<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Alteration in gravitational load impacts homeorhetic response in rat dams which affects neonatal pup survival. However, the effects of hypergravity (HG) exposure on the abundance of apoptosis-associated proteins in mammary epithelial cells (MECs) have not been characterized. Therefore, we examined whether chronic exposure to HG from midpregnancy alters the abundance of proapoptotic proteins in MECs during the late pregnancy and early lactation. A group of pregnant Sprague Dawley rats were exposed to either HG (2g) or normo-gravity (1g: stationary control [SC]) from days 11 to 20 of gestation (G20). Another set of animals were investigated from day 11 of pregnancy through days 1 and 3 (P1 and P3, respectively) postpartum. Quantitative (pixels [px]/lobule) immunohistochemistry at G20 of Cleaved Caspase-3 (CC-3), Tumor Protein p53 (P53), and vitamin D receptor (VDR) revealed that all the three proteins were increased (p&lt;0.01) in HG rats compared to SC animals. At P1, the HG group had twofold higher (p&lt;0.001) expression of CC-3 relative to the SC group. Approximately, 50% (p&lt;0.001) more VDR was detected in the HG cohorts than SC at P3. These results suggest that a shift in g-load upregulates the expression of key proapoptotic proteins during the pregnancy-to-lactation transition in the rat MECs.</p></abstract>

Alteration in gravitational load impacts homeorhetic response in rat dams which affects neonatal pup survival. However, the effects of hypergravity (HG) exposure on the abundance of apoptosis-associated proteins in mammary epithelial cells (MECs) have not been characterized. Therefore, we examined whether chronic exposure to HG from midpregnancy alters the abundance of proapoptotic proteins in MECs during the late pregnancy and early lactation. A group of pregnant Sprague Dawley rats were exposed to either HG (2g) or normo-gravity (1g: stationary control [SC]) from days 11 to 20 of gestation (G20). Another set of animals were investigated from day 11 of pregnancy through days 1 and 3 (P1 and P3, respectively) postpartum. Quantitative (pixels [px]/lobule) immunohistochemistry at G20 of Cleaved Caspase-3 (CC-3), Tumor Protein p53 (P53), and vitamin D receptor (VDR) revealed that all the three proteins were increased (p<0.01) in HG rats compared to SC animals. At P1, the HG group had twofold higher (p<0.001) expression of CC-3 relative to the SC group. Approximately, 50% (p<0.001) more VDR was detected in the HG cohorts than SC at P3. These results suggest that a shift in g-load upregulates the expression of key proapoptotic proteins during the pregnancy-to-lactation transition in the rat MECs.

Impact of <italic>g</italic>-Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

Gravitational and Space Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Impact of -Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

Alteration in gravitational load impacts homeorhetic response in rat dams which affects neonatal pup survival. However, the effects of hypergravity (HG)...

Impact of g-Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

Article Category: Short Communication

Publié en ligne: 17 juin 2019

Pages: 13 - 21

DOI: https://doi.org/10.2478/gsr-2019-0003

Mots clés
Rat, Mammary Gland, Gravity, Apoptosis, Lactation, Pregnancy, Immunohistochemistry

© 2019 Kibrom M. Alula, James H. Resau, Osman V. Patel, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Impact of g-Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

Article Category: Short Communication

Publié en ligne: 17 juin 2019

Pages: 13 - 21

DOI: https://doi.org/10.2478/gsr-2019-0003

Mots clésRat, Mammary Gland, Gravity, Apoptosis, Lactation, Pregnancy, Immunohistochemistry

© 2019 Kibrom M. Alula, James H. Resau, Osman V. Patel, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Mots clés
Rat, Mammary Gland, Gravity, Apoptosis, Lactation, Pregnancy, Immunohistochemistry