Apoptosis and necrosis during the circadian cycle in the centipede midgut

Abstract

Three types of cells have been distinguished in the midgut epithelium of two centipedes, Lithobius forficatus and Scolopendra cingulata: digestive, secretory, and regenerative cells. According to the results of our previous studies, we decided to analyze the relationship between apoptosis and necrosis in their midgut epithelium and circadian rhythms. Ultrastructural analysis showed that these processes proceed in a continuous manner that is independent of the circadian rhythm in L. forficatus, while in S. cingulata necrosis is activated at midnight. Additionally, the description of apoptosis and necrosis showed no differences between males and females of both species analyzed. At the beginning of apoptosis, the cell cytoplasm becomes electron-dense, apparently in response to shrinkage of the cell. Organelles such as the mitochondria, cisterns of endoplasmic reticulum transform and degenerate. Nuclei gradually assume lobular shapes before the apoptotic cell is discharged into the midgut lumen. During necrosis, however, the cytoplasm of the cell becomes electron-lucent, and the number of organelles decreases. While the digestive cells of about 10 % of L. forficatus contain rickettsia-like pathogens, the corresponding cells in S. cingulata are free of rickettsia. As a result, we can state that apoptosis in L. forficatus is presumably responsible for protecting the organism against infections, while in S. cingulata apoptosis is not associated with the elimination of pathogens. Necrosis is attributed to mechanical damage, and the activation of this process coincides with proliferation of the midgut regenerative cells at midnight in S. cingulata.

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

“…Therefore, only cells that reach the midgut lumen can be affected by a stressor (Wilczek et al 2014; Włodarczyk et al 2017). In all of the tardigrades examined here, autophagy and necrosis were only detected in the digestive cells of the midgut epithelium, while they were not observed in the cytoplasm of the regenerative cells as has been described for other invertebrates (Tettamanti et al 2007; Rost-Roszkowska et al 2015, 2016). Apoptosis was not observed in the midgut epithelium of any of the species examined here.…”

“…However, three types are best known: apoptosis, necrosis and autophagy. They are common processes that occur in the digestive epithelia of invertebrates (Malagoli et al 2010 ; Franzetti et al 2012 ; Romanelli et al 2014 , 2016 ; Wilczek et al 2014 ; Lipovšek and Novak 2015 ; Rost-Roszkowska et al 2015 , 2016 ; Sonakowska et al 2016 ). When the cytoplasm is rich in autophagic structures, apoptosis and/or necrosis is activated (Levine and Yuan 2005 ; Giusti et al 2007 ; Tettamanti et al 2007 ; Rost-Roszkowska et al 2013b ).…”

Postembryonic development and differentiation of the midgut in the freshwater shrimp Neocaridina davidi (Crustacea, Malacostraca, Decapoda) larvae

“…Depending on the strength of the stressor, autophagy may allow a cell to survive or trigger apoptosis/necrosis (Klionsky & Emr, 2000;Kourtis & Tavernarakis, 2009). However, when there are too many autophagic structures in the epithelial cell, necrosis as passive cell death is activated (Lipovšek et al, 2018;Rost-Roszkowska et al, 2016, 2019. Autophagy is eventually treated as a survival factor in degradation of the crustacean midgut epithelium, which is devoid of regenerative cells, for example, the shrimp Eubranchipus grubii (Rost-Roszkowska et al, 2012) and also in N. davidi adult specimens after different periods of starvation (Włodarczyk et al, 2019a).…”

“…Three main types of cell death have been recognized in the digestive system of invertebrates: apoptosis, necrosis, and autophagy. Cell death maintains homeostasis in the event of external stressors, and can be involved in embryonic and postembryonic development of tissues and organs (Bruno et al, 2019; Caccia, Casartelli, & Tettamanti, 2019; Franzetti et al, 2012, 2016; Klionsky & Emr, 2000; Kourtis & Tavernarakis, 2009; Lipovšek et al, 2018; Lipovšek, Janžekovič, & Novak, 2014; Lipovšek & Novak, 2016; Rost‐Roszkowska et al, 2010, 2019; Rost‐Roszkowska, Chajec, Vilimova, & Tajovsky, 2016; Rost‐Roszkowska, Janelt, & Poprawa, 2018; Sonakowska et al, 2016; Tettamanti, Cao, Feng, Grimaldi, & de Eguileor, 2011; Tettamanti, de Busserolles, Lecchini, Marshall, & Cortesi, 2019; Wilczek et al, 2014; Włodarczyk et al, 2019a).…”

Autophagy and Apoptosis in the Midgut Epithelium of Millipedes

“…Autophagy and apoptosis have been described as commonly occurring in the midgut epithelium of centipedes (Myriapoda, Chilopoda) (Rost-Roszkowska et al, 2015, 2016), where they have been described in digestive, secretory, and regenerative cells. Among millipedes (Myriapoda, Diplopoda), the autophagy has been described in the cytoplasm of hepatic cells (De Godoy & Fontanetti, 2010; Nogarol & Fontanetti, 2011; Rost-Roszkowska et al, 2018 a ) or fat body cells (Fontanetti et al, 2006).…”