Biochemical and histological changes in the heart of post-partum rats exposed to Natron.

BACKGROUND: The customary puerperal practice of Natron consumption has been identified as one of the predisposing factors in the etiology of peripartum cardiomyopathy (PPCM). This study was designed to investigate the effect of Natron in postpartum Wistar albino rats. METHODS: A total of 30 postpartum Wistar rats were exposed to different doses (50mg/kg, 100mg/kg, 200mg/kg and 300mg/kg) of Natron for 28days. After the treatment, we carried out biochemical analyses and histological evaluations of kidney, liver and heart. RESULTS: The study revealed that the exposure of postpartum rats to 100mg/kg of Natron and above significantly (p<0.05) increase the cardiac markers; myoglobin, creatine kinase-MB, troponin I and T as compared with control. The result of liver function indicated no significant difference in alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, albumin and total protein of the Natron treated groups as compared with control. However, at higher doses, the levels of total protein, globulin and alkaline phosphatase activity were significantly increased in comparison to the control. There was no significant difference in the kidney function markers of the treatment groups as compared with control. Histological examinations revealed no changes in the kidney of the treated groups. Mild portal triaditis was observed in the liver of the treated rats. The heart of the rats administered ≥100mg/kg of Natron showed myocyte hypertrophy. CONCLUSION: The study demonstrated that the administration of Natron for 28days caused changes in the heart of postpartum rats and thus may contribute to the pathogenesis of PPCM.

Nano-formulation for topical treatment of precancerous lesions: skin penetration, in vitro, and in vivo toxicological evaluation.

With the aim of improving the topical delivery of the antineoplastic drug 5-fluorouracil (5FU), it was loaded into ultradeformable liposomes composed of soy phosphatidylcholine and sodium cholate (UDL-5FU). The liposome populations had a mean size of 70 nm without significant changes in 56 days, and the ultradeformable formulations were up to 324-fold more elastic than conventional liposomes. The interaction between 5FU and the liposomal membrane was studied by three methods, and also release profile was obtained. UDL-5FU did penetrate the stratum corneum of human skin. At in vitro experiments, the formulation was more toxic on a human melanoma-derived than on a human keratinocyte-derived cell line. Cells captured liposomes by metabolically active processes. In vivo toxicity experiments were carried out in zebrafish (Danio rerio) larvae by studying the swimming activity, morphological changes, and alterations in the heart rate after incubation. UDL-5FU was more toxic than free 5FU. Therefore, this nano-formulation could be useful for topical application in deep skin precancerous lesions with advantages over current treatments. This is the first work that assessed the induction of apoptosis, skin penetration in a Saarbrücken penetration model, and the toxicological effects in vivo of an ultradeformable 5FU-loaded formulation.

Sodium cholate-templated blue light-emitting Ag subnanoclusters: in vivo toxicity and imaging in zebrafish embryos.

We report a novel green chemical approach for the synthesis of blue light-emitting and water-soluble Ag subnanoclusters, using sodium cholate (NaC) as a template at a concentration higher than the critical micelle concentration (CMC) at room temperature. However, under photochemical irradiation, small anisotropic and spherically shaped Ag nanoparticles (3-11 nm) were obtained upon changing the concentration of NaC from below to above the CMC. The matrix-assisted laser desorption ionization time-of-flight and electrospray ionization mass spectra showed that the cluster sample was composed of Ag4 and Ag6. The optical properties of the clusters were studied by UV-visible and luminescence spectroscopy. The lifetime of the synthesized fluorescent Ag nanoclusters (AgNCs) was measured using a time-correlated single-photon counting technique. High-resolution transmission electron microscopy was used to assess the size of clusters and nanoparticles. A protocol for transferring nanoclusters to organic solvents is also described. Toxicity and bioimaging studies of NaC templated AgNCs were conducted using developmental stage zebrafish embryos. From the survival and hatching experiment, no significant toxic effect was observed at AgNC concentrations of up to 200 µL/mL, and the NC-stained embryos exhibited blue fluorescence with high intensity for a long period of time, which shows that AgNCs are more stable in living system.

Investigation of necessity of sodium cholate and minimal required amount of cholesterol for dietary induction of atherosclerosis in microminipigs.

Recently we established a Microminipig (MMPig) model of atherosclerosis induced by high fat/high cholesterol (Cho) diet containing sodium cholate (SC), which is known to cause hepatotoxicity. In the present study, we investigated whether SC is necessary as well as the minimum amount of dietary Cho required to induce atherosclerosis. Experiment A: Six MMPigs were divided into three groups of two, and were fed for 12 weeks as follows: a diet containing 12% fat and 5% Cho with or without 0.7% SC, or the diet including 12% fat and 0.5% Cho with SC. Although each diet induced a similar degree of hypercholesterolemia and atherosclerosis, the liver weights and severity of fatty change in the hepatocytes were maximal in the animals fed 5% Cho and SC. Experiment B: Six MMPigs were divided into two groups of three, and fed for 18 weeks as follows: normal diet, and a diet of increasing dose of Cho (0.03, 0.1, 0.3, 0.5, 1.5 and 5%) for the initial 14 weeks and 0.5% Cho/12% fat diet for the final four weeks. Serum levels of total Cho and low-density lipoprotein-Cho reached a plateau with 0.5% Cho diet, suggesting that the minimum amount of Cho required is 0.5%. The absorption of Cho in MMPigs was enhanced by 0.5% Cho and 12% fat diet compared to the 5% Cho-alone diet. In conclusion, a diet with 0.5% Cho and 12% fat without SC appears to be sufficient to induce atherosclerosis in the MMPig.

Improving the absorption of earthworm fibrinolytic enzymes with mucosal enhancers.

Earthworm fibrinolytic enzymes (EFEs), an ideal drug for cardiovascular diseases, have a very low oral bioavailability. In order to improve the absorption of EFEs, six different enhancers were selected to increase the intestinal absorption of EFEs. In vitro (Caco-2 monolayers) and in vivo (mice) experiments were carried out to find the optimum concentration and action time of these enhancers for EFE absorption. We found that EFEs could be transported into blood across intestinal endothelial membrane after administration via intragastric administration with low bioavailability. These results obtained from in vitro experiments were similar to those in vivo. Moreover, menthol and glucose showed absorption enhancement properties with a relatively low cytotoxicity.

New findings on melatonin absorption and alterations by pharmaceutical excipients using the Ussing chamber technique with mounted rat gastrointestinal segments.

We examined how melatonin absorption was affected by pharmaceutical excipients using the Ussing chamber technique with mounted rat gastrointestinal (GI) segments. Melatonin absorption occurs throughout the GI tract, with the greatest absorption being in the rectum and ileum and the least in the stomach. Melatonin can be classified as a low permeability drug. P-glycoprotein (P-gp) does not affect melatonin absorption but transported rhodamine 123, a well-known P-gp substrate. The possibility of saturating P-gp by melatonin was excluded. Sodium cholate (0.5%) increased melatonin absorption, but decreased absorption at higher concentrations (1.0% and 5.0%). Sodium oleate (0.5% and 1.0%) consistently decreased melatonin absorption. Pharmaceutical excipients increased the absorption of Lucifer yellow (100 microg/mL), a paracellular probe but decreased the absorption of melatonin above the critical micelle concentration (cmc), suggesting that melatonin was transported mainly by transcellular pathway. Sodium cholate and sodium oleate, when above the cmc, resulted in micellar complexes as revealed by (1)H NMR spectra and particle size distribution. Histology tests showed mucosal damage of jejunum tissues in the presence of these excipients. The balance of tissue damage by the formation of micellar complexes could affect the melatonin absorption. This information on melatonin absorption behaviors and its modulation by pharmaceutical excipients can be used in further oral dosage formulations to affect circadian rhythm.

Mild hepatic fibrosis in cholesterol and sodium cholate diet-fed rats.

To date, the majority of research on hypercholesterolemia has focused on the effects of a high cholesterol diet on atherosclerosis and coronary heart disease. The toxic effects of cholesterol on the liver and the relationship between the intake of a high cholesterol diet and hepatic fibrosis, however, have not been investigated clearly or histopathologically. Male Wistar rats were fed a diet supplemented with 1.0% cholesterol and 0.3% sodium cholate for 12 weeks. Rats were sacrificed and analyzed via blood biochemistry, traditional microscopy and immunohistochemistry. Following the feeding of this diet, the rates of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and total cholesterol in the rats were elevated consistently from week 3 and throughout the remainder of the experiment. From microscopic observation, hepatic necrosis, macrophage infiltration and steatosis increased markedly throughout the experiment. Hepatic fibrosis and myofibroblast proliferation were detected at weeks 9 and 12. Mast cell appearance was proportional to the degree of hepatic damage. These findings suggest that hepatic fibrosis is inducible by a high cholesterol diet and is likely the result of the interaction between several different cell types (i.e., macrophages, myofibroblasts, and mast cells) in an inflammatory milieu. Hypercholesterolemia should be considered as a risk factor for hepatic fibrosis as well as atherosclerosis and coronary artery disease.