Sympathetic Innervation of Brown Adipose Tissue - a Platform to Uncover Fundamental Principles of Developmental Programming

Development of the sympathetic nervous system (SNS) tone onto peripheral organs has been shown to be susceptible to a wide range of external factors, such as temperature. Although it was initially postulated that the sympathetic signal is uniform across the body, there is growing evidence that there can be target-specific sympathetic signals. To date, evidence for a relationship between developmental influences on SNS tone and organ function is purely correlational. An obstacle to investigating the programming of SNS permanently altering physiology is that experimental manipulations of SNS activity during development would impact multiple organ functions simultaneously, which could affect the overall health of the animal and therefore confound interpretation of the results. Here we used brown adipose tissue (BAT) as a platform to define a critical period and identify molecules that contribute to the development of SNS outflow to peripheral organs. In addition, we explored the molecular target-specificity of sympathetic neurons by performing a single-cell RNA sequencing transcriptomic analysis of adult mouse stellate ganglion (SG) in conjunction with retrograde tracing from two of its targets, brown adipose tissue and forelimb. We discovered four molecularly distinct populations of SG neurons that express unique combinations of neuropeptides and receptors, but we did not find evidence of target specificity. The four distinct SG neuronal populations had marker genes that showed unique expression in each population, including genes encoding secreted peptides and receptors of circulating factors. Also, we found that the expression of some of the marker genes differs across the sympathetic chain, which could provide a means for coordinated regulation of SNS responses to specific types of homeostatic challenges

The Role of mAAA protease transmembrane domain in dislocating mitochondrial inner membrane proteins

In eukaryotic cells, the majority of mitochondrial proteins are nuclearly encoded and synthesized in the cytosol. Mitochondrial proteins are targeted to mitochondria via their targeting signals which guide them to specific compartments; outer membrane (OM), intermembrane space (IMS), inner membrane(IM), or matrix. AAA-ATPases(ATP Associated with diverse cellular Activities) are known to be involved in membrane protein degradation and biogenesis. Mitochondria carry two AAA proteases, enzymatic sites of which are in opposite side of the IM; iAAA protease in the IMS and mAAA protease in the matrix. These two AAA proteases are integral membrane proteins themselves in the IM. It has been reported that the transmembrane(TM) domains of mAAA protease is required for integral membrane protein degradation, suggesting that membrane dislocation is essential for degradation as the catalytic domain of mAAA protease is exposed to the matrix side. However, how the mAAA protease recognizes and dislocates integral membrane protein remains unknown. Besides, it is also reported that the activity of mAAA protease is accelerated in cells lacking Prohibitin, a highly conserved protein complex in eukaryotes. This study aims to elucidate the role of TM domains of mAAA protease on the membrane protein recognition and dislocation. By replacing the TM domains of Yta10 and Yta12, which are homologous subunits of mAAA protease with foreign TM segments, it is observed that when the 2nd TM of mAAA protease subunits are replaced, substrate dislocation is reduced. This suggests that the 2nd TM of mAAA proteases is critical in membrane protein dislocation. We also observed that when Prohibitin is absent, substrate dislocation is increased, implying the involvement of Prohibitin complex in dislocation activity of mAAA, and further investigation is underway.OAIID:RECH_ACHV_DSTSH_NO:A201700598RECH_ACHV_FG:RR00200003ADJUST_YN:EMP_ID:A078040CITE_RATE:FILENAME:201701140118_미국학회발표_0116 이서은.pdfDEPT_NM:생명과학부EMAIL:[email protected]_YN:FILEURL:https://srnd.snu.ac.kr/eXrepEIR/fws/file/a696815c-28b8-4248-aedb-9dc3aa46eca1/linkCONFIRM:

Effect of the Marine Exercise Retreat Program on Thyroid-Related Hormones in Middle-Aged Euthyroid Women

This study aimed to investigate the effects of a marine exercise retreat program on thyroid-related hormone levels. A total of 62 middle-aged euthyroid women participated in a 6-day marine exercise retreat program. Using thyroid-stimulating hormone (TSH) and free thyroxine (fT4) hormone levels, the participants were divided into high and low-hormone-level groups. Despite decreased TSH and fT4 levels after the program, the factors influencing changes in each group were different. TSH levels were influenced by changes in the normalized low frequency (nLF) of heart rate variability and carbon monoxide (CO) from all the participants, and changes in body fat percentage, nLF, and nitrogen dioxide (NO2) exposure level in the high TSH group. fT4 levels were influenced by changes in body mass index (BMI), NO2 exposure, and particulate matter diameter of 10 µm or less (PM10) exposure in all participants. Changes in BMI and CO exposure influenced the low fT4 group. Lastly, changes in the exercise stress test affected the high fT4 group. Thus, the marine exercise retreat program affected euthyroid thyroid-related hormone levels, and influencing factors differ depending on the initial value of the hormone

Rearing mice at 22°C programs increased capacity to respond to chronic exposure to cold but not high fat diet

Objective: Rodent models raised at environmental temperatures of 21–22 °C are increasingly switched to thermoneutral housing conditions in adulthood to better capture human physiology. We quantified the developmental effects of rearing mice at an ambient temperature of 22 °C vs. 30 °C on metabolic responses to cold and high fat diet (HFD) in adulthood. Methods: Mice were reared from birth to 8 weeks of age at 22 °C or 30 °C, when they were acclimated to single housing at the same temperature for 2–3 weeks in indirect calorimetry cages. Energy expenditure attributable to basal metabolic rate, physical activity, thermic effect of food, and adaptive cold- or diet-induced thermogenesis was calculated. Responses to cooling were evaluated by decreasing the ambient temperature from 22 °C to 14 °C, while responses to HFD feeding were assessed at 30 °C. Influences of rearing temperature on thermogenic responses that emerge over hours, days and weeks were assessed by maintaining mice in the indirect calorimetry cages throughout the study. Results: At an ambient temperature of 22 °C, total energy expenditure (TEE) was 12–16% higher in mice reared at 22 °C as compared to 30 °C. Rearing temperature had no effect on responses in the first hours or week of the 14 °C challenge. Differences emerged in the third week, when TEE increased an additional 10% in mice reared at 22 °C, but mice reared at 30 °C could not sustain this level of cold-induced thermogenesis. Rearing temperature only affected responses to HFD during the first week, due to differences in the timing but not the strength of metabolic adaptations. Conclusion: Rearing at 22 °C does not have a lasting effect on metabolic adaptations to HFD at thermoneutrality, but it programs an enhanced capacity to respond to chronic cold challenges in adulthood. These findings highlight the need to consider rearing temperature when using mice to model cold-induced thermogenesis

The Mgr2 subunit of the TIM23 complex regulates membrane insertion of marginal stop‐transfer signals in the mitochondrial inner membrane

International audienc

Changes in cortisol awakening responses (CAR) in menopausal women through short-term marine healing retreat program with specific factors affecting each CAR index

Recent studies have reported that the cortisol awakening response (CAR) is associated with various health risks. The different indices used to represent the CAR include the average cortisol levels in the morning immediately after waking (AVE); the total area under the curve of cortisol levels with respect to ground (AUCg); and the area under the curve of cortisol levels with respect to increase (AUCi). However, it is unclear which physiological phenomenon each index reflects. This study investigated the factors, such as stress, circadian rhythm, sleep, and obesity, affecting the CAR through a marine retreat-based healing program in which the anticipated stress of the participants could be controlled to some degree. Fifty-one menopausal women in their 50s and 60s were included, who performed beach yoga and Nordic walking for four days at an uncontaminated beach. The baseline CAR indices showed that the AVE and AUCg were significantly higher in the high sleep efficiency group than in the low sleep efficiency group. However, the AUCi decreased substantially with increasing age. The changes in the AVE, AUCg, and AUCi were calculated through the program, and it was found that the AVE and AUCg increased significantly more in the obese group than in the normal and overweight groups. The obese group also showed significantly decreased serum triglyceride and BDNF (brain-derived neurotrophic factor) levels compared to the low BMI group. Thus, it was confirmed that AVE and AUCg reflected physiological phenomena affected by factors such as sleep efficiency and obesity, whereas the AUCi was affected by factors such as age. In addition, the marine retreat program can improve the low levels of CAR associated with obesity and aging

Changes in cortisol awakening responses (CAR) in menopausal women through short-term marine healing retreat program with specific factors affecting each CAR index.

Recent studies have reported that the cortisol awakening response (CAR) is associated with various health risks. The different indices used to represent the CAR include the average cortisol levels in the morning immediately after waking (AVE); the total area under the curve of cortisol levels with respect to ground (AUCg); and the area under the curve of cortisol levels with respect to increase (AUCi). However, it is unclear which physiological phenomenon each index reflects. This study investigated the factors, such as stress, circadian rhythm, sleep, and obesity, affecting the CAR through a marine retreat-based healing program in which the anticipated stress of the participants could be controlled to some degree. Fifty-one menopausal women in their 50s and 60s were included, who performed beach yoga and Nordic walking for four days at an uncontaminated beach. The baseline CAR indices showed that the AVE and AUCg were significantly higher in the high sleep efficiency group than in the low sleep efficiency group. However, the AUCi decreased substantially with increasing age. The changes in the AVE, AUCg, and AUCi were calculated through the program, and it was found that the AVE and AUCg increased significantly more in the obese group than in the normal and overweight groups. The obese group also showed significantly decreased serum triglyceride and BDNF (brain-derived neurotrophic factor) levels compared to the low BMI group. Thus, it was confirmed that AVE and AUCg reflected physiological phenomena affected by factors such as sleep efficiency and obesity, whereas the AUCi was affected by factors such as age. In addition, the marine retreat program can improve the low levels of CAR associated with obesity and aging

Study on Verifying the Effectiveness of Non-face-to-face Youth Volunteering in Improving Self-Esteem Among Children of Deaf Adults (CODAs)

The goal of this study is to evaluate the effectiveness of youth volunteering in increasing the self-esteem of hearing children of deaf adults (CODAs), who commonly start taking care of their parents from a young age. To this end, an experimental study based on the non-equal comparison groups design was applied to a experimental group of 4 participants and a control group of 3 participants, selected based on the recommendation from expert social workers from the M General Social Welfare Center in P City. The volunteer programs, conducted non-face-to-face due to COVID-19, were centered on art activities such as drawing one's own dreams, decorating flowers, and customizing pencil cases. Repeated measures analysis of variance (rANOVA) was conducted to verify the effectiveness of volunteering, and the analysis results are as follows. First, in both the experimental group and the control group, CODAs' self esteem increased after the program was carried out. Second, while the growth effect appeared in both groups, the slope of increase in the self-esteem of the experimental group was significantly higher than that of the control group. Accordingly, the effectiveness of volunteering to improve CODAs' self-esteem was verified. This study suggests academic and practical implications based on these findings