scholarly journals Dynamic Interactions Between LH and Testosterone in Healthy Community-Dwelling Men: Impact of Age and Body Composition

2019 ◽  
Vol 105 (3) ◽  
pp. e628-e641
Author(s):  
Ferdinand Roelfsema ◽  
Peter Y Liu ◽  
Paul Y Takahashi ◽  
Rebecca J Yang ◽  
Johannes D Veldhuis
Keyword(s):  
Body Composition ◽  
Leydig Cell ◽  
Approximate Entropy ◽  
Community Dwelling ◽  
High Dose ◽  
Dynamic Interactions ◽  
Visceral Mass ◽  
Age Related ◽  
The Difference ◽  
Healthy Community

Abstract Background Aging is associated with diminished testosterone (Te) secretion, which may be attributed to Leydig cell dysfunction, decreased pituitary stimulation, and altered Te feedback. Objective To study all regulatory nodes—gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and Leydig cell—in the same cohort of healthy men. Study Design This was a placebo-controlled, blinded, prospectively randomized cross-over study in 40 men, age range 19 to 73 years, and body mass index (BMI) range 20 to 34.3 kg/m2. A submaximal dose of the GnRH antagonist ganirelix was used to assess outflow of GnRH, by calculating the difference between LH output during the control arm and ganirelix arm. Ketoconazole (a steroidogenic inhibitor) was used to estimate feedback, by the difference in LH output during the ketoconazole and control arm. High-dose ganirelix and repeated LH infusions were used to measure testicular responsivity. Blood sampling was performed at 10-minute intervals. Results There were age-related, but not body composition–related decreases in estimated GnRH secretion, the feedback strength of Te on LH, and Leydig cell responsivity to LH, accompanied by changes in approximate entropy. Bioavailable Te levels were negatively related to both age and computed tomography (CT)–estimated abdominal visceral mass (AVF), without interaction between these variables. The LH response to a submaximal dose of GnRH was independent of age and AVF. Conclusion Advancing age is associated with (1) attenuated bioavailable Te secretion caused by diminished GnRH outflow and not by decreased GnRH responsivity of the gonadotrope, (2) diminished testicular responsivity to infused LH pulses, and (3) partial compensation by diminished Te feedback on central gonadotropic regulation.

scholarly journals OR32-04 Dynamic Interactions Between Luteinizing Hormone and Testosterone in Healthy Community-Dwelling Men: Impact by Age and Body Composition

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Ferdinand Roelfsema ◽  
Peter Y Liu ◽  
Paul Takahashi ◽  
Rebecca Yang ◽  
Johannes D Veldhuis
Keyword(s):  
Body Composition ◽  
Leydig Cell ◽  
Approximate Entropy ◽  
Research Unit ◽  
Community Dwelling ◽  
Blood Sampling ◽  
High Dose ◽  
Cell Axis ◽  
Deconvolution Analysis ◽  
The Difference

Abstract Context. Aging is associated with diminished testosterone (Te) secretion, which could be attributed to Leydig cell dysfunction, decreased pituitary stimulation and altered Te feedback. Objective. The goal was to quantify all three regulatory nodes of the GnRH-LH-Leydig cell- axis in the same cohort of healthy men, by measuring (1) indirectly the strength of the endogenous GnRH signal on the gonadotrope, (2) the strength of Te feedback on LH by ketoconazole (KTCZ), and (3) the effect of LH infusions on Te secretion, in relation to age and body composition. Design. This was a placebo-controlled, blinded, prospectively randomized cross-over study in 40 men, age 19–73 yr, BMI 20–34.3 kg/m2. A submaximal dose of ganirelix (GnRH antagonist) was used to assess outflow of GnRH, by calculating the difference between LH output during the control and ganirelix arm. Ketoconazole (steroidogenic inhibitor) was used to estimate feedback, by the difference in LH output during ketoconazole and control arm. High-dose ganirelix and repeated 6-min LH (18.75 IU) infusions were used to measure testicular responsivity. Blood sampling was at 10-min intervals. The 4 sessions were concluded with, a single submaximally GnRH stimulus to assess the responsiveness of the gonadotrope during ganirelix inhibition. Setting. The study was performed in a Clinical Translational Research Unit. Interventions. In 3 of the 4 experiments subjects underwent 5 h of blood sampling at 10-min intervals, starting at 0800 h. At 1100 h GnRH was injected and sampling was continued for another 2 h. Admission was at 1700 h the day before. At 2000 h they received KTCZ, dexamethasone or ganirelix and/or placebo. KTCZ and dexamethasone (or placebo) were administered again at 0700 when the IV catheter was placed. High-dose ganirelix was used to test the testicular responsiveness, and 7 LH pulses (90 min intervals) were given., with blood sampling from 1500 till 1300 h next day. Outcome measures. Mean concentrations of LH and (bio)Te, deconvolution analysis, endogenous dose-response LH-bioTe relation, and approximate entropy. Abdominal visceral fat (AVF) was calculated from single slice CT. Results. There were age-, but not body composition-related decreases in estimated endogenous GnRH secretion, Te’s feedback strength on LH, and Leydig cell responsivity to LH, accompanied by changes in approximate entropy. Bioavailable Te levels were negatively related to both age and AVF, without interaction between these variables. The LH response to a submaximal dose of GnRH was independent of age and AVF. Conclusion. Advancing age is associated with 1) attenuated bioavailable Te secretion caused by diminished GnRH outflow and not by decreased GnRH responsivity of the gonadotrope, 2) diminished testicular responsivity to infused LH pulses, and 3) partial compensation by diminished Te feedback on central gonadotropic regulation.

scholarly journals Pet Ownership and Longitudinal Change in Physical Function: Evidence From the BLSA

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 216-217
Author(s):  
Erika Friedmann ◽  
Nancy Gee ◽  
Eleanor Simonsick ◽  
Erik Barr ◽  
Barbara Resnick ◽  
...  
Keyword(s):  
Gait Speed ◽  
Successful Aging ◽  
Leisure Time Physical Activity ◽  
Psychological Adaptation ◽  
Community Dwelling ◽  
Longitudinal Change ◽  
Pet Ownership ◽  
Age Related ◽  
Animal Interaction ◽  
Healthy Community

Abstract Successful aging depends on avoiding disease and disability, maintaining high physical and cognitive function, and psychological adaptation. Research examining the relationship of pet ownership (PO) or human-animal interaction (HAI) to human health supports contributions to these successful ag-ing-related outcomes at some point in the life-cycle, mostly in populations with diseases or disabili-ties. We examine the contributions of PO to maintaining physical capacity among generally healthy community-dwelling older participants in the Baltimore Longitudinal Study of Aging (BLSA). Partici-pants’ [N=637, mean age=68.3 years (SD=9.6), pet owners N=149] completed a standardized physi-cal function test battery (among other measures) every 1-4 years and a ten-year PO history. Linear mixed, or generalized linear mixed, models with time varying PO were used to examine change in successful aging-related outcomes over up to 13 years [mean=7.5, (SD=3.6)] according to PO. Physi-cal function declined across all domains examined, but was observed to be less severe with PO in overall physical performance (p<0.001), rapid gait speed (p=0.041), 400-meter walk time (p<0.001), and reported physical wellbeing (p=0.032). No differences were observed for grip strength (p=0.56), usual gait speed (p=0.07), and leisure time physical activity (p=0.26) after con-trolling for age. This study provides the first longitudinal evidence that PO may promote successful aging among community-dwelling healthy older adults by moderating age-related declines in physical functional status in late-life.

Age-Related Changes in the Neurologic Examination of Healthy Sexagenarians, Octogenarians, and Centenarians

1994 ◽  
Vol 7 (1) ◽  
pp. 1-7 ◽  
Author(s):  
M.E. Nichols ◽  
K.J. Meador ◽  
D.W. Loring ◽  
L.W. Poon ◽  
G.M. Clayton ◽  
...  
Keyword(s):  
Population Based ◽  
Cognitive Status ◽  
Community Dwelling ◽  
Neurologic Examination ◽  
Geriatric Population ◽  
Age Related ◽  
Quantitative Examination ◽  
Healthy Community ◽  
Future Population ◽  
Age Related Changes

Although numerous studies have focused on age-related changes in the nervous system, few have systematically assessed global neurologic examination changes, and even fewer have included the most elderly population, ie, the centenarians. To perform such a study, we developed a quantitative assessment that includes the major components of a standard bedside neurologic evaluation, with special emphasis on cognitive function. First, we demonstrated that the quantitated examination could correctly classify healthy controls and patients with stroke or dementia based on discriminant analysis. This examination was then applied to healthy community-dwelling elderly ranging from 60 to 108 years of age. Significant age-related neurobehavioral changes were apparent across even these most “successfully” aged groups. Analysis of the full pattern of cognitive and neurologic findings provided the most accurate assessment. Pathologic reflexes, reportedly associated with normal aging, occurred infrequently in this healthy geriatric population, suggesting that age-related changes in the neurologic examination may be more accurately interpreted when assessed in conjunction with cognitive status. This quantitative examination may be useful in future population-based studies of neurologic function in the aged.

scholarly journals 3-Hydroxyanthranilic acid Administration Did Not Prevent Age Related Bone Loss

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 680-681
Author(s):  
Carlos Isales ◽  
Ke-Hong Ding ◽  
Wendy Bollag ◽  
Meghan McGee-Lawrence ◽  
William Hill ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Body Composition ◽  
Bone Loss ◽  
Bone Mineral ◽  
Degradation Products ◽  
High Dose ◽  
Mineral Density ◽  
Tryptophan Degradation ◽  
Age Related ◽  
Hydroxyanthranilic Acid

Abstract Aging is associated with accumulation of various tryptophan degradation products that may having either bone anabolic or catabolic effects. In epidemiologic studies, elevated levels of 3-hydroxyanthranilic acid (3-HAA) are associated with a higher bone mineral density (BMD). We have previously shown that the C57BL/6 mouse loses bone mass with age. Thus, we hypothesized that administering 3-HAA via a daily intraperitoneal (IP) injection would result in preserved or increased BMD. In an IACUC-approved protocol, we injected 26-month-old C57BL/6 mice with either a low dose (0.5 mg) or high dose (5 mg) of 3-HAA IP five days a week for eight weeks. At the end of this time mice were sacrificed and body composition and bone mineral density measured by DigiMus. BMD was significantly lower in the high dose 3-HAA group: 0.0570 + 0.004 vs 0.0473 + 0.006 vs 0.0432 + 0.0075 gm/cm2, (means+SD, Control vs 0.5 mg 3HAA vs 5 mg 3HAA, p=0.004, 0 vs 5.0 mg, n=6-9/group). 3-HAA had no significant impact on body composition (lean body mass: 86.7 + 1.7% vs 86.2 + 2.7% vs 86.1 + 2.0%, Control vs 0.5 mg vs 5.0 mg 3-HAA, p=ns; and fat mass 12.6 + 2.0% vs 13.8 + 2.7% vs 13.9 + 2.0% vs 0.2%, Control vs 0.5 vs 5 mg 3-HAA, p=ns). Thus, 3-HAA did not prevent bone loss in older mice but instead significantly worsened bone loss. 3-HAA is known to have both pro- and anti- oxidant effects depending on the environment. These data would suggest that at the higher concentrations 3-HAA is acting predominantly as a pro-oxidant molecule accelerating age-related bone loss.

scholarly journals Lifestyle Activities and Memory: Variety May Be the Spice of Life. The Women's Health and Aging Study II

2011 ◽  
Vol 18 (2) ◽  
pp. 286-294 ◽  
Author(s):  
Michelle C. Carlson ◽  
Jeanine M. Parisi ◽  
Jin Xia ◽  
Qian-Li Xue ◽  
George W. Rebok ◽  
...  
Keyword(s):  
Verbal Memory ◽  
Cognitive Abilities ◽  
Cognitive Aging ◽  
Community Dwelling ◽  
Cognitive Outcomes ◽  
Age Related ◽  
Aging Study ◽  
Cognitive Challenge ◽  
Lifestyle Activities ◽  
Healthy Community

AbstractThis study examined whether participation in a variety of lifestyle activities was comparable to frequent participation in cognitively challenging activities in mitigating impairments in cognitive abilities susceptible to aging in healthy, community-dwelling older women. Frequencies of participation in various lifestyle activities on the Lifestyle Activities Questionnaire (LAQ) were divided according to high (e.g., reading), moderate (e.g., discussing politics), and low (e.g., watching television) cognitive demand. We also considered the utility of participation in a variety of lifestyle activities regardless of cognitive challenge. Immediate and delayed verbal recall, psychomotor speed, and executive function were each measured at baseline and at five successive exams, spanning a 9.5-year interval. Greater variety of participation in activities, regardless of cognitive challenge, was associated with an 8 to 11% reduction in the risk of impairment in verbal memory and global cognitive outcomes. Participation in a variety of lifestyle activities was more predictive than frequency or level of cognitive challenge for significant reductions in risk of incident impairment on measures sensitive to cognitive aging and risk for dementia. Our findings offer new perspectives in promoting a diverse repertoire of activities to mitigate age-related cognitive declines. (JINS, 2012, 18, 286–294)

scholarly journals Finding Factors in Footfalls: Exploring the Factor Structure of Gait in Older Adults

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 657-657
Author(s):  
Michael Willden ◽  
Josh Palmer ◽  
Kristina Kowalski ◽  
Sandra Hundza ◽  
Stuart MacDonald
Keyword(s):  
Factor Structure ◽  
A Priori ◽  
Principal Component ◽  
Optimal Number ◽  
Community Dwelling ◽  
Gait Performance ◽  
Age Related ◽  
Number Of Factors ◽  
Using Data ◽  
Healthy Community

Abstract Gait is a reputed marker of global health spanning various bodily systems (MacDonald et al., 2017) and is a robust predictor of deleterious age-related outcomes (Van Kan et al., 2009). However, the sheer number of individual gait variables employed as predictors in the existing literature can obscure interpretations. To address this issue, researchers have explored the factor structure of gait indicators to explain variance in age-related gait performance, identifying disparate models characterized by three to five underlying latent gait constructs comprised of 8 to 23 indicators (Hollman et al., 2011; Lord et al., 2013). Beyond this heterogeneity, additional limitations characterizing this literature include solutions that assume statistical independence among gait constructs, as well as inclusion of severely multicollinear indicators. Using data from the Healthy Minds Healthy Bodies (HMHB) study, the present research focused upon replicating and contrasting previous factor analytic efforts. HMHB participants (n=128) were healthy community-dwelling adults (Mage=72.81±5.24 years; female=100). Gait indicators from a GAITRite computerized walkway were selected according to a priori theoretical rationale, compatibility with previous studies, and consideration of multicollinearity. Gait factor structure was initially analyzed using principal component analysis. Results indicate the presence of three latent gait domains reflecting pace, rhythm, and variability, accounting for over 82.4% of the variance in gait performance. Current proceedings involve implementing confirmatory factor analysis to compare competing gait models. Findings will address disparities across factor models in the gait literature, as well as discuss the optimal number of factors for describing the underlying dimensionality of gait.

scholarly journals RAMBLE ON: LONELINESS AND OFF-TOPIC VERBOSITY IN OLDER ADULTS

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S531-S531
Author(s):  
Leah N Smith ◽  
Jessica H Helphrey ◽  
Jennifer Sawyer ◽  
Leigh A Fierro ◽  
Ben K Mokhtari ◽  
...  
Keyword(s):  
Older Adults ◽  
Social Relationships ◽  
Procedural Memory ◽  
Community Dwelling ◽  
Communication Style ◽  
Younger Adults ◽  
Age Related ◽  
Adult Participants ◽  
Healthy Community ◽  
The Relationship

Abstract Numerous studies have found off-topic verbosity occurs more frequently in older adults than younger adults. Previous theories have attributed this to age-related decline, emotion recognition, and communication style. Previous research has linked lower loneliness with more off-topic verbosity; however, the precise nature of this relationship remains unclear. Loneliness has been defined as an inconsistency between an individual’s actual and desired social relationships, and previous research has found that loneliness is associated with lower cognitive and social outcomes among diverse populations including older adults. The purpose of this study was to investigate the relationship between loneliness and off-topic verbosity among older adults. Healthy, community dwelling older adult participants (N = 82; age 60-99, M = 76.66, SD = 8.52) completed the Three-Item Loneliness Scale and provided a verbal sample in which they recounted an autobiographical memory (a vacation) and a procedural memory (how to make a breakfast); the verbal samples were transcribed and rated by three independent judges. In contrast with previous research, results found that loneliness was associated with a greater tendency to engage in tangential verbal topics. This suggests that social factors such as loneliness may impact the way some older adults express themselves verbally.

Physical Activity Intervention Studies and Their Relationship to Body Composition in Healthy Women

2013 ◽  
Vol 31 (1) ◽  
pp. 71-142 ◽  
Author(s):  
Susan Weber Buchholz ◽  
JoEllen Wilbur ◽  
Shannon Halloway ◽  
Judith H. McDevitt ◽  
Michael E. Schoeny
Keyword(s):  
Physical Activity ◽  
Body Composition ◽  
Randomized Clinical Trials ◽  
Physical Activity Intervention ◽  
Overweight And Obesity ◽  
Community Dwelling ◽  
Healthy Weight ◽  
Physically Active ◽  
Physical Activity Interventions ◽  
Healthy Community

Engaging in regular physical activity is a key component for maintaining a healthy weight and preventing overweight and obesity. Obesity continues to be a concern globally, especially for women, and women are less physically active than men. This systematic review examined current research on physical activity interventions designed for healthy community dwelling women and assessed the effects of those interventions on physical activity and body composition. Three author-developed data collection tools were used to extract and examine study variables. For studies with suitable data, effect sizes were obtained. The initial search identified 1,406 titles published between 2000 and 2012, of which 40 randomized clinical trials met inclusion criteria. Of these 40 studies, 16 had a physical activity intervention that did not have a diet component and 24 had a physical activity intervention along with a diet component. The overall weighted mean effect was

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