Live Attenuated Leishmania donovani Centrin Knock Out Parasites Generate Non-inferior Protective Immune Response in Aged Mice against Visceral Leishmaniasis.

PubMed

Bhattacharya, Parna; Dey, Ranadhir; Dagur, Pradeep K; Joshi, Amritanshu B; Ismail, Nevien; Gannavaram, Sreenivas; Debrabant, Alain; Akue, Adovi D; KuKuruga, Mark A; Selvapandiyan, Angamuthu; McCoy, John Philip; Nakhasi, Hira L

2016-08-01

Visceral leishmaniasis (VL) caused by the protozoan parasite Leishmania donovani causes severe disease. Age appears to be critical in determining the clinical outcome of VL and at present there is no effective vaccine available against VL for any age group. Previously, we showed that genetically modified live attenuated L. donovani parasites (LdCen-/-) induced a strong protective innate and adaptive immune response in young mice. In this study we analyzed LdCen-/- parasite mediated modulation of innate and adaptive immune response in aged mice (18 months) and compared to young (2 months) mice. Analysis of innate immune response in bone marrow derived dendritic cells (BMDCs) from both young and aged mice upon infection with LdCen-/- parasites, showed significant enhancement of innate effector responses, which consequently augmented CD4+ Th1 cell effector function compared to LdWT infected BMDCs in vitro. Similarly, parasitized splenic dendritic cells from LdCen-/- infected young and aged mice also revealed induction of proinflammatory cytokines (IL-12, IL-6, IFN-γ and TNF) and subsequent down regulation of anti-inflammatory cytokine (IL-10) genes compared to LdWT infected mice. We also evaluated in vivo protection of the LdCen-/- immunized young and aged mice against virulent L. donovani challenge. Immunization with LdCen-/- induced higher IgG2a antibodies, lymphoproliferative response, pro- and anti-inflammatory cytokine responses and stimulated splenocytes for heightened leishmanicidal activity associated with nitric oxide production in young and aged mice. Furthermore, upon virulent L. donovani challenge, LdCen-/- immunized mice from both age groups displayed multifunctional Th1-type CD4 and cytotoxic CD8 T cells correlating to a significantly reduced parasite burden in the spleen and liver compared to naïve mice. It is interesting to note that even though there was no difference in the LdCen-/- induced innate response in dendritic cells between aged and young

Aging-associated renal disease in mice is fructokinase dependent.

PubMed

Roncal-Jimenez, Carlos A; Ishimoto, Takuji; Lanaspa, Miguel A; Milagres, Tamara; Hernando, Ana Andres; Jensen, Thomas; Miyazaki, Makoto; Doke, Tomohito; Hayasaki, Takahiro; Nakagawa, Takahiko; Marumaya, Shoichi; Long, David A; Garcia, Gabriela E; Kuwabara, Masanari; Sánchez-Lozada, Laura G; Kang, Duk-Hee; Johnson, Richard J

2016-10-01

Aging-associated kidney disease is usually considered a degenerative process associated with aging. Recently, it has been shown that animals can produce fructose endogenously, and that this can be a mechanism for causing kidney damage in diabetic nephropathy and in association with recurrent dehydration. We therefore hypothesized that low-level metabolism of endogenous fructose might play a role in aging-associated kidney disease. Wild-type and fructokinase knockout mice were fed a normal diet for 2 yr that had minimal (<5%) fructose content. At the end of 2 yr, wild-type mice showed elevations in systolic blood pressure, mild albuminuria, and glomerular changes with mesangial matrix expansion, variable mesangiolysis, and segmental thrombi. The renal injury was amplified by provision of high-salt diet for 3 wk, as noted by the presence of glomerular hypertrophy, mesangial matrix expansion, and alpha smooth muscle actin expression, and with segmental thrombi. Fructokinase knockout mice were protected from renal injury both at baseline and after high salt intake (3 wk) compared with wild-type mice. This was associated with higher levels of active (phosphorylated serine 1177) endothelial nitric oxide synthase in their kidneys. These studies suggest that aging-associated renal disease might be due to activation of specific metabolic pathways that could theoretically be targeted therapeutically, and raise the hypothesis that aging-associated renal injury may represent a disease process as opposed to normal age-related degeneration.

The effect of aging on efferent nerve fibers regeneration in mice.

PubMed

Verdú, E; Butí, M; Navarro, X

1995-10-23

This study evaluates the influence of aging on nerve regeneration and reinnervation of target organs in mice aged 2, 6, 9, 12, 18 and 24 months. In animals of each age group the sciatic nerve was subjected to crush, section or section and suture. Reinnervation of plantar muscles and sweat glands (SG) was evaluated over three months after operation by functional methods. Reappearance of SG secretion and motor responses occurred slightly earlier in young than older mice. The degree of motor and sudomotor reinnervation, with respect to preoperative control values, was also significantly higher in young than old animals. The differences were more pronounced after 12 months of age. The degree of recovery progressively decreased with the severity of the lesion, differences being more marked in older mice. Neurorraphy improved recovery, comparatively more in older than in young mice. These results indicate that, after injuries of peripheral nerves, axonal regeneration and reinnervation are maintained throughout life, but tend to be more delayed and slightly less effective with aging.

Memory Deficits Are Associated with Impaired Ability to Modulate Neuronal Excitability in Middle-Aged Mice

ERIC Educational Resources Information Center

Kaczorowski, Catherine C.; Disterhoft, John F.

2009-01-01

Normal aging disrupts hippocampal neuroplasticity and learning and memory. Aging deficits were exposed in a subset (30%) of middle-aged mice that performed below criterion on a hippocampal-dependent contextual fear conditioning task. Basal neuronal excitability was comparable in middle-aged and young mice, but learning-related modulation of the…

Proteomic analysis of specific brain proteins in aged SAMP8 mice treated with alpha-lipoic acid: implications for aging and age-related neurodegenerative disorders.

PubMed

Poon, H Fai; Farr, Susan A; Thongboonkerd, Visith; Lynn, Bert C; Banks, William A; Morley, John E; Klein, Jon B; Butterfield, D Allan

2005-01-01

Free radical-mediated damage to neuronal membrane components has been implicated in the etiology of Alzheimer's disease (AD) and aging. The senescence accelerated prone mouse strain 8 (SAMP8) exhibits age-related deterioration in memory and learning along with increased oxidative markers. Therefore, SAMP8 is a suitable model to study brain aging and, since aging is the major risk factor for AD and SAMP8 exhibits many of the biochemical findings of AD, perhaps as a model for and the early phase of AD. Our previous studies reported higher oxidative stress markers in brains of 12-month-old SAMP8 mice when compared to that of 4-month-old SAMP8 mice. Further, we have previously shown that injecting the mice with alpha-lipoic acid (LA) reversed brain lipid peroxidation, protein oxidation, as well as the learning and memory impairments in SAMP8 mice. Recently, we reported the use of proteomics to identify proteins that are expressed differently and/or modified oxidatively in aged SAMP8 brains. In order to understand how LA reverses the learning and memory deficits of aged SAMP8 mice, in the current study, we used proteomics to compare the expression levels and specific carbonyl levels of proteins in brains from 12-month-old SAMP8 mice treated or not treated with LA. We found that the expressions of the three brain proteins (neurofilament triplet L protein, alpha-enolase, and ubiquitous mitochondrial creatine kinase) were increased significantly and that the specific carbonyl levels of the three brain proteins (lactate dehydrogenase B, dihydropyrimidinase-like protein 2, and alpha-enolase) were significantly decreased in the aged SAMP8 mice treated with LA. These findings suggest that the improved learning and memory observed in LA-injected SAMP8 mice may be related to the restoration of the normal condition of specific proteins in aged SAMP8 mouse brain. Moreover, our current study implicates neurofilament triplet L protein, alpha-enolase, ubiquitous mitochondrial

Effects of social isolation, re-socialization and age on cognitive and aggressive behaviors of Kunming mice and BALB/c mice.

PubMed

An, Dong; Chen, Wei; Yu, De-Qin; Wang, Shi-Wei; Yu, Wei-Zhi; Xu, Hong; Wang, Dong-Mei; Zhao, Dan; Sun, Yi-Ping; Wu, Jun-Cheng; Tang, Yi-Yuan; Yin, Sheng-Ming

2017-05-01

Both Kunming (KM) mice and BALB/c mice have been widely used as rodent models to investigate stress-associated mental diseases. However, little is known about the different behaviors of KM mice and BALB/c mice after social isolation, particularly cognitive and aggressive behaviors. In this study, the behaviors of KM and BALB/c mice isolated for 2, 4 and 8 weeks and age-matched controls were evaluated using object recognition, object location and resident-intruder tests. The recovery of behavioral deficits by re-socialization was also examined for the isolated mice in adolescence. Our study showed that isolation for 2, 4 and 8 weeks led to cognitive deficits and increased aggressiveness for both KM and BALB/c mice. An important finding is that re-socialization could completely recover spatial/non-spatial cognitive deficits resulted from social isolation for both KM and BALB/c mice. In addition, age only impacted aggressiveness of KM mice. Moreover, isolation duration showed different impacts on cognitive and aggressive behaviors for both KM and BALB/c mice. Furthermore, BALB/c mice showed weak spatial/non-spatial memory and low aggressiveness when they were at the same age and isolation duration, compared to KM mice. In conclusion, KM mice and BALB/c mice behaved characteristically under physiology and isolation conditions. © 2016 Japanese Society of Animal Science.

Live Attenuated Leishmania donovani Centrin Knock Out Parasites Generate Non-inferior Protective Immune Response in Aged Mice against Visceral Leishmaniasis

PubMed Central

Bhattacharya, Parna; Dey, Ranadhir; Dagur, Pradeep K.; Joshi, Amritanshu B.; Ismail, Nevien; Gannavaram, Sreenivas; Debrabant, Alain; Akue, Adovi D.; KuKuruga, Mark A.; Selvapandiyan, Angamuthu; McCoy, John Philip; Nakhasi, Hira L.

2016-01-01

Background Visceral leishmaniasis (VL) caused by the protozoan parasite Leishmania donovani causes severe disease. Age appears to be critical in determining the clinical outcome of VL and at present there is no effective vaccine available against VL for any age group. Previously, we showed that genetically modified live attenuated L. donovani parasites (LdCen-/-) induced a strong protective innate and adaptive immune response in young mice. In this study we analyzed LdCen-/- parasite mediated modulation of innate and adaptive immune response in aged mice (18 months) and compared to young (2 months) mice. Methodology Analysis of innate immune response in bone marrow derived dendritic cells (BMDCs) from both young and aged mice upon infection with LdCen-/- parasites, showed significant enhancement of innate effector responses, which consequently augmented CD4+ Th1 cell effector function compared to LdWT infected BMDCs in vitro. Similarly, parasitized splenic dendritic cells from LdCen-/- infected young and aged mice also revealed induction of proinflammatory cytokines (IL-12, IL-6, IFN-γ and TNF) and subsequent down regulation of anti-inflammatory cytokine (IL-10) genes compared to LdWT infected mice. We also evaluated in vivo protection of the LdCen-/- immunized young and aged mice against virulent L. donovani challenge. Immunization with LdCen-/- induced higher IgG2a antibodies, lymphoproliferative response, pro- and anti-inflammatory cytokine responses and stimulated splenocytes for heightened leishmanicidal activity associated with nitric oxide production in young and aged mice. Furthermore, upon virulent L. donovani challenge, LdCen-/- immunized mice from both age groups displayed multifunctional Th1-type CD4 and cytotoxic CD8 T cells correlating to a significantly reduced parasite burden in the spleen and liver compared to naïve mice. It is interesting to note that even though there was no difference in the LdCen-/- induced innate response in dendritic cells

Collagen VI Null Mice as a Model for Early Onset Muscle Decline in Aging

PubMed Central

Capitanio, Daniele; Moriggi, Manuela; De Palma, Sara; Bizzotto, Dario; Molon, Sibilla; Torretta, Enrica; Fania, Chiara; Bonaldo, Paolo; Gelfi, Cecilia; Braghetta, Paola

2017-01-01

Collagen VI is an extracellular matrix (ECM) protein playing a key role in skeletal muscles and whose deficiency leads to connective tissue diseases in humans and in animal models. However, most studies have been focused on skeletal muscle features. We performed an extensive proteomic profiling in two skeletal muscles (diaphragm and gastrocnemius) of wild-type and collagen VI null (Col6a1−/−) mice at different ages, from 6- (adult) to 12- (aged) month-old to 24 (old) month-old. While in wild-type animals the number of proteins and the level of modification occurring during aging were comparable in the two analyzed muscles, Col6a1−/− mice displayed a number of muscle-type specific variations. In particular, gastrocnemius displayed a limited number of dysregulated proteins in adult mice, while in aged muscles the modifications were more pronounced in terms of number and level. In diaphragm, the differences displayed by 6-month-old Col6a1−/− mice were more pronounced compared to wild-type mice and persisted at 12 months of age. In adult Col6a1−/− mice, the major variations were found in the enzymes belonging to the glycolytic pathway and the tricarboxylic acid (TCA) cycle, as well as in autophagy-related proteins. When compared to wild-type animals Col6a1−/− mice displayed a general metabolic rewiring which was particularly prominent the diaphragm at 6 months of age. Comparison of the proteomic features and the molecular analysis of metabolic and autophagic pathways in adult and aged Col6a1−/− diaphragm indicated that the effects of aging, culminating in lipotoxicity and autophagic impairment, were already present at 6 months of age. Conversely, the effects of aging in Col6a1−/− gastrocnemius were similar but delayed becoming apparent at 12 months of age. A similar metabolic rewiring and autophagic impairment was found in the diaphragm of 24-month-old wild-type mice, confirming that fatty acid synthase (FASN) increment and decreased

Lycopersicon esculentum Extract Enhances Cognitive Function and Hippocampal Neurogenesis in Aged Mice

PubMed Central

Bae, Jung-Soo; Han, Mira; Shin, Hee Soon; Shon, Dong-Hwa; Lee, Soon-Tae; Shin, Chang-Yup; Lee, Yuri; Lee, Dong Hun; Chung, Jin Ho

2016-01-01

A decrease in adult neurogenesis is associated with the aging process, and this decrease is closely related to memory impairment. Tomato (Lycopersicon esculentum) is a fruit with diverse bioactive nutrients that is consumed worldwide. In this study, we investigated the cognition-enhancing effect of tomato ethanolic extracts (TEE) in aged mice. Six weeks of oral TEE administration in 12-month-old aged mice significantly increased their exploration time of novel objects when compared to vehicle-treated mice. The TEE supplement increased doublecortin (DCX)-positive cells and postsynaptic density-95 (PSD95) expression in mice hippocampus. Moreover, we found an increased expression of brain-derived neurotrophic factor (BDNF) and subsequently-activated extracellular-signal-regulated kinase (ERK)/cAMP response element binding (CREB) signaling pathway in the TEE-supplemented mice hippocampus. In conclusion, the oral administration of TEE exhibits a cognition-enhancing effect, and the putative underlying mechanism is the induction of BDNF signaling-mediated proliferation and synapse formation in the hippocampus. These findings indicate that TEE could be a candidate for treatment of age-related memory impairment and neurodegenerative disorders. PMID:27792185

Lycopersicon esculentum Extract Enhances Cognitive Function and Hippocampal Neurogenesis in Aged Mice.

PubMed

Bae, Jung-Soo; Han, Mira; Shin, Hee Soon; Shon, Dong-Hwa; Lee, Soon-Tae; Shin, Chang-Yup; Lee, Yuri; Lee, Dong Hun; Chung, Jin Ho

2016-10-26

A decrease in adult neurogenesis is associated with the aging process, and this decrease is closely related to memory impairment. Tomato ( Lycopersicon esculentum ) is a fruit with diverse bioactive nutrients that is consumed worldwide. In this study, we investigated the cognition-enhancing effect of tomato ethanolic extracts (TEE) in aged mice. Six weeks of oral TEE administration in 12-month-old aged mice significantly increased their exploration time of novel objects when compared to vehicle-treated mice. The TEE supplement increased doublecortin (DCX)-positive cells and postsynaptic density-95 (PSD95) expression in mice hippocampus. Moreover, we found an increased expression of brain-derived neurotrophic factor (BDNF) and subsequently-activated extracellular-signal-regulated kinase (ERK)/cAMP response element binding (CREB) signaling pathway in the TEE-supplemented mice hippocampus. In conclusion, the oral administration of TEE exhibits a cognition-enhancing effect, and the putative underlying mechanism is the induction of BDNF signaling-mediated proliferation and synapse formation in the hippocampus. These findings indicate that TEE could be a candidate for treatment of age-related memory impairment and neurodegenerative disorders.

Sex-specific phenotypes of hyperthyroidism and hypothyroidism in aged mice.

PubMed

Rakov, Helena; Engels, Kathrin; Hönes, Georg Sebastian; Brix, Klaudia; Köhrle, Josef; Moeller, Lars Christian; Zwanziger, Denise; Führer, Dagmar

2017-12-22

Sex and age play a role in the prevalence of thyroid dysfunction (TD), but their interrelationship for manifestation of hyper- and hypothyroidism is still not well understood. Using a murine model, we asked whether sex impacts the phenotypes of hyper- and hypothyroidism at two life stages. Hyper- and hypothyroidism were induced by i.p. T4 or MMI/ClO 4 -/LoI treatment over 7 weeks in 12- and 20-months-old female and male C57BL/6N mice. Control animals underwent PBS treatment (n = 7-11 animals/sex/treatment). Animals were investigated for impact of sex on body weight, food and water intake, body temperature, heart rate, behaviour (locomotor activity, motor coordination and strength) and serum thyroid hormone (TH) status. Distinct sex impact was found in eu- and hyperthyroid mice, while phenotypic traits of hypothyroidism were similar in male and female mice. No sex difference was found in TH status of euthyroid mice; however, T4 treatment resulted in twofold higher TT4, FT4 and FT3 serum concentrations in adult and old females compared to male animals. Hyperthyroid females consistently showed higher locomotor activity and better coordination but more impairment of muscle function by TH excess at adult age. Importantly and in contrast to male mice, adult and old hyperthyroid female mice showed increased body weight. Higher body temperature in female mice was confirmed in all age groups. No sex impact was found on heart rate irrespective of TH status in adult and old mice. By comparison of male and female mice with TD at two life stages, we found that sex modulates TH action in an organ- and function-specific manner. Sex differences were more pronounced under hyperthyroid conditions. Importantly, sex-specific differences in features of TD in adult and old mice were not conclusively explained by serum TH status in mice.

Age, experience and genetic background influence treadmill walking in mice

PubMed Central

Wooley, Christine M.; Xing, Shuqin; Burgess, Robert W.; Cox, Gregory A.; Seburn, Kevin L.

2009-01-01

WOOLEY, C.M., S. XING, R.W. BURGESS, G.A. COX, AND K.L. SEBURN. Age, experience and genetic background influence treadmill walking in mice. PHYSIOL. BEHAV. XX(X), XXX-XXX, 2008 – The use of a treadmill to gather data for gait analysis in mice is a convenient, sensitive method to evaluate motor performance. However, evidence from several species, including mice, shows that treadmill locomotion is a novel task that is not equivalent to over ground locomotion and that may be particularly sensitive to the test environment and protocol. We investigated the effects of age, genetic background and repeated trials on treadmill walking in mice and show that these factors are important considerations in the interpretation of gait data. Specifically we report that as C57BL/6J (B6) mice age, the animals use progressively longer, less frequent strides to maintain the same walking speed. The increase is most rapid between 1 and 6 months of age and is explained, in part, by changes in size and weight. We also extended previous findings showing that repeat trials cause mice to modify their treadmill gait pattern. In general, B6 mice tend to take shorter, more frequent steps and adopt a wider dynamic stance with repeated walking trials. The nature and extent of the response changes with both the number and timing of the trials and was observed with inter-trial intervals as long as 3 months. Finally, we compared the gait pattern of an additional seven inbred strains of mice and found significant variation in the length and frequency of strides used to maintain the same walking speed. The combined results offer the bases for further mechanistic studies and can be used to guide optimal experimental design. PMID:19027767

Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging.

PubMed

Ghosh, Amiya K; O'Brien, Martin; Mau, Theresa; Yung, Raymond

2017-09-07

Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation.

Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging

PubMed Central

Ghosh, Amiya K.; O'Brien, Martin; Mau, Theresa; Yung, Raymond

2017-01-01

Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation. PMID:28898202

RADIATION INDUCED AGING IN MICE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtis, H.J.; Gebhard, K.L.

1958-10-31

. Experiments were undertaken in an effort to determine the degree of similarity between natural and radiation induced aging, and to determine the causes for the latter. Several severe non-specific stresses were applied to mice either as single massive doses or as smaller doses administered over a large fraction of the life span of the animals. Stresses used included typhoid vaccine, tetanus toxin and tetanus toxoid and turpentine. None of these produced any premature aging comparable to that produced by radiation. The somatic mutation theory of aging and expecially radiationinduced aging has been tested by applying the chemical mutatgen, nitrogenmore » mustard, either as a massive single dose or as smaller single doses repeated over long periods of time. No shortening of the life span has been observed and it is concluded that the somatic mutation theory is untenable. Experiments designed to determine the organ system responsible for radiation induced aging have demonstrated that the hematopoietic system is not primarily involved in this phenomenon. (auth)« less

Age-Related Decrease in Stress Responsiveness and Proactive Coping in Male Mice.

PubMed

Oh, Hee-Jin; Song, Minah; Kim, Young Ki; Bae, Jae Ryong; Cha, Seung-Yun; Bae, Ji Young; Kim, Yeongmin; You, Minsu; Lee, Younpyo; Shim, Jieun; Maeng, Sungho

2018-01-01

Coping is a strategic approach to dealing with stressful situations. Those who use proactive coping strategies tend to accept changes and act before changes are expected. In contrast, those who use reactive coping are less flexible and more likely to act in response to changes. However, little research has assessed how coping style changes with age. This study investigated age-related changes in coping strategies and stress responsiveness and the influence of age on the processing of conditioned fear memory in 2-, 12- and 23-month-old male mice. Coping strategy was measured by comparing the escape latency in an active avoidance test and by comparing responses to a shock prod. The results showed that proactivity in coping response gradually decreased with age. Stress responsiveness, measured by stress-induced concentration of corticosterone, was also highest in 2-month-old mice and decreased with age. Consolidation of fear memory was highest in 12-month-old mice and was negatively correlated with the degree of stress responsiveness and proactivity in coping. Fear extinction did not differ among age groups and was not correlated with stress responsiveness or the proactivity of coping. However, the maintenance of extinct fear memory, which was best in 2-month-old mice and worst in 12-month-old mice, was negatively correlated with stress responsiveness but not with coping style. Age-dependent changes in the expression of glucocorticoid receptor (GR) and its regulatory co-chaperones, which are accepted mechanisms for stress hormone stimulation, were measured in the hippocampus. The expression of GR was increased at 12 months compared to other age groups. There were no differences in Hsp70 and BAG1 expression by age. These results can be summarized as follows: (1) stress responsiveness and proactivity in coping decreased with age class; (2) consolidation of fear memory was negatively correlated with both stress responsiveness and proactivity; however, maintenance of

Age-Related Decrease in Stress Responsiveness and Proactive Coping in Male Mice

PubMed Central

Oh, Hee-Jin; Song, Minah; Kim, Young Ki; Bae, Jae Ryong; Cha, Seung-Yun; Bae, Ji Young; Kim, Yeongmin; You, Minsu; Lee, Younpyo; Shim, Jieun; Maeng, Sungho

2018-01-01

Coping is a strategic approach to dealing with stressful situations. Those who use proactive coping strategies tend to accept changes and act before changes are expected. In contrast, those who use reactive coping are less flexible and more likely to act in response to changes. However, little research has assessed how coping style changes with age. This study investigated age-related changes in coping strategies and stress responsiveness and the influence of age on the processing of conditioned fear memory in 2-, 12- and 23-month-old male mice. Coping strategy was measured by comparing the escape latency in an active avoidance test and by comparing responses to a shock prod. The results showed that proactivity in coping response gradually decreased with age. Stress responsiveness, measured by stress-induced concentration of corticosterone, was also highest in 2-month-old mice and decreased with age. Consolidation of fear memory was highest in 12-month-old mice and was negatively correlated with the degree of stress responsiveness and proactivity in coping. Fear extinction did not differ among age groups and was not correlated with stress responsiveness or the proactivity of coping. However, the maintenance of extinct fear memory, which was best in 2-month-old mice and worst in 12-month-old mice, was negatively correlated with stress responsiveness but not with coping style. Age-dependent changes in the expression of glucocorticoid receptor (GR) and its regulatory co-chaperones, which are accepted mechanisms for stress hormone stimulation, were measured in the hippocampus. The expression of GR was increased at 12 months compared to other age groups. There were no differences in Hsp70 and BAG1 expression by age. These results can be summarized as follows: (1) stress responsiveness and proactivity in coping decreased with age class; (2) consolidation of fear memory was negatively correlated with both stress responsiveness and proactivity; however, maintenance of

Mid-aged and aged wild-type and progestin receptor knockout (PRKO) mice demonstrate rapid progesterone and 3alpha,5alpha-THP-facilitated lordosis.

PubMed

Frye, C A; Sumida, K; Lydon, J P; O'Malley, B W; Pfaff, D W

2006-05-01

Progesterone (P) and its 5alpha-reduced metabolite, 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP), facilitate sexual behavior of rodents via agonist-like actions at intracellular progestin receptors (PRs) and membrane GABA(A)/benzodiazepine receptor complexes (GBRs), respectively. Given that ovarian secretion of progestins declines with aging, whether or not senescent mice are responsive to progestins was of interest. Homozygous PR knockout (PRKO) or wild-type mice that were between 10-12 (mid-aged) or 20-24 (aged) months of age were administered P or 3alpha,5alpha-THP, and the effect on lordosis were examined. Effects of a progestin-priming regimen that enhances PR-mediated (experiment 1) or more rapid, PR-independent effects of progestins (experiments 2 and 3) on sexual behavior were examined. Levels of P, 3alpha,5alpha-THP, and muscimol binding were examined in tissues from aged mice (experiment 4). Wild-type, but not PRKO, mice were responsive when primed with 17beta-estradiol (E(2); 0.5 microg) and administered P (500 microg, subcutaneously). Mid-aged wild-type mice demonstrated greater increases in lordosis 6 h later compared to their pre-P, baseline test than did aged wild-type mice (experiment 1). Lordosis of younger and older wild-type, but not PRKO, mice was significantly increased within 5 min of intravenous (IV) administration of P (100 ng), compared with E(2)-priming alone (experiment 2). However, wild-type and PRKO mice demonstrated significant increases in lordosis 5 min after IV administration of 3alpha,5alpha-THP, an effect which was more pronounced in mid-aged than in aged animals (100 ng-experiment 3). In tissues from aged wild-type and PRKO mice, levels of P, 3alpha,5alpha-THP, and muscimol binding were increased by P administration (experiment 4). PR binding was lower in the cortex of PRKO than that of wild-type mice. Mid-aged and aged PRKO and wild-type mice demonstrated rapid P or 3alpha,5alpha-THP-facilitated lordosis that may be

[Anti-aging action of the total lactones of ginkgo on aging mice].

PubMed

Dong, Liu-yi; Fan, Li; Li, Gui-fang; Guo, Yan; Pan, Jian; Chen, Zhi-wu

2004-03-01

To investigate the effects of total lactones of ginkgo on aging by using D-galactose induced aging mice and natural aging mice. By using D-galactose induced aging mice, to detect the LF content in heart and liver, the Hyp content in liver, the MAO, GSH-Px activities and the NO content in cerebrum. The apoptosis of cerebral cell was determined by terminal deoxy-nucleotidyl transforase-mediated dUTP-digoxigenin nick end-labeling (Tunel) in natural aging mice. TLG was shown to increase the GSH-Px activities, reduce the NO content and decrease the MAO activity in cerebrum. Meanwhile, TLG was found to reduce the LF content in liver and heart and raise the Hyp content in liver. TLG was shown to inhibit apoptosis of cerebral cell and decrease the number of apoptotic cells in the brain. TLG possesses effect on antiaging via attenuating lipid peroxidation and NO and apoptosis of cerebral cells.

Peptide YY induces characteristic meal patterns of aged mice.

PubMed

Mogami, Sachiko; Yamada, Chihiro; Fujitsuka, Naoki; Hattori, Tomohisa

2017-11-01

Changes in eating behavior occur in the elderly due to oral and swallowing dysfunctions. We aimed to clarify the difference between basal meal patterns of young and aged mice in relation to appetite regulating hormones. Thirty two of young (7-week-old) and aged (23-25-month-old) C57BL/6 male mice were acclimated to a single housing and then transferred to a highly sensitive automated feeding monitoring device. Feeding behavior was monitored from the onset of the dark phase after habituation to the device. Plasma peptide YY (PYY) levels were assessed under the several feeding status or after treatment of PYY. PYY and its receptor (NPY Y2 receptor, Y2R) antagonist were intraperitoneally administered 30min before the monitoring. Although the basal 24-h meal amounts did not differ by age, the total meal time and frequency of minimum feeding activity (bout) were significantly increased and the average bout size and time per bout were significantly decreased in aged mice. PYY dynamics were abnormal and the temporal reduction in food intake by exogenous PYY was more prominent in aged mice than in young mice. PYY administration to young mice induced aged-like meal patterns, and Y2R antagonist administration to aged mice induced young-like meal patterns. Aged mice exhibited characteristic meal patterns probably due to PYY metabolism dysfunction and/or enhanced PYY-Y2R signaling, suggesting a novel method for assessing eating difficulties in aged animals and a potential target for the remedy. Copyright © 2017 Elsevier Inc. All rights reserved.

High Sensitivity of Aged Mice to Deoxynivalenol (Vomitoxin)-Induced Anorexia Corresponds to Elevated Proinflammatory Cytokine and Satiety Hormone Responses

PubMed Central

Clark, Erica S.; Flannery, Brenna M.; Gardner, Elizabeth M.; Pestka, James J.

2015-01-01

Deoxynivalenol (DON), a trichothecene mycotoxin that commonly contaminates cereal grains, is a public health concern because of its adverse effects on the gastrointestinal and immune systems. The objective of this study was to compare effects of DON on anorectic responses in aged (22 mos) and adult (3 mos) mice. Aged mice showed increased feed refusal with both acute i.p. (1 mg/kg and 5 mg/kg) and dietary (1, 2.5, 10 ppm) DON exposure in comparison to adult mice. In addition to greater suppression of food intake from dietary DON exposure, aged mice also exhibited greater but transient body weight suppression. When aged mice were acutely exposed to 1 mg/kg bw DON i.p., aged mice displayed elevated DON and DON3GlcA tissue levels and delayed clearance in comparison with adult mice. Acute DON exposure also elicited higher proinflammatory cytokine and satiety hormone responses in the plasma of the aged group compared with the adult group. Increased susceptibility to DON-induced anorexia in aged mice relative to adult mice suggests that advanced life stage could be a critical component in accurate human risk assessments for DON and other trichothecenes. PMID:26492270

High Sensitivity of Aged Mice to Deoxynivalenol (Vomitoxin)-Induced Anorexia Corresponds to Elevated Proinflammatory Cytokine and Satiety Hormone Responses.

PubMed

Clark, Erica S; Flannery, Brenna M; Gardner, Elizabeth M; Pestka, James J

2015-10-19

Deoxynivalenol (DON), a trichothecene mycotoxin that commonly contaminates cereal grains, is a public health concern because of its adverse effects on the gastrointestinal and immune systems. The objective of this study was to compare effects of DON on anorectic responses in aged (22 mos) and adult (3 mos) mice. Aged mice showed increased feed refusal with both acute i.p. (1 mg/kg and 5 mg/kg) and dietary (1, 2.5, 10 ppm) DON exposure in comparison to adult mice. In addition to greater suppression of food intake from dietary DON exposure, aged mice also exhibited greater but transient body weight suppression. When aged mice were acutely exposed to 1 mg/kg bw DON i.p., aged mice displayed elevated DON and DON3GlcA tissue levels and delayed clearance in comparison with adult mice. Acute DON exposure also elicited higher proinflammatory cytokine and satiety hormone responses in the plasma of the aged group compared with the adult group. Increased susceptibility to DON-induced anorexia in aged mice relative to adult mice suggests that advanced life stage could be a critical component in accurate human risk assessments for DON and other trichothecenes.

Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice.

PubMed

Selvaratnam, Johanna S; Robaire, Bernard

2016-09-01

Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat(-/-)) and SOD1-null (Sod(-/-)) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod(-/-) mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod(-/-) mice, while aged Cat(-/-) mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat(-/-) mice but was consistently low in young and aged Sod(-/-) mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod(-/-) and Cat(-/-) mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat(-/-) and in Sod(-/-) mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod(-/-) mice and with age in all mice. These studies show that aged Sod(-/-) mice display severe redox dysfunction, while wild-type and Cat(-/-) mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging. © 2016 by the Society for the Study of Reproduction, Inc.

Idh2 deficiency accelerates renal dysfunction in aged mice.

PubMed

Lee, Su Jeong; Cha, Hanvit; Lee, Seoyoon; Kim, Hyunjin; Ku, Hyeong Jun; Kim, Sung Hwan; Park, Jung Hyun; Lee, Jin Hyup; Park, Kwon Moo; Park, Jeen-Woo

2017-11-04

The free radical or oxidative stress theory of aging postulates that senescence is due to an accumulation of cellular oxidative damage, caused largely by reactive oxygen species (ROS) that are produced as by-products of normal metabolic processes in mitochondria. The oxidative stress may arise as a result of either increased ROS production or decreased ability to detoxify ROS. The availability of the mitochondrial NADPH pool is critical for the maintenance of the mitochondrial antioxidant system. The major enzyme responsible for generating mitochondrial NADPH is mitochondrial NADP + -dependent isocitrate dehydrogenase (IDH2). Depletion of IDH2 in mice (idh2 -/- ) shortens life span and accelerates the degeneration of multiple age-sensitive traits, such as hair grayness, skin pathology, and eye pathology. Among the various internal organs tested in this study, IDH2 depletion-induced acceleration of senescence was uniquely observed in the kidney. Renal function and structure were greatly deteriorated in 24-month-old idh2 -/- mice compared with wild-type. In addition, disruption of redox status, which promotes oxidative damage and apoptosis, was more pronounced in idh2 -/- mice. These data support a significant role for increased oxidative stress as a result of compromised mitochondrial antioxidant defenses in modulating life span in mice, and thus support the oxidative stress theory of aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of ageing on pulmonary inflammation, airway hyperresponsiveness and T and B cell responses in antigen-sensitized and -challenged mice.

PubMed

Busse, Paula J; Zhang, Teng Fei; Srivastava, Kamal; Schofield, Brian; Li, Xiu-Min

2007-09-01

The effect of ageing on several pathologic features of allergic asthma (pulmonary inflammation, eosinophilia, mucus hypersecretion), and their relationship with airway hyperresponsiveness (AHR) is not well characterized. To evaluate lung inflammation, mucus metaplasia and AHR in relationship with age in murine models of allergic asthma comparing young and older mice. Young (6 weeks) and older (6, 12, 18 months) BALB/c mice were sensitized and challenged with ovalbumin (OVA). AHR and bronchoalveolar fluid (BALF), total inflammatory cell count and differential were measured. To evaluate mucus metaplasia, quantitative PCR for the major airway mucin-associated gene, MUC-5AC, from lung tissue was measured, and lung tissue sections stained with periodic acid-Schiff (PAS) for goblet-cell enumeration. Lung tissue cytokine gene expression was determined by quantitative PCR, and systemic cytokine protein levels by ELISA from spleen-cell cultures. Antigen-specific serum IgE was determined by ELISA. AHR developed in both aged and young OVA-sensitized/challenged mice (OVA mice), and was more significantly increased in young OVA mice than in aged OVA mice. However, BALF eosinophil numbers were significantly higher, and lung histology showed greater inflammation in aged OVA mice than in young OVA mice. MUC-5AC expression and numbers of PAS+ staining bronchial epithelial cells were significantly increased in the aged OVA mice. All aged OVA mice had increased IL-5 and IFN-gamma mRNA expression in the lung and IL-5 and IFN-gamma protein levels from spleen cell cultures compared with young OVA mice. OVA-IgE was elevated to a greater extent in aged OVA mice. Although pulmonary inflammation and mucus metaplasia after antigen sensitization/challenge occurred to a greater degree in older mice, the increase in AHR was significantly less compared with younger OVA mice. Antigen treatment produced a unique cytokine profile in older mice (elevated IFN-gamma and IL-5) compared with young mice

Aging enhances liver fibrotic response in mice through hampering extracellular matrix remodeling.

PubMed

Delire, Bénédicte; Lebrun, Valérie; Selvais, Charlotte; Henriet, Patrick; Bertrand, Amélie; Horsmans, Yves; Leclercq, Isabelle A

2016-12-09

Clinical data identify age as a factor for severe liver fibrosis. We evaluate whether and how aging modulates the fibrotic response in a mouse model. Liver fibrosis was induced by CCl 4 injections (thrice weekly for 2 weeks) in 7 weeks- and 15 months-old mice (young and old, respectively). Livers were analyzed for fibrosis, inflammation and remodeling 48 and 96 hours after the last injection. Old mice developed more severe fibrosis compared to young ones as evaluated by sirius red morphometry. Expression of pro-fibrogenic genes was equally induced in the two age-groups but enhanced fibrolysis in young mice was demonstrated by a significantly higher Mmp13 induction and collagenase activity. While fibrosis resolution occurred in young mice within 96 hours, no significant fibrosis attenuation was observed in old mice. Although recruitment of monocytes-derived macrophages was similar in young and old livers, young macrophages had globally a remodeling phenotype while old ones, a pro-fibrogenic phenotype. Moreover, we observed a higher proportion of thick fibers and enhanced expression of enzymes involved in collagen maturation in old mice. Impaired fibrolysis of a matrix less prone to remodeling associated with a pro-inflammatory phenotype of infiltrated macrophages contribute to a more severe fibrosis in old mice.

Premature aging of the hippocampal neurogenic niche in adult Bmal1-deficient mice.

PubMed

Ali, Amira A H; Schwarz-Herzke, Beryl; Stahr, Anna; Prozorovski, Timour; Aktas, Orhan; von Gall, Charlotte

2015-06-01

Hippocampal neurogenesis undergoes dramatic age-related changes. Mice with targeted deletion of the clock geneBmal1 (Bmal1(-/-)) show disrupted regulation of reactive oxygen species homeostasis, accelerated aging, neurodegeneration and cognitive deficits. As proliferation of neuronal progenitor/precursor cells (NPCs) is enhanced in young Bmal1(-/-) mice, we tested the hypothesis that this results in premature aging of hippocampal neurogenic niche in adult Bmal1(-/-) mice as compared to wildtype littermates. We found significantly reduced pool of hippocampal NPCs, scattered distribution, enhanced survival of NPCs and an increased differentiation of NPCs into the astroglial lineage at the expense of the neuronal lineage. Immunoreaction of the redox sensitive histone deacetylase Sirtuine 1, peroxisomal membrane protein at 70 kDa and expression of the cell cycle inhibitor p21(Waf1/CIP1) were increased in adult Bmal1(-/-) mice. In conclusion, genetic disruption of the molecular clockwork leads to accelerated age-dependent decline in adult neurogenesis presumably as a consequence of oxidative stress.

HSP27 Alleviates Cardiac Aging in Mice via a Mechanism Involving Antioxidation and Mitophagy Activation.

PubMed

Lin, Shenglan; Wang, Yana; Zhang, Xiaojin; Kong, Qiuyue; Li, Chuanfu; Li, Yuehua; Ding, Zhengnian; Liu, Li

2016-01-01

Aging-induced cardiac dysfunction is a prominent feature of cardiac aging. Heat shock protein 27 (HSP27) protects cardiac function against ischemia or chemical challenge. We hypothesized that HSP27 attenuates cardiac aging. Transgenic (Tg) mice with cardiac-specific expression of the HSP27 gene and wild-type (WT) littermates were employed in the experiments. Echocardiography revealed a significant decline in the cardiac function of old WT mice compared with young WT mice. In striking contrast, the aging-induced impairment of cardiac function was attenuated in old Tg mice compared with old WT mice. Levels of cardiac aging markers were lower in old Tg mouse hearts than in old WT mouse hearts. Less interstitial fibrosis and lower contents of reactive oxygen species and ubiquitin-conjugated proteins were detected in old Tg hearts than in old WT hearts. Furthermore, old Tg hearts demonstrated lower accumulation of LC3-II and p62 than old WT hearts. Levels of Atg13, Vps34, and Rab7 were also higher in old Tg hearts than in old WT hearts. Additionally, old Tg hearts had higher levels of PINK1 and Parkin than old WT hearts, suggesting that mitophagy was activated in old Tg hearts. Taken together, HSP27 alleviated cardiac aging and this action involved antioxidation and mitophagy activation.

Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice1

PubMed Central

Selvaratnam, Johanna S.; Robaire, Bernard

2016-01-01

Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat−/−) and SOD1-null (Sod−/−) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod−/− mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod−/− mice, while aged Cat−/− mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat−/− mice but was consistently low in young and aged Sod−/− mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod−/− and Cat−/− mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat−/− and in Sod−/− mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod−/− mice and with age in all mice. These studies show that aged Sod−/− mice display severe redox dysfunction, while wild-type and Cat−/− mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging. PMID:27465136

Reduced COX-2 expression in aged mice is associated with impaired fracture healing.

PubMed

Naik, Amish A; Xie, Chao; Zuscik, Michael J; Kingsley, Paul; Schwarz, Edward M; Awad, Hani; Guldberg, Robert; Drissi, Hicham; Puzas, J Edward; Boyce, Brendan; Zhang, Xinping; O'Keefe, Regis J

2009-02-01

The cellular and molecular events responsible for reduced fracture healing with aging are unknown. Cyclooxygenase 2 (COX-2), the inducible regulator of prostaglandin E(2) (PGE(2)) synthesis, is critical for normal bone repair. A femoral fracture repair model was used in mice at either 7-9 or 52-56 wk of age, and healing was evaluated by imaging, histology, and gene expression studies. Aging was associated with a decreased rate of chondrogenesis, decreased bone formation, reduced callus vascularization, delayed remodeling, and altered expression of genes involved in repair and remodeling. COX-2 expression in young mice peaked at 5 days, coinciding with the transition of mesenchymal progenitors to cartilage and the onset of expression of early cartilage markers. In situ hybridization and immunohistochemistry showed that COX-2 is expressed primarily in early cartilage precursors that co-express col-2. COX-2 expression was reduced by 75% and 65% in fractures from aged mice compared with young mice on days 5 and 7, respectively. Local administration of an EP4 agonist to the fracture repair site in aged mice enhanced the rate of chondrogenesis and bone formation to levels observed in young mice, suggesting that the expression of COX-2 during the early inflammatory phase of repair regulates critical subsequent events including chondrogenesis, bone formation, and remodeling. The findings suggest that COX-2/EP4 agonists may compensate for deficient molecular signals that result in the reduced fracture healing associated with aging.

Age-related differential sensitivity to MK-801-induced locomotion and stereotypy in C57BL/6 mice

PubMed Central

Qi, Chunting; Zou, Hong; Zhang, Ruizhong; Zhao, Guoping; Jin, Meilei; Yu, Lei

2009-01-01

Psychomotor effects elicited by systemic administration of the noncompetitive NMDA (N-methyl-D-aspartate) receptor antagonist MK-801 (dizocilpine maleate) represent perturbation of glutamatergic pathways, providing an animal model for psychotic symptoms of schizophrenia. Hyperlocomotion and stereotypy are the two main psychomotor behaviors induced by MK-801. This study compared MK-801-induced hyperlocomotion and stereotypy in young (1-month old) and aged mice (12-month old), in order to determine how the aging process may influence these behaviors. The tested MK-801 doses ranged from 0.015 to 1 mg/kg. The data indicated that MK-801 impacted the aged mice more pronouncedly than the young mice, as both hyperlocomotion and stereotypy were increased significantly more in the aged mice relative to the young mice. These results suggest an age-related increase in MK-801 sensitivity in mice. PMID:18053981

Effect of aged garlic extract on immune responses to experimental fibrosarcoma tumor in BALB/c mice.

PubMed

Tabari, M Abouhosseini; Ebrahimpour, S

2014-01-01

Aged garlic extract (AGE) has many biological activities including radical scavenging, antioxidative and immunomodulative effects. In this research work, the antitumor and immunomodulatory effects of AGE against fibrosarcoma implanted tumor were studied. WEHI-164 fibrosarcoma cells were implanted subcutaneously on day 0 into the right flank of 40 BALB/c mice at age of 8 weeks. Mice were randomly categorized in two separate groups: First received AGE (100 mg/kg, IP), second group as the control group received phosphate buffered saline. Treatments were carried out 3 times/week. Tumor growth was measured and morbidity was recorded. Subpopulations of CD4+/CD8+ T cells were determined using flow cytometry. WEHI-164 cell specific cytotoxicity of splenocytes and in vitro production of interferon gamma (IFN-γ) and interleukin-4 cytokines were measured. The mice received AGE had significantly longer survival time compared with the control mice. The inhibitory effect on tumor growth was seen in AGE treated mice. The CD4+/CD8+ ratio and in vitro IFN-γ production of splenocytes were significantly increased in AGE group. WEHI-164 specific cytotoxicity of splenocytes from AGE mice was also significantly increased at 25:1 E: T ratio. Administration of AGE resulted in improved immune responses against experimentally implanted fibrosarcoma tumors in BALB/c mice. AGE showed significant effects on inhibition of tumor growth and longevity of survival times.

Sphingosine rescues aged mice from pulmonary pseudomonas infection.

PubMed

Rice, Teresa C; Pugh, Amanda M; Seitz, Aaron P; Gulbins, Erich; Nomellini, Vanessa; Caldwell, Charles C

2017-11-01

Bacterial lung infection is a leading cause of death for those 65 y or older, often requiring intensive care unit admission and mechanical ventilation, which consumes considerable health care resources. Although administration of antibiotics is the standard of care for bacterial pneumonia, its overuse has led to the emergence of multidrug resistant organisms. Therefore, alternative strategies to help minimize the effects of bacterial pneumonia in the elderly are necessary. As studies have shown that sphingosine (SPH) has inherent bacterial killing properties, our goal was to assess whether it could act as a prophylactic treatment to protect aged mice from pulmonary infection by Pseudomonas aeruginosa. Aged (51 wk) and young (8 wk) C57Bl/6 mice were used in this study. Pulmonary SPH levels were determined by histology. SPH content of microparticles was quantified using a SPH kinase assay. Pneumonia was induced by intranasally treating mice with 10 6  Colony Forming Unit (CFU) P aeruginosa. Microparticles were isolated from young mice, whereas some were further incubated with SPH. We observed that SPH levels are reduced in the bronchial epithelial cells as well as the bronchoalveolar lavage microparticles isolated from aged mice, which correlates with a susceptibility to infection. We demonstrate that SPH or microparticle treatment can protect aged mice from pulmonary P aeruginosa infection. Finally, we observed that enriching microparticles with SPH before treatment eliminated the bacterial load in P aeruginosa-infected aged mice. These data suggest that prophylactic treatment with SPH could reduce lung bacterial infections for the at-risk elderly population. Copyright © 2017 Elsevier Inc. All rights reserved.

Voluntary Wheel Running Does not Affect Lipopolysaccharide-Induced Depressive-Like Behavior in Young Adult and Aged Mice

PubMed Central

Martin, Stephen A.; Dantzer, Robert; Kelley, Keith W.; Woods, Jeffrey A.

2014-01-01

Peripheral stimulation of the innate immune system with lipopolysaccharide (LPS) causes prolonged depressive-like behavior in aged mice that is dependent on indoleamine 2,3 dioxygenase (IDO) activation. Regular moderate intensity exercise training has been shown to exert neuroprotective effects that might reduce depressive-like behavior in aged mice. The purpose of this study was to test the hypothesis that voluntary wheel running would attenuate LPS-induced depressive-like behavior and brain IDO gene expression in 4-month-old and 22-month-old C57BL/6J mice. Mice were housed with a running wheel (Voluntary Wheel Running, VWR) or no wheel (Standard) for 30 days (young adult mice) or 70 days (aged mice), after which they were intraperitoneally injected with LPS (young adult mice: 0.83 mg/kg; aged mice: 0.33 mg/kg). Young adult VWR mice ran on average 6.9 km/day, while aged VWR mice ran on average 3.4 km/day. Both young adult and aged VWR mice increased their forced exercise tolerance compared to their respective Standard control groups. VWR had no effect on LPS-induced anorexia, weight-loss, increased immobility in the tail suspension test, and decreased sucrose preference in either young adult or aged mice. Four (young adult mice) and twenty-four (aged mice) hours after injection of LPS transcripts for TNF-α, IL-1β, IL-6, and IDO were upregulated in the whole brain independently of VWR. These results indicate that prolonged physical exercise has no effect on the neuroinflammatory response to LPS and its behavioral consequences. PMID:24281669

Higher mortality and impaired elimination of bacteria in aged mice after intracerebral infection with E. coli are associated with an age-related decline of microglia and macrophage functions.

PubMed

Schütze, Sandra; Ribes, Sandra; Kaufmann, Annika; Manig, Anja; Scheffel, Jörg; Redlich, Sandra; Bunkowski, Stephanie; Hanisch, Uwe-Karsten; Brück, Wolfgang; Nau, Roland

2014-12-30

Incidence and mortality of bacterial meningitis are strongly increased in aged compared to younger adults demanding new strategies to improve prevention and therapy of bacterial central nervous system (CNS) infections the elderly. Here, we established a geriatric mouse model for an intracerebral E. coli infection which reflects the clinical situation in aged patients: After intracerebral challenge with E. coli K1, aged mice showed a higher mortality, a faster development of clinical symptoms, and a more pronounced weight loss. Elimination of bacteria and systemic inflammatory response were impaired in aged mice, however, the number of infiltrating leukocytes and microglial cells in the CNS of aged and young mice did not differ substantially. In vitro, primary microglial cells and peritoneal macrophages from aged mice phagocytosed less E. coli and released less NO and cyto-/chemokines compared to cells from young mice both without activation and after stimulation by agonists of TLR 2, 4, and 9. Our results suggest that the age-related decline of microglia and macrophage functions plays an essential role for the higher susceptibility of aged mice to intracerebral infections. Strategies to improve the phagocytic potential of aged microglial cells and macrophages appear promising for prevention and treatment of CNS infections in elderly patients.

Effect of aging and Alzheimer's disease-like pathology on brain monoamines in mice.

PubMed

Von Linstow, C U; Severino, M; Metaxas, A; Waider, J; Babcock, A A; Lesch, K P; Gramsbergen, J B; Finsen, B

2017-09-01

Aging is the greatest single risk factor of the neurodegenerative disorder Alzheimer's disease (AD). The monoaminergic system, including serotonin (5-HT), dopamine (DA) and noradrenaline (NA) modulates cognition, which is affected in AD. Changes in monoamine levels have been observed in AD, but these can both be age- and/or disease-related. We examined whether brain monoamine levels change as part of physiological aging and/or AD-like disease in APP SWE /PS1 ΔE9 (APP/PS1) transgenic mice. The neocortex, hippocampus, striatum, brainstem and cerebellum of 6-, 12-, 18- and 24-month-old B6C3 wild-type (WT) mice and of 18-month old APP/PS1 and WT mice were analysed for 5-HT, DA and NA contents by high pressure liquid chromatography (HPLC), along with neocortex from 14-month-old APP/PS1 and WT mice. While, we observed no aging effect in WT mice, we detected region-specific changes in the levels of all monoamines in 18-month-old transgenic compared with WT mice. This included reductions in 5-HT (-30%), DA (-47%) and NA (-32%) levels in the neocortex and increases of 5-HT in the brainstem (+18%). No changes were observed in any of the monoamines in the neocortex from 14-month-old APP/PS1 mice. In combination, these findings indicate that aging alone is not sufficient to affect brain monoamine levels, unlike the APP SWE /PS1 ΔE9 genotype. Copyright © 2017 Elsevier Ltd. All rights reserved.

Oral exposure to Listeria monocytogenes in aged IL-17RKO mice: A possible murine model to study listeriosis in susceptible populations.

PubMed

Alam, Mohammad S; Costales, Matthew; Cavanaugh, Christopher; Pereira, Marion; Gaines, Dennis; Williams, Kristina

2016-10-01

Foodborne Listeria monocytogenes (LM) is a cause of serious illness and death in the US. The case-fatality rate of invasive LM infection in the elderly population is >50%. The goal of this study is to establish a murine model of oral LM infection that can be used as a surrogate for human foodborne listeriosis in the geriatric population. Adult C57BL/6 (wild-type, WT) and adult or old IL17R-KO (knock-out) mice were gavaged with a murinized LM strain (Lmo-InlA m ) and monitored for body-weight loss and survivability. Tissues were collected and assayed for bacterial burden, histology, and cytokine responses. When compared to WT mice, adult IL17R-KO mice are more susceptible to LM infection and showed increased LM burden and tissue pathology and a higher mortality rate. Older LM-infected KO-mice lost significantly (p < 0.02, ANOVA) more body-weight and had a higher bacterial burden in the liver (p = 0.03) and spleen as compared to adult mice. Uninfected, aged KO-mice showed a higher baseline pro-inflammatory response when compared to uninfected adult-KO mice. After infection, the pro-inflammatory cytokine, IFN-γ, mRNA in the liver was higher in the adult mice as compared to the old mice. The anti-inflammatory cytokine, IL-10, mRNA and regulatory T-cells (CD4 + CD25 +h or CD4 + Foxp3 + ) cells in the aged mice increased significantly after infection as compared to adult mice. Expression of the T-cell activation marker, CD25 (IL-2Rα) in the aged mice did not increase significantly over baseline. These data suggest that aged IL17R-KO mice can be used as an in vivo model to study oral listeriosis and that aged mice are more susceptible to LM infection due to dysregulation of pro- and anti-inflammatory responses compared to adult mice, resulting in a protracted clearance of the infection. Published by Elsevier Ltd.

Advanced age-related denervation and fiber-type grouping in skeletal muscle of SOD1 knockout mice.

PubMed

Kostrominova, Tatiana Y

2010-11-30

In this study skeletal muscles from 1.5- and 10-month-old Cu/Zn superoxide dismutase (SOD1) homozygous knockout (JLSod1(-/-)) mice obtained from The Jackson Laboratory (C57Bl6/129SvEv background) were compared with muscles from age- and sex-matched heterozygous (JLSod1(+/-)) littermates. The results of this study were compared with previously published data on two different strains of Sod1(-/-) mice: one from Dr. Epstein's laboratory (ELSod1(-/-); C57Bl6 background) and the other from Cephalon, Inc. (CSod1(-/-); 129/CD-1 background). Grouping of succinate dehydrogenase-positive fibers characterized muscles of Sod1(-/-) mice from all three strains. The 10-month-old Sod1(-/-)C and JL mice displayed pronounced denervation of the gastrocnemius muscle, whereas the ELSod1(-/-) mice displayed a small degree of denervation at this age, but developed accelerated age-related denervation later on. Denervation markers were up-regulated in skeletal muscle of 10-month-old JLSod1(-/-) mice. This study is the first to show that metallothionein mRNA and protein expression was up-regulated in the skeletal muscle of 10-month-old JLSod1(-/-) mice and was mostly localized to the small atrophic muscle fibers. In conclusion, all three strains of Sod1(-/-) mice develop accelerated age-related muscle denervation, but the genetic background has significant influence on the progress of denervation. Copyright © 2010 Elsevier Inc. All rights reserved.

Haploinsufficiency of the Myc regulator Mtbp extends survival and delays tumor development in aging mice.

PubMed

Grieb, Brian C; Boyd, Kelli; Mitra, Ramkrishna; Eischen, Christine M

2016-10-30

Alterations of specific genes can modulate aging. Myc, a transcription factor that regulates the expression of many genes involved in critical cellular functions was shown to have a role in controlling longevity. Decreased expression of Myc inhibited many of the deleterious effects of aging and increased lifespan in mice. Without altering Myc expression, reduced levels of Mtbp, a recently identified regulator of Myc, limit Myc transcriptional activity and proliferation, while increased levels promote Myc-mediated effects. To determine the contribution of Mtbp to the effects of Myc on aging, we studied a large cohort of Mtbp heterozygous mice and littermate matched wild-type controls. Mtbp haploinsufficiency significantly increased longevity and maximal survival in mice. Reduced levels of Mtbp did not alter locomotor activity, litter size, or body size, but Mtbp heterozygous mice did exhibit elevated markers of metabolism, particularly in the liver. Mtbp +/- mice also had a significant delay in spontaneous cancer development, which was most prominent in the hematopoietic system, and an altered tumor spectrum compared to Mtbp +/+ mice. Therefore, the data suggest Mtbp is a regulator of longevity in mice that mimics some, but not all, of the properties of Myc in aging.

Age-related changes in behavior in C57BL/6J mice from young adulthood to middle age.

PubMed

Shoji, Hirotaka; Takao, Keizo; Hattori, Satoko; Miyakawa, Tsuyoshi

2016-01-28

Aging is considered to be associated with progressive changes in the brain and its associated sensory, motor, and cognitive functions. A large number of studies comparing young and aged animals have reported differences in various behaviors between age-cohorts, indicating behavioral dysfunctions related to aging. However, relatively little is known about behavioral changes from young adulthood to middle age, and the effect of age on behavior during the early stages of life remains to be understood. In order to investigate age-related changes in the behaviors of mice from young adulthood to middle age, we performed a large-scale analysis of the behavioral data obtained from our behavioral test battery involving 1739 C57BL/6J wild-type mice at 2-12 months of age. Significant behavioral differences between age groups (2-3-, 4-5-, 6-7-, and 8-12-month-old groups) were found in all the behavioral tests, including the light/dark transition, open field, elevated plus maze, rotarod, social interaction, prepulse inhibition, Porsolt forced swim, tail suspension, Barnes maze, and fear conditioning tests, except for the hot plate test. Compared with the 2-3-month-old group, the 4-5- and 6-7-month-old groups exhibited decreased locomotor activity to novel environments, motor function, acoustic startle response, social behavior, and depression-related behavior, increased prepulse inhibition, and deficits in spatial and cued fear memory. For most behaviors, the 8-12-month-old group showed similar but more pronounced changes in most of these behaviors compared with the younger age groups. Older groups exhibited increased anxiety-like behavior in the light/dark transition test whereas those groups showed seemingly decreased anxiety-like behavior measured by the elevated plus maze test. The large-scale analysis of behavioral data from our battery of behavioral tests indicated age-related changes in a wide range of behaviors from young adulthood to middle age in C57BL/6J mice, though

Subacute ibuprofen treatment rescues the synaptic and cognitive deficits in advanced-aged mice

PubMed Central

Rogers, Justin T.; Liu, Chia-Chen; Zhao, Na; Wang, Jian; Putzke, Travis; Yang, Longyu; Shinohara, Mitsuru; Fryer, John D.; Kanekiyo, Takahisa; Bu, Guojun

2017-01-01

Aging is accompanied by increased neuroinflammation, synaptic dysfunction and cognitive deficits both in rodents and humans, yet the onset and progression of these deficits throughout the life span remain unknown. These aging-related deficits affect the quality of life and present challenges to our aging society. Here, we defined age-dependent and progressive impairments of synaptic and cognitive functions and showed that reducing astrocyte-related neuroinflammation through anti-inflammatory drug treatment in aged mice reverses these events. By comparing young (3 months), middle-aged (18 months), aged (24 months) and advanced-aged wild-type mice (30 months), we found that the levels of an astrocytic marker, GFAP, progressively increased after 18 months of age, which preceded the decreases of the synaptic marker PSD-95. Hippocampal long-term potentiation (LTP) was also suppressed in an age-dependent manner, where significant deficits were observed after 24 months of age. Fear conditioning tests demonstrated that associative memory in the context and cued conditions was decreased starting at the ages of 18 and 30 months, respectively. When the mice were tested on hidden platform water maze, spatial learning memory was significantly impaired after 24 months of age. Importantly, subacute treatment with the anti-inflammatory drug ibuprofen suppressed astrocyte activation, and restored synaptic plasticity and memory function in advanced-aged mice. These results support the critical contribution of aging-related inflammatory responses to hippocampal-dependent cognitive function and synaptic plasticity, in particular during advanced aging. Our findings provide strong evidence that suppression of neuroinflammation could be a promising treatment strategy to preserve cognition during aging. PMID:28254590

Age-dependent inhibition of pentobarbital sleeping time by ozone in mice and rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canada, A.T.; Calabrese, E.J.; Leonard, D.

1986-09-01

The effect of age on the metabolism of pentobarbital in mice and rats was investigated following exposure to 0.3 ppm of ozone for 3.75 hr. Young animals were 2.5 months of age and the mature were 18 months. The pentobarbital sleeping time was significantly prolonged following the ozone exposure in both the mice and rats when compared with an air control. No ozone effect on sleeping time was found in the young animals. The results indicate that there may be an age-related sensitivity to the occurrence of ozone-related inhibition of pentobarbital metabolism.

Innate Immune Dysfunctions in Aged Mice Facilitate the Systemic Dissemination of Methicillin-Resistant S. aureus

PubMed Central

Tseng, Ching Wen; Kyme, Pierre A.; Arruda, Andrea; Ramanujan, V. Krishnan; Tawackoli, Wafa; Liu, George Y.

2012-01-01

Elderly humans show increased susceptibility to invasive staphylococcal disease after skin and soft tissue infection. However, it is not understood how host immunity changes with aging, and how that predisposes to invasive disease. In a model of severe skin infection, we showed that aged mice (16- to 20-month-old) exhibit dramatic bacterial dissemination compared with young adult mice (2-month-old). Bacterial dissemination was associated with significant reductions of CXCL1 (KC), polymorphonuclear cells (PMNs), and extracellular DNA traps (NETs) at the infection site. PMNs and primary skin fibroblasts isolated from aged mice showed decreased secretion of CXCL2 (MIP-2) and KC in response to MRSA, and in vitro analyses of mitochondrial functions revealed that the mitochondrial electron transport chain complex I plays a significant role in induction of chemokines in the cells isolated from young but not old mice. Additionally, PMNs isolated from aged mice have reduced ability to form NETs and to kill MRSA. Expression of nuclease by S. aureus led to increased bacterial systemic dissemination in young but not old mice, suggesting that defective NETs formation in elderly mice permitted nuclease and non-nuclease expressing S. aureus to disseminate equally well. Overall, these findings suggest that gross impairment of both skin barrier function and innate immunity contributes to the propensity for MRSA to disseminate in aged mice. Furthermore, the study indicates that contribution of bacterial factors to pathogenicity may vary with host age. PMID:22844481

Transcriptional and phenotypic changes in aorta and aortic valve with aging and MnSOD deficiency in mice

PubMed Central

Roos, Carolyn M.; Hagler, Michael; Zhang, Bin; Oehler, Elise A.; Arghami, Arman

2013-01-01

The purpose of this study was to characterize changes in antioxidant and age-related gene expression in aorta and aortic valve with aging, and test the hypothesis that increased mitochondrial oxidative stress accelerates age-related endothelial and aortic valve dysfunction. Wild-type (MnSOD+/+) and manganese SOD heterozygous haploinsufficient (MnSOD+/−) mice were studied at 3 and 18 mo of age. In aorta from wild-type mice, antioxidant expression was preserved, although there were age-associated increases in Nox2 expression. Haploinsufficiency of MnSOD did not alter antioxidant expression in aorta, but increased expression of Nox2. When compared with that of aorta, age-associated reductions in antioxidant expression were larger in aortic valves from wild-type and MnSOD haploinsufficient mice, although Nox2 expression was unchanged. Similarly, sirtuin expression was relatively well-preserved in aorta from both genotypes, whereas expression of SIRT1, SIRT2, SIRT3, SIRT4, and SIRT6 were significantly reduced in the aortic valve. Expression of p16ink4a, a marker of cellular senescence, was profoundly increased in both aorta and aortic valve from MnSOD+/+ and MnSOD+/− mice. Functionally, we observed comparable age-associated reductions in endothelial function in aorta from both MnSOD+/+ and MnSOD+/− mice. Interestingly, inhibition of NAD(P)H oxidase with apocynin or gp91ds-tat improved endothelial function in MnSOD+/+ mice but significantly impaired endothelial function in MnSOD+/− mice at both ages. Aortic valve function was not impaired by aging or MnSOD haploinsufficiency. Changes in antioxidant and sirtuin gene expression with aging differ dramatically between aorta and aortic valve. Furthermore, although MnSOD does not result in overt cardiovascular dysfunction with aging, compensatory transcriptional responses to MnSOD deficiency appear to be tissue specific. PMID:23997094

Histone deacetylase inhibitors reverse age-related increases in side effects of haloperidol in mice.

PubMed

Montalvo-Ortiz, Janitza L; Fisher, Daniel W; Rodríguez, Guadalupe; Fang, Deyu; Csernansky, John G; Dong, Hongxin

2017-08-01

Older patients can be especially susceptible to antipsychotic-induced side effects, and the pharmacodynamic mechanism underlying this phenomenon remains unclear. We hypothesized that age-related epigenetic alterations lead to decreased expression and functionality of the dopamine D2 receptor (D2R), contributing to this susceptibility. In this study, we treated young (2-3 months old) and aged (22-24 months old) C57BL/6 mice with the D2R antagonist haloperidol (HAL) once a day for 14 days to evaluate HAL-induced motor side effects. In addition, we pretreated separate groups of young and aged mice with histone deacetylase (HDAC) inhibitors valproic acid (VPA) or entinostat (MS-275) and then administered HAL. Our results show that the motor side effects of HAL are exaggerated in aged mice as compared to young mice and that HDAC inhibitors are able to reverse the severity of these deficits. HAL-induced motor deficits in aged mice are associated with an age- and drug-dependent decrease in striatal D2R protein levels and functionality. Further, histone acetylation was reduced while histone tri-methylation was increased at specific lysine residues of H3 and H4 within the Drd2 promoter in the striatum of aged mice. HDAC inhibitors, particularly VPA, restored striatal D2R protein levels and functionality and reversed age- and drug-related histone modifications at the Drd2 promoter. These results suggest that epigenetic changes at the striatal Drd2 promoter drive age-related increases in antipsychotic side effect susceptibility, and HDAC inhibitors may be an effective adjunct treatment strategy to reduce side effects in aged populations.

Effects of voluntary wheel running on LPS-induced sickness behavior in aged mice.

PubMed

Martin, Stephen A; Pence, Brandt D; Greene, Ryan M; Johnson, Stephanie J; Dantzer, Robert; Kelley, Keith W; Woods, Jeffrey A

2013-03-01

Peripheral stimulation of the innate immune system with LPS causes exaggerated neuroinflammation and prolonged sickness behavior in aged mice. Regular moderate intensity exercise has been shown to exert anti-inflammatory effects that may protect against inappropriate neuroinflammation and sickness in aged mice. The purpose of this study was to test the hypothesis that voluntary wheel running would attenuate LPS-induced sickness behavior and proinflammatory cytokine gene expression in ~22-month-old C57BL/6J mice. Mice were housed with a running wheel (VWR), locked-wheel (Locked), or no wheel (Standard) for 10 weeks, after which they were intraperitoneally injected with LPS across a range of doses (0.02, 0.08, 0.16, 0.33 mg/kg). VWR mice ran on average 3.5 km/day and lost significantly more body weight and body fat, and increased their forced exercise tolerance compared to Locked and Shoebox mice. VWR had no effect on LPS-induced anorexia, adipsia, weight-loss, or reductions in locomotor activity at any LPS dose when compared to Locked and Shoebox groups. LPS induced sickness behavior in a dose-dependent fashion (0.33>0.02 mg/kg). Twenty-four hours post-injection (0.33 mg/kg LPS or Saline) we found a LPS-induced upregulation of whole brain TNFα, IL-1β, and IL-10 mRNA, and increased IL-1β and IL-6 in the spleen and liver; these effects were not attenuated by VWR. We conclude that VWR does not reduce LPS-induced exaggerated or prolonged sickness behavior in aged animals, or 24h post-injection (0.33 mg/kg LPS or Saline) brain and peripheral proinflammatory cytokine gene expression. The necessity of the sickness response is critical for survival and may outweigh the subtle benefits of exercise training in aged animals. Copyright © 2012 Elsevier Inc. All rights reserved.

Age-related arterial immune cell infiltration in mice is attenuated by caloric restriction or voluntary exercise.

PubMed

Trott, Daniel W; Henson, Grant D; Ho, Mi H T; Allison, Sheilah A; Lesniewski, Lisa A; Donato, Anthony J

2016-12-22

Age-related arterial inflammation is associated with dysfunction of the arteries and increased risk for cardiovascular disease. To determine if aging increases arterial immune cell infiltration as well as the populations of immune cells principally involved, we tested the hypothesis that large elastic and resistance arteries in old mice would exhibit increased immune cell infiltration compared to young controls. Additionally, we hypothesized that vasoprotective lifestyle interventions such as lifelong caloric restriction or 8weeks of voluntary wheel running would attenuate age-related arterial immune cell infiltration. The aorta and mesenteric vasculature with surrounding perivascular adipose was excised from young normal chow (YNC, 4-6months, n=10), old normal chow (ONC, 28-29months, n=11), old caloric restricted (OCR, 28-29months, n=9), and old voluntary running (OVR, 28-29months, n=5) mice and digested to a single cell suspension. The cells were then labeled with antibodies against CD45 (total leukocytes), CD3 (pan T cells), CD4 (T helper cells), CD8 (cytotoxic T cells), CD19 (B cells), CD11b, and F4/80 (macrophages) and analyzed by flow cytometry. Total leukocytes, T cells (both CD4 + and CD8 + subsets), B cells, and macrophages in both aorta and mesentery were all 5- to 6-fold greater in ONC compared to YNC. Age-related increases in T cell (both CD4 + and CD8 + ), B cell, and macrophage infiltration in aorta were abolished in OCR mice. OVR mice exhibited 50% lower aortic T cell and normalized macrophage infiltration. B cell infiltration was not affected by VR. Age-related mesenteric CD8 + T cell and macrophage infiltration was normalized in OCR and OVR mice compared to young mice, whereas B cell infiltration was normalized by CR but not VR. Splenic CD4 + T cells from ONC mice exhibited a 3-fold increase in gene expression for the T helper (Th) 1 transcription factor, Tbet, and a 4-fold increase in FoxP3, a T regulatory cell transcription factor, compared to

Consuming a Diet Supplemented with Resveratrol Reduced Infection-Related Neuroinflammation and Deficits in Working Memory in Aged Mice

PubMed Central

Abraham, Jayne

2009-01-01

Abstract Aged mice treated peripherally with lipopolysaccharide (LPS) show an exaggerated neuroinflammatory response and cognitive deficits compared to adults. Considerable evidence suggests resveratrol, a polyphenol found in red grapes, has potent antiinflammatory effects in the periphery, but its effects on the central inflammatory response and cognitive behavior are unknown. Therefore, the current study investigated if resveratrol dietary supplementation would inhibit neuroinflammation as well as behavioral and cognitive deficits in aged mice given LPS to mimic a peripheral infection. In initial studies, adult (3–6 months) and aged (22–24 months) mice were provided control or resveratrol-supplemented diet for 4 weeks and then injected intraperitoneally (i.p.) with saline or LPS, and locomotor activity and spatial working memory were assessed. As anticipated, deficits in locomotor activity and spatial working memory indicated aged mice are more sensitive to LPS compared to adults. More importantly, the LPS-induced deficits in aged animals were mitigated by dietary supplementation of resveratrol. In addition, resveratrol consumption reduced LPS-induced interleukin-1β (IL-1β) in plasma and the IL-1β mRNA in the hippocampus of aged mice. Finally, pretreatment of BV-2 microglial cells with resveratrol potently inhibited LPS-induced IL-1β production. These data show that aged mice are more sensitive than adult mice to both the inflammatory and cognitive effects of peripheral immune stimulation and suggest that resveratrol may be useful for attenuating acute cognitive disorders in elderly individuals with an infection. PMID:20041738

On-going electroencephalographic rhythms related to cortical arousal in wild-type mice: the effect of aging.

PubMed

Del Percio, Claudio; Drinkenburg, Wilhelmus; Lopez, Susanna; Infarinato, Francesco; Bastlund, Jesper Frank; Laursen, Bettina; Pedersen, Jan T; Christensen, Ditte Zerlang; Forloni, Gianluigi; Frasca, Angelisa; Noè, Francesco M; Bentivoglio, Marina; Fabene, Paolo Francesco; Bertini, Giuseppe; Colavito, Valeria; Kelley, Jonathan; Dix, Sophie; Richardson, Jill C; Babiloni, Claudio

2017-01-01

Resting state electroencephalographic (EEG) rhythms reflect the fluctuation of cortical arousal and vigilance in a typical clinical setting, namely the EEG recording for few minutes with eyes closed (i.e., passive condition) and eyes open (i.e., active condition). Can this procedure be back-translated to C57 (wild type) mice for aging studies? On-going EEG rhythms were recorded from a frontoparietal bipolar channel in 85 (19 females) C57 mice. Male mice were subdivided into 3 groups: 25 young (4.5-6 months), 18 middle-aged (12-15 months), and 23 old (20-24 months) mice to test the effect of aging. EEG power density was compared between short periods (about 5 minutes) of awake quiet behavior (passive) and dynamic exploration of the cage (active). Compared with the passive condition, the active condition induced decreased EEG power at 1-2 Hz and increased EEG power at 6-10 Hz in the group of 85 mice. Concerning the aging effects, the passive condition showed higher EEG power at 1-2 Hz in the old group than that in the others. Furthermore, the active condition exhibited a maximum EEG power at 6-8 Hz in the former group and 8-10 Hz in the latter. In the present conditions, delta and theta EEG rhythms reflected changes in cortical arousal and vigilance in freely behaving C57 mice across aging. These changes resemble the so-called slowing of resting state EEG rhythms observed in humans across physiological and pathological aging. The present EEG procedures may be used to enhance preclinical phases of drug discovery in mice for understanding the neurophysiological effects of new compounds against brain aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Age-related decline in oligodendrogenesis retards white matter repair in mice.

PubMed

Miyamoto, Nobukazu; Pham, Loc-Duyen D; Hayakawa, Kazuhide; Matsuzaki, Toshinori; Seo, Ji Hae; Magnain, Caroline; Ayata, Cenk; Kim, Kyu-Won; Boas, David; Lo, Eng H; Arai, Ken

2013-09-01

Aging is one of the major risk factors for white matter injury in cerebrovascular disease. However, the effects of age on the mechanisms of injury/repair in white matter remain to be fully elucidated. Here, we ask whether, compared with young brains, white matter regions in older brains may be more vulnerable in part because of decreased rates of compensatory oligodendrogenesis after injury. A mouse model of prolonged cerebral hypoperfusion was prepared by bilateral common carotid artery stenosis in 2-month and 8-month-old mice. Matching in vitro studies were performed by subjecting oligodendrocyte precursor cells to sublethal 7-day CoCl2 treatment to induce chemical hypoxic stress. Baseline myelin density in the corpus callosum was similar in 2-month and 8-month-old mice. But after induction of prolonged cerebral hypoperfusion, older mice showed more severe white matter injury together with worse deficits in working memory. The numbers of newborn oligodendrocytes and their precursors were increased by cerebral hypoperfusion in young mice, whereas these endogenous responses were significantly dampened in older mice. Defects in cyclic AMP response element-binding protein signaling may be involved because activating cyclic AMP response element-binding protein with the type-III phosphodiesterase inhibitor cilostazol in older mice restored the differentiation of oligodendrocyte precursor cells, alleviated myelin loss, and improved cognitive dysfunction during cerebral hypoperfusion. Cell culture systems confirmed that cilostazol promoted the differentiation of oligodendrocyte precursor cells. An age-related decline in cyclic AMP response element-binding protein-mediated oligodendrogenesis may compromise endogenous white matter repair mechanisms, and therefore, drugs that activate cyclic AMP response element-binding protein signaling provide a potential therapeutic approach for treating white matter injury in aging brains.

Impact of β-hydroxy β-methylbutyrate (HMB) on age-related functional deficits in mice.

PubMed

Munroe, Michael; Pincu, Yair; Merritt, Jennifer; Cobert, Adam; Brander, Ryan; Jensen, Tor; Rhodes, Justin; Boppart, Marni D

2017-01-01

β-Hydroxy β-methylbutyrate (HMB) is a metabolite of the essential amino acid leucine. Recent studies demonstrate a decline in plasma HMB concentrations in humans across the lifespan, and HMB supplementation may be able to preserve muscle mass and strength in older adults. However, the impact of HMB supplementation on hippocampal neurogenesis and cognition remains largely unexplored. The purpose of this study was to simultaneously evaluate the impact of HMB on muscle strength, neurogenesis and cognition in young and aged mice. In addition, we evaluated the influence of HMB on muscle-resident mesenchymal stem/stromal cell (Sca-1 + CD45 - ; mMSC) function to address these cells potential to regulate physiological outcomes. Three month-old (n=20) and 24 month-old (n=18) female C57BL/6 mice were provided with either Ca-HMB or Ca-Lactate in a sucrose solution twice per day for 5.5weeks at a dose of 450mg/kg body weight. Significant decreases in relative peak and mean force, balance, and neurogenesis were observed in aged mice compared to young (age main effects, p≤0.05). Short-term HMB supplementation did not alter activity, balance, neurogenesis, or cognitive function in young or aged mice, yet HMB preserved relative peak force in aged mice. mMSC gene expression was significantly reduced with age, but HMB supplementation was able to recover expression of select growth factors known to stimulate muscle repair (HGF, LIF). Overall, our findings demonstrate that while short-term HMB supplementation does not appear to affect neurogenesis or cognitive function in young or aged mice, HMB may maintain muscle strength in aged mice in a manner dependent on mMSC function. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of Aging on Proprioceptive Sensory Neurons and Intrafusal Muscle Fibers in Mice.

PubMed

Vaughan, Sydney K; Stanley, Olivia L; Valdez, Gregorio

2017-06-01

The impact of aging on proprioceptive sensory neurons and intrafusal muscle fibers (IMFs) remains largely unexplored despite the central function these cells play in modulating voluntary movements. Here, we show that proprioceptive sensory neurons undergo deleterious morphological changes in middle age (11- to 13-month-old) and old (15- to 21-month-old) mice. In the extensor digitorum longus and soleus muscles of middle age and old mice, there is a significant increase in the number of Ia afferents with large swellings that fail to properly wrap around IMFs compared with young adult (2- to 4-month-old) mice. Fewer II afferents were also found in the same muscles of middle age and old mice. Although these age-related changes in peripheral nerve endings were accompanied by degeneration of proprioceptive sensory neuron cell bodies in dorsal root ganglia (DRG), the morphology and number of IMFs remained unchanged. Our analysis also revealed normal levels of neurotrophin 3 (NT3) but dysregulated expression of the tyrosine kinase receptor C (TrkC) in aged muscles and DRGs, respectively. These results show that proprioceptive sensory neurons degenerate prior to atrophy of IMFs during aging, and in the presence of the NT3/TrkC signaling axis. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

HDAC Inhibitors Restore the Capacity of Aged Mice to Respond to Haloperidol through Modulation of Histone Acetylation

PubMed Central

Montalvo-Ortiz, Janitza L; Keegan, Jack; Gallardo, Christopher; Gerst, Nicolas; Tetsuka, Kazuhiro; Tucker, Chris; Matsumoto, Mitsuyuki; Fang, Deyu; Csernansky, John G; Dong, Hongxin

2014-01-01

Antipsychotic drugs are widely prescribed to elderly patients for the treatment of a variety of psychopathological conditions, including psychosis and the behavioral disturbances associated with dementia. However, clinical experience suggests that these drugs may be less efficacious in the elderly individuals than in the young. Recent studies suggest that aging may be associated with epigenetic changes and that valproic acid (VPA), a histone deacetylase inhibitor, may reverse such changes. However, it is not yet known whether HDAC inhibitors can modulate age-related epigenetic changes that may impact antipsychotic drug action. In this study, we analyzed conditioned avoidance response (CAR) and c-Fos expression patterns to elucidate the effect of HDAC inhibitors VPA and entinostat (MS-275) on behavioral and molecular markers of the effects of haloperidol (HAL) in aged mice. Our results showed that HAL administration failed to suppress the avoidance response during the CAR test, suggesting an age-related decrease in drug efficacy. In addition, HAL-induced c-Fos expression in the nucleus accumbens shell and prefrontal cortex was significantly lower in aged mice as compared with young mice. Pretreatment with VPA and MS-275 significantly improved HAL effects on the CAR test in aged mice. Also, VPA and MS-275 pretreatment restored HAL-induced increases in c-Fos expression in the nucleus accumbens shell and prefrontal cortex of aged mice to levels comparable with those observed in young mice. Lastly, but most importantly, increases in c-Fos expression and HAL efficacy in the CAR test of the HAL+VPA and HAL+MS-275 groups were correlated with elevated histone acetylation at the c-fos promoter region in aged mice. These findings suggest that pretreatment with VPA or MS-275 increases the behavioral and molecular effects of HAL in aged mice and that these effects occur via modulation of age-related histone hypoacetylation in the nucleus accumbens shell and prefrontal cortex

A comparative study of the characterization of miR-155 in knockout mice

PubMed Central

Zhang, Dong; Cui, Yongchun; Li, Bin; Luo, Xiaokang; Li, Bo; Tang, Yue

2017-01-01

miR-155 is one of the most important miRNAs and plays a very important role in numerous biological processes. However, few studies have characterized this miRNA in mice under normal physiological conditions. We aimed to characterize miR-155 in vivo by using a comparative analysis. In our study, we compared miR-155 knockout (KO) mice with C57BL/6 wild type (WT) mice in order to characterize miR-155 in mice under normal physiological conditions using many evaluation methods, including a reproductive performance analysis, growth curve, ultrasonic estimation, haematological examination, and histopathological analysis. These analyses showed no significant differences between groups in the main evaluation indices. The growth and development were nearly normal for all mice and did not differ between the control and model groups. Using a comparative analysis and a summary of related studies published in recent years, we found that miR-155 was not essential for normal physiological processes in 8-week-old mice. miR-155 deficiency did not affect the development and growth of naturally ageing mice during the 42 days after birth. Thus, studying the complex biological functions of miR-155 requires the further use of KO mouse models. PMID:28278287

Ageing and recurrent episodes of neuroinflammation promote progressive experimental autoimmune encephalomyelitis in Biozzi ABH mice.

PubMed

Peferoen, Laura A N; Breur, Marjolein; van de Berg, Sarah; Peferoen-Baert, Regina; Boddeke, Erik H W G M; van der Valk, Paul; Pryce, Gareth; van Noort, Johannes M; Baker, David; Amor, Sandra

2016-10-01

Current therapies for multiple sclerosis (MS) reduce the frequency of relapses by modulating adaptive immune responses but fail to limit the irreversible neurodegeneration driving progressive disability. Experimental autoimmune encephalomyelitis (EAE) in Biozzi ABH mice recapitulates clinical features of MS including relapsing-remitting episodes and secondary-progressive disability. To address the contribution of recurrent inflammatory events and ageing as factors that amplify progressive neurological disease, we examined EAE in 8- to 12-week-old and 12-month-old ABH mice. Compared with the relapsing-remitting (RREAE) and secondary progressive (SPEAE) EAE observed in young mice, old mice developed progressive disease from onset (PEAE) associated with pronounced axonal damage and increased numbers of CD3(+) T cells and microglia/macrophages, but not B cells. Whereas the clinical neurological features of PEAE and SPEAE were comparable, the pathology was distinct. SPEAE was associated with significantly reduced perivascular infiltrates and T-cell numbers in the central nervous system (CNS) compared with PEAE and the acute phase of RREAE. In contrast to perivascular infiltrates that declined during progression from RREAE into SPEAE, the numbers of microglia clusters remained constant. Similar to what is observed during MS, the microglia clusters emerging during EAE were associated with axonal damage and oligodendrocytes expressing heat-shock protein B5, but not lymphocytes. Taken together, our data reveal that the course of EAE is dependent on the age of the mice. Younger mice show a relapsing-remitting phase followed by progressive disease, whereas old mice immediately show progression. This indicates that recurrent episodes of inflammation in the CNS, as well as age, contribute to progressive neurological disease. © 2016 John Wiley & Sons Ltd.

Generating Chimeric Mice by Using Embryos from Nonsuperovulated BALB/c Mice Compared with Superovulated BALB/c and Albino C57BL/6 Mice.

PubMed

Esmail, Michael Y; Qi, Peimin; Connor, Aurora Burds; Fox, James G; García, Alexis

2016-01-01

The reliable generation of high-percentage chimeras from gene-targeted C57BL/6 embryonic stem cells has proven challenging, despite optimization of cell culture and microinjection techniques. To improve the efficiency of this procedure, we compared the generation of chimeras by using 3 different inbred, albino host, embryo-generating protocols: BALB/cAnNTac (BALB/c) donor mice superovulated at 4 wk of age, 12-wk-old BALB/c donor mice without superovulation, and C57BL/6NTac-Tyr(tm1Arte) (albino B6) mice superovulated at 4 wk of age. Key parameters measured included the average number of injectable embryos per donor, the percentage of live pups born from the total number of embryos transferred to recipients, and the number of chimeric pups with high embryonic-stem-cell contribution by coat color. Although albino B6 donors produced significantly more injectable embryos than did BALB/c donors, 12-wk-old BALB/c donor produced high-percentage (at least 70%) chimeras more than 2.5 times as often as did albino B6 mice and 20 times more efficiently than did 4-wk-old BALB/c donors. These findings clearly suggest that 12-wk-old BALB/c mice be used as blastocyst donors to reduce the number of mice used to generate each chimera, reduce the production of low-percentage chimeras, and maximize the generation of high-percentage chimeras from C57BL/6 embryonic stem cells.

Mangiferin induces islet regeneration in aged mice through regulating p16INK4a.

PubMed

Wang, Hailian; He, Xia; Lei, Tiantian; Liu, Yilong; Huai, Guoli; Sun, Minghan; Deng, Shaoping; Yang, Hongji; Tong, Rongsheng; Wang, Yi

2018-06-01

Previous studies by our group on mangiferin demonstrated that it exerts an anti‑hyperglycemic effect through the regulation of cell cycle proteins in 3‑month‑old, partially pancreatectomized (PPx) mice. However, β‑cell proliferation is known to become severely restricted with advanced age. Therefore, it is unknown whether mangiferin is able to reverse the diabetic condition and retain β‑cell regeneration capability in aged mice. In the present study, 12‑month‑old C57BL/6J mice that had undergone PPx were subjected to mangiferin treatment (90 mg/kg) for 28 days. Mangiferin‑treated aged mice exhibited decreased blood glucose levels and increased glucose tolerance, which was accompanied with higher serum insulin levels when compared with those in untreated PPx control mice. In addition, islet hyperplasia, elevated β‑cell proliferation and reduced β‑cell apoptosis were also identified in the mice that received mangiferin treatment. Further studies on the mRNA transcript and protein expression levels indicated comparatively increased levels of cyclins D1 and D2 and cyclin‑dependent kinase 4 in mangiferin‑treated mice, while the levels of p27Kip1 and p16INK4a were decreased relative to those in the untreated PPx controls. Of note, mangiferin treatment improved the proliferation rate of islet β‑cells in adult mice overexpressing p16INK4a, suggesting that mangiferin induced β‑cell proliferation via the regulation of p16INK4a. In addition, the mRNA transcription levels of critical genes associated with insulin secretion, including pancreatic and duodenal homeobox 1, glucose transporter 2 and glucokinase, were observed to be upregulated after mangiferin treatment. Taken together, it was indicated that mangiferin treatment significantly induced β‑cell proliferation and inhibited β‑cell apoptosis by regulating cell cycle checkpoint proteins. Furthermore, mangiferin was also demonstrated to regulate genes associated with insulin

Mangiferin induces islet regeneration in aged mice through regulating p16INK4a

PubMed Central

Liu, Yilong; Huai, Guoli; Sun, Minghan; Deng, Shaoping; Yang, Hongji; Tong, Rongsheng; Wang, Yi

2018-01-01

Previous studies by our group on mangiferin demonstrated that it exerts an antihyperglycemic effect through the regulation of cell cycle proteins in 3-month-old, partially pancreatectomized (PPx) mice. However, β-cell proliferation is known to become severely restricted with advanced age. Therefore, it is unknown whether mangiferin is able to reverse the diabetic condition and retain β-cell regeneration capability in aged mice. In the present study, 12-month-old C57BL/6J mice that had undergone PPx were subjected to mangiferin treatment (90 mg/kg) for 28 days. Mangiferin-treated aged mice exhibited decreased blood glucose levels and increased glucose tolerance, which was accompanied with higher serum insulin levels when compared with those in untreated PPx control mice. In addition, islet hyperplasia, elevated β-cell proliferation and reduced β-cell apoptosis were also identified in the mice that received mangiferin treatment. Further studies on the mRNA transcript and protein expression levels indicated comparatively increased levels of cyclins D1 and D2 and cyclin-dependent kinase 4 in mangiferin-treated mice, while the levels of p27Kip1 and p16INK4a were decreased relative to those in the untreated PPx controls. Of note, mangiferin treatment improved the proliferation rate of islet β-cells in adult mice overexpressing p16INK4a, suggesting that mangiferin induced β-cell proliferation via the regulation of p16INK4a. In addition, the mRNA transcription levels of critical genes associated with insulin secretion, including pancreatic and duodenal homeobox 1, glucose transporter 2 and glucokinase, were observed to be upregulated after mangiferin treatment. Taken together, it was indicated that mangiferin treatment significantly induced β-cell proliferation and inhibited β-cell apoptosis by regulating cell cycle checkpoint proteins. Furthermore, mangiferin was also demonstrated to regulate genes associated with insulin secretion. Collectively these, results

The increase of anterior pituitary dopamine in aging C57BL/6J female mice is caused by ovarian steroids, not intrinsic pituitary aging.

PubMed

Telford, N; Mobbs, C V; Sinha, Y N; Finch, C E

1986-01-01

We describe how the increase of anterior pituitary dopamine (DA) during aging in female mice is related to altered secretion of ovarian steroids during reproductive senescence. A number of age-correlated neuroendocrine changes in female rodents result from cumulative exposure to ovarian steroids over a lifetime of estrous cycles, or from the altered pattern of ovarian steroid secretion concomitant with reproductive senescence. Pituitary DA has been shown to increase with age in female rats. To examine how the age-correlated increase of pituitary DA may depend on estradiol (E2), we measured pituitary DA and serum prolactin (PRL) in the following groups of female mice: young (7 months) cycling, middle-aged (14 months) cycling and non-cycling, old (17 months) non-cycling, old (17 months) ovariectomized (OVX) at 4 months, and young mice given 0.2 mg E2 valerate or E2 implants. Mice from some of these groups were OVX 1, 4 or 8 weeks before sacrifice. Compared with young controls, 14-month-old cycling or non-cycling mice had 3-fold higher pituitary DA, and 17-month-old non-cycling mice had 5-fold higher pituitary DA. OVX for 2 or 13 months before sacrifice abolished the effect of age; OVX of young mice had no effect on pituitary DA. Three weeks after implantation of E2 into OVX young mice or 7 weeks after injection of E2 valerate in intact young mice, pituitary DA was elevated. The E2-sensitive fraction of pituitary DA does not appear to decrease PRL secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Cold hypersensitivity increases with age in mice with sickle cell disease.

PubMed

Zappia, Katherine J; Garrison, Sheldon R; Hillery, Cheryl A; Stucky, Cheryl L

2014-12-01

Sickle cell disease (SCD) is associated with acute vaso-occlusive crises that trigger painful episodes and frequently involves ongoing, chronic pain. In addition, both humans and mice with SCD experience heightened cold sensitivity. However, studies have not addressed the mechanism(s) underlying the cold sensitization or its progression with age. Here we measured thermotaxis behavior in young and aged mice with severe SCD. Sickle mice had a marked increase in cold sensitivity measured by a cold preference test. Furthermore, cold hypersensitivity worsened with advanced age. We assessed whether enhanced peripheral input contributes to the chronic cold pain behavior by recording from C fibers, many of which are cold sensitive, in skin-nerve preparations. We observed that C fibers from sickle mice displayed a shift to warmer (more sensitive) cold detection thresholds. To address mechanisms underlying the cold sensitization in primary afferent neurons, we quantified mRNA expression levels for ion channels thought to be involved in cold detection. These included the transient receptor potential melastatin 8 (Trpm8) and transient receptor potential ankyrin 1 (Trpa1) channels, as well as the 2-pore domain potassium channels, TREK-1 (Kcnk2), TREK-2 (Kcnk10), and TRAAK (Kcnk4). Surprisingly, transcript expression levels of all of these channels were comparable between sickle and control mice. We further examined transcript expression of 83 additional pain-related genes, and found increased mRNA levels for endothelin 1 and tachykinin receptor 1. These factors may contribute to hypersensitivity in sickle mice at both the afferent and behavioral levels. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Resilience in Aging Mice

PubMed Central

Kirkland, James L.; Stout, Michael B.

2016-01-01

Abstract Recently discovered interventions that target fundamental aging mechanisms have been shown to increase life span in mice and other species, and in some cases, these same manipulations have been shown to enhance health span and alleviate multiple age-related diseases and conditions. Aging is generally associated with decreases in resilience, the capacity to respond to or recover from clinically relevant stresses such as surgery, infections, or vascular events. We hypothesize that the age-related increase in susceptibility to those diseases and conditions is driven by or associated with the decrease in resilience. Thus, a test for resilience at middle age or even earlier could represent a surrogate approach to test the hypothesis that an intervention delays the process of aging itself. For this, animal models to test resilience accurately and predictably are needed. In addition, interventions that increase resilience might lead to treatments aimed at enhancing recovery following acute illnesses, or preventing poor outcomes from medical interventions in older, prefrail subjects. At a meeting of basic researchers and clinicians engaged in research on mechanisms of aging and care of the elderly, the merits and drawbacks of investigating effects of interventions on resilience in mice were considered. Available and potential stressors for assessing physiological resilience as well as the notion of developing a limited battery of such stressors and how to rank them were discussed. Relevant ranking parameters included value in assessing general health (as opposed to focusing on a single physiological system), ease of use, cost, reproducibility, clinical relevance, and feasibility of being repeated in the same animal longitudinally. During the discussions it became clear that, while this is an important area, very little is known or established. Much more research is needed in the near future to develop appropriate tests of resilience in animal models within an

High Intensity Interval Training Improves Physical Performance and Frailty in Aged Mice.

PubMed

Seldeen, Kenneth Ladd; Lasky, Ginger; Leiker, Merced Marie; Pang, Manhui; Personius, Kirkwood Ely; Troen, Bruce Robert

2018-03-14

Sarcopenia and frailty are highly prevalent in older individuals, increasing the risk of disability and loss of independence. High intensity interval training (HIIT) may provide a robust intervention for both sarcopenia and frailty by achieving both strength and endurance benefits with lower time commitments than other exercise regimens. To better understand the impacts of HIIT during aging, we compared 24-month-old C57BL/6J sedentary mice with those that were administered 10-minute uphill treadmill HIIT sessions three times per week over 16 weeks. Baseline and end point assessments included body composition, physical performance, and frailty based on criteria from the Fried physical frailty scale. HIIT-trained mice demonstrated dramatic improvement in grip strength (HIIT 10.9% vs -3.9% in sedentary mice), treadmill endurance (32.6% vs -2.0%), and gait speed (107.0% vs 39.0%). Muscles from HIIT mice also exhibited greater mass, larger fiber size, and an increase in mitochondrial biomass. Furthermore, HIIT exercise led to a dramatic reduction in frailty scores in five of six mice that were frail or prefrail at baseline, with four ultimately becoming nonfrail. The uphill treadmill HIIT exercise sessions were well tolerated by aged mice and led to performance gains, improvement in underlying muscle physiology, and reduction in frailty.

Effect of age on susceptibility to Salmonella Typhimurium infection in C57BL/6 mice.

PubMed

Ren, Zhihong; Gay, Raina; Thomas, Adam; Pae, Munkyong; Wu, Dayong; Logsdon, Lauren; Mecsas, Joan; Meydani, Simin Nikbin

2009-12-01

Ageing is associated with a decline in immune function, which predisposes the elderly to a higher incidence of infections. Information on the mechanism of the age-related increase in susceptibility to Salmonella enterica serovar Typhimurium (S. Typhimurium) is limited. In particular, little is known regarding the involvement of the immune response in this age-related change. We employed streptomycin (Sm)-pretreated C57BL/6 mice to develop a mouse model that would demonstrate age-related differences in susceptibility and immune response to S. Typhimurium. In this model, old mice inoculated orally with doses of 3 x 10(8) or 1 x 10(6) c.f.u. S. Typhimurium had significantly greater S. Typhimurium colonization in the ileum, colon, Peyer's patches, spleen and liver than young mice. Old mice had significantly higher weight loss than young mice on days 1 and 2 post-infection. In response to S. Typhimurium infection, old mice failed to increase ex vivo production of IFN-gamma and TNF-alpha in the spleen and mesenteric lymph node cells to the same degree as observed in young mice; this was associated with their inability to maintain the presence of neutrophils and macrophages at a 'youthful' level. These results indicate that Sm-pretreated C57BL/6 old mice are more susceptible to S. Typhimurium infection than young mice, which might be due to impaired IFN-gamma and TNF-alpha production as well as a corresponding change in the number of neutrophils and macrophages in response to S. Typhimurium infection compared to young mice.

Astaxanthin affects oxidative stress and hyposalivation in aging mice

PubMed Central

Kuraji, Manatsu; Matsuno, Tomonori; Satoh, Tazuko

2016-01-01

Oral dryness, a serious problem for the aging Japanese society, is induced by aging-related hyposalivation and causes dysphagia, dysgeusia, inadaptation of dentures, and growth of oral Candida albicans. Oxidative stress clearly plays a role in decreasing saliva secretion and treatment with antioxidants such astaxanthin supplements may be beneficial. Therefore, we evaluated the effects of astaxanthin on the oral saliva secretory function of aging mice. The saliva flow increased in astaxanthin-treated mice 72 weeks after administration while that of the control decreased by half. The plasma d-ROMs values of the control but not astaxanthin-treated group measured before and 72 weeks after treatment increased. The diacron-reactive oxygen metabolites (d-ROMs) value of astaxanthin-treated mice 72 weeks after treatment was significantly lower than that of the control group was. The plasma biological antioxidative potential (BAP) values of the control but not astaxanthin-treated mice before and 72 weeks after treatment decreased. Moreover, the BAP value of the astaxanthin-treated group 72 weeks after treatment was significantly higher than that of the control was. Furthermore, the submandibular glands of astaxanthin-treated mice had fewer inflammatory cells than the control did. Specifically, immunofluorescence revealed a significantly large aquaporin-5 positive cells in astaxanthin-treated mice. Our results suggest that astaxanthin treatment may prevent age-related decreased saliva secretion. PMID:27698533

Knock-in reporter mice demonstrate that DNA repair by non-homologous end joining declines with age.

PubMed

Vaidya, Amita; Mao, Zhiyong; Tian, Xiao; Spencer, Brianna; Seluanov, Andrei; Gorbunova, Vera

2014-07-01

Accumulation of genome rearrangements is a characteristic of aged tissues. Since genome rearrangements result from faulty repair of DNA double strand breaks (DSBs), we hypothesized that DNA DSB repair becomes less efficient with age. The Non-Homologous End Joining (NHEJ) pathway repairs a majority of DSBs in vertebrates. To examine age-associated changes in NHEJ, we have generated an R26NHEJ mouse model in which a GFP-based NHEJ reporter cassette is knocked-in to the ROSA26 locus. In this model, NHEJ repair of DSBs generated by the site-specific endonuclease, I-SceI, reconstitutes a functional GFP gene. In this system NHEJ efficiency can be compared across tissues of the same mouse and in mice of different age. Using R26NHEJ mice, we found that NHEJ efficiency was higher in the skin, lung, and kidney fibroblasts, and lower in the heart fibroblasts and brain astrocytes. Furthermore, we observed that NHEJ efficiency declined with age. In the 24-month old animals compared to the 5-month old animals, NHEJ efficiency declined 1.8 to 3.8-fold, depending on the tissue, with the strongest decline observed in the skin fibroblasts. The sequence analysis of 300 independent NHEJ repair events showed that, regardless of age, mice utilize microhomology sequences at a significantly higher frequency than expected by chance. Furthermore, the frequency of microhomology-mediated end joining (MMEJ) events increased in the heart and lung fibroblasts of old mice, suggesting that NHEJ becomes more mutagenic with age. In summary, our study provides a versatile mouse model for the analysis of NHEJ in a wide range of tissues and demonstrates that DNA repair by NHEJ declines with age in mice, which could provide a mechanism for age-related genomic instability and increased cancer incidence with age.

The nigrostriatal dopamine system of aging GFRα-1 heterozygous mice: neurochemistry, morphology and behavior

PubMed Central

Zaman, Vandana; Boger, Heather A.; Granholm, Ann-Charlotte; Rohrer, Baerbel; Moore, Alfred; Buhusi, Mona; Gerhardt, Greg A.; Hoffer, Barry J.; Middaugh, Lawrence D.

2009-01-01

Given the established importance of glial cell line-derived neurotrophic factor (GDNF) in maintaining dopaminergic neurotransmitter systems, the nigrostriatal system and associated behaviors of mice with genetic reduction of its high-affinity receptor, GDNF receptor (GFR)α-1 (GFRα-1+/−), were compared with wild-type controls. Motor activity and the stimulatory effects of a dopamine (DA) D1 receptor agonist (SKF 82958) were assessed longitudinally at 8 and 18 months of age. Monoamine concentrations and dopaminergic nerve terminals in the striatum and the number of dopaminergic neurons in the substantia nigra (SN) were assessed. The results support the importance of GFRα-1 in maintaining normal function of the nigrostriatal dopaminergic system, with deficits being observed for GFRα-1+/− mice at both ages. Motor activity was lower and the stimulatory effects of the DA agonist were enhanced for the older GFRα-1+/− mice. DA in the striatum was reduced in the GFRα-1+/− mice at both ages, and tyrosine hydroxylase-positive cell numbers in the SN were reduced most substantially in the older GFRα-1+/− mice. The combined behavioral, pharmacological probe, neurochemical and morphological measures provide evidence of abnormalities in GFRα-1+/− mice that are indicative of an exacerbated aging-related decline in dopaminergic system function. The noted deficiencies, in turn, suggest that GFRα-1 is necessary for GDNF to maintain normal function of the nigrostriatal dopaminergic system. Although the precise mechanism(s) for the aging-related changes in the dopaminergic system remain to be established, the present study clearly establishes that genetic reductions in GFRα-1 can contribute to the degenerative changes observed in this system during the aging process. PMID:18973577

A Larger Social Network Enhances Novel Object Location Memory and Reduces Hippocampal Microgliosis in Aged Mice.

PubMed

Smith, Bryon M; Yao, Xinyue; Chen, Kelly S; Kirby, Elizabeth D

2018-01-01

The mammalian hippocampus shows marked decline in function with aging across many species, including humans and laboratory rodent models. This decline frequently manifests in memory impairments that occur even in the absence of dementia pathology. In humans, a number of factors correlate with preserved hippocampal memory in aging, such as exercise, cognitive stimulation and number of social ties. While interventional studies and animal models clearly indicate that exercise and cognitive stimulation lead to hippocampal preservation, there is relatively little research on whether a decline in social ties leads to cognitive decline or vice versa. Even in animal studies of environmental enrichment in aging, the focus typically falls on physical enrichment such as a rotating cast of toys, rather than the role of social interactions. The present studies investigated the hypothesis that a greater number of social ties in aging mice would lead to improved hippocampal function. Aged, female C57/Bl6 mice were housed for 3 months in pairs or large groups (7 mice per cage). Group-housed mice showed greater novel object location memory and stronger preference for a spatial navigation strategy in the Barnes maze, though no difference in escape latency, compared to pair-housed mice. Group-housed mice did not differ from pair-housed mice in basal corticosterone levels or adult hippocampal neurogenesis. Group-housed mice did, however, show reduced numbers of Iba1/CD68+ microglia in the hippocampus. These findings suggest that group housing led to better memory function and reduced markers of neuroinflammation in aged mice. More broadly, they support a causative link between social ties and hippocampal function, suggesting that merely having a larger social network can positively influence the aging brain. Future research should address the molecular mechanisms by which a greater number of social ties alters hippocampal function.

A Larger Social Network Enhances Novel Object Location Memory and Reduces Hippocampal Microgliosis in Aged Mice

PubMed Central

Smith, Bryon M.; Yao, Xinyue; Chen, Kelly S.; Kirby, Elizabeth D.

2018-01-01

The mammalian hippocampus shows marked decline in function with aging across many species, including humans and laboratory rodent models. This decline frequently manifests in memory impairments that occur even in the absence of dementia pathology. In humans, a number of factors correlate with preserved hippocampal memory in aging, such as exercise, cognitive stimulation and number of social ties. While interventional studies and animal models clearly indicate that exercise and cognitive stimulation lead to hippocampal preservation, there is relatively little research on whether a decline in social ties leads to cognitive decline or vice versa. Even in animal studies of environmental enrichment in aging, the focus typically falls on physical enrichment such as a rotating cast of toys, rather than the role of social interactions. The present studies investigated the hypothesis that a greater number of social ties in aging mice would lead to improved hippocampal function. Aged, female C57/Bl6 mice were housed for 3 months in pairs or large groups (7 mice per cage). Group-housed mice showed greater novel object location memory and stronger preference for a spatial navigation strategy in the Barnes maze, though no difference in escape latency, compared to pair-housed mice. Group-housed mice did not differ from pair-housed mice in basal corticosterone levels or adult hippocampal neurogenesis. Group-housed mice did, however, show reduced numbers of Iba1/CD68+ microglia in the hippocampus. These findings suggest that group housing led to better memory function and reduced markers of neuroinflammation in aged mice. More broadly, they support a causative link between social ties and hippocampal function, suggesting that merely having a larger social network can positively influence the aging brain. Future research should address the molecular mechanisms by which a greater number of social ties alters hippocampal function. PMID:29904345

Every-other-day feeding extends lifespan but fails to delay many symptoms of aging in mice.

PubMed

Xie, Kan; Neff, Frauke; Markert, Astrid; Rozman, Jan; Aguilar-Pimentel, Juan Antonio; Amarie, Oana Veronica; Becker, Lore; Brommage, Robert; Garrett, Lillian; Henzel, Kristin S; Hölter, Sabine M; Janik, Dirk; Lehmann, Isabelle; Moreth, Kristin; Pearson, Brandon L; Racz, Ildiko; Rathkolb, Birgit; Ryan, Devon P; Schröder, Susanne; Treise, Irina; Bekeredjian, Raffi; Busch, Dirk H; Graw, Jochen; Ehninger, Gerhard; Klingenspor, Martin; Klopstock, Thomas; Ollert, Markus; Sandholzer, Michael; Schmidt-Weber, Carsten; Weiergräber, Marco; Wolf, Eckhard; Wurst, Wolfgang; Zimmer, Andreas; Gailus-Durner, Valerie; Fuchs, Helmut; Hrabě de Angelis, Martin; Ehninger, Dan

2017-07-24

Dietary restriction regimes extend lifespan in various animal models. Here we show that longevity in male C57BL/6J mice subjected to every-other-day feeding is associated with a delayed onset of neoplastic disease that naturally limits lifespan in these animals. We compare more than 200 phenotypes in over 20 tissues in aged animals fed with a lifelong every-other-day feeding or ad libitum access to food diet to determine whether molecular, cellular, physiological and histopathological aging features develop more slowly in every-other-day feeding mice than in controls. We also analyze the effects of every-other-day feeding on young mice on shorter-term every-other-day feeding or ad libitum to account for possible aging-independent restriction effects. Our large-scale analysis reveals overall only limited evidence for a retardation of the aging rate in every-other-day feeding mice. The data indicate that every-other-day feeding-induced longevity is sufficiently explained by delays in life-limiting neoplastic disorders and is not associated with a more general slowing of the aging process in mice.Dietary restriction can extend the life of various model organisms. Here, Xie et al. show that intermittent periods of fasting achieved through every-other-day feeding protect mice against neoplastic disease but do not broadly delay organismal aging in animals.

Paternal Aging Affects Behavior in Pax6 Mutant Mice: A Gene/Environment Interaction in Understanding Neurodevelopmental Disorders.

PubMed

Yoshizaki, Kaichi; Furuse, Tamio; Kimura, Ryuichi; Tucci, Valter; Kaneda, Hideki; Wakana, Shigeharu; Osumi, Noriko

2016-01-01

Neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit and hyperactivity disorder (ADHD) have increased over the last few decades. These neurodevelopmental disorders are characterized by a complex etiology, which involves multiple genes and gene-environmental interactions. Various genes that control specific properties of neural development exert pivotal roles in the occurrence and severity of phenotypes associated with neurodevelopmental disorders. Moreover, paternal aging has been reported as one of the factors that contribute to the risk of ASD and ADHD. Here we report, for the first time, that paternal aging has profound effects on the onset of behavioral abnormalities in mice carrying a mutation of Pax6, a gene with neurodevelopmental regulatory functions. We adopted an in vitro fertilization approach to restrict the influence of additional factors. Comprehensive behavioral analyses were performed in Sey/+ mice (i.e., Pax6 mutant heterozygotes) born from in vitro fertilization of sperm taken from young or aged Sey/+ fathers. No body weight changes were found in the four groups, i.e., Sey/+ and wild type (WT) mice born to young or aged father. However, we found important differences in maternal separation-induced ultrasonic vocalizations of Sey/+ mice born from young father and in the level of hyperactivity of Sey/+ mice born from aged fathers in the open-field test, respectively, compared to WT littermates. Phenotypes of anxiety were observed in both genotypes born from aged fathers compared with those born from young fathers. No significant difference was found in social behavior and sensorimotor gating among the four groups. These results indicate that mice with a single genetic risk factor can develop different phenotypes depending on the paternal age. Our study advocates for serious considerations on the role of paternal aging in breeding strategies for animal studies.

Adipose stem cells’ antagonism in glycosylation of D-galactose-induced skin aging of nude mice and its skin recovery function

PubMed Central

Wang, Haiying; Wei, Shuyue; Xue, Xinxin; You, Yuntian; Ma, Qiang

2016-01-01

This study aims to discuss adipose stem cells’ (ASCs) antagonism in glycosylation of D-galactose-induced skin aging of nude mice and its skin recovery function; the study also aims to explore a new mechanism of anti-aging to provide clinical anti-aging therapy with new thoughts and methods. We selected 40 healthy specific pathogen-free (SPF) nude mice and divided them randomly into four groups which were: blank control group; D-galactose + phosphate buffer saline (PBS) group; D-galactose + ASCs treatment group; and D-galactose + aminoguanidine (AG) group. Results showed that the superoxide dismutase (SOD) level of mice in the D-galactose-induced model group (87.15 ± 4.95 U/g) decreased significantly compared with that of control group (146.21 ± 4.76 U/g), while malonaldehyde (MDA) level of mice in D-galactose induced model group (11.12 ± 2.08 nmol/mg) increased significantly compared with that of control group (5.46 ± 2.05 nmol/mg) (P <0.05); thus D-galactose induced sub-acutely aging mice models were duplicated successfully. Results also indicated that transplantation of ASCs could reverse expression of aging-related biomarkers such as MDA, SOD, and advanced glycosylation end products (AGEs); hematoxylin and eosin (HE) staining showed that thickness of the dermis layer as well as the collagen content of mice in the D-galactose-induced model group increased significantly after ASC transplantation compared with that of control group. In addition, immunohistochemical assay showed that expression quantity of CD31 and vascular endothelial growth factor (VEGF) of mice in the D-galactose-induced model group increased significantly after ASC transplantation compared with that of control group. In conclusion, ASCs can trace cell distribution successfully through bioluminescence, and they survive for a short time in the skin after transplantation, which provides a basis for the application of ASC transplantation in clinical practices. Moreover, ASCs can control

Disuse osteopenia induced by botulinum toxin is similar in skeletally mature young and aged female C57BL/6J mice.

PubMed

Vegger, Jens Bay; Brüel, Annemarie; Brent, Mikkel Bo; Thomsen, Jesper Skovhus

2018-03-01

Osteopenia and osteoporosis predominately occur in the fully grown skeleton. However, it is unknown whether disuse osteopenia in skeletally mature, but growing, mice resembles that of fully grown mice. Twenty-four 16-week-old (young) and eighteen 44-week-old (aged) female C57BL/6J mice were investigated. Twelve young and nine aged mice were injected with botulinum toxin in one hind limb; the remaining mice served as controls. The mice were euthanized after 3 weeks of disuse. The femora were scanned by micro-computed tomography (µCT) and bone strength was determined by mechanically testing the femoral mid-diaphysis and neck. At the distal femoral metaphysis, the loss of trabecular bone volume fraction (BV/TV) differed between the young and aged mice. However, at the distal femoral epiphysis, no age-dependent differences were observed. Thinning of the trabeculae was not affected by the age of the mice at either the distal femoral metaphysis or the epiphysis. Furthermore, the aged mice lost more bone strength at the femoral mid-diaphysis, but not at the femoral neck, compared to the young mice. In general, the bone loss induced by botulinum toxin did not differ substantially between young and aged mice. Therefore, the loss of bone in young mice resembles that of aged mice, even though they are not fully grown.

Resilience in Aging Mice.

PubMed

Kirkland, James L; Stout, Michael B; Sierra, Felipe

2016-11-01

Recently discovered interventions that target fundamental aging mechanisms have been shown to increase life span in mice and other species, and in some cases, these same manipulations have been shown to enhance health span and alleviate multiple age-related diseases and conditions. Aging is generally associated with decreases in resilience, the capacity to respond to or recover from clinically relevant stresses such as surgery, infections, or vascular events. We hypothesize that the age-related increase in susceptibility to those diseases and conditions is driven by or associated with the decrease in resilience. Thus, a test for resilience at middle age or even earlier could represent a surrogate approach to test the hypothesis that an intervention delays the process of aging itself. For this, animal models to test resilience accurately and predictably are needed. In addition, interventions that increase resilience might lead to treatments aimed at enhancing recovery following acute illnesses, or preventing poor outcomes from medical interventions in older, prefrail subjects. At a meeting of basic researchers and clinicians engaged in research on mechanisms of aging and care of the elderly, the merits and drawbacks of investigating effects of interventions on resilience in mice were considered. Available and potential stressors for assessing physiological resilience as well as the notion of developing a limited battery of such stressors and how to rank them were discussed. Relevant ranking parameters included value in assessing general health (as opposed to focusing on a single physiological system), ease of use, cost, reproducibility, clinical relevance, and feasibility of being repeated in the same animal longitudinally. During the discussions it became clear that, while this is an important area, very little is known or established. Much more research is needed in the near future to develop appropriate tests of resilience in animal models within an aging context

Effects of ethanol on immune response in the brain: region-specific changes in aged mice.

PubMed

Kane, Cynthia J M; Phelan, Kevin D; Douglas, James C; Wagoner, Gail; Johnson, Jennifer Walker; Xu, Jihong; Drew, Paul D

2013-05-23

Alcohol abuse has dramatic effects on the health of the elderly. Recent studies indicate that ethanol increases immune activity in younger animals and that some of these proinflammatory molecules alter alcohol consumption and addiction. However, the effects of alcohol on immune activation in aged animals have not been thoroughly investigated. We compared the effects of ethanol on chemokine and cytokine expression in the hippocampus, cerebellum, and cerebral cortex of aged C57BL/6 mice. Mice were treated via gavage with 6 g/kg ethanol for 10 days and tissue was harvested 1 day post-treatment. Ethanol selectively increased mRNA levels of the chemokine (C-C motif) ligand 2/monocyte chemotactic protein-1 in the hippocampus and cerebellum, but not in the cortex of aged mice relative to control animals. In this paradigm, ethanol did not affect mRNA levels of the cytokines IL-6 or TNF-α in any of these brain regions in aged animals. Collectively, these data indicate a region-specific susceptibility to ethanol regulation of neuroinflammatory and addiction-related molecules in aged mice. These studies could have important implications concerning alcohol-induced neuropathology and alcohol addiction in the elderly.

Age-related Changes in the Hepatic Microcirculation in Mice

PubMed Central

Ito, Yoshiya; Sørensen, Karen K.; Bethea, Nancy W.; Svistounov, Dmitri; McCuskey, Margaret K.; Smedsrød, Bård H.; McCuskey, Robert S.

2007-01-01

Aging of the liver is associated with impaired metabolism of drugs, adverse drug interactions, and susceptibility to toxins. Since reduced hepatic blood flow is suspected to contribute this impairment, we examined age-related alterations in hepatic microcirculation.. Livers of C57Bl/6 mice were examined at 0.8 (pre-pubertal), 3 (young adult), 14 (middle-aged) and 27 (senescent) months of age using in vivo and electron microscopic methods. The results demonstrated a 14% reduction in the numbers of perfused sinusoids between 0.8 and 27 month mice associated with 35% reduction in sinusoidal blood flow. This was accompanied by an inflammatory response evidenced by a 5-fold increase in leukocyte adhesion in 27 month mice, up-regulated expression of ICAM-1, and increases in intrahepatic macrophages. Sinusoidal diameter decreased 6-10%. Liver sinusoidal endothelial cell (LSEC) dysfunction was seen as early as 14 months when there was a 3-fold increase in the numbers of swollen LSEC. The endocytotic capacity of LSEC also was found to be reduced in older animals. The sinusoidal endothelium in 27 month old mice exhibited pseudocapillarization. In conclusion, the results suggest that leukocyte accumulation in the sinusoids and narrowing of sinusoidal lumens due to pseudocapillarization and dysfunction of LSEC reduce sinusoidal blood flow in aged livers. PMID:17582718

Dihydrocapsiate improved age-associated impairments in mice by increasing energy expenditure.

PubMed

Ohyama, Kana; Suzuki, Katsuya

2017-11-01

Metabolic dysfunction is associated with aging and results in age-associated chronic diseases, including type 2 diabetes mellitus, cardiovascular disease, and stroke. Hence, there has been a focus on increasing energy expenditure in aged populations to protect them from age-associated diseases. Dihydrocapsiate (DCT) is a compound that belongs to the capsinoid family. Capsinoids are capsaicin analogs that are found in nonpungent peppers and increase whole body energy expenditure. However, their effect on energy expenditure has been reported only in young populations, and to date the effectiveness of DCT in increasing energy expenditure in aged populations has not been investigated. In this study, we investigated whether DCT supplementation in aged mice improves age-associated impairments. We obtained 5-wk-old and 1-yr-old male C57BL/6J mice and randomly assigned the aged mice to two groups, resulting in a total of three groups: 1 ) young mice, 2 ) old mice, and 3 ) old mice supplemented with 0.3% DCT. After 12 wk of supplementation, blood and tissue samples were collected and analyzed. DCT significantly suppressed age-associated fat accumulation, adipocyte hypertrophy, and liver steatosis. In addition, the DCT treatment dramatically suppressed age-associated increases in hepatic inflammation, immune cell infiltration, and oxidative stress. DCT exerted these suppression effects by increasing energy expenditure linked to upregulation of both the oxidative phosphorylation gene program and fatty acid oxidation in skeletal muscle. These results indicate that DCT efficiently improves age-associated impairments, including liver steatosis and inflammation, in part by increasing energy expenditure via activation of the fat oxidation pathway in skeletal muscle. Copyright © 2017 the American Physiological Society.

Impaired CXCR4 Expression and Cell Engraftment of Bone Marrow-derived Cells from Aged Atherogenic Mice

PubMed Central

Xu, Qiyuan; Wang, Jian’An; He, Jinlin; Zhou, Mingsheng; Adi, Jennipher; Webster, Keith A; Yu, Hong

2011-01-01

Objectives Reduced numbers and activity of circulating progenitor cells are associated with aging and have been linked with coronary artery disease. To determine the impact of aging and atherosclerotic disease on the chemotaxic activity of bone marrow derived cells (BMCs), we examined CXCR4 surface expression on BMCs from aged and atherosclerotic mice. Methods CXCR4 expression and cellular mobility were compared between BMCs of young (6-week old) ApoE null mice (ApoE−/−) and aged ApoE−/− mice that had been fed with a high-fat, high-cholesterol diet for 6-months. Results Age and atherosclerosis correlated with significantly lower surface expression of CXCR4 that was less inducible by calcium. The impaired calcium response was associated with defective calcium influx and was partially recovered by treatment with the calcium ionophore ionomycin. ApoE−/− mice fed high fat diet for 6-months had defective CXCR4 expression and SDF-1 regulation that is equivalent to that of 24-month old wild type mice. BMCs from aged, atherogenic ApoE−/− mice also displayed defective homing to SDF-1, and the animals had lower serum and bone marrow levels of SDF-1. Conclusion Evolution of atherosclerosis in ApoE−/− mice is paralleled by progressive loss of mobility of BMCs with reductions of CXCR4 expression, and reduced levels of SDF-1 in both serum and bone marrow. These changes mute the homing capability of BMCs and may contribute to the progression of atherosclerosis in this model. PMID:21855069

Motor Performance is Impaired Following Vestibular Stimulation in Ageing Mice.

PubMed

Tung, Victoria W K; Burton, Thomas J; Quail, Stephanie L; Mathews, Miranda A; Camp, Aaron J

2016-01-01

Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5-6, 8-9 and 27-28 months were tested using a combination of standard (such as grip strength and rotarod) and newly-developed behavioral tests (including balance beam and walking trajectory tests with a vestibular stimulus). In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2-3 Hz) and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip (FS) from the beam. Furthermore, aged mice (27-28 months) that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13 and 27-28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13 and 27-28 months. this study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioral changes in task performance were observed.

Experimental febrile seizures induce age-dependent structural plasticity and improve memory in mice.

PubMed

Tao, K; Ichikawa, J; Matsuki, N; Ikegaya, Y; Koyama, R

2016-03-24

Population-based studies have demonstrated that children with a history of febrile seizure (FS) perform better than age-matched controls at hippocampus-dependent memory tasks. Here, we report that FSs induce two distinct structural reorganizations in the hippocampus and bidirectionally modify future learning abilities in an age-dependent manner. Compared with age-matched controls, adult mice that had experienced experimental FSs induced by hyperthermia (HT) on postnatal day 14 (P14-HT) performed better in a cognitive task that requires dentate granule cells (DGCs). The enhanced memory performance correlated with an FS-induced persistent increase in the density of large mossy fiber terminals (LMTs) of the DGCs. The memory enhancement was not observed in mice that had experienced HT-induced seizures at P11 which exhibited abnormally located DGCs in addition to the increased LMT density. The ectopic DGCs of the P11-HT mice were abolished by the diuretic bumetanide, and this pharmacological treatment unveiled the masked memory enhancement. Thus, this work provides a novel basis for age-dependent structural plasticity in which FSs influence future brain function. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

IL-1 receptor-antagonist (IL-1Ra) knockout mice show anxiety-like behavior by aging.

PubMed

Wakabayashi, Chisato; Numakawa, Tadahiro; Odaka, Haruki; Ooshima, Yoshiko; Kiyama, Yuji; Manabe, Toshiya; Kunugi, Hiroshi; Iwakura, Yoichiro

2015-07-10

Interleukin 1 (IL-1) plays a critical role in stress responses, and its mRNA is induced in the brain by restraint stress. Previously, we reported that IL-1 receptor antagonist (IL-1Ra) knockout (KO) mice, which lacked IL-1Ra molecules that antagonize the IL-1 receptor, showed anti-depression-like behavior via adrenergic modulation at the age of 8 weeks. Here, we report that IL-1Ra KO mice display an anxiety-like phenotype that is induced spontaneously by aging in the elevated plus-maze (EPM) test. This anxiety-like phenotype was improved by the administration of diazepam. The expression of the anxiety-related molecule glucocorticoid receptor (GR) was significantly reduced in 20-week-old but not in 11-week-old IL-1Ra KO mice compared to wild-type (WT) littermates. The expression of the mineralocorticoid receptor (MR) was not altered between IL-1Ra KO mice and WT littermates at either 11 or 20 weeks old. Analysis of monoamine concentration in the hippocampus revealed that tryptophan, the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), and the dopamine metabolite homovanillic acid (HVA) were significantly increased in 20-week-old IL-1Ra KO mice compared to littermate WT mice. These findings strongly suggest that the anxiety-like behavior observed in older mice was caused by the complicated alteration of monoamine metabolism and/or GR expression in the hippocampus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Aging-associated oxidative stress inhibits liver progenitor cell activation in mice

PubMed Central

Wang, Bei; Zhou, Hong; Dang, Shipeng; Shi, Yufang; Hao, Li; Luo, Qingquan; Jin, Min; Zhou, Qianjun; Zhang, Yanyun

2017-01-01

Recent studies have discovered aging-associated changes of adult stem cells in various tissues and organs, which potentially contribute to the organismal aging. However, aging-associated changes of liver progenitor cells (LPCs) remain elusive. Employing young (2-month-old) and old (24-month-old) mice, we found diverse novel alterations in LPC activation during aging. LPCs in young mice could be activated and proliferate upon liver injury, whereas the counterparts in old mice failed to respond and proliferate, leading to the impaired liver regeneration. Surprisingly, isolated LPCs from young and old mice did not exhibit significant difference in their clonogenic and proliferative capacity. Later, we uncovered that the decreased activation and proliferation of LPCs were due to excessive reactive oxygen species produced by neutrophils infiltrated into niche, which was resulted from chemokine production from activated hepatic stellate cells during aging. This study demonstrates aging-associated changes in LPC activation and reveals critical roles for the stem cell niche, including neutrophils and hepatic stellate cells, in the negative regulation of LPCs during aging. PMID:28458256

Aging-associated oxidative stress inhibits liver progenitor cell activation in mice.

PubMed

Cheng, Yiji; Wang, Xue; Wang, Bei; Zhou, Hong; Dang, Shipeng; Shi, Yufang; Hao, Li; Luo, Qingquan; Jin, Min; Zhou, Qianjun; Zhang, Yanyun

2017-04-29

Recent studies have discovered aging-associated changes of adult stem cells in various tissues and organs, which potentially contribute to the organismal aging. However, aging-associated changes of liver progenitor cells (LPCs) remain elusive. Employing young (2-month-old) and old (24-month-old) mice, we found diverse novel alterations in LPC activation during aging. LPCs in young mice could be activated and proliferate upon liver injury, whereas the counterparts in old mice failed to respond and proliferate, leading to the impaired liver regeneration. Surprisingly, isolated LPCs from young and old mice did not exhibit significant difference in their clonogenic and proliferative capacity. Later, we uncovered that the decreased activation and proliferation of LPCs were due to excessive reactive oxygen species produced by neutrophils infiltrated into niche, which was resulted from chemokine production from activated hepatic stellate cells during aging. This study demonstrates aging-associated changes in LPC activation and reveals critical roles for the stem cell niche, including neutrophils and hepatic stellate cells, in the negative regulation of LPCs during aging.

Chronic exercise reduces hypothalamic transforming growth factor-β1 in middle-aged obese mice.

PubMed

Silva, Vagner R R; Katashima, Carlos K; Lenhare, Luciene; Silva, Carla G B; Morari, Joseane; Camargo, Rafael L; Velloso, Licio A; Saad, Mario A; da Silva, Adelino S R; Pauli, Jose Rodrigo; Ropelle, Eduardo Rochete

2017-08-28

Obesity and aging are associated with hypothalamic inflammation, hyperphagia and abnormalities in the thermogenesis control. It has been demonstrated that the association between aging and obesity induces hypothalamic inflammation and metabolic disorders, at least in part, through the atypical hypothalamic transforming growth factor-β (TGF-β1). Physical exercise has been used to modulate several metabolic parameters. Thus, the aim of this study was to evaluate the impact of chronic exercise on TGF-β1 expression in the hypothalamus of Middle-Aged mice submitted to a one year of high-fat diet (HFD) treatment. We observed that long-term of HFD-feeding induced hypothalamic TGF-β1 accumulation, potentiated the hypothalamic inflammation, body weight gain and defective thermogenesis of Middle-Aged mice when compared to Middle-Aged animals fed on chow diet. As expected, chronic exercise induced negative energy balance, reduced food consumption and increasing the energy expenditure, which promotes body weight loss. Interestingly, exercise training reduced the TGF-β1 expression and IkB-α ser32 phosphorylation in the hypothalamus of Middle-Aged obese mice. Taken together our study demonstrated that chronic exercise suppressed the TGF-β1/IkB-α axis in the hypothalamus and improved the energy homeostasis in an animal model of obesity-associated to aging.

Chronic exercise reduces hypothalamic transforming growth factor-β1 in middle-aged obese mice

PubMed Central

Silva, Vagner R. R.; Katashima, Carlos K.; Lenhare, Luciene; Silva, Carla G. B.; Morari, Joseane; Camargo, Rafael L.; Velloso, Licio A.; Saad, Mario A.; da Silva, Adelino S. R.; Pauli, Jose Rodrigo; Ropelle, Eduardo Rochete

2017-01-01

Obesity and aging are associated with hypothalamic inflammation, hyperphagia and abnormalities in the thermogenesis control. It has been demonstrated that the association between aging and obesity induces hypothalamic inflammation and metabolic disorders, at least in part, through the atypical hypothalamic transforming growth factor-β (TGF-β1). Physical exercise has been used to modulate several metabolic parameters. Thus, the aim of this study was to evaluate the impact of chronic exercise on TGF-β1 expression in the hypothalamus of Middle-Aged mice submitted to a one year of high-fat diet (HFD) treatment. We observed that long-term of HFD-feeding induced hypothalamic TGF-β1 accumulation, potentiated the hypothalamic inflammation, body weight gain and defective thermogenesis of Middle-Aged mice when compared to Middle-Aged animals fed on chow diet. As expected, chronic exercise induced negative energy balance, reduced food consumption and increasing the energy expenditure, which promotes body weight loss. Interestingly, exercise training reduced the TGF-β1 expression and IkB-α ser32 phosphorylation in the hypothalamus of Middle-Aged obese mice. Taken together our study demonstrated that chronic exercise suppressed the TGF-β1/IkB-α axis in the hypothalamus and improved the energy homeostasis in an animal model of obesity-associated to aging. PMID:28854149

[Effects of chrysalis oil on learning, memory and oxidative stress in D-galactose-induced ageing model of mice].

PubMed

Chen, Weiping; Yang, Qiongjie; Wei, Xing

2013-11-01

To investigate the effects of chrysalis oil on learning, memory and oxidative stress in D-galactose-induced ageing model of mice. Mice were injected intraperitoneally with D-galactose daily and received chrysalis oil intragastrically simultaneously for 30 d. Then mice underwent space navigation test and spatial probe test, superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) activity and malondialdehyde (MDA) contents in mouse brain were measured. Compared to model group, escape latency in mice treated with 6 ml/kg*d chrysalis oil was significantly shorter (P<0.05), crossing times in 12 ml/kg*d group and 6 ml/kg*d group treated with chrysalis oil were significantly increased (P<0.05). Chrysalis oil treatment (12ml/kg*d) significantly increased SOD and GSH-PX activity and reduced MDA contents in brain of D-galactose-induced aging mice. Chrysalis oil can improve the ability of learning and memory in D-galactose-induced aging mice, and inhibit peroxidation in brain tissue.

Adipose stem cells' antagonism in glycosylation of D-galactose-induced skin aging of nude mice and its skin recovery function.

PubMed

Wang, Haiying; Wei, Shuyue; Xue, Xinxin; You, Yuntian; Ma, Qiang

2016-09-01

This study aims to discuss adipose stem cells' (ASCs) antagonism in glycosylation of D-galactose-induced skin aging of nude mice and its skin recovery function; the study also aims to explore a new mechanism of anti-aging to provide clinical anti-aging therapy with new thoughts and methods. We selected 40 healthy specific pathogen-free (SPF) nude mice and divided them randomly into four groups which were: blank control group; D-galactose + phosphate buffer saline (PBS) group; D-galactose + ASCs treatment group; and D-galactose + aminoguanidine (AG) group. Results showed that the superoxide dismutase (SOD) level of mice in the D-galactose-induced model group (87.15 ± 4.95 U/g) decreased significantly compared with that of control group (146.21 ± 4.76 U/g), while malonaldehyde (MDA) level of mice in D-galactose induced model group (11.12 ± 2.08 nmol/mg) increased significantly compared with that of control group (5.46 ± 2.05 nmol/mg) (P <0.05); thus D-galactose induced sub-acutely aging mice models were duplicated successfully. Results also indicated that transplantation of ASCs could reverse expression of aging-related biomarkers such as MDA, SOD, and advanced glycosylation end products (AGEs); hematoxylin and eosin (HE) staining showed that thickness of the dermis layer as well as the collagen content of mice in the D-galactose-induced model group increased significantly after ASC transplantation compared with that of control group. In addition, immunohistochemical assay showed that expression quantity of CD31 and vascular endothelial growth factor (VEGF) of mice in the D-galactose-induced model group increased significantly after ASC transplantation compared with that of control group. In conclusion, ASCs can trace cell distribution successfully through bioluminescence, and they survive for a short time in the skin after transplantation, which provides a basis for the application of ASC transplantation in clinical practices. Moreover, ASCs can control

Aging exacerbates depressive-like behavior in mice in response to activation of the peripheral innate immune system.

PubMed

Godbout, Jonathan P; Moreau, Maïté; Lestage, Jacques; Chen, Jing; Sparkman, Nathan L; O'Connor, Jason; Castanon, Nathalie; Kelley, Keith W; Dantzer, Robert; Johnson, Rodney W

2008-09-01

Exposure to peripheral infections may be permissive to cognitive and behavioral complications in the elderly. We have reported that peripheral stimulation of the innate immune system with lipopolysaccharide (LPS) causes an exaggerated neuroinflammatory response and prolonged sickness behavior in aged BALB/c mice. Because LPS also causes depressive behavior, the purpose of this study was to determine whether aging is associated with an exacerbated depressive-like response. We confirmed that LPS (0.33 mg/kg intraperitoneal) induced a protracted sickness response in aged mice with reductions in locomotor and feeding activities 24 and 48 h postinjection, when young adults had fully recovered. When submitted to the forced swim test 24 h post-LPS, both young adult and aged mice exhibited an increased duration of immobility. However, when submitted to either the forced swim test or the tail suspension test 72 h post-LPS, an increased duration of immobility was evident only in aged mice. This prolonged depressive-like behavior in aged LPS-treated mice was associated with a more pronounced induction of peripheral and brain indoleamine 2,3-dioxygenase and a markedly higher turnover rate of brain serotonin (as measured by the ratio of 5-hydroxy-indoleacetic acid over 5-hydroxy-tryptamine) compared to young adult mice at 24 post-LPS injection. These results provide the first evidence that age-associated reactivity of the brain cytokine system could play a pathophysiological role in the increased prevalence of depression observed in the elderly.

Aberrant Bone Density in Aging Mice Lacking the Adenosine Transporter ENT1

PubMed Central

Hinton, David J.; McGee-Lawrence, Meghan E.; Lee, Moonnoh R.; Kwong, Hoi K.; Westendorf, Jennifer J.; Choi, Doo-Sup

2014-01-01

Adenosine is known to regulate bone production and resorption in humans and mice. Type 1 equilibrative nucleoside transporter (ENT1) is responsible for the majority of adenosine transport across the plasma membrane and is ubiquitously expressed in both humans and mice. However, the contribution of ENT1-mediated adenosine levels has not been studied in bone remodeling. With the recent identification of the importance of adenosine signaling in bone homeostasis, it is essential to understand the role of ENT1 to develop novel therapeutic compounds for bone disorders. Here we examined the effect of ENT1 deletion on bone density using X-ray, dual energy X-ray absorptiometry and micro-computerized tomography analysis. Our results show that bone density and bone mineral density is reduced in the lower thoracic and lumbar spine as well as the femur of old ENT1 null mice (>7 months) compared to wild-type littermates. Furthermore, we found increased mRNA expression of tartrate-resistant acid phosphatase (TRAP), an osteoclast marker, in isolated long bones from 10 month old ENT1 null mice compared to wild-type mice. In addition, aged ENT1 null mice displayed severe deficit in motor coordination and locomotor activity, which might be attributed to dysregulated bone density. Overall, our study suggests that ENT1-regulated adenosine signaling plays an essential role in lumbar spine and femur bone density. PMID:24586402

Reference memory, anxiety and estrous cyclicity in C57BL/6NIA mice are affected by age and sex.

PubMed

Frick, K M; Burlingame, L A; Arters, J A; Berger-Sweeney, J

2000-01-01

Age-related changes in learning and memory are common in rodents. However, direct comparisons of the effects of aging on learning and memory in both males and females are lacking. The present study examined whether memory deteriorates with increasing age in C57BL/6NIA mice, and whether age-related changes in learning and memory are similar in both sexes. Male and female mice (five, 17 and 25 months of age) were tested in a battery of behavioral tasks including the Morris water maze (spatial and non-spatial reference memory), simple odor discrimination (olfactory reference memory), plus maze (anxiety/exploration), locomotor activity, and basic reflexes. Five-month-old mice learned the water maze and odor discrimination tasks rapidly. Relative to five-month-old mice, 25-month-old mice exhibited impaired spatial and olfactory reference memory, but intact non-spatial reference memory. The spatial reference memory of 17-month-old mice was also impaired, but less so than 25-month mice. Seventeen-month-old mice exhibited intact non-spatial (visual and olfactory) reference memory. Five and 25-month-old mice had similar levels of plus maze exploration and locomotor activity, whereas 17-month-old mice were more active than both groups and were slightly less exploratory than five-month-old mice. Although sex differences were not observed in the five- and 25-month groups, 17-month-old females exhibited more impaired spatial reference memory and increased anxiety relative to 17-month-old males. Estrous cycling in females deteriorated significantly with increased age; all 25-month-old females had ceased cycling and 80% of 17-month-old females displayed either irregular or absent estrous cycling. This study is the first to directly compare age-related mnemonic decline in male and female mice. The results suggest that: (i) aged mice exhibit significant deficits in spatial and olfactory reference memory relative to young mice, whereas middle-aged mice exhibit only a moderate

Memory in aged mice is rescued by enhanced expression of the GluN2B subunit of the NMDA receptor

PubMed Central

Brim, B. L.; Haskell, R.; Awedikian, R.; Ellinwood, N.M.; Jin, L.; Kumar, A.; Foster, T.C.; Magnusson, K.

2012-01-01

The GluN2B subunit of the N-methyl-D-aspartate (NMDA) receptor shows age-related declines in expression across the frontal cortex and hippocampus. This decline is strongly correlated to age-related memory declines. This study was designed to determine if increasing GluN2B subunit expression in the frontal lobe or hippocampus would improve memory in aged mice. Mice were injected bilaterally with either the GluN2B vector, containing cDNA specific for the GluN2B subunit and enhanced Green Fluorescent Protein (eGFP); a control vector or vehicle. Spatial memory, cognitive flexibility, and associative memory were assessed using the Morris water maze. Aged mice, with increased GluN2B subunit expression, exhibited improved long-term spatial memory, comparable to young mice. However, memory was rescued on different days in the Morris water maze; early for hippocampal GluN2B subunit enrichment and later for the frontal lobe. A higher concentration of the GluN2B antagonist, Ro 25-6981, was required to impair long-term spatial memory in aged mice with enhanced GluN2B expression, as compared to aged controls, suggesting there was an increase in the number of GluN2B-containing NMDA receptors. In addition, hippocampal slices from aged mice with increased GluN2B subunit expression exhibited enhanced NMDA receptor-mediated excitatory post-synaptic potentials (EPSP). Treatment with Ro 25-6981 showed that a greater proportion of the NMDA receptor-mediated EPSP was due to the GluN2B subunit in these animals, as compared to aged controls. These results suggest that increasing the production of the GluN2B subunit in aged animals enhances memory and synaptic transmission. Therapies that enhance GluN2B subunit expression within the aged brain may be useful for ameliorating age-related memory declines. PMID:23103326

Age-Dependent Ocular Dominance Plasticity in Adult Mice

PubMed Central

Lehmann, Konrad; Löwel, Siegrid

2008-01-01

Background Short monocular deprivation (4 days) induces a shift in the ocular dominance of binocular neurons in the juvenile mouse visual cortex but is ineffective in adults. Recently, it has been shown that an ocular dominance shift can still be elicited in young adults (around 90 days of age) by longer periods of deprivation (7 days). Whether the same is true also for fully mature animals is not yet known. Methodology/Principal Findings We therefore studied the effects of different periods of monocular deprivation (4, 7, 14 days) on ocular dominance in C57Bl/6 mice of different ages (25 days, 90–100 days, 109–158 days, 208–230 days) using optical imaging of intrinsic signals. In addition, we used a virtual optomotor system to monitor visual acuity of the open eye in the same animals during deprivation. We observed that ocular dominance plasticity after 7 days of monocular deprivation was pronounced in young adult mice (90–100 days) but significantly weaker already in the next age group (109–158 days). In animals older than 208 days, ocular dominance plasticity was absent even after 14 days of monocular deprivation. Visual acuity of the open eye increased in all age groups, but this interocular plasticity also declined with age, although to a much lesser degree than the optically detected ocular dominance shift. Conclusions/Significance These data indicate that there is an age-dependence of both ocular dominance plasticity and the enhancement of vision after monocular deprivation in mice: ocular dominance plasticity in binocular visual cortex is most pronounced in young animals, reduced but present in adolescence and absent in fully mature animals older than 110 days of age. Mice are thus not basically different in ocular dominance plasticity from cats and monkeys which is an absolutely essential prerequisite for their use as valid model systems of human visual disorders. PMID:18769674

Motor Performance is Impaired Following Vestibular Stimulation in Ageing Mice

PubMed Central

Tung, Victoria W. K.; Burton, Thomas J.; Quail, Stephanie L.; Mathews, Miranda A.; Camp, Aaron J.

2016-01-01

Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5–6, 8–9 and 27–28 months were tested using a combination of standard (such as grip strength and rotarod) and newly-developed behavioral tests (including balance beam and walking trajectory tests with a vestibular stimulus). In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2–3 Hz) and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip (FS) from the beam. Furthermore, aged mice (27–28 months) that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13 and 27–28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13 and 27–28 months. Conclusion: this study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioral changes in task performance were observed. PMID:26869921

Protective Effects of Flax Seed (Linum Usitatissimum) Hydroalcoholic Extract on Fetus Brain in Aged and Young Mice.

PubMed

Kamali, Mahsa; Bahmanpour, Soghra

2016-05-01

One of the major problems of the aged women or older than 35 is getting pregnant in the late fertility life. Fertility rates begin to decline gradually at the age of 30, more so at 35, and markedly at 40. Even with fertility treatments such as in vitro fertilization, women have more difficulty in getting pregnant or may deliver abnormal fetus. The purpose of this study was to assess the effects of flax seed hydroalcoholic extract on the fetal brain of aged mice and its comparison with young mice. In this experimental study, 32 aged and 32 young mice were divided into 4 groups. Controls received no special treatment. The experimental mice groups, 3 weeks before mating, were fed with flax seed hydroalcoholic extract by oral gavages. After giving birth, the brains of the fetus were removed. Data analysis was performed by statistical test ANOVA using SPSS version 18 (P<0.05). The mean fetus brain weight of aged mother groups compared to the control group was increased significantly (P<0.05). This study showed that flax seed hydroalcoholic extract could improve fetal brain weights in the aged groups.

Circadian rhythm resynchronization improved isoflurane-induced cognitive dysfunction in aged mice.

PubMed

Song, Jia; Chu, Shuaishuai; Cui, Yin; Qian, Yue; Li, Xiuxiu; Xu, Fangxia; Shao, Xueming; Ma, Zhengliang; Xia, Tianjiao; Gu, Xiaoping

2018-04-13

Postoperative cognitive dysfunction (POCD) is a common clinical phenomenon characterized by cognitive deficits in patients after anesthesia and surgery. Advanced age is a significant independent risk factor for POCD. We previously reported that in young mice, sleep-wake rhythm is involved in the isoflurane-induced memory impairment. In present study, we sought to determine whether advanced age increased the risk of POCD through aggravated and prolonged post-anesthetic circadian disruption in the elderly. We constructed POCD model by submitting the mice to 5-h 1.3% isoflurane anesthesia from Zeitgeber Time (ZT) 14 to ZT19. Under novel object recognition assay (NOR) and Morris water maze (MWM) test, We found 5-h isoflurane anesthesia impaired the cognition of young mice for early 3 days after anesthesia but damaged the aged for at least 1 week. With Mini-Mitter continuously monitoring, a 3.22 ± 0.75 h gross motor activity acrophase delay was manifested in young mice on D1, while in the aged mice, the gross motor activity phase shift lasted for 3 days, consistent with the body temperature rhythm trends of change. Melatonin has been considered as an effective remedy for circadian rhythm shift. In aged mice, melatonin was pretreated intragastrically at the dose of 10 mg/kg daily for 7 consecutive days before anesthesia. We found that melatonin prevented isoflurane-induced cognitive impairments by restoring the locomotor activity and temperature circadian rhythm via clock gene resynchronization. Overall, these results indicated that Long-term isoflurane anesthesia induced more aggravated and prolonged memory deficits and circadian rhythms disruption in aged mice. Melatonin could prevent isoflurane-induced cognitive impairments by circadian rhythm resynchronization. Copyright © 2018. Published by Elsevier Inc.

A Dietary Treatment Improves Cerebral Blood Flow and Brain Connectivity in Aging apoE4 Mice

PubMed Central

Wiesmann, Maximilian; Zerbi, Valerio; Jansen, Diane; Haast, Roy; Lütjohann, Dieter; Broersen, Laus M.; Heerschap, Arend

2016-01-01

APOE ε4 (apoE4) polymorphism is the main genetic determinant of sporadic Alzheimer's disease (AD). A dietary approach (Fortasyn) including docosahexaenoic acid, eicosapentaenoic acid, uridine, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium has been proposed for dietary management of AD. We hypothesize that the diet could inhibit AD-like pathologies in apoE4 mice, specifically cerebrovascular and connectivity impairment. Moreover, we evaluated the diet effect on cerebral blood flow (CBF), functional connectivity (FC), gray/white matter integrity, and postsynaptic density in aging apoE4 mice. At 10–12 months, apoE4 mice did not display prominent pathological differences compared to wild-type (WT) mice. However, 16–18-month-old apoE4 mice revealed reduced CBF and accelerated synaptic loss. The diet increased cortical CBF and amount of synapses and improved white matter integrity and FC in both aging apoE4 and WT mice. We demonstrated that protective mechanisms on vascular and synapse health are enhanced by Fortasyn, independent of apoE genotype. We further showed the efficacy of a multimodal translational approach, including advanced MR neuroimaging, to study dietary intervention on brain structure and function in aging. PMID:27034849

Transcriptional profiling reveals progeroid Ercc1-/Δ mice as a model system for glomerular aging

PubMed Central

2013-01-01

Background Aging-related kidney diseases are a major health concern. Currently, models to study renal aging are lacking. Due to a reduced life-span progeroid models hold the promise to facilitate aging studies and allow examination of tissue-specific changes. Defects in genome maintenance in the Ercc1-/Δ progeroid mouse model result in premature aging and typical age-related pathologies. Here, we compared the glomerular transcriptome of young and aged Ercc1-deficient mice to young and aged WT mice in order to establish a novel model for research of aging-related kidney disease. Results In a principal component analysis, age and genotype emerged as first and second principal components. Hierarchical clustering of all 521 genes differentially regulated between young and old WT and young and old Ercc1-/Δ mice showed cluster formation between young WT and Ercc1-/Δ as well as old WT and Ercc1-/Δ samples. An unexpectedly high number of 77 genes were differentially regulated in both WT and Ercc1-/Δ mice (p < 0.0001). GO term enrichment analysis revealed these genes to be involved in immune and inflammatory response, cell death, and chemotaxis. In a network analysis, these genes were part of insulin signaling, chemokine and cytokine signaling and extracellular matrix pathways. Conclusion Beyond insulin signaling, we find chemokine and cytokine signaling as well as modifiers of extracellular matrix composition to be subject to major changes in the aging glomerulus. At the level of the transcriptome, the pattern of gene activities is similar in the progeroid Ercc1-/Δ mouse model constituting a valuable tool for future studies of aging-associated glomerular pathologies. PMID:23947592

Transcriptional profiling reveals progeroid Ercc1(-/Δ) mice as a model system for glomerular aging.

PubMed

Schermer, Bernhard; Bartels, Valerie; Frommolt, Peter; Habermann, Bianca; Braun, Fabian; Schultze, Joachim L; Roodbergen, Marianne; Hoeijmakers, Jan Hj; Schumacher, Björn; Nürnberg, Peter; Dollé, Martijn Et; Benzing, Thomas; Müller, Roman-Ulrich; Kurschat, Christine E

2013-08-16

Aging-related kidney diseases are a major health concern. Currently, models to study renal aging are lacking. Due to a reduced life-span progeroid models hold the promise to facilitate aging studies and allow examination of tissue-specific changes. Defects in genome maintenance in the Ercc1(-/Δ) progeroid mouse model result in premature aging and typical age-related pathologies. Here, we compared the glomerular transcriptome of young and aged Ercc1-deficient mice to young and aged WT mice in order to establish a novel model for research of aging-related kidney disease. In a principal component analysis, age and genotype emerged as first and second principal components. Hierarchical clustering of all 521 genes differentially regulated between young and old WT and young and old Ercc1(-/Δ) mice showed cluster formation between young WT and Ercc1(-/Δ) as well as old WT and Ercc1(-/Δ) samples. An unexpectedly high number of 77 genes were differentially regulated in both WT and Ercc1(-/Δ) mice (p < 0.0001). GO term enrichment analysis revealed these genes to be involved in immune and inflammatory response, cell death, and chemotaxis. In a network analysis, these genes were part of insulin signaling, chemokine and cytokine signaling and extracellular matrix pathways. Beyond insulin signaling, we find chemokine and cytokine signaling as well as modifiers of extracellular matrix composition to be subject to major changes in the aging glomerulus. At the level of the transcriptome, the pattern of gene activities is similar in the progeroid Ercc1(-/Δ) mouse model constituting a valuable tool for future studies of aging-associated glomerular pathologies.

Relationship between the effect of dietary fat on swimming endurance and energy metabolism in aged mice.

PubMed

Zhang, Guihua; Shirai, Nobuya; Suzuki, Hiramitsu

2011-10-01

The aim of this study was to investigate the effect of different dietary fats on alterations in endurance, energy metabolism, and plasma levels of interleukin-6 (IL-6) and minerals in mice. Male mice (aged 58 weeks) were fed diets containing 6% safflower oil, fish oil, or lard for 12 weeks. Swimming time to exhaustion, energy metabolism, and plasma IL-6 levels were subsequently determined. Mice fed safflower oil exhibited a marked increase in swimming time compared to the baseline level. Mice fed lard exhibited a significant decrease in swimming time, while mice on a fish oil diet exhibited a small decrease in swimming time. The final swimming time of mice fed safflower oil was significantly longer than that of animals fed lard. This improvement in endurance with dietary safflower oil was accompanied by decreased accumulation of lactate and less glycogen depletion during swimming. In the safflower oil group, muscle carnitine palmitoyltransferase activity increased significantly after swimming, while the plasma non-esterified fatty acid concentration decreased significantly. A trend to increased plasma IL-6 levels was observed in sedentary animals on a safflower oil diet compared to those on a lard diet. These results suggest that dietary safflower oil improves the swimming endurance of aged mice to a greater extent than lard, and that this effect appears to involve glycogen sparing through increased fatty acid utilization. Copyright © 2011 S. Karger AG, Basel.

Minimal impact of age and housing temperature on the metabolic phenotype of Acc2-/- mice.

PubMed

Brandon, Amanda E; Stuart, Ella; Leslie, Simon J; Hoehn, Kyle L; James, David E; Kraegen, Edward W; Turner, Nigel; Cooney, Gregory J

2016-03-01

An important regulator of fatty acid oxidation (FAO) is the allosteric inhibition of CPT-1 by malonyl-CoA produced by the enzyme acetyl-CoA carboxylase 2 (ACC2). Initial studies suggested that deletion of Acc2 (Acacb) increased fat oxidation and reduced adipose tissue mass but in an independently generated strain of Acc2 knockout mice we observed increased whole-body and skeletal muscle FAO and a compensatory increase in muscle glycogen stores without changes in glucose tolerance, energy expenditure or fat mass in young mice (12-16 weeks). The aim of the present study was to determine whether there was any effect of age or housing at thermoneutrality (29 °C; which reduces total energy expenditure) on the phenotype of Acc2 knockout mice. At 42-54 weeks of age, male WT and Acc2(-/-) mice had similar body weight, fat mass, muscle triglyceride content and glucose tolerance. Consistent with younger Acc2(-/-) mice, aged Acc2(-/-) mice showed increased whole-body FAO (24 h average respiratory exchange ratio=0.95±0.02 and 0.92±0.02 for WT and Acc2(-/-) mice respectively, P<0.05) and skeletal muscle glycogen content (+60%, P<0.05) without any detectable change in whole-body energy expenditure. Hyperinsulinaemic-euglycaemic clamp studies revealed no difference in insulin action between groups with similar glucose infusion rates and tissue glucose uptake. Housing Acc2(-/-) mice at 29 °C did not alter body composition, glucose tolerance or the effects of fat feeding compared with WT mice. These results confirm that manipulation of Acc2 may alter FAO in mice, but this has little impact on body composition or insulin action. © 2016 Society for Endocrinology.

Effects of Bushen-Yizhi formula on age-related inflammation and oxidative stress in senescence-accelerated mice

PubMed Central

Hou, Xue-Qin; Song, Hou-Pan; Chen, Yun-Bo; Cheng, Shu-Yi; Fang, Shu-Huan; Zhang, Ji-Guo; Wang, Qi

2018-01-01

The present study aimed to investigate the possible effects and underlying molecular mechanism of Bushen-Yizhi formula (BSYZ), a traditional Chinese medicine, on age-related degeneration of brain physiology in senescence-accelerated mouse prone 8 (SAMP8) mice. SAMP8 mice (age, 6 months) were administered BSYZ (1.46, 2.92 and 5.84 g/kg/day) for 30 days. Morris water maze and step-down tests demonstrated that BSYZ significantly improved memory impairments in SAMP8 mice. In addition, BSYZ significantly enhanced the expression levels of peroxisome proliferator-activated receptor-γ and B-cell lymphoma extra-large, and downregulated the expression levels of inflammatory mediators, glial fibrillary acidic protein, cyclooxygenase-2, nuclear factor-κB and interleukin-1β in the brain compared with untreated SAMP8 mice. Furthermore, BSYZ reversed disordered superoxide dismutase activity, malondialdehyde content and glutathione peroxidase activity, and ameliorated apoptosis and histological alterations. The present study indicated that BSYZ may attenuate cognitive impairment in SAMP8 mice, and modulate inflammation, oxidative stress and neuronal apoptosis. These results suggested that BSYZ may have the potential to be further developed into a therapeutic agent for protection against age-related neurodegenerative diseases. PMID:29568888

Depletion of Pax7+ satellite cells does not affect diaphragm adaptations to running in young or aged mice.

PubMed

Murach, Kevin A; Confides, Amy L; Ho, Angel; Jackson, Janna R; Ghazala, Lina S; Peterson, Charlotte A; Dupont-Versteegden, Esther E

2017-10-01

Satellite cell depletion does not affect diaphragm adaptations to voluntary wheel running in young or aged mice. Satellite cell depletion early in life (4 months of age) has minimal effect on diaphragm phenotype by old age (24 months). Prolonged satellite cell depletion in the diaphragm does not result in excessive extracellular matrix accumulation, in contrast to what has been reported in hind limb muscles. Up-regulation of Pax3 mRNA+ cells after satellite cell depletion in young and aged mice suggests that Pax3+ cells may compensate for a loss of Pax7+ satellite cells in the diaphragm. Future investigations should focus on the role of Pax3+ cells in the diaphragm during adaptation to exercise and ageing. Satellite cell contribution to unstressed diaphragm is higher compared to hind limb muscles, which is probably attributable to constant activation of this muscle to drive ventilation. Whether satellite cell depletion negatively impacts diaphragm quantitative and qualitative characteristics under stressed conditions in young and aged mice is unknown. We therefore challenged the diaphragm with prolonged running activity in the presence and absence of Pax7+ satellite cells in young and aged mice using an inducible Pax7 CreER -R26R DTA model. Mice were vehicle (Veh, satellite cell-replete) or tamoxifen (Tam, satellite cell-depleted) treated at 4 months of age and were then allowed to run voluntarily at 6 months (young) and 22 months (aged). Age-matched, cage-dwelling, Veh- and Tam-treated mice without wheel access served as activity controls. Diaphragm muscles were analysed from young (8 months) and aged (24 months) mice. Satellite cell depletion did not alter diaphragm mean fibre cross-sectional area, fibre type distribution or extracellular matrix content in young or aged mice, regardless of running activity. Resting in vivo diaphragm function was also unaffected by satellite cell depletion. Myonuclear density was maintained in young satellite cell

Sex differences in distortion product otoacoustic emissions as a function of age in CBA mice.

PubMed

Guimaraes, Patricia; Zhu, Xiaoxia; Cannon, Trinitia; Kim, SungHee; Frisina, Robert D

2004-06-01

Age-related hearing loss--presbycusis--is the number one communication problem of the aged. A major contributor to presbycusis is the progressive degeneration of cochlear outer hair cells (OHCs). Distortion product otoacoustic emissions (DPOAEs) are effective in vivo, physiological measures of hearing, assessing the health and functioning of the OHCs in mammals. We and others have previously demonstrated that DPOAE amplitudes decline with age in humans and mice. The present study's objective was to measure age-related declines in the OHCs in CBA mice (slow, progressive age-related hearing loss) by comparing DPOAEs and auditory brainstem responses (ABRs) generated from females and males. Young adult (2.1-2.9 months) and middle-aged CBA (14.0-16.4 months) mice were tested, as well as old CBAs (24.3-29.0 months). DPOAE-grams were obtained with L1 = 65 and L2 = 50 dB SPL, f1/f2 = 1.25, using eight points per octave covering a frequency range from 5.6 to 44.8 kHz (geometric mean frequency). ABRs ranged from 3 to 48 kHz. Analyses revealed that DPOAE levels decreased with age for middle-aged and old male CBAs, but for female CBAs, declines did not occur until old age - after menopause. In contrast, ABR amplitudes for female and male young adult and middle-aged CBAs were the same. Female ABR thresholds were lower than males for old CBAs. In conclusion, we discovered that pre-menopausal CBA female mice have healthier OHCs relative to middle-aged males, but much of this relative advantage is lost post-menopause. Understanding sex differences in age-related sensory disorders will be quite helpful for the goals of preventing, slowing or curing sensory problems in old age for both women and men.

Experimental induction of type 2 diabetes in aging-accelerated mice triggered Alzheimer-like pathology and memory deficits.

PubMed

Mehla, Jogender; Chauhan, Balwantsinh C; Chauhan, Neelima B

2014-01-01

Alzheimer's disease (AD) is an age-dependent neurodegenerative disease constituting ~95% of late-onset non-familial/sporadic AD, and only ~5% accounting for early-onset familial AD. Availability of a pertinent model representing sporadic AD is essential for testing candidate therapies. Emerging evidence indicates a causal link between diabetes and AD. People with diabetes are >1.5-fold more likely to develop AD. Senescence-accelerated mouse model (SAMP8) of accelerated aging displays many features occurring early in AD. Given the role played by diabetes in the pre-disposition of AD, and the utility of SAMP8 non-transgenic mouse model of accelerated aging, we examined if high fat diet-induced experimental type 2 diabetes in SAMP8 mice will trigger pathological aging of the brain. Results showed that compared to non-diabetic SAMP8 mice, diabetic SAMP8 mice exhibited increased cerebral amyloid-β, dysregulated tau-phosphorylating glycogen synthase kinase 3β, reduced synaptophysin immunoreactivity, and displayed memory deficits, indicating Alzheimer-like changes. High fat diet-induced type 2 diabetic SAMP8 mice may represent the metabolic model of AD.

Psychological stress exposure to aged mice causes abnormal feeding patterns with changes in the bout number.

PubMed

Yamada, Chihiro; Mogami, Sachiko; Hattori, Tomohisa

2017-11-09

Stress responses are affected by aging. However, studies on stress-related changes in feeding patterns with aging subject are minimal. We investigated feeding patterns induced by two psychological stress models, revealing characteristics of stress-induced feeding patterns as "meal" and "bout" (defined as the minimum feeding behavior parameters) in aged mice. Feeding behaviors of C57BL/6J mice were monitored for 24 h by an automatic monitoring device. Novelty stress reduced the meal amount over the 24 h in both young and aged mice, but as a result of a time course study it was persistent in aged mice. In addition, the decreased bout number was more pronounced in aged mice than in young mice. The 24-h meal and bout parameters did not change in either the young or aged mice following water avoidance stress (WAS). However, the meal amount and bout number increased in aged mice for 0-6 h after WAS exposure but remained unchanged in young mice. Our findings suggest that changes in bout number may lead to abnormal stress-related feeding patterns and may be one tool for evaluating eating abnormality in aged mice.

Oxidative Stress Induced Age Dependent Meibomian Gland Dysfunction in Cu, Zn-Superoxide Dismutase-1 (Sod1) Knockout Mice

PubMed Central

Ibrahim, Osama M. A.; Dogru, Murat; Matsumoto, Yukihiro; Igarashi, Ayako; Kojima, Takashi; Wakamatsu, Tais Hitomi; Inaba, Takaaki; Shimizu, Takahiko; Shimazaki, Jun; Tsubota, Kazuo

2014-01-01

Purpose The purpose of our study was to investigate alterations in the meibomian gland (MG) in Cu, Zn-Superoxide Dismutase-1 knockout (Sod1 −/−) mouse. Methods Tear function tests [Break up time (BUT) and cotton thread] and ocular vital staining test were performed on Sod1 −/− male mice (n = 24) aged 10 and 50 weeks, and age and sex matched wild–type (+/+) mice (n = 25). Tear and serum samples were collected at sacrifice for inflammatory cytokine assays. MG specimens underwent Hematoxylin and Eosin staining, Mallory staining for fibrosis, Oil Red O lipid staining, TUNEL staining, immunohistochemistry stainings for 4HNE, 8-OHdG and CD45. Transmission electron microscopic examination (TEM) was also performed. Results Corneal vital staining scores in the Sod1 −/− mice were significantly higher compared with the wild type mice throughout the follow-up. Tear and serum IL-6 and TNF-α levels also showed significant elevations in the 10 to 50 week Sod1 −/− mice. Oil Red O staining showed an accumulation of large lipid droplets in the Sod1 −/− mice at 50 weeks. Immunohistochemistry revealed both increased TUNEL and oxidative stress marker stainings of the MG acinar epithelium in the Sod1 −/− mice compared to the wild type mice. Immunohistochemistry staining for CD45 showed increasing inflammatory cell infiltrates from 10 to 50 weeks in the Sod1 −/− mice compared to the wild type mice. TEM revealed prominent mitochondrial changes in 50 week Sod1 −/− mice. Conclusions Our results suggest that reactive oxygen species might play a vital role in the pathogensis of meibomian gland dysfunction. The Sod1 −/− mouse appears to be a promising model for the study of reactive oxygen species associated MG alterations. PMID:25036096

Suppression of Oxidative Stress by Resveratrol After Isometric Contractions in Gastrocnemius Muscles of Aged Mice

PubMed Central

Ryan, Michael J.; Jackson, Janna R.; Hao, Yanlei; Williamson, Courtney L.; Dabkowski, Erinne R.; Hollander, John M.

2010-01-01

This study tested the hypothesis that resveratrol supplementation would lower oxidative stress in exercised muscles of aged mice. Young (3 months) and aged (27 months) C57BL/6 mice received a control or a 0.05% trans-resveratrol-supplemented diet for 10 days. After 7 days of dietary intervention, 20 maximal electrically evoked isometric contractions were obtained from the plantar flexors of one limb in anesthetized mice. Exercise was conducted for three consecutive days. Resveratrol supplementation blunted the exercise-induced increase in xanthine oxidase activity in muscles from young (25%) and aged (53%) mice. Resveratrol lowered H2O2 levels in control (13%) and exercised (38%) muscles from aged animals, reduced Nox4 protein in both control and exercised muscles of young (30%) and aged mice (40%), and increased the ratio of reduced glutathione to oxidized glutathione in exercised muscles from young (38%) and aged (135%) mice. Resveratrol prevented the increase in lipid oxidation, increased catalase activity, and increased MnSOD activity in exercised muscles from aged mice. These data show that dietary resveratrol suppresses muscle indicators of oxidative stress in response to isometric contractions in aged mice. PMID:20507922

Sod2 haploinsufficiency does not accelerate aging of telomere dysfunctional mice

PubMed Central

Guachalla, Luis Miguel; Ju, Zhenyu; Koziel, Rafal; von Figura, Guido; Song, Zhangfa; Fusser, Markus; Epe, Bernd; Jansen-Dűrr, Pidder; Rudolph, K. Lenhard

2009-01-01

Telomere shortening represents a causal factor of cellular senescence. At the same time, several lines of evidence indicate a pivotal role of oxidative DNA damage for the aging process in vivo. A causal connection between the two observations was suggested by experiments showing accelerated telomere shorting under conditions of oxidative stress in cultured cells, but has never been studied in vivo. We therefore have analysed whether an increase in mitochondrial derived oxidative stress in response to heterozygous deletion of superoxide dismutase (Sod2+/-) would exacerbate aging phenotypes in telomere dysfunctional (mTerc-/-) mice. Heterozygous deletion of Sod2 resulted in reduced SOD2 protein levels and increased oxidative stress in aging telomere dysfunctional mice, but this did not lead to an increase in basal levels of oxidative nuclear DNA damage, an accumulation of nuclear DNA breaks, or an increased rate of telomere shortening in the mice. Moreover, heterozygous deletion of Sod2 did not accelerate the depletion of stem cells and the impairment in organ maintenance in aging mTerc-/- mice. In agreement with these observations, Sod2 haploinsufficiency did not lead to a further reduction in lifespan of mTerc-/- mice. Together, these results indicate that a decrease in SOD2-dependent antioxidant defence does not exacerbate aging in the context of telomere dysfunction. PMID:20195488

Aging-related changes in respiratory system mechanics and morphometry in mice.

PubMed

Elliott, Jonathan E; Mantilla, Carlos B; Pabelick, Christina M; Roden, Anja C; Sieck, Gary C

2016-07-01

Previous work investigating respiratory system mechanics in mice has reported an aging-related increase in compliance and mean linear intercept (Lm). However, these changes were assessed using only a young (2-mo-old) and old (20- and 26-mo-old) group yet were interpreted to reflect a linear evolution across the life span. Therefore, to investigate respiratory system mechanics and lung morphometry across a more complete spectrum of ages, we utilized 2 (100% survival, n = 6)-, 6 (100% survival, n = 12)-, 18 (90% survival, n = 12)-, 24 (75% survival, n = 12)-, and 30 (25% survival, n = 12)-mo-old C57BL/6 mice. We found a nonlinear aging-related decrease in respiratory system resistance and increase in dynamic compliance and hysteresis between 2- and 24-mo-old mice. However, in 30-mo-old mice, respiratory system resistance increased, and dynamic compliance and hysteresis decreased relative to 24-mo-old mice. Respiratory system impedance spectra were measured between 1-20.5 Hz at positive end-expiratory pressures (PEEP) of 1, 3, 5, and 7 cmH2O. Respiratory system resistance and reactance at each level of PEEP were increased and decreased, respectively, only in 2-mo-old animals. No differences in the respiratory system impedance spectra were observed in 6-, 18-, 24-, and 30-mo-old mice. Additionally, lungs were fixed following tracheal instillation of 4% paraformaldehyde at 25 cmH2O and processed for Lm and airway collagen deposition. There was an aging-related increase in Lm consistent with emphysematous-like changes and no evidence of increased airway collagen deposition. Accordingly, we demonstrate nonlinear aging-related changes in lung mechanics and morphometry in C57BL/6 mice. Copyright © 2016 the American Physiological Society.

Aged mice display an altered pulmonary host response to Francisella tularensis live vaccine strain (LVS) infections

PubMed Central

CA, Mares; SS, Ojeda; Q, Li; EG, Morris; JJ, Coalson; JM, Teale

2012-01-01

Aging is a complex phenomenon that has been shown to affect many organ systems including the innate and adaptive immune systems. The current study was designed to examine the potential effect of immunosenescence on the pulmonary immune response using a Francisella tularensis live vaccine strain (LVS) inhalation infection model. F. tularensis is a gram-negative intracellular pathogen that can cause a severe pneumonia.In this study both young (8-12 week old) and aged (20-24 month old) mice were infected intranasally with LVS. Lung tissues from young and aged mice were used to assess pathology, recruitment of immune cell types and cytokine expression levels at various times post infection. Bacterial burdens were also assessed. Interestingly, the lungs of aged animals harbored fewer organisms at early time points of infection (day 1, day 3) compared with their younger counterparts. In addition, only aged animals displayed small perivascular aggregates at these early time points that appeared mostly mononuclear in nature. However, the kinetics of infiltrating polymorphonuclear neutrophils (PMNs) and increased cytokine levels measured in the bronchial alveolar lavage fluid (BALF) were delayed in infected aged animals relative to young infected animals with neutrophils appearing at day 5 post infection (PI) in the aged animals as opposed to day 3 PI in the young infected animals. Also evident were alterations in the ratios of mononuclear to PMNs at distinct post infection times. The above evidence indicates that aged mice elicit an altered immune response in the lung to respiratory Francisella tularensis LVS infections compared to their younger counterparts. PMID:19825409

Sex differences in neurochemical markers that correlate with behavior in aging mice.

PubMed

Frick, K M; Burlingame, L A; Delaney, S S; Berger-Sweeney, J

2002-01-01

Sex differences in neurochemical markers that correlate with behavior in aging mice NEUROBIOL AGING. We examined whether the enzymatic activities of choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD) were altered similarly with age in male and female mice, and whether these changes were correlated with age-related alterations in memory and anxiety. ChAT and GAD activities were measured in neocortex, hippocampus, and striatum of behaviorally characterized male and female C57BL/6 mice (5, 17, and 25 months). Generally, ChAT activity was increased, and GAD activity decreased, with age. However, disparate changes were revealed between the sexes; activities of both enzymes were decreased in 17-month males, whereas alterations in females were not observed until 25-months. Furthermore, enzyme-behavior correlations differed between the sexes; in males, ChAT activity was related to one behavioral task, whereas in females, activities of both enzymes were correlated with multiple tasks. Significant enzyme-behavior correlations were most evident at 17 months of age, likely the result of behavioral and enzymatic sex differences at this age. These data represent the first comprehensive report illustrating differential alterations of ChAT and GAD activities in aging male and female mice.

Cuprizone-induced demyelination in mice: age-related vulnerability and exploratory behavior deficit.

PubMed

Wang, Hongkai; Li, Chengren; Wang, Hanzhi; Mei, Feng; Liu, Zhi; Shen, Hai-Ying; Xiao, Lan

2013-04-01

Schizophrenia is a mental disease that mainly affects young individuals (15 to 35 years old) but its etiology remains largely undefined. Recently, accumulating evidence indicated that demyelination and/or dysfunction of oligodendrocytes is an important feature of its pathogenesis. We hypothesized that the vulnerability of young individuals to demyelination may contribute to the onset of schizophrenia. In the present study, three different age cohorts of mice, i.e. juvenile (3 weeks), young-adult (6 weeks) and middle-aged (8 months), were subjected to a 6-week diet containing 0.2% cuprizone (CPZ) to create an animal model of acute demyelination. Then, age-related vulnerability to CPZ-induced demyelination, behavioral outcomes, and myelination-related molecular biological changes were assessed. We demonstrated: (1) CPZ treatment led to more severe demyelination in juvenile and young-adult mice than in middle-aged mice in the corpus callosum, a region closely associated with the pathophysiology of schizophrenia; (2) the higher levels of demyelination in juvenile and young-adult mice were correlated with a greater reduction of myelin basic protein, more loss of CC-1-positive mature oligodendrocytes, and higher levels of astrocyte activation; and (3) CPZ treatment resulted in a more prominent exploratory behavior deficit in juvenile and young-adult mice than in middle-aged mice. Together, our data demonstrate an age-related vulnerability to demyelination with a concurrent behavioral deficit, providing supporting evidence for better understanding the susceptibility of the young to the onset of schizophrenia.

Age Dependence of Immunity Induced by a Candidate Universal Influenza Vaccine in Mice

PubMed Central

García, Mayra; Misplon, Julia A.; Price, Graeme E.; Lo, Chia-Yun; Epstein, Suzanne L.

2016-01-01

Influenza has a major impact on the elderly due to increased susceptibility to infection with age and poor response to current vaccines. We have studied universal influenza vaccine candidates based on influenza A nucleoprotein and matrix 2 (A/NP+M2). Long-lasting protection against influenza virus strains of divergent subtypes is induced, especially with mucosal immunization. Here, we tested universal vaccination in BALB/c mice of different ages. Vaccination used intramuscular DNA priming to A/NP+M2 followed by intranasal (i.n.) boosting with recombinant adenoviruses (rAd) expressing the same antigens, or only A/NP+M2-rAd given i.n. Antigen-specific systemic antibody responses were induced in young, middle-aged, and elderly mice (2, 11–17, and 20 months old, respectively), but decreased with age. Antibody responses in bronchoalveolar lavage (BAL) were detected only in young mice. Antigen-specific T cell responses were seen in young and middle-aged but not elderly mice. A/NP+M2 vaccination by the two regimens above protected against stringent challenge in young and middle-aged mice, but not in elderly mice. However, mice vaccinated with A/NP-rAd or A/M2-rAd during their youth were partially protected against challenge 16 months later when they were elderly. In addition, a regimen of two doses of A/NP+M2-rAd given i.n. one month apart beginning in old age protected elderly mice against stringent challenge. This study highlights the potential benefit of cross-protective vaccines through middle age, and suggests that their performance might be enhanced in elderly individuals who had been exposed to influenza antigens early in life, as most humans have been, or by a two-dose rAd regimen given later in life. PMID:27055234

Age Dependence of Immunity Induced by a Candidate Universal Influenza Vaccine in Mice.

PubMed

García, Mayra; Misplon, Julia A; Price, Graeme E; Lo, Chia-Yun; Epstein, Suzanne L

2016-01-01

Influenza has a major impact on the elderly due to increased susceptibility to infection with age and poor response to current vaccines. We have studied universal influenza vaccine candidates based on influenza A nucleoprotein and matrix 2 (A/NP+M2). Long-lasting protection against influenza virus strains of divergent subtypes is induced, especially with mucosal immunization. Here, we tested universal vaccination in BALB/c mice of different ages. Vaccination used intramuscular DNA priming to A/NP+M2 followed by intranasal (i.n.) boosting with recombinant adenoviruses (rAd) expressing the same antigens, or only A/NP+M2-rAd given i.n. Antigen-specific systemic antibody responses were induced in young, middle-aged, and elderly mice (2, 11-17, and 20 months old, respectively), but decreased with age. Antibody responses in bronchoalveolar lavage (BAL) were detected only in young mice. Antigen-specific T cell responses were seen in young and middle-aged but not elderly mice. A/NP+M2 vaccination by the two regimens above protected against stringent challenge in young and middle-aged mice, but not in elderly mice. However, mice vaccinated with A/NP-rAd or A/M2-rAd during their youth were partially protected against challenge 16 months later when they were elderly. In addition, a regimen of two doses of A/NP+M2-rAd given i.n. one month apart beginning in old age protected elderly mice against stringent challenge. This study highlights the potential benefit of cross-protective vaccines through middle age, and suggests that their performance might be enhanced in elderly individuals who had been exposed to influenza antigens early in life, as most humans have been, or by a two-dose rAd regimen given later in life.

Intake of Wild Blueberry Powder Improves Episodic-Like and Working Memory during Normal Aging in Mice.

PubMed

Beracochea, Daniel; Krazem, Ali; Henkouss, Nadia; Haccard, Guillaume; Roller, Marc; Fromentin, Emilie

2016-08-01

The number of Americans older than 65 years old is projected to more than double in the next 40 years. Cognitive changes associated to aging can affect an adult's day-to-day functioning. Among these cognitive changes, reasoning, episodic memory, working memory, and processing speed decline gradually over time. Early memory changes include a decline in both working and episodic memory. The aim of the present study was to determine whether chronic (up to 75 days) daily administration of wild blueberry extract or a wild blueberry full spectrum powder would help prevent memory failure associated with aging in tasks involving various forms of memory. Both blueberry ingredients were used in a study comparing young mice (6 months old) to aged mice (18 months old). At this age, mice exhibit memory decline due to aging, which is exacerbated first by a loss in working and contextual (episodic-like) memory. Contextual memory (episodic-like memory) was evaluated using the contextual serial discrimination test. Working and spatial memory were evaluated using the Morris-Water maze test and the sequential alternation test. Statistical analysis was performed using an ANOVA with the Bonferroni post-hoc test. Supplementation with wild blueberry full spectrum powder and wild blueberry extract resulted in significant improvement of contextual memory, while untreated aged mice experienced a decline in such memory. Only the wild blueberry full spectrum powder significantly contributed to an improvement of spatial and working memory versus untreated aged mice. These improvements of cognitive performance may be related to brain oxidative status, acetylcholinesterase activity, neuroprotection, or attenuation of immunoreactivity. Georg Thieme Verlag KG Stuttgart · New York.

Accelerated protein damage in brains of PIMT+/- mice; a possible model for the variability of cognitive decline in human aging.

PubMed

Qin, Zhenxia; Dimitrijevic, Aleksandra; Aswad, Dana W

2015-02-01

Isoaspartate formation is a common type of protein damage normally kept in check by the repair enzyme protein-L-isoaspartyl methyltransferase (PIMT). Mice with a knockout of the gene (Pcmt1) for this enzyme (KO, -/-) exhibit a pronounced neuropathology with fatal epileptic seizures at 30-60 days. Heterozygous (HZ, +/-) mice have 50% of the PIMT activity found in wild-type (WT, +/+) mice, but appear normal. To see if HZ mice exhibit accelerated aging at the molecular level, we compared brain extracts from HZ and WT mice at 8 months and 2 years with regard to PIMT activity, isoaspartate levels, and activity of an endogenous PIMT substrate, creatine kinase B. PIMT activity declined modestly with age in both genotypes. Isoaspartate was significantly higher in HZ than WT mice at 8 months and more so at 2 years, rising 5× faster in HZ males and 3× faster in females. Creatine kinase activity decreased with age and was always lower in the HZ mice. These findings suggest the individual variation of human PIMT levels may significantly influence the course of age-related central nervous system dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparative analysis of the intestinal flora in type 2 diabetes and nondiabetic mice

PubMed Central

Horie, Masanori; Miura, Takamasa; Hirakata, Satomi; Hosoyama, Akira; Sugino, Sakiko; Umeno, Aya; Murotomi, Kazutoshi; Yoshida, Yasukazu; Koike, Taisuke

2017-01-01

A relationship between type 2 diabetes mellitus (T2DM) and intestinal flora has been suggested since development of analysis technology for intestinal flora. An animal model of T2DM is important for investigation of T2DM. Although there are some animal models of T2DM, a comparison of the intestinal flora of healthy animals with that of T2DM animals has not yet been reported. The intestinal flora of Tsumura Suzuki Obese Diabetes (TSOD) mice was compared with that of Tsumura, Suzuki, Non Obesity (TSNO) mice in the present study. The TSOD mice showed typical type 2 diabetes symptoms, which were high-fat diet-independent. The TSOD and the TSNO mouse models were derived from the same strain, ddY. In this study, we compared the intestinal flora of TSOD mice with that if TSNO mice at 5 and 12 weeks of age. We determined that that the number of operational taxonomic units (OTUs) was significantly higher in the cecum of TSOD mice than in that of TSNO mice. The intestinal flora of the cecum and that of the feces were similar between the TSNO and the TSOD strains. The dominant bacteria in the cecum and feces were of the phyla Firmicutes and Bacteroidetes. However, the content of some bacterial species varied between the two strains. The percentage of Lactobacillus spp. within the general intestinal flora was higher in TSOD mice than in TSNO mice. In contrast, the percentages of order Bacteroidales and family Lachnospiraceae were higher in TSNO mice than in TSOD mice. Some species were observed only in TSOD mice, such as genera Turicibacter and SMB53 (family Clostridiaceae), the percentage of which were 3.8% and 2.0%, respectively. Although further analysis of the metabolism of the individual bacteria in the intestinal flora is essential, genera Turicibacter and SMB53 may be important for the abnormal metabolism of type 2 diabetes. PMID:28701620

Comparative analysis of the intestinal flora in type 2 diabetes and nondiabetic mice.

PubMed

Horie, Masanori; Miura, Takamasa; Hirakata, Satomi; Hosoyama, Akira; Sugino, Sakiko; Umeno, Aya; Murotomi, Kazutoshi; Yoshida, Yasukazu; Koike, Taisuke

2017-10-30

A relationship between type 2 diabetes mellitus (T2DM) and intestinal flora has been suggested since development of analysis technology for intestinal flora. An animal model of T2DM is important for investigation of T2DM. Although there are some animal models of T2DM, a comparison of the intestinal flora of healthy animals with that of T2DM animals has not yet been reported. The intestinal flora of Tsumura Suzuki Obese Diabetes (TSOD) mice was compared with that of Tsumura, Suzuki, Non Obesity (TSNO) mice in the present study. The TSOD mice showed typical type 2 diabetes symptoms, which were high-fat diet-independent. The TSOD and the TSNO mouse models were derived from the same strain, ddY. In this study, we compared the intestinal flora of TSOD mice with that if TSNO mice at 5 and 12 weeks of age. We determined that that the number of operational taxonomic units (OTUs) was significantly higher in the cecum of TSOD mice than in that of TSNO mice. The intestinal flora of the cecum and that of the feces were similar between the TSNO and the TSOD strains. The dominant bacteria in the cecum and feces were of the phyla Firmicutes and Bacteroidetes. However, the content of some bacterial species varied between the two strains. The percentage of Lactobacillus spp. within the general intestinal flora was higher in TSOD mice than in TSNO mice. In contrast, the percentages of order Bacteroidales and family Lachnospiraceae were higher in TSNO mice than in TSOD mice. Some species were observed only in TSOD mice, such as genera Turicibacter and SMB53 (family Clostridiaceae), the percentage of which were 3.8% and 2.0%, respectively. Although further analysis of the metabolism of the individual bacteria in the intestinal flora is essential, genera Turicibacter and SMB53 may be important for the abnormal metabolism of type 2 diabetes.

Altered left ventricular performance in aging physically active mice with an ankle sprain injury.

PubMed

Turner, Michael J; Guderian, Sophie; Wikstrom, Erik A; Huot, Joshua R; Peck, Bailey D; Arthur, Susan T; Marino, Joseph S; Hubbard-Turner, Tricia

2016-02-01

We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p < 0.0001). Beginning at 6 months of age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p < 0.0001) beginning at 9 months of age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p < 0.0001), with higher ratios for the SHAM mice and lower ratios for the ATFL/CFL and SHAMSED mice in response to physical activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p < 0.0001). Regular physical activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan.

Transgenic mice overexpressing glia maturation factor-β, an oxidative stress inducible gene, show premature aging due to Zmpste24 down-regulation.

PubMed

Imai, Rika; Asai, Kanae; Hanai, Jun-ichi; Takenaka, Masaru

2015-07-01

Glia Maturation Factor-β (GMF), a brain specific protein, is induced by proteinuria in renal tubules. Ectopic GMF overexpression causes apoptosisin vitro via cellular vulnerability to oxidative stress. In order to examine the roles of GMF in non-brain tissue, we constructed transgenic mice overexpressing GMF (GMF-TG). The GMF-TG mice exhibited appearance phenotypes associated with premature aging. The GMF-TG mice also demonstrated short lifespans and reduced hair regrowth, suggesting an accelerated aging process. The production of an abnormal lamin A, a nuclear envelope protein, plays a causal role in both normal aging and accelerated aging diseases, known as laminopathies. Importantly, we identified the abnormal lamin A (prelamin A), accompanied by a down-regulation of a lamin A processing enzyme (Zmpste24) in the kidney of the GMF-TG mice. The GMF-TG mice showed accelerated aging in the kidney, compared with wild-type mice, showing increased TGF-β1, CTGF gene and serum creatinine. The gene expression of p21/waf1 was increased at an earlier stage of life, at 10 weeks, which was in turn down-regulated at a later stage, at 60 weeks. In conclusion, we propose that GMF-TG mice might be a novel mouse model of accelerated aging, due to the abnormal lamin A.

Age-dependent changes in nitric oxide synthase activity and protein expression in striata of mice transgenic for the Huntington's disease mutation.

PubMed

Pérez-Severiano, Francisca; Escalante, Bruno; Vergara, Paula; Ríos, Camilo; Segovia, José

2002-09-27

Huntington's disease (HD) is an autosomal hereditary neurodegenerative disorder caused by an abnormal expansion of the CAG repeats that code for a polyglutamine tract in a novel protein called huntingtin (htt). Both patients and experimental animals exhibit oxidative damage in specific areas of the brain, particularly the striatum. Nitric oxide (NO) is involved in many different physiological processes, and under pathological conditions it may promote oxidative damage through the formation of the highly reactive metabolite peroxynitrite; however, it may also play a role protecting cells from oxidative damage. We previously showed a correlation between the progression of the neurological phenotype and striatal oxidative damage in a line of transgenic mice, R6/1, which expresses a human mutated htt exon 1 with 116 CAG repeats. The purpose of the present work was to explore the participation of NO in the progressive oxidative damage that occurs in the striata of R6/1 mice. We analyzed the role of NO by measuring the activity of nitric oxide synthase (NOS) in the striata of transgenic and control mice at different ages. There was no difference in NOS activity between transgenic and wild-type mice at 11 weeks of age. In contrast, 19-week-old transgenic mice showed a significant increase in NOS activity, compared with same age controls. By 35 weeks of age, there was a decrease in NOS activity in transgenic mice when compared with wild-type controls. NOS protein expression was also determined in 11-, 19- and 35-week-old transgenic mice and wild-type littermates. Our results show increased neuronal NOS expression in 19-week-old transgenic mice, followed by a decreased level in 35-week-old mice, compared with controls, a phenomenon that parallels the changes in NOS enzyme activity. The present results suggest that NO is involved in the process leading to striatal oxidative damage and that it is associated with the onset of the progressive neurological phenotype in mice

Lifelong obesity in a polygenic mouse model prevents age- and diet-induced glucose intolerance- obesity is no road to late-onset diabetes in mice.

PubMed

Renne, Ulla; Langhammer, Martina; Brenmoehl, Julia; Walz, Christina; Zeissler, Anja; Tuchscherer, Armin; Piechotta, Marion; Wiesner, Rudolf J; Bielohuby, Maximilian; Hoeflich, Andreas

2013-01-01

Visceral obesity holds a central position in the concept of the metabolic syndrome characterized by glucose intolerance in humans. However, until now it is unclear if obesity by itself is responsible for the development of glucose intolerance. We have used a novel polygenic mouse model characterized by genetically fixed obesity (DU6) and addressed age- and high fat diet-dependent glucose tolerance. Phenotype selection over 146 generations increased body weight by about 2.7-fold in male 12-week DU6 mice (P<0.0001) if compared to unselected controls (Fzt:DU). Absolute epididymal fat mass was particularly responsive to weight selection and increased by more than 5-fold (P<0.0001) in male DU6 mice. At an age of 6 weeks DU6 mice consumed about twice as much food if compared to unselected controls (P<0.001). Absolute food consumption was higher at all time points measured in DU6 mice than in Fzt:DU mice. Between 6 and 12 weeks of age, absolute food intake was reduced by 15% in DU6 mice (P<0.001) but not in Fzt:DU mice. In both mouse lines feeding of the high fat diet elevated body mass if compared to the control diet (P<0.05). In contrast to controls, DU6 mice did not display high fat diet-induced increases of epididymal and renal fat. Control mice progressively developed glucose intolerance with advancing age and even more in response to the high fat diet. In contrast, obese DU6 mice did neither develop a glucose intolerant phenotype with progressive age nor when challenged with a high fat diet. Our results from a polygenic mouse model demonstrate that genetically pre-determined and life-long obesity is no precondition of glucose intolerance later in life.

Mitochondria-targeted antioxidant (MitoQ) ameliorates age-related arterial endothelial dysfunction in mice.

PubMed

Gioscia-Ryan, Rachel A; LaRocca, Thomas J; Sindler, Amy L; Zigler, Melanie C; Murphy, Michael P; Seals, Douglas R

2014-06-15

Age-related arterial endothelial dysfunction, a key antecedent of the development of cardiovascular disease (CVD), is largely caused by a reduction in nitric oxide (NO) bioavailability as a consequence of oxidative stress. Mitochondria are a major source and target of vascular oxidative stress when dysregulated. Mitochondrial dysregulation is associated with primary ageing, but its role in age-related endothelial dysfunction is unknown. Our aim was to determine the efficacy of a mitochondria-targeted antioxidant, MitoQ, in ameliorating vascular endothelial dysfunction in old mice. Ex vivo carotid artery endothelium-dependent dilation (EDD) to increasing doses of acetylcholine was impaired by ∼30% in old (∼27 months) compared with young (∼8 months) mice as a result of reduced NO bioavailability (P < 0.05). Acute (ex vivo) and chronic (4 weeks in drinking water) administration of MitoQ completely restored EDD in older mice by improving NO bioavailability. There were no effects of age or MitoQ on endothelium-independent dilation to sodium nitroprusside. The improvements in endothelial function with MitoQ supplementation were associated with the normalization of age-related increases in total and mitochondria-derived arterial superoxide production and oxidative stress (nitrotyrosine abundance), as well as with increases in markers of vascular mitochondrial health, including antioxidant status. MitoQ also reversed the age-related increase in endothelial susceptibility to acute mitochondrial damage (rotenone-induced impairment in EDD). Our results suggest that mitochondria-derived oxidative stress is an important mechanism underlying the development of endothelial dysfunction in primary ageing. Mitochondria-targeted antioxidants such as MitoQ represent a promising novel strategy for the preservation of vascular endothelial function with advancing age and the prevention of age-related CVD. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological

Mitochondria-targeted antioxidant (MitoQ) ameliorates age-related arterial endothelial dysfunction in mice

PubMed Central

Gioscia-Ryan, Rachel A; LaRocca, Thomas J; Sindler, Amy L; Zigler, Melanie C; Murphy, Michael P; Seals, Douglas R

2014-01-01

Age-related arterial endothelial dysfunction, a key antecedent of the development of cardiovascular disease (CVD), is largely caused by a reduction in nitric oxide (NO) bioavailability as a consequence of oxidative stress. Mitochondria are a major source and target of vascular oxidative stress when dysregulated. Mitochondrial dysregulation is associated with primary ageing, but its role in age-related endothelial dysfunction is unknown. Our aim was to determine the efficacy of a mitochondria-targeted antioxidant, MitoQ, in ameliorating vascular endothelial dysfunction in old mice. Ex vivo carotid artery endothelium-dependent dilation (EDD) to increasing doses of acetylcholine was impaired by ∼30% in old (∼27 months) compared with young (∼8 months) mice as a result of reduced NO bioavailability (P < 0.05). Acute (ex vivo) and chronic (4 weeks in drinking water) administration of MitoQ completely restored EDD in older mice by improving NO bioavailability. There were no effects of age or MitoQ on endothelium-independent dilation to sodium nitroprusside. The improvements in endothelial function with MitoQ supplementation were associated with the normalization of age-related increases in total and mitochondria-derived arterial superoxide production and oxidative stress (nitrotyrosine abundance), as well as with increases in markers of vascular mitochondrial health, including antioxidant status. MitoQ also reversed the age-related increase in endothelial susceptibility to acute mitochondrial damage (rotenone-induced impairment in EDD). Our results suggest that mitochondria-derived oxidative stress is an important mechanism underlying the development of endothelial dysfunction in primary ageing. Mitochondria-targeted antioxidants such as MitoQ represent a promising novel strategy for the preservation of vascular endothelial function with advancing age and the prevention of age-related CVD. PMID:24665093

Fasting and Fast Food Diet Play an Opposite Role in Mice Brain Aging.

PubMed

Castrogiovanni, Paola; Li Volti, Giovanni; Sanfilippo, Cristina; Tibullo, Daniele; Galvano, Fabio; Vecchio, Michele; Avola, Roberto; Barbagallo, Ignazio; Malaguarnera, Lucia; Castorina, Sergio; Musumeci, Giuseppe; Imbesi, Rosa; Di Rosa, Michelino

2018-01-20

Fasting may be exploited as a possible strategy for prevention and treatment of several diseases such as diabetes, obesity, and aging. On the other hand, high-fat diet (HFD) represents a risk factor for several diseases and increased mortality. The aim of the present study was to evaluate the impact of fasting on mouse brain aging transcriptome and how HFD regulates such pathways. We used the NCBI Gene Expression Omnibus (GEO) database, in order to identify suitable microarray datasets comparing mouse brain transcriptome under fasting or HFD vs aged mouse brain transcriptome. Three microarray datasets were selected for this study, GSE24504, GSE6285, and GSE8150, and the principal molecular mechanisms involved in this process were evaluated. This analysis showed that, regardless of fasting duration, mouse brain significantly expressed 21 and 30 upregulated and downregulated genes, respectively. The involved biological processes were related to cell cycle arrest, cell death inhibition, and regulation of cellular metabolism. Comparing mouse brain transcriptome under fasting and aged conditions, we found out that the number of genes in common increased with the duration of fasting (222 genes), peaking at 72 h. In addition, mouse brain transcriptome under HFD resembles for the 30% the one of the aged mice. Furthermore, several molecular processes were found to be shared between HFD and aging. In conclusion, we suggest that fasting and HFD play an opposite role in brain transcriptome of aged mice. Therefore, an intermittent diet could represent a possible clinical strategy to counteract aging, loss of memory, and neuroinflammation. Furthermore, low-fat diet leads to the inactivation of brain degenerative processes triggered by aging.

Coffee treatment prevents the progression of sarcopenia in aged mice in vivo and in vitro.

PubMed

Guo, Yinting; Niu, Kaijun; Okazaki, Tatsuma; Wu, Hongmei; Yoshikawa, Takeo; Ohrui, Takashi; Furukawa, Katsutoshi; Ichinose, Masakazu; Yanai, Kazuhiko; Arai, Hiroyuki; Huang, Guowei; Nagatomi, Ryoichi

2014-02-01

Sarcopenia is characterized by the age-related loss of muscle mass and strength, which results in higher mortality in aged people. One of the mechanisms of the sarcopenia is the loss in the function and number of muscle satellite cells. Chronic low-grade inflammation plays a central role in the pathogenesis of age-related sarcopenia. Accumulating evidence suggests that coffee, one of the most widely consumed beverages in the world, has potential pharmacological benefits such as anti-inflammatory and anti-oxidant effects. Since these effects may improve sarcopenia and the functions of satellite cells, we examined the effects of coffee on the skeletal muscles in an animal model using aged mice. In vivo, coffee treatment attenuated the decrease in the muscle weight and grip strength, increased the regenerating capacity of injured muscles, and decreased the serum pro-inflammatory mediator levels compared to controls. In vitro, using satellite cells isolated from aged mice, coffee treatment increased the cell proliferation rate, augmented the cell cycle, and increased the activation level of Akt intra-cellular signaling pathway compared to controls. These findings suggest that the coffee treatment had a beneficial effect on age-related sarcopenia. Copyright © 2013 Elsevier Inc. All rights reserved.

Epigenetic aging signatures in mice livers are slowed by dwarfism, calorie restriction and rapamycin treatment.

PubMed

Wang, Tina; Tsui, Brian; Kreisberg, Jason F; Robertson, Neil A; Gross, Andrew M; Yu, Michael Ku; Carter, Hannah; Brown-Borg, Holly M; Adams, Peter D; Ideker, Trey

2017-03-28

Global but predictable changes impact the DNA methylome as we age, acting as a type of molecular clock. This clock can be hastened by conditions that decrease lifespan, raising the question of whether it can also be slowed, for example, by conditions that increase lifespan. Mice are particularly appealing organisms for studies of mammalian aging; however, epigenetic clocks have thus far been formulated only in humans. We first examined whether mice and humans experience similar patterns of change in the methylome with age. We found moderate conservation of CpG sites for which methylation is altered with age, with both species showing an increase in methylome disorder during aging. Based on this analysis, we formulated an epigenetic-aging model in mice using the liver methylomes of 107 mice from 0.2 to 26.0 months old. To examine whether epigenetic aging signatures are slowed by longevity-promoting interventions, we analyzed 28 additional methylomes from mice subjected to lifespan-extending conditions, including Prop1 df/df dwarfism, calorie restriction or dietary rapamycin. We found that mice treated with these lifespan-extending interventions were significantly younger in epigenetic age than their untreated, wild-type age-matched controls. This study shows that lifespan-extending conditions can slow molecular changes associated with an epigenetic clock in mice livers.

AGED DOMINANT NEGATIVE p38α MAPK MICE ARE RESISTANT TO AGE-DEPENDENT DECLINE IN ADULT-NEUROGENESIS AND CONTEXT DISCRIMINATION FEAR CONDITIONING

PubMed Central

Cortez, IbDanelo; Bulavin, Dmitry V.; Wu, Ping; McGrath, Erica L; Cunningham, Kathryn A; Wakamiya, Maki; Papaconstantinou, John; Dineley, Kelly T

2018-01-01

A major aspect of mammalian aging is the decline in functional competence of many self-renewing cell types, including adult-born neuronal precursors. Since age-related senescence of self-renewal occurs simultaneously with chronic up-regulation of the p38MAPKalpha (p38α) signaling pathway, we used the dominant negative mouse model for attenuated p38α activity (DN-p38αAF/+ ) in which Thr180 and Tyr182 are mutated (T→A/Y→F) to prevent phosphorylation activation (DN-p38αAF/+) and kinase activity. As a result, aged DN-p38αAF/+ mice are resistant to age-dependent decline in proliferation and regeneration of several peripheral tissue progenitors when compared to wild-type littermates. Aging is the major risk factor for non-inherited forms of Alzheimer’s disease (AD); environmental and genetic risk factors that accelerate the senescence phenotype are thought to contribute to an individual’s relative risk. In the present study, we evaluated aged DN-p38αAF/+ and wildtype littermates in a series of behavioral paradigms to test if p38α mutant mice exhibit altered baseline abnormalities in neurological reflexes, locomotion, anxiety-like behavior, and age-dependent cognitive decline. While aged DN-p38αAF/+ and wildtype littermates appear equal in all tested baseline neurological and behavioral parameters, DN-p38αAF/+ exhibit superior context discrimination fear conditioning. Context discrimination is a cognitive task that is supported by proliferation and differentiation of adult-born neurons in the dentate gyrus of the hippocampus. Consistent with enhanced context discrimination in aged DN-p38αAF/+, we discovered enhanced production of adult-born neurons in the dentate gyrus of DN-p38αAF/+ mice compared to wildtype littermates. Our findings support the notion that p38α inhibition has therapeutic utility in aging diseases that affect cognition, such as AD. PMID:27765672

Aged dominant negative p38α MAPK mice are resistant to age-dependent decline in adult-neurogenesis and context discrimination fear conditioning.

PubMed

Cortez, IbDanelo; Bulavin, Dmitry V; Wu, Ping; McGrath, Erica L; Cunningham, Kathryn A; Wakamiya, Maki; Papaconstantinou, John; Dineley, Kelly T

2017-03-30

A major aspect of mammalian aging is the decline in functional competence of many self-renewing cell types, including adult-born neuronal precursors. Since age-related senescence of self-renewal occurs simultaneously with chronic up-regulation of the p38MAPKalpha (p38α) signaling pathway, we used the dominant negative mouse model for attenuated p38α activity (DN-p38α AF/+ ) in which Thr180 and Tyr182 are mutated (T→A/Y→F) to prevent phosphorylation activation (DN-p38α AF/+ ) and kinase activity. As a result, aged DN-p38α AF/+ mice are resistant to age-dependent decline in proliferation and regeneration of several peripheral tissue progenitors when compared to wild-type littermates. Aging is the major risk factor for non-inherited forms of Alzheimer's disease (AD); environmental and genetic risk factors that accelerate the senescence phenotype are thought to contribute to an individual's relative risk. In the present study, we evaluated aged DN-p38α AF/+ and wildtype littermates in a series of behavioral paradigms to test if p38α mutant mice exhibit altered baseline abnormalities in neurological reflexes, locomotion, anxiety-like behavior, and age-dependent cognitive decline. While aged DN-p38α AF/+ and wildtype littermates appear equal in all tested baseline neurological and behavioral parameters, DN-p38α AF/+ exhibit superior context discrimination fear conditioning. Context discrimination is a cognitive task that is supported by proliferation and differentiation of adult-born neurons in the dentate gyrus of the hippocampus. Consistent with enhanced context discrimination in aged DN-p38α AF/+ , we discovered enhanced production of adult-born neurons in the dentate gyrus of DN-p38α AF/+ mice compared to wildtype littermates. Our findings support the notion that p38α inhibition has therapeutic utility in aging diseases that affect cognition, such as AD. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Sleep Deprivation and Aging on Long-Term and Remote Memory in Mice

ERIC Educational Resources Information Center

Vecsey, Christopher G.; Park, Alan J.; Khatib, Nora; Abel, Ted

2015-01-01

Sleep deprivation (SD) following hippocampus-dependent learning in young mice impairs memory when tested the following day. Here, we examined the effects of SD on remote memory in both young and aged mice. In young mice, we found that memory is still impaired 1 mo after training. SD also impaired memory in aged mice 1 d after training, but, by a…

Efflux of creatine kinase from isolated soleus muscle depends on age, sex and type of exercise in mice.

PubMed

Baltusnikas, Juozas; Venckunas, Tomas; Kilikevicius, Audrius; Fokin, Andrej; Ratkevicius, Aivaras

2015-06-01

Elevated plasma creatine kinase (CK) activity is often used as an indicator of exercise-induced muscle damage. Our aim was to study effects of contraction type, sex and age on CK efflux from isolated skeletal muscles of mice. The soleus muscle (SOL) of adult (7.5-month old) female C57BL/6J mice was subjected to either 100 passive stretches, isometric contractions or eccentric contractions, and muscle CK efflux was assessed after two-hour incubation in vitro. SOL of young (3-month old) male and female mice was studied after 100 eccentric contractions. For adult females, muscle CK efflux was larger (p < 0.05) after eccentric contractions than after incubation without exercise (698 ± 344 vs. 268 ± 184 mU·h(-1), respectively), but smaller (p < 0.05) than for young females after the same type of exercise (1069 ± 341 mU·h(-1)). Eccentric exercise-induced CK efflux was larger in muscles of young males compared to young females (2046 ± 317 vs 1069 ± 341 mU · h(-1), respectively, p < 0.001). Our results show that eccentric contractions induce a significant increase in muscle CK efflux immediately after exercise. Isolated muscle resistance to exercise-induced CK efflux depends on age and sex of mice. Key pointsMuscle lengthening contractions induce the highest CK efflux in vitro compared with similar protocol of isometric contractions or passive stretches.Muscle CK efflux in vitro is applicable in studying changes of sarcolemma permeability/integrity, a proxy of muscle damage, in response to muscle contractile activity.Isolated muscle resistance to exercise-induced CK efflux is greater in female compared to male mice of young age and is further increased in adult female mice.

Efflux of Creatine Kinase from Isolated Soleus Muscle Depends on Age, Sex and Type of Exercise in Mice

PubMed Central

Baltusnikas, Juozas; Venckunas, Tomas; Kilikevicius, Audrius; Fokin, Andrej; Ratkevicius, Aivaras

2015-01-01

Elevated plasma creatine kinase (CK) activity is often used as an indicator of exercise-induced muscle damage. Our aim was to study effects of contraction type, sex and age on CK efflux from isolated skeletal muscles of mice. The soleus muscle (SOL) of adult (7.5-month old) female C57BL/6J mice was subjected to either 100 passive stretches, isometric contractions or eccentric contractions, and muscle CK efflux was assessed after two-hour incubation in vitro. SOL of young (3-month old) male and female mice was studied after 100 eccentric contractions. For adult females, muscle CK efflux was larger (p < 0.05) after eccentric contractions than after incubation without exercise (698 ± 344 vs. 268 ± 184 mU·h−1, respectively), but smaller (p < 0.05) than for young females after the same type of exercise (1069 ± 341 mU·h−1). Eccentric exercise-induced CK efflux was larger in muscles of young males compared to young females (2046 ± 317 vs 1069 ± 341 mU · h−1, respectively, p < 0.001). Our results show that eccentric contractions induce a significant increase in muscle CK efflux immediately after exercise. Isolated muscle resistance to exercise-induced CK efflux depends on age and sex of mice. Key points Muscle lengthening contractions induce the highest CK efflux in vitro compared with similar protocol of isometric contractions or passive stretches. Muscle CK efflux in vitro is applicable in studying changes of sarcolemma permeability/integrity, a proxy of muscle damage, in response to muscle contractile activity. Isolated muscle resistance to exercise-induced CK efflux is greater in female compared to male mice of young age and is further increased in adult female mice. PMID:25983588

Loss of Function of P2X7 Receptor Scavenger Activity in Aging Mice: A Novel Model for Investigating the Early Pathogenesis of Age-Related Macular Degeneration.

PubMed

Vessey, Kirstan A; Gu, Ben J; Jobling, Andrew I; Phipps, Joanna A; Greferath, Ursula; Tran, Mai X; Dixon, Michael A; Baird, Paul N; Guymer, Robyn H; Wiley, James S; Fletcher, Erica L

2017-08-01

Age-related macular degeneration (AMD) is a leading cause of irreversible, severe vision loss in Western countries. Recently, we identified a novel pathway involving P2X7 receptor scavenger function expressed on ocular immune cells as a risk factor for advanced AMD. In this study, we investigate the effect of loss of P2X7 receptor function on retinal structure and function during aging. P2X7-null and wild-type C57bl6J mice were investigated at 4, 12, and 18 months of age for macrophage phagocytosis activity, ocular histological changes, and retinal function. Phagocytosis activity of blood-borne macrophages decreased with age at 18 months in the wild-type mouse. Lack of P2X7 receptor function reduced phagocytosis at all ages compared to wild-type mice. At 12 months of age, P2X7-null mice had thickening of Bruchs membrane and retinal pigment epithelium dysfunction. By 18 months of age, P2X7-null mice displayed phenotypic characteristics consistent with early AMD, including Bruchs membrane thickening, retinal pigment epithelium cell loss, retinal functional deficits, and signs of subretinal inflammation. Our present study shows that loss of function of the P2X7 receptor in mice induces retinal changes representing characteristics of early AMD, providing a valuable model for investigating the role of scavenger receptor function and the immune system in the development of this age-related disease. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Locomotor activity and gait in aged mice deficient for type IX collagen

PubMed Central

Costello, Kerry E.; Guilak, Farshid; Griffin, Timothy M.

2010-01-01

Osteoarthritis (OA) is a risk factor for physical inactivity and impaired mobility, but it is not well understood how these locomotor behaviors are affected by the age of onset of OA and disease severity. Male mice homozygous for a Col9a1 gene inactivation (Col9a1−/−) develop early onset knee OA, increased tactile pain sensitivity, and gait alterations by 9 mo of age. We hypothesized that aged Col9a1−/− mice would reduce joint pain by adopting locomotor behaviors that reduce both the magnitude and daily frequency of joint loading. We tested this hypothesis by evaluating gait and spontaneous locomotor activity in 15- to 17-mo-old male Col9a1−/− (n = 5) and Col9a1+/+(WT) (n = 5) mice using well-controlled measures of voluntary activity in overground and running wheel conditions, as well as studies of gait in a velocity-controlled treadmill. We found no difference due to genotype in freely chosen locomotor velocity, stride frequency, hindfoot duty factor, dark phase activity time, or dark-phase travel distance during overground, running wheel, or speed-matched treadmill locomotion. Interpretation of these findings is potentially confounded by the observation that WT mice have greater knee OA than Col9a1−/− mice in the lateral tibial plateau by 17 mo of age. When accounting for individual differences in knee OA, functional locomotor impairments in aged Col9a1−/− and WT mice are manifested as reductions in total locomotor activity levels (e.g., both distance traveled and time active), particularly for wheel running. These results support the concept that current disease status, rather than age of disease onset, is the primary determinant of impaired locomotor activity with aging. PMID:20360435

Metabolic costs of mounting an antigen-stimulated immune response in adult and aged C57BL/6J mice.

PubMed

Demas, G E; Chefer, V; Talan, M I; Nelson, R J

1997-11-01

Animals must balance their energy budget despite seasonal changes in both energy availability and physiological expenditures. Immunity, in addition to growth, thermoregulation, and cellular maintenance, requires substantial energy to maintain function, although few studies have directly tested the energetic cost of immunity. The present study assessed the metabolic costs of an antibody response. Adult and aged male C5BL/6J mice were implanted with either empty Silastic capsules or capsules filled with melatonin and injected with either saline or keyhole limpet hemocyanin (KLH). O2 consumption was monitored periodically throughout antibody production using indirect calorimetry. KLH-injected mice mounted significant immunoglobulin G (IgG) responses and consumed more O2 compared with animals injected with saline. Melatonin treatment increased O2 consumption in mice injected with saline but suppressed the increased metabolic rate associated with an immune response in KLH-injected animals. Melatonin had no effect on immune response to KLH. Adult and aged mice did not differ in antibody response or metabolic activity. Aged mice appear unable to maintain sufficient heat production despite comparable O2 production to adult mice. These results suggest that mounting an immune response requires significant energy and therefore requires using resources that could otherwise be allocated to other physiological processes. Energetic trade-offs are likely when energy demands are high (e.g., during winter, pregnancy, or lactation). Melatonin appears to play an adaptive role in coordinating reproductive, immunologic, and energetic processes.

Shortened estrous cycle length, increased FSH levels, FSH variance, oocyte spindle aberrations, and early declining fertility in aging senescence-accelerated mouse prone-8 (SAMP8) mice: concomitant characteristics of human midlife female reproductive aging.

PubMed

Bernstein, Lori R; Mackenzie, Amelia C L; Kraemer, Duane C; Morley, John E; Farr, Susan; Chaffin, Charles L; Merchenthaler, István

2014-06-01

Women experience a series of specific transitions in their reproductive function with age. Shortening of the menstrual cycle begins in the mid to late 30s and is regarded as the first sign of reproductive aging. Other early changes include elevation and increased variance of serum FSH levels, increased incidences of oocyte spindle aberrations and aneuploidy, and declining fertility. The goal of this study was to investigate whether the mouse strain senescence-accelerated mouse-prone-8 (SAMP8) is a suitable model for the study of these midlife reproductive aging characteristics. Midlife SAMP8 mice aged 6.5-7.85 months (midlife SAMP8) exhibited shortened estrous cycles compared with SAMP8 mice aged 2-3 months (young SAMP8, P = .0040). Midlife SAMP8 mice had high FSH levels compared with young SAMP8 mice, and mice with a single day of high FSH exhibited statistically elevated FSH throughout the cycle, ranging from 1.8- to 3.6-fold elevation on the days of proestrus, estrus, metestrus, and diestrus (P < .05). Midlife SAMP8 mice displayed more variance in FSH than young SAMP8 mice (P = .01). Midlife SAMP8 ovulated fewer oocytes (P = .0155). SAMP8 oocytes stained with fluorescently labeled antitubulin antibodies and scored in fluorescence microscopy exhibited increased incidence of meiotic spindle aberrations with age, from 2/126 (1.59%) in young SAMP8 to 38/139 (27.3%) in midlife SAMP8 (17.2-fold increase, P < .0001). Finally, SAMP8 exhibited declining fertility from 8.9 pups/litter in young SAMP8 to 3.5 pups/litter in midlife SAMP8 mice (P < .0001). The age at which these changes occur is younger than for most mouse strains, and their simultaneous occurrence within a single strain has not been described previously. We propose that SAMP8 mice are a model of midlife human female reproductive aging.

Improved muscle function and quality after diet intervention with leucine-enriched whey and antioxidants in antioxidant deficient aged mice

PubMed Central

van Dijk, Miriam; Dijk, Francina J.; Bunschoten, Annelies; van Dartel, Dorien A.M.; van Norren, Klaske; Walrand, Stephane; Jourdan, Marion; Verlaan, Sjors; Luiking, Yvette

2016-01-01

Antioxidant (AOX) deficiencies are commonly observed in older adults and oxidative stress has been suggested to contribute to sarcopenia. Here we investigate if 1) low levels of dietary antioxidants had a negative impact on parameters of muscle mass, function and quality, and 2) to study if nutritional interventions with AOX and/or leucine-enriched whey protein could improve these muscle parameters in aged mice. 18-months-old mice were fed a casein-based antioxidant-deficient (lowox) diet or a casein-based control-diet (CTRL) for 7 months. During the last 3 months, lowox-mice were subjected to either: a) continued lowox, b) supplementation with vitamin A/E, Selenium and Zinc (AOX), c) substitution of casein with leucine-enriched whey protein (PROT) or d) a combination of both AOX and PROT (TOTAL). After 7 months lowox-mice displayed lower muscle strength and more muscle fatigue compared to CTRL. Compared to lowox-mice, PROT-mice showed improved muscle power, grip strength and less muscle fatigue. AOX-mice showed improved oxidative status, less muscle fatigue, improved grip strength and mitochondrial dynamics compared to lowox-mice. The TOTAL-mice showed the combined effects of both interventions compared to lowox-mice. In conclusion, nutritional intervention with AOX and/or leucine-enriched whey protein can play a role in improving muscle health in a AOX-deficient mouse model. PMID:26943770

Long-term Dietary Macronutrients and Hepatic Gene Expression in Aging Mice.

PubMed

Gokarn, Rahul; Solon-Biet, Samantha M; Cogger, Victoria C; Cooney, Gregory J; Wahl, Devin; McMahon, Aisling C; Mitchell, James R; Mitchell, Sarah J; Hine, Christopher; de Cabo, Rafael; Raubenheimer, David; Simpson, Stephen J; Le Couteur, David G

2018-04-23

Nutrition influences both hepatic function and aging, but mechanisms are poorly understood. Here, the effects of lifelong, ad libitum-fed diets varying in macronutrients and energy on hepatic gene expression were studied. Gene expression was measured using Affymetrix mouse arrays in livers of 46 mice aged 15 months fed one of 25 diets varying in protein, carbohydrates, fat, and energy density from 3 weeks of age. Gene expression was almost entirely influenced by protein intake. Carbohydrate and fat intake had few effects on gene expression compared with protein. Pathways and processes associated with protein intake included those involved with mitochondrial function, metabolic signaling (PI3K-Akt, AMPK, mTOR) and metabolism of protein and amino acids. Protein intake had variable effects on genes associated with regulation of longevity and influenced by caloric restriction. Among the genes of interest with expression that were significantly associated with protein intake are Cth, Gls2, Igf1, and Nnmt, which were increased with higher protein intake, and Igf2bp2, Fgf21, Prkab2, and Mtor, which were increased with lower protein intake. Dietary protein has a powerful impact on hepatic gene expression in older mice, with some overlap with genes previously reported to be involved with regulation of longevity or caloric restriction.

Merotelic kinetochore attachment in oocyte meiosis II causes sister chromatids segregation errors in aged mice.

PubMed

Cheng, Jin-Mei; Li, Jian; Tang, Ji-Xin; Hao, Xiao-Xia; Wang, Zhi-Peng; Sun, Tie-Cheng; Wang, Xiu-Xia; Zhang, Yan; Chen, Su-Ren; Liu, Yi-Xun

2017-08-03

Mammalian oocyte chromosomes undergo 2 meiotic divisions to generate haploid gametes. The frequency of chromosome segregation errors during meiosis I increase with age. However, little attention has been paid to the question of how aging affects sister chromatid segregation during oocyte meiosis II. More importantly, how aneuploid metaphase II (MII) oocytes from aged mice evade the spindle assembly checkpoint (SAC) mechanism to complete later meiosis II to form aneuploid embryos remains unknown. Here, we report that MII oocytes from naturally aged mice exhibited substantial errors in chromosome arrangement and configuration compared with young MII oocytes. Interestingly, these errors in aged oocytes had no impact on anaphase II onset and completion as well as 2-cell formation after parthenogenetic activation. Further study found that merotelic kinetochore attachment occurred more frequently and could stabilize the kinetochore-microtubule interaction to ensure SAC inactivation and anaphase II onset in aged MII oocytes. This orientation could persist largely during anaphase II in aged oocytes, leading to severe chromosome lagging and trailing as well as delay of anaphase II completion. Therefore, merotelic kinetochore attachment in oocyte meiosis II exacerbates age-related genetic instability and is a key source of age-dependent embryo aneuploidy and dysplasia.

Age-related changes in core body temperature and activity in triple-transgenic Alzheimer's disease (3xTgAD) mice.

PubMed

Knight, Elysse M; Brown, Timothy M; Gümüsgöz, Sarah; Smith, Jennifer C M; Waters, Elizabeth J; Allan, Stuart M; Lawrence, Catherine B

2013-01-01

Alzheimer's disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4-10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD.

Pressor response to angiotensin II is enhanced in aged mice and associated with inflammation, vasoconstriction and oxidative stress

PubMed Central

Dinh, Quynh Nhu; Drummond, Grant R.; Kemp-Harper, Barbara K.; Diep, Henry; Silva, T. Michael De; Kim, Hyun Ah; Vinh, Antony; Robertson, Avril A.B.; Cooper, Matthew A.; Mansell, Ashley

2017-01-01

Aging is commonly associated with chronic low-grade inflammation and hypertension but it is unknown whether a cause-effect relationship exists between them. We compared the sensitivity of young adult (8-12 w) and aged (23-31 mo) male C57Bl6J mice to develop hypertension in response to a slow-pressor dose of angiotensin II (Ang II; 0.28 mg/kg/d; 28 d). In young mice, the pressor response to Ang II was gradual and increased to 142±8 mmHg over 28 d. However, in aged mice, Ang II promptly increased SBP and reached 155±12 mmHg by 28 d. Aging increased renal but not brain expression of Ang II receptors (At1ar and At2r) and elevated AT1R:AT2R expression ratio in mesenteric artery. Maximal contractile responses of mesenteric arteries to Ang II were enhanced in aged mice and were not affected by L-NAME, indomethacin or tempol. Mesenteric arteries and thoracic aortae from aged mice exhibited higher Nox2-dependent superoxide production. Despite having higher renal expression of Nlrp3, Casp-1 and Il-1β, Ang II-induced hypertension (SBP: 139±7 mmHg) was unaffected by co-infusion of the NLRP3 inflammasome inhibitor, MCC950 (10 mg/kg/d; SBP: 145±10 mmHg). Thus, increased vascular AT1R:AT2R expression, rather than NLRP3 inflammasome activation, may contribute to enhanced responses to Ang II in aging. PMID:28659507

Pressor response to angiotensin II is enhanced in aged mice and associated with inflammation, vasoconstriction and oxidative stress.

PubMed

Dinh, Quynh Nhu; Drummond, Grant R; Kemp-Harper, Barbara K; Diep, Henry; De Silva, T Michael; Kim, Hyun Ah; Vinh, Antony; Robertson, Avril A B; Cooper, Matthew A; Mansell, Ashley; Chrissobolis, Sophocles; Sobey, Christopher G

2017-06-28

Aging is commonly associated with chronic low-grade inflammation and hypertension but it is unknown whether a cause-effect relationship exists between them. We compared the sensitivity of young adult (8-12 w) and aged (23-31 mo) male C57Bl6J mice to develop hypertension in response to a slow-pressor dose of angiotensin II (Ang II; 0.28 mg/kg/d; 28 d). In young mice, the pressor response to Ang II was gradual and increased to 142±8 mmHg over 28 d. However, in aged mice, Ang II promptly increased SBP and reached 155±12 mmHg by 28 d. Aging increased renal but not brain expression of Ang II receptors ( At1ar and At2r ) and elevated AT1R:AT2R expression ratio in mesenteric artery. Maximal contractile responses of mesenteric arteries to Ang II were enhanced in aged mice and were not affected by L-NAME, indomethacin or tempol. Mesenteric arteries and thoracic aortae from aged mice exhibited higher Nox2-dependent superoxide production. Despite having higher renal expression of Nlrp3, Casp-1 and Il-1β , Ang II-induced hypertension (SBP: 139±7 mmHg) was unaffected by co-infusion of the NLRP3 inflammasome inhibitor, MCC950 (10 mg/kg/d; SBP: 145±10 mmHg). Thus, increased vascular AT1R:AT2R expression, rather than NLRP3 inflammasome activation, may contribute to enhanced responses to Ang II in aging.

Age-dependent effects on sensory axonal excitability in normal mice.

PubMed

Banzrai, Chimeglkham; Nodera, Hiroyuki; Higashi, Saki; Okada, Ryo; Osaki, Yusuke; Mori, Atsuko; Kaji, Ryuji

2016-01-12

Serial recordings were performed to measure sensory excitability in peripheral nerves and elucidate age-dependent changes in neuronal ion currents in the peripheral sensory nervous system. The threshold tracking technique was used to measure multiple excitability indices in the tail sensory nerves of five normal male mice at four time points (6, 10, 14, and 19 weeks of age). A separate group of four mice was also measured at 43 weeks and at 60 weeks of age. Maturation was accompanied by an increase in early hyperpolarization and superexcitability at 10 weeks. At 60 weeks, the hyperpolarizing electrotonus shifted downward, while superexcitability became greater and subexcitability (double stimuli) decreased. Computer modeling showed that the most notable age-related interval changes in excitability parameters were Barrett-Barrett, H, and slow K(+) conductances. Understanding age-related changes in the excitability of sensory axons may provide a platform for understanding age-dependent sensory symptoms and developing age-specific channel-targeting therapies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Mice over-expressing BDNF in forebrain neurons develop an altered behavioral phenotype with age.

PubMed

Weidner, Kate L; Buenaventura, Diego F; Chadman, Kathryn K

2014-07-15

Evidence from clinical studies suggests that abnormal activity of brain derived neurotrophic factor (BDNF) contributes to the pathogenesis of autism spectrum disorders (ASDs). A genetically modified line of mice over-expressing a BDNF transgene in forebrain neurons was used to investigate if this mutation leads to changes in behavior consistent with ASD. The mice used in these experiments were behaviorally tested past 5 months of age when spontaneous seizures were evident. These seizures were not observed in age-matched wildtype (WT) mice or younger mice from this transgenic line. The BDNF mice in these experiments weighed less than their WT littermates. The BDNF transgenic (BDNF-tg) mice demonstrated similar levels of sociability in the social approach test. Conversely, the BDNF-tg mice demonstrated less obsessive compulsive-like behavior in the marble burying test, less anxiety-like behavior in the elevated plus maze test, and less depressive-like behavior in the forced swim test. Changes in behavior were found in these older mice that have not been observed in younger mice from this transgenic line, which may be due to the development of seizures as the mice age. These mice do not have an ASD phenotype but may be useful to study adult onset epilepsy. Copyright © 2014 Elsevier B.V. All rights reserved.

The Cardioprotective Effect of Vitamin E (Alpha-Tocopherol) Is Strongly Related to Age and Gender in Mice

PubMed Central

Li, Yan; Lin, Ze-Bang; Liu, Xiang; Wang, Jing-Feng; Chen, Yang-Xin; Wang, Zhi-Ping; Zhang, Xi; Ou, Zhi-Jun; Ou, Jing-Song

2015-01-01

Vitamin E (VitE) only prevented cardiovascular diseases in some patients and the mechanisms remain unknown. VitE levels can be affected by aging and gender. We hypothesize that age and gender can influence VitE’s cardioprotective effect. Mice were divided into 4 groups according to age and gender, and each group of mice were divided into a control group and a VitE group. The mice were administered water or VitE for 21 days; Afterward, the cardiac function and myocardial infarct size and cardiomyocyte apoptosis were measured after myocardial ischemia reperfusion(MI/R). VitE may significantly improved cardiac function in young male mice and aged female mice by enhancing ERK1/2 activity and reducing JNK activity. Enhanced expression of HSP90 and Bcl-2 were also seen in young male mice. No changes in cardiac function and cardiac proteins were detected in aged male mice and VitE was even liked to exert a reverse effect in cardiac function in young mice by enhancing JNK activity and reducing Bcl-2 expression. Those effects were in accordance with the changes of myocardial infarction size and cardiomyocyte apoptosis in each group of mice. VitE may reduce MI/R injury by inhibiting cardiomyocyte apoptosis in young male mice and aged female mice but not in aged male mice. VitE was possibly harmful for young female mice, shown as increased cardiomyocyte apoptosis after MI/R. Thus, we speculated that the efficacy of VitE in cardiac protection was associated with age and gender. PMID:26331272

No dramatic age-related loss of hair cells and spiral ganglion neurons in Bcl-2 over-expression mice or Bax null mice

PubMed Central

2010-01-01

Age-related decline of neuronal function is associated with age-related structural changes. In the central nervous system, age-related decline of cognitive performance is thought to be caused by synaptic loss instead of neuronal loss. However, in the cochlea, age-related loss of hair cells and spiral ganglion neurons (SGNs) is consistently observed in a variety of species, including humans. Since age-related loss of these cells is a major contributing factor to presbycusis, it is important to study possible molecular mechanisms underlying this age-related cell death. Previous studies suggested that apoptotic pathways were involved in age-related loss of hair cells and SGNs. In the present study, we examined the role of Bcl-2 gene in age-related hearing loss. In one transgenic mouse line over-expressing human Bcl-2, there were no significant differences between transgenic mice and wild type littermate controls in their hearing thresholds during aging. Histological analysis of the hair cells and SGNs showed no significant conservation of these cells in transgenic animals compared to the wild type controls during aging. These data suggest that Bcl-2 overexpression has no significant effect on age-related loss of hair cells and SGNs. We also found no delay of age-related hearing loss in mice lacking Bax gene. These findings suggest that age-related hearing loss is not through an apoptotic pathway involving key members of Bcl-2 family. PMID:20637089

Aging Exacerbates Obesity-induced Cerebromicrovascular Rarefaction, Neurovascular Uncoupling, and Cognitive Decline in Mice

PubMed Central

Tucsek, Zsuzsanna; Toth, Peter; Tarantini, Stefano; Sosnowska, Danuta; Gautam, Tripti; Warrington, Junie P.; Giles, Cory B.; Wren, Jonathan D.; Koller, Akos; Ballabh, Praveen; Sonntag, William E.; Csiszar, Anna

2014-01-01

Epidemiological studies show that obesity has deleterious effects on the brain and cognitive function in the elderly population. However, the specific mechanisms through which aging and obesity interact to promote cognitive decline remain unclear. To test the hypothesis that aging exacerbates obesity-induced cerebromicrovascular impairment, we compared young (7 months) and aged (24 months) high-fat diet–fed obese C57BL/6 mice. We found that aging exacerbates the obesity-induced decline in microvascular density both in the hippocampus and in the cortex. The extent of hippocampal microvascular rarefaction and the extent of impairment of hippocampal-dependent cognitive function positively correlate. Aging exacerbates obesity-induced loss of pericyte coverage on cerebral microvessels and alters hippocampal angiogenic gene expression signature, which likely contributes to microvascular rarefaction. Aging also exacerbates obesity-induced oxidative stress and induction of NADPH oxidase and impairs cerebral blood flow responses to whisker stimulation. Collectively, obesity exerts deleterious cerebrovascular effects in aged mice, promoting cerebromicrovascular rarefaction and neurovascular uncoupling. The morphological and functional impairment of the cerebral microvasculature in association with increased blood–brain barrier disruption and neuroinflammation (Tucsek Z, Toth P, Sosnowsk D, et al. Obesity in aging exacerbates blood–brain barrier disruption, neuroinflammation and oxidative stress in the mouse hippocampus: effects on expression of genes involved in beta-amyloid generation and Alzheimer’s disease. J Gerontol Biol Med Sci. 2013. In press, PMID: 24269929) likely contribute to obesity-induced cognitive decline in aging. PMID:24895269

Flow cytometry and immunomorphological characteristics of apoptosis in hepatocytes of white mice during aging.

PubMed

Gujabidze, N; Rukhadze, R

2006-08-01

Apoptosis, sometimes called "programmed cell death", the process that goes on continuously throughout life has received phenomenal attention in the past few years. In the process of aging of organism, most of organs undergo morphological and functional changes at various frequencies. Initially, the role of apoptosis regarding aging was evaluated negatively, however, at present the issue is in the process of reconsideration. The experiments were performed on 74 white mice, distributed in three age groups (juveniles, adults, and senescents). Apoptotic nuclei were detected by immunomorphological and flow cytometry assay. So, the analysis of the data obtained that apoptosis in hepatocytes of white mice decreases with age and afterwards increases in a credible way. The maximum value is reached in the senescent mice. It has been considered, that aging increases the susceptibility of hepatocytes to apoptosis in white mice.

Age-related differences in interferon regulatory factor-4 and -5 signaling in ischemic brains of mice.

PubMed

Zhao, Shou-Cai; Wang, Chun; Xu, Heng; Wu, Wen-Qian; Chu, Zhao-Hu; Ma, Ling-Song; Zhang, Ying-Dong; Liu, Fudong

2017-11-01

Stroke is a disease that mainly affects the elderly. Since the age-related differences in stroke have not been well studied, modeling stroke in aged animals is clinically more relevant. The inflammatory responses to stroke are a fundamental pathological procedure, in which microglial activation plays an important role. Interferon regulatory factor-5 (IRF5) and IRF4 regulate M1 and M2 activation of macrophages, respectively, in peripheral inflammation; but it is unknown whether IRF5/IRF4 are also involved in cerebral inflammatory responses to stroke and whether age-related differences of the IRF5/IRF4 signaling exist in ischemic brain. Here, we investigated the influences of aging on IRF5/IRF4 signaling and post-stroke inflammation in mice. Both young (9-12 weeks) and aged (18 months) male mice were subjected to middle cerebral artery occlusion (MCAO). Morphological and biochemical changes in the ischemic brains and behavior deficits were assessed on 1, 3, and 7 d post-stroke. After MCAO, the aged mice showed smaller infarct sizes but higher neurological deficits and corner test scores than young mice. Young mice had higher levels of IRF4 and CD206 microglia in the ischemic brains, whereas the aged mice expressed more IRF5 and MHCII microglia. After MCAO, serum pro-inflammatory cytokines (TNF-α, iNOS, IL-6) were more prominently up-regulated in aged mice, whereas serum anti-inflammatory cytokines (TGF-β, IL-4, IL-10) were more prominently up-regulated in young mice. Our results demonstrate that aging has a significant influence on stroke outcomes in mice, which is probably mediated by age-specific inflammatory responses.

GPR30 activation improves memory and facilitates DHPG-induced LTD in the hippocampal CA3 of middle-aged mice.

PubMed

Xu, Wen; Cao, Jian; Zhou, Yan; Wang, Lina; Zhu, Guoqi

2018-03-01

Reduced estrogen levels and decreased expression of related receptors are typical cerebral features of aging. The G protein-coupled estrogen receptor 1 (GPER1, also known as GPR30) is considered a novel therapeutic target for neurodegenerative diseases. In this study, we demonstrated that hippocampal GPR30 expression was reduced in middle-aged mice compared with young adult mice. GPR30 agonist G1 improved both fear and spatial memory in both male and female middle-aged mice, but not in young adult mice, which were blocked by the GPR30 antagonist G15. Interestingly, a group I metabotropic glutamate receptor (mGluR) agonist, 3,5-dihydroxyphenylglycine (DHPG)-induced long-term depression (LTD) in mossy fiber-cornu ammonis 3 (MF-CA3) synapses but not Schaffer collateral-CA1 (SC-CA1) synapses was facilitated in brain slices from G1-treated middle-aged mice. Long-term potentiation (LTP) in SC-CA1 synapses was not affected in slices from G1-treated mice. The effects of GPR30 activation on memory and DHPG-LTD in MF-CA3 synapses were further confirmed by viral expression of GPR30 in the CA3. The regulation of hippocampal synaptic plasticity by G1 treatment might be related to brain-derived neurotrophic factor (BDNF)-tropomyosin receptor kinase B (TrkB) signaling, as G15 also blocked G1-induced activation of the BDNF-TrkB pathway. Moreover, we found that DHPG triggered GluA internalization in slices from G1-treated mice but not control mice. Pharmacological experiments showed that G1-mediated facilitation of DHPG-induced LTD in MF-CA3 synapses was dependent on protein kinase B (Akt), mammalian target of rapamycin (mTor), and TrkB signaling. In conclusion, our results indicate that GPR30 activation improves memory in middle-aged mice, likely through facilitating synaptic plasticity in the CA3. This study provides novel evidence that GPR30 activation can improve memory in middle-aged animals. Copyright © 2018 Elsevier Inc. All rights reserved.

Altered Hippocampal Transcript Profile Accompanies an Age-Related Spatial Memory Deficit in Mice

ERIC Educational Resources Information Center

Verbitsky, Miguel; Yonan, Amanda L.; Malleret, Gael; Kandel, Eric R.; Gilliam, T. Conrad; Pavlidis, Paul

2004-01-01

We have carried out a global survey of age-related changes in mRNA levels in the 57BL/6NIA mouse hippocampus and found a difference in the hippocampal gene expression profile between 2-month-old young mice and 15-month-old middle-aged mice correlated with an age-related cognitive deficit in hippocampal-based explicit memory formation. Middle-aged…

Acetaminophen hepatotoxicity in mice: Effect of age, frailty and exposure type

PubMed Central

Kane, Alice E.; Mitchell, Sarah J.; Mach, John; Huizer-Pajkos, Aniko; McKenzie, Catriona; Jones, Brett; Cogger, Victoria; Le Couteur, David G.; de Cabo, Rafael; Hilmer, Sarah N.

2018-01-01

Acetaminophen is a commonly used analgesic that can cause severe hepatotoxicity in overdose. Despite old age and frailty being associated with extensive and long-term utilization of acetaminophen and a high prevalence of adverse drug reactions, there is limited information on the risks of toxicity from acetaminophen in old age and frailty. This study aimed to assess changes in the risk and mechanisms of hepatotoxicity from acute, chronic and sub-acute acetaminophen exposure with old age and frailty in mice. Young and old male C57BL/6 mice were exposed to either acute (300 mg/kg via oral gavage), chronic (100 mg/kg/day in diet for six weeks) or sub-acute (250 mg/kg, t.i.d., for three days) acetaminophen, or saline control. Pre-dosing mice were scored for the mouse clinical frailty index, and after dosing serum and liver tissue were collected for assessment of toxicity and mechanisms. There were no differences with old age or frailty in the degree of hepatotoxicity induced by acute, chronic or subacute acetaminophen exposure as assessed by serum liver enzymes and histology. Age-related changes in the acetaminophen toxicity pathways included increased liver GSH concentrations, increased NQO1 activity and an increased pro- and anti-inflammatory response to acetaminophen in old age. Frailty-related changes included a negative correlation between frailty index and serum protein, albumin and ALP concentrations for some mouse groups. In conclusion, although there were changes in some pathways that would be expected to influence susceptibility to acetaminophen toxicity, there was no overall increase in acetaminophen hepatotoxicity with old age or frailty in mice. PMID:26615879

Age-related changes in core body temperature and activity in triple-transgenic Alzheimer’s disease (3xTgAD) mice

PubMed Central

Knight, Elysse M.; Brown, Timothy M.; Gümüsgöz, Sarah; Smith, Jennifer C. M.; Waters, Elizabeth J.; Allan, Stuart M.; Lawrence, Catherine B.

2013-01-01

SUMMARY Alzheimer’s disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4–10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD. PMID:22864021

Ablation of the Sam68 RNA Binding Protein Protects Mice from Age-Related Bone Loss

PubMed Central

Richard, Stéphane; Torabi, Nazi; Franco, Gladys Valverde; Tremblay, Guy A; Chen, Taiping; Vogel, Gillian; Morel, Mélanie; Cléroux, Patrick; Forget-Richard, Alexandre; Komarova, Svetlana; Tremblay, Michel L; Li, Wei; Li, Ailian; Gao, Yun Jing; Henderson, Janet E

2005-01-01

The Src substrate associated in mitosis of 68 kDa (Sam68) is a KH-type RNA binding protein that has been shown to regulate several aspects of RNA metabolism; however, its physiologic role has remained elusive. Herein we report the generation of Sam68-null mice by homologous recombination. Aged Sam68−/− mice preserved their bone mass, in sharp contrast with 12-month-old wild-type littermates in which bone mass was decreased up to approximately 75%. In fact, the bone volume of the 12-month-old Sam68−/− mice was virtually indistinguishable from that of 4-month-old wild-type or Sam68−/− mice. Sam68−/− bone marrow stromal cells had a differentiation advantage for the osteogenic pathway. Moreover, the knockdown of Sam68 using short hairpin RNA in the embryonic mesenchymal multipotential progenitor C3H10T1/2 cells resulted in more pronounced expression of the mature osteoblast marker osteocalcin when differentiation was induced with bone morphogenetic protein-2. Cultures of mouse embryo fibroblasts generated from Sam68+/+ and Sam68−/− littermates were induced to differentiate into adipocytes with culture medium containing pioglitazone and the Sam68−/− mouse embryo fibroblasts shown to have impaired adipocyte differentiation. Furthermore, in vivo it was shown that sections of bone from 12-month-old Sam68−/− mice had few marrow adipocytes compared with their age-matched wild-type littermate controls, which exhibited fatty bone marrow. Our findings identify endogenous Sam68 as a positive regulator of adipocyte differentiation and a negative regulator of osteoblast differentiation, which is consistent with Sam68 being a modulator of bone marrow mesenchymal cell differentiation, and hence bone metabolism, in aged mice. PMID:16362077

Aging rather than stress strongly influences amino acid metabolisms in the brain and genital organs of female mice.

PubMed

Kodaira, Momoko; Nagasawa, Mao; Yamaguchi, Takeshi; Ikeda, Hiromi; Minaminaka, Kimie; Chowdhury, Vishwajit S; Yasuo, Shinobu; Furuse, Mitsuhiro

2017-03-01

Aging and stress affect quality of life, and proper nourishment is one of means of preventing this effect. Today, there is a focus on the amount of protein consumed by elderly people; however, changes in the amino acid metabolism of individuals have not been fully considered. In addition, the difference between average life span and healthy life years is larger in females than it is in males. To prolong the healthy life years of females, in the present study we evaluated the influence of stress and aging on metabolism and emotional behavior by comparing young and middle-aged female mice. After 28 consecutive days of immobilization stress, behavioral tests were conducted and tissue sampling was performed. The results showed that the body weight of middle-aged mice was severely lowered by stress, but emotional behaviors were hardly influenced by either aging or stress. Aging influenced changes in amino acid metabolism in the brain and increased various amino acid levels in the uterus and ovary. In conclusion, we found that aged mice were more susceptible to stress in terms of body-weight reduction, and that amino acid metabolisms in the brain and genital organs were largely influenced by aging rather than by stress. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Reduced mastication stimulates impairment of spatial memory and degeneration of hippocampal neurons in aged SAMP8 mice.

PubMed

Onozuka, M; Watanabe, K; Mirbod, S M; Ozono, S; Nishiyama, K; Karasawa, N; Nagatsu, I

1999-04-24

The involvement of reduced mastication in senile dementia was evaluated by examining the effect of cutting off the upper molars (molarless) on spatial memory and numbers of hippocampal neurons in aged SAMP8 mice. Molarless mice showed a decrease in both learning ability in a water maze and neuron density in the hippocampal CA1 region compared with control mice. These changes increased the longer the molarless condition persisted. The data suggest a possible link between reduced mastication and hippocampal neuron loss that may be one risk factor for senile impairment of spatial memory. Copyright 1999 Elsevier Science B.V.

Effect of Lactobacillus johnsonii La1 on immune function and serum albumin in aged and malnourished aged mice.

PubMed

Kaburagi, Tomoko; Yamano, Toshihiko; Fukushima, Yoichi; Yoshino, Haruka; Mito, Natsuko; Sato, Kazuto

2007-04-01

Protein-energy malnutrition (PEM) is a serious nutritional problem that causes immune dysfunction in elderly people. Probiotic lactic acid bacteria may potentially modify immunity; however, there is little evidence to elucidate the influence of these bacteria on PEM in the elderly. The immune modulation effects of lactic acid bacterium Lactobacillus johnsonii La1 (La1) were examined in aged mice and aged mice with PEM. Twenty-month-old male 57BL6/n mice (n = 28) were divided into four groups and received the following diet for 14 d: a complete diet (20% protein) without Lal (control) or with Lal or a low-protein diet (5% protein) to induce PEM, with or without La1. All mice were immunized with diphtheria toxin (DT) with alfacalciferol at 7 d and sacrificed 14 d after starting the experimental diets. Serum albumin concentrations and body weight, both of which were reduced by the low-protein diet, were ameliorated by La1 intake and were the same as in mice receiving the control diet. Anti-DT immunoglobulin (Ig) A in fecal extract was increased by La1 intake in mice receiving the complete and low-protein diets. Serum anti-DT IgA, IgG, splenocyte proliferation, and CD8(+) T cells were reduced by the low-protein diet and restored by La1 intake. La1 enhances intestinal IgA production and helps recover nutritional status and systemic immune responses in aged mice with PEM. It is possible that La1 may contribute to immune system recovery in immunocompromised hosts such as elderly humans with PEM.

Human umbilical cord plasma proteins revitalize hippocampal function in aged mice

PubMed Central

Castellano, Joseph M.; Mosher, Kira I.; Abbey, Rachelle J.; McBride, Alisha A.; James, Michelle L.; Berdnik, Daniela; Shen, Jadon C.; Zou, Bende; Xie, Xinmin S.; Tingle, Martha; Hinkson, Izumi V.; Angst, Martin S.; Wyss-Coray, Tony

2017-01-01

Ageing drives changes in neuronal and cognitive function, the decline of which is a major feature of many neurological disorders. The hippocampus, a brain region subserving roles of spatial and episodic memory and learning, is sensitive to the detrimental effects of ageing at morphological and molecular levels. With advancing age, synapses in various hippocampal subfields exhibit impaired long-term potentiation1, an electrophysiological correlate of learning and memory. At the molecular level, immediate early genes are among the synaptic plasticity genes that are both induced by long-term potentiation2, 3, 4 and downregulated in the aged brain5, 6, 7, 8. In addition to revitalizing other aged tissues9, 10, 11, 12, 13, exposure to factors in young blood counteracts age-related changes in these central nervous system parameters14, 15, 16, although the identities of specific cognition-promoting factors or whether such activity exists in human plasma remains unknown17. We hypothesized that plasma of an early developmental stage, namely umbilical cord plasma, provides a reservoir of such plasticity-promoting proteins. Here we show that human cord plasma treatment revitalizes the hippocampus and improves cognitive function in aged mice. Tissue inhibitor of metalloproteinases 2 (TIMP2), a blood-borne factor enriched in human cord plasma, young mouse plasma, and young mouse hippocampi, appears in the brain after systemic administration and increases synaptic plasticity and hippocampal-dependent cognition in aged mice. Depletion experiments in aged mice revealed TIMP2 to be necessary for the cognitive benefits conferred by cord plasma. We find that systemic pools of TIMP2 are necessary for spatial memory in young mice, while treatment of brain slices with TIMP2 antibody prevents long-term potentiation, arguing for previously unknown roles for TIMP2 in normal hippocampal function. Our findings reveal that human cord plasma contains plasticity-enhancing proteins of high

Expansion of myeloid-derived suppressor cells with aging in the bone marrow of mice through a NF-κB-dependent mechanism.

PubMed

Flores, Rafael R; Clauson, Cheryl L; Cho, Joonseok; Lee, Byeong-Chel; McGowan, Sara J; Baker, Darren J; Niedernhofer, Laura J; Robbins, Paul D

2017-06-01

With aging, there is progressive loss of tissue homeostasis and functional reserve, leading to an impaired response to stress and an increased risk of morbidity and mortality. A key mediator of the cellular response to damage and stress is the transcription factor NF-κB. We demonstrated previously that NF-κB transcriptional activity is upregulated in tissues from both natural aged mice and in a mouse model of a human progeroid syndrome caused by defective repair of DNA damage (ERCC1-deficient mice). We also demonstrated that genetic reduction in the level of the NF-κB subunit p65(RelA) in the Ercc1 -/∆ progeroid mouse model of accelerated aging delayed the onset of age-related pathology including muscle wasting, osteoporosis, and intervertebral disk degeneration. Here, we report that the largest fraction of NF-κB -expressing cells in the bone marrow (BM) of aged (>2 year old) mice (C57BL/6-NF-κB EGFP reporter mice) are Gr-1 + CD11b + myeloid-derived suppressor cells (MDSCs). There was a significant increase in the overall percentage of MDSC present in the BM of aged animals compared with young, a trend also observed in the spleen. However, the function of these cells appears not to be compromised in aged mice. A similar increase of MDSC was observed in BM of progeroid Ercc1 -/∆ and BubR1 H/H mice. The increase in MDSC in Ercc1 -/∆ mice was abrogated by heterozygosity in the p65/RelA subunit of NF-κB. These results suggest that NF-κB activation with aging, at least in part, drives an increase in the percentage of MDSCs, a cell type able to suppress immune cell responses. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Subcutaneous Compared with Intraperitoneal KetamineXylazine for Anesthesia of Mice.

PubMed

Levin-Arama, Maya; Abraham, Lital; Waner, Trevor; Harmelin, Alon; Steinberg, David M; Lahav, Tal; Harlev, Mickey

2016-11-01

Mice are commonly anesthetized intraperitoneally with a ketamine-xylazine (KX) solution. Although this route of administration allows rapid uptake of the injected drugs, its disadvantages and potential risks include pain, peritoneal irritation, and perforation of an abdominal organ; some of the risks depend on the operator's experience. We compared the efficacy of intraperitoneal and subcutaneous administration of KX in HSD:ICR, BALB/cOlaHsd, and C57BL/6JOlaHsd mice in terms of time to onset and duration of surgical anesthesia, procedure safety, and mortality. Male and female mice (n = 20 each sex and strain) were anesthetized by using the same dose of intraperitoneal or subcutaneous KX. Time to onset and duration of immobilization and time to onset and duration of surgical anesthesia according to the pedal reflex differed significantly between strains. Within each strain, the durations of immobilization and surgical anesthesia were comparable between the routes of administration. The sex of the mouse but not the route of administration influenced whether surgical anesthesia was achieved. None of the subcutaneously-injected mice died. After intraperitoneal injections, 30% of the female mice died, compared with 3% of the male. In addition, fewer female mice achieved surgical anesthesia, suggesting a narrow therapeutic window for intraperitoneal KX in female mice. In conclusion, surgical anesthesia of mice with subcutaneous KX (K, 191.25 mg/kg; X, 4.25 mg/kg) seems to be safe, and the subcutaneous route is generally just as effective as the intraperitoneal route. The variability among mouse strains and between sexes requires further investigation to determine the optimal dosage.

Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling

PubMed Central

Koopman, Jacob J.E.; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S.; Sun, Liou Y.; Bartke, Andrzej

2016-01-01

Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species. PMID:26959761

Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling.

PubMed

Koopman, Jacob J E; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S; Sun, Liou Y; Bartke, Andrzej

2016-03-01

Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species.

Characterizing age-related decline of recognition memory and brain activation profile in mice.

PubMed

Belblidia, Hassina; Leger, Marianne; Abdelmalek, Abdelouadoud; Quiedeville, Anne; Calocer, Floriane; Boulouard, Michel; Jozet-Alves, Christelle; Freret, Thomas; Schumann-Bard, Pascale

2018-06-01

Episodic memory decline is one of the earlier deficits occurring during normal aging in humans. The question of spatial versus non-spatial sensitivity to age-related memory decline is of importance for a full understanding of these changes. Here, we characterized the effect of normal aging on both non-spatial (object) and spatial (object location) memory performances as well as on associated neuronal activation in mice. Novel-object (NOR) and object-location (OLR) recognition tests, respectively assessing the identity and spatial features of object memory, were examined at different ages. We show that memory performances in both tests were altered by aging as early as 15 months of age: NOR memory was partially impaired whereas OLR memory was found to be fully disrupted at 15 months of age. Brain activation profiles were assessed for both tests using immunohistochemical detection of c-Fos (neuronal activation marker) in 3and 15 month-old mice. Normal performances in NOR task by 3 month-old mice were associated to an activation of the hippocampus and a trend towards an activation in the perirhinal cortex, in a way that did significantly differ with 15 month-old mice. During OLR task, brain activation took place in the hippocampus in 3 month-old but not significantly in 15 month-old mice, which were fully impaired at this task. These differential alterations of the object- and object-location recognition memory may be linked to differential alteration of the neuronal networks supporting these tasks. Copyright © 2018 Elsevier Inc. All rights reserved.

Inflammatory and age-related pathologies in mice with ectopic expression of human PARP-1.

PubMed

Mangerich, Aswin; Herbach, Nadja; Hanf, Benjamin; Fischbach, Arthur; Popp, Oliver; Moreno-Villanueva, María; Bruns, Oliver T; Bürkle, Alexander

2010-06-01

Poly(ADP-ribose) polymerase-1 (PARP-1) is a sensor for DNA strand breaks and some unusual DNA structures and catalyzes poly(ADP-ribosyl)ation of nuclear proteins with NAD(+) serving as substrate. PARP-1 is involved in the regulation of genomic integrity, transcription, inflammation, and cell death. Due to its versatile role, PARP-1 is discussed both as a longevity factor and as an aging-promoting factor. Recently, we generated a mouse model with ectopic integration of full-length hPARP-1 [Mangerich, A., Scherthan, H., Diefenbach, J., Kloz, U., van der Hoeven, F., Beneke, S. and Bürkle, A., 2009. A caveat in mouse genetic engineering: ectopic gene targeting in ES cells by bidirectional extension of the homology arms of a gene replacement vector carrying human PARP-1. Transgenic Res. 18, 261-279]. Here, we show that hPARP-1 mice exhibit impaired survival rates accompanied by reduced hair growth and premature development of several inflammation and age-associated pathologies, such as adiposity, kyphosis, nephropathy, dermatitis, pneumonitis, cardiomyopathy, hepatitis, and anemia. Moreover, mutant male mice showed impaired glucose tolerance, yet without developing manifest diabetes. Overall tumor burden was comparable in wild-type and hPARP-1 mice, but tumor spectrum was shifted in mutant mice, showing lower incidence of sarcomas, but increased incidence of carcinomas. Furthermore, DNA repair was delayed in splenocytes of hPARP-1 mice, and gene expression of pro-inflammatory cytokines was dysregulated. Our results suggest that in hPARP-1 mice impaired DNA repair, accompanied by a continuous low-level increase in pro-inflammatory stimuli, causes development of chronic diseases leading to impaired survival. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Aging-related renal injury and inflammation are associated with downregulation of Klotho and induction of RIG-I/NF-κB signaling pathway in senescence-accelerated mice.

PubMed

Zeng, Yi; Wang, Ping-Han; Zhang, Mao; Du, Jun-Rong

2016-02-01

The predominant distribution of the antiaging Klotho protein in both the kidneys and brain may point to its essential role in protecting against dysfunction of the kidney-brain axis during the aging process. Our previous study showed that the downregulation of Klotho was involved in aging-related cognitive impairment in aged senescence-accelerated mouse prone-8 (SAMP8) mice. The present study investigated the potential role of Klotho in aging-associated inflammation and renal injury. Age- and gender-matched groups of SAMP8 mice and their corresponding normal control senescence-accelerated mouse resistant-1 (SAMR1) were used to investigate the potential role of Klotho in aging-associated inflammation and renal injury. Compared with aged SAMR1 controls, early-stage chronic kidney disease (CKD), which is associated with an increase in the urinary albumin-to-creatinine ratio, inflammatory cell infiltration, glomerulosclerosis, and tubulointerstitial fibrosis, was observed in aged SAMP8 mice. Furthermore, the aging-related loss of Klotho-induced activation of the retinoic acid-inducible gene 1/nuclear factor-κB (RIG-I/NF-κB) signaling pathway and subsequent production of the proinflammatory mediators tumor necrosis factor α, interleukin-6, and inducible nitric oxide synthase in the kidneys of aged SAMP8 mice compared with SAMR1 controls. The present results suggest that aging-related inflammation and the development of early-stage CKD are likely associated with the downregulation of Klotho and induction of the RIG-I/NF-κB signaling pathway in 12-month-old SAMP8 mice. Moreover, aged SAMP8 mice with cognitive deficits and renal damage may be a potential mouse model for investigating the kidney-brain axis in the aging process.

Age and exposure to arsenic alter base excision repair transcript levels in mice.

PubMed

Osmond, Megan J; Kunz, Bernard A; Snow, Elizabeth T

2010-09-01

Arsenic (As) induces DNA-damaging reactive oxygen species. Most oxidative DNA damage is countered by base excision repair (BER), the capacity for which may be reduced in older animals. We examined whether age and consumption of As in lactational milk or drinking water influences BER gene transcript levels in mice. Lactating mothers and 24-week-old mice were exposed (24 h or 2 weeks) to As (2 or 50 p.p.m.) in drinking water. Lung tissue was harvested from adults, neonates (initially 1 week old) feeding from lactating mothers and untreated animals 1-26 weeks old. Transcripts encoding BER proteins were quantified. BER transcript levels decreased precipitously with age in untreated mice but increased in neonates whose mothers were exposed to 50 p.p.m. As for 24 h or 2 weeks. Treatment of 24-week-old mice with 2 or 50 p.p.m. As for 2 weeks decreased all transcript levels measured. Exposure to As attenuated the age-related transcript level decline for only one BER gene. We conclude that aging is associated with a rapid reduction of BER transcript levels in mice, which may contribute to decreased BER activity in older animals. Levels of As that can alter gene expression are transmitted to neonatal mice in lactational milk produced by mothers drinking water containing As, raising concerns about breastfeeding in countries having As-contaminated groundwater. Reduction of BER transcript levels in 24-week-old mice exposed to As for 2 weeks suggests As may potentiate sensitivity to itself in older animals.

Effects of Saikokaryukotsuboreito on Spermatogenesis and Fertility in Aging Male Mice.

PubMed

Zang, Zhi-Jun; Ji, Su-Yun; Zhang, Ya-Nan; Gao, Yong; Zhang, Bin

2016-04-05

Aspermia caused by exogenous testosterone limit its usage in late-onset hypogonadism (LOH) patients desiring fertility. Saikokaryukotsuboreito (SKRBT) is reported to improve serum testosterone and relieve LOH-related symptoms. However, it is unclear whether SKRBT affects fertility. We aimed to examine the effects of SKRBT on spermatogenesis and fertility in aging male mice. Thirty aging male mice were randomly assigned to three groups. Mice were orally administered with phosphate-buffer solution or SKRBT (300 mg/kg, daily) or received testosterone by subcutaneous injections (10 mg/kg, every 3 days). Thirty days later, each male mouse was mated with two female mice. All animals were sacrificed at the end of 90 days. Intratesticular testosterone (ITT) levels, quality of sperm, expression of synaptonemal complex protein 3 (SYCP3), and fertility were assayed. In the SKRBT-treated group, ITT, quality of sperm, and expression of SYCP3 were all improved compared with the control group (ITT: 85.50 ± 12.31 ng/g vs. 74.10 ± 11.45 ng/g, P = 0.027; sperm number: [14.94 ± 4.63] × 106 cells/ml vs. [8.79 ± 4.38] × 106 cells/ml, P = 0.002; sperm motility: 43.16 ± 9.93% vs. 33.51 ± 6.98%, P = 0.015; the number of SYCP3-positive cells/tubule: 77.50 ± 11.01 ng/ml vs. 49.30 ± 8.73 ng/ml, P < 0.001; the expression of SYCP3 protein: 1.23 ± 0.09 vs. 0.84 ± 0.10, P < 0.001), but fertility was not significantly changed (P > 0.05, respectively). In the testosterone-treated group, ITT, quality of sperm, and expression of SYCP3 were markedly lower than the control group (ITT: 59.00 ± 8.67, P = 0.005; sperm number: [4.34 ± 2.45] × 106 cells/ml, P = 0.018; sperm motility: 19.53 ± 7.69%, P = 0.001; the number of SYCP3-positive cells/tubule: 30.00 ± 11.28, P < 0.001; the percentage of SYCP3-positive tubules/section 71.98 ± 8.88%, P = 0.001; the expression of SYCP3 protein: 0.71 ± 0.09, P < 0.001), and fertility was also suppressed (P < 0.05, respectively). SKRBT had no adverse

Sclerostin Immunoreactivity Increases in Cortical Bone Osteocytes and Decreases in Articular Cartilage Chondrocytes in Aging Mice.

PubMed

Thompson, Michelle L; Jimenez-Andrade, Juan Miguel; Mantyh, Patrick W

2016-03-01

Sclerostin is a 24-kDa secreted glycoprotein that has been identified as a negative modulator of new bone formation and may play a major role in age-related decline in skeletal function. Although serum levels of sclerostin markedly increase with age, relatively little is known about whether cells in the skeleton change their expression of sclerostin with aging. Using immunohistochemistry and confocal microscopy, we explored sclerostin immunoreactivity (sclerostin-IR) in the femurs of 4-, 9-, and 24-month-old adult C3H/HeJ male mice. In the femur, the only two cell types that expressed detectable levels of sclerostin-IR were bone osteocytes and articular cartilage chondrocytes. At three different sites along the diaphysis of the femur, only a subset of osteocytes expressed sclerostin-IR and the percentage of osteocytes that expressed sclerostin-IR increased from approximately 36% to 48% in 4- vs. 24-month-old mice. In marked contrast, in the same femurs, there were ~40% fewer hypertrophic chondrocytes of articular cartilage that expressed sclerostin-IR when comparing 24- vs. 4-month-old mice. Understanding the mechanism(s) that drive these divergent changes in sclerostin-IR may provide insight into understanding and treating the age-related decline of the skeleton. © 2016 The Histochemical Society.

Inhibition of xanthine oxidase reduces oxidative stress and improves skeletal muscle function in response to electrically stimulated isometric contractions in aged mice

PubMed Central

Ryan, Michael J.; Jackson, Janna R.; Hao, Yanlei; Leonard, Stephen S.; Alway, Stephen E.

2012-01-01

Oxidative stress is a putative factor responsible for reducing function and increasing apoptotic signaling in skeletal muscle with aging. This study examined the contribution and functional significance of the xanthine oxidase enzyme as a potential source of oxidant production in aged skeletal muscle during repetitive in situ electrically stimulated isometric contractions. Xanthine oxidase activity was inhibited in young adult and aged mice via a subcutaneously placed time release (2.5 mg/day) allopurinol pellet, 7 days prior to the start of in situ electrically stimulated isometric contractions. Gastrocnemius muscles were electrically activated with 20 maximal contractions for three consecutive days. Xanthine oxidase activity was 65% greater in the gastrocnemius muscle of aged mice compared to young mice. Xanthine oxidase activity also increased after in situ electrically stimulated isometric contractions in muscles from both young (33%) and aged (28%) mice, relative to contralateral non-contracted muscles. Allopurinol attenuated the exercise-induced increase in oxidative stress, but it did not affect the elevated basal levels of oxidative stress that was associated with aging. In addition, inhibition of xanthine oxidase activity decreased caspase 3 activity, but it had no effect on other markers of mitochondrial associated apoptosis. Our results show that compared to control conditions, suppression of xanthine oxidase activity by allopurinol reduced xanthine oxidase activity, H2O2 levels, lipid peroxidation and caspase-3 activity, prevented the in situ electrically stimulated isometric contraction-induced loss of glutathione, prevented the increase of catalase and copper-zinc superoxide dismutase activities, and increased maximal isometric force in the plantar flexor muscles of aged mice after repetitive electrically evoked contractions. PMID:21530649

The comparative immunology of wild and laboratory mice, Mus musculus domesticus

PubMed Central

Abolins, Stephen; King, Elizabeth C.; Lazarou, Luke; Weldon, Laura; Hughes, Louise; Drescher, Paul; Raynes, John G.; Hafalla, Julius C. R.; Viney, Mark E.; Riley, Eleanor M.

2017-01-01

The laboratory mouse is the workhorse of immunology, used as a model of mammalian immune function, but how well immune responses of laboratory mice reflect those of free-living animals is unknown. Here we comprehensively characterize serological, cellular and functional immune parameters of wild mice and compare them with laboratory mice, finding that wild mouse cellular immune systems are, comparatively, in a highly activated (primed) state. Associations between immune parameters and infection suggest that high level pathogen exposure drives this activation. Moreover, wild mice have a population of highly activated myeloid cells not present in laboratory mice. By contrast, in vitro cytokine responses to pathogen-associated ligands are generally lower in cells from wild mice, probably reflecting the importance of maintaining immune homeostasis in the face of intense antigenic challenge in the wild. These data provide a comprehensive basis for validating (or not) laboratory mice as a useful and relevant immunological model system. PMID:28466840

Age-dependent differences in nicotine reward and withdrawal in female mice.

PubMed

Kota, D; Martin, B R; Damaj, M I

2008-06-01

Adolescent smoking is an increasing epidemic in the US. Research has shown that the commencement of smoking at a young age increases addiction and decreases the probability of successful cessation; however, limited work has focused on nicotine dependence in the female. The goal of the present study was to identify the biological and behavioral factors that may contribute to nicotine's increased abuse liability in female adolescents using animal models of nicotine dependence. Early adolescent (PND 28) and adult (PND 70) female mice were compared in various aspects of nicotine dependence using reward and withdrawal models following sub-chronic nicotine exposure. Furthermore, in vivo acute sensitivity and tolerance to nicotine were examined. In the conditioned place preference model, adolescents demonstrated a significant preference at 0.5 mg/kg nicotine, an inactive dose in adults. Adults found higher doses (0.7 and 1.0 mg/kg) of nicotine to elicit rewarding effects. Furthermore, adolescents displayed increased physical, but not affective, withdrawal signs in three models. Upon acute exposure to nicotine, adolescent mice showed increased sensitivity in an analgesic measure as well as hypothermia. After chronic nicotine exposure, both adults and adolescents displayed tolerance to nicotine with adolescents having a lower degree of tolerance to changes in body temperature. These data indicate that differences in nicotine's rewarding and aversive effects may contribute to variations in certain components of nicotine dependence between adult and adolescent female mice. Furthermore, this implies that smoking cessation therapies may not be equally effective across all ages.

In vivo antioxidant activity of total flavonoids from indocalamus leaves in aging mice caused by D-galactose.

PubMed

Jin, Sheng-lang; Yin, Yong-guang

2012-10-01

The aim of this thesis is to explore antioxidant activity of total flavonoids extracted from indocalamus leaves. Aging mice model was established by D-galactose induction. Three groups of mice were treated with total flavonoids extracted from indocalamus leaves at doses of 20, 40 and 80 mg/kg d bw respectively. The antioxidant status in the aging mice was measured by determining the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and total anti-oxidant capability (T-AOC) in the serum and liver and malondialdehyde (MDA) content in the serum, liver and brain. Compared with control group, extracts of indocalamus leaves significantly enhanced activities of SOD, GSH-Px, CAT in the serum and liver, and decreased MDA content in the serum, liver and brain at the tested doses. Total flavonoids extracted from indocalamus leaves demonstrated the potent antioxidant activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

Activity of antioxidant enzymes and concentration of lipid peroxidation products in selected tissues of mice of different ages, both healthy and melanoma-bearing.

PubMed

Woźniak, A; Drewa, G; Woźniak, B; Schachtschabel, D O

2004-06-01

The activity of antioxidant enzymes and the concentration of the lipid peroxidation product malondialdehyde (MDA) as indicator of oxidative damage were determined in selected tissues of healthy mice and transplanted B16 melanoma-bearing mice with increasing age. A total of 60 male mice were divided into 6 groups. Groups 1, 2 and 3 consisted of tumor-free, healthy mice aged 1, 9 and 16 months, respectively (average life span: 2 years). Groups 4, 5 and 6 consisted of mice of the same age as the healthy mice, but given intraperitoneally 10(6) cells of B16 melanoma for 2 weeks. An increase in the concentration of MDA was found in all the studied tissues (brain, liver, lungs, erythrocytes) and blood plasma of 16-month old healthy mice compared with the younger ones. The activity of superoxide dismutase (SOD) and catalase (CAT) was elevated in the brain and the activity of CAT and glutathione peroxidase (GPx) in the liver of aged healthy mice. The transplantation of melanoma caused an increase of the concentration of MDA and of the activity of all studied enzymes in all tissues. This elevation was most pronounced in the youngest mice group 4 and was higher than in the oldest healthy group 3. Thus, these early changes of the "(anti-)oxidative status" in the investigated tissues caused by the tumor development have similarities with age-associated alterations of healthy mice, especially in regard to MDA in all tissues or SOD and CAT in brain.

Aging aggravates ischemic stroke-induced brain damage in mice with chronic peripheral infection.

PubMed

Dhungana, Hiramani; Malm, Tarja; Denes, Adam; Valonen, Piia; Wojciechowski, Sara; Magga, Johanna; Savchenko, Ekaterina; Humphreys, Neil; Grencis, Richard; Rothwell, Nancy; Koistinaho, Jari

2013-10-01

Ischemic stroke is confounded by conditions such as atherosclerosis, diabetes, and infection, all of which alter peripheral inflammatory processes with concomitant impact on stroke outcome. The majority of the stroke patients are elderly, but the impact of interactions between aging and inflammation on stroke remains unknown. We thus investigated the influence of age on the outcome of stroke in animals predisposed to systemic chronic infection. Th1-polarized chronic systemic infection was induced in 18-22 month and 4-month-old C57BL/6j mice by administration of Trichuris muris (gut parasite). One month after infection, mice underwent permanent middle cerebral artery occlusion and infarct size, brain gliosis, and brain and plasma cytokine profiles were analyzed. Chronic infection increased the infarct size in aged but not in young mice at 24 h. Aged, ischemic mice showed altered plasma and brain cytokine responses, while the lesion size correlated with plasma prestroke levels of RANTES. Moreover, the old, infected mice exhibited significantly increased neutrophil recruitment and upregulation of both plasma interleukin-17α and tumor necrosis factor-α levels. Neither age nor infection status alone or in combination altered the ischemia-induced brain microgliosis. Our results show that chronic peripheral infection in aged animals renders the brain more vulnerable to ischemic insults, possibly by increasing the invasion of neutrophils and altering the inflammation status in the blood and brain. Understanding the interactions between age and infections is crucial for developing a better therapeutic regimen for ischemic stroke and when modeling it as a disease of the elderly. © 2013 The Anatomical Society and John Wiley & Sons Ltd.

Synergistic effect of aged garlic extract and naltrexone on improving immune responses to experimentally induced fibrosarcoma tumor in BALB/c mice

PubMed Central

Ebrahimpour, Soheil; Tabari, Mohaddeseh Abouhosseini; Youssefi, Mohammad Reza; Aghajanzadeh, Hamid; Behzadi, Manijeh Yousefi

2013-01-01

Background: Garlic, a medicinal plant, and Naltrexone (NTX), an opioid receptor antagonist, both have immunomodulatory and antitumor effects. Current study was designed to evaluate synergistic antitumor effects of aged garlic extract (AGE) and NTX. Materials and Methods: WEHI-164 fibrosarcoma cells were implanted subcutaneously on day 0 into right flank of 80 BALB/c mice at age of 8 weeks. Mice were randomly categorized in four separate groups: The first group received AGE (100 mg/kg, i.p.), the second group received NTX (0.5 mg/kg, i.p.), the third group received both of them, and the fourth group received phosphate buffered saline as control group. Treatments were administered three times per week. Tumor growth was measured and morbidity was recorded. Subpopulations of CD4+/CD8+ T cells were determined using flowcytometery. WEHI-164 cell specific cytotoxicity of splenocytes and in vitro production of interferon-gamma (IFN-γ) and interleukin-4 (IL-4) cytokines were measured. All statistical analyses were conducted with SPSS 16 software and P < 0.05 was considered to be statistically significant. Results: The mice who received AGE+NTX had significantly longer survival time compared with the mice treated with AGE or NTX alone. An enhanced inhibitory effect on tumor growth was seen in combination therapy group. The CD4+/CD8+ ratio and in vitro IFN-γ production of splenocytes were significantly increased in AGE+NTX and NTX groups. WEHI-164 specific cytotoxicity of splenocytes was also significantly increased at 25:1 E:T ratio in AGE+NTX treated mice. Coadministration of AGE with NTX resulted in improvement of immune responses against experimentally implanted fibrosarcoma tumors in BALB/c mice. Conclusions: AGE showed synergistic effects with NTX on inhibition of tumor growth and increment of survival times. PMID:23901215

Aniracetam restores the effects of amyloid-beta protein or ageing on membrane fluidity and intracellular calcium concentration in mice synaptosomes.

PubMed

Li, Y; Wang, J-J; Cai, J-X

2007-01-01

In the present study, we observed the in vitro effect of aniracetam on membrane fluidity and free calcium concentrations ([Ca(2+)]i) of frontal cortical (FC) and hippocampal (HP) synaptosomes of aged mice and young mice treated with amyloid-beta protein (Abeta) Membrane fluidity was measured by using fluorescence anisotropy of the lipophilic probe, 1,6-diphenyl-1,3,5-hexatriene (DPH). [Ca(2+)]i was measured by using Fura 2-AM fluorescent spectrophotometry. We found that membrane fluidity of the FC and HP synaptosomes was decreased in 14 months old mice compared with that in 3 months old mice. Similarly, Abeta25-35 (1 microM) decreased the membrane fluidity in 3 months old mice. These effects of ageing and Abeta25-35 on membrane fluidity were restored by aniracetam in a concentration-dependent manner. Furthermore, Abeta25-35 (1 microM) largely increased [Ca(2+)]i in FC and HP synaptosomes in 3 months old mice, but this effect on HP synaptosomes was effectively reversed by aniracetam (1-4 mM). The present findings suggest that aniracetam restores age- and Abeta-induced alterations in membrane fluidity or Abeta-induced increase in [Ca(2+)]i, demonstrating a possible beneficial role of aniracetam in the clinic treatment for senile dementia or Alzheimer's disease.

Ischemic postconditioning confers cardioprotection and prevents reduction of Trx-1 in young mice, but not in middle-aged and old mice.

PubMed

Perez, Virginia; D Annunzio, Verónica; Mazo, Tamara; Marchini, Timoteo; Caceres, Lourdes; Evelson, Pablo; Gelpi, Ricardo J

2016-04-01

Thioredoxin-1 (Trx-1) is part of an antioxidant system that maintains the cell redox homeostasis but their role on ischemic postconditioning (PostC) is unknown. The aim of this work was to determine whether Trx-1 participates in the cardioprotective mechanism of PostC in young, middle-aged, and old mice. Male FVB young (Y: 3 month-old), middle-aged (MA: 12 month-old), and old (O: 20 month-old) mice were used. Langendorff-perfused hearts were subjected to 30 min of ischemia and 120 min of reperfusion (I/R group). After ischemia, we performed 6 cycles of R/I (10 s each) followed by 120 min of reperfusion (PostC group). We measured the infarct size (triphenyltetrazolium); Trx-1, total and phosphorylated Akt, and GSK3β expression (Western blot); and the GSH/GSSG ratio (HPLC). PostC reduced the infarct size in young mice (I/R-Y: 52.3 ± 2.4 vs. PostC-Y: 40.0 ± 1.9, p < 0.05), but this protection was abolished in the middle-aged and old mice groups. Trx-1 expression decreased after I/R, and the PostC prevented the protein degradation in young animals (I/R-Y: 1.05 ± 0.1 vs. PostC-Y: 0.52 ± .0.07, p < 0.05). These changes were accompanied by an improvement in the GSH/GSSG ratio (I/R-Y: 1.25 ± 0.30 vs. PostC-Y: 7.10 ± 2.10, p < 0.05). However, no changes were observed in the middle-aged and old groups. Cytosolic Akt and GSK3β phosphorylation increased in the PostC compared with the I/R group only in young animals. Our results suggest that PostC prevents Trx-1 degradation, decreasing oxidative stress and allowing the activation of Akt and GSK3β to exert its cardioprotective effect. This protection mechanism is not activated in middle-aged and old animals.

A multi-ingredient dietary supplement abolishes large-scale brain cell loss, improves sensory function, and prevents neuronal atrophy in aging mice.

PubMed

Lemon, J A; Aksenov, V; Samigullina, R; Aksenov, S; Rodgers, W H; Rollo, C D; Boreham, D R

2016-06-01

Transgenic growth hormone mice (TGM) are a recognized model of accelerated aging with characteristics including chronic oxidative stress, reduced longevity, mitochondrial dysfunction, insulin resistance, muscle wasting, and elevated inflammatory processes. Growth hormone/IGF-1 activate the Target of Rapamycin known to promote aging. TGM particularly express severe cognitive decline. We previously reported that a multi-ingredient dietary supplement (MDS) designed to offset five mechanisms associated with aging extended longevity, ameliorated cognitive deterioration and significantly reduced age-related physical deterioration in both normal mice and TGM. Here we report that TGM lose more than 50% of cells in midbrain regions, including the cerebellum and olfactory bulb. This is comparable to severe Alzheimer's disease and likely explains their striking age-related cognitive impairment. We also demonstrate that the MDS completely abrogates this severe brain cell loss, reverses cognitive decline and augments sensory and motor function in aged mice. Additionally, histological examination of retinal structure revealed markers consistent with higher numbers of photoreceptor cells in aging and supplemented mice. We know of no other treatment with such efficacy, highlighting the potential for prevention or amelioration of human neuropathologies that are similarly associated with oxidative stress, inflammation and cellular dysfunction. Environ. Mol. Mutagen. 57:382-404, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Expression of Human Complement Factor H Prevents Age-Related Macular Degeneration–Like Retina Damage and Kidney Abnormalities in Aged Cfh Knockout Mice

PubMed Central

Ding, Jin-Dong; Kelly, Una; Landowski, Michael; Toomey, Christopher B.; Groelle, Marybeth; Miller, Chelsey; Smith, Stephanie G.; Klingeborn, Mikael; Singhapricha, Terry; Jiang, Haixiang; Frank, Michael M.; Bowes Rickman, Catherine

2016-01-01

Complement factor H (CFH) is an important regulatory protein in the alternative pathway of the complement system, and CFH polymorphisms increase the genetic risk of age-related macular degeneration dramatically. These same human CFH variants have also been associated with dense deposit disease. To mechanistically study the function of CFH in the pathogenesis of these diseases, we created transgenic mouse lines using human CFH bacterial artificial chromosomes expressing full-length human CFH variants and crossed these to Cfh knockout (Cfh−/−) mice. Human CFH protein inhibited cleavage of mouse complement component 3 and factor B in plasma and in retinal pigment epithelium/choroid/sclera, establishing that human CFH regulates activation of the mouse alternative pathway. One of the mouse lines, which express relatively higher levels of CFH, demonstrated functional and structural protection of the retina owing to the Cfh deletion. Impaired visual function, detected as a deficit in the scotopic electroretinographic response, was improved in this transgenic mouse line compared with Cfh−/− mice, and transgenics had a thicker outer nuclear layer and less sub–retinal pigment epithelium deposit accumulation. In addition, expression of human CFH also completely protected the mice from developing kidney abnormalities associated with loss of CFH. These humanized CFH mice present a valuable model for study of the molecular mechanisms of age-related macular degeneration and dense deposit disease and for testing therapeutic targets. PMID:25447048

Cryo-survival, fertilization and early embryonic development of vitrified oocytes derived from mice of different reproductive age

PubMed Central

Yan, Jie; Suzuki, Joao; Yu, Xiaomin; Kan, Frederick W. K.

2010-01-01

Purpose To evaluate the effect of female reproductive age on oocyte cryo-survival, fertilization and the subsequent embryonic development following vitrification using the mouse model in order to address the question of how maternal reproductive age is related to fertility preservation. Methods Oocytes were collected from mice of different reproductive age: (1) 8–10 weeks, (2) 16–20 weeks, (3) 32–36 weeks, and (4) 44–48 weeks. Following vitrification and warming, the oocytes in each group were assessed for cryo-survival, fertilization and embryonic development as well as for the quality of blastocysts. Fresh oocytes without undergoing vitrification were used in each age group as controls. Results The mean number of oocytes retrieved following superovulation was found to reduce significantly (P < 0.05) in mice from 32–36 weeks of age (18.1 ± 8.5) compared with 8–10 weeks of age (26.8 ± 9.8) and 16–20 weeks of age (23.9 ± 4.2) respectively. The cryo-survival rate of oocytes was reduced significantly (P < 0.05) in mice of 44–48 weeks of age (90.4% ± 7.9) compared with the other 3 groups (98.8% ± 2.1, 98.0% ± 3.3 and 98.5% ± 2.2, respectively). The cleavage rate of vitrified oocytes declined significantly following the increase in maternal age in mice of 32–36 weeks of age (69.7% ± 20.8) forward (63.6% ± 9.2). However, no significant difference in the cleavage rate was found among the control groups of different maternal ages. The rate of embryo development to the blastocyst stage in the vitrified oocytes also significantly declined following the increase in maternal age (71.8% ± 8.8, 66.4% ± 10.7, 64.2% ± 17.4 and 4.1% ± 8.3 respectively). There were no such differences in the rates of embryo development to the blastocyst stage among the control groups following the increase in maternal age (75.9% ± 12.2, 79.5% ± 28.9, 70.2% ± 17.4 and 69.3% ± 19

Hypervitaminosis D and premature aging: lessons learned from Fgf23 and Klotho mutant mice.

PubMed

Razzaque, Mohammed S; Lanske, Beate

2006-07-01

The essential role of low levels of vitamin D during aging is well documented. However, possible effects of high levels of vitamin D on the aging process are not yet clear. Recent in vivo genetic-manipulation studies have shown increased serum level of vitamin D and altered mineral-ion homeostasis in mice that lack either fibroblast growth factor 23 (Fgf23) or klotho (Kl) genes. These mice develop identical phenotypes consistent with premature aging. Elimination or reduction of vitamin-D activity from Fgf23 and Kl mutant mice, either by dietary restriction or genetic manipulation could rescue premature aging-like features and ectopic calcifications, resulting in prolonged survival of both mutants. Such in vivo experimental studies indicated that excessive vitamin-D activity and altered mineral-ion homeostasis could accelerate the aging process.

Comparative Endocrinology of Aging and Longevity Regulation

PubMed Central

Allard, John B.; Duan, Cunming

2011-01-01

Hormones regulate growth, development, metabolism, and other complex processes in multicellular animals. For many years it has been suggested that hormones may also influence the rate of the aging process. Aging is a multifactorial process that causes biological systems to break down and cease to function in adult organisms as time passes, eventually leading to death. The exact underlying causes of the aging process remain a topic for debate, and clues that may shed light on these causes are eagerly sought after. In the last two decades, gene mutations that result in delayed aging and extended longevity have been discovered, and many of the affected genes have been components of endocrine signaling pathways. In this review we summarize the current knowledge on the roles of endocrine signaling in the regulation of aging and longevity in various animals. We begin by discussing the notion that conserved systems, including endocrine signaling pathways, “regulate” the aging process. Findings from the major model organisms: worms, flies, and rodents, are then outlined. Unique lessons from studies of non-traditional models: bees, salmon, and naked mole rats, are also discussed. Finally, we summarize the endocrinology of aging in humans, including changes in hormone levels with age, and the involvement of hormones in aging-related diseases. The most well studied and widely conserved endocrine pathway that affects aging is the insulin/insulin-like growth factor system. Mutations in genes of this pathway increase the lifespan of worms, flies, and mice. Population genetic evidence also suggests this pathway’s involvement in human aging. Other hormones including steroids have been linked to aging only in a subset of the models studied. Because of the value of comparative studies, it is suggested that the aging field could benefit from adoption of additional model organisms. PMID:22654825

Alpha-ketoglutarate stabilizes redox homeostasis and improves arterial elasticity in aged mice.

PubMed

Niemiec, T; Sikorska, J; Harrison, A; Szmidt, M; Sawosz, E; Wirth-Dzieciolowska, E; Wilczak, J; Pierzynowski, S

2011-02-01

The objective of this study was to evaluate the effect of α-ketoglutarate on redox state parameters and arterial elasticity in elderly mice. Mice in the control group were fed with standard diet, while the experimental animals received the diet supplemented either with calcium (Ca-AKG) or sodium salt of α-ketoglutarate (Na-AKG). The experimental animals were divided into 4 groups with 10 individuals in each: control I (12 months old), control II (2 months old), experimental group I fed with Ca-AKG (12 months old) and experimental group II fed with Na-AKG (12 months old). Mice treated with Ca-AKG as well as the control II animals demonstrated significantly higher level of total antioxidant status (TAS), comparing to the control I animals and those treated with Ca-AKG. Thiobarbituric acid reactive substances (TBARS) level in blood plasma was found significantly lower in young and Ca-AKG treated mice. TBARS liver concentration was significantly different in each examined group. The study also demonstrates the decrease in TBARS level in Ca-AKG treated animals. Treatment with Na-AKG significantly increased glutathione peroxidase activity and decreased the activity of superoxide dismutase. The presented results suggest that Ca-AKG protects the organism against the free radicals related elderly processes. The study presents also the effect of Ca-AKG treatment on arterial elastic characteristics in elderly mice. The beneficial effect of Ca-AKG on ageing organisms was confirmed via redox state stabilization and blood vessel elasticity improvement.

Wound healing delays in α-Klotho-deficient mice that have skin appearance similar to that in aged humans - Study of delayed wound healing mechanism.

PubMed

Yamauchi, Makoto; Hirohashi, Yoshihiko; Torigoe, Toshihiko; Matsumoto, Yoshitaka; Yamashita, Ken; Kayama, Musashi; Sato, Noriyuki; Yotsuyanagi, Takatoshi

2016-05-13

Skin atrophy and delayed wound healing are observed in aged humans; however, the molecular mechanism are still elusive. The aim of this study was to analyze the molecular mechanisms of delayed wound healing by aging using α-Klotho-deficient (kl/kl) mice, which have phenotypes similar to those of aged humans. The kl/kl mice showed delayed wound healing and impaired granulation formation compared with those in wild-type (WT) mice. The skin graft experiments revealed that delayed wound healing depends on humoral factors, but not on kl/kl skin tissue. The mRNA expression levels of cytokines related to acute inflammation including IL-1β, IL-6 and TNF-α were higher in wound lesions of kl/kl mice compared with the levels in WT mice by RT-PCR analysis. LPS-induced TNF-α production model using spleen cells revealed that TNF-α production was significantly increased in the presence of FGF23. Thus, higher levels of FGF23 in kl/kl mouse may have a role to increase TNF-α production in would lesion independently of α-Klotho protein, and impair granulation formation and delay wound healing. Copyright © 2016 Elsevier Inc. All rights reserved.

Age-dependent postoperative cognitive impairment and Alzheimer-related neuropathology in mice

NASA Astrophysics Data System (ADS)

Xu, Zhipeng; Dong, Yuanlin; Wang, Hui; Culley, Deborah J.; Marcantonio, Edward R.; Crosby, Gregory; Tanzi, Rudolph E.; Zhang, Yiying; Xie, Zhongcong

2014-01-01

Post-operative cognitive dysfunction (POCD) is associated with increased cost of care, morbidity, and mortality. However, its pathogenesis remains largely to be determined. Specifically, it is unknown why elderly patients are more likely to develop POCD and whether POCD is dependent on general anesthesia. We therefore set out to investigate the effects of peripheral surgery on the cognition and Alzheimer-related neuropathology in mice with different ages. Abdominal surgery under local anesthesia was established in the mice. The surgery induced post-operative elevation in brain β-amyloid (Aβ) levels and cognitive impairment in the 18 month-old wild-type and 9 month-old Alzheimer's disease transgenic mice, but not the 9 month-old wild-type mice. The Aβ accumulation likely resulted from elevation of beta-site amyloid precursor protein cleaving enzyme and phosphorylated eukaryotic translation initiation factor 2α. γ-Secretase inhibitor compound E ameliorated the surgery-induced brain Aβ accumulation and cognitive impairment in the 18 month-old mice. These data suggested that the peripheral surgery was able to induce cognitive impairment independent of general anesthesia, and that the combination of peripheral surgery with aging- or Alzheimer gene mutation-associated Aβ accumulation was needed for the POCD to occur. These findings would likely promote more research to investigate the pathogenesis of POCD.

Altered temporal patterns of anxiety in aged and amyloid precursor protein (APP) transgenic mice.

PubMed

Bedrosian, Tracy A; Herring, Kamillya L; Weil, Zachary M; Nelson, Randy J

2011-07-12

Both normal aging and dementia are associated with dysregulation of the biological clock, which contributes to disrupted circadian organization of physiology and behavior. Diminished circadian organization in conjunction with the loss of cholinergic input to the cortex likely contributes to impaired cognition and behavior. One especially notable and relatively common circadian disturbance among the aged is "sundowning syndrome," which is characterized by exacerbated anxiety, agitation, locomotor activity, and delirium during the hours before bedtime. Sundowning has been reported in both dementia patients and cognitively intact elderly individuals living in institutions; however, little is known about temporal patterns in anxiety and agitation, and the neurobiological basis of these rhythms remains unspecified. In the present study, we explored the diurnal pattern of anxiety-like behavior in aged and amyloid precursor protein (APP) transgenic mice. We then attempted to treat the observed behavioral disturbances in the aged mice using chronic nightly melatonin treatment. Finally, we tested the hypothesis that time-of-day differences in acetylcholinesterase and choline acetyltransferase expression and general neuronal activation (i.e., c-Fos expression) coincide with the behavioral symptoms. Our results show a temporal pattern of anxiety-like behavior that emerges in elderly mice. This behavioral pattern coincides with elevated locomotor activity relative to adult mice near the end of the dark phase, and with time-dependent changes in basal forebrain acetylcholinesterase expression. Transgenic APP mice show a similar behavioral phenomenon that is not observed among age-matched wild-type mice. These results may have useful applications to the study and treatment of age- and dementia-related circadian behavioral disturbances, namely, sundowning syndrome.

Aged mice receiving caffeine since adulthood show distinct patterns of anxiety-related behavior.

PubMed

Botton, Paulo Henrique S; Pochmann, Daniela; Rocha, Andreia S; Nunes, Fernanda; Almeida, Amanda S; Marques, Daniela M; Porciúncula, Lisiane O

2017-03-01

Caffeine is the psychostimulant most consumed worldwide. Anxiogenic effects of caffeine have been described in adult animals with controversial findings about its anxiogenic potential. Besides, the effects of caffeine on anxiety with aging are still poorly known. In this study, adult mice (6months old) started to receive caffeine (0.3 and 1.0mg/mL, drinking water) during 12-14months only in the light cycle and at weekdays. The open field (OF) and elevated plus maze (EPM) testing were used to determine the effects of caffeine on anxiety-related behavior in adult and aged mice (18-20months old). Because aging alters synaptic proteins, we also evaluated SNAP-25 (as a nerve terminals marker), GFAP (as an astrocyte marker) and adenosine A 1 and A 2A receptors levels in the cortex. According to the OF analysis, caffeine did not change both hypolocomotion and anxiety with aging. However, aged mice showed less anxiety behavior in the EPM, but after receiving caffeine (0.3mg/mL) during adulthood they were anxious as adult mice. While SNAP-25 and adenosine A 2A receptors increased with aging, both GFAP and adenosine A 1 receptors were not affected. Caffeine at moderate dose prevented the age-related increase of the SNAP-25, with no effect on adenosine A 2A receptors. The absence of effect for the highest dose suggests that tolerance to caffeine may have developed over time. Aged mice showed high responsiveness to the OF, being difficult to achieve any effect of caffeine. On the other hand this substance sustained the adult anxious behavior over time in a less stressful paradigm, and this effect was coincident with changes in the SNAP-25, suggesting the involvement of this synaptic protein in the ability of caffeine to preserve changes related to emotionality with aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Restricted diet delays accelerated ageing and genomic stress in DNA-repair-deficient mice.

PubMed

Vermeij, W P; Dollé, M E T; Reiling, E; Jaarsma, D; Payan-Gomez, C; Bombardieri, C R; Wu, H; Roks, A J M; Botter, S M; van der Eerden, B C; Youssef, S A; Kuiper, R V; Nagarajah, B; van Oostrom, C T; Brandt, R M C; Barnhoorn, S; Imholz, S; Pennings, J L A; de Bruin, A; Gyenis, Á; Pothof, J; Vijg, J; van Steeg, H; Hoeijmakers, J H J

2016-09-15

Mice deficient in the DNA excision-repair gene Ercc1 (Ercc1 ∆/- ) show numerous accelerated ageing features that limit their lifespan to 4-6 months. They also exhibit a 'survival response', which suppresses growth and enhances cellular maintenance. Such a response resembles the anti-ageing response induced by dietary restriction (also known as caloric restriction). Here we report that a dietary restriction of 30% tripled the median and maximal remaining lifespans of these progeroid mice, strongly retarding numerous aspects of accelerated ageing. Mice undergoing dietary restriction retained 50% more neurons and maintained full motor function far beyond the lifespan of mice fed ad libitum. Other DNA-repair-deficient, progeroid Xpg -/- (also known as Ercc5 -/- ) mice, a model of Cockayne syndrome, responded similarly. The dietary restriction response in Ercc1 ∆/- mice closely resembled the effects of dietary restriction in wild-type animals. Notably, liver tissue from Ercc1 ∆/- mice fed ad libitum showed preferential extinction of the expression of long genes, a phenomenon we also observed in several tissues ageing normally. This is consistent with the accumulation of stochastic, transcription-blocking lesions that affect long genes more than short ones. Dietary restriction largely prevented this declining transcriptional output and reduced the number of γH2AX DNA damage foci, indicating that dietary restriction preserves genome function by alleviating DNA damage. Our findings establish the Ercc1 ∆/- mouse as a powerful model organism for health-sustaining interventions, reveal potential for reducing endogenous DNA damage, facilitate a better understanding of the molecular mechanism of dietary restriction and suggest a role for counterintuitive dietary-restriction-like therapy for human progeroid genome instability syndromes and possibly neurodegeneration in general.

Characterization of AD-like phenotype in aged APPSwe/PS1dE9 mice.

PubMed

Huang, Huang; Nie, Sipei; Cao, Min; Marshall, Charles; Gao, Junying; Xiao, Na; Hu, Gang; Xiao, Ming

2016-08-01

Transgenic APPSwe/PS1dE9 (APP/PS1) mice that overproduce amyloid beta (Aβ) are extensively used in the studies of pathogenesis and experimental therapeutics and new drug screening for Alzheimer's disease (AD). However, most of the current literature uses young or adult APP/PS1 mice. In order to provide a broader view of AD-like phenotype of this animal model, in this study, we systematically analyzed behavioral and pathological profiles of 24-month-old male APP/PS1 mice. Aged APP/PS1 mice had reference memory deficits as well as anxiety, hyperactivity, and social interaction impairment. Consistently, there was obvious deposition of amyloid plaques in the dorsal hippocampus with decreased expression of insulin-degrading enzyme, a proteolytic enzyme responsible for degradation of intracellular Aβ. Furthermore, decreases in hippocampal volume, neuronal number and synaptophysin expression, and astrocyte atrophy were also observed in aged APP/PS1 mice. This finding suggests that aged APP/PS1 mice can well replicate cognitive and noncognitive behavioral abnormalities, hippocampal atrophy, and neuronal and astrocyte degeneration in AD patients, to enable more objective and refined preclinical evaluation of therapeutic drugs and strategies for AD treatment.

Curcumin attenuates surgery-induced cognitive dysfunction in aged mice.

PubMed

Wu, Xiang; Chen, Huixin; Huang, Chunhui; Gu, Xinmei; Wang, Jialing; Xu, Dilin; Yu, Xin; Shuai, Chu; Chen, Liping; Li, Shun; Xu, Yiguo; Gao, Tao; Ye, Mingrui; Su, Wei; Liu, Haixiong; Zhang, Jinrong; Wang, Chuang; Chen, Junping; Wang, Qinwen; Cui, Wei

2017-06-01

Post-operative cognitive dysfunction (POCD) is associated with elderly patients undergoing surgery. However, pharmacological treatments for POCD are limited. In this study, we found that curcumin, an active compound derived from Curcuma longa, ameliorated the cognitive dysfunction following abdominal surgery in aged mice. Further, curcumin prevented surgery-induced anti-oxidant enzyme activity. Curcumin also increased brain-derived neurotrophic factor (BDNF)-positive area and expression of pAkt in the brain, suggesting that curcumin activated BDNF signaling in aged mice. Furthermore, curcumin neutralized cholinergic dysfunction involving choline acetyltransferase expression induced by surgery. These results strongly suggested that curcumin prevented cognitive impairments via multiple targets, possibly by increasing the activity of anti-oxidant enzymes, activation of BDNF signaling, and neutralization of cholinergic dysfunction, concurrently. Based on these novel findings, curcumin might be a potential agent in POCD prophylaxis and treatment.

Reductions in expression of growth regulating genes in skeletal muscle with age in wild type and myostatin null mice.

PubMed

Jones, Jennifer C; Kroscher, Kellie A; Dilger, Anna C

2014-03-28

Genes that decline in expression with age and are thought to coordinate growth cessation have been identified in various organs, but their expression in skeletal muscle is unknown. Therefore, our objective was to determine expression of these genes (Ezh2, Gpc3, Mdk, Mest, Mycn, Peg3, and Plagl1) in skeletal muscle from birth to maturity. We hypothesized that expression of these genes would decline with age in skeletal muscle but differ between sexes and between wild type and myostatin null mice. Female and male wild type and myostatin null mice (C57BL/6J background) were sacrificed by carbon dioxide asphyxiation followed by decapitation at d -7, 0, 21, 42, and 70 days of age. Whole bodies at d -7, all muscles from both hind limbs at d 0, and bicep femoris muscle from d 21, 42 and 70 were collected. Gene expression was determined by quantitative real-time PCR. In general, expression of these growth-regulating genes was reduced at d 21 compared with day 0 and d -7. Expression of Gpc3, Mest, and Peg3 was further reduced at d 42 and 70 compared with d 21, however the expression of Mycn increased from d 21 to d 42 and 70. Myostatin null mice, as expected, were heavier with increased biceps femoris weight at d 70. However, with respect to sex and genotype, there were few differences in expression. Expression of Ezh2 was increased at d 70 and expression of Mdk was increased at d 21 in myostatin null mice compared with wild type, but no other genotype effects were present. Expression of Mdk was increased in females compared to males at d 70, but no other sex effects were present. Overall, these data suggest the downregulation of these growth-regulating genes with age might play a role in the coordinated cessation of muscle growth similar to organ growth but likely have a limited role in the differences between sexes or genotypes.

Ultraviolet radiation-induced cataract in mice: the effect of age and the potential biochemical mechanism.

PubMed

Zhang, Jie; Yan, Hong; Löfgren, Stefan; Tian, Xiaoli; Lou, Marjorie F

2012-10-19

To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV). Young and old C57BL/6 mice were exposed to broadband UVB+UVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins (PSSGs) were detected by immunoblotting using GSH antibody. Western blot analysis was also done for the expression levels of TTase and Trx. Both age groups developed epithelial and superficial anterior subcapsular cataract at 2 days postexposure. The lens GSH level and G3PD activity were decreased, and PSSGs were elevated in both age groups, but more prominent in the older mice. TTase and Trx activity and protein expression were elevated only in the young mice. Interestingly, lens TTase and Trx in the young mice showed a transient increase, peaking at 2 days after UV exposure and returning to baseline at day 8, corroborated by lens transparency. The lenses of old mice were more susceptible to UV radiation-induced cataract. The upregulated TTase and Trx likely provided oxidation damage repair in the young mice.

Peripheral surgical wounding may induce cognitive impairment through interlukin-6-dependent mechanisms in aged mice.

PubMed

Dong, Yuanlin; Xu, Zhipeng; Huang, Lining; Zhang, Yiying; Xie, Zhongcong

2016-01-01

Post-operative cognitive dysfunction (POCD) is associated with morbidity, mortality and increased cost of medical care. However, the neuropathogenesis and targeted interventions of POCD remain largely to be determined. We have found that the peripheral surgical wounding induces an age-dependent Aβ accumulation, neuroinflammation and cognitive impairment in aged mice. Pro-inflammatory cytokine interlukin-6 (IL-6) has been reported to be associated with cognitive impairment in rodents and humans. However, the role of IL-6 in the neuropathogenesis of POCD is unknown. We therefore employed pharmacological (IL-6 antibody) and genetic (knockout of IL-6) approach to investigate whether IL-6 contributed to the peripheral surgical wounding-induced cognitive impairment in aged mice. Abdominal surgery under local anesthesia (peripheral surgical wounding) was established in 18-month-old wild-type and IL-6 knockout mice ( n = 6 to 10 in each group). Brain level of IL-6 and cognitive function in the mice were determined by western blot, ELISA at the end of procedure, and Fear Conditioning System at 7 days after the procedure. The peripheral surgical wounding increased the level of IL-6 in the hippocampus of aged wild-type, but not IL-6 knockout mice. IL-6 antibody ameliorated the peripheral surgical wounding-induced cognitive impairment in the aged wild-type mice. Finally, the peripheral surgical wounding did not induce cognitive impairment in the aged IL-6 knockout mice. These data suggested that IL-6 would be a required pro-inflammatory cytokine for the peripheral surgical wounding-induced cognitive impairment. Given this, further studies are warranted to investigate the role of IL-6 in the neuropathogenesis and targeted interventions of POCD.

Peripheral surgical wounding may induce cognitive impairment through interlukin-6-dependent mechanisms in aged mice

PubMed Central

Dong, Yuanlin; Xu, Zhipeng; Huang, Lining; Zhang, Yiying; Xie, Zhongcong

2016-01-01

Post-operative cognitive dysfunction (POCD) is associated with morbidity, mortality and increased cost of medical care. However, the neuropathogenesis and targeted interventions of POCD remain largely to be determined. We have found that the peripheral surgical wounding induces an age-dependent Aβ accumulation, neuroinflammation and cognitive impairment in aged mice. Pro-inflammatory cytokine interlukin-6 (IL-6) has been reported to be associated with cognitive impairment in rodents and humans. However, the role of IL-6 in the neuropathogenesis of POCD is unknown. We therefore employed pharmacological (IL-6 antibody) and genetic (knockout of IL-6) approach to investigate whether IL-6 contributed to the peripheral surgical wounding-induced cognitive impairment in aged mice. Abdominal surgery under local anesthesia (peripheral surgical wounding) was established in 18-month-old wild-type and IL-6 knockout mice (n = 6 to 10 in each group). Brain level of IL-6 and cognitive function in the mice were determined by western blot, ELISA at the end of procedure, and Fear Conditioning System at 7 days after the procedure. The peripheral surgical wounding increased the level of IL-6 in the hippocampus of aged wild-type, but not IL-6 knockout mice. IL-6 antibody ameliorated the peripheral surgical wounding-induced cognitive impairment in the aged wild-type mice. Finally, the peripheral surgical wounding did not induce cognitive impairment in the aged IL-6 knockout mice. These data suggested that IL-6 would be a required pro-inflammatory cytokine for the peripheral surgical wounding-induced cognitive impairment. Given this, further studies are warranted to investigate the role of IL-6 in the neuropathogenesis and targeted interventions of POCD. PMID:28217289

NF-κB inhibition delays DNA damage–induced senescence and aging in mice

PubMed Central

Tilstra, Jeremy S.; Robinson, Andria R.; Wang, Jin; Gregg, Siobhán Q.; Clauson, Cheryl L.; Reay, Daniel P.; Nasto, Luigi A.; St Croix, Claudette M.; Usas, Arvydas; Vo, Nam; Huard, Johnny; Clemens, Paula R.; Stolz, Donna B.; Guttridge, Denis C.; Watkins, Simon C.; Garinis, George A.; Wang, Yinsheng; Niedernhofer, Laura J.; Robbins, Paul D.

2012-01-01

The accumulation of cellular damage, including DNA damage, is thought to contribute to aging-related degenerative changes, but how damage drives aging is unknown. XFE progeroid syndrome is a disease of accelerated aging caused by a defect in DNA repair. NF-κB, a transcription factor activated by cellular damage and stress, has increased activity with aging and aging-related chronic diseases. To determine whether NF-κB drives aging in response to the accumulation of spontaneous, endogenous DNA damage, we measured the activation of NF-κB in WT and progeroid model mice. As both WT and progeroid mice aged, NF-κB was activated stochastically in a variety of cell types. Genetic depletion of one allele of the p65 subunit of NF-κB or treatment with a pharmacological inhibitor of the NF-κB–activating kinase, IKK, delayed the age-related symptoms and pathologies of progeroid mice. Additionally, inhibition of NF-κB reduced oxidative DNA damage and stress and delayed cellular senescence. These results indicate that the mechanism by which DNA damage drives aging is due in part to NF-κB activation. IKK/NF-κB inhibitors are sufficient to attenuate this damage and could provide clinical benefit for degenerative changes associated with accelerated aging disorders and normal aging. PMID:22706308

Dietary broccoli mildly improves neuroinflammation in aged mice but does not reduce lipopolysaccharide-induced sickness behavior.

PubMed

Townsend, Brigitte E; Chen, Yung-Ju; Jeffery, Elizabeth H; Johnson, Rodney W

2014-11-01

Aging is associated with oxidative stress and heightened inflammatory response to infection. Dietary interventions to reduce these changes are therefore desirable. Broccoli contains glucoraphanin, which is converted to sulforaphane (SFN) by plant myrosinase during cooking preparation or digestion. Sulforaphane increases antioxidant enzymes including NAD(P)H quinone oxidoreductase and heme oxygenase I and inhibits inflammatory cytokines. We hypothesized that dietary broccoli would support an antioxidant response in brain and periphery of aged mice and inhibit lipopolysaccharide (LPS)-induced inflammation and sickness. Young adult and aged mice were fed control or 10% broccoli diet for 28 days before an intraperitoneal LPS injection. Social interactions were assessed 2, 4, 8, and 24 hours after LPS, and mRNA was quantified in liver and brain at 24 hours. Dietary broccoli did not ameliorate LPS-induced decrease in social interactions in young or aged mice. Interleukin-1β (IL-1β) expression was unaffected by broccoli consumption but was induced by LPS in brain and liver of adult and aged mice. In addition, IL-1β was elevated in brain of aged mice without LPS. Broccoli consumption decreased age-elevated cytochrome b-245 β, an oxidative stress marker, and reduced glial activation markers in aged mice. Collectively, these data suggest that 10% broccoli diet provides a modest reduction in age-related oxidative stress and glial reactivity, but is insufficient to inhibit LPS-induced inflammation. Thus, it is likely that SFN would need to be provided in supplement form to control the inflammatory response to LPS. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Dietary broccoli mildly improves neuroinflammation in aged mice but does not reduce lipopolysaccharide-induced sickness behavior

PubMed Central

Townsend, Brigitte E.; Chen, Yung-Ju; Jeffery, Elizabeth H.; Johnson, Rodney W.

2015-01-01

Aging is associated with oxidative stress and heightened inflammatory response to infection. Dietary interventions to reduce these changes are therefore desirable. Broccoli contains glucoraphanin, which is converted to sulforaphane (SFN) by plant myrosinase during cooking preparation or digestion. SFN increases antioxidant enzymes including NAD(P)H quinone oxidoreductase (NQO1) and heme oxygenase I (HMOX1) and inhibits inflammatory cytokines. We hypothesized that dietary broccoli would support an antioxidant response in brain and periphery of aged mice and inhibit lipopolysaccharide-induced inflammation and sickness. Young adult and aged mice were fed control or 10% broccoli diet for 28 days prior to an intraperitoneal LPS injection. Social interactions were assessed 2, 4, 8, and 24 h following LPS, and mRNA quantified in liver and brain at 24 h. Dietary broccoli did not ameliorate LPS-induced decrease in social interactions in young or aged mice. Interleukin (IL)-1β expression was unaffected by broccoli consumption but was induced by LPS in brain and liver of adult and aged mice. Additionally, IL-1β was elevated in brain of aged mice without LPS. Broccoli consumption decreased age-elevated cytochrome b-245 β, an oxidative stress marker, and reduced glial activation markers in aged mice. Collectively, these data suggest that 10% broccoli diet provides a modest reduction in age-related oxidative stress and glial reactivity, but is insufficient to inhibit LPS-induced inflammation. Thus, it is likely that SFN would need to be provided in supplement form to control the inflammatory response to LPS. PMID:25439028

Plasticity of lifelong calorie-restricted C57BL/6J mice in adapting to a medium-fat diet intervention at old age.

PubMed

Rusli, Fenni; Boekschoten, Mark V; Borelli, Vincenzo; Sun, Chen; Lute, Carolien; Menke, Aswin L; van den Heuvel, Joost; Salvioli, Stefano; Franceschi, Claudio; Müller, Michael; Steegenga, Wilma T

2018-04-01

Calorie restriction (CR) is a dietary regimen that supports healthy aging. In this study, we investigated the systemic and liver-specific responses caused by a diet switch to a medium-fat (MF) diet in 24-month-old lifelong, CR-exposed mice. This study aimed to increase the knowledge base on dietary alterations of gerontological relevance. Nine-week-old C57BL/6J mice were exposed either to a control, CR, or MF diet. At the age of 24 months, a subset of mice of the CR group was transferred to ad libitumMF feeding (CR-MF). The mice were sacrificed at the age of 28 months, and then, biochemical and molecular analyses were performed. Our results showed that, despite the long-term exposure to the CR regimen, mice in the CR-MF group displayed hyperphagia, rapid weight gain, and hepatic steatosis. However, no hepatic fibrosis/injury or alteration in CR-improved survival was observed in the diet switch group. The liver transcriptomic profile of CR-MF mice largely shifted to a profile similar to the MF-fed animals but leaving ~22% of the 1,578 differentially regulated genes between the CR and MF diet groups comparable with the expression of the lifelong CR group. Therefore, although the diet switch was performed at an old age, the CR-MF-exposed mice showed plasticity in coping with the challenge of a MF diet without developing severe liver pathologies. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Restoration of the immune functions in aged mice by supplementation with a new herbal composition, HemoHIM.

PubMed

Park, Hae-Ran; Jo, Sung-Kee; Jung, Uhee; Yee, Sung-Tae

2008-01-01

The effect of a new herbal composition, HemoHIM, on immune functions was examined in aged mice, in which various immune responses had been impaired. The composition HemoHIM was prepared by adding the ethanol-insoluble fraction to the total water extract of a mixture of three edible herbs, Angelica Radix, Cnidium Rhizoma and Paeonia Radix. Supplementation to the aged mice with HemoHIM restored the proliferative response and cytokine production of splenocytes with a response to ConA. Also, HemoHIM recovered the NK cell activity which had been impaired in the aged mice. Meanwhile aging is known to reduce the Th1-like function, but not the Th2-like function, resulting in a Th1/Th2 imbalance. HemoHIM restored the Th1/Th2 balance in the aged mice through enhanced IFN-gamma and IgG2a production, and conversely a reduced IL-4 and IgG1 production. It was found that one factor for the Th1/Th2 imbalance in the aged mice was a lower production of IL-12p70. However, HemoHIM restored the IL-12p70 production in the aged mice. These results suggested that HemoHIM was effective for the restoration of impaired immune functions of the aged mice and therefore could be a good recommendation for immune restoration in elderly humans. Copyright (c) 2007 John Wiley & Sons, Ltd.

Milk fat globule membrane supplementation with voluntary running exercise attenuates age-related motor dysfunction by suppressing neuromuscular junction abnormalities in mice.

PubMed

Yano, Michiko; Minegishi, Yoshihiko; Sugita, Satoshi; Ota, Noriyasu

2017-10-15

Age-related loss of skeletal muscle mass and function attenuates physical performance, and maintaining fine muscle innervation is known to play an important role in its prevention. We had previously shown that consumption of milk fat globule membrane (MFGM) with habitual exercise improves the muscle mass and motor function in humans and mice. Improvement of neuromuscular junction (NMJ) was suggested as one of the mechanisms underlying these effects. In this study, we evaluated the effect of MFGM intake combined with voluntary running (MFGM-VR) on morphological changes of NMJ and motor function in aging mice. Seven months following the intervention, the MFGM-VR group showed a significantly improved motor coordination in the rotarod test and muscle force in the grip strength test compared with the control group at 13 and 14months of age, respectively. In 14-month old control mice, the extensor digitorum longus muscle showed increased abnormal NMJs, such as fragmentation and denervation, compared with 6-month old young mice. However, such age-related deteriorations of NMJs were significantly suppressed in the MFGM-VR group. Increase in the expression of NMJ formation-related genes, such as agrin and LDL Receptor Related Protein 4 (LRP4), might contribute to this beneficial effect. Rotarod performance and grip strength showed significant negative correlation with the status of denervation and fragmentation of NMJs. These results suggest that MFGM intake with voluntary running exercise effectively suppresses age-related morphological deterioration of NMJ, thus contributing to improvement of motor function. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Metabolic Stress Induces Cognitive Disturbances and Inflammation in Aged Mice: Protective Role of Resveratrol.

PubMed

Palomera-Ávalos, Veronica; Griñán-Ferré, Christian; Izquierdo, Vanesa; Camins, Antonio; Sanfeliu, Coral; Pallàs, Mercè

2017-06-01

Inflammation and oxidative stress (OS) are key points in age progression. Both processes impact negatively in cognition and in brain functions. Resveratrol (RV) has been postulated as a potent antioxidant natural compound, with rejuvenating properties. Inducing a metabolic stress by high-fat (HF) diet in aged C56/BL6 (24 months) led to cognitive disturbances compared with control age mated and with young mice. These changes were prevented by RV. Molecular determinations demonstrated a significant increase in some inflammatory parameters (TNF-α, Cxcl10, IL-1, IL-6, and Ccl3) in old mice, but slight changes in OS machinery. RV mainly induced the recovery of the metabolically stressed animals. The study of key markers involved in senescence and rejuvenation (mitochondrial biogenesis and Sirt1-AMPK-PGC1-α) demonstrated that RV is also able to modulate the changes in these cellular metabolic pathways. Moreover, changes of epigenetic marks (methylation and acetylation) that are depending on OS were demonstrated. On the whole, results showed the importance of integrative role of different cellular mechanisms in the deleterious effects of age in cognition and the beneficial role of RV. The work presented in this study showed a wide range of processes modified in old age and by metabolic stress, weighting the importance of each one and the role of RV as a possible strategy for fighting against.

Effect of Anti-Sclerostin Therapy and Osteogenesis Imperfecta on Tissue-level Properties in Growing and Adult Mice While Controlling for Tissue Age

PubMed Central

Sinder, Benjamin P.; Lloyd, William R.; Salemi, Joseph D.; Marini, Joan C.; Caird, Michelle S.; Morris, Michael D.; Kozloff, Kenneth M.

2016-01-01

Bone composition and biomechanics at the tissue-level are important contributors to whole bone strength. Sclerostin antibody (Scl-Ab) is a candidate anabolic therapy for the treatment of osteoporosis that increases bone formation, bone mass, and bone strength in animal studies, but its effect on bone quality at the tissue-level has received little attention. Pre-clinical studies of Scl-Ab have recently expanded to include diseases with altered collagen and material properties such as Osteogenesis Imperfecta (OI). The purpose of this study was to investigate the role of Scl-Ab on bone quality by determining bone material composition and tissue-level mechanical properties in normal wild type (WT) tissue, as well as mice with a typical OI Gly→Cys mutation (Brtl/+) in type I collagen. Rapidly growing (3-week-old) and adult (6-month-old) WT and Brtl/+ mice were treated for 5 weeks with Scl-Ab. Fluorescent guided tissue-level bone composition analysis (Raman spectroscopy) and biomechanical testing (nanoindentation) were performed at multiple tissue ages. Scl-Ab increased mineral to matrix in adult WT and Brtl/+ at tissue ages of 2–4wks. However, no treatment related changes were observed in mineral to matrix levels at mid-cortex, and elastic modulus was not altered by Scl-Ab at any tissue age. Increased mineral-to-matrix was phenotypically observed in adult Brtl/+ OI mice (at tissue ages >3wk) and rapidly growing Brtl/+ (at tissue ages > 4wk) mice compared to WT. At identical tissue ages defined by fluorescent labels adult mice had generally lower mineral to matrix ratios and a greater elastic modulus than rapidly growing mice, demonstrating that bone matrix quality can be influenced by animal age and tissue age alike. In summary, these data suggest that Scl-Ab alters the matrix chemistry of newly formed bone while not affecting the elastic modulus, induces similar changes between Brtl/+ and WT mice, and provides new insight into the interaction between tissue age

Effect of anti-sclerostin therapy and osteogenesis imperfecta on tissue-level properties in growing and adult mice while controlling for tissue age.

PubMed

Sinder, Benjamin P; Lloyd, William R; Salemi, Joseph D; Marini, Joan C; Caird, Michelle S; Morris, Michael D; Kozloff, Kenneth M

2016-03-01

Bone composition and biomechanics at the tissue-level are important contributors to whole bone strength. Sclerostin antibody (Scl-Ab) is a candidate anabolic therapy for the treatment of osteoporosis that increases bone formation, bone mass, and bone strength in animal studies, but its effect on bone quality at the tissue-level has received little attention. Pre-clinical studies of Scl-Ab have recently expanded to include diseases with altered collagen and material properties such as osteogenesis imperfecta (OI). The purpose of this study was to investigate the role of Scl-Ab on bone quality by determining bone material composition and tissue-level mechanical properties in normal wild type (WT) tissue, as well as mice with a typical OI Gly➔Cys mutation (Brtl/+) in type I collagen. Rapidly growing (3-week-old) and adult (6-month-old) WT and Brtl/+ mice were treated for 5weeks with Scl-Ab. Fluorescent guided tissue-level bone composition analysis (Raman spectroscopy) and biomechanical testing (nanoindentation) were performed at multiple tissue ages. Scl-Ab increased mineral to matrix in adult WT and Brtl/+ at tissue ages of 2-4wks. However, no treatment related changes were observed in mineral to matrix levels at mid-cortex, and elastic modulus was not altered by Scl-Ab at any tissue age. Increased mineral-to-matrix was phenotypically observed in adult Brtl/+ OI mice (at tissue ages>3wks) and rapidly growing Brtl/+ (at tissue ages>4wks) mice compared to WT. At identical tissue ages defined by fluorescent labels, adult mice had generally lower mineral to matrix ratios and a greater elastic modulus than rapidly growing mice, demonstrating that bone matrix quality can be influenced by animal age and tissue age alike. In summary, these data suggest that Scl-Ab alters the matrix chemistry of newly formed bone while not affecting the elastic modulus, induces similar changes between Brtl/+ and WT mice, and provides new insight into the interaction between tissue age and

Aged Tg2576 mice are impaired on social memory and open field habituation tests.

PubMed

Deacon, R M J; Koros, E; Bornemann, K D; Rawlins, J N P

2009-02-11

In a previous publication [Deacon RMJ, Cholerton LL, Talbot K, Nair-Roberts RG, Sanderson DJ, Romberg C, et al. Age-dependent and -independent behavioral deficits in Tg2576 mice. Behav Brain Res 2008;189:126-38] we found that very few cognitive tests were suitable for demonstrating deficits in Tg2576 mice, an amyloid over-expression model of Alzheimer's disease, even at 23 months of age. However, in a retrospective analysis of a separate project on these mice, tests of social memory and open field habituation revealed large cognitive impairments. Controls showed good open field habituation, but Tg2576 mice were hyperactive and failed to habituate. In the test of social memory for a juvenile mouse, controls showed considerably less social investigation on the second meeting, indicating memory of the juvenile, whereas Tg2576 mice did not show this decrement.As a control for olfactory sensitivity, on which social memory relies, the ability to find a food pellet hidden under wood chip bedding was assessed. Tg2576 mice found the pellet as quickly as controls. As this test requires digging ability, this was independently assessed in tests of burrowing and directly observed digging. In line with previous results and the hippocampal dysfunction characteristic of aged Tg2576 mice, they both burrowed and dug less than controls.

Fat-specific Dicer deficiency accelerates aging and mitigates several effects of dietary restriction in mice.

PubMed

Reis, Felipe C G; Branquinho, Jéssica L O; Brandão, Bruna B; Guerra, Beatriz A; Silva, Ismael D; Frontini, Andrea; Thomou, Thomas; Sartini, Loris; Cinti, Saverio; Kahn, C Ronald; Festuccia, William T; Kowaltowski, Alicia J; Mori, Marcelo A

2016-06-01

Aging increases the risk of type 2 diabetes, and this can be prevented by dietary restriction (DR). We have previously shown that DR inhibits the downregulation of miRNAs and their processing enzymes - mainly Dicer - that occurs with aging in mouse white adipose tissue (WAT). Here we used fat-specific Dicer knockout mice (AdicerKO) to understand the contributions of adipose tissue Dicer to the metabolic effects of aging and DR. Metabolomic data uncovered a clear distinction between the serum metabolite profiles of Lox control and AdicerKO mice, with a notable elevation of branched-chain amino acids (BCAA) in AdicerKO. These profiles were associated with reduced oxidative metabolism and increased lactate in WAT of AdicerKO mice and were accompanied by structural and functional changes in mitochondria, particularly under DR. AdicerKO mice displayed increased mTORC1 activation in WAT and skeletal muscle, where Dicer expression is not affected. This was accompanied by accelerated age-associated insulin resistance and premature mortality. Moreover, DR-induced insulin sensitivity was abrogated in AdicerKO mice. This was reverted by rapamycin injection, demonstrating that insulin resistance in AdicerKO mice is caused by mTORC1 hyperactivation. Our study evidences a DR-modulated role for WAT Dicer in controlling metabolism and insulin resistance.

Fat-specific Dicer deficiency accelerates aging and mitigates several effects of dietary restriction in mice

PubMed Central

Reis, Felipe C. G.; Branquinho, Jéssica L. O.; Brandão, Bruna B.; Guerra, Beatriz A.; Silva, Ismael D.; Frontini, Andrea; Thomou, Thomas; Sartini, Loris; Cinti, Saverio; Kahn, C. Ronald; Festuccia, William T.; Kowaltowski, Alicia J.; Mori, Marcelo A.

2016-01-01

Aging increases the risk of type 2 diabetes, and this can be prevented by dietary restriction (DR). We have previously shown that DR inhibits the downregulation of miRNAs and their processing enzymes - mainly Dicer - that occurs with aging in mouse white adipose tissue (WAT). Here we used fat-specific Dicer knockout mice (AdicerKO) to understand the contributions of adipose tissue Dicer to the metabolic effects of aging and DR. Metabolomic data uncovered a clear distinction between the serum metabolite profiles of Lox control and AdicerKO mice, with a notable elevation of branched-chain amino acids (BCAA) in AdicerKO. These profiles were associated with reduced oxidative metabolism and increased lactate in WAT of AdicerKO mice and were accompanied by structural and functional changes in mitochondria, particularly under DR. AdicerKO mice displayed increased mTORC1 activation in WAT and skeletal muscle, where Dicer expression is not affected. This was accompanied by accelerated age-associated insulin resistance and premature mortality. Moreover, DR-induced insulin sensitivity was abrogated in AdicerKO mice. This was reverted by rapamycin injection, demonstrating that insulin resistance in AdicerKO mice is caused by mTORC1 hyperactivation. Our study evidences a DR-modulated role for WAT Dicer in controlling metabolism and insulin resistance. PMID:27241713

Influence of Sex and Age on Natural Resistance to St. Louis Encephalitis Virus Infection in Mice

PubMed Central

Andersen, Arthur A.; Hanson, Robert P.

1974-01-01

A difference was observed in susceptibility of adult male and female mice to St. Louis encephalitis (SLE) virus as measured by the death rate after intravenous challenge. Female mice that had susceptibility similar to that of males at 2 months of age had increased resistance to SLE virus at 3 and 4 months of age. The increased resistance occurred after sexual maturity, indicating that the resistance factor possibly was related to an aging process in the female. The susceptibility of male mice remained unchanged over the 2- to 4-month period. Neither pregnancy nor castration had any effect on resistance of adult mice to St. Louis encephalitis virus. PMID:4857422

Ultraviolet Radiation–Induced Cataract in Mice: The Effect of Age and the Potential Biochemical Mechanism

PubMed Central

Zhang, Jie; Yan, Hong; Löfgren, Stefan; Tian, Xiaoli; Lou, Marjorie F.

2012-01-01

Purpose. To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV). Methods. Young and old C57BL/6 mice were exposed to broadband UVB+UVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins (PSSGs) were detected by immunoblotting using GSH antibody. Western blot analysis was also done for the expression levels of TTase and Trx. Results. Both age groups developed epithelial and superficial anterior subcapsular cataract at 2 days postexposure. The lens GSH level and G3PD activity were decreased, and PSSGs were elevated in both age groups, but more prominent in the older mice. TTase and Trx activity and protein expression were elevated only in the young mice. Interestingly, lens TTase and Trx in the young mice showed a transient increase, peaking at 2 days after UV exposure and returning to baseline at day 8, corroborated by lens transparency. Conclusions. The lenses of old mice were more susceptible to UV radiation–induced cataract. The upregulated TTase and Trx likely provided oxidation damage repair in the young mice. PMID:23010639

Protracted downregulation of CX3CR1 on microglia of aged mice after lipopolysaccharide challenge

PubMed Central

Wynne, Angela M; Henry, Christopher J.; Huang, Yan; Cleland, Anthony; Godbout, Jonathan P.

2010-01-01

Fractalkine (CX3CL1) to fractalkine receptor (CX3CR1) interactions in the brain are involved in the modulation of microglial activation. Our recent findings indicate that there is microglial hyperactivity in the aged brain during an inflammatory challenge. The underlying cause of this amplified microglial response in the aged brain is unknown. Therefore, the purpose of this study was to determine the degree to which age-associated impairments of CX3CL1 and CX3CR1 in the brain contribute to exaggerated microglial activation after intraperitoneal (i.p.) injection of lipopolysaccharide (LPS). Here we show that CX3CL1 protein was reduced in the brain of aged (18–22 mo) BALB/c mice compared to adult (3–6 mo) controls. CX3CL1 protein, however, was unaltered by LPS injection. Next, CX3CR1 levels were determined in microglia (CD11b+/CD45low) isolated by Percoll-density gradient separation at 4 and 24 h after LPS injection. Flow cytometric and mRNA analyses of these microglia showed that LPS-injection caused a marked decrease of CX3CR1 and a simultaneous increase of IL-1β at 4 h after LPS injection. While surface expression of CX3CR1 was enhanced on microglia of adult mice by 24 h, it was still significantly downregulated on a subset of microglia from aged mice. This protracted reduction of CX3CR1 corresponded with a delayed recovery from sickness behavior, prolonged IL-1β induction, and decreased TGFβ expression in the aged brain. In the last set of studies BV2 microglia were used to determine effect of TGFβ on CX3CR1. These results showed that TGFβ enhanced CX3CR1 expression and attenuated the LPS-induced increase in IL-1β expression. PMID:20570721

Maintenance of muscle mass and load-induced growth in Muscle RING Finger 1 null mice with age.

PubMed

Hwee, Darren T; Baehr, Leslie M; Philp, Andrew; Baar, Keith; Bodine, Sue C

2014-02-01

Age-related loss of muscle mass occurs to varying degrees in all individuals and has a detrimental effect on morbidity and mortality. Muscle RING Finger 1 (MuRF1), a muscle-specific E3 ubiquitin ligase, is believed to mediate muscle atrophy through the ubiquitin proteasome system (UPS). Deletion of MuRF1 (KO) in mice attenuates the loss of muscle mass following denervation, disuse, and glucocorticoid treatment; however, its role in age-related muscle loss is unknown. In this study, skeletal muscle from male wild-type (WT) and MuRF1 KO mice was studied up to the age of 24 months. Muscle mass and fiber cross-sectional area decreased significantly with age in WT, but not in KO mice. In aged WT muscle, significant decreases in proteasome activities, especially 20S and 26S β5 (20-40% decrease), were measured and were associated with significant increases in the maladaptive endoplasmic reticulum (ER) stress marker, CHOP. Conversely, in aged MuRF1 KO mice, 20S or 26S β5 proteasome activity was maintained or decreased to a lesser extent than in WT mice, and no increase in CHOP expression was measured. Examination of the growth response of older (18 months) mice to functional overload revealed that old WT mice had significantly less growth relative to young mice (1.37- vs. 1.83-fold), whereas old MuRF1 KO mice had a normal growth response (1.74- vs. 1.90-fold). These data collectively suggest that with age, MuRF1 plays an important role in the control of skeletal muscle mass and growth capacity through the regulation of cellular stress. © 2013 the Anatomical Society and John Wiley & Sons Ltd.

Role of CD11b+Gr-1+ myeloid cells in AGEs-induced myocardial injury in a mice model of acute myocardial infarction.

PubMed

Yao, Tongqing; Lu, Wenbin; Zhu, Jian; Jin, Xian; Ma, Genshan; Wang, Yuepeng; Meng, Shu; Zhang, Yachen; Li, Yigang; Shen, Chengxing

2015-01-01

Polymorph neutrophils are the predominant inflammatory cells and play a crucial role on the pathogenesis of myocardial injury at the early stage of acute myocardial infarction (AMI). However, the precursors and the differentiation of neutrophils are not fully understood. Here we explored the role of CD11b+Gr-1+ myeloid-derived suppressor cells (MDSCs) on myocardial injury in the absence and presence of advanced glycation end-products (AGEs) in a mice model of AMI. Male C57BL/6J mice were selected. Fluorescent actived cell sortor (FACS) data demonstrated significantly increased CD11b+Gr-1+ MDSCs both in peripheral blood circulation and in the ischemic myocardium at 24 hours post AMI. Quantitative-real-time PCR results also revealed significantly upregulated CD11b and Ly6G mRNA expression in the ischemic myocardium. AGEs treatment further aggravated these changes in AMI mice but not in sham mice. Moreover, AGEs treatment also significantly increased infarction size and enhanced cardiomyocyte apoptosis. The mRNA expression of pro-inflammatory cytokine IL-6 and iNOS2 was also significantly increased in AMI + AGEs group compared to AMI group. These data suggest enhanced infiltration of MDSCs by AGEs contributes to aggravated myocardial injury in AMI mice, which might be one of the mechanisms responsible for severer myocardial injury in AMI patients complicating diabetes.

Characterization of age-associated changes in peripheral organ and brain region weights in C57BL/6 mice.

PubMed

Lessard-Beaudoin, Mélissa; Laroche, Mélissa; Demers, Marie-Josée; Grenier, Guillaume; Graham, Rona K

2015-03-01

In order to further understand age-related physiological changes and to have in depth reference values for C57BL/6 mice, we undertook a study to assess the effects of aging on peripheral organ weights, and brain region weights in wild type C57BL/6 male mice. Peripheral organs, body and brain region weights were collected from young (3-4 months), mid (12 months), old (23-28 months) and very old (>30 months) mice. Significant increases are observed with aging in body, liver, heart, kidney and spleen organ weights. A decrease in organ weight is observed with aging in liver and kidney only in the very old mice. In contrast, testes weight decreases with age. Within the brain, hippocampi, striata and olfactory bulbs weight decreases with age. These data further our knowledge of the anatomical and biological changes that occur with aging and provide reference values for physiological-based pharmacokinetic studies in C57BL/6 mice. Copyright © 2015 Elsevier Inc. All rights reserved.

Retaining Residual Ovarian Tissue following Ovarian Failure Has Limited Influence on Bone Loss in Aged Mice

PubMed Central

Craig, Zelieann R.; Marion, Samuel L.; Funk, Janet L.; Bouxsein, Mary L.; Hoyer, Patricia B.

2010-01-01

Previous work showed that retaining residual ovarian tissue protects young mice from accelerated bone loss following ovarian failure. The present study was designed to determine whether this protection is also present in aged animals. Aged (9–12 months) C57BL/6Hsd female mice were divided into: CON (vehicle), VCD (160 mg/kg; 15d), or OVX (ovariectomized). Lumbar BMD was monitored by DXA and μCT used to assess vertebral microarchitecture. BMD was not different between VCD and CON at any time point but was lower (P < .05) than baseline, starting 1 month after ovarian failure in VCD and OVX mice. Following μCT analysis there were no differences between CON and VCD, but OVX mice had lower bone volume fraction, trabecular thickness, and a trend for decreased connectivity density. These findings provide evidence that retention of residual ovarian tissue may protect aged follicle-depleted mice from accelerated bone loss to a lesser extent than that observed in young mice. PMID:20948577

Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice.

PubMed

Wheelan, Nicola; Webster, Scott P; Kenyon, Christopher J; Caughey, Sarah; Walker, Brian R; Holmes, Megan C; Seckl, Jonathan R; Yau, Joyce L W

2015-04-01

High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sexual rest and post-meiotic sperm ageing in house mice.

PubMed

Firman, R C; Young, F J; Rowe, D C; Duong, H T; Gasparini, C

2015-07-01

Fertilization by aged sperm can result in adverse fitness consequences for both males and females. Sperm storage during male sexual rest could provide an environment for post-meiotic sperm senescence causing a deterioration in the quality of stored sperm, possibly impacting on both sperm performance (e.g. swimming ability) and DNA quality. Here, we compared the proportion of sperm with fragmented DNA, an indicator of structural damage of DNA within the sperm cell, among males that had been sexually rested for approximately 2 months, to that of males that had mated recently. We found no evidence of intra-epididymal sperm DNA damage or any impairment in sperm performance, and consequently no evidence of post-meiotic sperm senescence. Our results suggest that male house mice are likely to possess mechanisms that function to ensure that their sperm reserves remain stocked with 'young', viable sperm during periods of sexual inactivity. We also discuss the possibility that our experimental design leads to no difference in the age of sperm among males from the two mating treatments. Post-meiotic sperm senescence is especially relevant under sperm competition. Thus, we sourced mice from populations that differed in their levels of post-copulatory sexual selection, enabling us to gain insight into how selection for higher sperm production influences the rate of sperm ageing and levels of DNA fragmentation. We found that males from the population that produced the highest number of sperm also had the smallest proportion of DNA-fragmented sperm and discuss this outcome in relation to selection acting upon males to ensure that they produce ejaculates with high-quality sperm that are successful in achieving fertilizations under competitive conditions. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Differential Effects of Leucine Supplementation in Young and Aged Mice at the Onset of Skeletal Muscle Regeneration

PubMed Central

Perry, Richard A.; Brown, Lemuel A.; Lee, David E.; Brown, Jacob L.; Baum, Jamie I.; Greene, Nicholas P.; Washington, Tyrone A.

2016-01-01

Aging decreases the ability of skeletal muscle to respond to injury. Leucine has been demonstrated to target protein synthetic pathways in skeletal muscle thereby enhancing this response. However, the effect of aging on leucine-induced alterations in protein synthesis at the onset of skeletal muscle regeneration has not been fully elucidated. The purpose of this study was to determine if aging alters skeletal muscle regeneration and leucine-induced alterations in markers of protein synthesis. The tibialis anterior of young (3 months) and aged (24 months) female C57BL/6J mice were injected with either bupivacaine or PBS, and the mice were given ad libitum access to leucine-supplemented or normal drinking water. Protein and gene expression of markers of protein synthesis and degradation, respectively, were analyzed at three days post-injection. Following injury in young mice, leucine supplementation was observed to elevate only p-p70S6K. In aged mice, leucine was shown to elicit higher p-mTOR content with and without injury, and p-4EBP-1 content post-injury. Additionally in aged mice, leucine was shown to elicit higher content of relative p70S6K post-injury. Our study shows that leucine supplementation affects markers of protein synthesis at the onset of skeletal muscle regeneration differentially in young and aged mice. PMID:27327351

Probiotic Dahi containing Lactobacillus acidophilus and Bifidobacterium bifidum alleviates age-inflicted oxidative stress and improves expression of biomarkers of ageing in mice.

PubMed

Kaushal, Deepti; Kansal, Vinod K

2012-02-01

The potential benefiting effects of probiotic Dahi on age-inflicted accumulation of oxidation products, antioxidant enzymes and expression of biomarkers of ageing were evaluated in mice. Probiotic Dahi were prepared by co-culturing in buffalo milk (3% fat) Dahi bacteria (Lactococcus lactis ssp. cremoris NCDC-86 and Lactococcus lactis ssp. lactis biovar diacetylactis NCDC-60) along with selected strain of Lactobacillus acidophilus LaVK2 (La-Dahi) or combined L. acidophilus and Bifidobacterium bifidum BbVK3 (LaBb-Dahi). Four groups of 12 months old mice (6 each) were fed for 4 months supplements (5 g/day) of buffalo milk (3% fat), Dahi, La-Dahi and LaBb-Dahi, respectively, with basal diet. The activities of catalase (CAT) and glutathione peroxidase (GPx) declined and the contents of oxidation products, thiobarbituric acid reactive substances (TBARS) and protein carbonyls, increased in red blood corpuscles (RBCs), liver, kidney and heart tissues and superoxide dismutase (SOD) activity increased in RBCs and hepatic tissues during ageing of mice. Feeding ageing mice with La-Dahi or LaBb-Dahi increased CAT activity in all the four tissues, and GPx activity in RBCs and hepatic tissue, and a significant decline in TBARS in plasma, kidney and hepatic tissues and protein carbonyls in plasma. Feeding mice with probiotic Dahi also reversed age related decline in expression of biomarkers of ageing, peroxisome proliferators activated receptor-α, senescence marker protein-30 (SMP-30) and klotho in hepatic and kidney tissues. The present study suggests that probiotic Dahi containing selected strains of bacteria can be used as a potential nutraceutical intervention to combat oxidative stress and molecular alterations associated with ageing.

Identification of a sustainable two-plant diet that effectively prevents age-related metabolic syndrome and extends lifespan in aged mice.

PubMed

Li, Xiang-Yong; Liu, Ying-Hua; Wang, Bin; Chen, Chih-Yu; Zhang, Hong-Man; Kang, Jing X

2018-01-01

The current system of food production is linked to both the increasing prevalence of chronic disease and the deterioration of the environment, and thereby calls for novel ways of producing nutritious foods in a sustainable manner. In the "longevity village" of Bama, China, we have identified two plant foods, hemp seed and bitter vegetable (Sonchus oleraceus), that are commonly consumed by its residents and grow abundantly in unfarmed land without fertilizers or pesticides. Here, we show that a diet composed of these two foods (the "HB diet") provides a sufficient variety of nutrients and confers significant health benefits. Aged mice allowed ad libitum access to the HB diet not only had longer life spans and improved cognitive function but were also protected against age-related metabolic syndrome, fatty liver, gut dysbiosis and chronic inflammation compared to aged mice fed a control Western diet. Furthermore, longevity-related genes (including 5'adenosine monophosphate-activated protein kinase, sirtuin 1, nuclear respiratory factor 1 and forkhead box O3) were significantly up-regulated, while aging-related genes (including mammalian target of rapamycin and nuclear factor kappa B) were down-regulated. These results demonstrate that the HB diet is capable of promoting health and longevity, and present a sustainable source of healthy foods that can help control the prevalence of chronic diseases and reduce agricultural impact on the environment. Copyright © 2017 Elsevier Inc. All rights reserved.

Reversal of glial and neurovascular markers of unhealthy brain aging by exercise in middle-aged female mice.

PubMed

Latimer, Caitlin S; Searcy, James L; Bridges, Michael T; Brewer, Lawrence D; Popović, Jelena; Blalock, Eric M; Landfield, Philip W; Thibault, Olivier; Porter, Nada M

2011-01-01

Healthy brain aging and cognitive function are promoted by exercise. The benefits of exercise are attributed to several mechanisms, many which highlight its neuroprotective role via actions that enhance neurogenesis, neuronal morphology and/or neurotrophin release. However, the brain is also composed of glial and vascular elements, and comparatively less is known regarding the effects of exercise on these components in the aging brain. Here, we show that aerobic exercise at mid-age decreased markers of unhealthy brain aging including astrocyte hypertrophy, a hallmark of brain aging. Middle-aged female mice were assigned to a sedentary group or provided a running wheel for six weeks. Exercise decreased hippocampal astrocyte and myelin markers of aging but increased VEGF, a marker of angiogenesis. Brain vascular casts revealed exercise-induced structural modifications associated with improved endothelial function in the periphery. Our results suggest that age-related astrocyte hypertrophy/reactivity and myelin dysregulation are aggravated by a sedentary lifestyle and accompanying reductions in vascular function. However, these effects appear reversible with exercise initiated at mid-age. As this period of the lifespan coincides with the appearance of multiple markers of brain aging, including initial signs of cognitive decline, it may represent a window of opportunity for intervention as the brain appears to still possess significant vascular plasticity. These results may also have particular implications for aging females who are more susceptible than males to certain risk factors which contribute to vascular aging.

Reversal of Glial and Neurovascular Markers of Unhealthy Brain Aging by Exercise in Middle-Aged Female Mice

PubMed Central

Latimer, Caitlin S.; Searcy, James L.; Bridges, Michael T.; Brewer, Lawrence D.; Popović, Jelena; Blalock, Eric M.; Landfield, Philip W.; Thibault, Olivier; Porter, Nada M.

2011-01-01

Healthy brain aging and cognitive function are promoted by exercise. The benefits of exercise are attributed to several mechanisms, many which highlight its neuroprotective role via actions that enhance neurogenesis, neuronal morphology and/or neurotrophin release. However, the brain is also composed of glial and vascular elements, and comparatively less is known regarding the effects of exercise on these components in the aging brain. Here, we show that aerobic exercise at mid-age decreased markers of unhealthy brain aging including astrocyte hypertrophy, a hallmark of brain aging. Middle-aged female mice were assigned to a sedentary group or provided a running wheel for six weeks. Exercise decreased hippocampal astrocyte and myelin markers of aging but increased VEGF, a marker of angiogenesis. Brain vascular casts revealed exercise-induced structural modifications associated with improved endothelial function in the periphery. Our results suggest that age-related astrocyte hypertrophy/reactivity and myelin dysregulation are aggravated by a sedentary lifestyle and accompanying reductions in vascular function. However, these effects appear reversible with exercise initiated at mid-age. As this period of the lifespan coincides with the appearance of multiple markers of brain aging, including initial signs of cognitive decline, it may represent a window of opportunity for intervention as the brain appears to still possess significant vascular plasticity. These results may also have particular implications for aging females who are more susceptible than males to certain risk factors which contribute to vascular aging. PMID:22046366

Alterations in Skeletal Muscle Fatty Acid Handling Predisposes Middle-Aged Mice to Diet-Induced Insulin Resistance

PubMed Central

Koonen, Debby P.Y.; Sung, Miranda M.Y.; Kao, Cindy K.C.; Dolinsky, Vernon W.; Koves, Timothy R.; Ilkayeva, Olga; Jacobs, René L.; Vance, Dennis E.; Light, Peter E.; Muoio, Deborah M.; Febbraio, Maria; Dyck, Jason R.B.

2010-01-01

OBJECTIVE Although advanced age is a risk factor for type 2 diabetes, a clear understanding of the changes that occur during middle age that contribute to the development of skeletal muscle insulin resistance is currently lacking. Therefore, we sought to investigate how middle age impacts skeletal muscle fatty acid handling and to determine how this contributes to the development of diet-induced insulin resistance. RESEARCH DESIGN AND METHODS Whole-body and skeletal muscle insulin resistance were studied in young and middle-aged wild-type and CD36 knockout (KO) mice fed either a standard or a high-fat diet for 12 weeks. Molecular signaling pathways, intramuscular triglycerides accumulation, and targeted metabolomics of in vivo mitochondrial substrate flux were also analyzed in the skeletal muscle of mice of all ages. RESULTS Middle-aged mice fed a standard diet demonstrated an increase in intramuscular triglycerides without a concomitant increase in insulin resistance. However, middle-aged mice fed a high-fat diet were more susceptible to the development of insulin resistance—a condition that could be prevented by limiting skeletal muscle fatty acid transport and excessive lipid accumulation in middle-aged CD36 KO mice. CONCLUSION Our data provide insight into the mechanisms by which aging becomes a risk factor for the development of insulin resistance. Our data also demonstrate that limiting skeletal muscle fatty acid transport is an effective approach for delaying the development of age-associated insulin resistance and metabolic disease during exposure to a high-fat diet. PMID:20299464

Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice

PubMed Central

Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

2016-01-01

Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg−1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo. PMID:26608944

Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice.

PubMed

Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

2016-01-01

Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.

Blueberry supplementation improves memory in middle-aged mice fed a high-fat diet.

PubMed

Carey, Amanda N; Gomes, Stacey M; Shukitt-Hale, Barbara

2014-05-07

Consuming a high-fat diet may result in behavioral deficits similar to those observed in aging animals. It has been demonstrated that blueberry supplementation can allay age-related behavioral deficits. To determine if supplementation of a high-fat diet with blueberries offers protection against putative high-fat diet-related declines, 9-month-old C57Bl/6 mice were maintained on low-fat (10% fat calories) or high-fat (60% fat calories) diets with and without 4% freeze-dried blueberry powder. Novel object recognition memory was impaired by the high-fat diet; after 4 months on the high-fat diet, mice spent 50% of their time on the novel object in the testing trial, performing no greater than chance performance. Blueberry supplementation prevented recognition memory deficits after 4 months on the diets, as mice on this diet spent 67% of their time on the novel object. After 5 months on the diets, mice consuming the high-fat diet passed through the platform location less often than mice on low-fat diets during probe trials on days 2 and 3 of Morris water maze testing, whereas mice consuming the high-fat blueberry diet passed through the platform location as often as mice on the low-fat diets. This study is a first step in determining if incorporating more nutrient-dense foods into a high-fat diet can allay cognitive dysfunction.

Chronic acarbose treatment alleviates age-related behavioral and biochemical changes in SAMP8 mice.

PubMed

Tong, Jing-Jing; Chen, Gui-Hai; Wang, Fang; Li, Xue-Wei; Cao, Lei; Sui, Xu; Tao, Fei; Yan, Wen-Wen; Wei, Zhao-Jun

2015-05-01

The administration of maintaining the homeostasis of insulin/insulin-like growth factor 1 (IGF-1) signaling and/or glucose metabolism may reverse brain aging. In the present study, we investigated the effect of acarbose, an inhibitor of α-glucosidase, on age-related behavioral and biochemical changes. The SAMP8 mice were randomly divided into old control group and acarbose-treatment group. The mice in the acarbose group were administered acarbose (20 mg/kg/d, dissolved in drinking water) orally from 3 to 9 months of age when a new group of 3-month-old mice was added as young controls. The results showed that the aged controls exhibited declines in sensorimotor ability, open field anxiety, spatial and non-spatial memory abilities, decreased serum insulin levels, increased IGF-1 receptor and synaptotagmin 1 (Syt1) levels and decreased insulin receptor, brain-derived neurotrophic factor (BDNF) and syntaxin 1 (Stx1) levels in the hippocampal layers. The age-related behavioral deficits correlated with the serological and histochemical data. Chronic acarbose treatment relieved these age-related changes, especially with respect to learning and memory abilities. This protective effect of acarbose on age-related behavioral impairments might be related to changes in the insulin system and the levels of BDNF, IGF-1R, and the pre-synaptic proteins Syt1 and Stx1. In conclusion, long-term treatment with acarbose ameliorated the behavioral deficits and biochemical changes in old SAMP8 mice and promoted successful aging. This study provides insight into the potential of acarbose for the treatment of brain aging. Copyright © 2015 Elsevier B.V. All rights reserved.

Chronic Endurance Exercise Impairs Cardiac Structure and Function in Middle-Aged Mice with Impaired Nrf2 Signaling

PubMed Central

Shanmugam, Gobinath; Narasimhan, Madhusudhanan; Conley, Robbie L.; Sairam, Thiagarajan; Kumar, Ashutosh; Mason, Ronald P.; Sankaran, Ramalingam; Hoidal, John R.; Rajasekaran, Namakkal S.

2017-01-01

Nuclear factor erythroid 2 related factor 2 (Nrf2) signaling maintains the redox homeostasis and its activation is shown to suppress cardiac maladaptation. Earlier we reported that acute endurance exercise (2 days) evoked antioxidant cytoprotection in young WT animals but not in aged WT animals. However, the effect of repeated endurance exercise during biologic aging (WT) characterized by an inherent deterioration in Nrf2 signaling and pathological aging (pronounced oxidative susceptibility—Nrf2 absence) in the myocardium remains elusive. Thus, the purpose of our study was to determine the effect of chronic endurance exercise-induced cardiac adaptation in aged mice with and without Nrf2. Age-matched WT and Nrf2-null mice (Nrf2−/−) (>22 months) were subjected to 6 weeks chronic endurance exercise (25 meter/min, 12% grade). The myocardial redox status was assessed by expression of antioxidant defense genes and proteins along with immunochemical detection of DMPO-radical adduct, GSH-NEM, and total ubiquitination. Cardiac functions were assessed by echocardiography and electrocardiogram. At sedentary state, loss of Nrf2 resulted in significant downregulation of antioxidant gene expression (Nqo1, Ho1, Gclm, Cat, and Gst-α) with decreased GSH-NEM immuno-fluorescence signals. While Nrf2−/− mice subjected to CEE showed an either similar or more pronounced reduction in the transcript levels of Gclc, Nqo1, Gsr, and Gst-α in relation to WT littermates. In addition, the hearts of Nrf2−/− on CEE showed a substantial reduction in specific antioxidant proteins, G6PD and CAT along with decreased GSH, a pronounced increase in DMPO-adduct and the total ubiquitination levels. Further, CEE resulted in a significant upregulation of hypertrophy genes (Anf, Bnf, and β-Mhc) (p < 0.05) in the Nrf2−/− hearts in relation to WT mice. Moreover, the aged Nrf2−/− mice exhibited a higher degree of cardiac remodeling in association with a significant decrease in fractional

Transgenic expression of cyclooxygenase-2 (COX2) causes premature aging phenotypes in mice.

PubMed

Kim, Joohwee; Vaish, Vivek; Feng, Mingxiao; Field, Kevin; Chatzistamou, Ioulia; Shim, Minsub

2016-10-07

Cyclooxygenase (COX) is a key enzyme in the biosynthesis of prostanoids, lipid signaling molecules that regulate various physiological processes. COX2, one of the isoforms of COX, is highly inducible in response to a wide variety of cellular and environmental stresses. Increased COX2 expression is thought to play a role in the pathogenesis of many age-related diseases. COX2 expression is also reported to be increased in the tissues of aged humans and mice, which suggests the involvement of COX2 in the aging process. However, it is not clear whether the increased COX2 expression is causal to or a result of aging. We have now addressed this question by creating an inducible COX2 transgenic mouse model. Here we show that post-natal expression of COX2 led to a panel of aging-related phenotypes. The expression of p16, p53, and phospho-H2AX was increased in the tissues of COX2 transgenic mice. Additionally, adult mouse lung fibroblasts from COX2 transgenic mice exhibited increased expression of the senescence-associated β-galactosidase. Our study reveals that the increased COX2 expression has an impact on the aging process and suggests that modulation of COX2 and its downstream signaling may be an approach for intervention of age-related disorders.

Haploinsufficiency of myostatin protects against aging-related declines in muscle function and enhances the longevity of mice.

PubMed

Mendias, Christopher L; Bakhurin, Konstantin I; Gumucio, Jonathan P; Shallal-Ayzin, Mark V; Davis, Carol S; Faulkner, John A

2015-08-01

The molecular mechanisms behind aging-related declines in muscle function are not well understood, but the growth factor myostatin (MSTN) appears to play an important role in this process. Additionally, epidemiological studies have identified a positive correlation between skeletal muscle mass and longevity. Given the role of myostatin in regulating muscle size, and the correlation between muscle mass and longevity, we tested the hypotheses that the deficiency of myostatin would protect oldest-old mice (28-30 months old) from an aging-related loss in muscle size and contractility, and would extend the maximum lifespan of mice. We found that MSTN(+/-) and MSTN(-/-) mice were protected from aging-related declines in muscle mass and contractility. While no differences were detected between MSTN(+/+) and MSTN(-/-) mice, MSTN(+/-) mice had an approximately 15% increase in maximal lifespan. These results suggest that targeting myostatin may protect against aging-related changes in skeletal muscle and contribute to enhanced longevity. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Effects of Grape Skin Extract on Age-Related Mitochondrial Dysfunction, Memory and Life Span in C57BL/6J Mice.

PubMed

Asseburg, Heike; Schäfer, Carmina; Müller, Madeleine; Hagl, Stephanie; Pohland, Maximilian; Berressem, Dirk; Borchiellini, Marta; Plank, Christina; Eckert, Gunter P

2016-09-01

Dementia contributes substantially to the burden of disability experienced at old age, and mitochondrial dysfunction (MD) was identified as common final pathway in brain aging and Alzheimer's disease. Due to its early appearance, MD is a promising target for nutritional prevention strategies and polyphenols as potential neurohormetic inducers may be strong neuroprotective candidates. This study aimed to investigate the effects of a polyphenol-rich grape skin extract (PGE) on age-related dysfunctions of brain mitochondria, memory, life span and potential hormetic pathways in C57BL/6J mice. PGE was administered at a dose of 200 mg/kg body weight/d in a 3-week short-term, 6-month long-term and life-long study. MD in the brains of aged mice (19-22 months old) compared to young mice (3 months old) was demonstrated by lower ATP levels and by impaired mitochondrial respiratory complex activity (except for mice treated with antioxidant-depleted food pellets). Long-term PGE feeding partly enhanced brain mitochondrial respiration with only minor beneficial effect on brain ATP levels and memory of aged mice. Life-long PGE feeding led to a transient but significant shift of survival curve toward higher survival rates but without effect on the overall survival. The moderate effects of PGE were associated with elevated SIRT1 but not SIRT3 mRNA expressions in brain and liver tissue. The beneficial effects of the grape extract may have been influenced by the profile of bioavailable polyphenols and the starting point of interventions.

Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice

PubMed Central

Wheelan, Nicola; Webster, Scott P.; Kenyon, Christopher J.; Caughey, Sarah; Walker, Brian R.; Holmes, Megan C.; Seckl, Jonathan R.; Yau, Joyce L.W.

2015-01-01

High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. PMID:25497454

Survival of irradiated recipient mice after transplantation of bone marrow from young, old and "early aging" mice.

PubMed

Guest, Ian; Ilic, Zoran; Scrable, Heidi; Sell, Stewart

2015-12-01

Bone marrow transplantation is used to examine survival, hematopoietic stem cell function and pathology in recipients of young and old wild type bone marrow derived stem cells (BMDSCs) as well as cells from p53-based models of premature aging. There is no difference in the long term survival of recipients of 8 week-old p53+/m donor cells compared to recipients of 8 week-old wild-type (WT) donor cells (70 weeks) or of recipients of 16-18 weeks-old donor cells from either p53+/m or WT mice. There is shorter survival in recipients of older versus younger WT donor bone marrow, but the difference is only significant when comparing 8 and 18 week-old donors. In the p44-based model, short term survival/engraftment is significantly reduced in recipients of 11 month-old p44 donor cells compared to 4 week-old p44 or wild type donor cells of either age; mid-life survival at 40 weeks is also significantly less in recipients of p44 cells. BMDSCs are readily detectable within recipient bone marrow, lymph node, intestinal villi and liver sinusoids, but not in epithelial derived cells. These results indicate that recipients of young BMDSCs may survive longer than recipients of old bone marrow, but the difference is marginal at best.

Membrane and functional characterization of lymphoid and macrophage populations of Peyer's patches from adult and aged mice.

PubMed Central

Vĕtvicka, V; Tlaskalová-Hogenová, H; Fornůsek, L; Ríhová, B; Holán, V

1987-01-01

Properties of macrophages isolated from Peyer's patches were compared with properties of peritoneal macrophages. We found a very low expression of all types of Fc receptors as well as a low expression of Ia antigens on Peyer's patch macrophages. No substantial changes in the levels of FcR and Ia antigen expression were found during the process of ageing. The investigation of phagocytic activity showed the activated state of Peyer's patch macrophages. Comparing the surface markers of lymphocytes obtained from Peyer's patches of mice of different ages, we found no differences in the numbers of sIg+, Thy-+ or L3T4+ lymphocytes. The numbers of FcR+ and Lyt 2.2+ lymphocytes decreased markedly with age. PMID:3477526

Obesity-induced oxidative stress, accelerated functional decline with age and increased mortality in mice

PubMed Central

Zhang, Yiqiang; Fischer, Kathleen E.; Soto, Vanessa; Liu, Yuhong; Sosnowska, Danuta; Richardson, Arlan; Salmon, Adam B.

2015-01-01

Obesity is a serious chronic disease that increases the risk of numerous co-morbidities including metabolic syndrome, cardiovascular disease and cancer as well as increases risk of mortality leading some to suggest this represents accelerated aging. Obesity is associated with significant increases in oxidative stress in vivo and, despite the well-explored relationship between oxidative stress and aging, the role this plays in the increased mortality of obese subjects remains an unanswered question. Here, we addressed this by undertaking a comprehensive, longitudinal study of a group of high fat-fed obese mice and assessed both their changes in oxidative stress and in their performance in physiological assays known to decline with aging. In female C57BL/6J mice fed a high-fat diet starting in adulthood, mortality was significantly increased in high fat-fed mice as was oxidative damage in vivo. High fat-feeding significantly accelerated the decline in performance in several assays, including activity, gait, and rotarod. However, we also found that obesity had little effect on other markers and actually improved performance in grip strength, a marker of muscular function. Together, this first comprehensive assessment of longitudinal functional changes in high fat-fed mice suggests that obesity may induce segmental acceleration of some of the aging process. PMID:25558793

Effect of Sex Differences on Brain Mitochondrial Function and Its Suppression by Ovariectomy and in Aged Mice.

PubMed

Gaignard, Pauline; Savouroux, Stéphane; Liere, Philippe; Pianos, Antoine; Thérond, Patrice; Schumacher, Michael; Slama, Abdelhamid; Guennoun, Rachida

2015-08-01

Sex steroids regulate brain function in both normal and pathological states. Mitochondria are an essential target of steroids, as demonstrated by the experimental administration of 17β-estradiol or progesterone (PROG) to ovariectomized female rodents, but the influence of endogenous sex steroids remains understudied. To address this issue, mitochondrial oxidative stress, the oxidative phosphorylation system, and brain steroid levels were analyzed under 3 different experimental sets of endocrine conditions. The first set was designed to study steroid-mediated sex differences in young male and female mice, intact and after gonadectomy. The second set concerned young female mice at 3 time points of the estrous cycle in order to analyze the influence of transient variations in steroid levels. The third set involved the evaluation of the effects of a permanent decrease in gonadal steroids in aged male and female mice. Our results show that young adult females have lower oxidative stress and a higher reduced nicotinamide adenine dinucleotide (NADH)-linked respiration rate, which is related to a higher pyruvate dehydrogenase complex activity as compared with young adult males. This sex difference did not depend on phases of the estrous cycle, was suppressed by ovariectomy but not by orchidectomy, and no longer existed in aged mice. Concomitant analysis of brain steroids showed that pregnenolone and PROG brain levels were higher in females during the reproductive period than in males and decreased with aging in females. These findings suggest that the major male/female differences in brain pregnenolone and PROG levels may contribute to the sex differences observed in brain mitochondrial function.

A Lack of Ovarian Function Increases Neuroinflammation in Aged Mice

PubMed Central

Benedusi, Valeria; Meda, Clara; Della Torre, Sara; Monteleone, Giuseppina; Vegeto, Elisabetta

2012-01-01

Although several lines of evidence have indicated that menopause is associated with increased susceptibility to neurological disorders, the mechanisms involved in this phenomenon remain to be elucidated. Because neuroinflammation is a common feature of a number of brain diseases, we hypothesized that the cessation of ovarian functions and the consequent decrease in estrogen receptor (ER)-mediated antiinflammatory activity may represent a trigger for postmenopausal brain dysfunctions. The aim of the present study was to investigate the effects of aging and surgical menopause on the activity of ER in neuroinflammation. The present study shows that ER genes are expressed in the hippocampus, but ER transcriptional activity decreases significantly beginning at 12 months of age in intact and ovariectomized mice. With ovariectomy, we observe an age-dependent accumulation of mRNA encoding inflammatory mediators (e.g. TNFα, IL1β, and macrophage inflammatory protein-2) and changes in the morphology of astroglia and microglia. In addition, we show that aging itself is coupled with an exaggerated response to acute inflammatory stimuli with a major accumulation of TNFα, IL1β, macrophage inflammatory protein-2, and macrophage chemoattractant protein-1 mRNA in response to lipopolysaccharide administration. The response to acute inflammatory stimuli appears to be differentially modulated by the duration of hormone deprivation in 12-month-old mice. Taken together, the present results show that aging is associated with decreased ER activity, despite continuous ER synthesis, and that age-dependent neuroinflammation is strongly influenced by hormone deprivation. PMID:22492304

Protective effect of atorvastatin on d-galactose-induced aging model in mice.

PubMed

Kaviani, Elham; Rahmani, Mohammadreza; Kaeidi, Ayat; Shamsizadeh, Ali; Allahtavakoli, Mohamad; Mozafari, Nazanin; Fatemi, Iman

2017-09-15

Atorvastatin (Ator), competitive inhibitors of 3-hydroxymethyl-3-glutaryl-coenzyme-A reductase, is a cholesterol lowering drug. Ator has been shown to have neuroprotective, antioxidant and anti-inflammatory properties making that a potential candidate for the treatment of central nervous system (CNS) disorders. Here we assessed the effect of Ator on the d-galactose (d-gal)-induced aging in mice. For this purpose, Ator (0.1 and 1mg/kg/p.o.), was administrated daily in d-gal-received (500mg/kg/p.o.) mice model of aging for six weeks. Anxiety-like behaviors and cognitive functions were evaluated by the elevated plus-maze and novel object recognition tasks, respectively. Physical power was assessed by forced swimming capacity test. Animals brains were analyzed for the superoxide dismutase (SOD) and brain-derived neurotrophic factor (BDNF). We found that Ator decreases the anxiety-like behaviors in d-gal-treated mice. Also, our behavioral tests showed that Ator reverses the d-gal induced learning and memory impairment. Furthermore, we found that Ator increases the physical power of d-gal-treated mice. Our results indicated that the neuroprotective effect of Ator on d-gal induced neurotoxicity is mediated, at least in part, by an increase in the SOD and BDNF levels. The results of present study suggest that Ator could be used as a novel therapeutic strategy for the treatment of age-related conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Ketogenic Diet Reduces Midlife Mortality and Improves Memory in Aging Mice.

PubMed

Newman, John C; Covarrubias, Anthony J; Zhao, Minghao; Yu, Xinxing; Gut, Philipp; Ng, Che-Ping; Huang, Yu; Haldar, Saptarsi; Verdin, Eric

2017-09-05

Ketogenic diets recapitulate certain metabolic aspects of dietary restriction such as reliance on fatty acid metabolism and production of ketone bodies. We investigated whether an isoprotein ketogenic diet (KD) might, like dietary restriction, affect longevity and healthspan in C57BL/6 male mice. We find that Cyclic KD, KD alternated weekly with the Control diet to prevent obesity, reduces midlife mortality but does not affect maximum lifespan. A non-ketogenic high-fat diet (HF) fed similarly may have an intermediate effect on mortality. Cyclic KD improves memory performance in old age, while modestly improving composite healthspan measures. Gene expression analysis identifies downregulation of insulin, protein synthesis, and fatty acid synthesis pathways as mechanisms common to KD and HF. However, upregulation of PPARα target genes is unique to KD, consistent across tissues, and preserved in old age. In all, we show that a non-obesogenic ketogenic diet improves survival, memory, and healthspan in aging mice. Published by Elsevier Inc.

The mouse age phenome knowledgebase and disease-specific inter-species age mapping.

PubMed

Geifman, Nophar; Rubin, Eitan

2013-01-01

Similarities between mice and humans lead to generation of many mouse models of human disease. However, differences between the species often result in mice being unreliable as preclinical models for human disease. One difference that might play a role in lowering the predictivity of mice models to human diseases is age. Despite the important role age plays in medicine, it is too often considered only casually when considering mouse models. We developed the mouse-Age Phenotype Knowledgebase, which holds knowledge about age-related phenotypic patterns in mice. The knowledgebase was extensively populated with literature-derived data using text mining techniques. We then mapped between ages in humans and mice by comparing the age distribution pattern for 887 diseases in both species. The knowledgebase was populated with over 9800 instances generated by a text-mining pipeline. The quality of the data was manually evaluated, and was found to be of high accuracy (estimated precision >86%). Furthermore, grouping together diseases that share similar age patterns in mice resulted in clusters that mirror actual biomedical knowledge. Using these data, we matched age distribution patterns in mice and in humans, allowing for age differences by shifting either of the patterns. High correlation (r(2)>0.5) was found for 223 diseases. The results clearly indicate a difference in the age mapping between different diseases: age 30 years in human is mapped to 120 days in mice for Leukemia, but to 295 days for Anemia. Based on these results we generated a mice-to-human age map which is publicly available. We present here the development of the mouse-APK, its population with literature-derived data and its use to map ages in mice and human for 223 diseases. These results present a further step made to bridging the gap between humans and mice in biomedical research.

Coffee consumption in aged mice increases energy production and decreases hepatic mTOR levels.

PubMed

Takahashi, Keita; Yanai, Shuichi; Shimokado, Kentaro; Ishigami, Akihito

2017-06-01

Coffee, one of the world's most consumed beverages, has many benefits. Some studies have reported the effects of coffee on aging. The aim of this study was to investigate the locomotor activity, energy metabolism, and lipid metabolism of aged (20-mo-old) mice given coffee. Aged C57 BL/6 NCr mice were divided into three groups: controls that were not given coffee (n = 9), a group that received 0.1% caffeinated coffee (n = 9), and a group that received 0.1% decaffeinated coffee (n = 9). This regimen continued for 17 wk until mice reached the age of 24 mo. Regular and decaffeinated coffee consumption decreased plasma-free fatty acid levels, increased hepatic adenosine triphosphate content, and decreased total mammalian target of rapamycin (mTOR) and phosphorylated mTOR (p-mTOR) protein content in the liver. However, no differences were found in the protein or activity levels of Akt, adenosine monophosphate-activated protein kinase (AMPK), p70 S6 kinase, or sterol regulatory element-binding protein 1, proteins that are upstream or downstream of the mTOR complex 1 (mTORC1)-related pathways. Regular coffee consumption increased food and water intake, locomotor activity, the volume of carbon dioxide production, and the respiration exchange ratio. Regular and decaffeinated coffee consumption decreased hepatic total mTOR and p-mTOR levels independently of Akt and AMPK pathways in aged mice. Because decreased mTORC1 activity is known to have antiaging effects, coffee consumption during old age may retard aging. Moreover, coffee consumption by the aged population had a positive effect on behavioral energy and lipid metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

Transient rapamycin treatment can increase lifespan and healthspan in middle-aged mice

PubMed Central

Bitto, Alessandro; Ito, Takashi K; Pineda, Victor V; LeTexier, Nicolas J; Huang, Heather Z; Sutlief, Elissa; Tung, Herman; Vizzini, Nicholas; Chen, Belle; Smith, Kaleb; Meza, Daniel; Yajima, Masanao; Beyer, Richard P; Kerr, Kathleen F; Davis, Daniel J; Gillespie, Catherine H; Snyder, Jessica M; Treuting, Piper M; Kaeberlein, Matt

2016-01-01

The FDA approved drug rapamycin increases lifespan in rodents and delays age-related dysfunction in rodents and humans. Nevertheless, important questions remain regarding the optimal dose, duration, and mechanisms of action in the context of healthy aging. Here we show that 3 months of rapamycin treatment is sufficient to increase life expectancy by up to 60% and improve measures of healthspan in middle-aged mice. This transient treatment is also associated with a remodeling of the microbiome, including dramatically increased prevalence of segmented filamentous bacteria in the small intestine. We also define a dose in female mice that does not extend lifespan, but is associated with a striking shift in cancer prevalence toward aggressive hematopoietic cancers and away from non-hematopoietic malignancies. These data suggest that a short-term rapamycin treatment late in life has persistent effects that can robustly delay aging, influence cancer prevalence, and modulate the microbiome. DOI: http://dx.doi.org/10.7554/eLife.16351.001 PMID:27549339

Immunization of Aged Mice with a Pneumococcal Conjugate Vaccine Combined with an Unmethylated CpG-Containing Oligodeoxynucleotide Restores Defective Immunoglobulin G Antipolysaccharide Responses and Specific CD4+-T-Cell Priming to Young Adult Levels

DTIC Science & Technology

2006-04-01

aged and young adult mice made comparable levels of proinflammatory cytokines in response to CpG-ODN, although cells from aged mice secreted higher...sepsis, is significantly elevated in the elderly relative to young adults (37, 60). Defective innate immunity including diminished neutrophil and...young adult recipients (15). Exposure to inflammatory cy- tokines in vivo could restore the defective CD4-T-cell function in aged mice (20). Pn

N-Acetylmannosamine improves sleep-wake quality in middle-aged mice: relevance to autonomic nervous function.

PubMed

Kuwahara, Masayoshi; Ito, Koichi; Hayakawa, Koji; Yagi, Shintaro; Shiota, Kunio

2015-01-01

Aging is associated with a variety of physiological changes originating peripherally and centrally, including within the autonomic nervous system. Sleep-wake disturbances constitute reliable hallmarks of aging in several animal species and humans. Recent studies have been interested in N-acetylmannosamine (ManNAc) a potential therapeutic agent for improving quality of life, as well as preventing age-related cognitive decline. In this study, ManNAc (5.0 mg/ml) was administered in the drinking water of middle-aged male C57BL/6J mice (55 weeks old) for 7 days. Mice were housed under a 12:12 h light:dark cycle at 23-24 °C. We evaluated bio-behavioral activity using electrocardiogram, body temperature and locomotor activity recorded by an implanted telemetry transmitter. To estimate sleep-wake profile, surface electroencephalogram and electromyogram leads connected to a telemetry transmitter were also implanted in mice. Autonomic nervous activity was evaluated using power spectral analysis of heart rate variability. ManNAc-treated mice spent more time in a wakeful state and less time in slow wave sleep during the dark phase. Parasympathetic nervous activity was increased following ManNAc treatment, then the sympatho-vagal balance was shifted predominance of parasympathetic nervous system. Furthermore, improvement in sleep-wake pattern was associated with increased parasympathetic nervous activity. These results suggest that ManNAc treatment can improve bio-behavioral activity and sleep-wake quality in middle-aged mice. This may have implications for improving sleep patterns in elderly humans. Copyright © 2014 Elsevier B.V. All rights reserved.

Influence of aging on the activity of mice Sca-1+CD31- cardiac stem cells.

PubMed

Wu, Qiong; Zhan, Jinxi; Pu, Shiming; Qin, Liu; Li, Yun; Zhou, Zuping

2017-01-03

Therapeutic application of cardiac resident stem/progenitor cells (CSC/CPCs) is limited due to decline of their regenerative potential with donor age. A variety of studies have shown that the cardiac aging was the problem of the stem cells, but little is known about the impact of age on the subgroups CSC/CPCs, the relationship between subgroups CSC/CPCs ageing and age-related dysfunction. Here, we studied Sca-1+CD31- subgroups of CSCs from younger(2~3months) and older(22~24months) age mice, biological differentiation was realized using specific mediums for 14 days to induce cardiomyocyte, smooth muscle cells or endothelial cells and immunostain analysis of differentiated cell resulting were done. Proliferation and cell cycle were measured by flow cytometry assay, then used microarray to dissect variability from younger and older mice. Although the number of CSCs was higher in older mice, the advanced age significantly reduced the differentiation ability into cardiac cell lineages and the proliferation ability. Transcriptional changes in Sca-1+CD31- subgroups of CSCs during aging are related to Vitamin B6 metabolism, circadian rhythm, Tyrosine metabolism, Complement and coagulation cascades. Taking together these results indicate that Cardiac resident stem/progenitor cells have significant differences in their proliferative, pluripotency and gene profiles and those differences are age depending.

[Effect of pineal peptide on parameters of the biological age and life span in mice].

PubMed

Anisimov, V N; Khavinson, V Kh; Zavarzina, N Iu; Zabezhinskiĭ, M A; Zimina, O A; Popovich, I G; Shtylik, A V; Arutiunian, A V; Oparina, T I; Prokopenko, V M

2001-01-01

Female CBA mice were injected with s.c. synthetic tetrapeptide Epithalon from a 6-month age until death. The drug failed to affect the body weight or food consumption, physical activity or behavioural parameters. However, it slowed down the age-related switching off of the estrus function, decreased body temperature, decelerated free redical processes, prolonged the mice life span with an accompanying drop in spontaneous tumour incidence.

Recombinant growth differentiation factor 11 influences short-term memory and enhances Sox2 expression in middle-aged mice.

PubMed

Zhang, Min; Jadavji, Nafisa M; Yoo, Hyung-Suk; Smith, Patrice D

2018-04-02

Previous evidence suggests that a significant decline in cognitive ability begins during middle-age and continues to deteriorate with increase in age. Recent work has demonstrated the potential rejuvenation impact of growth differentiation factor-11 (GDF-11) in aged mice. We carried out experiments to evaluate the impact of a single dose of recombinant (rGDF-11) on short-term visual and spatial memory in middle-aged male mice. On the novel object recognition task, we observed middle-aged mice treated rGDF-11 showed improved performance on the novel object recognition task. However, middle-aged mice did not show increased expression of phosphorylated-Smad2/3, a downstream effector of GDF-11. We noted however that the expression of the transcription factor, Sox2 was increased within the dentate gyrus. Our data suggest that a single injection of rGDF-11 contributes to improvements in cognitive function of middle-aged animals, which may be critical in the preservation of short-term memory capacity in old age. Copyright © 2017 Elsevier B.V. All rights reserved.

A Ser75-to-Asp phospho-mimicking mutation in Src accelerates ageing-related loss of retinal ganglion cells in mice.

PubMed

Kashiwagi, Kenji; Ito, Sadahiro; Maeda, Shuichiro; Kato, Goro

2017-12-01

Src knockout mice show no detectable abnormalities in central nervous system (CNS) post-mitotic neurons, likely reflecting functional compensation by other Src family kinases. Cdk1- or Cdk5-dependent Ser75 phosphorylation in the amino-terminal Unique domain of Src, which shares no homology with other Src family kinases, regulates the stability of active Src. To clarify the roles of Src Ser75 phosphorylation in CNS neurons, we established two types of mutant mice with mutations in Src: phospho-mimicking Ser75Asp (SD) and non-phosphorylatable Ser75Ala (SA). In ageing SD/SD mice, retinal ganglion cell (RGC) number in whole retinas was significantly lower than that in young SD/SD mice in the absence of inflammation and elevated intraocular pressure, resembling the pathogenesis of progressive optic neuropathy. By contrast, SA/SA mice and wild-type (WT) mice exhibited no age-related RGC loss. The age-related retinal RGC number reduction was greater in the peripheral rather than the mid-peripheral region of the retina in SD/SD mice. Furthermore, Rho-associated kinase activity in whole retinas of ageing SD/SD mice was significantly higher than that in young SD/SD mice. These results suggest that Src regulates RGC survival during ageing in a manner that depends on Ser75 phosphorylation.

Chronic intermittent exposure to ayahuasca during aging does not affect memory in mice.

PubMed

Correa-Netto, N F; Coelho, L S; Galfano, G S; Nishide, F; Tamura, F; Shimizu, M K; Santos, J G; Linardi, A

2017-06-05

The Quechua term ayahuasca refers to a beverage obtained from decoctions of the liana Banisteriopsis caapi with leaves of Psychotria viridis. The ritualistic use of ayahuasca is becoming a global phenomenon, with some individuals using this beverage throughout life, including in old age. Cognitive impairment is a common manifestation during aging. There are conflicting reports on the ability of some ayahuasca compounds to exert neuroprotective or neurotoxic effects that could improve or impair learning and memory. Animal models provide a relevant and accessible means of investigating the behavioral effects of ayahuasca without the environmental conditions associated with the ritualistic use of the beverage. In this study, we investigated the influence of chronic ayahuasca exposure throughout aging on the spatial reference and habituation memories of mice. Twenty-eight male c57bl/6 mice (6 months old) received ayahuasca or water (1.5 mL/kg, orally) twice a week for 12 months and were tested in the Morris water maze (MWM), open field and elevated plus maze (EPM) tasks before and after treatment. During aging, there was significant impairment in the evocation (but not acquisition) of spatial reference memory and in habituation to the open field. There was also a decrease in locomotor activity in the open field and EPM tests, whereas the anxiety parameters were unaltered. Ayahuasca treatment did not alter any of these parameters associated with aging. These findings indicate that chronic exposure to ayahuasca during aging did not affect memory in mice.

Chronic intermittent exposure to ayahuasca during aging does not affect memory in mice

PubMed Central

Correa-Netto, N.F.; Coelho, L.S.; Galfano, G.S.; Nishide, F.; Tamura, F.; Shimizu, M.K.; Santos, J.G.; Linardi, A.

2017-01-01

The Quechua term ayahuasca refers to a beverage obtained from decoctions of the liana Banisteriopsis caapi with leaves of Psychotria viridis. The ritualistic use of ayahuasca is becoming a global phenomenon, with some individuals using this beverage throughout life, including in old age. Cognitive impairment is a common manifestation during aging. There are conflicting reports on the ability of some ayahuasca compounds to exert neuroprotective or neurotoxic effects that could improve or impair learning and memory. Animal models provide a relevant and accessible means of investigating the behavioral effects of ayahuasca without the environmental conditions associated with the ritualistic use of the beverage. In this study, we investigated the influence of chronic ayahuasca exposure throughout aging on the spatial reference and habituation memories of mice. Twenty-eight male c57bl/6 mice (6 months old) received ayahuasca or water (1.5 mL/kg, orally) twice a week for 12 months and were tested in the Morris water maze (MWM), open field and elevated plus maze (EPM) tasks before and after treatment. During aging, there was significant impairment in the evocation (but not acquisition) of spatial reference memory and in habituation to the open field. There was also a decrease in locomotor activity in the open field and EPM tests, whereas the anxiety parameters were unaltered. Ayahuasca treatment did not alter any of these parameters associated with aging. These findings indicate that chronic exposure to ayahuasca during aging did not affect memory in mice. PMID:28591380

Parvalbumin-expressing ependymal cells in rostral lateral ventricle wall adhesions contribute to aging-related ventricle stenosis in mice.

PubMed

Filice, Federica; Celio, Marco R; Babalian, Alexandre; Blum, Walter; Szabolcsi, Viktoria

2017-10-15

Aging-associated ependymal-cell pathologies can manifest as ventricular gliosis, ventricle enlargement, or ventricle stenosis. Ventricle stenosis and fusion of the lateral ventricle (LV) walls is associated with a massive decline of the proliferative capacities of the stem cell niche in the affected subventricular zone (SVZ) in aging mice. We examined the brains of adult C57BL/6 mice and found that ependymal cells located in the adhesions of the medial and lateral walls of the rostral LVs upregulated parvalbumin (PV) and displayed reactive phenotype, similarly to injury-reactive ependymal cells. However, PV+ ependymal cells in the LV-wall adhesions, unlike injury-reactive ones, did not express glial fibrillary acidic protein. S100B+/PV+ ependymal cells found in younger mice diminished in the LV-wall adhesions throughout aging. We found that periventricular PV-immunofluorescence showed positive correlation to the grade of LV stenosis in nonaged mice (<10-month-old), and that the extent of LV-wall adhesions and LV stenosis was significantly lower in mid-aged (>10-month-old) PV-knock out (PV-KO) mice. This suggests an involvement of PV+ ependymal cells in aging-associated ventricle stenosis. Additionally, we observed a time-shift in microglial activation in the LV-wall adhesions between age-grouped PV-KO and wild-type mice, suggesting a delay in microglial activation when PV is absent from ependymal cells. Our findings implicate that compromised ependymal cells of the adhering ependymal layers upregulate PV and display phenotype shift to "reactive" ependymal cells in aging-related ventricle stenosis; moreover, they also contribute to the progression of LV-wall fusion associated with a decline of the affected SVZ-stem cell niche in aged mice. © 2017 Wiley Periodicals, Inc.

Parity History Determines a Systemic Inflammatory Response to Spread of Ovarian Cancer in Naturally Aged Mice.

PubMed

Urzua, Ulises; Chacon, Carlos; Lizama, Luis; Sarmiento, Sebastián; Villalobos, Pía; Kroxato, Belén; Marcelain, Katherine; Gonzalez, María-Julieta

2017-10-01

Aging intersects with reproductive senescence in women by promoting a systemic low-grade chronic inflammation that predisposes women to several diseases including ovarian cancer (OC). OC risk at menopause is significantly modified by parity records during prior fertile life. To date, the combined effects of age and parity on the systemic inflammation markers that are particularly relevant to OC initiation and progression at menopause remain largely unknown. Herein, we profiled a panel of circulating cytokines in multiparous versus virgin C57BL/6 female mice at peri-estropausal age and investigated how cytokine levels were modulated by intraperitoneal tumor induction in a syngeneic immunocompetent OC mouse model. Serum FSH, LH and TSH levels increased with age in both groups while prolactin (PRL) was lower in multiparous respect to virgin mice, a finding previously observed in parous women. Serum CCL2, IL-10, IL-5, IL-4, TNF-α, IL1-β and IL-12p70 levels increased with age irrespective of parity status, but were specifically reduced following OC tumor induction only in multiparous mice. Animals developed hemorrhagic ascites and tumor implants in the omental fat band and other intraperitoneal organs by 12 weeks after induction, with multiparous mice showing a significantly extended survival. We conclude that previous parity history counteracts aging-associated systemic inflammation possibly by reducing the immunosuppression that typically allows tumor spread. Results suggest a partial impairment of the M2 shift in tumor-associated macrophages as well as decreased stimulation of regulatory B-cells in aged mice. This long term, tumor-concurrent effect of parity on inflammation markers at menopause would be a contributing factor leading to decreased OC risk.

Parity History Determines a Systemic Inflammatory Response to Spread of Ovarian Cancer in Naturally Aged Mice

PubMed Central

Urzua, Ulises; Chacon, Carlos; Lizama, Luis; Sarmiento, Sebastián; Villalobos, Pía; Kroxato, Belén; Marcelain, Katherine; Gonzalez, María-Julieta

2017-01-01

Aging intersects with reproductive senescence in women by promoting a systemic low-grade chronic inflammation that predisposes women to several diseases including ovarian cancer (OC). OC risk at menopause is significantly modified by parity records during prior fertile life. To date, the combined effects of age and parity on the systemic inflammation markers that are particularly relevant to OC initiation and progression at menopause remain largely unknown. Herein, we profiled a panel of circulating cytokines in multiparous versus virgin C57BL/6 female mice at peri-estropausal age and investigated how cytokine levels were modulated by intraperitoneal tumor induction in a syngeneic immunocompetent OC mouse model. Serum FSH, LH and TSH levels increased with age in both groups while prolactin (PRL) was lower in multiparous respect to virgin mice, a finding previously observed in parous women. Serum CCL2, IL-10, IL-5, IL-4, TNF-α, IL1-β and IL-12p70 levels increased with age irrespective of parity status, but were specifically reduced following OC tumor induction only in multiparous mice. Animals developed hemorrhagic ascites and tumor implants in the omental fat band and other intraperitoneal organs by 12 weeks after induction, with multiparous mice showing a significantly extended survival. We conclude that previous parity history counteracts aging-associated systemic inflammation possibly by reducing the immunosuppression that typically allows tumor spread. Results suggest a partial impairment of the M2 shift in tumor-associated macrophages as well as decreased stimulation of regulatory B-cells in aged mice. This long term, tumor-concurrent effect of parity on inflammation markers at menopause would be a contributing factor leading to decreased OC risk. PMID:28966800

Protein catabolism in cultures of hepatocytes derived from mice of various ages.

PubMed

Burrows, R B; Davison, P F

1982-05-01

The degradation of pulse-labeled protein was measured in cultures of hepatocytes derived from mice of 3--4, 15--16, and 28 months of age. The rates of protein degradation were determined in culture media with varying amino acid, insulin, and glucagon concentrations. No differences with age were seen. Also no difference with age was detected in the lysosomal degradation of 125I-labeled asialofetuin.

Biochemical alterations during the obese-aging process in female and male monosodium glutamate (MSG)-treated mice.

PubMed

Hernández-Bautista, René J; Alarcón-Aguilar, Francisco J; Del C Escobar-Villanueva, María; Almanza-Pérez, Julio C; Merino-Aguilar, Héctor; Fainstein, Mina Konigsberg; López-Diazguerrero, Norma E

2014-06-27

Obesity, from children to the elderly, has increased in the world at an alarming rate over the past three decades, implying long-term detrimental consequences for individual's health. Obesity and aging are known to be risk factors for metabolic disorder development, insulin resistance and inflammation, but their relationship is not fully understood. Prevention and appropriate therapies for metabolic disorders and physical disabilities in older adults have become a major public health challenge. Hence, the aim of this study was to evaluate inflammation markers, biochemical parameters and glucose homeostasis during the obese-aging process, to understand the relationship between obesity and health span during the lifetime. In order to do this, the monosodium glutamate (MSG) obesity mice model was used, and data were evaluated at 4, 8, 12, 16 and 20 months in both female and male mice. Our results showed that obesity was a major factor contributing to premature alterations in MSG-treated mice metabolism; however, at older ages, obesity effects were attenuated and MSG-mice became more similar to normal mice. At a younger age (four months old), the Lee index, triglycerides, total cholesterol, TNF-α and transaminases levels increased; while adiponectin decreased and glucose tolerance and insulin sensitivity levels were remarkably altered. However, from 16 months old-on, the Lee index and TNF-α levels diminished significantly, while adiponectin increased, and glucose and insulin homeostasis was recovered. In summary, MSG-treated obese mice showed metabolic changes and differential susceptibility by gender throughout life and during the aging process. Understanding metabolic differences between genders during the lifespan will allow the discovery of specific preventive treatment strategies for chronic diseases and functional decline.

Biochemical Alterations during the Obese-Aging Process in Female and Male Monosodium Glutamate (MSG)-Treated Mice

PubMed Central

Hernández-Bautista, René J.; Alarcón-Aguilar, Francisco J.; Escobar-Villanueva, María Del C.; Almanza-Pérez, Julio C.; Merino-Aguilar, Héctor; Konigsberg Fainstein, Mina; López-Diazguerrero, Norma E.

2014-01-01

Obesity, from children to the elderly, has increased in the world at an alarming rate over the past three decades, implying long-term detrimental consequences for individual’s health. Obesity and aging are known to be risk factors for metabolic disorder development, insulin resistance and inflammation, but their relationship is not fully understood. Prevention and appropriate therapies for metabolic disorders and physical disabilities in older adults have become a major public health challenge. Hence, the aim of this study was to evaluate inflammation markers, biochemical parameters and glucose homeostasis during the obese-aging process, to understand the relationship between obesity and health span during the lifetime. In order to do this, the monosodium glutamate (MSG) obesity mice model was used, and data were evaluated at 4, 8, 12, 16 and 20 months in both female and male mice. Our results showed that obesity was a major factor contributing to premature alterations in MSG-treated mice metabolism; however, at older ages, obesity effects were attenuated and MSG-mice became more similar to normal mice. At a younger age (four months old), the Lee index, triglycerides, total cholesterol, TNF-α and transaminases levels increased; while adiponectin decreased and glucose tolerance and insulin sensitivity levels were remarkably altered. However, from 16 months old-on, the Lee index and TNF-α levels diminished significantly, while adiponectin increased, and glucose and insulin homeostasis was recovered. In summary, MSG-treated obese mice showed metabolic changes and differential susceptibility by gender throughout life and during the aging process. Understanding metabolic differences between genders during the lifespan will allow the discovery of specific preventive treatment strategies for chronic diseases and functional decline. PMID:24979131

Partial correction of the dwarf phenotype by non-viral transfer of the growth hormone gene in mice: Treatment age is critical.

PubMed

Higuti, Eliza; Cecchi, Cláudia R; Oliveira, Nélio A J; Lima, Eliana R; Vieira, Daniel P; Aagaard, Lars; Jensen, Thomas G; Jorge, Alexander A L; Bartolini, Paolo; Peroni, Cibele N

2016-02-01

Non-viral transfer of the growth hormone gene to different muscles of immunodeficient dwarf (lit/scid) mice is under study with the objective of improving phenotypic correction via this particular gene therapy approach. Plasmid DNA was administered into the exposed quadriceps or non-exposed tibialis cranialis muscle of lit/scid mice followed by electroporation, monitoring several growth parameters. In a 6-month bioassay, 50μg DNA were injected three times into the quadriceps muscle of 80-day old mice. A 50% weight increase, with a catch-up growth of 21%, together with a 16% increase for nose-to-tail and tail lengths (catch-up=19-21%) and a 24-28% increase for femur length (catch-up=53-60%), were obtained. mIGF1 serum levels were ~7-fold higher than the basal levels for untreated mice, but still ~2-fold lower than in non-dwarf scid mice. Since treatment age was found to be particularly important in a second bioassay utilizing 40-day old mice, these pubertal mice were compared in a third bioassay with adult (80-day old) mice, all treated twice with 50μg DNA injected into each tibialis cranialis muscle, via a less invasive approach. mIGF1 concentrations at the same level as co-aged scid mice were obtained 15days after administration in pubertal mice. Catch-up growth, based on femur length (77%), nose-to-tail (36%) and tail length (39%) increases was 40 to 95% higher than those obtained upon treating adult mice. These data pave the way for the development of more effective pre-clinical assays in pubertal dwarf mice for the treatment of GH deficiency via plasmid-DNA muscular administration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Advancing age increases sperm chromatin damage and impairs fertility in peroxiredoxin 6 null mice

PubMed Central

Ozkosem, Burak; Feinstein, Sheldon I.; Fisher, Aron B.; O’Flaherty, Cristian

2015-01-01

Due to socioeconomic factors, more couples are choosing to delay conception than ever. Increasing average maternal and paternal age in developed countries over the past 40 years has raised the question of how aging affects reproductive success of males and females. Since oxidative stress in the male reproductive tract increases with age, we investigated the impact of advanced paternal age on the integrity of sperm nucleus and reproductive success of males by using a Prdx6−/− mouse model. We compared sperm motility, cytoplasmic droplet retention sperm chromatin quality and reproductive outcomes of young (2-month-old), adult (8-month-old), and old (20-month-old) Prdx6−/− males with their age-matched wild type (WT) controls. Absence of PRDX6 caused age-dependent impairment of sperm motility and sperm maturation and increased sperm DNA fragmentation and oxidation as well as decreased sperm DNA compaction and protamination. Litter size, total number of litters and total number of pups per male were significantly lower in Prdx6−/− males compared to WT controls. These abnormal reproductive outcomes were severely affected by age in Prdx6−/− males. In conclusion, the advanced paternal age affects sperm chromatin integrity and fertility more severely in the absence of PRDX6, suggesting a protective role of PRDX6 in age-associated decline in the sperm quality and fertility in mice. PMID:25796034

Advancing age increases sperm chromatin damage and impairs fertility in peroxiredoxin 6 null mice.

PubMed

Ozkosem, Burak; Feinstein, Sheldon I; Fisher, Aron B; O'Flaherty, Cristian

2015-08-01

Due to socioeconomic factors, more couples are choosing to delay conception than ever. Increasing average maternal and paternal age in developed countries over the past 40 years has raised the question of how aging affects reproductive success of males and females. Since oxidative stress in the male reproductive tract increases with age, we investigated the impact of advanced paternal age on the integrity of sperm nucleus and reproductive success of males by using a Prdx6(-/-) mouse model. We compared sperm motility, cytoplasmic droplet retention sperm chromatin quality and reproductive outcomes of young (2-month-old), adult (8-month-old), and old (20-month-old) Prdx6(-/-) males with their age-matched wild type (WT) controls. Absence of PRDX6 caused age-dependent impairment of sperm motility and sperm maturation and increased sperm DNA fragmentation and oxidation as well as decreased sperm DNA compaction and protamination. Litter size, total number of litters and total number of pups per male were significantly lower in Prdx6(-/-) males compared to WT controls. These abnormal reproductive outcomes were severely affected by age in Prdx6(-/-) males. In conclusion, the advanced paternal age affects sperm chromatin integrity and fertility more severely in the absence of PRDX6, suggesting a protective role of PRDX6 in age-associated decline in the sperm quality and fertility in mice. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Effects of aging on the immunopathological response to sepsis

PubMed Central

Turnbull, Isaiah R.; Clark, Andrew T.; Stromberg, Paul E.; Dixon, David J.; Woolsey, Cheryl A.; Davis, Christopher G.; Hotchkiss, Richard S.; Buchman, Timothy G.; Coopersmith, Craig M.

2009-01-01

Objective Aging is associated with increased inflammation following sepsis. The purpose of this study was to determine if this represents a fundamental age-based difference in the host response or is secondary to the increased mortality seen in aged hosts. Design Prospective, randomized controlled study. Setting Animal laboratory in a university medical center. Subjects Young (6–12 week) and aged (20–24 month) FVB/N mice. Interventions Mice were subjected to 2×25 or 1×30 cecal ligation and puncture (CLP). Measurements and Main Results Survival was similar in young mice subjected to 2×25 CLP and aged mice subjected to 1×30 CLP (p=0.15). Young mice subjected to 1×30 CLP had improved survival compared to both other groups (p<0.05). When injury was held constant but mortality was greater, both systemic and peritoneal levels of TNF-α, IL-6, IL-10 and MCP-1 were elevated 24 hours after CLP in aged animals compared to young animals (p<0.05). When mortality was similar but injury severity was different, there were no significant differences in systemic cytokines between aged mice and young mice. In contrast, peritoneal levels of TNF-α, IL-6, and IL-10 were higher in aged mice subjected to 1×30 CLP than young mice subjected to 2×25 CLP despite their similar mortalities (p<0.05). There were no significant differences in either bacteremia or peritoneal cultures when animals of different ages sustained similar injuries or had different injuries with similar mortalities. Conclusions Aged mice are more likely to die from sepsis than young mice when subjected to an equivalent insult, and this is associated with increases in both systemic and local inflammation. There is an exaggerated local but not systemic inflammatory response in aged mice compared to young mice when mortality is similar. This suggests that systemic processes that culminate in death may be age-independent, but the local inflammatory response may be greater with aging. PMID:19237912

Effects of aging on the immunopathologic response to sepsis.

PubMed

Turnbull, Isaiah R; Clark, Andrew T; Stromberg, Paul E; Dixon, David J; Woolsey, Cheryl A; Davis, Christopher G; Hotchkiss, Richard S; Buchman, Timothy G; Coopersmith, Craig M

2009-03-01

Aging is associated with increased inflammation following sepsis. The purpose of this study was to determine whether this represents a fundamental age-based difference in the host response or is secondary to the increased mortality seen in aged hosts. Prospective, randomized controlled study. Animal laboratory in a university medical center. Young (6-12 weeks) and aged (20-24 months) FVB/N mice. Mice were subjected to 2 x 25 or 1 x 30 cecal ligation and puncture (CLP). Survival was similar in young mice subjected to 2 x 25 CLP and aged mice subjected to 1 x 30 CLP (p = 0.15). Young mice subjected to 1 x 30 CLP had improved survival compared with the other groups (p < 0.05). When injury was held constant but mortality was greater, both systemic and peritoneal levels of tumor necrosis factor-alpha, interleukin (IL)-6, IL-10, and monocyte chemotactic protein-1 were elevated 24 hours after CLP in aged animals compared with young animals (p < 0.05). When mortality was similar but injury severity was different, there were no significant differences in systemic cytokines between aged mice and young mice. In contrast, peritoneal levels of tumor necrosis factor-alpha, IL-6, and IL-10 were higher in aged mice subjected to 1 x 30 CLP than young mice subjected to 2 x 25 CLP despite their similar mortalities (p < 0.05). There were no significant differences in either bacteremia or peritoneal cultures when animals of different ages sustained similar injuries or had different injuries with similar mortalities. Aged mice are more likely to die of sepsis than young mice when subjected to an equivalent insult, and this is associated with increases in both systemic and local inflammation. There is an exaggerated local but not systemic inflammatory response in aged mice compared with young mice when mortality is similar. This suggests that systemic processes that culminate in death may be age independent, but the local inflammatory response may be greater with aging.

The potent free radical scavenger alpha-lipoic acid improves memory in aged mice: putative relationship to NMDA receptor deficits.

PubMed

Stoll, S; Hartmann, H; Cohen, S A; Müller, W E

1993-12-01

alpha-Lipoic acid (alpha-LA) improved longer-term memory of aged female NMRI mice in the habituation in the open field test at a dose of 100 mg/kg body weight for 15 days. In a separate experiment, no such effect could be found for young mice. alpha-LA alleviated age-related NMDA receptor deficits (Bmax) without changing muscarinic, benzodiazepine, and alpha 2-adrenergic receptor deficits in aged mice. The carbachol-stimulated accumulation of inositol monophosphates was not changed by the treatment with alpha-LA. These results give tentative support to the hypothesis that alpha-LA improves memory in aged mice, probably by a partial compensation of NMDA receptor deficits. Possible modes of action of alpha-LA based on its free radical scavenger properties are discussed in relation to the membrane hypothesis of aging.

Lack of P4H-TM in mice results in age-related retinal and renal alterations.

PubMed

Leinonen, Henri; Rossi, Maarit; Salo, Antti M; Tiainen, Päivi; Hyvärinen, Jaana; Pitkänen, Marja; Sormunen, Raija; Miinalainen, Ilkka; Zhang, Chi; Soininen, Raija; Kivirikko, Kari I; Koskelainen, Ari; Tanila, Heikki; Myllyharju, Johanna; Koivunen, Peppi

2016-09-01

Age-related macular degeneration (AMD), affecting the retinal pigment epithelium (RPE), is the leading cause of blindness in middle-aged and older people in developed countries. Genetic and environmental risk factors have been identified, but no effective cure exists. Using a mouse model we show that a transmembrane prolyl 4-hydroxylase (P4H-TM), which participates in the oxygen-dependent regulation of the hypoxia-inducible factor (HIF), is a potential novel candidate gene for AMD. We show that P4h-tm had its highest expression levels in the mouse RPE and brain, heart, lung, skeletal muscle and kidney. P4h-tm -/- mice were fertile and had a normal life span. Lack of P4h-tm stabilized HIF-1α in cortical neurons under normoxia, while in hypoxia it increased the expression of certain HIF target genes in tissues with high endogenous P4h-tm expression levels more than in wild-type mice. Renal erythropoietin levels increased in P4h-tm -/- mice with aging, but the resulting ∼2-fold increase in erythropoietin serum levels did not lead to erythrocytosis. Instead, accumulation of lipid-containing lamellar bodies in renal tubuli was detected in P4h-tm -/- mice with aging, resulting in inflammation and fibrosis, and later glomerular sclerosis and albuminuria. Lack of P4h-tm was associated with retinal thinning, rosette-like infoldings and drusen-like structure accumulation in RPE with aging, as is characteristic of AMD. Photoreceptor recycling was compromised, and electroretinograms revealed functional impairment of the cone pathway in adult P4h-tm -/- mice and cone and rod deficiency in middle-aged mice. P4H-TM is therefore imperative for normal vision, and potentially a novel candidate for age-induced diseases, such as AMD. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pax6 interacts with Iba1 and shows age-associated alterations in brain of aging mice.

PubMed

Maurya, Shashank Kumar; Mishra, Rajnikant

2017-07-01

The Pax6, a transcriptional regulator and multifunctional protein, has been found critical for neurogenesis, neuro-degeneration, mental retardation, neuroendocrine tumors, glioblastoma and astrocytomas. The age-associated alteration in the expression of Pax6 in neuron and glia has also been observed in the immunologically privileged brain. Therefore, it is presumed that Pax6 may modulate brain immunity by activation of microglia either directly interacting with genes or proteins of microglia or indirectly though inflammation associated with neurodegeneration. This report describes evaluation of expression, co-localization and interactions of Pax6 with Ionized binding protein1 (Iba1) in brain of aging mice by Immunohistochemistry, Chromatin Immuno-precipitation (ChIP) and Co-immunoprecipitation (Co-IP), respectively. The co-localization of Pax6 with Iba1 was observed in the cerebellum, cerebral cortex, hippocampus, midbrain and olfactory lobe. The Pax6 and Iba1 also interact physically. The age-dependent alteration in their expression and co-localization were also observed in mice. Results indicate Pax6-dependent activities of Iba1 in the remodelling of microglia during immunological surveillance of the brain. Copyright © 2017 Elsevier B.V. All rights reserved.

Resistance to age-dependent thymic atrophy in long-lived mice that are deficient in pregnancy-associated plasma protein A

PubMed Central

Vallejo, Abbe N.; Michel, Joshua J.; Bale, Laurie K.; Lemster, Bonnie H.; Borghesi, Lisa; Conover, Cheryl A.

2009-01-01

Pregnancy-associated plasma protein A (PAPPA) is a metalloproteinase that controls the tissue availability of insulin-like growth factor (IGF). Homozygous deletion of PAPPA in mice leads to lifespan extension. Since immune function is an important determinant of individual fitness, we examined the natural immune ecology of PAPPA−/− mice and their wild-type littermates reared under specific pathogen-free condition with aging. Whereas wild-type mice exhibit classic age-dependent thymic atrophy, 18-month-old PAPPA−/− mice maintain discrete thymic cortex and medulla densely populated by CD4+CD8+ thymocytes that are capable of differentiating into single-positive CD4 and CD8 T cells. Old PAPPA−/− mice have high levels of T cell receptor excision circles, and have bone marrows enriched for subsets of thymus-seeding progenitors. PAPPA−/− mice have an overall larger pool of naive T cells, and also exhibit an age-dependent accumulation of CD44+CD43+ memory T cells similar to wild-type mice. However, CD43+ T cell subsets of old PAPPA−/− mice have significantly lower prevalence of 1B11 and S7, glycosylation isoforms known to inhibit T cell activation with normal aging. In bioassays of cell activation, splenic T cells of old PAPPA−/− mice have high levels of activation antigens and cytokine production, and also elicit Ig production by autologous B cells at levels equivalent to young wild-type mice. These data suggest an IGF-immune axis of healthy longevity. Controlling the availability of IGF in the thymus by targeted manipulation of PAPPA could be a way to maintain immune homeostasis during postnatal development and aging. PMID:19549878

Effects of Aging on Cortical Neural Dynamics and Local Sleep Homeostasis in Mice

PubMed Central

Fisher, Simon P.; Cui, Nanyi; Peirson, Stuart N.; Foster, Russell G.

2018-01-01

Healthy aging is associated with marked effects on sleep, including its daily amount and architecture, as well as the specific EEG oscillations. Neither the neurophysiological underpinnings nor the biological significance of these changes are understood, and crucially the question remains whether aging is associated with reduced sleep need or a diminished capacity to generate sufficient sleep. Here we tested the hypothesis that aging may affect local cortical networks, disrupting the capacity to generate and sustain sleep oscillations, and with it the local homeostatic response to sleep loss. We performed chronic recordings of cortical neural activity and local field potentials from the motor cortex in young and older male C57BL/6J mice, during spontaneous waking and sleep, as well as during sleep after sleep deprivation. In older animals, we observed an increase in the incidence of non-rapid eye movement sleep local field potential slow waves and their associated neuronal silent (OFF) periods, whereas the overall pattern of state-dependent cortical neuronal firing was generally similar between ages. Furthermore, we observed that the response to sleep deprivation at the level of local cortical network activity was not affected by aging. Our data thus suggest that the local cortical neural dynamics and local sleep homeostatic mechanisms, at least in the motor cortex, are not impaired during healthy senescence in mice. This indicates that powerful protective or compensatory mechanisms may exist to maintain neuronal function stable across the life span, counteracting global changes in sleep amount and architecture. SIGNIFICANCE STATEMENT The biological significance of age-dependent changes in sleep is unknown but may reflect either a diminished sleep need or a reduced capacity to generate deep sleep stages. As aging has been linked to profound disruptions in cortical sleep oscillations and because sleep need is reflected in specific patterns of cortical activity, we

Relationship between hyposalivation and oxidative stress in aging mice.

PubMed

Yamauchi, Yoshitaka; Matsuno, Tomonori; Omata, Kazuhiko; Satoh, Tazuko

2017-07-01

The increase in oxidative stress that accompanies aging has been implicated in the abnormal advance of aging and in the onset of various systemic diseases. However, the details of what effects the increase in oxidative stress that accompanies aging has on saliva secretion are not known. In this study, naturally aging mice were used to examine the stimulated whole saliva flow rate, saliva and serum oxidative stress, antioxidant level, submandibular gland H-E staining, and immunofluorescence staining to investigate the effect of aging on the volume of saliva secretion and the relationship with oxidative stress, as well as the effect of aging on the structure of salivary gland tissue. The stimulated whole saliva flow rate decreased significantly with age. Also, oxidative stress increased significantly with age. Antioxidant levels, however, decreased significantly with age. Structural changes of the submandibular gland accompanying aging included atrophy of parenchyma cells and fatty degeneration and fibrosis of stroma, and the submandibular gland weight ratio decreased. These results suggest that oxidative stress increases with age, not just systemically but also locally in the submandibular gland, and that oxidative stress causes changes in the structure of the salivary gland and is involved in hyposalivation.

Learning Impairments, Memory Deficits, and Neuropathology in Aged Tau Transgenic Mice Are Dependent on Leukotrienes Biosynthesis: Role of the cdk5 Kinase Pathway.

PubMed

Giannopoulos, Phillip F; Chiu, Jian; Praticò, Domenico

2018-06-07

Previous studies showed that the leukotrienes pathway is increased in human tauopathy and that its manipulation may modulate the onset and development of the pathological phenotype of tau transgenic mice. However, whether interfering with leukotrienes biosynthesis is beneficial after the behavioral deficits and the neuropathology have fully developed in these mice is not known. To test this hypothesis, aged tau transgenic mice were randomized to receive zileuton, a specific leukotriene biosynthesis inhibitor, or vehicle starting at 12 months of age for 16 weeks and then assessed in their functional and pathological phenotype. Compared with baseline, we observed that untreated tau mice had a worsening of their memory and spatial learning. By contrast, tau mice treated with zileuton had a reversal of these deficits and behaved in an undistinguishable manner from wild-type mice. Leukotriene-inhibited tau mice had an amelioration of synaptic integrity, lower levels of neuroinflammation, and a significant reduction in tau phosphorylation and pathology, which was secondary to an involvement of the cdk5 kinase pathway. Taken together, our findings represent the first demonstration that the leukotriene biosynthesis is functionally involved at the later stages of the tau pathological phenotype and represents an ideal target with viable therapeutic potential for treating human tauopathies.

Age- and region-specific imbalances of basal amino acids and monoamine metabolism in limbic regions of female Fmr1 knock-out mice.

PubMed

Gruss, Michael; Braun, Katharina

2004-07-01

The Fragile X syndrome, a common form of mental retardation in humans, originates from the loss of expression of the Fragile X mental retardation gene leading to the absence of the encoded Fragile X mental retardation protein 1 (FMRP). A broad pattern of morphological and behavioral abnormalities is well described for affected humans as well as Fmr1 knock-out mice, a transgenic animal model for the human Fragile X syndrome. In the present study, we examined neurochemical differences between female Fmr1 knock-out and wildtype mice with particular focus on neurotransmission. Significant age- and region-specific differences of basal tissue neurotransmitter and metabolite levels measured by high performance liquid chromatography were found. Those differences were more numerous in juvenile animals (postnatal day (PND) 28-31) compared to adults (postnatal day 209-221). In juvenile female knock-out mice, especially aspartate and taurine were increased in cortical regions, striatum, cerebellum, and brainstem. Furthermore, compared to the wildtype animals, the juvenile knock-out mice displayed an increased level of neuronal inhibition in the hippocampus and brainstem reflected by decreased ratios of (aspartate + glutamate)/(taurine + GABA), as well as an increased dopamine (DA) turnover in cortical regions, striatum, and hippocampus. These results provide the first evidence that the lack of FMRP expression in female Fmr1 knock-out mice is accompanied by age-dependent, region-specific alterations in brain amino acids, and monoamine turnover, which might be related to the reported synaptical and behavioural alterations in these animals.

Histologic and biochemical alterations predict pulmonary mechanical dysfunction in aging mice with chronic lung inflammation

PubMed Central

Laskin, Debra L.; Gow, Andrew J.

2017-01-01

Both aging and chronic inflammation produce complex structural and biochemical alterations to the lung known to impact work of breathing. Mice deficient in surfactant protein D (Sftpd) develop progressive age-related lung pathology characterized by tissue destruction/remodeling, accumulation of foamy macrophages and alteration in surfactant composition. This study proposes to relate changes in tissue structure seen in normal aging and in chronic inflammation to altered lung mechanics using a computational model. Alterations in lung function in aging and Sftpd -/- mice have been inferred from fitting simple mechanical models to respiratory impedance data (Zrs), however interpretation has been confounded by the simultaneous presence of multiple coexisting pathophysiologic processes. In contrast to the inverse modeling approach, this study uses simulation from experimental measurements to recapitulate how aging and inflammation alter Zrs. Histologic and mechanical measurements were made in C57BL6/J mice and congenic Sftpd-/- mice at 8, 27 and 80 weeks of age (n = 8/group). An anatomic computational model based on published airway morphometry was developed and Zrs was simulated between 0.5 and 20 Hz. End expiratory pressure dependent changes in airway caliber and recruitment were estimated from mechanical measurements. Tissue elements were simulated using the constant phase model of viscoelasticity. Baseline elastance distribution was estimated in 8-week-old wild type mice, and stochastically varied for each condition based on experimentally measured alteration in elastic fiber composition, alveolar geometry and surfactant composition. Weighing reduction in model error against increasing model complexity allowed for identification of essential features underlying mechanical pathology and their contribution to Zrs. Using a maximum likelihood approach, alteration in lung recruitment and diminished elastic fiber density were shown predictive of mechanical alteration at

Histologic and biochemical alterations predict pulmonary mechanical dysfunction in aging mice with chronic lung inflammation.

PubMed

Massa, Christopher B; Groves, Angela M; Jaggernauth, Smita U; Laskin, Debra L; Gow, Andrew J

2017-08-01

Both aging and chronic inflammation produce complex structural and biochemical alterations to the lung known to impact work of breathing. Mice deficient in surfactant protein D (Sftpd) develop progressive age-related lung pathology characterized by tissue destruction/remodeling, accumulation of foamy macrophages and alteration in surfactant composition. This study proposes to relate changes in tissue structure seen in normal aging and in chronic inflammation to altered lung mechanics using a computational model. Alterations in lung function in aging and Sftpd -/- mice have been inferred from fitting simple mechanical models to respiratory impedance data (Zrs), however interpretation has been confounded by the simultaneous presence of multiple coexisting pathophysiologic processes. In contrast to the inverse modeling approach, this study uses simulation from experimental measurements to recapitulate how aging and inflammation alter Zrs. Histologic and mechanical measurements were made in C57BL6/J mice and congenic Sftpd-/- mice at 8, 27 and 80 weeks of age (n = 8/group). An anatomic computational model based on published airway morphometry was developed and Zrs was simulated between 0.5 and 20 Hz. End expiratory pressure dependent changes in airway caliber and recruitment were estimated from mechanical measurements. Tissue elements were simulated using the constant phase model of viscoelasticity. Baseline elastance distribution was estimated in 8-week-old wild type mice, and stochastically varied for each condition based on experimentally measured alteration in elastic fiber composition, alveolar geometry and surfactant composition. Weighing reduction in model error against increasing model complexity allowed for identification of essential features underlying mechanical pathology and their contribution to Zrs. Using a maximum likelihood approach, alteration in lung recruitment and diminished elastic fiber density were shown predictive of mechanical alteration at

Intermittent calorie restriction largely counteracts the adverse health effects of a moderate-fat diet in aging C57BL/6J mice.

PubMed

Rusli, Fenni; Lute, Carolien; Boekschoten, Mark V; van Dijk, Miriam; van Norren, Klaske; Menke, Aswin L; Müller, Michael; Steegenga, Wilma T

2017-05-01

Calorie restriction (CR) has been shown to extend life- and health-span in model species. For most humans, a life-long CR diet is too arduous to adhere to. The aim of this study was to explore whether weekly intermittent CR can (1) provide long-term beneficial effects and (2) counteract diet-induced obesity in male aging mice. In this study, we have exposed C57Bl/6J mice for 24 months to an intermittent (INT) diet, alternating weekly between CR of a control diet and ad libitum moderate-fat (MF) feeding. This weekly intermittent CR significantly counteracted the adverse effects of the MF diet on mortality, body weight, and liver health markers in 24-month-old male mice. Hepatic gene expression profiles of INT-exposed animals appeared much more comparable to CR- than to MF-exposed mice. At 12 months of age, a subgroup of MF-exposed mice was transferred to the INT diet. Gene expression profiles in the liver of the 24-month-old diet switch mice were highly similar to the INT-exposed mice. However, a small subset of genes was consistently changed by the MF diet during the first phase of life. Weekly intermittent CR largely, but not completely, reversed adverse effects caused by a MF diet. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

C-phycocyanin protects against low fertility by inhibiting reactive oxygen species in aging mice

PubMed Central

Li, Yan-Jiao; Han, Zhe; Ge, Lei; Zhou, Cheng-Jie; Zhao, Yue-Fang; Wang, Dong-Hui; Ren, Jing; Niu, Xin-Xin; Liang, Cheng-Guang

2016-01-01

Women over 35 have higher rates of infertility, largely due to deterioration of oocyte quality characterized by fragmentation, abnormal meiotic spindle-chromosome complexes, and oxidative stress. C-phycocyanin (PC) is a biliprotein enriched in Spirulina platensis that is known to possess antioxidant, anti-inflammatory, and radical-scavenging properties. D-galactose-induced aging acceleration in mice has been extensively used to study aging mechanisms and for pharmaceutical screening. In this study, adult female B6D2F/1 mice injected with D-galactose were used as a model to test the age-reversing effects of PC on degenerated reproductive ability. Our results show that PC can prevent oocyte fragmentation and aneuploidy by maintaining cytoskeletal integrity. Moreover, PC can reverse the expression of antioxidant genes, increase superoxide dismutase (SOD) activity and decrease methane dicarboxylic aldehyde (MDA) content, and normalize mitochondria distribution. PC exerts its benefit by inhibiting reactive oxygen species (ROS) production, which decreases apoptosis. Finally, we observe a significant increase in litter size after PC administration to D-galactose-induced aging mice. Our study demonstrates for the first time that D-galactose-induced impaired female reproductive capability can be partially rescued by the antioxidant effects of PC. PMID:27008700

Dietary Tocotrienol/γ-Cyclodextrin Complex Increases Mitochondrial Membrane Potential and ATP Concentrations in the Brains of Aged Mice

PubMed Central

Schloesser, Anke; Esatbeyoglu, Tuba; Piegholdt, Stefanie; Dose, Janina; Ikuta, Naoko; Okamoto, Hinako; Ishida, Yoshiyuki; Terao, Keiji; Matsugo, Seiichi; Rimbach, Gerald

2015-01-01

Brain aging is accompanied by a decrease in mitochondrial function. In vitro studies suggest that tocotrienols, including γ- and δ-tocotrienol (T3), may exhibit neuroprotective properties. However, little is known about the effect of dietary T3 on mitochondrial function in vivo. In this study, we monitored the effect of a dietary T3/γ-cyclodextrin complex (T3CD) on mitochondrial membrane potential and ATP levels in the brain of 21-month-old mice. Mice were fed either a control diet or a diet enriched with T3CD providing 100 mg T3 per kg diet for 6 months. Dietary T3CD significantly increased mitochondrial membrane potential and ATP levels compared to those of controls. The increase in MMP and ATP due to dietary T3CD was accompanied by an increase in the protein levels of the mitochondrial transcription factor A (TFAM). Furthermore, dietary T3CD slightly increased the mRNA levels of superoxide dismutase, γ-glutamyl cysteinyl synthetase, and heme oxygenase 1 in the brain. Overall, the present data suggest that T3CD increases TFAM, mitochondrial membrane potential, and ATP synthesis in the brains of aged mice. PMID:26301044

The effect of regulatory T-cell depletion on the spectrum of organ-specific autoimmune diseases in nonobese diabetic mice at different ages.

PubMed

Nakahara, Mami; Nagayama, Yuji; Ichikawa, Tatsuki; Yu, Liping; Eisenbarth, George S; Abiru, Norio

2011-09-01

The nonobese diabetic (NOD) mouse spontaneously develops several autoimmune diseases, including type 1 diabetes and to a lesser extent thyroiditis and sialitis. Imbalance between effector T cells (Teffs) and regulatory T cells (Tregs) has recently been proposed as a mechanism for the disease pathogenesis in NOD mice, but previous studies have shown the various outcomes by different timing and methods of Treg-depletion. This study was, therefore, designed to compare the consequences of Treg-depletion by the same method (anti-CD25 antibody) on the spectrum of organ-specific autoimmune diseases in NOD mice of different ages. Treg-depletion by anti-CD25 antibody at 10 days of age accelerated development of all three diseases we examined (insulitis/diabetes, thyroiditis, and sialitis); Treg-depletion at 4 weeks of age accelerated only diabetes but not thyroiditis or sialitis; and Treg-depletion at 12 weeks of age hastened only development of thyroiditis and exhibited little influence on diabetes or sialitis. Increased levels of insulin autoantibodies (IAA) were, however, observed in mice depleted of Tregs at 10 days of age, not in those at 4 weeks. Thus, the consequences of Treg-depletion on the spectrum of organ-specific autoimmune diseases depend on the timing of anti-CD25 antibody injection in NOD mice. Aging gradually tips balance between Teffs and Tregs toward Teff-dominance for diabetes, but this balance for thyroiditis and sialitis likely alters more intricately. Our data also suggest that the levels of IAA are not necessarily correlated with diabetes development.

Structural modifications in the arterial wall during physiological aging and as a result of diabetes mellitus in a mouse model: are the changes comparable?

PubMed

Prévost, G; Bulckaen, H; Gaxatte, C; Boulanger, E; Béraud, G; Creusy, C; Puisieux, F; Fontaine, P

2011-04-01

Vascular accelerated aging represents the major cause of morbidity and mortality in subjects with diabetes mellitus. In the present study, our aim was to compare premature functional and morphological changes in the arterial wall resulting from streptozotocin (STZ)-induced diabetes mellitus in mice over a short-term period with those that develop during physiological aging. The effect of aminoguanidine (AG) on the prevention of these alterations in the diabetic group was also analyzed. The vascular relaxation response to acetylcholine (ACh) in the mouse was tested in isolated segments of phenylephrine (Phe)-precontracted aorta at 2, 4 and 8 weeks (wk) of STZ-induced diabetes and compare to 12- and 84-wk-old mice. Aortic structural changes were investigated, and receptor for AGE (RAGE) aortic expression was quantified by western blot. Compared to the 12-wk control group (76 ± 5%), significant endothelium-dependant relaxation (EDR) impairment was found in the group of 12-wk-old mice, which underwent a 4-wk diabetes-inducing STZ treatment (12wk-4WD) (52 ± 4%; P < 0.01) and was yet more apparent in the group of 16-wk-old mice, which underwent an 8-wk diabetes-inducing STZ treatment (16wk-8WD) (34 ± 4%; P < 0.001). The alteration in EDR was relatively comparable between the diabetic 12wk-4WD group and the 84-wk-old group (52.7 ± 4 vs. 48 ± 4%). Intima/media aortic thickening and aortic structural changes were significantly increased in the diabetic 12wk-4WD group and were even more apparent in the 84-wk group compared to the 12-wk controls. AG treatment in the 12wk-4WD+AG diabetic group significantly improved EDR, decreased RAGE expression and showed an aging preventive effect on the structural changes of the arterial wall. Our study compared EDR linked to physiological aging with that observed in the case of STZ-induced diabetes over a short-term period, and demonstrated the beneficial effect of AG. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Age-dependent Impairment of HIF-1α̣Expression in Diabetic Mice: Correction with Electroporation-facilitated Gene Therapy Increases Wound Healing, Angiogenesis, and Circulating Angiogenic Cells

PubMed Central

Liu, Lixin; Marti, Guy P.; Wei, Xiaofei; Zhang, Xianjie; Zhang, Huafeng; Liu, Ye V.; Nastai, Manuel; Semenza, Gregg L.; Harmon, John W.

2009-01-01

Wound healing is impaired in elderly patients with diabetes mellitus. We hypothesized that age-dependent impairment of cutaneous wound healing in db/db diabetic mice: (a) would correlate with reduced expression of the transcription factor hypoxia-inducible factor 1α (HIF-1α) as well as its downstream target genes; and (b) could be overcome by HIF-1α replacement therapy. Wound closure, angiogenesis, and mRNA expression in excisional skin wounds were analyzed and circulating angiogenic cells were quantified in db/db mice that were untreated or received electroporation-facilitated HIF-1α gene therapy. HIF-1α mRNA levels in wound tissue were significantly reduced in older (4–6 months) as compared to younger (1.5–2 months) db/db mice. Expression of mRNAs encoding the angiogenic cytokines vascular endothelial growth factor (VEGF), angiopoietin 1 (ANGPT1), ANGPT2, platelet derived growth factor B (PDGF-B), and placental growth factor (PLGF) was also impaired in wounds of older db/db mice. Intradermal injection of plasmid gWIZ-CA5, which encodes a constitutively active form of HIF-1α, followed by electroporation, induced increased levels of HIF-1α mRNA at the injection site on day 3 and increased levels of VEGF, PLGF, PDGF-B, and ANGPT2 mRNA on day 7. Circulating angiogenic cells in peripheral blood increased 10-fold in mice treated with gWIZ-CA5. Wound closure was significantly accelerated in db/db mice treated with gWIZ-CA5 as compared to mice treated with empty vector. Thus, HIF-1α gene therapy corrects the age-dependent impairment of HIF-1α expression, angiogenic cytokine expression, and circulating angiogenic cells that contribute to the age-dependent impairment of wound healing in db/db mice. PMID:18506785

Role of superoxide–nitric oxide interactions in the accelerated age-related loss of muscle mass in mice lacking Cu,Zn superoxide dismutase

PubMed Central

Sakellariou, Giorgos K; Pye, Deborah; Vasilaki, Aphrodite; Zibrik, Lea; Palomero, Jesus; Kabayo, Tabitha; McArdle, Francis; Van Remmen, Holly; Richardson, Arlan; Tidball, James G; McArdle, Anne; Jackson, Malcolm J

2011-01-01

Summary Mice lacking Cu,Zn superoxide dismutase (SOD1) show accelerated, age-related loss of muscle mass. Lack of SOD1 may lead to increased superoxide, reduced nitric oxide (NO), and increased peroxynitrite, each of which could initiate muscle fiber loss. Single muscle fibers from flexor digitorum brevis of wild-type (WT) and Sod1−/− mice were loaded with NO-sensitive (4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate, DAF-FM) and superoxide-sensitive (dihydroethidium, DHE) probes. Gastrocnemius muscles were analyzed for SOD enzymes, nitric oxide synthases (NOS), and 3-nitrotyrosine (3-NT) content. A lack of SOD1 did not increase superoxide availability at rest because no increase in ethidium or 2-hydroxyethidium (2-HE) formation from DHE was seen in fibers from Sod1−/− mice compared with those from WT mice. Fibers from Sod1−/− mice had decreased NO availability (decreased DAF-FM fluorescence), increased 3-NT in muscle proteins indicating increased peroxynitrite formation and increased content of peroxiredoxin V (a peroxynitrite reductase), compared with WT mice. Muscle fibers from Sod1−/− mice showed substantially reduced generation of superoxide in response to contractions compared with fibers from WT mice. Inhibition of NOS did not affect DHE oxidation in fibers from WT or Sod1−/− mice at rest or during contractions, but transgenic mice overexpressing nNOS showed increased DAF-FM fluorescence and reduced DHE oxidation in resting muscle fibers. It is concluded that formation of peroxynitrite in muscle fibers is a major effect of lack of SOD1 in Sod1−/− mice and may contribute to fiber loss in this model, and that NO regulates superoxide availability and peroxynitrite formation in muscle. PMID:21443684

Sex- and age-dependent effects of Gpr30 genetic deletion on the metabolic and cardiovascular profiles of diet-induced obese mice.

PubMed

Meoli, Luca; Isensee, Jörg; Zazzu, Valeria; Nabzdyk, Christoph S; Soewarto, Dian; Witt, Henning; Foryst-Ludwig, Anna; Kintscher, Ulrich; Noppinger, Patricia Ruiz

2014-05-01

The G protein-coupled receptor 30 (GPR30) has been claimed as an estrogen receptor. However, the literature reports controversial findings and the physiological function of GPR30 is not fully understood yet. Consistent with studies assigning a role of GPR30 in the cardiovascular and metabolic systems, GPR30 expression has been reported in small arterial vessels, pancreas and chief gastric cells of the stomach. Therefore, we hypothesized a role of GPR30 in the onset and progression of cardiovascular and metabolic diseases. In order to test our hypothesis, we investigated the effects of a high-fat diet on the metabolic and cardiovascular profiles of Gpr30-deficient mice (GPR30-lacZ mice). We found that GPR30-lacZ female, rather than male, mice had significant lower levels of HDL along with an increase in fat liver accumulation as compared to control mice. However, two indicators of cardiac performance assessed by echocardiography, ejection fraction and fractional shortening were both decreased in an age-dependent manner only in Gpr30-lacZ male mice. Collectively our results point to a potential role of Gpr30 in preserving lipid metabolism and cardiac function in a sex- and age-dependent fashion. Copyright © 2014 Elsevier B.V. All rights reserved.

Prevention of Neuromusculoskeletal Frailty in Slow-Aging Ames Dwarf Mice: Longitudinal Investigation of Interaction of Longevity Genes and Caloric Restriction

PubMed Central

Arum, Oge; Rasche, Zachary Andrew; Rickman, Dustin John; Bartke, Andrzej

2013-01-01

Ames dwarf (Prop1 df/df) mice are remarkably long-lived and exhibit many characteristics of delayed aging and extended healthspan. Caloric restriction (CR) has similar effects on healthspan and lifespan, and causes an extension of longevity in Ames dwarf mice. Our study objective was to determine whether Ames dwarfism or CR influence neuromusculoskeletal function in middle-aged (82 ± 12 weeks old) or old (128 ± 14 w.o.) mice. At the examined ages, strength was improved by dwarfism, CR, and dwarfism plus CR in male mice; balance/ motor coordination was improved by CR in old animals and in middle-aged females; and agility/ motor coordination was improved by a combination of dwarfism and CR in both genders of middle-aged mice and in old females. Therefore, extension of longevity by congenital hypopituitarism is associated with improved maintenance of the examined measures of strength, agility, and motor coordination, key elements of frailty during human aging, into advanced age. This study serves as a particularly important example of knowledge related to addressing aging-associated diseases and disorders that results from studies in long-lived mammals. PMID:24155868

Prevention of neuromusculoskeletal frailty in slow-aging ames dwarf mice: longitudinal investigation of interaction of longevity genes and caloric restriction.

PubMed

Arum, Oge; Rasche, Zachary Andrew; Rickman, Dustin John; Bartke, Andrzej

2013-01-01

Ames dwarf (Prop1 (df/df) ) mice are remarkably long-lived and exhibit many characteristics of delayed aging and extended healthspan. Caloric restriction (CR) has similar effects on healthspan and lifespan, and causes an extension of longevity in Ames dwarf mice. Our study objective was to determine whether Ames dwarfism or CR influence neuromusculoskeletal function in middle-aged (82 ± 12 weeks old) or old (128 ± 14 w.o.) mice. At the examined ages, strength was improved by dwarfism, CR, and dwarfism plus CR in male mice; balance/ motor coordination was improved by CR in old animals and in middle-aged females; and agility/ motor coordination was improved by a combination of dwarfism and CR in both genders of middle-aged mice and in old females. Therefore, extension of longevity by congenital hypopituitarism is associated with improved maintenance of the examined measures of strength, agility, and motor coordination, key elements of frailty during human aging, into advanced age. This study serves as a particularly important example of knowledge related to addressing aging-associated diseases and disorders that results from studies in long-lived mammals.

Age and isolation influence steroids release and chemical signaling in male mice.

PubMed

Mucignat-Caretta, Carla; Cavaggioni, Andrea; Redaelli, Marco; Da Dalt, Laura; Zagotto, Giuseppe; Gabai, Gianfranco

2014-05-01

Social interactions in mice involve olfactory signals, which convey information about the emitter. In turn, the mouse social and physiological status may modify the release of chemical cues. In this study, the influences of age and social isolation on the endocrine response and the release of chemical signals were investigated in male CD1 mice, allocated into four groups: Young Isolated (from weaning till 60days; N=6), Adult Isolated (till 180days; N=6), Young Grouped (6 mice/cage; till 60days; N=18), Adult Grouped (6 mice/cage; till 180days; N=18). Mice were transferred in a clean cage to observe the micturition pattern and then sacrificed. Body and organs weights, serum testosterone, dehydroepiandrosterone, corticosterone and the ratio Major Urinary Protein/creatinine were measured. Urinary volatile molecules potentially involved in pheromonal communication were identified. Androgen secretion was greater in isolated mice (P<0.05), suggesting a greater reactivity of the Hypothalamic-Pituitary-Gonadal axis. Grouped mice presented a higher degree of adrenal activity, and young mice showed a higher serum corticosterone (P<0.05) suggesting a greater stimulation of the Hypothalamic-Pituitary-Adrenal axis. The micturition pattern typical of dominant male, consisting in voiding numerous droplets, was observed in Young Isolated mice only, which showed a higher protein/creatinine ratio (P<0.05). Urinary 2-s-butyl-thiazoline was higher in both Young and Adult Isolated mice (P<0.005). Young Isolated mice showed the most prominent difference in both micturition pattern and potentially active substance emission, while long term isolation resulted in a less extreme phenotype; therefore social isolation had a higher impact on young mice hormone and pheromone release. Copyright © 2014 Elsevier Inc. All rights reserved.

Testicular glucose and its transporter GLUT 8 as a marker of age-dependent variation and its role in steroidogenesis in mice.

PubMed

Banerjee, Arnab; Anuradha; Mukherjee, Kaustab; Krishna, Amitabh

2014-11-01

The present study evaluates the hypothesis, that glucose is essential for steroidogenesis and inadequate supply of glucose to the testis may be responsible for decline in steroidogenesis in mice during aging. Mice of different age groups (birth, weaning, puberty, reproductively active, and senescence) were utilized for this study. The changes in glucose, glucose transporter (GLUT), and insulin receptor (IR) level in the testis were evaluated and compared with the testicular steroidogenic parameters such as steroidogenic acute regulatory protein (StAR), 3β-hydroxy steroid dehydrogenase (3β-HSD) and circulating testosterone levels. The result showed significant correlation between changes in GLUT 8 and glucose levels with changes in StAR level in the testis and circulating testosterone level in the mice from birth to senescence. Immunohistochemical analysis showed intense immunostaining of GLUT 8 and IR in the interstitial cells, most likely Leydig cells, in testis of pubertal and reproductively active mice suggesting their relevance in steroidogenesis. The in vitro study showed a significant positive correlation between luteinizing hormone (LH)-induced increase in GLUT 8 and StAR (r = 0.82; P < 0.05) proteins level in the testes with increase in testosterone (r = 0.97; P < 0.05) synthesis of reproductively active mice. This study also showed increased release of lactate with increased uptake of glucose by the testis. Further, intra-testicular treatment of 2-deoxy glucose, to reproductively active mice caused a significant decrease in 3β-HSD enzyme activity in the testis. Based on these findings, it may be concluded that the changes in glucose level either directly or indirectly lead to changes in testicular steroidogenesis during aging. © 2014 Wiley Periodicals, Inc.

Ursodeoxycholic acid decreases age-related adiposity and inflammation in mice

PubMed Central

Oh, Ah-Reum; Bae, Jin-Sik; Lee, Junghoon; Shin, Eunji; Oh, Byung-Chul; Park, Sang-Chul; Cha, Ji-Young

2016-01-01

Ursodeoxycholic acid (UDCA), a natural, hydrophilic nontoxic bile acid, is clinically effective for treating cholestatic and chronic liver diseases. We investigated the chronic effects of UDCA on age-related lipid homeostasis and underlying molecular mechanisms. Twenty-week-old C57BL/6 male and female mice were fed a diet with or without 0.3% UDCA supplementation for 25 weeks. UDCA significantly reduced weight gain, adiposity, hepatic triglyceride, and hepatic cholesterol without incidental hepatic injury. UDCA-mediated hepatic triglyceride reduction was associated with downregulated hepatic expression of peroxisome proliferator-activated receptor-γ, and of other genes involved in lipogenesis (Chrebp, Acaca, Fasn, Scd1, and Me1) and fatty acid uptake (Ldlr, Cd36). The inflammatory cytokines Tnfa, Ccl2, and Il6 were significantly decreased in liver and/or white adipose tissues of UDCA-fed mice. These data suggest that UDCA exerts beneficial effects on age-related metabolic disorders by lowering the hepatic lipid accumulation, while concurrently reducing hepatocyte and adipocyte susceptibility to inflammatory stimuli. [BMB Reports 2016; 49(2): 105-110] PMID:26350747

Impact of N-acetylcysteine and sesame oil on lipid metabolism and hypothalamic-pituitary-adrenal axis homeostasis in middle-aged hypercholesterolemic mice

PubMed Central

Korou, Laskarina-Maria; Agrogiannis, George; Koros, Christos; Kitraki, Efthimia; Vlachos, Ioannis S.; Tzanetakou, Irene; Karatzas, Theodore; Pergialiotis, Vasilios; Dimitroulis, Dimitrios; Perrea, Despina N.

2014-01-01

Hyperlipidemia and stress are important factors affecting cardiovascular health in middle-aged individuals. We investigated the effects of N-acetylcysteine (NAC) and sesame oil on the lipidemic status, liver architecture and the hypothalamic-pituitary-adrenal (HPA) axis of middle-aged mice fed a cholesterol-enriched diet. We randomized 36 middle-aged C57bl/6 mice into 6 groups: a control group, a cholesterol/cholic acid diet group, a cholesterol/cholic acid diet group with NAC supplementation, a cholesterol/cholic acid diet enriched with 10% sesame oil and two groups receiving a control diet enriched with NAC or sesame oil. NAC administration prevented the onset of the disturbed lipid profile, exhibiting decreased lipid peroxidation and alkaline phosphatase (ALP) levels, restored nitric oxide bioavailability and reduced hepatic damage, compared to non-supplemented groups. High-cholesterol feeding resulted in increased hypothalamic glucocorticoid receptors (GR) levels, while NAC supplementation prevented this effect. NAC supplementation presented significant antioxidant capacity by means of preventing serum lipid status alterations, hepatic damage, and HPA axis disturbance due to high-cholesterol feeding in middle-aged mice. These findings suggest a beneficial preventive action of plant-derived antioxidants, such as NAC, on lipid metabolism and on the HPA axis. PMID:25348324

Cyclophilin D Promotes Brain Mitochondrial F1FO ATP Synthase Dysfunction in Aging Mice

PubMed Central

Gauba, Esha; Guo, Lan; Du, Heng

2017-01-01

Brain aging is the known strongest risk factor for Alzheimer’s disease (AD). In recent years, mitochondrial deficits have been proposed to be a common mechanism linking brain aging to AD. Therefore, to elucidate the causative mechanisms of mitochondrial dysfunction in aging brains is of paramount importance for our understanding of the pathogenesis of AD, in particular its sporadic form. Cyclophilin D (CypD) is a specific mitochondrial protein. Recent studies have shown that F1FO ATP synthase oligomycin sensitivity conferring protein (OSCP) is a binding partner of CypD. The interaction of CypD with OSCP modulates F1FO ATP synthase function and mediates mitochondrial permeability transition pore (mPTP) opening. Here, we have found that increased CypD expression, enhanced CypD/OSCP interaction, and selective loss of OSCP are prominent brain mitochondrial changes in aging mice. Along with these changes, brain mitochondria from the aging mice demonstrated decreased F1FO ATP synthase activity and defective F1FO complex coupling. In contrast, CypD deficient mice exhibited substantially mitigated brain mitochondrial F1FO ATP synthase dysfunction with relatively preserved mitochondrial function during aging. Interestingly, the aging-related OSCP loss was also dramatically attenuated by CypD depletion. Therefore, the simplest interpretation of this study is that CypD promotes F1FO ATP synthase dysfunction and the resultant mitochondrial deficits in aging brains. In addition, in view of CypD and F1FO ATP synthase alterations seen in AD brains, the results further suggest that CypD-mediated F1FO ATP synthase deregulation is a shared mechanism linking mitochondrial deficits in brain aging and AD. PMID:27834780

Cyclophilin D Promotes Brain Mitochondrial F1FO ATP Synthase Dysfunction in Aging Mice.

PubMed

Gauba, Esha; Guo, Lan; Du, Heng

2017-01-01

Brain aging is the known strongest risk factor for Alzheimer's disease (AD). In recent years, mitochondrial deficits have been proposed to be a common mechanism linking brain aging to AD. Therefore, to elucidate the causative mechanisms of mitochondrial dysfunction in aging brains is of paramount importance for our understanding of the pathogenesis of AD, in particular its sporadic form. Cyclophilin D (CypD) is a specific mitochondrial protein. Recent studies have shown that F1FO ATP synthase oligomycin sensitivity conferring protein (OSCP) is a binding partner of CypD. The interaction of CypD with OSCP modulates F1FO ATP synthase function and mediates mitochondrial permeability transition pore (mPTP) opening. Here, we have found that increased CypD expression, enhanced CypD/OSCP interaction, and selective loss of OSCP are prominent brain mitochondrial changes in aging mice. Along with these changes, brain mitochondria from the aging mice demonstrated decreased F1FO ATP synthase activity and defective F1FO complex coupling. In contrast, CypD deficient mice exhibited substantially mitigated brain mitochondrial F1FO ATP synthase dysfunction with relatively preserved mitochondrial function during aging. Interestingly, the aging-related OSCP loss was also dramatically attenuated by CypD depletion. Therefore, the simplest interpretation of this study is that CypD promotes F1FO ATP synthase dysfunction and the resultant mitochondrial deficits in aging brains. In addition, in view of CypD and F1FO ATP synthase alterations seen in AD brains, the results further suggest that CypD-mediated F1FO ATP synthase deregulation is a shared mechanism linking mitochondrial deficits in brain aging and AD.

Iron dysregulation combined with aging prevents sepsis-induced apoptosis.