The specific activity of aldolase in the livers of old and young rats

1976 ◽  
Vol 54 (2) ◽  
pp. 194-196 ◽  
Author(s):  
Peter J. Anderson
Keyword(s):  
Catalytic Activity ◽  
Specific Activity ◽  
Young Rats ◽  
Old Rats ◽  
Enzyme Molecules ◽  
Altered Proteins ◽  
Fructose Biphosphate

The catalytic activity of liver fructose-biphosphate aldolase (EC 4.1.2.13) of young and old rats in units per manomole sequence has been calculated. No evidence of the accumulation with age of altered enzyme molecules of low catalytic activity was obtained. This is contrary to results obtained using mice and rabbits and indicates that the accumulation of altered enzymes may not always be associated with aging. The possibility that altered proteins are formed, but do not accumulate, cannot be ruled out.

scholarly journals Aging and acute exercise enhance free radical generation in rat skeletal muscle

1999 ◽  
Vol 87 (1) ◽  
pp. 465-470 ◽  
Author(s):  
J. Bejma ◽  
L. L. Ji
Keyword(s):  
Skeletal Muscle ◽  
Lipid Peroxidation ◽  
Acute Exercise ◽  
Muscle Protein ◽  
Vastus Lateralis ◽  
Age Groups ◽  
Protein Carbonyl ◽  
Biological Aging ◽  
Young Rats ◽  
Old Rats

Reactive oxygen species (ROS) are implicated in the mechanism of biological aging and exercise-induced oxidative damage. The present study examined the effect of an acute bout of exercise on intracellular ROS production, lipid and protein peroxidation, and GSH status in the skeletal muscle of young adult (8 mo, n = 24) and old (24 mo, n = 24) female Fischer 344 rats. Young rats ran on a treadmill at 25 m/min and 5% grade until exhaustion (55.4 ± 2.7 min), whereas old rats ran at 15 m/min and 5% grade until exhaustion (58.0 ± 2.7 min). Rate of dichlorofluorescin (DCFH) oxidation, an indication of ROS and other intracellular oxidants production in the homogenate of deep vastus lateralis, was 77% ( P < 0.01) higher in rested old vs. young rats. Exercise increased DCFH oxidation by 38% ( P < 0.09) and 50% ( P < 0.01) in the young and old rats, respectively. DCFH oxidation in isolated deep vastus lateralis mitochondria with site 1 substrates was elevated by 57% ( P < 0.01) in old vs. young rats but was unaltered with exercise. Significantly higher DCFH oxidation rate was also found in aged-muscle mitochondria ( P < 0.01), but not in homogenates, when ADP, NADPH, and Fe3+ were included in the assay medium without substrates. Lipid peroxidation in muscle measured by malondialdehyde content showed no age effect, but was increased by 20% ( P < 0.05) with exercise in both young and old rats. Muscle protein carbonyl formation was unaffected by either age or exercise. Mitochondrial GSH/ GSSG ratio was significantly higher in aged vs. young rats ( P < 0.05), whereas exercise increased GSSG content and decreased GSH/GSSG in both age groups ( P < 0.05). These data provided direct evidence that oxidant production in skeletal muscle is increased in old age and during prolonged exercise, with both mitochondrial respiratory chain and NADPH oxidase as potential sources. The alterations of muscle lipid peroxidation and mitochondrial GSH status were consistent with these conclusions.

Renal expression of osteopontin and alkaline phosphatase correlates with BUN levels in aged rats

1995 ◽  
Vol 269 (3) ◽  
pp. F398-F404
Author(s):  
C. T. Liang ◽  
J. Barnes
Keyword(s):  
Alkaline Phosphatase ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Blot Hybridization ◽  
Northern Blot Hybridization ◽  
Tgf Beta ◽  
Young Rats ◽  
Beta Actin ◽  
Old Rats ◽  
Renal Expression

Renal expression of alkaline phosphatase (AP) and osteopontin (OP) in rats of different age was examined. Northern blot hybridization showed that AP mRNA was reduced moderately, whereas OP mRNA was stimulated drastically in old rats. Dot-blot quantitation analysis showed that AP mRNA decreased 30% in 24-compared with 6-mo-old rats. In contrast, OP mRNA increased 3.1- and 9.1-fold, respectively, in 12- and 24-mo-old rats. beta-Actin mRNA did not change with age. Blood urea nitrogen (BUN) increased 47 and 187% in 12- and 24-mo-old rats, respectively. Correlation analysis showed that BUN correlated negatively with AP mRNA and positively with OP mRNA. No correlation was observed with beta-actin. The expression of these markers was also examined in femurs. AP and OP mRNAs were marginally reduced in old bones. To test whether the correlation also exists in other types of renal insufficiency, we examined these parameters in young rats infused with parathyroid hormone (PTH). BUN was elevated 3.5-fold, whereas AP mRNA decreased 48%, and OP mRNA increased 15.3-fold in kidneys of PTH-treated rats. To elucidate the possible mechanisms that lead to the overexpression of OP in kidney, we examined the expression of transforming growth factor-beta 1 (TGF-beta 1) mRNA. No significant differences in TGF-beta 1 expression were observed between young and old rats and control and PTH-treated young rats. Changes in the expression of OP were also visualized by immunostaining of renal sections. Alterations in the levels of OP and AP were validated by Western blot analysis and enzyme assay of homogenate, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Phosphodiesterase Activities in the Eye of Old and Young Rats in Normoxic, Hypoxic and Hyperoxic Atmospheres

2003 ◽  
Vol 1 (1) ◽  
pp. 25-32 ◽  
Author(s):  
G. Spoto ◽  
A. Contento ◽  
M. Di Nicola ◽  
G. Bianchi ◽  
C. Di Giulio ◽  
...  
Keyword(s):  
Cyclic Nucleotides ◽  
Biological Effects ◽  
Atmospheric Oxygen ◽  
Second Messengers ◽  
Camp Phosphodiesterase ◽  
Young Rats ◽  
Physiological Processes ◽  
Adaptive Processes ◽  
Old Rats

Phosphodiesterase activity was tested on homogenized eyes of young and old rats kept in hypoxic and hyperoxic conditions, with the aim of correlating any difference in PDE activity with aging and variations in atmospheric oxygen contents. The activities of the two enzymes, cAMP phosphodiesterase (cAMP-PDE) and cGMP phosphodiesterase (cGMP-PDE), were tested. Phosphodiesterases seem to be particularly susceptible to variations in oxygen tension, suggesting an important role of cyclic nucleotides in cellular adaptive processes. Particularly, cAMP-PDE activity increases lightly both in hypoxic and hyperoxic conditions in young and old rats. For cGMP-PDE activity of young rats, a similar behaviour to cAMP-PDE activity is observed with a similar increase in hypoxic and hyperoxic conditions respect to the control rats. Instead old rats seem to be quite insensible to hypoxia, while they show a fair increase in cGMP-PDE activity in the case of hyperoxia. The second messengers cAMP and cGMP play important roles in mediating the biological effects of a wide variety of first messengers. The intracellular levels of cyclic nucleotides depend upon rates of synthesis and degradation, actuated, respectively, by cyclases and phosphodiesterases (PDEs). Therefore, PDEs seem to play an important role in a wide variety of physiological processes.

Plasma from young rats injected into old rats induce anti-aging effects

2020 ◽  
Author(s):  
Shambhoo Sharan Tripathi ◽  
Raushan Kumar ◽  
Jitendra Arya ◽  
Syed Ibrahim Rizvi
Keyword(s):  
Aging Effects ◽  
Young Rats ◽  
Old Rats

scholarly journals Effect of aging on UVC-induced apoptosis of rat splenocytes.

2000 ◽  
Vol 47 (2) ◽  
pp. 339-347 ◽  
Author(s):  
E Radziszewska ◽  
K Piwocka ◽  
A Bielak-Zmijewska ◽  
J Skierski ◽  
E Sikora
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Morphological Changes ◽  
Transcription Factor Activity ◽  
Factor Activity ◽  
Dna Ladder ◽  
Young Rats ◽  
Bax Protein ◽  
Old Rats ◽  
Induced Apoptosis

UVC-induced apoptotic symptoms such as morphological changes, DNA fragmentation, Bcl-2 and Bax protein expression were examined in primary splenocyte cultures from young (3 months) and old (24 months) rats. The activities of AP-1 and CRE transcription factors in UVC-irradiated splenocytes were also assessed. At 24 h after UVC irradiation 40% of cells derived from young rats were found to be apoptotic, which was twice as much as in splenocytes from old rats. Apoptosis in cells from old rats did not give typical symptoms like a "DNA ladder" and Bcl-2 protein downregulation, in contrast to splenocytes from young rats. No AP-1 transcription factor activity was found in UVC-irradiated splenocytes from old animals and only a trace activity in splenocytes from young animals. This indicates that, UVC-induced apoptosis in rat splenocytes is practically AP-1 independent and that cells from old rats are less sensitive to UVC irradiation than splenocytes from young rats.

scholarly journals Potential urinary aging markers of 20-month-old rats

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2058 ◽  
Author(s):  
Xundou Li ◽  
Youhe Gao
Keyword(s):  
Biomarker Discovery ◽  
The Body ◽  
Disease Biomarkers ◽  
Urinary Proteome ◽  
Human Orthologs ◽  
Human Protein Atlas ◽  
Aging Conditions ◽  
Old Rats ◽  
Spectral Counts ◽  
Altered Proteins

Urine is a very good source for biomarker discovery because it accumulates changes in the body. However, a major challenge in urinary biomarker discovery is the fact that the urinary proteome is influenced by various elements. To circumvent these problems, simpler systems, such as animal models, can be used to establish associations between physiological or pathological conditions and alterations in the urinary proteome. In this study, the urinary proteomes of young (two months old) and old rats (20 months old; nine in each group) were analyzed using LC-MS/MS and quantified using the Progenesis LC-MS software. A total of 371 proteins were identified, 194 of which were shared between the young and old rats. Based on criteria of a fold change ≥2,P< 0.05 and identification in each rat of the high-abundance group, 33 proteins were found to be changed (15 increased and 18 decreased in old rats). By adding a more stringent standard (protein spectral counts from every rat in the higher group greater than those in the lower group), eight proteins showed consistent changes in all rats of the groups; two of these proteins are also altered in the urinary proteome of aging humans. However, no shared proteins between our results and the previous aging plasma proteome were identified. Twenty of the 33 (60%) altered proteins have been reported to be disease biomarkers, suggesting that aging may share similar urinary changes with some diseases. The 33 proteins corresponded to 28 human orthologs which, according to the Human Protein Atlas, are strongly expressed in the kidney, intestine, cerebellum and lung. Therefore, the urinary proteome may reflect aging conditions in these organs.

scholarly journals Gut Microbiota Is Involved in Alcohol-Induced Osteoporosis in Young and Old Rats Through Immune Regulation

2021 ◽  
Vol 11 ◽  
Author(s):  
Ming Cheng ◽  
Bo Tan ◽  
Xiaojing Wu ◽  
Feng Liao ◽  
Fei Wang ◽  
...  
Keyword(s):  
Alcohol Consumption ◽  
Gut Microbiota ◽  
Bone Metabolism ◽  
Alcohol Metabolism ◽  
Excessive Alcohol Consumption ◽  
Young Rats ◽  
Age Related ◽  
Different Ages ◽  
Old Rats

Long-term and excessive alcohol consumption are risk factors for osteoporosis. Excessive drinking can reduce bone density and also cause imbalance of gut microbiota. And gut microbiota can affect bone metabolism through various mechanisms, and the regulation of gut microbiota is closely related to age. However, the effects of gut microbiota on alcohol-induced osteoporosis at different ages are unclear. In this study, young and old rats were used to induce osteoporosis by long-term alcohol consumption, and alcohol metabolism, bone morphology, bone absorption and immune activity of rats were analyzed to determine the effects of alcohol on rats of different ages. In addition, changes of gut microbiota in rats were analyzed to explore the role of gut microbiota in alcohol-induced osteoporosis in rats of different ages. The results showed the ability of alcohol metabolism was only associated with age, but not with alcohol consumption. Long-term alcohol consumption resulted in the changes of bone metabolism regulating hormones, bone loss, activation of receptor activator of NF-κB ligand (RANKL) signaling and inflammatory response. And osteoporosis was more severe in old rats than young rats, suggesting that alcohol-induced osteoporosis is age-related. In addition, long-term drinking also affected the composition of gut microbiota in rats, with a significant increase in the proportion of pro-inflammatory microorganisms. Overall, this study found that long-term alcohol consumption induced osteoporosis and affected the composition of gut microbiota. And alcohol can activate T lymphocytes directly or indirectly by regulating the changes of gut microbiota to produce cytokines, and further activate osteoclasts. In addition, the osteoporosis was more severe in the old rats than young rats, which may be due to the higher diversity and stronger regulation ability of gut microbiota in young rats compared with old rats.

scholarly journals Arginase inhibition restores NOS coupling and reverses endothelial dysfunction and vascular stiffness in old rats

2009 ◽  
Vol 107 (4) ◽  
pp. 1249-1257 ◽  
Author(s):  
Jae Hyung Kim ◽  
Lukasz J. Bugaj ◽  
Young Jun Oh ◽  
Trinity J. Bivalacqua ◽  
Sungwoo Ryoo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Vascular Stiffness ◽  
Arginase Activity ◽  
Young Rats ◽  
Arginase 1 ◽  
Enos Uncoupling ◽  
Old Rats

There is increasing evidence that upregulation of arginase contributes to impaired endothelial function in aging. In this study, we demonstrate that arginase upregulation leads to endothelial nitric oxide synthase (eNOS) uncoupling and that in vivo chronic inhibition of arginase restores nitroso-redox balance, improves endothelial function, and increases vascular compliance in old rats. Arginase activity in old rats was significantly increased compared with that shown in young rats. Old rats had significantly lower nitric oxide (NO) and higher superoxide (O2−) production than young. Acute inhibition of both NOS, with NG-nitro-l-arginine methyl ester, and arginase, with 2( S)-amino- 6-boronohexanoic acid (ABH), significantly reduced O2− production in old rats but not in young. In addition, the ratio of eNOS dimer to monomer in old rats was significantly decreased compared with that shown in young rats. These results suggest that eNOS was uncoupled in old rats. Although the expression of arginase 1 and eNOS was similar in young and old rats, inducible NOS (iNOS) was significantly upregulated. Furthermore, S-nitrosylation of arginase 1 was significantly elevated in old rats. These findings support our previously published finding that iNOS nitrosylates and activates arginase 1 (Santhanam et al., Circ Res 101: 692–702, 2007). Chronic arginase inhibition in old rats preserved eNOS dimer-to-monomer ratio and significantly reduced O2− production and enhanced endothelial-dependent vasorelaxation to ACh. In addition, ABH significantly reduced vascular stiffness in old rats. These data indicate that iNOS-dependent S-nitrosylation of arginase 1 and the increase in arginase activity lead to eNOS uncoupling, contributing to the nitroso-redox imbalance, endothelial dysfunction, and vascular stiffness observed in vascular aging. We suggest that arginase is a viable target for therapy in age-dependent vascular stiffness.

Moving into Nanotechnology Roles to Mimic and Boost Enzyme Activity

2018 ◽  
pp. 421-440
Author(s):  
Maria Laura Soriano
Keyword(s):  
Enzyme Activity ◽  
Catalytic Activity ◽  
Enzyme Immobilization ◽  
Mesoporous Materials ◽  
Specific Activity ◽  
Artificial Enzymes ◽  
Catalytic Nanoparticles ◽  
Solid Liquid ◽  
By Products ◽  
Insight Into

A new tendency toward the design of artificial enzymes based on nanostructures (nanodots, nanofibers, mesoporous materials) has emerged. On one hand, nanotechnology bestows self-catalytic nanoparticles with a specific activity to achieve efficient reactions with low number of by-products. On other hand, the nanoparticles may behave as nanometric scaffolds for hosting enzymes, promoting their catalytic activity and stability. In this case, enzyme immobilization requires the preservation of the catalytic activity by preventing enzyme unfolding and avoiding its aggregation. These approaches render many other advantages like hosting/storing enzymes in nanotechnological solid, liquid, and gel-like media. This chapter focuses on the most up-to-date approaches to manipulate or mimic enzyme activity based on nanotechnology, and offers examples of their applications in the most promising fields. It also gives new insight into the creation of reusable nanotechnological tools for enzyme storage.

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