Age-related Changes in Brain Regional Activity during Chewing: A Functional Magnetic Resonance Imaging Study

2003 ◽  
Vol 82 (8) ◽  
pp. 657-660 ◽  
Author(s):  
M. Onozuka ◽  
M. Fujita ◽  
K. Watanabe ◽  
Y. Hirano ◽  
M. Niwa ◽  
...  

Age-related changes in mastication-induced brain neuronal activity have been suggested. However, in humans, little is known about the anatomical regions involved. Using fMRI during cycles of rhythmic gum-chewing and no chewing, we have examined the effect of aging on brain regional activity during chewing in young adult (19–26 yrs), middle-aged (42–55 yrs), and aged (65–73 yrs) healthy humans. In all subjects, chewing resulted in a bilateral increase in the BOLD signals in the sensorimotor cortex, cerebellum, thalamus, supplementary motor area, and insula, and a unilateral increase in the right prefrontal area. In the first three regions, the signal increases were attenuated in an age-dependent manner, whereas, in the right prefrontal area, the converse was seen. The remaining two regions showed no significant differences with ages. These results indicate that chewing causes regional increases in neuronal activity in the brain, some of which are age-dependent.

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
James Moore ◽  
Rashid Akbergenov ◽  
Martina Nigri ◽  
Patricia Isnard-Petit ◽  
Amandine Grimm ◽  
...  

AbstractRandom errors in protein synthesis are prevalent and ubiquitous, yet their effect on organismal health has remained enigmatic for over five decades. Here, we studied whether mice carrying the ribosomal ambiguity (ram) mutation Rps2-A226Y, recently shown to increase the inborn error rate of mammalian translation, if at all viable, present any specific, possibly aging-related, phenotype. We introduced Rps2-A226Y using a Cre/loxP strategy. Resulting transgenic mice were mosaic and showed a muscle-related phenotype with reduced grip strength. Analysis of gene expression in skeletal muscle using RNA-Seq revealed transcriptomic changes occurring in an age-dependent manner, involving an interplay of PGC1α, FOXO3, mTOR, and glucocorticoids as key signaling pathways, and finally resulting in activation of a muscle atrophy program. Our results highlight the relevance of translation accuracy, and show how disturbances thereof may contribute to age-related pathologies.


2020 ◽  
pp. 14-18
Author(s):  
Татьяна Александровна Цехмистренко ◽  
Аслан Батразович Мазлоев ◽  
Дмитрий Константинович Обухов

Цель - изучение возрастных изменений толщины коры и ее слоев в парамедианной дольке мозжечка у детей. Материал и методы. Работа выполнена на постмортальном материале (62 мозжечка), полученном от детей в возрасте от рождения до 12 лет, умерших в результате травм без повреждений головного мозга. С помощью компьютерной морфометрии на окрашенных методом Ниссля фронтальных гистологических срезах коры, взятой билатерально в области парамедианной (тонкой) дольки (HVIIB) на вершине листков мозжечка, измеряли толщину коры, а также толщину ее молекулярного и зернистого слоев. Анализ количественных данных проводили в годовых интервалах. Результаты. В парамедианной дольке мозжечка увеличение толщины коры происходит в четыре этапа: в правом полушарии - от рождения к 1, 3, 5 и 9 годам, в левом полушарии - к 1, 5, 7 и 9 годам. Левосторонняя асимметрия толщины коры мозжечка отмечается у детей 1 и 2 лет, толщины молекулярного слоя - у детей 3 лет жизни. Правосторонняя асимметрия характерна для толщины зернистого слоя у детей 3 лет и поперечника коры, в целом, у детей 6 лет. Толщина коры и слоев в области парамедианной дольки мозжечка по среднегрупповым показателям достигает уровня взрослых людей к 9 годам. Выводы. Толщина коры мозжечка и ее слоев в области дольки H VII B увеличивается гетерохронно и гетеродинамически в правом и левом полушариях мозжечка у детей на первом году жизни, а также в периоды раннего, первого и второго детства. Уменьшения поперечника коры и слоев в парамедианной дольке мозжечка у детей от рождения до 12 лет не обнаружено. Objective - to study the age-related changes in the thickness of the cortex and its layers in the paramedian lobule of the cerebellum in children. Material and methods. The work was performed on postmortem material (62 cerebellums) obtained from children aged from birth to 12 years who died from injuries but without brain damage. The thickness of the cortex, as well as the thickness of its molecular and granular layers, were measured using computer morphometry on the Nissl-stained frontal histological sections of the cortex taken bilaterally in the region of the paramedian (gracile) lobule (HVIIB) at the top of the folia of cerebellum. Analysis of quantitative data was performed at annual intervals. Results. In the paramedian lobule of the cerebellum, the increase in the thickness of the cortex occured in four stages: in the right hemisphere - from birth to 1, 3, 5 and 9 years, in the left hemisphere - to 1, 5, 7 and 9 years. Left-sided asymmetry of the cortical thickness of the cerebellum was observed in 1 and 2-year old children, the thickness of the molecular layer - in 3-year old children. Right-sided asymmetry was characteristic for the thickness of the granular layer in 3-year old children and a cross-section of the cortex in 6-year old children. The thickness of the cortex and layers in the area of the paramedian lobule of the cerebellum on the average group indicators reached the level of adults by 9 years. Conclusions. The thickness of the cerebellar cortex and its layers in the area of the lobule HVIIB increased heterochronically and heterogeneously in the right and left hemispheres of the cerebellum in children of the first year of life, and in the periods of early, first and second childhood. No reduction in the diameter of the cortex and layers in the paramedian lobule of the cerebellum of children from birth to 12 years was found.


2015 ◽  
Vol 93 (3) ◽  
pp. 151-159 ◽  
Author(s):  
David Qixiang Chen ◽  
Ido Strauss ◽  
Dave J. Hayes ◽  
Karen D. Davis ◽  
Mojgan Hodaie

2006 ◽  
Vol 291 (6) ◽  
pp. F1177-F1183 ◽  
Author(s):  
Monique van Abel ◽  
Sylvie Huybers ◽  
Joost G. J. Hoenderop ◽  
Annemiete W. C. M. van der Kemp ◽  
Johannes P. T. M. van Leeuwen ◽  
...  

Aging is associated with alterations in Ca2+ homeostasis, which predisposes elder people to hyperparathyroidism and osteoporosis. Intestinal Ca2+ absorption decreases with aging and, in particular, active transport of Ca2+ by the duodenum. In addition, there are age-related changes in renal Ca2+ handling. To examine age-related changes in expression of the renal and intestinal epithelial Ca2+ channels, control (TRPV5+/+) and TRPV5 knockout (TRPV5−/−) mice aged 10, 30, and 52 wk were studied. Aging of TRPV5+/+ mice resulted in a tendency toward increased renal Ca2+ excretion and significantly decreased intestinal Ca2+ absorption, which was accompanied by reduced expression of TRPV5 and TRPV6, respectively, despite increased serum 1,25(OH)2D3 levels. Similarly, in TRPV5−/− mice the existing renal Ca2+ loss was more pronounced in elder animals, whereas the compensatory intestinal Ca2+ absorption and TRPV6 expression declined with aging. In both mice strains, aging resulted in a resistance to 1,25(OH)2D3 and diminished renal vitamin D receptor mRNA levels, whereas serum Ca2+ levels remained constant. Furthermore, 52-wk-old TRPV5−/− mice showed severe hyperparathyroidism, whereas PTH levels in elder TRPV5+/+ mice remained normal. In 52-wk-old TRPV5−/− mice, serum osteocalcin levels were increased in accordance with the elevated PTH levels, suggesting an increased bone turnover in these mice. In conclusion, downregulation of TRPV5 and TRPV6 is likely involved in the impaired Ca2+ (re)absorption during aging. Moreover, TRPV5−/− mice likely develop age-related hyperparathyroidism and osteoporotic characteristics before TRPV5+/+ mice, demonstrating the importance of the epithelial Ca2+ channels in Ca2+ homeostasis.


2020 ◽  
Vol 15 (2) ◽  
pp. 61-67
Author(s):  
Fatema Johora ◽  
Abu Sadat Mohammad Nurunnabi ◽  
Dilruba Siddiqua ◽  
Hasna Hena ◽  
Shamim Ara

Background: Changes in the size of the kidney are evident in humans, as age progresses. Objective: To see the age-related changes in the morphological dimensions of the kidney in a sample of the Bangladeshi population. Methods: This crosssectional study was done in the Department of Anatomy, Dhaka Medical College, Dhaka, from July 2008 to June 2009, based on a collection of 140 postmortem human kidneys collected from 70 unclaimed dead bodies from the morgue of the same institution. All the samples of kidney were divided into three age groups, including A (10-19 years), B (20-39 years) and C (40-59 years). The length, breadth and thickness of all the kidneys were measured by using a slide calipers and recorded. Data were expressed as mean±SD. For statistical analysis, independent sample t test and one way ANOVA was used. Results: The length of the right and left kidneys found were 8.72±0.25 cm and 9.28±0.12 cm; 9.73±0.35 cm and 10.31±0.41 cm; 9.68±0.21 cm and 10.24±0.06 cm in group A, B and C respectively. The breadth of the right and left kidneys found were 4.32±0.09 cm and 4.22±0.11 cm; 4.74±0.29 cm and 4.55±0.28 cm; 4.61±0.21 cm and 4.44±0.21 cm in group A, B and C respectively. The thickness of the right and left kidneys found were 2.84±0.10 cm and 2.64±0.05 cm; 3.31±0.16 cm and 3.11±0.10 cm; 3.17±0.07 cm and 3.11±0.10 cm in group A, B and C respectively. The mean length of the left kidneys was found significantly greater than that of the right , whereas the mean breadth and the thickness of the right kidneys were found greater than that of the left kidney in all age groups. Moreover, age related changes were significant in all dimensions (length, breadth and thickness) of the kidney when compared between group A & B and A & C. Conclusion: This study results concluded that the length of the left kidney was greater than that of the right, but the breadth and the thickness of the right kidney were greater than that of the left one in all age groups. In addition, age related changes in all dimensions (i.e. length, breadth and thickness) of the kidneys were evident in middle age versus young adult and older adult versus young adult. J Bangladesh Soc Physiol. 2020, December; 15(2): 61-67


2006 ◽  
Vol 61 (5) ◽  
pp. 513-518 ◽  
Author(s):  
Aušra BURKAUSKICNÉ ◽  
Zygmunt MACKIEWICZ ◽  
Ismo VIRTANEN ◽  
Yrjö T. KONTTINEN

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Marta Maglione ◽  
Gaga Kochlamazashvili ◽  
Tobias Eisenberg ◽  
Bence Rácz ◽  
Eva Michael ◽  
...  

AbstractAging is associated with functional alterations of synapses thought to contribute to age-dependent memory impairment (AMI). While therapeutic avenues to protect from AMI are largely elusive, supplementation of spermidine, a polyamine normally declining with age, has been shown to restore defective proteostasis and to protect from AMI in Drosophila. Here we demonstrate that dietary spermidine protects from age-related synaptic alterations at hippocampal mossy fiber (MF)-CA3 synapses and prevents the aging-induced loss of neuronal mitochondria. Dietary spermidine rescued age-dependent decreases in synaptic vesicle density and largely restored defective presynaptic MF-CA3 long-term potentiation (LTP) at MF-CA3 synapses (MF-CA3) in aged animals. In contrast, spermidine failed to protect CA3-CA1 hippocampal synapses characterized by postsynaptic LTP from age-related changes in function and morphology. Our data demonstrate that dietary spermidine attenuates age-associated deterioration of MF-CA3 synaptic transmission and plasticity. These findings provide a physiological and molecular basis for the future therapeutic usage of spermidine.


1982 ◽  
Vol 100 (1) ◽  
pp. 18-24 ◽  
Author(s):  
M. Berger ◽  
Ch. Jean-Faucher ◽  
M. De Turckheim ◽  
G. Veyssière ◽  
CI. Jean

Abstract. Male rabbits were castrated at infantile (30 days), peripubertal (60 days) and adult (7–8 months) stages. Two different doses of testosterone were injected 10 days after castration (5 injections at 12 h intervals). Plasma LH and FSH were determined by RIA 1,5 and 10 days after castration and 1 h after the last injection of testosterone. The response of both gonadotrophins to castration was age-dependent. In 30 day old castrated males LH was not significantly modified and FSH had increased only 10 days after castration. In 60 day old and adult males FSH and LH levels were increased 24 h after castration and continued to rise as time progressed. For both gonadotrophins, the response of adult males to castration was higher than that of immature animals. At all stages studied, the highest dose of testosterone (250 μg/kg body weight) depressed post-castration LH and FSH levels. Twenty-five μg of testosterone per kg body weight was effective to depress LH levels only in 30 day old males, suggesting a change in the hypothalamic-pituitary unit to the negative feedback of androgens. These findings suggest that there are marked changes in the hypothalamic-pituitary unit around the beginning of the peripubertal stage. These changes could play a determinant role in the onset of puberty.


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