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Serbian spruce (Picea omorika (Pancic) Purk.) is tertiary relict and endemic species with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Serbian spruce has been on The International Union for Conservation of Nature's Red List (IUCN) of Threatened Species since 1998. In the beginning it was marked as a vulnerable species and since 2010 as an endangered species. Serbian spruce is a tree species which has a wide ecological aspect in relation to the basic ecological factors, and the forest associations that were the subject of this research are among the most valuable forest associations in the region. The research described in this paper conducted with an aim to define the type of forests that contain Serbian spruce as an edifier in the area of mountain Radava in the Republic of Srpska (Bosnia and Herzegovina) in order to genetically preserve this rare and endangered tree species from the Balkans. Based on the research of ecological factors of habitats and the definition of production stand characteristics, the production type of forest was singled out - Forest type of European beech, silver fir, Norway spruce and Serbian spruce (Piceo omorikae-Abietetum [5]) on a series of soils on limestone. [ABSTRACT FROM AUTHOR]

Background: The effect of insulin on the endocrine pancreas has been the subject of extensive study, but quantitative morphometric investigations of the exocrine pancreas are scarce. This study was therefore undertaken to investigate the effect of acute and chronic insulin administration (two doses, 0.4 IU and 4 IU) on the morphology of rat pancreas acini.Materials and Methods: Semi-fine sections stained with methylene blue and basic fuchsine or haematoxylin and eosin-stained 5-micrometer thick paraffin sections were used for fractal and stereological analysis of exocrine acini. Acute insulin treatment, independent of applied doses increased fractal dimension in line with decreased lacunarity of pancreas acini. Chronic low dose insulin decreased fractal dimension and increased lacunarity of pancreas acini, but a high dose had the opposite effect. The volume densities (Vv) of cytoplasm, granules and nucleus are affected differently: acute low dose and high chronic dose significantly decreased granules Vv, and in line increased cytoplasmic Vv, whereas other examined structures showed slight changes without statistical significance.Results: The results obtained from this investigation indicate that insulin treatment induced structural remodelling of the exocrine pancreas suggesting a substantial role of insulin in its functioning.Conclusions: Additionally, we showed that fine architectural changes in acini could be detected by fractal analysis, suggesting this method as an alternative or addition to routine stereology. [ABSTRACT FROM AUTHOR]

The increased ambient temperature affects the function of hypothalamic-pituitary-adrenal (HPA) axis. Since the correlation among vasopressin (VP), adrenocorticotropic hormone (ACTH) and corticosterone (CORT) responses to various stressors have been long recognized, the aim of this study was to reveal the aforementioned hormones production and morphology of the pituitary gland after exposure to acute heat. Rats were exposed to high ambient temperature (38°C) for 20 or 60 minutes. The circulating hormones were determined by an ELISA test or chemiluminescence's method. The results obtained show the elevation in ACTH and CORT secretion depending on the duration of heat exposure. The VP concentration increased only after prolonged exposure to heat (60 min). The pituitary morphology was examined by routine and fluorescent immunohistochemistry as well as electron microscopy. Observed changes in the anterior and posterior pituitary well corresponded to circulating hormones, regarding the volume density of ACTH-immunopositive cells, percentage of ACTH immunopositive area v. total area and number of VP-immunopositive containing varicose fibers per total area. Acute heat exposure also induced changes in shapes of ACTH-immunopositive cells. Cells appeared stellate with numerous slender cytoplasmic processes and degranulated, which is the most obvious after 20 min. In addition, immunopositivity of endothelial and anterior pituitary cells for VP suggests its influence on ACTH secretion. [ABSTRACT FROM AUTHOR]

Sirtuin 1 (SIRT1), a conserved member of the family of the silencing information regulator 2 enzymes called sirtuins, is a NAD+ dependent deacetylase, and a key mediator of lifespan, and metabolism [1]. Melatonin, the pineal indolamine, is a potent SIRT1 activator which alleviates the cardiometabolic syndrome in genetically obese leptin-deficient mice [2]. Here, to best characterize its role in dietary obesity, we analysed morphological changes induced in whole body SIRT1 heterozygous mice (HET) on a high fat diet (58.4% E from fat-lard TD03584-Envigo) vs mice on standard maintenance rodent diet (8.4% E from fat). Male wildtype C57BL6/J mice (WT) were placed on above regimens for comparison. HET and WT mice received a standard diet (STD) or a high fat (HFD) diet for 16 weeks and melatonin, in drinking water at 10 mg/kg/day. Cardiac reaction to the hypercaloric lard diet was characterized analysing inter-myofibrillary mitochondria, fibrosis, lipid peroxidation, inflammation, and endoplasmic reticulum stress. Remarkably, round mitochondria with abnormal cristae, fibrosis and inflammation were exacerbated in HET HFD despite melatonin. Oxidative damage, endoplasmic reticulum stress and inflammation have been validated by strong 4HNE, GRP78, CHOP and NLRP3 immunostaining. Unfortunately, melatonin failed to improve cardiac alterations in HET HFD group. These data highlight the strict interdependence between melatonin and SIRT1 in the treatment of cardiac complications in obesity. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate lipofuscin origin in brown adipocytes of hyperinsulinaemic rats and the possible role of lipid peroxidation and iron in this process. Ultrastructural examination revealed hyperinsulinaemia-induced enhancement in the lipofuscin production, accompanied by an increase of mitochondrial damage in brown adipocytes. Extensive fusions of lipid droplets and mitochondria with lysosomes were also observed. Confocal microscopy showed lipofuscin autofluorescence emission in brown adipose tissue (BAT) after excitation at 488 nm and 633 nm, particularly in the insulin-treated groups. The presence and distribution of lipid peroxidation product, 4-hydroxy-2-nonenal (4-HNE), in brown adipocytes was assessed by immunohistochemical examination revealing its higher content after treatment with insulin. The iron content was quantified by electron dispersive X-ray analysis (EDX) showing its higher content in the hyperinsulinaemic groups. The ultrastucture of the majority of lipofuscin granules suggests their mitochondrial origin, which was additionally confirmed by their co-localization with ATP synthase. In conclusion, our results suggest that increased lipofuscinogenesis in the brown adipocytes of hyperinsulinaemic rats is a consequence of lipid peroxidation, mitochondrial damage and iron accumulation.