Article
Physiology
Moriah Hunstiger, Michelle Marie Johannsen, S. Ryan Oliver
Summary: By analyzing the protein expression and metabolites of wild Arctic ground squirrels, it was found that they have different thermoregulation mechanisms during the hibernation season. White adipose tissue does not express uncoupling protein 1, while brown adipose tissue peaks in the expression of uncoupling protein 1 in winter and decreases after arousal in spring. Non-shivering thermogenesis in muscles decreases during hibernation and recovers in spring. These findings suggest distinct thermogenic functions may depend on temperature, resources, and seasonal demands.
FRONTIERS IN PHYSIOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Tatiana S. Filatova, Vladislav S. Kuzmin, Viktoria O. Guskova, Denis Abramochkin
Summary: Hibernating mammals can maintain normal cardiac function at low temperatures due to specific features of the cardiac sodium current, which allows for excitability of the myocardium at low temperatures.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Zachary Carlson, Kelly Drew
Summary: Hibernation is an adaptation that allows animals to survive without food or water. Understanding the mechanisms of metabolic suppression during hibernation could lead to new treatments in critical care. The activation of Adenosine A(1) receptor (A(1)AR) plays a role in hibernation, but its role in seasonal sensitization is unknown. In this study, the A(1)AR in different brain regions of Arctic ground squirrels during summer and torpor seasons was characterized, and the pharmacological characteristics of A(1)AR agonist and antagonist were defined.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Physiology
Nisred K. Klichkhanov, Elena R. Nikitina, Zainab M. Shihamirova, Maria D. Astaeva, Shamil I. Chalabov, Aleksandr I. Krivchenko
Summary: Small ground squirrels exhibit low levels of ROS and RNS production during hibernation, while oxidative stress increases during arousal, but decreases as body temperature recovers.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Physiology
Fiammetta Zanetti, Chao-Yin Chen, Hailey A. Baker, M. Hoshi Sugiura, Kelly L. Drew, Zeinab Barati
Summary: The decrease in heart rate during hibernation is a regulated fall that is mediated by increased cardiac parasympathetic activity, while the increase in heart rate during arousal is driven by the sympathetic nervous system. This study aimed to investigate the temporal information on cardiac parasympathetic regulation throughout a complete hibernation bout. The results showed that parasympathetic activation initiates and regulates the heart rate decrease during entrance into hibernation, while the withdrawal of parasympathetic activation initiates arousal.
PHYSIOLOGICAL AND BIOCHEMICAL ZOOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Rongrong Yin, Jie Zhang, Shenhui Xu, Yong Kong, Huiping Wang, Yunfang Gao
Summary: The study found that iron levels were lower in the femur and liver of torpid squirrels, with bone formation and resorption balanced and no iron overload observed. This may be a potential mechanism for hibernators to avoid disuse-induced bone loss.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Haolin Zhang, Pengyu Chen, Yuxin Liu, Wenqian Xie, Sijie Fan, Yuchen Yao, Yingying Han, Zhengrong Yuan, Qiang Weng
Summary: This study found that testosterone can be converted to estrogen in the prostate of wild ground squirrels, which affects the function of the prostate gland. The conversion process is likely catalyzed by the enzyme P450arom produced by stromal cells, and regulated by locally expressed estrogen receptors. These findings are important for understanding the seasonal regulation mechanisms in the prostate of wild ground squirrels.
JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Khalil Abnous, Kenneth B. Storey
Summary: Hibernation is a crucial winter survival strategy for small mammals, allowing them to conserve energy for extended periods without eating. AMPD plays a key role in managing adenylate pool size during torpor, with hibernating animals showing different AMPD activity and properties compared to euthermic animals. The primary driver of these differences seems to be covalent phosphorylation of AMPD.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
(2021)
Article
Cell Biology
Shannon N. Tessier, W. Aline Ingelson-Filpula, Kenneth B. Storey
Summary: The thirteen-lined ground squirrel is capable of lowering its body temperature to nearly 0 degrees C during hibernation, by downregulating non-essential processes. DNA methylation is a prominent form of epigenetic regulation that helps the squirrel adjust its metabolic rate during hibernation.
MOLECULAR AND CELLULAR BIOCHEMISTRY
(2021)
Article
Multidisciplinary Sciences
S. A. Rice, M. Mikes, D. Bibus, E. Berdyshev, J. A. Reisz, S. Gehrke, I Bronova, A. D'Alessandro, K. L. Drew
Summary: The study found that a diet high in Omega 3 PUFAs with a more balanced Omega 6:3 ratio can increase the core body temperature of Arctic Ground Squirrels during hibernation, primarily through an increase in brown adipose tissue mass. These results suggest that Omega 3 PUFAs may play a role in thermogenesis during hibernation.
SCIENTIFIC REPORTS
(2021)
Article
Zoology
Yue Ren, Shiyi Song, Xinyu Liu, Ming Yang
Summary: Seasonal hibernation in female Daurian ground squirrels leads to changes in behavior, morphology, and metabolism, with high food intake, fat deposition, and body mass increases during fattening compared to hibernation. The levels of serum glucose and triglycerides were higher during fattening, and adiponectin levels were different between fattening and hibernation, suggesting a role in preventing heterotopic fat accumulation and facilitating metabolic switch.
INTEGRATIVE ZOOLOGY
(2022)
Article
Agriculture, Dairy & Animal Science
Xiaoying Yang, Yuchen Yao, Xueying Zhang, Jiahui Zhong, Fuli Gao, Haolin Zhang, Yingying Han, Qiang Weng, Zhengrong Yuan
Summary: This study explored the distinct taxonomy and function of the gut microbiota in the breeding and non-breeding seasons of wild ground squirrels using 16S rRNA gene sequencing technology. The results showed significant differences in microbial composition and function between the two seasons, laying the foundation for further research on the relationship between gut microbiota and seasonal breeding.
Article
Biochemistry & Molecular Biology
Yi Wang, Hongyu Qi, Chunjiao Zhang, Yuanyuan Guo, Yuchen Yao, Xiaohang Feng, Sijie Fan, Yingying Han, Zhengrong Yuan, Qiang Weng, Haolin Zhang
Summary: The study found that the prostate gland of wild ground squirrels significantly increased in size and weight during the breeding season, with a higher density of proliferating cell nuclear antigen (PCNA) in epithelial cells. However, there was no significant difference in apoptosis staining between breeding and nonbreeding seasons. Key cell cycle regulators mTOR, cyclin-D2, p21, p27, and pRB showed distinct expression patterns between different seasons.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2021)
Article
Biology
Shen-Hui Xu, Wei-Wei Fu, Jie Zhang, Hui-Ping Wang, Kai Dang, Hui Chang, Yun-Fang Gao
Summary: The study findings suggest that Daurian ground squirrels may employ different antioxidant strategies in different skeletal muscles during hibernation, influenced by the regulation of PGC-1α and FOXO1 expression. Differential fuel metabolism regulation, possibly enhancing lipid oxidation or maintaining anaerobic glycolysis, could play a role in the formation of antioxidant defense strategies in different types of skeletal muscle fibers.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Zoology
Sara M. Wilbur, Cody E. Deane, Greg A. Breed, C. Loren Buck, Cory T. Williams, Brian M. Barnes
Summary: Hibernation is associated with longer lifespan, with hibernating mammals living 15% longer than nonhibernators on average. Arctic ground squirrels have sex-specific hibernation patterns, with females hibernating 30% longer each year than males. Additionally, male squirrels engage in territory and food defense, which may decrease their survival.
CANADIAN JOURNAL OF ZOOLOGY
(2022)
