Influence of soil contaminated with cadmium on cell death in the digestive epithelium of soil centipede Lithobius forficatus (Myriapoda, Chilopoda)

Cadmium is a heavy metal that is treated as an environmental pollutant (air, water, soil). In order to understand the potential effects of cadmium in soil and soil invertebrates, it is important to describe all alterations which appear at different levels in organisms. The main aim of this study was to investigate, analyze and describe the alterations caused by cadmium short- and long-term intoxication at different levels in the organisms: from tissues to cells and organelles. In addition, the activation of cell deathmechanisms that take part in homeostasismaintenance according to cadmium has been studied. Therefore, as the species for this project, a terrestrial and well-known widespread European species – the centipede Lithobius forficatus (Myriapoda, Chilopoda, Lithobiomorpha) – was chosen. This omnivorous species lives under upper layers of soil, under stones, litter, rocks, and leaves, and it is also commonly found in human habitats. The animals were divided into three groups: C – the control group, animals cultured in a horticultural soil; Cd1 – animals cultured in a horticultural soil supplemented with 80 mg/kg (dry weight) of CdCl2, 12 days – short-term exposure; Cd2 – animals cultured in a horticultural soil supplemented with 80 mg/kg (dry weight) of CdCl2, 45 days – long-term exposure. The midgut was isolated from each specimen and it was prepared for analysis using some histological, histochemical and immunohistochemical methods. Our studies showed that short-term intoxication causes intensification of autophagy and digestion of reserve material, while long-term exposure to this heavy metal causes activation of cell death processes together with inhibition of autophagy connected with the lack of reserve material. Additionally, we can infer that autophagy and cell death are nutrient deprivation-induced processes. Finally, we can conclude that short- and long-term exposure of soil centipede to cadmium affects different mechanisms and processes of cell death

The activity of hydrolytic enzymes in the digestive system of Acanthobdellida, Branchiobdellida and Hirudinida (Annelida,Clitellata) – considerations on similarity and phylogeny

Activities of nineteen hydrolases were measured in the digestive systems of predatory and blood-feeding true leeches (Hirudinida) and their closest relatives, Branchiobdellida and Acanthobdellida. Hydrolase activities were analyzed in different parts of the digestive systems: the species-specific anterior part, i.e. jaws, pharynx or proboscis, crop and intestine. The results obtained suggest that food digestion and possible absorption predominate in the intestine of most of the studied Hirudinida and A. peledina, whereas in B. astaci these processes take place in the anterior part of the digestive system and crop. In Erpobdellidae and Piscicola respirans, the activity of acid and alkaline phosphatases, N-acetyl-β-glucosaminidase, leucine and valine arylamidases, and α-fucosidase was also detected in the anterior part of the digestive system. We also detected differences in enzyme occurrence between the studied species, which are probably connected with their different food preferences. Moreover, the presence of the whole spectrum of enzymes in predatory leeches and the absence of trypsin and α-chymotrypsin activity in the crop of all the leeches support the hypothesis that the leech ancestor was a blood-feeder. Our study showed that “Rhynchobdellida” constitute a paraphyletic group which confirms the previous results based on molecular phylogenetics, while Arhynchobdellida appears to be a non-monophyletic group which is not consistent with previous molecular results

Figure 4 in Body cavity cells of Parachela during their active life

Figure 4. Histochemical staining of Hypsibius dujardini, Macrobiotus polonicus, Xerobiotus pseudohufelandi, and Isohypsibius granulifer granulifer; arrows indicate a positive reaction. A–C, histochemical staining of the storage cells of I. g. granulifer. LM. A, Periodic Acid-Schiff (PAS) method, scale bar = 7 µm. B, Sudan black B staining, scale bar = 5 µm. C, bromophenol blue staining (BPB), scale bar = 6 µm. D–F, histochemical staining of the storage cells of H. dujardini. LM. D, PAS method, scale bar = 6 µm; E, Sudan black B staining, scale bar = 6 µm; F, BPB, scale bar = 6 µm. G–I, histochemical staining of the storage cells of M. polonicus. LM. G, PAS method, scale bar = 9 µm; H, Sudan black B staining, scale bar = 7 µm; I, BPB, scale bar = 8 µm. J–L, histochemical staining of the storage cells of X. pseudohufelandi. LM. J, PAS method, scale bar = 11 µm; K, Sudan black B staining, scale bar = 11 µm; L, BPB, scale bar = 11 µm. LM, light microscope.Published as part of <i>Hyra, Marta, Rost-Roszkowska, Magdalena M., Student, Sebastian, Włodarczyk, Agnieszka, Deperas, Marcin, Janelt, Kamil & Poprawa, Izabela, 2016, Body cavity cells of Parachela during their active life, pp. 878-887 in Zoological Journal of the Linnean Society 178 (4)</i> on page 885, DOI: 10.1111/zoj.12463, <a href="http://zenodo.org/record/10110454">http://zenodo.org/record/10110454</a&gt