Therapeutic effect of lauric acid, a medium chain saturated fatty acid on giardia lamblia in experimentally infected hamsters

Giardia lamblia is a common cause of diarrheal disease in humans, particularly among children causing nutritional disorders. Metronidazole and other nitroimidazoles are commonly used as the mainstay of therapy for giardiasis. The present work was carried out to evaluate the effect of lauric acid, a natural product extracted from coconut oil, against G. lamblia in experimentally infected hamsters [Mesocricetus auratus]. Sixty five laboratory bred hamsters were used in the current experimental study. Ten served as normal non infected non treated control group [A]. Fifteen uninfected hamsters served as drug control group [B]: five received metronidazole group [B1]; five received lauric acid group [B2] and five received combined treatment [metronidazole and lauric acid] at a half doses of each drug [B3]. The remaining forty hamsters were orally infected by 10,000 G. lamblia cysts/hamster [group C], and were divided into 4 groups of 10 hamsters each: infected control [C1]; metronidazole treated [C2]; lauric acid treated [C3]; combined treatment at a half dose of each drug [C4]. Two weeks after treatment, compared with infected non treated controls, the highest percentages of reduction in the number of Giardia cysts and trophozoites were in the group that received combined treatment [98.83%, 96.95%, respectively]. Lower percentages of reduction were recorded for the metronidazole treated group [93.77%, 95.50%, respectively] and the lauric acid treated group [82.03%, 78.76%, respectively]. Histopathological examination and electron microscopic examination revealed complete healing of intestinal mucosa after the combined treatment, while partial healing of the lining epithelium of the intestine was noticed after metronidazole or lauric acid treatment alone. Lauric acid improved the therapeutic effect against giardiasis when combined with metronidazole

Ultrastructural intestinal pathology induced by human Blasocystis in experimentally infected mice

Blastocystis spp. is a single-celled anaerobic enteric parasite that inhabits the lower gastrointestinal tract of humans and many animals. This emerging parasite with a worldwide distribution is often identified as the most common eukaryotic organism reported in human fecal samples that showed a dramatic increase in recent years; however its pathogenicity still shows many contradictions. To evaluate the histological and ultrastructural pathological changes induced by human Blastocystis isolates in the intestine of experimental infected mice. Fecal samples positive for Blastocystis were collected from patients, and processed for culture using Jones' medium. Cultured samples were subjected to examination by light and transmission electron microscopy. Blastocystis cyst stages were isolated and orally fed to immunocompetent BALB/c mice. Mice were sacrificed 2 weeks post infection. Semi-thin and ultra-thin sections prepared from their intestine were examined by both light and transmission electron microscopy [TEM], respectively. Blastocystis showed different forms: vacuolar, granular, amoeboid and cysts within 24 hours in culture. Histological examination of infected intestine showed vacuolar, granular and amoeboid forms in the caecum, but only cyst forms were observed in the colon. Intense inflammatory cell infiltration, edematous lamina propria, and villous atrophy were noticed. Ultrastructure of Blastocystis hominis by TEM revealed the surface coat with outer fibrillar layer, nuclei with multiple chromatin masses, and mitochondria with some pathological tubular changes. Atrophy and sloughing of microvilli of infected intestine was noticed in comparison to the mucosa of control non-infected mice that showed normal brush border and microvilli. Infection with Blastocystis may be self limited in some hosts however it may cause considerable pathological changes such as enterocytes invasion and intestinal mucosal atrophy of infected mice. Blastocystis mitochondrial vacuolations were detected within intestine of infected mice compared to culture forms. Thus, apparently B. hominis is capable of causing pathogenicity

effects of comparison of herbal extracts, antibiotic, probiotic and organic acid on serum lipids, immune response, GIT microbial population, intestinal morphology and performance of broilers

With the removal of antibiotic as growth promoters from poultry diets, it is of interest to investigate potential alternatives to maintain good growth performance and good intestinal microbial populations in these birds. Numerous additives such as Probiotics, prebiotics, organic acids, enzymes and herbal extracts used extensively in poultry feed. The study was conducted to investigate the effects of herbal extracts, probiotic, organic acid and antibiotic on serum lipids, immune response, intestinal morphology, microbial population and performance of broilers. A total of 300 day - old male broilers [Cobb 500] were randomly divided into four treatments, five replicates with 15 birds in each. Treatments included: control, herbal extracts [Sangrovit [R]], probiotic [Primalac[R]], organic acid [Termin-8[R]] and antibiotic [Virginiamycin]. The highest weight gain [WG] were achieved by virginiamycin [p<0.05]. Moreover, highest and lowest antibody titers against SRBC were observed in Primalac_ and virginiamycin treatments, respectively [p<0.05]. Lowest serum cholesterol and triglyceride were obtained by Primalac[R] and Sangrovit_ [p<0.05]. The lowest and highest coliform bacteria counts in ileum were seen in virginiamycin and control groups, respectively [p<0.05]. It has been concluded that Sangrovit[R], Primalac[R] and Termin-8[R] reduced pathogenic bacteria in digestive tract of broilers, which can help to improve intestinal health of these animals. Thus, these can be used as antibiotic alternatives in broilers feed

Intestinal lesions of streptozotocin diabetes and the effects of azadirachta indica treatment

To determine the effects of chronic streptozotocin diabetes on the morphology of ileal epithelium and to find out the effects of chronic Azadirachta indica treatment on STZ-induced ileal lesions. Twenty-five Wistar rats of both sexes [5-8 weeks old] were used. Diabetes was induced in 15 rats with an i.p. dose of 70 mg/kg bw/d of STZ in citrate buffer [0.1 M; pH 4.5]. Animals were randomly sorted into five groups of five rats each: control, diabetic, diabetic+neem, diabetic+ glibenclamide, neem only. Azadirachta indica was administered at 500 mg/kg bw/d for 50d, diabetic rats showed superficial erosion of ileal mucosa with necrosis of goblet cells. Such lesions were however absent in hyperglycemic and normoglycemic rats treated with neem. These findings suggest that [i] chronic streptozotocin diabetes is associated with intestinal lesion; [ii] neem prevents STZ-induced intestinal lesions; and [iii] exposure of intestinal mucosa to the leaf extract of Azadirachta indica in non-diabetic rats is not associated with deleterious effects

Comparative intestinal histomorphology of five species of Phyllostomid bats (Phyllostomidae, Microchiroptera): ecomorphological relations with alimentary habits / Histomorfometría comparativa de intestino de cinco especies de murciélagos Phyllostomideos (Phyllostomidae, Microchiroptera): relaciones ecomorfológicas con hábitos alimentarios

The intestines of Sturnira lilium, Phyllostomus hastatus, Carolliaperspicillata, Glossophagasoricinaíind Desmodus rotundus were analized through macroscopic, morphometric and light microscopy studies. The species studied presented some common charactenstics generally found in bats, such as the absence of a caecum and an appendix. The frugivorous bat S. lilium has a longer intestine than the other species. The intestinal epithelium is of the simple columnar type, constituted of absorptive cells characterized by microvilli and goblet cells, which in all the species proved to be PAS + and AB +. These cells presented some differences in quantity and in distribution among the species. The intestinal mucosa presented morphologic and morphometric differences, such as the shape and size of villi as well as the length of the crypts of Lieberkühn. Histologically the different intestinal portions could be distinguished: in the middle portion we found few goblet cells and long villi; in the distal portion we found an increase in goblet cells and a decrease in villi height; and in the large intestine no villi were found, but rather abundant intestinal glands with numerous goblet cells. In C. perspicillata, P. hastatus and G. soricina we could observe Peyeras patches in the distal portion near the large intestine, whereas in D. rotundus and S. lilium we found aggregations of lymphoid nodulous tissue distributed along the tube. In all species we observed the presence of Paneth cells at the base of the crypts of Lieberkühn. We could observe differences among the species in the distribution of collagen in the small intestine submucosa and serosa. The outer muscular layer has one circular layer and a longitudinal layer, the circular layer increasing in thickness along the tube. Large intestine charactenstics are uniform among the species. Sfractures such as the taenia coli and the appendices epiploicae were absent. These results should contribute not only...

Los intestinos de Sturnira azucenas, Phyllostomus hastatus, Carollia perspicillata, Glossophaga soricina y Desmodus rotundus se analizaron a través de estudios macroscópicos, morfométricos y de microscopía de luz. Las especies estudiadas presentan algunas características comunes en general encontradas en murciélagos, tales como la ausencia de un ciego y un apéndice. Murciélagos frugívoros S. azucenas tienen un intestino más largo que el de otras especies. El epitelio intestinal es de tipo columnar simple, constituido por células de absorción que se caracterizan por microveilosidades y células caliciformes, que en todas las especies resultó ser PAS + y AB +. Estas células presentan algunas diferencias en cantidad y en la distribución entre las especies. La mucosa intestinal presenta diferencias morfológicas y morfométricas, como la forma y el tamaño de las vellosidades, así como la longitud de las criptas de Lieberkühn. Histológicamente las diferentes partes intestinales pueden ser distinguidas: en la parte media encontramos pocas células caliciformes y largas vellosidades, en la porción distal encontramos un aumento de células caliciformes y una disminución en la altura de vellosidades, y en el intestino grueso no se encontraron vellosidades, sino más bien abundantes glándulas intestinales con numerosas células caliciformes. En C. perspicillata, P hastatus y G. soricina podemos observar placas de Peyer en la porción distal, cerca del intestino grueso, mientras que en D. rotundus y S. azucenas se encontraron agrupaciones de tejido linfoide nodular distribuido a lo largo del tubo. En todas las especies se observó la presencia de células Paneth en la base de las criptas de Lieberkühn. Hemos podido observar diferencias entre las especies en la distribución de colágeno en el intestino delgado y submucosa serosa. La capa muscular exterior tiene una capa circular y una capa longitudinal, la capa circular en el aumento de espesor a lo largo del...

Morphological aspect of the midgut of anopheles aquasalis (Curry, 1932) Insecta: Diptera / Aspecto morfológico del intestino medio de anopheles aquasalis (Curry, 1932) Insecta: Diptera

The midgut of adult female Anopheles aquasalis presents a narrow anterior or thoracic region and a distensible posterior or abdominal region constituted by the epithelium formed by a cell layer whose apical portion presents microvilli and the basal portion, a basal labyrinth. The thoracic region revealed heterogeneous cellular staining affinity mainly by the presence of acidic components. The ultrastructural aspect showed columnar cells with the presence of the vesicle, mitochondria, endoplasmic reticulum and secreting cells. The abdominal region of the midgut revealed an irregular epithelium whose cells presented a basophilic cytoplasm and acidophil granules. It was also found secreting and/or basal cells with narrow cytoplasm. The ultrastructural observation of this region demonstrated cells with evident nucleus, endoplasmic reticulum and mitochondria. Larger vesicles and small granules were found distributed throughout the cytoplasm. The basal lamina that supports the epithelium presented a generally irregular aspect and the muscle fibers have longitudinal and circular organization and were found separating the epithelium from the haemocel. This study will contribute to analyses on the vector mosquito-parasite interaction mechanism in this specimen.

La seccion media del intestino de la hembra de Anopheles aquasalis presenta una estrecha region anterior o toráxica y una region posterior o abdominal constituida por el epitelio formado por una camada de células cuya porcion apical presenta microvilosidades y la porcion basal presenta un laberinto basal. La region toráxica reveló afinidad de tintura celular principalmente para componentes acídicos. El aspecto ultra estructural mostró células columnares con la presencia de la vesícula, mitocondrias, retículo endoplasmático y células secretoras. La region abdominal del intestino medio reveló un epitelio irregular con células con citoplasma basófilo y granulos acidófilos. También se encontraron células secretoras y/o básales con citoplasma estrecho. La observacion ultra estructural de la region mostró células con núcleos, retículo endoplasmático y mitocondrias evidentes. Vesículas largas y granulos pequeños fueron encontrados distribuidos por todo el citoplasma. La lámina basal que apoya el epitelio presentó un aspecto irregular y las fibras musculares tienen organizacion longitudinal y circular y separan el epitelio del hemocele. Este estudio contribuirá al análisis del mecanismo de interaccion entre el mosquito y el parásito en este espécimen.

Effect of dietary arginine on the jejunal mucosa in indomethacin-induced intestinal injury: light and scanning electron microscopic study in male mice

The non-steroidal anti-inflammatory drug [NSAID] indomethacin causes, via its adverse effects, damage to the gastrointestinal mucosa of humans and experimental animals. The indomethacin-induced intestinal injury in mice jejunum is considered an experimental model of Crohn's disease, as one of the inflammatory bowel diseases [IBD's]. The semi-essential amino acid arginine, which is a precursor of nitric oxide, is proposed to promote gastrointestinal mucosal integrity. The present work aimed to study the possible protective role of dietary supplementation with arginine in ameliorating indomethacin-induced mucosal injury of mice jejunum. The present study was carried out on forty adult male mice which were divided into 4 equal groups; group I [negative control group] which received no treatment, group II [positive control]; mice received dietary L-arginine alone in a daily dose of 300 mg/Kg, group III [indomethacin group]; mice of this group received 2 consecutive subcutaneous injections of indomethacin in a dose of 7.5 mg/kg, 24 hours apart and group IV [arginine group]; in which arginine supplementation was provided 2 days before the administration of indomethacin, maintained during the administration and continued 3 days later till the end of the experiment. Mice of all groups were sacrificed by the end of the 7[th] day and specimens from the jejunum were dissected and processed for light and scanning electron microscopic examinations. Indomethacin-treated group exhibited jejunal mucosal injury. Light microscopic examination of this group, using H and E and toluidine blue- stained semithin sections showed distorted villi and sloughing of some of their apical parts with extrusion of many degenerated cells, intermingled with excess mucous. Some enterocytes appeared degenerated with loss of their regular arrangement, while the goblet cells appeared distended with excess mucous secretion. Increased cellular infiltration and edema of the villous core and in the lamina propria between the glands were noticed. Increased mucous secretion was also demonstrated by combined alcian blue-periodic acid Schiff reaction. Scanning electron microscope revealed alteration in the architecture of many villi which appeared short, blunt or with denuded surface and occasionally covered with membrane-like structure. The group of mice received arginine [group IV] revealed restoration of mucosal integrity in the form of regular villi with intact epithelial coverings including enterocytes and goblet cells. Some villi appeared shorter, while others showed partially denuded apical surface. Arginine evoked a remarkable cellular infiltration. Lymphocytes and macrophages were among the infiltrating cells and their roles were suggested to be vital in the healing process. Dietary L-arginine provided satisfactory protection against indomethacin-induced mucosal injury in mice, most probably via its role as a nitric oxide donor. So supplementation with dietary arginine is recommended

Interaction of bifidobacteria with the gut and their influence in the immune function

Bifidobacteria are predominant in the lumen of the large intestine and confer various health benefits on the host. They are also used in the preparation of new fermented milks (bioyogurts) or added to conventional yogurt to generate probiotic effects. The colonization of the gut by bacteria tends to be host specific due partly to the way in which bacteria adhere to the intestinal wall. Using a homologous strain of Bifidobacterium animalis in an experimental mouse model, we analyzed by immunofluorescence labelled-bacteria and transmission electronic microscopy the importance of the bacterial interaction with epithelial an immune cells associated to the gut, and the effect of feeding of B. animalis in the immune response. It was able to adhere and interact with both small and large intestine. In spite of this interaction with the gut, no modifications in the immune state (secretory or systemic response) were observed. A heterologous strain of Bifidobacterium adolescentis from human faeces, was neither incapable of binding to the intestine, nor influence the immune system activation, when it was administered during 2, 5 or 7 consecutive days; we believe that using a homologous strain, oral tolerance is developed even when the microorganism interacts with the immune cells associated with the intestine. However, we cannot ignore the beneficial effect of these microorganisms, especially in the prevention of intestinal infections. We think that this property exerted by bifidobacteria is more related to other mechanisms such as competitive inhibition, acid production or others, than enhancement of the immune state.

Enterocyte mitochondrial dysfunction due to oxidative stress.

The endogenous production of H2O2 in isolated rat intestinal mitochondria and oxidant induced damage to mitochondria were examined. There was an appreciable amount of H2O2 production in presence of succinate, glutamate and pyruvate, while the presence of rotenone with succinate further increased production. Superoxide generated by the X-XO system induced membrane permeability transition (MPT), calcium influx, lipid peroxidation and changes in membrane fluidity in mitochondria. A decreased mitochondrial ATPase activity and uncoupling of respiration was also observed. Spermine inhibited swelling induced by X-XO and also blocked the calcium influx and reversed the membrane fluidity changes.

Fucose and sialic acid contents of intestinal microvillus membranes from different animal species.

Fucose and sialic acid contents of intestinal microvillus membranes isolated from different animal species have been analysed. Expressed on protein basis, brush borders from fish contained considerably high amounts of sialic acid (298 +/- 16 nmole/mg protein), while rat, goat, sheep and guinea pig membranes showed 41-61 nmole/mg protein. Pig, frog, monkey rabbit and chicken membranes exhibited low levels of sialic acid (10-13 nmole/mg protein). Fucose content of the brush borders was quite high (203-212 nmole/mg protein) in frog and fish intestines. It was least in rabbit (54 +/- 3) and of intermediate levels (80-122 nmole/mg protein) in various other animal species analysed. Fucose to sialic acid molar ratio was less than 1 in fish microvillus membranes. In all other animal species, the ratio was however, greater than one and ranged between 1.65 and 15.20.