Ultrastructural, histochemical and cytochemical characterization of intestinal epithelial cells in <i>Aplysia depilans</i> (Gastropoda, Opisthobranchia)

Bessette

et al. 2010

Journal of Morphology

To understand the digestive functions in the giant keyhole limpet, it is important to know the types of cells present in each region of the gut and their roles in the secretion of digestive enzymes and absorption of nutrients. This study describes the morphology of cells lining the entire gut and identifies sites that may be secreting materials to aid digestion. Previous studies involving electron microscopy and enzyme analysis have focused on the salivary and digestive glands of several gastropods. Studies on the rest of the gut tract typically include only histological descriptions of the epithelia and although several types of cells have been described, they appear very similar. The purpose of this study is to determine if electron microscopy can provide better insights into the functions of cells in these poorly studied regions of the gut. Our ultrastructural observations suggest that only two types of cells, mucus secreting cells and apocrine secretory cells make up the epithelium in the esophagus, style sac, and intestine. These regions account for 85% of the length of the entire digestive tract. Apocrine secretory cells contain pigment granules, bear cilia, and/or microvilli at their apices, and release product into the gut lumen via apocrine secretion. This suggests that the secretory processes involved with digestion are occurring in most regions of the gut and that apocrine secretion is the primary mode by which materials are introduced into the gut lumen. The lips, salivary glands, stomach, and digestive gland lack apocrine secretory cells and the epithelial cells are similar to those described in other gastropods. J. Morphol. 271:1134-1151, 2010. (c) 2010 Wiley-Liss, Inc.

Section: Introductionmentioning

confidence: 99%

Morphology of epithelial cells lining the digestive tract of the giant keyhole limpet, Megathura crenulata (Mollusca; Vetigastropoda)

Bessette

et al. 2010

Journal of Morphology

“…external morphology and radula (Bebbington & Thompson, 1968; Bebbington, 1970; Thompson, 1976); shell (Rang, 1828; Pruvot-Fol, 1933; Grigg, 1949; Bebbington, 1970, 1975; Cossignani et al ., 1992); opaline gland (Pilsbry, 1895; Pruvot-Fol, 1954); hermaphrodite reproductive system (Mazzarelli, 1891; Thompson & Bebbington, 1969); and nervous system (Mazzarelli, 1893; Wirz, 1952; Kandel & Tauc, 1965). On the other hand, the digestive system of A. depilans has been investigated in relative detail, with several articles addressing its histochemical and ultrastructural properties (Lobo-da-Cunha, 1999, 2000, 2001, 2002; Lobo-da-Cunha & Batista-Pinto, 2003, 2005, 2007).…”

Section: Introductionmentioning

confidence: 99%

Morphological re-description ofAplysia depilans(Gastropoda: Anaspidea): new insights into the anatomy of the anaspideans

Cunha

Simone

2018

J. Mar. Biol. Ass.

Although Aplysia depilans is a widely known European species and the type species of the genus, the distinctions that separate it from other related congeners are not entirely clear. Aimed at improving this scenario, a detailed morphological description is performed herein, showing some unprecedented and useful features. Based on our anatomical examination, this study has found the opaline gland to be dark in colour, as well as a metapodium with an indistinctly delimited pedal sucker, a crop divided into two equal chambers of similar volume by a circular muscle, gizzard plates arranged in groups, and a peculiar penial sheath structure. All of these characters appear to be significantly different from the other species, based on a review of the anatomical literature and several examined samples of ongoing studies. Our central objective is to provide new data on the anatomy of the type species of Aplysiidae; and, based on topological evidence, to propose a new terminology and possible homologies to some important characters, such as parapodia lobation, cephalic tentacles, crop, penial sheath, gizzard plates and visceral ganglion in anaspideans, for future phylogenetic analysis. The subgenus Subaplysia Medina, Collins & Walsh, 2005 is regarded as a junior synonym of subgenus Aplysia Linnaeus, 1767.

“…In these marine organisms, most of the digestion and nutrient absorption occurs in the digestive gland; the waste coming from it returns to the stomach, being conducted into the incurrent channel of the caecum. Subsequently, the undigested substances are carried by ciliary currents and muscular activity, being transferred to the excurrent channel of the caecum, where the fecal rods are formed [4,5].…”

Section: Introductionmentioning

confidence: 99%

Digestive Gland from Aplysia depilans Gmelin: Leads for Inflammation Treatment

et al. 2015

Self Cite

Abstract:The exploitation of marine organisms for human nutritional and pharmaceutical purposes has revealed important chemical prototypes for the discovery of new drugs, stimulating compounds isolation and syntheses of new related compounds with biomedical application. Nowadays, it is well known that inflammatory processes are involved in many diseases and the interest in the search for marine natural products with anti-inflammatory potential has been increasing. The genus Aplysia belongs to the class Gastropoda, having a wide geographical distribution and including several species, commonly known as sea hares. Aplysia depilans Gmelin is usually found in the Mediterranean Sea and in the Atlantic Ocean, from West Africa to the French coast. In these marine organisms, most of the digestion and nutrient absorption occurs in the digestive gland. This work aimed to explore the chemical composition and bioactivity of the methanol extract from A. depilans digestive gland. Therefore, fatty acids and carotenoids were determined by GC-MS and HPLC-DAD, respectively. Twenty-two fatty acids and eight carotenoids were identified OPEN ACCESSMolecules 2015, 20 15767 for the first time in this species. The A. depilans digestive gland revealed to be essentially composed by polyunsaturated fatty acids (PUFA) and xanthophylls. Regarding the anti-inflammatory potential in RAW 264.7 cells stimulated with lipopolysaccharide, it was observed that this matrix has capacity to reduce nitric oxide (NO) and L-citrulline levels, which suggests that its compounds may act by interference with inducible nitric oxide synthase. Taking into account the results obtained, A. depilans digestive gland may be a good source of nutraceuticals, due to their richness in health beneficial nutrients, such as carotenoids and long-chain PUFA.