Genetic influence on electrocardiogram time intervals and heart rate in aging mice

Understanding the genetic influence on ECG time intervals and heart rate (HR) is important for identifying the genes underlying susceptibility to cardiac arrhythmias. The objective of this study was to determine the genetic influence on ECG parameters and their age-related changes in mice. ECGs were recorded in lead I on 8 males and 8 females from each of 28 inbred strains at the ages of 6, 12, and 18 mo. Significant interstrain differences in the P-R interval, QRS complex duration, and HR were found. Age-related changes in the P-R interval, QRS complex duration, and HR differed among strains. The P-R interval increased with age in 129S1/SvlmJ females. The QRS complex duration decreased with age in C57BR/J males and DBA2/J females but increased in NON/ShiLtJ females. HR decreased in C57L/J females and SM/J and P/J males but increased in BALB/cByJ males. Differences between males and females were found for HR in SJL/J mice and in the P-R interval in 129S1/SvlmJ mice. Broad-sense heritability estimates of ECG time intervals and HR ranged from 0.31 for the QRS complex duration to 0.52 for the P-R interval. Heritability estimates decreased with age for the P-R interval. Our study revealed that genetic factors play a significant role on cardiac conduction activity and age-related changes in ECG time intervals and HR.

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Age-related changes in the TRB and IGH repertoires in healthy adult males and females

Immunology Letters ◽

10.1016/j.imlet.2021.10.002 ◽

2021 ◽

Author(s):

Mingxing Gong ◽

Xueying Li ◽

Anqi Zheng ◽

Hongxu Xu ◽

Shi Xie ◽

...

Keyword(s):

Healthy Adult ◽

Adult Males ◽

Age Related ◽

Males And Females ◽

Age Related Changes

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Gender Differences in Large Artery Stiffness Pre- and Post Puberty

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2003-030722 ◽

2003 ◽

Vol 88 (11) ◽

pp. 5375-5380 ◽

Cited By ~ 105

Author(s):

Anna A. Ahimastos ◽

Melissa Formosa ◽

Anthony M. Dart ◽

Bronwyn A. Kingwell

Keyword(s):

Gender Differences ◽

Heart Rate ◽

Cardiac Output ◽

Arterial Compliance ◽

Large Artery ◽

Healthy Children ◽

Large Arteries ◽

Age Related ◽

Artery Stiffness ◽

Males And Females

Abstract Age-related large artery stiffening is more pronounced in women compared with men and is an important cause of isolated systolic hypertension. This study aimed to investigate whether such gender differences are inherent or the result of sex steroid influences. Healthy children prepuberty [26 female (10.3 ± 0.1 yr), 32 male (10.3 ± 0.1 yr), mean age ± sd] and post puberty [30 female (15.9 ± 0.2 yr), 22 male (15.9 ± 0.4 yr)] were studied. Large artery stiffness was assessed globally via systemic arterial compliance and regionally via pulse wave velocity. Prepubertal males and females did not differ in body size, cardiac output, or heart rate. Prepubertal females had stiffer large arteries and higher pulse pressure than age-matched males (P < 0.05). Postpubertal males were taller and heavier and had a greater cardiac output and lower heart rate compared with similarly aged females. In relation to pubertal status, females developed more distensible large arteries post puberty whereas males developed stiffer large vessels (P < 0.05). These changes where such that central large artery stiffness was similar between genders in the postpubertal group. Together these data suggest that large artery stiffness varies intrinsically between genders but is also modulated by both male and female sex steroids.

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Changes with age of mammary glands in male and female soft-furred rat, Millardia meltada, in relation to prolactin and testosterone

Laboratory Animals ◽

10.1258/002367794781065690 ◽

1994 ◽

Vol 28 (1) ◽

pp. 35-43

Author(s):

H. Nagasawa ◽

T. Mori ◽

S. Sakamoto ◽

S. Sassa ◽

Y. Yamamuro ◽

...

Keyword(s):

Enzyme Activities ◽

De Novo ◽

Serum Levels ◽

Mammary Glands ◽

Ventral Prostate ◽

Male And Female ◽

Age Related ◽

Males And Females ◽

Salvage Pathways ◽

Age Related Changes

The soft-furred rat, millardia ( Millardia meltada), is characterized by the development of androgen-dependent mammary tumours only in males. The age-related changes of the activities of thymidylate synthetase (TS) and thymidine kinase (TK), which contribute to DNA synthesis through de novo and salvage pathways, respectively, and structure in the mammary glands were studied in both males and females of this species between 5-28 months of age. While TK activity had no relation to age, TS activity decreased with age in males. In the females, TK activity increased with age, but not TS activity. These enzyme activities were generally higher in females than in males. The mammary glands of both sexes consisted of fine ducts with small end-buds and the glands of males contained mostly black pigments at any age examined. In either males or females, serum levels of prolactin and testosterone related little with age, DNA synthesizing enzyme activities or structure of the mammary glands. Furthermore, elevation by pituitary grafting of circulating prolactin affected neither DNA synthesizing enzyme activities nor structure of mammary glands in both sexes. The histological structures of adrenal, testis, ovary, ventral prostate and uterus of millardia were essentially similar to those of mice or rats.

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THE MATRIX OF PAIRWISE COMPARISONS OF SAMPLES IN THE ESTIMATION OF CHAOTIC DYNAMICS OF HEART RATE PARAMETERS IN YOUTH OF UGRA POPULATION FROM THE PERSPECTIVE OF AGE-RELATED CHANGES

Journal of New Medical Technologies eJournal ◽

10.12737/article_59439f3f731635.76565521 ◽

2017 ◽

pp. 1-1

Author(s):

Филатова ◽

D. Filatova ◽

Эльман ◽

Kseniya Elman ◽

Срыбник ◽

...

Keyword(s):

Heart Rate ◽

Chaotic Dynamics ◽

Pairwise Comparisons ◽

Age Related ◽

The Matrix ◽

Age Related Changes

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International relevance of Two Measures of Awareness of Age-Related Change (AARC)

10.21203/rs.3.rs-18586/v1 ◽

2020 ◽

Author(s):

Serena Sabatini ◽

Obioha C Ukoumunne ◽

Clive Ballard ◽

Allyson Brothers ◽

Roman Kaspar ◽

...

Keyword(s):

Cognitive Functioning ◽

Convergent Validity ◽

Demographic Variables ◽

Cognitive Health ◽

Age Related ◽

Males And Females ◽

University Degree ◽

Gains And Losses ◽

Functioning Subscale ◽

Age Related Changes

Abstract Background: A questionnaire assessing awareness of positive and negative age-related changes (AARC gains and losses) was developed in the US and Germany. We validated the short form of the measure (AARC-10 SF) and the cognitive functioning subscale from the 50-item version of the AARC (AARC-50) questionnaire in the UK population aged 50 and over.Methods: Data from 14,797 participants in the “blind for review” cohort were used to explore and confirm the psychometric properties of the AARC measures including: validity of the factor structure; reliability; measurement invariance across males and females and across individuals with and without a university degree; and convergent validity with measures of self-perception of aging and mental, physical, and cognitive health. We also explored the relationship between demographic variables and AARC.Results: We confirmed the two-factor structure (gains and losses) of the AARC-10 SF and the AARC-50 cognitive functioning subscale. Both scales showed good reliability and convergent validity. The meaning of AARC gains and losses was the same across males and females and across individuals with and without a university degree. Items composing AARC scales had the same meaning across individuals with and without a university degree. Items composing the AARC-50 cognitive functioning subscale had the same meaning across males and females. Two items in the AARC-10 SF had different meaning across males and females. Demographic variables significantly predicted AARC gains and losses.Conclusions: The AARC-10 SF and AARC-50 cognitive functioning subscale can help to identify UK individuals who perceive age-related changes in their mental, physical, and cognitive health.

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Sex-Specific Retinal Anomalies Induced by Chronic Social Defeat Stress in Mice

Frontiers in Behavioral Neuroscience ◽

10.3389/fnbeh.2021.714810 ◽

2021 ◽

Vol 15 ◽

Author(s):

Eric Arsenault ◽

Andrée-Anne Lavigne ◽

Samaneh Mansouri ◽

Anne-Marie Gagné ◽

Kimberley Francis ◽

...

Keyword(s):

Social Defeat ◽

Oscillatory Potentials ◽

Social Defeat Stress ◽

Major Depressive ◽

Retinal Activity ◽

Age Related ◽

Chronic Social Defeat Stress ◽

Before And After ◽

Males And Females ◽

Age Related Changes

Major depressive disorder (MDD) is one of the most common consequences of chronic stress. Still, there is currently no reliable biomarker to detect individuals at risk to develop the disease. Recently, the retina emerged as an effective way to investigate psychiatric disorders using the electroretinogram (ERG). In this study, cone and rod ERGs were performed in male and female C57BL/6 mice before and after chronic social defeat stress (CSDS). Mice were then divided as susceptible or resilient to stress. Our results suggest that CSDS reduces the amplitude of both oscillatory potentials and a-waves in the rods of resilient but not susceptible males. Similar effects were revealed following the analysis of the cone b-waves, which were faster after CSDS in resilient mice specifically. In females, rod ERGs revealed age-related changes with no change in cone ERGs. Finally, our analysis suggests that baseline ERG can predict with an efficacy up to 71% the expression of susceptibility and resilience before stress exposition in males and females. Overall, our findings suggest that retinal activity is a valid biomarker of stress response that could potentially serve as a tool to predict whether males and females will become susceptible or resilient when facing CSDS.

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