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1

Coenzyme Q releases the inhibitory effect of free fatty acids on mitochondrial glycerophosphate dehydrogenase

100%

Rauchova H., Drahota Z., Rauch P., Fato R., Lenaz G.

Acta Biochimica Polonica

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2003

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tom 50

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nr 2

Data presented in this paper show that the size of the endogenous coenzyme Q (CoQ) pool is not a limiting factor in the activation of mitochondrial glyceropho- sphate-dependent respiration by exogenous CoQ3, since successive additions of succinate and NADH to brown adipose tissue mitochondria further increase the rate of oxygen uptake. Because the inhibition of glycerophosphate-dependent respiration by oleate was eliminated by added CoQ3, our data indicate that the activating effect of CoQ3 is related to the release of the inhibitory effect of endogenous free fatty acids (FFA). Both the inhibitory effect of FFA and the activating effect of CoQ3 could be demonstrated only for glycerophosphate-dependent respiration, while succinate- or NADH-dependent respiration was not affected. The presented data suggest differences between mitochondrial glycerophosphate dehydrogenase and succinate or NADH dehydrogenases in the transfer of reducing equivalents to the CoQ pool.

2

Seasonal and photoperiodic effects on lipid droplet size and lipid peroxidation in the brown adipose tissue of bank voles (Myodes glareolus)

84%

Bonda-Ostaszewska E., Wlostowski T., Krasowska A., Kozlowski P.

Acta Theriologica

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2012

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tom 57

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nr 4

Seasonal changes in lipid droplet size and lipid peroxidation in the brown adipose tissue (BAT) of wild bank voles were examined. In addition, a role of photoperiod in these changes was studied; bank voles were held from the birth under long photoperiod (LP) for 12 weeks, and then half of them was transferred to short photoperiod (SP) for 6 weeks and another one remained under LP. In the wild bank voles the absolute BAT weight was seasonally constant, while the significant differences in the lipid droplet size were observed. The smallest lipid droplets (mean, 11 μm2) were seen in winter; they increased by 30 % in spring and reached the highest size (24 μm2) in summer. Lipid peroxidation in the BAT did not differ significantly between the seasons, although high intraseason variation of this process was noted. The laboratory experiment revealed that the size of lipid droplets was determined by photoperiod; SP induced 13-fold decrease, and continuous exposure to LP brought about a further 2.5-fold increase in the size of lipid droplets. Conversely, a significant decrease in lipid peroxidation was seen in LP bank voles in comparison with the SP animals. The data indicate that short photoperiod is responsible for the small size of lipid droplets in the BAT of bank voles during winter, which may be a necessary requirement for high thermogenic capacity of the tissue. Photoperiod appears also to affect lipid peroxidation in the BAT of these animals.

3

Maximizing survivorship in cold: thermogenic profiles of non-hibernating mammals

84%

Merritt J. F., Zegers D. A.

Acta Theriologica. Supplement

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2002

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tom 47

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nr 1

Winter-active small mammals residing in seasonal environments employ many different behavioral, anatomical and physiological mechanisms to cope with cold. Herein we review research on survival mechanisms in cold employed by small mammals with emphasis on the families Soricidae, Muridae and Sciuridae. The focus of this review is on research delineating the role of seasonal changes in resting metabolic rate (RMR), nonshivering thermogenesis (NST), body mass, and communal nesting in enhancing winter survivorship of six species of small mammals (masked shrew Sorex cinereus, short-tailed shrew Blarina brevicauda, southern red-backed vole Clethrionomys gapperi, white-footed mouse Peromyscus leucopus, deer mouse P. maniculatus, and southern flying squirrel Glaucomys volans) residing in the Appalachian Mountains of Pennsylvania, USA. Each species shows good over-winter survivorship but exhibits a different suite of mechanisms to maximize survival in cold. B. brevicauda, S. cinereus, and G. volans show slight increases in RMR during winter, whereas Peromyscus and C. gapperi exhibit decreased RMR overwinter. All six species experience elevated NST in winter. The comparatively low RMR and NST of G. volans during winter was attributable to a decreased energy expenditure due to a larger body mass, coupled with communal nesting in cavities of trees that provided insulation from low ambient temperatures. Squirrels nesting singly experienced a longer period of elevated NST in winter and higher mean NST year-round than did squirrels nesting communally. Energy conservation in the form of growth retardation in winter was exhibited by C. gapperi and S. cinereus but not the other species.

4

Leptin immunoexpression and innervation in rat interscapular brown adipose tissue of cold-acclimated rats: the effects of L-arginine and L-NAME

67%

Korac A., Buzadzic B., Petrovic V., Vasilijevic A., Jankovic A., Korac B.

Folia Histochemica et Cytobiologica

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2008

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tom 46

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nr 1

103-109

5

Morphological characteristics of neonatal adipose tissue

67%

Atanassova P., Rancic G., Georgieva E.

Folia Biologica

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2012

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tom 60

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nr 1-2

6

Influence of potent and selective beta-adrenoreceptor agonist, CL 316243, on the contractile response of non-pregnant human myometrium

67%

Pedzinska-Betiuk A., Modzelewska B., Kostrzewska A., Jozwik M.

Journal of Physiology and Pharmacology. Supplement

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2008

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tom 59

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nr 9

43-54

7

The thyroid gland brown adipose tissue of forest mice and bank voles over the annual cycle

67%

Sawicki B.

Folia Morphologica

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1998

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