Effect of NFkappaB inhibition by CAPE on skeletal muscle ischemia-reperfusion injury.

BACKGROUND/AIMS: Nuclear factor kappa B (NFkappaB) plays important role in the pathogenesis of skeletal muscle ischemia/reperfusion (I/R) injury. Caffeic acid phenyl ester (CAPE), a potent NFkappaB inhibitor, exhibits protective effects on I/R injury in some tissues. In this report, the effect of CAPE on skeletal muscle I/R injury in rats was studied. METHODS: Wistar rats were submitted to sham operation, 120-min hindlimb ischemia, or 120-min hindlimb ischemia plus saline or CAPE treatment followed by 4-h reperfusion. Gastrocnemius muscle injury was evaluated by serum aminotransferase levels, muscle edema, tissue glutathione and malondialdehyde measurement, and scoring of histological damage. Apoptotic nuclei were determined by a terminal uridine deoxynucleotidyl transferase dUTP nick end labeling assay. Muscle neutrophil and mast cell accumulation were also assessed. Lipoperoxidation products and NFkappaB were evaluated by 4-hydroxynonenal and NFkappaB p65 immunohistochemistry, respectively. RESULTS: Animals submitted to ischemia showed a marked increase in aminotransferases after reperfusion, but with lower levels in the CAPE group. Tissue glutathione levels declined gradually during ischemia to reperfusion, and were partially recovered with CAPE treatment. The histological damage score, muscle edema percentage, tissue malondialdehyde content, apoptosis index, and neutrophil and mast cell infiltration, as well as 4-hydroxynonenal and NFkappaB p65 labeling, were higher in animals submitted to I/R compared with the ischemia group. However, the CAPE treatment significantly reduced all of these alterations. CONCLUSIONS: CAPE was able to protect skeletal muscle against I/R injury in rats. This effect may be associated with the inhibition of the NFkappaB signaling pathway and decrease of the tissue inflammatory response following skeletal muscle I/R.

Deficiência da vitamina A / Vitamin A deficiency

A integridade funcional do ser humano depende, entre outros fatores, de um adequado equilíbrio orgânico. Nesse contexto, os micronutrientes desempenham papel essencial. Nesta revisão, aborda-se a vitamina A de forma ampla e concisa, enfatizando as repercussões deletérias decorrentes de sua deficiência sobre o organismo e sua interação positiva em situações clínicas específicas.

Inhibitory effects of lutein and lycopene on placental glutathione S-transferase-positive preneoplastic lesions and DNA strand breakage induced in Wistar rats by the resistant hepatocyte model of hepatocarcinogenesis.

Inhibitory effects of lutein (LUT) and lycopene (LYC) on hepatic preneoplastic lesions (PNLs) and DNA strand breakage induced in Wistar rats by the resistant hepatocyte (RH) model of hepatocarcinogenesis were investigated. Animals received by gavage during 8 consecutive weeks on alternate days 70 mg/kg body weight of LUT or LYC. Rats treated with only corn oil and submitted to this model were used as controls. At the end of the experiment, treatment of the animals with LUT or LYC resulted in an increase in the respective liver carotenoid concentrations (P < 0.05). Moreover, it tended to reduce the incidence, total number, and multiplicity of hepatocyte nodules compared with the control group, although the differences did not reach statistical significance. Animals treated with LUT or LYC presented also a lower number of hepatic placental glutathione S-transferase-positive (GST-P) PNLs (P < 0.05), which were smaller (P < 0.05) and occupied a smaller area of the liver section (P < 0.05). Finally, hepatic DNA strand breakage evaluated by the comet assay was lower (P < 0.05) in carotenoid-treated animals when compared with the control group. Therefore, the results indicate that LUT and LYC represent promising chemopreventive agents during hepatocarcinogenesis and whose anticarcinogenic actions could be related to a protection against DNA instability.

Nutrologia: nutriçäo clínica / Nutrology: clinical nutrition

Nutrologia é a especialidade médica que estuda a fisiopatologia, o diagnóstico, o tratamento de moléstias nutricionais e problemas médicos correlatos. Näo se restringe ao estudo de quadros clínicos resultantes de problemas primários ou secundários de ingestäo ou metabolismo de nutrientes. Inúmeras situaçöes clínicas envolvem cuidados nutricionais que merecem especial atençäo dos médicos