The role of autophagy in the midgut epithelium of Parachela (Tardigrada)

Abstract

The process of cell death has been detected in the midgut epithelium of four tardigrade species which belong to Parachela: Macrobiotus diversus, Macrobiotus polonicus, Hypsibius dujardini and Xerobiotus pseudohufelandi. They originated from different environments so they have been affected by different stressors: M. polonicus was extracted from a moss sample collected from a railway embankment; M. diversus was extracted from a moss sample collected from a petrol station; X. pseudohufelandi originated from sandy and dry soil samples collected from a pine forest; H. dujardini was obtained commercially but it lives in a freshwater or even in wet terrestrial environment. Autophagy is caused in the digestive cells of the midgut epithelium by different factors. However, a distinct crosstalk between autophagy and necrosis in tardigrades’ digestive system has been described at the ultrastructural level. Apoptosis has not been detected in the midgut epithelium of analyzed species. We also determined that necrosis is the major process that is responsible for the degeneration of the midgut epithelium of tardigrades, and “apoptosis–necrosis continuum” which is the relationship between these two processes, is disrupted.

Relationship between ROS production, MnSOD activation and periods of fasting and re-feeding in freshwater shrimpNeocaridina davidi(Crustacea, Malacostraca)

“…In recent years, intensive studies connected with the response of organisms to the stress of starvation/fasting in invertebrates have been carried out. In the studied invertebrate species, the authors described the susceptibility to starving and changes at the ultrastructural level in the epithelium of the digestive system (Wilczek et al, 2014; Lipovšek et al., 2015; Lipovšek et al, 2018; Lipovšek & Novak, 2015; Rost-Roszkowska, Janelt & Poprawa, 2018), including crustaceans (Cervellione, McGurk & Van Den Broeck, 2017; Pantaleão et al, 2015; Sacristán, Nolasco-Soria & López Greco, 2014; Sacristán et al, 2016; Włodarczyk et al, 2017; Włodarczyk, Student & Rost-Roszkowska, 2019). Ultrastructural changes may be associated with an increase in the concentration of free radicals in the examined cells (Kaminskyy & Zhivotovsky, 2014; Chen, Azad & Gibson, 2009; Redza-Dutordoir & Averill-Bates, 2016).…”

In Vivo Autophagy Up-Regulation of Small Intestine Enterocytes in Chinese Soft-Shelled Turtles during Hibernation

“…During long periods of starvation, too many autophagosomes developed. Eventually, the cytoplasm of the cell is filled with autophagosomes, and then the cell membrane ruptures, and organelles are discharged into the lumen of the intestine [11]. During the period of hibernation, more reserve bodies are gathered in the cytoplasm of enterocytes, which might be eventually removed through autophagy because this process performs a role in cell death [58].…”

“…However, animal bodies have developed different physiological defense mechanisms against any stressor that could enter into the animals along with nutrients in the digestive system [10]. One of the defense mechanisms is autophagy, which participates in the promotion of cellular fitness and the maintenance of intestinal homeostasis [11].…”

Peer Review #1 of "Relationship between ROS production, MnSOD activation and periods of fasting and re-feeding in freshwater shrimp Neocaridina davidi (Crustacea, Malacostraca) (v0.1)"

“…In recent years, intensive studies connected with the response of organisms to the stress of starvation/fasting in invertebrates have been carried out. In the studied invertebrate species, the authors described the susceptibility to starving and changes at the ultrastructural level in the epithelium of the digestive system (Wilczek et al, 2014;Lipovšek et al, , 2018Rost-Roszkowska et al, 2018), including crustaceans (Cervellione et al, 2017;Pantãleo et al, 2015;Sacristán et al, 2014Sacristán et al, , 2016Włodarczyk, 2017Włodarczyk, , 2019. Ultrastructural changes may be associated with an increase in the concentration of free radicals in the examined cells (Kaminskyy and Zhivotovsky, 2014;Chen et al, 2009;Redza-Dutordoir et al, 2016).…”