Wyniki wyszukiwania

1

Changes in midgut and brain proteins in Morimus funereus larvae depending on nutritive substrate

100%

Ilijin L., Jankovic-Tomanic M., Mitic M., Vlahovic M., Lazarevic J., Peric-Mataruga V., Prolic Z., Nenadovic V.

Folia Biologica

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2003

|

tom 51

|

nr 3-4

2

Changes in estrogen receptor ERalpfa and ERbeta expression in chicken (Gallus domesticus) adrenal gland during short-fasting and refeeding

84%

Blachuta M., Wronska-Fortuna D.

Folia Biologica

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2012

|

tom 60

|

nr 3-4

3

Short-term calorie restriction and refeeding differently affect lipogenic enzymes in major white adipose tissue depots of young and old rats

84%

Wronska A., Sledzinski T., Goyke E., Lawniczak A., Wierzbicki P., Kmiec Z.

Journal of Physiology and Pharmacology

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2014

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tom 65

|

nr 1

4

The effects of fasting and refeeding on adrenal cortex morphometry and serum concentrations of ACTH and corticosterone in young and old male rats

84%

Kmiec Z., Pokrywka L., Kotlarz G., Mysliwski A.

Journal of Physiology and Pharmacology. Supplement

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2006

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tom 57

|

nr 6

77-84

The impairment of homeostatic mechanisms in ageing becomes often apparent upon physiological or pathological stimulation. We have previously shown that fasting and refeeding revealed the existence of age-related changes of carbohydrate and lipid metabolism. Because fuel metabolism is partially controlled by corticosteroids we decided to determine the effects of refeeding on adrenal gland morphometry, ACTH, and corticosterone serum levels in young (5 mo) and (20 mo) old male Wistar rats. Fasting for 48 h did not change serum ACTH and corticosterone in both age groups. ACTH level did not change after 24 h of refeeding in young and old rats. However, in old, but not young animals, refeeding resulted in the decrease of corticosterone serum concentration. The relative weight of adrenal gland (% of body weight) did not change significantly with age (p=0.05). Fasting for 48 h induced in old rats but not in young ones increase of relative adrenal weight, and the volume of the reticular zone. Refeeding reduced adrenal volume, fascicular zone and reticular zone. Refeeding for 24 h decreased the total volume of adrenal gland of old rats due to a decline of the volumes of fascicular and reticular zones. In young rats refeeding reduced the volume of reticular zone. It is concluded that refeeding revealed ageing-dependent decline in the secretion of corticosterone, the key hormone of prolonged stress response.

5

Tissue-specific effect of refeeding after short- and long-term caloric restriction on malic enzyme gene expression in rat tissues

84%

Stelmanska E., Korczynska J., Swierczynski J.

Acta Biochimica Polonica

|

2004

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tom 51

|

nr 3

Restricting food intake to a level below that consumed voluntarily (85%, 70% and 50% of the ad libitum energy intake for 3 or 30 days) and re-feeding ad libitum for 48 h results in an increase of malic enzyme (ME) gene expression in rat white adipose tissue. The increase of ME gene expression was much more pronounced in rats maintained on restricted diet for 30 days than for 3 days. The changes in ME gene expression resembled the changes in the content of SREBP-1 in white adipose tissue. A similar increase of serum insulin concentration was observed in all groups at different degrees of caloric restriction and refed ad libitum for 48 h. Caloric restriction and refeeding caused on increase of ME activity also in brown adipose tissue (BAT) and liver. However, in liver a significant increase of ME activity was found only in rats maintained on the restricted diet for 30 days. No significant changes after caloric restriction and refeeding were found in heart, skeletal muscle, kidney cortex, and brain. These data indicate that the increase of ME gene expression after caloric re- striction/refeeding occurs only in lipogenic tissues. Thus, one can conclude that caloric restriction/refeeding increases the enzymatic capacity for fatty acid biosynthesis.

6

The effect of fasting and refeeding on the ultrastructure of the hypothalamic paraventricular nucleus in young and old rats

84%

Kubasik-Juraniec J., Kmiec Z., Tukaj C., Rudzinska-Kisiel T., Kotlarz G., Pokrywka L., Mysliwski A.

Folia Morphologica

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2004

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tom 63

|

nr 1

In order to explore the morphological basis of the altered feeding behaviour of old rats, an ultrastructural investigation of the magnocellular neurons of the hypothalamic paraventricular nucleus (PVN) was performed. Young and old male Wistar rats, 5 and 24 months old, respectively, and with each age group comprising 12 animals, were divided into 3 groups. The rats in Group I were used as controls (normally fed), the rats of Group II were fasted for 48 hours and in Group III the rats were fasted for 48 hours and then refed for 24 hours. The brains were fixed by perfusion and histological and ultrathin sections were obtained by routine methods. Common features of the magnocellular PVN neurons of young and old rats were abundant Golgi complexes and short fragments of RER localised at the cell periphery. In contrast to young rats, the PVN neurons of old animals showed deep indentations of the nuclear envelope and agerelated residual bodies. In both age groups fasting for 48 hours led to the expansion of the Golgi complexes and dilatation of RER cisternae. In contrast to those in fed rats, RER cisternae in the neurons of old fasted animals were situated between the nuclear envelope and the Golgi zone. Prolonged RER cisternae were distributed in the peripheral cytoplasm of refed old rats. Our observations suggest that at the ultrastructural level the process of ageing does not change the responsiveness of magnocellular PVN neurons to fasting-refeeding.

7

Thyroid C cell function during fasting and refeeding of young and old rats

84%

Kmiec Z., Kotlarz G., Mysliwski A., Wyrzykowska M., Pokrywka L.

Folia Histochemica et Cytobiologica

|

2002

|

tom 40

|

nr 2

8

The effects of weight cycling on serum leptin levels and lipogenic enzyme activities in adipose tissue

67%

Kochan Z., Karbowska J., Swierczynski J.

Journal of Physiology and Pharmacology. Supplement

|

2006

|

tom 57

|

nr 6

115-127

Weight cycling is one of the widely used weight reduction strategies; however, the adverse effects of this method include regaining significant amounts of weight. The molecular mechanisms underlying weight gain following cycles of dietary deprivation and refeeding are still poorly understood. One of the possibilities is that repeated loss and gain of weight may promote fat deposition in adipose tissue. To test this hypothesis we investigated serum leptin levels and lipogenic enzyme activities in white adipose tissue (WAT) of male Wistar rats during 12 days of ad libitum feeding following multiple cycles of alternating food deprivation and refeeding. Rats subjected to eight cycles of food deprivation and refeeding (MFR group) showed significantly decreased circulating leptin levels when compared with control rats (nearly 50% decrease in leptin levels, P < 0.01). Throughout 12 days of ad libitum feeding, serum leptin levels increased modestly but remained significantly (24%, P < 0.05) lower than control levels. Fatty acid synthase (FAS) and malic enzyme (ME) activities (chosen as representatives of enzymes directly involved in fatty acid synthesis) were found to be considerably higher in WAT of MFR rats refed for 3 days in comparison to control rats, and remained elevated even after 12 days of refeeding. These observations suggest that the elevation of lipogenic enzyme activities induced by multiple cycles of dietary deprivation followed by refeeding persists for several days, markedly increasing the lipogenic capacity of adipose tissue, which, accompanied by a decrease in circulating leptin levels, may promote weight gain.

9

Ultrastructure of the ventromedial hypothalamic nucleus in fasted and refed young and old rats

67%

Kubasik-Juraniec J., Kmiec Z., Tukaj C., Adamowska A., Kotlarz G., Pokrywka L., Mysliwski A.

Folia Morphologica

|

2003

|

tom 62

|

nr 2

Many hypothalamic nuclei are involved in the regulation of food intake and energy homeostasis. An ultrastructural investigation of the hypothalamic ventromedial nucleus (VMN), a hypothetical “satiety centre” was performed to explore the morphological basis of altered feeding behaviour of old rats in an experimental model of fasting/refeeding. Young (5 months old, n = 12) and old (24 months old, n = 12) male Wistar rats were fasted for 48 hours, then refed for 24 hours and sampled thereafter. Brain tissue was fixed by perfusion, histological and ultrathin sections were obtained by routine methods. Although food intake was similar in control young and old rats, during refeeding old animals consumed less chow than young ones. The EM analysis of VMN neurones of old control rats revealed, besides typical age-related residual bodies, deep indentations of the nuclear envelope and the presence of long, undulating rough endoplasmic reticulum cisternae in the cell periphery. In both young and old rats fasting for 48 hours led to the expansion of Golgi complexes and increased folds of the nuclear envelope, which is suggestive of enhanced cellular activity of the VMN neurones. These fasting-induced alterations were sustained in the VMN neurones of refed rats in both age groups. The results showed that the VMN neurones of old control rats differ at the ultrastructural level from young ones. However, starvation and subsequent refeeding cause similar alterations in the hypothalamic neurones of “satiety centre” of both young and old rats.

Ograniczanie wyników

Changes in midgut and brain proteins in Morimus funereus larvae depending on nutritive substrate

Changes in estrogen receptor ERalpfa and ERbeta expression in chicken (Gallus domesticus) adrenal gland during short-fasting and refeeding

Short-term calorie restriction and refeeding differently affect lipogenic enzymes in major white adipose tissue depots of young and old rats

The effects of fasting and refeeding on adrenal cortex morphometry and serum concentrations of ACTH and corticosterone in young and old male rats

Tissue-specific effect of refeeding after short- and long-term caloric restriction on malic enzyme gene expression in rat tissues

The effect of fasting and refeeding on the ultrastructure of the hypothalamic paraventricular nucleus in young and old rats

Thyroid C cell function during fasting and refeeding of young and old rats

The effects of weight cycling on serum leptin levels and lipogenic enzyme activities in adipose tissue

Ultrastructure of the ventromedial hypothalamic nucleus in fasted and refed young and old rats