Saška Lipovšek

• PhD
• University of Maribor

Autophagy is a highly conserved metabolic process that regulates cellular homeostasis and energy supply by degrading dysfunctional and excess cell constituents and reserve materials into products that are reused in metabolic and biosynthetic pathways. Macroautophagy is the best studied form of autophagy in invertebrates. Starvation is a common stre...

Mouse models of diet-induced type 2 diabetes mellitus provide powerful tools for studying the structural and physiological changes that are related to the disease progression. In this study, diabetic-like glucose dysregulation was induced in mice by feeding them a western diet, and light and transmission electron microscopy were used to study the u...

Most subterranean habitats, especially caves, are considered extreme environments, mainlybecause of the limited and erratic food supply and constant darkness. In temperate regions, manyclimatic conditions, such as temperature and air humidity, are periodically less adverse or even morefavourable in caves than the harsh seasonal weather on the surfa...

Iron is known to accumulate in neurological disorders, so a careful balance of the iron concentration is essential for healthy brain functioning. An imbalance in iron homeostasis could arise due to the dysfunction of proteins involved in iron homeostasis. Here, we focus on ferritin—the primary iron storage protein of the brain. In this study, we ai...

The physiology and pathophysiology of the exocrine pancreas are in close connection to changes in intra-cellular Ca²⁺ concentration. Most of our knowledge is based on in vitro experiments on acinar cells or acini enzymatically isolated from their surroundings, which can alter their structure, physiology, and limit our understanding. Due to these li...

Insulin resistance in key target organs and beta cell dysfunction due to gluco- and lipotoxicity, are the two main factors driving type 2 diabetes mellitus pathogenesis. Recently, it has been suggested that ectopic fat deposition in the pancreas, named non-alcoholic fatty pancreas disease, occurs in metabolic syndrome, and may play an etiological r...

Iron is known to accumulate in neurological disorders, so a careful balance of the iron concentration is essential for healthy brain functioning. An imbalance in iron homeostasis could arise due to the dysfunction of the proteins involved in iron homeostasis. Here, we focus on ferritin – the primary iron storage protein of the brain. Though it is k...

Amilenus aurantiacus overwinter in diapause, a natural starvation period, in hypogean habitats. The structure of spherites in the midgut diverticula (MD) and Malpighian tubules (MT) has been studied comparatively by light microscopy and TEM to detect eventual differences in mineral consumption in the beginning and at the end of the starvation perio...

Purpose: Toxin B (TcdB) is a product of the bacteria Clostridium difficile, and can trigger apoptosis or necrosis. In the present manuscript, we proposed that TcdBVPI and TcdB8864 would cause morphological changes in cultured cells that are characteristic of autophagy, a constitutive cellular event closely linked with apoptosis or necrosis. Methods...

Nemastoma bidentatum Roewer, 1914 is a complex of closely related litter-dwelling harvestmen, characterized by a penis glans with two pairs of lateral lancet-like spines, and a femur IV with a saw-like series of pointed tubercles. Here we a) revise the hitherto known taxa within the N. bidentatum complex, and b) analyze in detail the relations amon...

In arachnids, the Malpighian tubules (MTs), coxal glands and stercoral pockets are capable of collecting and removing excreta from the body. The presence of the MTs among Opiliones was evidenced for the first time in Amilenus aurantiacus in 2015. Individuals undergo a winter diapause subterranean habitats. Here, we provided the morphological and cy...

Two closely related, syntopic species, Leiobunum rupestre and L. subalpinum, spend the day at apparently randomly distributed resting sites. In this preliminary research, we studied differences in their microclimatic preferences at a locality in the Pohorje Mts., Slovenia. We measured air temperature and relative humidity at individual resting site...

Navodila za vaje so razdeljena na 13 poglavij in obravnavajo vse teme s področja biologije celice za študente medicine.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monit...

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monit...

Navodila za vaje obsegajo osem poglavij s področja glavnih vsebin biologije celice (struktura in funkcija celic).

the PDF can be download freely on pubmed. https://pubmed.ncbi.nlm.nih.gov/33634751/

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monit...

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monit...

Article Open Access Published: 14 February 2020 A Novel in situ Approach to Studying Detrusor Smooth Muscle Cells in Mice Tamara Serdinšek, Saša Lipovšek, Gerd Leitinger, Igor But, Andraž Stožer & Jurij Dolenšek Scientific Reports volume 10, Article number: 2685 (2020) Cite this article Abstract The aim of our study was to develop a novel approac...

Type 2 diabetes mellitus (T2DM) has been associated with insulin resistance and the failure of β-cells to produce and secrete enough insulin as the disease progresses. However, clinical treatments based solely on insulin secretion and action have had limited success. The focus is therefore shifting towards α-cells, in particular to the dysregulated...

Electron microscopy (EM) provides the necessary resolution to visualize the finer structures of nervous tissue morphology, which is important to understand healthy and pathological conditions in the brain. However, for the interpretation of the micrographs the tissue preservation is crucial. The quality of the tissue structure is mostly influenced...

The European cave spider, Meta menardi, is a representative of the troglophiles, i.e. non-strictly subterranean organisms. Our aim was to interpret the cytological results from an ecological perspective, and provide a synthesis of the hitherto knowledge about M. menardi into a theory of key features marking it a troglophile. We studied ultrastructu...

The behavior, metabolism and physiology of animals are regulated by seasonal and/or circadian rhythms. The main aim of this study was to describe all of the alterations that are connected with the structure, ultrastructure and histochemistry in the fat body according to the seasonal cycles in centipedes. We selected the common European and long-liv...

The European cave spider, Meta menardi, is among the most common troglophile species inhabiting the cave entrance zone in Europe, where prey is scarce in winter. Spiders feed only if prey is available; otherwise, they are subjected to long-term winter starvation. We carried out a four-month winter starvation of M. menardi under controlled condition...

During the growth period, in surface habitats, spiders catch enough prey to feed normally. In contrast, in the cave entrance zone, prey may be relatively scarce. Meta menardi inhabits this cave section, resulting in temporary starvation. We studied structural changes in the midgut epithelial cells of M. menardi during a short-term and a medium-term...

Front Cover: High internal phase emulsions containing monomers are placed in prefabricated solid sphere templates, polymerised and extracted in order to obtain hierarchically macroporous polymer with an interconnected porous topology. Human osteoblast cells are seeded on the material and growth and proliferation into the bulk of material is evident...

A combination of hard sphere and high internal phase emulsion templating gives a platform for synthesizing hierarchically porous polymers with a unique topology exhibiting interconnected spherical features on multiple levels. Polymeric spheres are fused by thermal sintering to create a 3D monolithic structure while an emulsion with a high proportio...

The herald moths, Scoliopteryx libatrix, overwinter in hypogean habitats. The ultrastructure of their fat body (FB) cells and Malpighian tubule (MT) epithelial cells was studied by light microscopy and transmission electron microscopy, and essential biometric and biochemical measurements were performed. The FB was composed of adipocytes and sparse...

During winter, cave cricket larvae undergo dormancy in subterranean habitats; this dormancy is termed diapause in second year Troglophilus cavicola larvae because they mature during this time, and termed quiescence in T. neglectus, because they mature after dormancy. Here we used electron microscopy to analyze ultrastructural changes in the epithel...

Two phalangiid species, Amilenus aurantiacus (Simon, 1881) and Gyas annulatus (Olivier, 1791) (Opiliones, Phalangiidae), spend their winter dormancy in large numbers in subterranean habitats. In caves they rest on the walls and ceilings of the entrance sections. Both are considered trogloxenes, or the latter are sometimes classified as troglophiles...

The cave cricket Troglophilus neglectus regularly overwinters for 4-5 months in hypogean habitats. Winter dormancy is a natural starvation period, providing the opportunity to study autophagy under natural conditions. We aimed to evaluate the autophagic activity in adipocytes and urocytes of the fat body in three time frames: directly before overwi...

Izvleček UDK 595.142:551.442(497.4Huda luknja) Tone Novak, Csaba Csuzdi, Franc Janžekovič, Tanja Pipan, Dušan Devetak & Saša Lipovšek: Preživetje površinskega deževnika Dendrodrilus rubidus tenuis (Oligochaeta: Lum-bricidae) v podzemeljskem okolju V vzorcih curka prenikajoče vode v Hudi luknji pri Doliču je bila peregrina vrsta deževnika dendrodril...

The peregrine earthworm Dendrodrilus rubidus tenuis was regularly sampled in a percolating water drip originating in a habitat inaccessible to humans in the Huda luknja pri Dolicu cave, Slovenia. The reconstruction of this habitat includes both a larger passage with bat colonies supplying wet bat guano sediments, on which the earthworms feed, and n...

The harvestmen Amilenus aurantiacus overwinter in diapause in hypogean habitats. The midgut diverticula have been studied microscopically (light microscopy, TEM) and biochemically (energy-storing compounds: lipids and glycogen) to analyze changes during this programmed starvation period. Throughout the investigated period, the epithelium of the mid...

Apoptosis, autophagy and necrosis are three distinct functional types of the mammalian cell death network. All of them are characterized by a number of cell’s morphological changes. The inappropriate induction of cell death is involved in the pathogenesis of a number of diseases. Pathogenesis of inflammatory bowel diseases (ulcerative colitis, Cro...

Most organisms are able to survive shorter or longer exposure to sub-zero temperatures. Hypothetically, trogloxenes characterized as not adapted, and troglophiles as not completely adapted to thermally stable subterranean environment, have retained or partially retained their ability to withstand freezing, while most troglobionts have not. We teste...

Juvenile harvestmen Gyas annulatus overwinter in dormancy in hypogean habitats for 4-5 months. The ultrastructure of the autophagic structures in their midgut epithelium cells was studied by light-, transmission electron microscopy (TEM) and immunofluorescence microscopy (IFM) during this non-feeding period. Before overwintering (November), autopha...

Eleven of the most important terrestrial invertebrate species in Slovenian caves were analyzed for differences in their fresh and dry biomass, energy content and carbon bulk during winter. These data were combined with the species abundance in 54 caves and adits in order to estimate their organic carbon bulk and carbon input into these habitats. In...

Morphology and behaviour of third instar larvae of the Holomediterranean antlion species Myrmecaelurus trigrammus (Pallas) are described. Larvae are facultative pit-builders, they either ambush their prey at the surface, or dig pitfall traps that prey fall in to. Dark brown spots on dorsal and ventral sides of the head and on dorsal side of the tho...

In this work we have compared the ultrastructural characteristics of major pancreatic endocrine cells, pituitary melanotrophs and adrenal chromaffin cells in the normal mouse strain (wild type, WT) and mice with a known secretory deficit, the Rab3a knockout strain (Rab3a KO). For this purpose, pancreata, pituitary glands and adrenal glands from the...

Terrestrial animals in subterranean habitats are often classified according to their degree of morphological or ecological specialization to the subterranean environment. The commonly held view is that, as distance into a cave increases, the frequency of morphologically specialized, i.e., troglomorphic, species or ecological specialization will inc...

This study presents an application of analytical electron microscopy in biology to investigate the chemical composition of the spherites and to elucidate the importance of these methods in the life sciences. The structure of the spherites in the midgut cells of first, second, and third instar larvae Euroleon nostras was investigated by a combinatio...

We analysed structural differences between midgut epithelial cells of fed instar antlions' larvae Euroleon nostras and starved ones. In starved larvae the presence of autophagolysosome-like structures was observed, which are characteristic structures associated with autophagy. The results presented here provide insight supporting the role of autoph...

Freshly isolated pancreatic islets contain, in contrast to cultured islets, intraislet endothelial cells (ECs), which can contribute to the formation of functional blood vessels after transplantation. We have characterized how donor islet endothelial cells (DIECs) may contribute to the revascularization rate, vascular density, and endocrine graft f...

The cave crickets Troglophilus cavicola and Troglophilus neglectus are the most widely distributed European species of the family Rhaphidophoridae. Their life cycles span two years. They overwinter twice in caves in 4-6 months lasting diapause, T. cavicola in warmer microhabitats. In caves, older T. cavicola undergo sexual maturation, while T. negl...

Hypogean habitats are relatively simple exhibiting low diversity, low production and relative constancy of environmental factors, and are therefore appropriate for studying species coexistence in situ. We investigated the coexistence of two closely related, similarly sized orb-weaving spider species, Meta menardi and Metellina merianae, living synt...

The antlion Myrmeleon yemenicus is known from SW of the Arabian Peninsula where it inhabits shrubland and rock communities at the altitudes higher than 1800 metres above sea level. Morphology and behaviour of larvae and adults are described. Larvae construct conical pits in loose soil and wait for prey at the bottom of the trap. Catching behaviour...

Article Larval morphology of the antlion Neuroleon microstenus (McLachlan, 1898) (Neuroptera, Myrmeleontidae), with notes on larval biology Abstract Larval stages of the Mediterranean antlion species Neuroleon microstenus (McLachlan) are described and illustrated. Larvae do not build pitfall traps. They pursue prey by digging in sand backwards and...

Larval stages of the Mediterranean antlion species Neuroleon microstenus (McLachlan) are described and illustrated. Larvae do not build pitfall traps. They pursue prey by digging in sand backwards and waiting a prey. Second and third instar larvae move backwards or forwards on sand surface, whilst first instar larvae only forwards. Characteristic f...

Proceedings of the Tenth International Symposium on Neuropterology, Piran, Slovenia, 22-25 June 2008. Edited by Dušan Devetak, Saška Lipovšek & Amy E. Arnett. The Proceedings include contributions of the following authors: Aspöck, H., Aspöck, U., Badano, D., Belušič, G., Blaik, T., Bozsik, A., Canard, M., Cesaroni, C., Contreras-Ramos, A., Devetak...

Periodical changes in the structure of spherites in the Malpighian tubule cells of the cave cricket Troglophilus neglectus were studied to elucidate their role during the cricket's life cycle in natural circumstances. Special interest was given to the dormant overwintering period when we hypothesized that the primary role of spherites is to supply...

The aim of this study was to define when an insulin-positive cell becomes functional in vivo and starts to exocytose insulin in a regulated nutrient-dependent manner. Insulin-positive cells appear in embryonic life (midgestation) and complete their maturation, presumably around birth. In order to work with embryonic and newborn endocrine pancreas,...

The aim of this study was to define when an insulin-positive cell becomes functional in vivo and starts to exocytose insulin in a regulated nutrient-dependent manner. Insulin-positive cells appear in embryonic life (midgestation) and complete their maturation, presumably around birth. In order to work with embryonic and newborn endocrine pancreas,...

Phalangium opilio is the most widespread and one of the most common harvestman species in anthropogenic environments. A preliminary field experiment was carried out in Slovenia testing its preferences for different substrates. A two metres high rectangular tower with walls constituted of vertical bands of concrete, twice fired tile, wood and styrof...

In this case study we present an application of different analytical electron microscopic methods in biology, to elucidate their usefulness in such investigations. Using analytical electron microscopy, spherites in the digestive gland cells of the helicid snail Chilostoma lefeburiana were examined at three stages: just before the non-feeding period...

The authors present a short historical faunistic, zoogeographical and ecological review of research on harvestmen (Opiliones) of the territory of presentday Slovenia, and discuss some actual ecological and nature conservational questions. Till recent, 64 species plus two subspecies of Opiliones inhabiting Slovenia are recorded, most of these are Al...

The structure of the midgut gland and its changes in different seasons have been examined in the harvestmen Gyas annulatus and Gyas titanus (Arachnida: Opiliones: Phalangiidae). In both species, in the epithelium of the midgut gland two different types of cells are present: secretory and digestive ones. The secretory cells are characterized by plen...

Gyas annulatus and G. titanus (Arachnida: Opiliones: Phalangiidae) were studied comparatively with special interest in their hypogean ecophase. Direct comparisons were made in two caves where both species overwintered, and in the laboratory. Their chilling hardiness was tested, and the dynamics of lipid and glycogen stocks was studied. Juveniles ov...

The femoral chordotonal organ (FCO) and the subgenual organ (SGO) of the green lacewing Chrysoperla carnea were examined by conventional light and confocal laser scanning microscopy in order to search for neuroactive substances which are used for neurotransmission in sensory cells of these organs. Antibodies against serotonin, histamine and choline...

Spherites--round laminated membrane bound structures--are located in the cytoplasm of all cell types of the midgut gland in the harvestmen Gyas annulatus. The spherites consist of an organic matrix composed of glycoproteins and proteoglycans whose sugar portion are carboxylated glycosaminoglycans. Different elements are embedded in this matrix, and...

The abundance of species of Neuroptera was studied in the traditional cultural landscape of Goričko (NE Slovenia). The insects were collected during 1997, 1998 and 1999 at 12 different localities. The green lacewing Chrysoperla carnea sensu lato was the most dominant species in the region. This species was the only one found in cultivated fields in...

On the basis of 33 locality records of Gyas titanus Simon, 1879 (Opiliones, Phalangiidae) it is stated that the species more or less continuously inhabits the western and middle Balkans. Thus the Alpine-Balkans-Carpathian range of the species is continuous.

On the basis of 33 locality records of Gyas titanus Simon, 1879 (Opiliones, Phalangiidae) it is stated that the species more or less continuously inhabits the western and middle Balkans. Thus the Alpine-Balkans-Carpathian range of the species is continuous.

The femoral chordotonal organ (FCO) inChrysoperla carneais situated in the distal part of the femur and consists of two scoloparia, which are fused at their distal end. The distal scoloparium contains 17-20 scolopidia, and the proximal one six scolopidia. Each scolopidium consists of two sensory cells and three types of enveloping cells (glial, sco...

The ultrastructural colony architecture of four Clostridium difficile strains belonging to four different ribotypes (001, 027, 078/126 and 036) was studied using scanning electron microscopy (SEM). Clostridium difficile is a sporogenic, anaerobic, Gram positive rod, and is currently one of the most important hospital and health care associated path...

This comparative study provides information on the physiological relevance of spherites in three species of various higher taxa during overwintering: the helicid snail Chilostoma lefeburiana, the harvestman Gyas annulatus and the cave cricket Troglophilus neglectus. They all spend a 4−6 months inactive winter ecophase in caves and other hypogean ha...