Age-Related Changes in Antioxidative Enzyme Capacity in Tongue of Fischer 344 Rats

Abstract

ObjectivesAntioxidative enzyme efficiency changes in some organs with age. However, no study has been conducted on age-related antioxidant enzyme changes in tongue. In the present study, the authors investigated the activities of four antioxidative enzymes and their protein expressions in the tongues of young and old Fischer 344 rats.MethodsAge-dependent changes in the enzyme activities of total superoxide dismutase (SOD), Mn-SOD, Cu/Zn-SOD, catalase (CAT), and glutathione peroxidase (GPx) were determined using chemical kits, and the protein expressions levels of these enzymes by Western blotting. The study was conducted using rats aged 7 months (the young group, n=8) and 22 months (the old group, n=8).ResultsTotal SOD, Cu/Zn-SOD, and GPx activities in the tongues of old rats were lower than in young rats, and similarly, corresponding protein expressions were downregulated in old rats. On the other hand, although the protein expressions of Mn-SOD and CAT were lower in old rats, their enzyme activities were not.ConclusionThe results of this study provide a possible mechanism for the tongue aging process, as in old Fischer 344 rats the antioxidant defense system was diminished with respect to enzyme activity levels and protein abundances.

Age-Related Changes in Nuclear Factor Erythroid 2-Related Factor 2 and Reactive Oxygen Species and Mitochondrial Structure in the Tongues of Fischer 344 Rats

“…In the present study, Western blotting showed that Nrf2 expression was suppressed in the tongue tissues of aged rats, which is in-line with our previous observation that antioxidant enzyme levels were diminished in aged rat tongues [ 5 ]. Smith et al [ 14 ] focused on miRNA-146a, the expression of which leads to age-associated reductions in Nrf2 expression.…”

“…Further studies are needed to assess whether aged tongue tissues are prone to certain mitochondrial DNA mutations and to identify the factors that contribute to such mutations. In the present study, ROS were found to be up-regulated in an aged rat tongues, and based on our previous finding that antioxidant enzyme levels were reduced in aged rat tongues [ 5 ], we suggest the up-regulation of ROS was possibly caused by diminished antioxidant enzyme levels.…”

“…In a previous study, we showed the activities of total SOD, GPx, and Cu/Zn-SOD were lower in the tongues of aged rats than in those of young rats, and that their protein expressions were down-regulated in old rats [ 5 ]. On the other hand, although the protein expressions of Mn-SOD and CAT were lower in old rats, their enzyme activities were not [ 5 ]. Aging-associated impaired mitochondrial biogenesis has been associated with reduced levels and activities of nuclear factor erythroid 2-related factor 2 (Nrf2) [ 6 ].…”

Leptin concentration and oxidative stress in diabetic ketoacidosis

“…8 In addition, persistent oxidative stress plays a key role in the pathogenesis and complications of diabetes. 11 Leptin is a hormone that is encoded by the leptin gene and secreted by adipocytes to regulate energy metabolism homoeostasis. For example, a previous study demonstrated that the activities of total superoxide dismutase (SOD), glutathione peroxidase (GPx) and copper/zinc (Cu/Zn) SOD are significantly lower on the tongues of aged rats compared with young rats, and the antioxidant defence system of aged rats is significantly declined.…”

“…For example, a previous study demonstrated that the activities of total superoxide dismutase (SOD), glutathione peroxidase (GPx) and copper/zinc (Cu/Zn) SOD are significantly lower on the tongues of aged rats compared with young rats, and the antioxidant defence system of aged rats is significantly declined. 11 Leptin is a hormone that is encoded by the leptin gene and secreted by adipocytes to regulate energy metabolism homoeostasis. Once secreted into the circulation, it binds to the leptin receptor in the hypothalamus to function as an anorexigenic agent and promote energy consumption.…”