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We investigated whether intervention with antioxidant vitamins C and E in enteral feeding influenced oxidative stress and clinical outcome in critically ill patients. Two-hundred-sixteen patients expected to require at least 10 days of enteral feeding completed the study. One-hundred-five patients received enteral feeding supplemented with antioxidants, and 111 control patients received an isocaloric formula. Plasma lipoperoxidation (by thiobarbituric acid reactive substances [TBARS] and prostaglandin F(2alpha) isoprostane levels), low-density lipoprotein (LDL) oxidizability, and LDL tocopherol content were determined at baseline and at the end of the 10-day period. The clinical 28-day outcome was also assessed. Plasma TBARS and isoprostanes were 5.33 +/- 1.26 nM/mL and 312 +/- 68 pg/mL, respectively, before treatment and 2.42 +/- 0.61 nM/mL and 198 +/- 42 pg/mL after intervention (P < 0.01 for both comparisons). Antioxidants improved LDL resistance to oxidative stress by approximately 30% (the lag time before treatment was 87 +/- 23 min and was 118 +/- 20 min after treatment; P < 0.04). There was a significantly reduced 28-day mortality after antioxidant intervention (45.7% in the antioxidant group and 67.5% in the regular-feeding group; P < 0.05). Isoprostanes may provide a sensitive biochemical marker for dose selection in studies involving antioxidants.

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Ulcerative colitis (UC) and Crohn's disease (CD) are the major forms of inflammatory bowel diseases (IBD) in man. Despite some common features, these forms can be distinguished by different genetic predisposition, risk factors and clinical, endoscopic and histological characteristics. The aetiology of both CD and UC remains unknown, but several evidences suggest that CD and perhaps UC are due to an excessive immune response directed against normal constituents of the intestinal bacterial flora. Tests sometimes invasive are routine for the diagnosis and care of patients with IBD. Diagnosis of UC is based on clinical symptoms combined with radiological and endoscopic investigations. The employment of non-invasive biomarkers is needed. These biomarkers have the potential to avoid invasive diagnostic tests that may result in discomfort and potential complications. The ability to determine the type, severity, prognosis and response to therapy of UC, using biomarkers has long been a goal of clinical researchers. We describe the biomarkers assessed in UC, with special reference to acute-phase proteins and serologic markers and thereafter, we describe the new biological markers and the biological markers could be developed in the future: (1) serum markers of acute phase response: The laboratory tests most used to measure the acute-phase proteins in clinical practice are the serum concentration of C-reactive protein and the erythrocyte sedimentation rate. Other biomarkers of inflammation in UC include platelet count, leukocyte count, and serum albumin and serum orosomucoid concentrations; (2) serologic markers/antibodies: In the last decades serological and immunologic biomarkers have been studied extensively in immunology and have been used in clinical practice to detect specific pathologies. In UC, the presence of these antibodies can aid as surrogate markers for the aberrant host immune response; and (3) future biomarkers: The development of biomarkers in UC will be very important in the future. The progress of molecular biology tools (microarrays, proteomics and nanotechnology) have revolutionised the field of the biomarker discovery. The advances in bioinformatics coupled with cross-disciplinary collaborations have greatly enhanced our ability to retrieve, characterize and analyse large amounts of data generated by the technological advances. The techniques available for biomarkers development are genomics (single nucleotide polymorphism genotyping, pharmacogenetics and gene expression analyses) and proteomics. In the future, the addition of new serological markers will add significant benefit. Correlating serologic markers with genotypes and clinical phenotypes should enhance our understanding of pathophysiology of UC.

Reproductive dysfunction is a consequence of diabetes, but the underlying mechanisms are poorly understood. This study investigated the histological and molecular alterations in the testes of rats injected with streptozotocin at prepuperal (SPI rats) and adult age (SAI rats) to understand whether diabetes affects testicular tissue with different severity depending on the age in which this pathological condition starts. The testes of diabetic animals showed frequent abnormal histology, and seminiferous epithelium cytoarchitecture appeared altered as well as the occludin distribution pattern. The early occurrence of diabetes increased the percentage of animals with high number of damaged tubules. The interstitial compartment of the testes was clearly hypertrophic in several portions of the organs both in SPI and SAI rats. Interestingly, fully developed Leydig cells were present in all the treated animals although abnormally distributed. Besides the above-described damages, we found a similar decrease in plasma testosterone levels both in SPI and SAI rats. Oxidative stress (OS) is involved in the pathogenesis of various diabetic complications, and in our experimental models we found that manganese superoxide dismutase was reduced in diabetic animals. We conclude that in STZ-induced diabetes, the altered spermatogenesis, more severe in SPI animals, is possibly due to the effect of OS on Leydig cell function which could cause the testosterone decrease responsible for the alterations found in the seminiferous epithelium of diabetic animals.

SummaryA wide variety of environmental contaminants exert estrogenic actions in wildlife, laboratory animals, and in human beings through binding to nuclear estrogen receptors (ERs). Here, the mechanism(s) of bisphenol A (BPA) to induce cell proliferation and the occurrence of its bioremediation by treatment with laccase are reported. BPA, highly present in natural world and considered as a model of environmental estrogen action complexity, promotes human cancer cell proliferation via ERa-dependent signal transduction pathways. Similar to 17b-estradiol, BPA increases the phosphorylation of both extracellular regulated kinase and AKT. Specific inhibitors of these kinase completely block the BPA effect on cancer cell proliferation. Notably, high BPA concentrations (i.e., 0.1 and 1 mM) are cytotoxic even in ERa-devoid cancer cells, indicating that an ERa-independent mechanism participates to BPA-induced cytotoxicity. On the other hand, BPA oxidation by laccase impairs the binding of this environmental estrogen to ERa loosing at all ERa-dependent effect on cancer cell proliferation. Moreover, the laccase-catalyzed oxidation of BPA reduces the BPA cytotoxic effect. Thus, laccase appears to impair BPA action(s), representing an invaluable bioremediation enzyme.2008 IUBMB IUBMB Life, 60(12): 843-852, 2008

Combined administration of Vitamin E and C lowered inflammation and improved insulin action through a rise in non-oxidative glucose metabolism.

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