]. Briefly, male Ttpa −/− and female C57BL6 ( Ttpa +/+ ) were crossed to generate Ttpa +/− mice.…”