Age-related Histological Changes Research Articles

A machine learning approach for quantifying age-related histological changes in the mouse kidney

The ability to quantify aging-related changes in histological samples is important, as it allows for evaluation of interventions intended to effect health span. We used a machine learning architecture that can be trained to detect and quantify these changes in the mouse kidney. Using additional held out data, we show validation of our model, correlation with scores given by pathologists using the Geropathology Research Network aging grading scheme, and its application in providing reproducible and quantifiable age scores for histological samples. Aging quantification also provides the insights into possible changes in image appearance that are independent of specific geropathology-specified lesions. Furthermore, we provide trained classifiers for H&E-stained slides, as well as tutorials on how to use these and how to create additional classifiers for other histological stains and tissues using our architecture. This architecture and combined resources allow for the high throughput quantification of mouse aging studies in general and specifically applicable to kidney tissues.

Age-Related Histologic and Biochemical Changes in Auricular and Nasal Cartilages.

Analyze age-related changes in histologic features and biochemical properties of human auricular cartilage and two subsites of nasal cartilages (quadrangular cartilage and dorsal septal articulation with upper lateral cartilages). Prospective cross-sectional study of nasal and auricular cartilages from seventy-three (73) live donors. Auricular cartilage (AC), quadrangular cartilage (QC), and dorsal septal cartilage articulation (DSA) with the upper lateral cartilage (ULCs) were collected intraoperatively. Histochemical staining was used: Safranin O for glycosaminoglycans (GAGs), Verhoeff's for elastin, and Masson's trichrome for collagen. ImageJ2 software was used to calculate cell count and percent stained for each cartilage type. R studio "ggplot" package was used to visualize age versus cell count or percent stained. Participant ages ranged from 20 to 77 years, average 46.5 years. There was a significant decline in GAGs with age for the DSA subsite, (n = 64, p < 0.001). Significant increase in collagen content with age was observed for DSA subsite (n = 66, p < 0.001) and the QC subsite (n = 64, p < 0.05). There was a statistically insignificant decline in elastin with age (n = 41, p = 0.309) for AC. Cell count declined with age at all cartilage subsites. Our findings confirm that there were age-related decreases in cartilage glycosaminoglycan content, and chondrocyte cell count in both auricular and nasal cartilages. We have also confirmed that collagen content increases with age for both auricular and nasal cartilage. The histologic findings while not statistically significant in all comparisons, provides additional evidence that there is some loss of structural integrity and flexibility in nasal and auricular cartilage with aging. NA Laryngoscope, 134:1220-1226, 2024.

Possible role of locus coeruleus neuronal loss in age-related memory and attention deficits.

Aging is associated with a decline in cognitive abilities, including memory and attention. It is generally accepted that age-related histological changes such as increased neuroinflammatory glial activity and a reduction in the number of specific neuronal populations contribute to cognitive aging. Noradrenergic neurons in the locus coeruleus (LC) undergo an approximately 20 % loss during ageing both in humans and mice, but whether this change contributes to cognitive deficits is not known. To address this issue, we asked whether a similar loss of LC neurons in young animals as observed in aged animals impairs memory and attention, cognitive domains that are both influenced by the noradrenergic system and impaired in aging. For that, we treated young healthy mice with DSP-4, a toxin that specifically kills LC noradrenergic neurons. We compared the performance of DSP-4 treated young mice with the performance of aged mice in models of attention and memory. To do this, we first determined the dose of DSP-4, which causes a similar 20 % neuronal loss as is typical in aged animals. Young mice treated with DSP-4 showed impaired attention in the presence of distractor and memory deficits in the 5-choice serial reaction time test (5-CSRTT). Old, untreated mice showed severe deficits in both the 5-CSRTT and in fear extinction tests. Our data now suggest that a reduction in the number of LC neurons contributes to impaired working memory and greater distractibility in attentional tasks but not to deficits in fear extinction. We hypothesize that the moderate loss of LC noradrenergic neurons during aging contributes to attention deficits and working memory impairments.

Dynamic Changes in the Endocannabinoid System during the Aging Process: Focus on the Middle-Age Crisis.

Endocannabinoid (eCB) signaling is markedly decreased in the hippocampus (Hip) of aged mice, and the genetic deletion of the cannabinoid receptor type 1 (CB1) leads to an early onset of cognitive decline and age-related histological changes in the brain. Thus, it is hypothesized that cognitive aging is modulated by eCB signaling through CB1. In the present study, we detailed the changes in the eCB system during the aging process using different complementary techniques in mouse brains of five different age groups, ranging from adolescence to old age. Our findings indicate that the eCB system is most strongly affected in middle-aged mice (between 9 and 12 months of age) in a brain region-specific manner. We show that 2-arachidonoylglycerol (2-AG) was prominently decreased in the Hip and moderately in caudate putamen (CPu), whereas anandamide (AEA) was decreased in both CPu and medial prefrontal cortex along with cingulate cortex (mPFC+Cg), starting from 6 months until 12 months. Consistent with the changes in 2-AG, the 2-AG synthesizing enzyme diacylglycerol lipase α (DAGLα) was also prominently decreased across the sub-regions of the Hip. Interestingly, we found a transient increase in CB1 immunoreactivity across the sub-regions of the Hip at 9 months, a plausible compensation for reduced 2-AG, which ultimately decreased strongly at 12 months. Furthermore, quantitative autoradiography of CB1 revealed that [3H]CP55940 binding markedly increased in the Hip at 9 months. However, unlike the protein levels, CB1 binding density did not drop strongly at 12 months and at old age. Furthermore, [3H]CP55940 binding was significantly increased in the lateral entorhinal cortex (LEnt), starting from the middle age until the old age. Altogether, our findings clearly indicate a middle-age crisis in the eCB system, which could be a potential time window for therapeutic interventions to abrogate the course of cognitive aging.

AGE‐RELATED CHANGES IN THE STRUCTURE OF THE CAVOTRICUSPID ISTHMUS IN AN EAST AFRICAN POPULATION

The cavotricuspid isthmus (CTI) is a concave, quadrilateral region of the right atrium between the ostium of the inferior vena cava (IVC) and the tricuspid valve (TV). Three levels of the isthmus have been described from supero‐medial to inferolateral aspects as para‐septal, central and inferolateral isthmus. Antero‐posteriorly, the CTI is also described in three sectors; posterior, middle and anterior sectors, with variable morphologies. The CTI is a common site for atrial flutter (AFL) macro‐reentrant circuits and its histological structure, dimensions and proximity to the right coronary artery (RCA) and minor coronary vein (MCV) are the key determinants of both the occurrences as well as success of management of these AFL. Interestingly, both the prevalence as well as post‐ablation complications of AFL are higher in elderly populations, suggesting possible age‐related histological and morphometric changes in the CTI. Despite this possibility, age‐related histomorphological changes of the CTI are yet to be described. Thus, this study’s objective was to determine the age‐related changes in the structure of the CTI by testing the hypothesis that there are age‐related changes in the structure of the CTI.40 morphologically normal hearts with intact CTI were obtained from post‐mortem heart specimens at Chiromo Funeral Parlor and Kenyatta National Hospital Mortuary following ethical approval by the Kenyatta National Hospital ‐ University of Nairobi Ethical Review Commission. Subjects were classified according to 4 age groups; &lt;20, 21‐35, 36‐50, &gt;50. This study used vertical inter‐caval incisions on the posterior aspect of the right atrium. The gross appearance of the CTI sectors was determined as either trabeculated/membranous/recessed. Additionally, light microscopy and histology were used to identify myocardial architecture. Means and standard deviations of linear measurements were calculated and correlated for heart weight. Gross morphology and histo‐architecture were presented in photo‐macrographs and photomicrographs. Results demonstrate that myocardial thickness and proximity of the RCA to the endocardium increased among the 0‐20 to 21‐35 age groups, but reduced in the 36‐50 and &gt;50. The distance of the MCV from the endocardium increased with age but dropped in the &gt;50 age group. Moreover, an increase in age is correlated with an increase in sub‐Eustachian recess prevalence, prevalence of a trabeculated posterior sector, a combination of trabeculae bridges, ridges and intra‐trabeculae recesses within the middle sector. These findings suggest that thinning of the myocardium as well as the increase in heterogeneity of trabeculations, associated with an increase in age, are the structural basis behind the high prevalence of AFL among the elderly. Furthermore, the close proximity of minor coronary veins to the endocardium and the high prevalence of sub‐Eustachian recess may account for the difficulties during ablation and recurrence of AFL post‐ablation associated with advancement in age.

Age-related histological changes in rat tibia.

At present, studies on osteochondral morphogenesis only focus on a certain period of time or only provide a pattern diagram, but lack of dynamic tracking observation from the initiation of development to maturity. This study was aimed to dynamically observe the changes of skeleton morphology and structure from embryo to adult, to provide research data for enriching the knowledge of bone and cartilage tissue structure. In the intrauterine experiment, 5 normal pregnant Wistar rats were sacrificed under anaesthesia at gestational day (GD) 14, 17, 20, respectively. One of their offspring was randomly selected, and a total of 5 offspring were obtained at each time point. In the postnatal experiment, on the 7th and 10th day after birth and at postnatal weeks (PW) 2, 3, 6, 12, 28, 5 offspring rats from 5 different pregnant Wistar rats were randomly selected and sacrificed under anaesthesia at each time point. After obtaining the above offspring, the soft tissue was removed, and the tibia of hind limbs was retained for paraffin-embedded section. After stained with Safranin-O-fast-green and haematoxylin, the morphological development of the tibia was observed under an optical microscope. At GD14, there was no obvious joint space, the whole hind limb was cartilage and bone tissue was not visible. At GD17, visible joint space was seen and the chondrocytes in the centre region appeared to hypertrophy. At GD20, the primary ossification centre was obvious, and a typical epiphysis growth plate structure could be seen. On the 7th day after birth, the chondrocytes in the centre of epiphysis cartilage were hypertrophic and differentiated, the cartilage canal grows from the cartilage surface toward the centre of the epiphysis cartilage, at postnatal day 14, the secondary ossification centre was formed. At this time, the tibia had typical morphological characteristics of the metaphysis, however, there was no obvious layered structure of articular cartilage; the stratified structure of articular cartilage could be seen at PW6, but its mature marker (tidemark) was still not visible; however, at PW12, typical 4 layers of articular cartilage appeared, and the tidemark was visible. The growth plates were clearly visible at PW2, 6 and 12. At PW28, growth plates could still be observed, but its morphology is abnormal. Our results, for the first time, dynamically observed the morphological changes of osteochondral at critical period of development from embryo to adult, especially the process of cartilage canal participating in the formation of secondary ossification centre.

Histological and biomechanical properties of systemic arteries in young and old Warmblood horses.

Arterial rupture is a well-recognized cause of sudden death in horses, which mainly affects older horses. The arterial wall is known to stiffen with age, although the underlying age-related histological and biomechanical changes remain unclear. The purpose of this study was to investigate the effect of aging by histological analysis of the arterial wall and examination of the arterial wall biomechanical properties using an inflation-extension test. Entire circular samples of the proximal and distal aorta, cranial and caudal common carotid, external iliac, femoral and median artery were collected from 6 young (6 years) and 14 old horses (≥15 years). Samples of all arteries were histologically examined and intima media thickness as well as area % of elastin, smooth muscle actin and collagen type I and III were determined. Older horses had a significantly larger intima media thickness and a significantly higher area % of smooth muscle actin compared to young horses. Samples of the proximal and distal aorta, the caudal common carotid and the external iliac artery were mechanically assessed using an in-house developed inflation-extension device with ultrasound analysis. Rupture occurred in a minority of arteries (8/78) at high pressures (between 250–300 mmHg), and mostly occurred in older horses (7/8). Pressure-area, pressure-compliance and pressure-distensibility curves were constructed. A significant difference in the pressure-area curves of the distal aorta, common carotid artery and external iliac artery, the pressure-compliance curves of the proximal aorta and carotid artery and the pressure-distensibility curve of the proximal aorta was observed between young and old horses. Results demonstrate an effect of age on the histological and biomechanical properties of the arterial wall, which might explain why arterial rupture occurs more often in older horses.

Age-related Histological Changes in the Renal Telocytes in Male Albino Rats

Background:Many researches on telocytes (TCs) have proved its exis­tence, structure and specific immune markers expression in many normal organs and in different species. Multiple physiologic functions have been suggested for these cells. Objectives: This study is designed to evaluate age-related changes ofTCs in different age groups in the renal tissue. Materials and Methods: 18 male Sprague- Dawley rats were used in this study and divided equally into 3 groups (each consists of 6 rats); Group I (rats aged 3 weeks), Group II (rats aged 3 months, adult) and Group III (rats aged one year). All rats of group I, II and III were sacrificed and each group was divided into two subgroups. The first subgroup was processed for light microscopic and immunohistochemical staining. The second subgroup was processed for electron microscopy. Morphometric and statistical studies were conducted. Results: TCs with their characteristic long and thin cytoplasmic projections (telopodes, Tps) are detected in each of H&E stained and CD34 immunostained sections. In group III, there is a significant reduction of the TCs count. TEM examination of the ultrathin sections revealed shrinkage of TCs with disintegration and fragmentation of the Tps with a significant reduction of the number of Tps arising from each TC in group III. In all groups of the study, homocellular and heterocellular junctions are observed. Conclusion: On comparison of the age groups in the study, it is proved that TCs decrease in number with degenerative changes observed with aging.

Age-related biochemical and histological changes in the soleus muscle of male mice

During aging, skeletal muscle is subjected to progressiveloss of muscle mass and strength (sarcopenia) and a decline in thefunctional ability. The reduction in the antioxidative capacity ofthe skeletal muscle resulting in an abnormal accumulation of thereactive oxygen species (ROS) that is one of the possible causesof the decline in muscle performance. In this study thehistological changes in the soleus muscles of male mice at the ageof 1st and 15th old were examined and the activities of theantioxidant enzymes, CAT and SOD, non- enzymatic antioxidantGPH and MDA level were measured to clarify the age-relatedchanges in healthy subjects. Results showed that there is asignificant reduction (P ≤ 0.05) in the antioxidants SOD, CATand GPH and there is a significant increase (P ≤ 0.05) in MDAlevel at the age of 15th month when compared to 1st month old.We concluded that the activities of the antioxidants were affectedby aging. Moreover, there is age- related lipid peroxidation.

Age-related histological changes in calcified cartilage and subchondral bone in femoral heads from healthy humans.

Age is the most important risk factor for osteoarthritis (OA). It is suggested that changes in subchondral bone and calcified cartilage may occur in early OA. Therefore, the aim was to investigate age-related changes in the femoral head composition. We hypothesise that the thickness of the subchondral bone plate decreases with age, while the thickness of the calcified cartilage increases with age as seen in early-stage OA. Femoral heads from 29 women (20-74 years) and 32 men (23-78 years), who had died suddenly and unexpectedly, were obtained at autopsy. Individuals with bone or joint diseases or macroscopic abnormal cartilage were excluded. Using design-based stereology, femoral head volume as well as thickness and volume of the calcified cartilage and subchondral bone plate were estimated and correlated to sex and age. The thickness and volume of the subchondral bone plate were not correlated with age. Calcified cartilage thickness and volume correlated positively with age in women, while the femoral head volume was correlated positively with age in men. In human femoral heads obtained from a cross-sectional population without macroscopic OA changes, the thickness of the subchondral bone plate did not change with age, which differs from the thinning seen in early OA. Surprisingly, the age-related changes of the volume and thickness of the calcified cartilage and of the volume of the femoral head were different for women and men. This indicate that cartilage and bone metabolism is sex-specific, which may influence ageing of the hip joint.

Morphological and Functional Changes in the Thyroid Follicles of the Aged Murine and Humans.

BackgroundAlthough both thyroid histology and serum concentrations of hormones are known to change with age, only a few reports exist on the relationship between the age-related structural and functional changes of the thyroid follicles in both mice and humans. Our objectives were to investigate age-related histological changes of the thyroid follicles and to determine whether these morphological changes were associated with the functional activity of the follicles.MethodsThe thyroid glands of mice at 18 weeks and at 6, 15, and 30 months of age were histologically examined, and the serum levels of thyroid hormones were measured in 11-week-old and 20-month-old mice. Samples of human thyroid tissue from 10 women over 70 years old and 10 women between 30 and 50 years of age were analyzed in conjunction with serum thyroid hormone level.ResultsThe histological and functional changes observed in the thyroid follicles of aged mice and women were as follows: variable sizing and enlargement of the follicles; increased irregularity of follicles; Sanderson’s polsters in the wall of large follicles; a large thyroglobulin (Tg) globule or numerous small fragmented Tg globules in follicular lumens; oncocytic change in follicular cells; and markedly dilated follicles empty of colloid. Serum T3 levels in 20-month-old mice and humans were unremarkable.ConclusionsThyroid follicles of aged mice and women show characteristic morphological changes, such as cystic atrophy, empty colloid, and Tg globules.

Age related histological changes in rat kidney

Histological changes in rat kidney associated with growth and aging were assessed from day one after delivery to thirty months of age. Growth was associated with increase in body and total kidney weight. Different parts of nephron showed an increase in size with growth. In aging rats there was compensatory hypertrophy of renal corpuscle, focal atrophy of proximal and distal convoluted tubules with intra tubular cast and cellular infiltration.

Chapter 20 - Aging of the auditory system

Presbycusis or age-related hearing loss (ARHL) affects most elderly people. It is characterized by reduced hearing thresholds and speech understanding with the well-known negative consequences for communication and quality of social life. The hearing loss is connected to age-related histologic changes, as described and classified by Schuknecht. Aging itself is a multifactorial, genetically driven process that is influenced by oxidative stress that gradually leads to reduced endocochlear potential and cell loss of key players in sound transmission and supporting structures. Oxidative stress is caused by damaging factors like noise, infection, and other systemic factors. All reparative mechanisms in acute and chronic cochlear damage attempt to reduce oxidative stress and to balance inner-ear homeostasis. Accurate clinical assessment of ARHL starts with the differentiation between peripheral and central components. Treatment of the peripheral hearing loss often involves hearing aids, whereas auditory and psychologic training seems to be important in central auditory disturbance.

The effect of coenzyme Q10 on age-related changes of the distal colon mucosa of male albino rats

Introduction Aging is associated with a number of diverse effects on the colon leading to deterioration in its functions. The reactive oxygen species have been suggested as an important factor in aging. Coenzyme Q10 (CoQ10) is a vitamin-like substance, endogenously synthesized inside the cell. It serves as an antioxidant. CoQ10 decreases gradually with aging. Aim of Work The aim of this study was to evaluate the role of CoQ10 in age-related histological changes of the distal colon of male albino rats. Materials and methods A total of 20 male albino rats were used in this study. The rats were divided into three groups: group I, group II, and group III. Group I comprised 10 rats aged 4±1 months, which served as the control group. Group II (the aged group) comprised five rats aged 18±1 months. Group III comprised five rats of similar age as that of group II and received CoQ10 daily through the intraperitoneal route at a dose of 5 mg/kg body weight/day for 8 weeks. Specimens of the distal colon were excised and paraffin sections were prepared for histological and immunohistochemical staining. Results In aged rats (group II), the mucosa showed discontinuity and loss of surface epithelium with increased intraepithelial lymphocytes. There was significant decrease in the number of PAS-positive (periodic acid Schiff) goblet cells, with abnormal proliferation within the crypt. Intense immunopositive stain for tumor necrosis factor-α was detected in the mucosa. Extensive mononuclear cellular infiltration was eminent within the lamina propria. Significant increase in collagen fibers was detected in the lamina propria of the distal colon. In group III, the mucosa appeared intact with minimal cellular infiltration. PAS-positive goblet cells were nearly similar to those of controls. Immunopositive reaction for tumor necrosis factor-α was significantly decreased compared with group II. Significant decrease in collagen fiber content was seen in the lamina propria. Conclusion The administration of CoQ10 improved age-related histological changes that occurred in the distal colon of rats.

Treatment of aging vocal folds: novel approaches.

This article aims to review previous research reports and to summarize current strategies for the treatment of the aging vocal fold using regenerative medicine and tissue engineering, with a particular focus on growth factor therapy. Previous studies have elucidated age-related histological and gene expression changes in key extracellular matrix components, such as collagen and hyaluronan, in the lamina propria of the aging vocal fold. On the basis of these findings, our research group has focused on growth factor therapy to restore extracellular matrix distribution in the aging vocal fold to a younger state. Results from recent studies with basic fibroblast growth factor and hepatocyte growth factor provided preliminary evidence of the regenerative effects of growth factor therapy on treatment of the aging vocal fold. In addition, a clinical trial using basic fibroblast growth factor revealed improvements of maximum phonation time, mean flow rate, and acoustic parameters in atrophied vocal folds. These positive findings suggest that the administration of basic fibroblast growth factor may become a useful tool for the treatment of the aging vocal fold. Regenerative medicine and tissue engineering are innovative strategies for the treatment of aging vocal folds, and recent reports have also confirmed the therapeutic potential of growth factor therapy for the treatment of the aging vocal fold. More recently, the clinical application of basic fibroblast growth factor was reported with encouraging outcomes. Continued basic research and clinical investigations will be required to develop strategies to overcome age-related voice disorders.

Age-related Changes in the Articular Cartilage of the Stifle Joint in Non-working and Working German Shepherd Dogs

The aims of this study were to define age-related histological changes in the articular cartilage of the stifle joint in non-chondrodystrophic dogs and to determine whether physical activity has a positive impact on preservation of cartilage structure during ageing. Twenty-eight German shepherd dogs were included in the study. These dogs had no evidence of joint inflammation as defined by clinical assessment, radiology and synovial fluid analysis (specifically absence of synovial fluid serum amyloid A). The dogs were grouped as young working (n ¼ 4), young non-working (n ¼ 5), aged working (n ¼ 13) and aged non-working (n ¼ 6) animals. Gross changes in the stifle joints were recorded and biopsy samples of femoral and tibial articular cartilage were evaluated for thickness; chondrocyte number, density, surface area and morphology; isogenous group morphology; tidemark integrity; subchondral bone structure; presence of proteoglycans/ glycosaminoglycans; and expression of type I, II and X collagens. The major age-related changes, not related to type of physical activity, included elevated chondrocyte density and thinning of tibial cartilage and increased chondrocyte surface area in the superficial and intermediate zone of the femoral cartilage. There was also expression of type X collagen in the femoral and tibial calcified and non-calcified cartilage; however, type X collagen was not detected in the superficial zone of old working dogs. Therefore, ageing, with or without physical activity, leads to slight cartilage degeneration, while physical activity modulates the synthesis of type X collagen in the superficial cartilage zone, partially preserving the structure of hyaline cartilage.

Quantitative histological analysis and ultrastructure of the aging human testis

To quantitatively assess the histological and ultrastructural changes resulting from aging in the human testis. Age-related histological and ultrastructural changes were evaluated using light microscopy, transmission electron microscopy (TEM) and immunohistochemistry on 41 testicular samples obtained from elderly men and, respectively, assigned to group A (n = 20), 54-69 years old or group B (n = 21), 70-89 years old. Testicular samples derived from 17 young men were used for control. The numbers of Sertoli cells in the aged groups were significantly lower than that in the controls (p < 0.05). With the exception of the Sertoli cell ratios (germ cells/Sertoli cells) of spermatogonia and primary spermatocytes, results showed lower levels of the Sertoli cell ratios of round spermatids and elongated spermatids in the elderly men compared with the young men (p < 0.05). A similar degenerative pattern of the organelles was shown in germ cells and Sertoli cells in the aging testes under TEM. Immunohistochemistry revealed an increased apoptosis index (AI) (0.81 ± 0.13) accompanied by a decreased proliferation index (PI) (30.08 ± 4.86) in the group B (p < 0.05), while both AI and PI were similar between the group A (0.54 ± 0.06; 36.38 ± 7.38) and the controls (0.50 ± 0.15; 40.55 ± 7.92) (p > 0.05). Aging has negative influence on testicular morphology and spermatogenesis, and the failure of spermatogenic cell development is evident from the spermatid level.

Age-Related Histological Changes in Kidneys of Brown Norway Rat

ABSTRACTIn this study, age-dependent histological changes in the kidneys of Brown Norway rat, a strain useful for conducting aging research, were evaluated. Examination was performed at 3, 12, 18, 24 and 30 months of age. Sclerotic and hypertrophic changes of the glomeruli were observed, and quantitative scores of these changes persistently increased with age. A marginal increase in scores was observed for glomerular cystic changes and tubulointerstitial damage. Further, urothelial hyperplasia was observed in the renal papillae, particularly at 30 months of age. In conclusion, the findings of the present study demonstrate that the Brown Norway strain exhibits persistent, but mild progression of age-dependent renal histological changes.

Age-related histological and zinc content changes in adult nonhyperplastic prostate glands

To clarify age-related histological and Zn content changes in nonhyperplastic adult prostate glands, a quantitative morphometric and energy-dispersive X-ray fluorescence analyses were performed. The prostates were obtained from autopsies of 63 subjects aged 21-70 years who died mainly from trauma. It was found that histologically normal prostate tissue undergoes substantial changes throughout aging. These changes are reflected in an increase of the percent volume of the glandular lumen for the third to fifth decades, reaching a maximum for the decade 41-50 years. Over the same period, the percent volume of the stroma remains steady, but the percent volume of epithelium decreases, approximately, linearly with age. The percent volume of glandular lumen (reflects the volume of prostatic fluid) in the prostate gland of men aged 41 to 50 years is 1.5-fold higher than that in men aged 21 to 30 years, but the epithelium/lumen (prostatic fluid) ratio is approximately twofold lower. This suggests that accumulation of the prostatic fluid develops from 30 to 50 years of age. This accumulation of the prostatic fluid results in an increase of the Zn mass fraction in the prostate. In turn, when the intraprostatic Zn level exceeds a certain level by the end of the fifth decade, it begins to work as a trigger for different factors, all of which increase the proliferation of stromal cells. Deductions from these results allow possible partial explanations of both relevant prostatic aging mechanisms and the effects of dietary interventions using supplementary Zn.

Original article The neuroprotective effect of long-term n-3 polyunsaturated fatty acids supplementation in the cerebral cortex and hippocampus of aging rats

The purpose of this study was to determine whether hippocampus and cerebral cortex fatty acids (FA) composition can be altered as a result of n-3 enriched diet, or modifications in FA can affect the age-related histological changes in these brain tissues. The study was performed on eighteen rats which were fed control (CD) or fish oil supplemented diet (FOD) for 12 months. We investigated the n-3 and n-6 brain FA profile by gas-chromatography analysis. Histomorphometry included the measurement of the quantity of pyramidal cells in the cerebral cortex (layer II-III) and in the hippocampal formation (CA1, CA3 and DG). The number of apoptotic cells (neuron and glial cells) was also calculated separately in three hippocampal areas and in the pyramidal cerebral cortex layer. Rats fed supplemented diet showed a significantly poorer content of the arachidonic acid (AA, 20:4n6) in all brain regions when compared to the control group. Furthermore, the level of the docosahexaenoic acid (DHA, 22:6n3) was significantly higher in the cerebral cortex in fish oil fed rats vs. the control group. The neurons of the pyramidal cortex showed significant changes in cell density in control animals when compared to the group of fish oil fed rats. Furthermore, the number of positive apoptotic cells was significantly higher in the CA1 area and cerebral pyramidal layer in rats fed control diet. Following dietary n-3 fatty acids supplementation, the increase in DHA content in the cerebral cortex resulted in consequential changes in histology of this tissue. The results obtained indicate that dietary intake of fish n-3 fatty acids may reduce the risk of age-related brain impairments.