Model of nutritional supplementation with hepatotrophic factors increases cell proliferation in the liver of healthy rats

Foram avaliados dois protocolos de administração, em ratos sadios, de uma solução de fatores hepatotróficos (FH), composta por aminoácidos, vitaminas, sais minerais, glicose, insulina, glucagon e triiodotironina (T3). A solução foi administrada durante 10 dias, 40mg/kg/dia, i.p., em duas, grupo 2xFH (n=15), ou três doses, grupo 3xFH (n=15), diárias. Foram observados os efeitos na proliferação celular dos hepatócitos, na angiogênese e na matriz extracelular hepática, assim como as possíveis reações adversas. Os animais dos grupos 2xFH e 3xFH apresentaram aumento da massa hepática de 30,1% e 22,5%, respectivamente, em relação ao grupo-controle (CT; n=15). O índice de proliferação hepatocelular foi maior nos grupos 2xFH (1,4%) e 3xFH (1,2%) em relação ao grupo CT (0,53%), e a densitometria relativa do fator de crescimento do endotélio vascular pelo imunoblot não revelou diferença estatística entre os três grupos. Nos grupos 2xFH e 3xFH, houve redução do colágeno intersticial em relação ao grupo CT. A solução de FH estimulou o crescimento hepático e reduziu o volume de colágeno perissinusoidal. A administração em três doses diárias resultou em mortalidade de 26,7%, possivelmente pelo excessivo estresse da manipulação e pela menor adaptação fisiológica dos ratos, o que não ocorreu nos grupos 2xFH e CT. Para esse tipo de abordagem em ratos, o procedimento experimental mais apropriado, seguro, com melhor chance de adaptação dos animais e com resultados significativos é a aplicação dos FH em duas doses diárias.Two protocols of hepatotrophic factors (HF) administration, in solution composed by aminoacids, vitamins, mineral salts, glucose, insulin, glucagon, and triiodothyronine were evaluated in healthy rats. This solution was administered for 10 days, (40mg/kg/day) i.p., in two (group 2xFH; n=15) or three daily doses (group 3xFH n=15). The effects on hepatocytes cell proliferation, angiogenesis, and hepatic extracellular matrix, and also possible adverse reactions were analyzed. Animals of groups 2xFH and 3xFH presented an increase in hepatic mass of 30.1% and 22.5%, respectively, when compared rats of control group (CT; n=15). Hepatocellular proliferation index was higher in rats of groups 2xFH (1.4%) and 3xFH (1.2%) when compared to CT group animals (0.53%), and the relative densitometry of the vascular endothelial growth factor analyzed with immunoblot did not show a significant difference among the three groups. Rats of groups 2xFH and 3xFH showed a reduction of interstitial collagen when compared to CT rats. HF solution stimulated hepatic growth and reduced the volume of perisinusoidal collagen. Administration in three daily doses resulted in 26.7% mortality, possibly due to excessive stress from manipulation and lower physiological adaptation of rats, which did not occur in rats of groups 2xFH and CT. The more appropriate and safer experimental procedure for this approach in rats with higher chance of animal adaptation and significant results is the application of HF in two daily doses

Modulation of extracellular matrix by nutritional hepatotrophic factors in thioacetamide-induced liver cirrhosis in the rat

Nutritional substances associated to some hormones enhance liver regeneration when injected intraperitoneally, being denominated hepatotrophic factors (HF). Here we verified if a solution of HF (glucose, vitamins, salts, amino acids, glucagon, insulin, and triiodothyronine) can revert liver cirrhosis and how some extracellular matrices are affected. Cirrhosis was induced for 14 weeks in 45 female Wistar rats (200 mg) by intraperitoneal injections of thioacetamide (200 mg/kg). Twenty-five rats received intraperitoneal HF twice a day for 10 days (40 mL·kg-1·day-1) and 20 rats received physiological saline. Fifteen rats were used as control. The HF applied to cirrhotic rats significantly: a) reduced the relative mRNA expression of the genes: Col-α1 (-53%), TIMP-1 (-31.7%), TGF-β1 (-57.7%), and MMP-2 (-41.6%), whereas Plau mRNA remained unchanged; b) reduced GGT (-43.1%), ALT (-17.6%), and AST (-12.2%) serum levels; c) increased liver weight (11.3%), and reduced liver collagen (-37.1%), regenerative nodules size (-22.1%), and fibrous septum thickness. Progranulin protein (immunohistochemistry) and mRNA (in situ hybridization) were found in fibrous septa and areas of bile duct proliferation in cirrhotic livers. Concluding, HF improved the histology and serum biochemistry of liver cirrhosis, with an important reduction of interstitial collagen and increased extracelullar matrix degradation by reducing profibrotic gene expression

Efficacy of the dietary histone deacetylase inhibitor butyrate alone or in combination with vitamin A against proliferation of MCF-7 human breast cancer cells

The combined treatment with histone deacetylase inhibitors (HDACi) and retinoids has been suggested as a potential epigenetic strategy for the control of cancer. In the present study, we investigated the effects of treatment with butyrate, a dietary HDACi, combined with vitamin A on MCF-7 human breast cancer cells. Cell proliferation was evaluated by the crystal violet staining method. MCF-7 cells were plated at 5 x 10(4) cells/mL and treated with butyrate (1 mM) alone or combined with vitamin A (10 µM) for 24 to 120 h. Cell proliferation inhibition was 34, 10 and 46% following treatment with butyrate, vitamin A and their combination, respectively, suggesting that vitamin A potentiated the inhibitory activities of butyrate. Furthermore, exposure to this short-chain fatty acid increased the level of histone H3K9 acetylation by 9.5-fold (Western blot), but not of H4K16, and increased the expression levels of p21WAF1 by 2.7-fold (Western blot) and of RARβ by 2.0-fold (quantitative real-time PCR). Our data show that RARβ may represent a molecular target for butyrate in breast cancer cells. Due to its effectiveness as a dietary HDACi, butyrate should be considered for use in combinatorial strategies with more active retinoids, especially in breast cancers in which RARβ is epigenetically altered

Primary intraocular chondrosarcoma in a dog

A five-year-old male Cocker Spaniel was presented for evaluation of the right eye due to discomfort, abundant purulent discharge and progressive enlargement of the eyeball. The owner revealed that the right eye has appeared to be inflamed and smaller then the left eye for years. Ophthalmic examination revealed corneal perforation, buphthalmia and conjuctival hyperemia. Enucleating was performed due to signs of endophthalmitis and ocular discomfort. Histopathology revealed a multilobulated proliferation of chondrocytes producing hyaline cartilage with occasional pleomorphism and binucleate cells. A diagnosis of primary intraocular chondrosarcoma was done

Blood-brain Barrier Breakdown Following Gliotoxic Drug Injection In The Brainstem Of Wistar Rats [ruptura Da Barreira Hematoencefàlica Após Injeção De Droga Gliotóxica No Tronco Encefálico De Ratos Wistar]

Ethidium bromide (EB) causes local astrocytic disappearance, with glia limitans disruption and supposed blood-brain barrier (BBB) breakdown The aim of this study was to investigate the BBB integrity after the injection of 0.1% EB (group E) or 0.9% saline solution (group C) into cisterna pontis of Wistar rats. Brainstem fragments were collected from 24 hours to 31 days post-injection for ultrastructural study and GFAP immuno-histochemical staining. Some animals received colloidal carbon ink by intravenous route at the same periods. In rats from group C, there was no sign of astrocyte loss and no leakage of ink from blood vessels in the injection site. In group E, astrocyte disappearance began at 48 hours and some areas were still devoid of astrocytic processes 31 days after. Leakage of carbon particles was seen from 48 hours to 7 days in the EB-induced lesions. 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