scholarly journals Glycosaminoglycans in the Human Cornea: Age-Related Changes

2015 ◽  
Vol 7 ◽  
pp. OED.S17204 ◽  
Author(s):  
Elena Pacella ◽  
Fernanda Pacella ◽  
Giulio De Paolis ◽  
Francesca Romana Parisella ◽  
Paolo Turchetti ◽  
...  

Aim To investigate possible age-related changes in glycosaminoglycans (GAGs) in the human cornea. The substances today called GAGs were previously referred to as mucopolysaccharides. Methods Samples of human cornea were taken from 12 younger (age 21 ± 1.2) and 12 older (age 72 ± 1.6) male subjects. Samples were weighed, homogenized, and used for biochemical and molecular analyses. All the quantitative results were statistically analyzed. Results The human cornea appears to undergo age-related changes, as evidenced by our biochemical and molecular results. The total GAG and hyaluronic acid counts were significantly higher in the younger subjects than in the older subjects. The sulfated heavy GAGs, such as chondroitin, dermatan, keratan, and heparan sulfate, were lower in the younger subjects than in the older subjects. Discussion GAGs of the human cornea undergo numerous age-related changes. Their quantity is significantly altered in the elderly in comparison with younger subjects. GAGs play an important role in age-related diseases of the human cornea.

2002 ◽  
Vol 93 (5) ◽  
pp. 1644-1649 ◽  
Author(s):  
Christopher T. Minson ◽  
Lacy A. Holowatz ◽  
Brett J. Wong ◽  
W. Larry Kenney ◽  
Brad W. Wilkins

Cutaneous vasodilation is reduced in healthy older vs. young subjects; however, the mechanisms that underlie these age-related changes are unclear. Our goal in the present study was to determine the role of nitric oxide (NO) and the axon reflexes in the skin blood flow (SkBF) response to local heating with advanced age. We placed two microdialysis fibers in the forearm skin of 10 young (Y; 22 ± 2 yr) and 10 older (O; 77 ± 5 yr) men and women. SkBF over each site was measured by laser-Doppler flowmetry (LDF; Moor DRT4). Both sites were heated to 42°C for ∼60 min while 10 mM N G-nitro-l-arginine methyl ester (l-NAME) was infused throughout the protocol to inhibit NO synthase (NOS) in one site and 10 mM l-NAME was infused after 40 min of local heating in the second site. Data were expressed as a percentage of maximal vasodilation (%CVCmax; 28 mM nitroprusside infusion). Local heating beforel-NAME infusion resulted in a significantly reduced initial peak (Y: 61 ± 2%CVCmax vs. O: 46 ± 4%CVCmax) and plateau (Y: 93 ± 2%CVCmaxvs. O: 82 ± 5%CVCmax) CVC values in older subjects ( P < 0.05). When NOS was inhibited after 40 min of heating, CVC declined to the same value in the young and older groups. Thus the overall contribution of NO to the plateau phase of the SkBF response to local heating was less in the older subjects. The initial peak response was significantly lower in the older subjects in both microdialysis sites (Y: 52 ± 4%CVCmax vs. O: 38 ± 5%CVCmax; P < 0.05). These data suggest that age-related changes in both axon reflex-mediated and NO-mediated vasodilation contribute to attenuated cutaneous vasodilator responses in the elderly.


Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
George Howard ◽  
Mary Cushman ◽  
Maciej Banach ◽  
Brett M Kissela ◽  
David C Goff ◽  
...  

Purpose: The importance of stroke research in the elderly is increasing as America is “graying.” For most risk factors for most diseases (including stroke), the magnitude of association with incident events decreases at older ages. Potential changes in the impact of risk factors could be a “true” effect, or could be due to methodological issues such as age-related changes in residual confounding. Methods: REGARDS followed 27,748 stroke-free participants age 45 and over for an average of 5.3 years, during which 715 incident strokes occurred. The association of the “Framingham” risk factors (hypertension [HTN], diabetes, smoking, AFib, LVH and heart disease) with incident stroke risk was assessed in age strata of 45-64 (Young), 65-74 (Middle), and 75+ (Old). For those with and without an “index” risk factor (e.g., HTN), the average number of “other” risk factors was calculated. Results: With the exception of AFib, there was a monotonic decrease in the magnitude of the impact across the age strata, with HTN, diabetes, smoking and LVH even becoming non-significant in the elderly (Figure 1). However, for most factors, the increasing prevalence of other risk factors with age impacts primarily those with the index risk factor absent (Figure 2, example HTN as the “index” risk factor). Discussion: The impact of stroke risk factors substantially declined at older ages. However, this decrease is partially attributable to increases in the prevalence of other risk factors among those without the index risk factor, as there was little change in the prevalence of other risk factors in those with the index risk factor. Hence, the impact of the index risk factor is attenuated by increased risk in the comparison group. If this phenomenon is active with latent risk factors, estimates from multivariable analysis will also decrease with age. A deeper understanding of age-related changes in the impact of risk factors is needed.


Gerontology ◽  
2017 ◽  
Vol 63 (6) ◽  
pp. 580-589 ◽  
Author(s):  
Juan Diego Naranjo ◽  
Jenna L. Dziki ◽  
Stephen F. Badylak

Sarcopenia is a complex and multifactorial disease that includes a decrease in the number, structure and physiology of muscle fibers, and age-related muscle mass loss, and is associated with loss of strength, increased frailty, and increased risk for fractures and falls. Treatment options are suboptimal and consist of exercise and nutrition as the cornerstone of therapy. Current treatment principles involve identification and modification of risk factors to prevent the disease, but these efforts are of limited value to the elderly individuals currently affected by sarcopenia. The development of new and effective therapies for sarcopenia is challenging. Potential therapies can target one or more of the proposed multiple etiologies such as the loss of regenerative capacity of muscle, age-related changes in the expression of signaling molecules such as growth hormone, IGF-1, myostatin, and other endocrine signaling molecules, and age-related changes in muscle physiology like denervation and mitochondrial dysfunction. The present paper reviews regenerative medicine strategies that seek to restore adequate skeletal muscle structure and function including exogenous delivery of cells and pharmacological therapies to induce myogenesis or reverse the physiologic changes that result in the disease. Approaches that modify the microenvironment to provide an environment conducive to reversal and mitigation of the disease represent a potential regenerative medicine approach that is discussed herein.


Blood ◽  
1988 ◽  
Vol 71 (6) ◽  
pp. 1726-1730
Author(s):  
KA Melez ◽  
LF Fries ◽  
BS Bender ◽  
T Quinn ◽  
MM Frank

Decreased immune functions have been suggested as a cause for the increased incidence of autoimmunity, malignancy, and infection in the elderly population. To assess the possible role of changes in macrophage function in the aging process we studied the Fc receptor- mediated clearance of IgG-coated erythrocytes in 56 healthy normal volunteers by following the removal of radiolabeled autologous erythrocytes. An age-related decrease in Fc-mediated clearance rates in both female and male subjects was found, which suggests a physiological decline of this macrophage function in older individuals.


1999 ◽  
Vol 89 (8) ◽  
pp. 383-391 ◽  
Author(s):  
W Lynch ◽  
J Mooney

A device was constructed to assess two-point discrimination in the plantar skin of younger, middle-aged, and older adults. The device consisted of paired filaments, each delivering a tip force of 4.56 log units (equivalent to 3.63 g), at a fixed distance apart. Statistical analysis showed significant differences in two-point discrimination accuracy between these groups of subjects. Younger subjects showed greater accuracy of plantar two-point discrimination than either middle-aged or older subjects, with an apparent inverse linear relationship between subject age and plantar two-point discrimination ability. A model to assess age-related changes in two-point discrimination is presented.


Author(s):  
Chen He ◽  
Wenzhen He ◽  
Jing Hou ◽  
Kaixuan Chen ◽  
Mei Huang ◽  
...  

Osteoporosis and sarcopenia are two age-related diseases that affect the quality of life in the elderly. Initially, they were thought to be two independent diseases; however, recently, increasing basic and clinical data suggest that skeletal muscle and bone are both spatially and metabolically connected. The term “osteosarcopenia” is used to define a condition of synergy of low bone mineral density with muscle atrophy and hypofunction. Bone and muscle cells secrete several factors, such as cytokines, myokines, and osteokines, into the circulation to influence the biological and pathological activities in local and distant organs and cells. Recent studies reveal that extracellular vesicles containing microRNAs derived from senescent skeletal muscle and bone cells can also be transported and aid in regulating bone-muscle crosstalk. In this review, we summarize the age-related changes in the secretome and extracellular vesicle-microRNAs secreted by the muscle and bone, and discuss their interactions between muscle and bone cells during aging.


2021 ◽  
Vol 35 (1) ◽  
pp. 60-66
Author(s):  
Nadezhda V. Bibikova ◽  
◽  
Liudmila N. Belonogova ◽  

The article highlights the problem of increasing the number of the elderly people and, as a consequence, the problem of ensuring vigorous activity and maintaining a healthy lifestyle. The authors of the article determine the potential of recreational activities for solving the social and psychological problems of the elderly. The article discusses the main definitions of the concepts of «recreation», «recreational activity», the characteristics of the socio-psychological characteristics. The article presents the results of an empirical study, during which the emotional state of the elderly, their sociopsychological adaptation and readiness to accept age-related changes were diagnosed. In addition, the article describes the results of the implemented program for organizing recreational activities with the elderly.


2013 ◽  
Vol 7 (1) ◽  
pp. 38-41 ◽  
Author(s):  
Demet Uçar ◽  
Demirhan Dıraçoğlu ◽  
Türker Süleyman ◽  
Nalan Çapan

Introduction: Osteoarthritis is the most common age-related degenerative joint disease. It affects all the joints containing hyaline cartilage. Knee osteoarthritis is the most cumbersome in terms of prevalence and disability. The aim of this study to evaluate the efficacy of intra-articular hyaluronic acid in patients with knee osteoarthritis with regard to joint pain and function, as well as patient satisfaction, assessed at one month and at one year, and by age group. Methods: In this prospective randomised study, 172 patients who were diagnosed knee OA and who received three consecutive intra-articular injections of HA weekly were included. Patients 65 years of age or older were accepted as the “elderly group”, and those under 65 were accepted as the “middle-aged group”. Clinical evaluations of efficacy and safety were conducted at the beginning of the study, one month after the third injection, and one year after the third injection. Results: In the two groups, the intragroup analysis revealed significant improvements following injection when compared with preinjection values. According to the last followup controls (after 12 months) in the middle-aged group, VAS activity pain, VAS rest pain, WOMAC physical function, and WOMAC pain values were found to be statistically lower when compared with pre-injection values. In the elderly group, no statistically significant differences were found between pre-injection and after 12 months. Conclusion: We can conclude that intra-articular joint HA injections are effective in both young and old patients with OA with regard to pain and functional status over a short-term period. Further, HA injections in patients younger than 65 years can be planned for a one-year period.


2012 ◽  
Vol 25 (0) ◽  
pp. 153
Author(s):  
Alex K. Malone ◽  
Nai-Yuan N. Chang ◽  
Timothy E. Hullar

Falls are one of the leading causes of disability in the elderly. Previous research has shown that falls may be related to changes in the temporal integration of multisensory stimuli. This study compared the temporal integration and processing of a vestibular and auditory stimulus in younger and older subjects. The vestibular stimulus consisted of a continuous sinusoidal rotational velocity delivered using a rotational chair and the auditory stimulus consisted of 5 ms of white noise presented dichotically through headphones (both at 0.5 Hz). Simultaneity was defined as perceiving the chair being at its furthest rightward or leftward trajectory at the same moment as the auditory stimulus was perceived in the contralateral ear. The temporal offset of the auditory stimulus was adjusted using a method of constant stimuli so that the auditory stimulus either led or lagged true simultaneity. 15 younger (ages 21–27) and 12 older (ages 63–89) healthy subjects were tested using a two alternative forced choice task to determine at what times they perceived the two stimuli as simultaneous. Younger subjects had a mean temporal binding window of 334 ± 37 ms (mean ± SEM) and a mean point of subjective simultaneity of 83 ± 15 ms. Older subjects had a mean TBW of 556 ± 36 ms and a mean point of subjective simultaneity of 158 ± 27. Both differences were significant indicating that older subjects have a wider temporal range over which they integrate vestibular and auditory stimuli than younger subjects. These findings were consistent upon retesting and were not due to differences in vestibular perception thresholds.


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