共查询到20条相似文献,搜索用时 31 毫秒
1.
Yi SS Hwang IK Yoo KY Park OK Yu J Yan B Kim IY Kim YN Pai T Song W Lee IS Won MH Seong JK Yoon YS 《Neurochemical research》2009,34(6):1039-1046
In the present study, we investigated the effects of a treadmill exercise on serum glucose levels and Ki67 and doublecortin
(DCX) immunoreactivity, which is a marker of cell proliferation expressed during cell cycles except G0 and early G1 and a
marker of progenitors differentiating into neurons, respectively, in the subgranular zone of the dentate gyrus (SZDG) using
a type II diabetic model. At 6 weeks of age, Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats were put on a
treadmill with or without running for 1 h/day/5 consecutive days at 22 m/min for 5 weeks. Body weight was significantly increased
in the control (without running)-ZDF rats compared to that in the other groups. In the control groups blood glucose levels
were increased by 392.7 mg/dl in the control-ZDF rats and by 143.3 mg/dl in the control-ZLC rats. However, in the exercise
groups, blood glucose levels were similar between the exercise-ZLC and ZDF rats: The blood glucose levels were 110.0 and 118.2 mg/dl,
respectively. Ki67 positive nuclei were detected in the SZDG in control and exercise groups. The number of Ki67 positive nuclei
was significantly high in exercise groups compared to that in the control groups. In addition, Ki67 positive cells were abundant
in ZLC groups compared to those in ZDF groups. DCX-immunoreactive structures in the control-ZDF rats were lower than that
in the control-ZLC rats. In the exercise groups, DCX-immunoreactive structures (somata and processes with tertiary dendrites)
and DCX protein levels were markedly increased in both the exercise-ZLC and ZDF rats compared to that in the control groups.
These results suggest that a treadmill exercise reduces blood glucose levels in ZDF rats and increases cell proliferation
and differentiation in the SZDG in ZLC and ZDF rats compared to those in control groups. 相似文献
2.
In Koo Hwang Il Yong Kim Eun Jung Joo Jae Hoon Shin Ji Won Choi Moo-Ho Won Yeo Sung Yoon Je Kyung Seong 《Neurochemical research》2010,35(4):645-650
In this study, we observed the effects of metformin, one of the most widely prescribed drugs for the treatment of type 2 diabetes,
on cell proliferation and neuroblast differentiation in the subgranular zone of the hippocampal dentate gyrus (SZDG) in Zucker
diabetic fatty (ZDF) rats, which are a model for type 2 diabetes. For this, metformin was administered orally once a day to
14-week-old ZDF rats for 2 weeks and the animals were sacrificed at 16 weeks of age. During this period, blood glucose levels
were higher in the vehicle-treated ZDF rats than in the Zucker lean control (ZLC) rats. Metformin treatment significantly
decreased the blood glucose levels from 15.5 weeks of age. In the SZDG, Ki67 (a marker for cell proliferation)- and doublecortin
(DCX, a marker for differentiated neuroblasts)-immunoreactive cells were much lower in the vehicle-treated ZDF rats than in
the ZLC rats. In the metformin-treated ZDF group, Ki67- and DCX-immunoreactive cells were significantly increased in the SZDG
compared to those in the vehicle-treated ZDF group. These results suggest that diabetes significantly reduces cell proliferation
and neuroblast differentiation in the SZDG and that metformin treatment normalizes the reduction of cell proliferation and
neuroblast differentiation in the SZDG in diabetic rats. 相似文献
3.
Hwang IK Yi SS Yoo KY Park OK Yan B Song W Won MH Yoon YS Seong JK 《Neurochemical research》2011,36(2):281-287
Abnormal excess of glucocorticoid is one of feature characteristics in type 2 diabetes. In the present study, we investigated
the effect of treadmill exercise at chronic diabetic stages on glucocorticoid receptor (GR) immunoreactivity in the hippocampal
CA1 region and dentate gyrus, which are very vulnerable to diabetes. For this study, we used Zucker diabetic fatty (ZDF) rats
and Zucker lean control (ZLC) rats. Twenty-three-week-old ZLC and ZDF rats were put on the treadmill with or without running
for 7 weeks and sacrificed at 30 weeks of age. Treadmill exercise significantly decreased diabetes-induced blood glucose and
serum corticosteroid levels although they did not drop to control levels. In sedentary ZLC rats, GR immunoreactivity was detected
in pyramidal cells of the CA1 region as well as in granule cells of the dentate gyrus. In the sedentary ZDF rats, GR immunoreactivity
was significantly increased in these regions. However, treadmill exercise significantly decreased GR immunoreactivity in these
regions. These results indicate that treadmill exercise in chronic diabetic rats significantly decreased GR immunoreactivity
in the hippocampal CA1 region and dentate gyrus, although blood glucose and serum corticosteroid levels did not fully recover
to normal state. 相似文献
4.
Hwang IK Yi SS Yoo KY Park OK Yan B Song W Won MH Yoon YS Seong JK 《Neurochemical research》2011,36(8):1526-1532
In the present study, we investigated the effects of treadmill exercise in early and chronic diabetic stages on parvalbumin
(PV) immunoreactivity in the subgranular zone of the dentate gyrus of Zucker diabetic fatty (ZDF) and its lean control rats
(ZLC). To investigate the effects, ZLC and ZDF rats at 6 or 23 weeks of age were put on a treadmill with or without running
for 1 h/day/5 consecutive days at 16–22 m/min for 5 weeks or 12–16 m/min for 7 weeks, respectively. Physical exercise in pre-diabetic
rats prevented onset of diabetes, while exercise in rats at chronic diabetic stage significantly reduced blood glucose levels.
In addition, physical exercise in the pre-diabetic rats significantly increased PV immunoreactive fibers in the strata oriens
and radiatum of the CA1-3 region and in the polymorphic and molecular layers of the dentate gyrus compared to that in sedentary
controls. However, in rats at chronic stages, PV immunoreactivity was slightly increased in the CA1-3 region as well as in
the dentate gyrus compared to that in the sedentary controls. These results suggest that physical exercise has differential
effects on blood glucose levels and PV immunoreactivity according to diabetic stages. Early exercise improves diabetic phenotype
and PV immunoreactive fibers in the rat hippocampus. 相似文献
5.
Nam SM Kim YN Yoo DY Yi SS Kim W Hwang IK Seong JK Yoon YS 《Neurochemical research》2012,37(2):253-260
In this study, we investigated the differences in calbindin D-28k (CB), calretinin, (CR) and parvalbumin (PV) immunoreactivity
in the hippocampus of Zucker diabetic fatty (ZDF) rats and Zucker lean control (ZLC) rats. In addition, we observed the effects
of hypothyroidism on the levels of immunoreactivity of these proteins in ZDF rats. For this study, 7-week-old ZDF rats were
used, and methimazole treatment was continued for 5 weeks to induce hypothyroidism. The animals were sacrificed at 12 weeks
of age. ZDF rats showed increased blood glucose levels compared to those in ZLC rats. Methimazole intervention significantly
reduced total and free T3 levels, and it ameliorated the increase of blood glucose levels in ZDF rats. In ZLC rats, CB, CR,
and PV immunoreactivity was detected in regions of the hippocampus proper. In vehicle-treated ZDF rats, CB, CR, and PV immunoreactivity
was significantly decreased in the hippocampus. However, in the methimazole-treated rats, CB, CR, and PV immunoreactivity
was significantly increased compared to that in the vehicle-treated rats. These results suggest that hypothyroidism ameliorated
the diabetes-induced reduction of CB, CR, and PV immunoreactivity in the hippocampus. 相似文献
6.
Yi SS Hwang IK Chun MS Kim YN Kim IY Lee IS Seong JK Yoon YS 《Neurochemical research》2009,34(5):851-858
Diabetes is a metabolic disorder that is associated with the dysregulation of a number of systems within the body. In the
present study, we investigated glucocorticoid receptor (GR) immunoreactivity and its protein levels in the paraventricular
nuclei of 4-, 12-, 20- and 30-week-old Zucker diabetic fatty (fa/fa, ZDF) and in Zucker lean control (fa/+ or +/+, ZLC) rats, because the progressive induction of diabetes is detectable in this model after 7 weeks of age and chronic diabetic
conditions are maintained after 12 weeks of age. GR immunoreactivity was detected in parvocellular paraventricular nuclei
and this and GR protein levels were exponentially increased according to the ages. In particular, GR immunoreactivities and
protein levels were markedly more increased in 30-week-old ZDF rats than in age-matched ZLC group and in younger ZDF group.
The present study suggests that GR immunoreactivity and its protein level is associated with a degenerative phenotype in the
hypothalamus of from 12-weeks old in the ZDF rat type II diabetes model. 相似文献
7.
Hwang IK Yoo KY Yi SS Kwon YG Ahn YK Seong JK Lee IS Yoon YS Won MH 《Neurochemical research》2008,33(5):867-872
In the present study, we investigated age-related changes of newborn neurons in the gerbil dentate gyrus using doublecortin
(DCX), a marker of neuronal progenitors which differentiate into neurons in the brain. In the postnatal month 1 (PM 1) group,
DCX immunoreactivity was detected in the subgranular zone of the dentate gyrus, but DCX immunoreactive neurons did not have
fully developed processes. Thereafter, DCX immunoreactivity and its protein levels in the dentate gyrus were found to decrease
with age. Between PM 3 and PM 18, DCX immunoreactive neuronal progenitors showed well-developed processes which projected
to the granular layer of the dentate gyrus, but at PM 24, a few DCX immunoreactive neuronal progenitors were detected in the
subgranular zone of the dentate gyrus. DCX protein level in the dentate gyrus at PM 1 was high, thereafter levels of DCX were
decreased with time. The authors suggest that a decrease of DCX immunoreactivity and its protein level with age may be associated
with aging processes in the hippocampal dentate gyrus. 相似文献
8.
Dae Young Yoo Hyun Jung Kwon Kwon Young Lee Hyo Young Jung Jong Whi Kim Joon Ha Park 《Animal cells and systems.》2016,20(5):237-245
Transient forebrain ischemia promotes a robust increase in neuroblast differentiation in the hippocampal dentate gyrus that peaks 7–15 days after the surgery. In this study, we compared the glucose transporter 3 (GLUT3)-dependent glucose utilization and the dynamin-1 (DNM1)-dependent neurite growth in the hippocampus of Mongolian gerbils 15 days after the induction of transient forebrain ischemia. The animals were subjected to a 5 min transient ischemia protocol and sacrificed 15 days after the surgery. Both doublecortin (DCX) immunoreactive neuroblasts and DCX total protein levels were abundantly increased in the ischemic group compared to the levels observed in the control group. In addition, animals in the ischemic group showed elevated GLUT3 immunoreactivity in the subgranular zone of the dentate gyrus compared to animals in the control group. Based on the double immunofluorescent study, increased DCX-immunoreactive neuroblasts were co-localized with GLUT3-immunoreactive components in the dentate gyrus. However, both the immunoreactivity and the total protein levels of DNM1 were significantly decreased in the dentate gyrus and hippocampal CA1 regions of the ischemic group. These results suggest that the regeneration process such as neurite growth is lacking in the hippocampus 15 days after ischemia/reperfusion although neuroblasts production and glucose utilization increased in the hippocampus. 相似文献
9.
Hwang IK Yoo KY Li H Choi JH Kwon YG Ahn Y Lee IS Won MH 《Neurochemical research》2007,32(9):1604-1609
Doublecortin (DCX), a microtubule-associated protein, specifically expresses in neuronal precursors. This protein has been
used as a marker for neuronal precursors and neurogenesis. In the present study, we observed differences in DCX immunoreactivity
and its protein levels in the hippocampal dentate gyrus between adult and aged dogs. In the adult dog, DCX immunoreactive
cells with well-stained processes were detected in the subgranular zone of the dentate gyrus. Numbers of DCX immunoreactive
cells in the dentate gyrus of the aged dog were significantly decreased compared to those in the adult dog. DCX immunoreactive
cells in both adult and aged dog did not show NeuN (a marker for mature neurons) immunoreactivity. NeuN immunoreactivity in
the aged dog was poor compared to that in the adult dog. DCX protein level in the aged dentate gyrus was decreased by 80%
compared to that in the adult dog. These results suggest that the reduction of DCX in the aged hippocampal dentate gyrus may
be involved in some neural deficits related to the hippocampus. 相似文献
10.
Yi SS Hwang IK Kim YN Kim IY Pak SI Lee IS Seong JK Yoon YS 《Neurochemical research》2008,33(5):833-841
Arginine vasopressin (AVP) is known to a neuropeptide that plays important roles in water conservation, sodium homeostasis,
and in the regulation of serum osmolality. Several studies have reported that the elevated AVP level is related with diabetes
mellitus as an acute or chronic stressor using type 1 diabetes mellitus animal models. However, it is unclear as to how the
immunoreactivity and protein level of AVP in the brain is regulated in animal models of type 2 diabetes mellitus. In the present
study, Zucker diabetic fatty (ZDF) rats were employed as a type 2 diabetes mellitus model and were compared with Zucker lean
control (ZLC) rats with respect to AVP protein expression. Furthermore, in order to verify the regulation of AVP expression
before and after the onset of diabetes mellitus, pre-diabetic rats (4 week-old) and obese-diabetic rats (12 week-old) were
used. Blood glucose levels and water consumption were also measured and the results showed significantly high in 12 week-old
ZDF than any other groups. AVP expression levels in the paraventricular nucleus and supraoptic nucleus were found to be significantly
higher in 12 week-old ZDF rats than in 12 week-old ZLC rats and than in 4 week-old rats by immunostaining and western blotting.
Enhanced expression of AVP in these animals may be associated with type 2 diabetes mellitus.
Special issue article in honor of George Fink. 相似文献
11.
Complement inhibition reduces injury in the type 2 diabetic heart following ischemia and reperfusion
La Bonte LR Davis-Gorman G Stahl GL McDonagh PF 《American journal of physiology. Heart and circulatory physiology》2008,294(3):H1282-H1290
Chronic inflammation exacerbates the cardiovascular complications of diabetes. Complement activation plays an important role in the inflammatory response and is known to be involved in ischemia-reperfusion (I/R) injury in the nondiabetic heart. The purpose of this study was to determine if increased complement deposition explains, in part, the increased severity of neutrophil-mediated I/R injury in the type 2 diabetic heart. Nondiabetic Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats underwent 30 min of coronary artery occlusion followed by 120 min of reperfusion. Another group of ZDF rats was treated with the complement inhibitor FUT-175 before reperfusion. Left ventricular (LV) tissue samples were stained for complement deposition and neutrophil accumulation following reperfusion. We found significantly more complement deposition in the ZDF LV compared with the ZLC (P < 0.05), and complement deposition was associated with significantly greater neutrophil accumulation. In whole blood samples taken preischemia and at 120 min reperfusion, neutrophils exhibited significantly more CD11b expression in the ZDF group compared with the ZLC group (P < 0.05). Furthermore, intracellular adhesion molecule (ICAM)-1 expression following I/R was increased significantly in ZDF hearts compared with ZLC hearts (P < 0.001). These results indicate that, in the ZDF heart, increased ICAM-1 and polymorphonuclear neutrophil (PMN) CD11b expression play a role in increasing PMN accumulation following I/R. The infarct size of the ZDF was significantly greater than ZLC (P < 0.05), and treatment with FUT-175 significantly decreased infarct size, complement deposition, and PMN accumulation in the diabetic heart. These findings indicate an exacerbated inflammatory response in the type 2 diabetic heart that contributes to the increased tissue injury observed following ischemia and reperfusion. 相似文献
12.
Many patients with diabetes are not diagnosed at all or are diagnosed too late to be effectively treated, resulting in nonspecific symptoms and a long period of incubation of the disease. Pre-diabetes is an early warning signal of diabetes, and the change of urine glucose in this period has been ignored even though urine has long been related with diabetes. In this study, Zucker diabetic fatty (ZDF) rats were used to test if there were changes in urine glucose before blood glucose increases. Six 8-week-old male ZDF rats (fa/fa) and Zucker lean (ZL) rats (fa/+) were fed with Purina 5008 high-fat diet and tested for fasting blood glucose and urine glucose. After 12 weeks of feeding, the urine glucose values of the ZL rats were normal (0–10 mmol L~(-1)), but the values of the ZDF model rats increased 10 weeks before their blood glucose levels elevated. The urine glucose values of the ZDF model rats showed a state of disorder that was frequently elevated (10 mmol L~(-1)) and occasionally normal (0–10 mmol L~(-1)). This finding may provide an easy early screening for diabetes by long-term monitoring of urine glucose levels: pre-diabetes may be revealed by frequently disordered urine glucose levels over a period. 相似文献
13.
Yo Na Kim Sangok Kim Il-Yong Kim Jae Hoon Shin Sooyoung Cho Sun Shin Yi Wan Kyu Kim Kyung-Sub Kim Sanghyuk Lee Je Kyung Seong 《PloS one》2013,8(7)
Gene expression changes have been associated with type 2 diabetes mellitus (T2DM); however, the alterations are not fully understood. We investigated the effects of anti-diabetic drugs on gene expression in Zucker diabetic fatty (ZDF) rats using oligonucleotide microarray technology to identify gene expression changes occurring in T2DM. Global gene expression in the pancreas, adipose tissue, skeletal muscle, and liver was profiled from Zucker lean control (ZLC) and anti-diabetic drug treated ZDF rats compared with those in ZDF rats. We showed that anti-diabetic drugs regulate the expression of a large number of genes. We provided a more integrated view of the diabetic changes by examining the gene expression networks. The resulting sub-networks allowed us to identify several biological processes that were significantly enriched by the anti-diabetic drug treatment, including oxidative phosphorylation (OXPHOS), systemic lupus erythematous, and the chemokine signaling pathway. Among them, we found that white adipose tissue from ZDF rats showed decreased expression of a set of OXPHOS genes that were normalized by rosiglitazone treatment accompanied by rescued blood glucose levels. In conclusion, we suggest that alterations in OXPHOS gene expression in white adipose tissue may play a role in the pathogenesis and drug mediated recovery of T2DM through a comprehensive gene expression network study after multi-drug treatment of ZDF rats. 相似文献
14.
Hwang IK Yoo KY Yoo DY Choi JW Lee CH Choi JH Yoon YS Won MH 《Cellular and molecular neurobiology》2011,31(5):669-674
Cyclic AMP (cAMP) response element-binding protein (CREB) is involved in memory, learning, and synaptic transmission. In this
study, we observed changes of phosphorylated CREB (pCREB) immunoreactivity and its protein levels as well as brain-derived
neurotrophic factor (BDNF) levels in the hippocampal dentate gyrus at postnatal (P) 1, 7, 14, and 21 in mice. In addition,
we also investigated pCREB expression in doublecortin (DCX, a marker for neuronal progenitors) immunoreactive neuroblasts
at P21. pCREB immunoreaction at P1 was detected in most of cells in the dentate gyrus, thereafter pCREB immunoreactivity was
decreased in all the layers of the dentate gyrus with time, however, strong pCREB immunoreactivity was shown in cells confined
to the subgranular zone of the dentate gyrus at P21. In this group, many pCREB immunoreactive cells were co-localized with
DCX immunoreactive neuroblasts. In addition, pCREB protein levels were decreased with age, showing that their levels were
very low at P21, while BDNF protein levels were increased with age. These results suggest that pCREB may play important roles
in functional maturity of granule cells in mice. 相似文献
15.
Oltman CL Coppey LJ Gellett JS Davidson EP Lund DD Yorek MA 《American journal of physiology. Endocrinology and metabolism》2005,289(1):E113-E122
We have examined the progression of vascular and neural deficits in Zucker rats, Zucker diabetic fatty (ZDF) diabetic rats, and age-matched lean ZDF rats from 8 to 40 wk of age. Both the ZDF diabetic and Zucker rats were glucose intolerant at 8 wk of age. The Zucker rats did not become hyperglycemic but were hyperinsulinemic through 32 wk of age. All ZDF diabetic rats became hyperglycemic by 8 wk of age. Through their life span, serum free fatty acids and triglycerides levels were significantly higher in Zucker and ZDF diabetic rats compared with age-matched lean ZDF rats. After 24 and 28 wk of age, endoneurial blood flow was significantly decreased in ZDF diabetic and Zucker rats. Motor nerve conduction velocity was significantly decreased after 12-14 wk of age in ZDF diabetic rats and at 32 wk of age in Zucker rats. ACh-mediated vascular relaxation of epineurial arterioles of the sciatic nerve was impaired after 8-10 wk of age in ZDF diabetic rats and after approximately 16 wk of age in Zucker rats. In contrast, vascular relaxation mediated by calcitonin gene-related peptide was impaired significantly after 28 wk of age in ZDF diabetic rats but not impaired in Zucker rats up to 40 wk of age. Markers of oxidative stress were differentially elevated in ZDF diabetic rats and Zucker rats. These data indicate that vascular and neural dysfunction develops in both Zucker and ZDF diabetic rats but at different rates, which may be the result of hyperglycemia. 相似文献
16.
Hee-Jae Kim Byunghun So Jun Seok Son Han Sol Song Seung Lyul Oh Je Kyung Seong Hoyoung Lee Wook Song 《Journal of Exercise Nutrition & Biochemistry》2015,19(4):281-288
[Purpose]
In the present study, we investigated the effects of 8 weeks of progressive resistance training on the level of skeletal muscle derived BDNF as well as glucose intolerance in Zucker diabetic rats.[Methods]
Six week-old male Zucker diabetic fatty (ZDF) and Zucker lean control (ZLC) rats were randomly divided into 3 groups: sedentary ZLC (ZLC-Con), sedentary ZDF (ZDF-Con), and exercised ZDF (ZDF-Ex). Progressive resistance training using a ladder and tail weights was performed for 8 weeks (3 days/week).[Results]
After 8 weeks of resistance training, substantial reduction in body weight was observed in ZDF-Ex compared to ZDF-Con. Though the skeletal muscle volume did not change, grip strength grip strength was significantly higher in ZDF-Ex compared to ZDF-Con. In the soleus, the level of BDNF was increased in ZDF-Con, but was significantly decreased (p<0.05) in ZDF-Ex, showing a training effect. Moreover, we found that there was a negative correlation (r=-0.657; p=0.004) between grip strength and BDNF level whereas there was a positive correlation (r=0.612; p=0.008) between plasma glucose level and BDNF level in skeletal muscle.[Conclusion]
Based upon our results, we demonstrated that resistance training inhibited the elevation of skeletal muscle derived-BDNF expression concomitant with the improvement of muscle strength in zucker diabetic rats. In addition, muscle-derived BDNF might be a potential mediator for the preventive effect of resistance training on the progress of type 2 diabetes. 相似文献17.
Pelzer T Jazbutyte V Arias-Loza PA Segerer S Lichtenwald M Law MP Schäfers M Ertl G Neyses L 《Biochemical and biophysical research communications》2005,329(2):726-732
Peroxisome proliferator-activated receptor-gamma (PPARgamma) plays a critical role in peripheral glucose homeostasis and energy metabolism, and inhibits cardiac hypertrophy in non-diabetic animal models. The functional role of PPARgamma in the diabetic heart, however, is not fully understood. Therefore, we analyzed cardiac gene expression, metabolic control, and cardiac glucose uptake in male Zucker diabetic fatty rats (ZDF fa/fa) and lean ZDF rats (+/+) treated with the high affinity PPARgamma agonist pioglitazone or placebo from 12 to 24 weeks of age. Hyperglycemia, hyperinsulinemia, and hypertriglyceridemia as well as lower cardiac PPARgamma, glucose transporter-4 and alpha-myosin heavy chain expression levels were detected in diabetic ZDF rats compared to lean animals. Pioglitazone increased body weight and improved metabolic control, cardiac PPARgamma, glut-4, and alpha-MHC expression levels in diabetic ZDF rats. Cardiac [(18)F]fluorodeoxyglucose uptake was not detectable by micro-PET studies in untreated and pioglitazone treated ZDF fa/fa rats but was observed after administration of insulin to pioglitazone treated ZDF fa/fa rats. PPARgamma agonists favorably affect cardiac gene expression in type-2 diabetic rats via activation and up-regulation of cardiac PPARgamma expression whereas improvement of impaired cardiac glucose uptake in advanced type-2 diabetes requires co-administration of insulin. 相似文献
18.
Choi JH Yoo KY Lee CH Yi SS Yoo DY Seong JK Yoon YS Hwang IK Won MH 《Cellular and molecular neurobiology》2011,31(2):285-292
N-methyl-d-aspartate receptor (NR) is involved in activity-dependent synaptic plasticity, such as associative long-term potentiation,
and in related central functions, such as learning and memory. In this study, we observed effects of treadmill exercise on
NR1 and doublecortin (DCX, a marker for neuroblast differentiation) in the subgranular zone of the dentate gyrus (DG). At
6 weeks of age, rats were put on a treadmill with or without running for 1 h/day for 5 consecutive days at 22 m/min for 5 weeks.
Exercise increased NR1 immunoreactivity and protein level in the hippocampus. To identify the correlations between NR and
neuroblasts, we intraperitoneally administered a NR antagonist, MK-801, to the exercised rats. MK-801 treatment reduced NR1
protein level in the hippocampus of the exercised rats. In addition, in the MK-801-treated group, the number of DCX cells
was significantly decreased in the subgranular zone of the DG. These results suggest that NR may be one of the important factors
that modulate neuroblast differentiation during exercise in rats. 相似文献
19.
Male obese Zucker Diabetic Fatty (ZDF) rats develop type 2 diabetes around eight weeks of age, and are widely used as a model for human diabetes and its complications. The objective of the study was to test whether the complications manifested in the kidney and nerves of ZDF rats really correspond to human diabetic complications in their being related to the hyperglycaemic state. Four groups of ZDF rats were used. One lean (Fa/?) and one obese (fa/fa) untreated group served as non-diabetic and diabetic controls. In two further groups of obese (fa/fa) rats, diabetes was prevented by pioglitazone or delayed by food restriction. All rats were monitored up to 35 weeks of age with respect to their blood glucose, HbA1c and insulin levels, their kidney function (urinary glucose excretion, renal glucose filtration, glomerular filtration rate, albumin/creatinine ratio), and their nerve function (tactile and thermal sensory threshold and nerve conduction velocity). Pioglitazone prevented the development of diabetes, while food restriction delayed its onset for 8-10 weeks. Accordingly, kidney function parameters were similar to lean non-diabetic rats in pioglitazone-treated rats and significantly improved in food-restricted rats compared with obese controls. Kidney histology paralleled the functional results. By contrast, nerve functional evaluations did not mirror the differing blood glucose levels. We conclude that the ZDF rat is a good model for diabetic nephropathy, while alterations in nerve functions were not diabetes-related. 相似文献
20.
Kishor M. Wasan Verica Risovic Violet G. Yuen John H. McNeill 《Journal of trace elements in medicine and biology》2006,19(4):251-258
PURPOSE: Recently, our laboratory group has reported that rats with Type 1 diabetes have decreased plasma homocysteine and cysteine levels compared to non-diabetic controls and that organic vanadium treatment increased plasma homocysteine concentrations to non-diabetic concentrations. However, to date, no studies have been done investigating the effects of organic vanadium compounds on plasma homocysteine and its metabolites in Type 2 diabetic animal model. These studies examined the effect of organic vanadium compounds [bis(maltolato)oxovanadium(IV) and bis(ethylmaltolato)oxovanadium(IV); BMOV and BEOV] administered orally on plasma concentrations of homocysteine and its metabolites (cysteine and cysteinylglycine) in lean, Zucker fatty (ZF) and Zucker diabetic fatty (ZDF) rats. ZF rats are a model of pre-diabetic Type 2 diabetes characterized by hyperinsulinemia and normoglycemia. The ZDF rat is a model of Type 2 diabetes characterized by relative hypoinsulinemia and hyperglycemia. METHODS: Zucker lean and ZF rats received BMOV in the drinking water at a dose of 0.19 +/- 0.02 mmol/kg/day. Lean and ZDF rats received BEOV by oral gavage daily at dose of 0.1 mmol/kg. The treatment period for both studies was 21 days. At termination, animals were fasted overnight (approximately 16 h) and blood samples were collected by cardiac puncture for determination of plasma glucose, insulin and homocysteine levels. Plasma homocysteine and its metabolites levels were determined using high-pressure liquid chromatography. Plasma glucose was determined using a Glucose Analyzer 2. Plasma insulin levels were determined by radioimmunoassay. Plasma triglycerides were determined by an enzymatic assay methodology. RESULTS: ZF (n = 4) and ZDF (n = 10) rats had significantly lower plasma homocysteine as compared to their respective lean groups (ZF 0.78 +/- 0.1 micromol/L vs. Zucker lean 2.19 +/- 0.7 micromol/L; ZDF 1.71 +/- 0.2 micromol/L vs. Zucker lean 3.02 +/- 0.3 micromol/L; p < 0.05). BMOV treatment in ZF rats restored plasma homocysteine levels to those observed in lean untreated rats (ZF treated: 2.04 +/- 0.2 micromol/L; lean 2.19 +/- 0.7 micromol/L). There was a modest effect of BMOV treatment on plasma glucose levels in ZF rats. BEOV treatment significantly decreased the elevated plasma glucose levels in the ZDF rats (lean 7.9 +/- 0.1 mmol/L; lean + vanadium 7.7 +/- 0.2 mmol/L; ZDF 29.9 +/- 0.4 mmol/L; ZDF + vanadium 17.4 +/- 0.3 mmol/L, p < 0.05). Organic vanadium treatment reduced cysteine levels in both ZF and ZDF rats. No differences in total plasma cysteinylglycine concentrations were observed. CONCLUSION: Plasma homocysteine levels are significantly reduced in a pre-diabetic model of Type 2 diabetes, which was restored to lean levels upon vanadium treatment; however, this restoration of plasma homocysteine levels was not seen in ZDF Type 2 diabetic rats following vanadium treatment. In the latter case vanadium treatment may not have totally overcome the insulin resistance seen in these animals. 相似文献