Adaptive hepatic changes in mild stenosis of the common bile duct in the rat

Swimming Attenuates Muscle Wasting and Mediates Multiple Signaling Pathways and Metabolites in CT-26 Bearing Mice

Objectives: To investigate the effects of swimming on cancer induced muscle wasting and explore its underlying mechanism in CT-26 bearing mice.

Methods: BALB/c mice (n = 16) injected with CT-26 cells were divided into two groups, including Tumor group (n = 8) and Swimming group (n = 8). Another 8 un-injected mice were set as Control group. Mice in Swimming group were subjected to physical training for swimming twice per day for 30 min intervals and 6 days per week for a total of 4 weeks. The tumor volume was monitored every 3 days and tumor weight was measured at the end of experiment. The changes of muscle function, pathological and cell apoptosis of quadriceps muscles were further assessed, and its underlying mechanisms were further explored using multiple biological technologies.

Results: Swimming obviously alleviated tumor volume and weight in CT-26 bearing mice. Moreover, swimming attenuated the decrease of muscle tension, autonomic activities, and increase of muscle atrophy, pathological ultrastructure, as well as cell apoptosis of quadriceps muscles in CT-26 bearing mice. Furthermore, swimming significantly down-regulated the protein expression of NF-κB, p-NF-κB, TNF-α, IL-1β, IL-6 and Bax, while up-regulated the expression of Bcl-2. Further differential expressed metabolites (DEMs) analysis identified a total of 76 (in anion mode) and 330 (in cationic mode) DEMs in quadriceps muscles of CT-26 bearing mice after swimming, including taurochenodeoxycholic acid, taurocholic acid, ascorbic acid and eicosapentaenoic acid.

Conclusion: Swimming attenuates tumor growth and muscle wasting, and by suppressing the activation of NF-κB signaling pathway mediated inflammation, reducing the level of Bax medicated cell apoptosis, as well as modulating multiple metabolites might be the importantly underlying mechanisms.

Bile salts and their importance for drug absorption

Bile salts are present in the intestines of humans as well as the animals used during the development of pharmaceutical products. This review provides a short introduction into the physical chemical properties of bile salts, a description of the bile concentration and composition of bile in different animal species and an overview of the literature investigating the influence of bile salts on the in vivo performance of different compounds and drug formulations. Generally, there is a positive effect on bioavailability when bile is present in the gastro-intestinal tract, independent of the formulation systems, e.g. suspensions, solutions, cyclodextrin complexes or lipid based formulations, but a few exceptions have also been reported.

Update on a Pharmacokinetic-Centric Alternative Tier II Program for MMT-Part II: Physiologically Based Pharmacokinetic Modeling and Manganese Risk Assessment

Recently, a variety of physiologically based pharmacokinetic (PBPK) models have been developed for the essential element manganese. This paper reviews the development of PBPK models (e.g., adult, pregnant, lactating, and neonatal rats, nonhuman primates, and adult, pregnant, lactating, and neonatal humans) and relevant risk assessment applications. Each PBPK model incorporates critical features including dose-dependent saturable tissue capacities and asymmetrical diffusional flux of manganese into brain and other tissues. Varied influx and efflux diffusion rate and binding constants for different brain regions account for the differential increases in regional brain manganese concentrations observed experimentally. We also present novel PBPK simulations to predict manganese tissue concentrations in fetal, neonatal, pregnant, or aged individuals, as well as individuals with liver disease or chronic manganese inhalation. The results of these simulations could help guide risk assessors in the application of uncertainty factors as they establish exposure guidelines for the general public or workers.

Histologic evaluation of rats' liver after Croton cajucara Benth (sacaca) administration

PURPOSE: To evaluate the hepatic effect of Croton cajucara Benth (sacaca) herbal extract in rats. METHODS: 60 Wistar rats (Rattus novergicus albinus) were used, weighing between 250 and 350 g. The animals were distributed randomically in 2 groups: GS - animals which received daily 0,1 ml/ 100 g of sacaca herbal extract through gavage, and GA -animals which received daily 0,1 ml/100g of distilled water through gavage. These were distributed in 3 subgroups with 10 animals, according to theirs euthanasia dates, which were 14th, 28th and 56th day of treatment. RESULTS: Architectural alterations were not observed, however when it was analyzed the presence or absence of necrosis, it was observed in 50% of GS28 subgroup and 90% of subgroup. In 50% of the animals from GS28 subgroup and 90% of GS56 subgroup was observed vast degeneration areas and zonal necrosis, regarding center-lobular veins alterations, there were no alterations in any of the groups CONCLUSION: The Croton cajucara Benth (sacaca) herbal extract in this experiment caused degeneration and hepatic necrosis, suggesting dose-dependent action.

Reversible cholestasis induced by experimental partial obstruction of the bile duct

The aim of this investigation was to reproduce in rats a partial stenosis of the common bile duct to analyze early liver functional and morphometric changes. The hepatic transport kinetics of sulfobromophthalein (organic anion) and rhodamine B (organic cation) was also investigated, and compartmental analysis of both compounds was performed. The humoral parameters of liver function indicated a cholestasis after 2 days of surgery, which reverted to reach normal values on the seventh day. Tumor necrosis factor alpha serum levels showed a tendency to increase on the second day of stenosis (7 out of 14 rats) while white blood cells increased on the second day of stenosis, and turned to normal levels on the seventh day. Histological studies showed increased volume of portal areas and ductular proliferation, which did no revert during the time of the study (up to 7 days post-op). Conversely, a moderate fibrosis and leukocyte infiltrates in portal areas predominated on the second day of stenosis, but normalized on the seventh day. Bile flow was considerably diminished on the second day of partial obstruction as compared to controls. The mean recovery in bile of sulfobromophthalein after 1h of being injected was low on the second day of stenosis, but normalized on the seventh day. Conversely, that of rhodamine B was very low in all animals. Sulfobromophthalein kinetics showed that hepatic uptake and canalicular excretion were impaired during the second but normalized on the seventh day of stenosis. However, rhodamine B kinetics showed that this compound was poorly excreted in all groups although canalicular excretion increased on the second day. The results suggested a model of obstructive cholestasis induced by the experimental stenosis of the bile duct which was not only reversible but also implicates the role of hepatic inflammation.