Some Histopathological Findings in Dead Kihansi Spray Toads in Captivity

Raising of Kihansi spray toad (KST), Nectophrynoides asperginis, in captivity is associated with disorders that can be fatal. Since diagnosis of these disorders cannot be confirmed grossly, the current study was aimed at exploring histopathological findings in dead KSTs kept under captivity in Tanzania. Dead KSTs were immediately recovered, observed for gross changes, fixed in 10% neutral buffered formalin, processed routinely, and stained sections reviewed for histological changes. Observed infectious agents were strongyloides (25.3%), ciliates (1.7%), lungworms (0.6%), fungi (3.4%) and bacteria (5.1%) or mixed infections (9%) of these agents. Noted histopathological lesions in affected organs included infiltration of inflammatory cells, thickening of the epithelium, organ dilation, accumulation of organisms and dead tissue debris in the organs, hyperkeratosis, parakeratosis, and sloughing of the skin. Squamous metaplasia in various organs was the commonly observed non-infectious abnormality noted in 33.1% of the carcasses. It is concluded that there are several histological changes caused by infectious and non-infectious agents that are potential contributors of KST death in captivity.Keywords: Kihansi spray toad; parasites; pathology; captivity; immunit

Butyrate Induces Production of Heat Shock Protein 27, 70 and 90 and Protects Against Carbon Tetrachloride Hepatotoxicity in Rats

The liver plays important roles in the body including blood cell formation, metabolism of carbohydrates, proteins and lipids, detoxification, bile production and excretion, and hepatic regeneration. It is however prone to various hepatotoxins that cause damage and diseases including consumption of alcohol whose toxicity is at an alarmingly increasing prevalence globally. Since both butyrate and heat shock proteins (Hsps) can protect various body systems against several perturbations, we investigated whether butyrate protects the liver against carbon tetrachloride (CCl4) hepatotoxicity via production of Hsps. Rats were treated with sodium butyrate (SB) for 8 days then CCl4 on the 8th day and sacrificed 1 to 2 days later. Sacrificed animals were autopsied, liver samples taken, fixed in formalin and routinely processed. Tissue sections were stained with haematoxylin and eosin or anti-Hsp90, Hsp70 and Hsp27 monoclonal antibodies to assess morphological changes and expression of Hsps. Pretreatment with SB reduced the severity of CCl4 induced hepatotoxicity which was associated with expression of Hsp90, 70 and 27. It is concluded that the protective potency of butyrate against CCl4 hepatotoxicity is mediated, at least in part, through overexpression of Hsps

Time and Tissue Dependent Expression of Heat Shock Protein 27, 70 and 90 in Mice Following Hyperthermia

Heat shock response is rapidly induced to protect cells from irreversible injury by stabilizing cellular synthetic and metabolic activities. Particularly, the response differentially protects against stresses, infections and inflammations. While it could be time- and tissue-dependent, it is not established as to how it exhibits. This study explored the expression of heat shock protein (Hsp) 27, 70 and 90 in intestines, kidneys, livers and lungs of mice undergoing hyperthermia at 42°C for 1 hr and recovering for 1-72 hr. The expression of these Hsps was determined by immunohistochemical staining of formalin-fixed paraffin-embedded tissue sections. There was an increase in the expression of Hsp27, 70 and 90 that peaked at 6-12 hr and differentially declined at 48-72 hr. The peak expression was reached earlier in the lung and dropped sharply in the intestine while sustained for a longer time in the liver and kidney. At 72 hr only Hsp90 exhibited moderate expression in the lung and kidney. It is concluded that optimal expression of Hsps is time- and tissue- dependent and has narrow margin of peak expression in some tissues. This knowledge might contribute to designing therapeutic agents for curbing stresses, infections and inflammations that can be suppressed by Hsps

Over-expression of Heat Shock Protein 90 Reduces the Severity of Carbon Tetrachloride Hepatotoxicity in Rats

Cellular response to stress leads to production of heat shock proteins (Hsps) that are protective against various perturbations including stress, infection and inflammation. The liver is a victim to many body disturbances including intoxications and systemic diseases. Stemming on the ability of Hsps to protect an array of perturbations in various body systems, it is justifiable to explore their protective potency to the rat model of carbon tetrachloride (CTC)-induced hepatic toxicity. The current study therefore aimed at testing whether prior induction of Hsp90 could protect the liver against CTC. Rats were exposed to zinc sulphate (ZS) to induce Hsp90 then CTC for 8, 24, 48 or 72 hr. At the end of treatment, rats were sacrificed, autopsied, liver samples taken and fixed in formalin and routinely processed. Sectioned tissues were stained with hematoxylin and eosin or anti-Hsp90 monoclonal antibodies to assess morphological changes and Hsp90 expression respectively. CTC induced damage to the liver that was reduced by ZS. The ZS-mediated reduction of CTC-induced hepatic damage matched with ZS-induced over-expression of Hsp90. It is concluded that over-expression of Hsp90 is beneficial against CTC-induced hepatotoxicity

Hipertrofična osteopatija kao posljedica stranoga tijela u jednjaku psa - prikaz slučaja

Hypertrophic osteopathy is a pathological disease process that occurs secondary to intra thoracic lesions that are either pulmonary or non pulmonary in origin. A 6-year-old female German shepherd cross was presented with complaints of losing body condition, anorexia, lameness, and swollen limbs. Clinical examination revealed swelling of all four limbs which were hard and painless on palpation. Radiographic examination of the limbs and the thoracic cavity revealed, irregular periosteal new bone formation along the shafts of most of the long bones and an oval-shaped 6 cm diameter radio dense caudal mediastinal mass. At post-mortem examination, an oesophageal diverticulum was found, filled with foul smelling creamy exudates and a bone foreign body firmly adherent to the wall. Hypertrophic osteopathy secondary to oesophageal foreign body was diagnosed based on history, clinical examination, radiography, post-mortem picture and histopathology.Hipertrofična osteopatija patološki je proces koji se javlja sekundarno kao posljedica intratorakalnih lezija plućnog ili neplućnog podrijetla. Njemačka ovčarka u dobi od šest godina bila je primljena sa znakovima gubitka težine, anoreksije, šepanja i otečenih nogu. Kliničkom pretragom ustanovljene su tvrde, na palpaciju bezbolne otekline nogu. Radiografskom pretragom nogu i prsne šupljine ustanovljene su nepravilne periostealne novotvorine u većine dugih kostiju i ovalna radiološki gusta masa promjera šest cm u kaudalnom medijastinumu. Pri razudbi je ustanovljen divertikul jednjaka ispunjen pjenušavim eksudatom neugodna mirisa i koštano strano tijelo koje je čvrsto prianjalo na stijenku. Na osnovi anamneze, kliničke pretrage, radiografije, razudbe trupla i patohistološkoga nalaza dijagnosticirana je sekundarna hipertrofična osteopatija kao posljedica stranoga tijela u jednjak

The role of the heat shock response in the cytoprotection of the intestinal epithelium

Under normal conditions, the intestinal epithelial cells produce constitutive amount of heat shock proteins (Hsps) that are elevated following stressful stimuli. As the intestine is constantly exposed to variety of agents like diet, normal flora, infectious microorganisms, chemicals, and immune mediators, the expression of Hsps by the intestinal epithelial cells is therefore, multifactorial and the protective mechanisms are variable. The latter include restoration of unfolded or aggregated polypeptides to their native conformations, proteolysis of proteins too damaged to refold, assembly of proteins, translocation of proteins across membranes, stabilization of cell cytoskeleton and subsequent inhibition of pathogenic invasion, inactivation of intracellular parasites and prevention of persistent production of inflammatory cytokines that would otherwise lead to tissue damage. The aim of this study was to explore the various protective mechanisms of Hsps to the intestinal epithelium using Caco-2 cell model. The general experimental set up involved induction of Hsps production followed by a challenge with infectious Salmonella enteritidis. Hsps were mainly induced by thermal stress (42°C for 1 hr followed by 6 hr of recovery) and measured by immunostaining of Western blots. Protection against Salmonella infection was studied by assessing the levels of interleukin (IL) 8 that was measured by ELISA. In some experiments, Hsps were induced by fermentation products of gut flora such as butyrate and spent culture supernatants of lactobacilli. Results showed that the induced Hsps in various conditions did protect the cells against Salmonella enteritidis by suppressing the production of IL-8, which if it persists, causes tissue damage. It was interesting to note in one of the experiments that Hsps could also be induced following Salmonella enteritidis infection but not after exposure of the cells to its endotoxin. This phenomenon was linked with the stabilization of cell cytoskeleton and subsequent inhibition of invasion. However, it was observed that the induced Hsps could not benefit cells against Salmonella invasion. In addition to the production of Hsps, the fermentation products of gut flora (formate, propionate, and butyrate) were found to selectively and differentially modulate the growth characteristics, cellular metabolism, and differentiation of enterocyte-like Caco-2 cells in a concentration- and carbon atom-related fashion. Butyrate, with the highest number of carbon atom, was the most potent to induce markers of differentiation namely the transepithelial resistance and sucrase isomaltase. While it is known that cells may become considerably resistant to pathogenic invasion following differentiation, especially after induction of transepithelial resistance, in our study, the induced transepithelial resistance could not protect cells against Salmonella enteritidis invasion. It is concluded that the gut flora and their fermentation products play an important role in the protection of the intestinal epithelium. The protection is, at least in part, mediated by the production of Hsps. The mechanisms of Hsps in this protection include suppression of persistent production of inflammatory cytokines like IL-8 that would otherwise cause tissue damage and stabilization of barrier integrity and the subsequent inhibition of pathogenic invasion

Inhibition of Salmonella-induced IL-8 synthesis and expression of Hsp70 in enterocyte-like Caco-2 cells after exposure to non-starter lactobacilli

Oral administration of lactobacilli as probiotics is gaining importance in the treatment of intestinal inflammations. We investigated the effect of non-starter lactobacilli Lactobacillus casei subsp casei 2756, Lactobacillus curvatus 2775, and Lactobacillus plantarum 2142 as well as their spent culture supernatants (SCS) on Salmonella enteritidis 857 growth, interleukin (IL)-8 and heat shock protein 70 (Hsp70) synthesis in undifferentiated crypt-like and differentiated villus-like Caco-2 cells. The cells were infected with graded numbers of non-starter lactobacilli or S. enteritidis 857 for 1 h and allowed to recover for 24 h or exposed to 200 bacteria/cell for 1 h and allowed to recover for different periods of time. In another experiment S. enteritidis 857 was first pre-treated with SCS-lactobacilli for 1 h before infecting the cells. The levels of IL-8 and Hsp70 were assessed using sandwich ELISA and immunostaining of Western blots, respectively. The effect of SCS-lactobacilli on S. enteritidis 857 growth was evaluated by agar plate diffusion test. The non-starter lactobacilli induced a significant increase in the levels of both IL-8 and Hsp70. However, compared with the S. enteritidis 857 induced IL-8 synthesis, the levels of IL-8 induced by the lactobacilli at any equivalent bacterial number were far lower. After exposure of Caco-2 cells to S. enteritidis 857 pre-treated with SCS-lactobacilli, it appeared that their SCS inhibited the S. enteritidis 857 growth and IL-8 synthesis and in addition induced the expression of Hsp70. The differences in response of crypt- and villus-like Caco-2 cells are merely a reflection of their differentiation status. Our data suggest that the beneficial effect of non-starter lactobacilli to the intestinal inflammations might be associated with a decrease of the IL-8 levels. This effect could be mediated, at least in part, by the bacteria themselves or via a secreted antimicrobial product(s) either directly against the pathogens or indirectly through the synthesis of Hsp70

Sodium arsenite reduces severity of dextran sulfate sodium-induced ulcerative colitis in rats

The histopathological features and the associated clinical findings of ulcerative colitis (UC) are due to persistent inflammatory response in the colon mucosa. Interventions that suppress this response benefit UC patients. We tested whether sodium arsenite (SA) benefits rats with dextran sulfate sodium (DSS)-colitis. The DSS-colitis was induced by 5% DSS in drinking water. SA (10 mg/kg; intraperitoneally) was given 8 h before DSS treatment and then every 48 h for 3 cycles of 7, 14 or 21 d. At the end of each cycle rats were sacrificed and colon sections processed for histological examination. DSS induced diarrhea, loose stools, hemoccult positive stools, gross bleeding, loss of body weight, loss of epithelium, crypt damage, depletion of goblet cells and infiltration of inflammatory cells. The severity of these changes increased in the order of Cycles 1, 2 and 3. Treatment of rats with SA significantly reduced this severity and improved the weight gain