Effect of nitric oxide release from NOR-3 on urea synthesis, viability and oxygen consumption of rat hepatocyte cultures.

As nitric oxide is considered a mediator of liver oxidative metabolism during sepsis, we studied the effects of exogenous nitric oxide, produced by NO-donor, (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR-3), on cell viability, urea biosynthesis and oxygen consumption in rat hepatocyte cultures. Nitric oxide release from NOR-3 was studied using 4,5-diaminofluorescein diacetate. Urea levels were measured by the spectrophotometric method. Cell viability was determined by the MTT test and trypan blue exclusion test, whereas oxygen consumption was measured by a polarographic technique. After 2 h treatment, NOR-3 induced an increase in the levels of nitric oxide. After 2 h of treatment and 24 h after the end of the treatment with NOR-3, both cell viability and urea synthesis were significantly reduced in comparison to the controls for NOR-3 concentrations equal to or greater than 50 microM. A reduction in oxygen consumption was observed in hepatocytes after 40 min treatment with 100 microM NOR-3, even if the cell viability was unchanged. Reduction of oxygen consumption is an early indicator of the metabolic alterations in hepatocytes exposed to nitric oxide. These findings suggest that nitric oxide accumulation acts on hepatocyte cultures inducing cell death and reduction of urea synthesis after 2 hours.

Olive oil and hyperthermal water bigels for cosmetic uses.

Bigels are biphasic systems produced with an organogel (or oleogel) and a hydrogel mixed together at high shear rates. These systems are promising for different uses, among them the formulation of new cosmetic matrices for cosmetic agents delivery is under investigation. In the present paper, a common cosmetic formulation for skin care was enriched with increasing fractions of monoglycerides of fatty acids/olive oil organogels, in order to understand the rheology and the microstructure of these systems. Small amplitude oscillation tests, NMR-self diffusion analysis, contrast phase microscopy and electric conductivity confirmed that the addition of the organogel caused a microstructural change of the starting material, which turned from O/W to a more complex system where, probably, a matrix-in-matrix structure is present at the highest fractions of added organogel.

Oxidation of human red blood cells by a free radical initiator: effects on rheological properties.

The main aim of this study was the investigation of the rheological properties of Red Blood Cells (RBCs) obtained from subjects admitted to blood donors, associated with the lipid profile of High-Density Lipoprotein Cholesterol (HDL-C), Low-Density Lipoprotein Cholesterol (LDL-C), Triglyceride (TG) and Total Cholesterol (TOT-C). The deformability index of RBCs was determined by using a Dynamic Stress Rheometer (DSR-500) under oxidative injury induced by 2.2'-azo-bis (2-amidinopropane) dihydrochloride (AAPH). An increased rigidity of RBCs in subjects with borderline level of hyperlipidemia was found, compared with the control group. In order to explain the reason for the reduced deformability, a borderline group was studied for the evaluation of anionic permeability on membrane, haemolysis and morphological changes induced by AAPH, as well as ThioBarbituric Acid Reactive Substances (TBARs) generation. Haemolysis by AAPH indicated a decrease of globular resistance in the borderline group, furthermore, the elevated values of TBARs suggested lipid peroxidative damage to the RBCs membrane associated with morphological changes and anion permeability alterations. Our study shows the correlation between biochemical and morphological parameters of RBCs and their rheological behavior during oxidative injury. Rheological studies might be useful as a clinical and diagnostic monitoring technique and provide support for further research.

Low molecular weight peptide from calf's liver mitochondrial DNA: structure and effect on DNA as a template.

A peptide fraction from the mitochondrial DNA of calf's liver was isolated using Drouin's method (1). This peptide fraction, which was extracted at pH 9.5 from an extensively purified mitochondrial DNA (2), has been shown to exert an in vitro regulatory role on the transcription and duplication activity of DNA (3). The same fraction also binds with mitochondrial DNA with a high affinity constant and stabilizes DNA from calf's thymus against thermal denaturation. The peptides from mitochondrial DNA have been subfractionated by fingerprinting-like techniques and one of them has been sequenced.

Effect of thyroid hormones and their analogues on the mitochondrial calcium transport activity.

In this paper the authors studied the effects of thyroid hormones and their structural analogues on the mitochondrial calcium transport activities. The thyroid hormones, 3,5,3' L-triiodothyronine (LT3) and 3,5,3'5' L-tetraiodothyronine (LT4) at physiological intracellular concentrations between 7.2 and 9 nM, decouple total Ca++ transport, as well as inhibit the passive transport of Ca++, either due to oxidation of pyruvate, malate or succinate or after inhibition with rotenone. The optical isomers 3,5,3' D-triiodothyronine (DT3) and 3,5,3',5' D-tetraiodothyronine (DT4) are less effective at all the used concentrations. Furthermore the structural analogues 3,3',5' L-triiodothyronine (LrT3), 3,5-dicloro, 3',5' L-diiodothyronine (LDiClT2) and 3,5 L-diiodothyronine (LT2) furnished even less effects on the same activities. The effect of the thyroid hormones and of their structural analogues has revealed that the mitochondrial calcium transport may be influenced both by a stereospecific interaction between hormones and protein ligands and by a lipophilic chaotropic action on the mitochondrial membranes lipids. In this context it is interesting to consider that both thyroid hormones and Ca++ transport activity are interacting with the energetic metabolism by means of phosphorylation and substrate oxidation mechanism.

[Effect of sulphurous Bioglea on psoriasis]. / Effetto delle Bioglee solfuree su lesioni psoriasiche.

OBJECTIVE: The efficacy of biological sulphurous Bioglee on psoriasis was investigated using an organic matrix derived from the metabolism of microflora growing in shallow hyper thermal waters possessing high sulphur concentrations and in thermal mud at Guardia Piemontese-Acquappesa (CS). Such a matrix forms part of the "Sulphuretum" ecological matrix which is dominated by cyanobacteria and sulfobacteria. The effect of this matrix on psoriasis was evaluated through the typical symptoms such as desquamation, cutaneous erythema and itching. METHODS: The study was carried out on 20 patients wich gave informed consent, suffering from psoriasis. Image analysis was used to monitor the intensity of psoriasic lesions prior to and at the conclusion of the therapy which consisted of topical applications of the thermal matrices twice a day for 12 days. RESULTS: Image analysis illustrated a reduction in the intensity of psoriasic lesions at the conclusion of the therapy with significant reductions in desquamation, erythema and itching. CONCLUSIONS: The anti-psoriasic action of the thermal matrix used in this study may be attributable to the substances such as carotene, hydro and lipo-soluble vitamins and naturally occuring phytosterols. These substances may not only be anti-inflammatory but may also work synergistically with the mineral components of the thermal matrix to attenuate the symptoms of psoriasis.

Evaluation of natural reductants protecting red blood cell membranes against oxidative damage in psoriatic patients.

OBJECTIVE: Psoriasis is a chronic skin disease and one of its main causes could be the oxidative stress. The use of natural reductants, in the treatment of several diseases, is well known but the effects of such treatments on the chronic psoriasis are not clear. The aim of this study is to evaluate the efficacy of the treatment with organic matrix, deriving from micro-flora, grown in shallow hyper thermal water tubs at Guardia Piemontese-Acquappesa (CS) Italy, in patients affected by moderate psoriasis. MATERIALS AND METHODS: The study has been performed on 10 subjects with plaque psoriasis and on 10 healthy control subjects. Clinical severity of psoriasis was determined according to Psoriasis and Severity Index (PASI). The treatment efficacy was observed trough the evaluation of membrane fluidity, by fluorescence polarization, lipid peroxidation, anion permeability and haemolysis in red blood cells. RESULTS: After 12 days of patients' treatment, a significant reduction of PASI score was observed, this result is supported by a significant improvement of all studied parameters. CONCLUSIONS: The results, obtained by the evaluation of all studied parameters in patients treated with the organic matrix, are evidence of the efficacy of this treatment, according to PASI evaluation. Thus our results, suggest that this therapeutic line may be useful in the treatment of moderate psoriatic lesions and also in improving the life quality of psoriatic patients.

Angiotensin II regulates endothelial cell migration through calcium influx via T-type calcium channel in human umbilical vein endothelial cells.

AIM: The T-type calcium channel is expressed in vascular endothelial cells, but its role in endothelial cell function is yet to be elucidated. We analysed the endothelial functional role of T-type calcium channel-dependent calcium under angiotensin II (Ang II) stimulation. METHODS: Human umbilical vein endothelial cells were co-incubated with hormone at 10(-7) m and either Efonidipine 10(-5) m or Verapamil 10(-5) m or Mibefradil 10(-5) m or Wortmannin 10(-6) m. The contribution of Ang II receptors was evaluated using PD123319 10(-7) m and ZD 7155 10(-7) m. The calcium ion concentration was observed using Fluo-3 acetossimetil ester. The cells were observed after 3, 6, 9 and 12 h. RESULTS: The microfluorescence method points out that Ang II induces intracellular calcium modulation in time by distinct mechanisms. AT2 receptor blockade is necessary to observe significant increase in [Ca(2+)](i) levels. Pre-treatment with Mibefradil abolishes Ang II -induced cell migration. CONCLUSIONS: Our data show that Ang II, via AT1 receptor, modulates calcium concentration involving T-type calcium channel and L-type calcium channel but only the calcium influx via T-type calcium channels regulates endothelial cell migration which is essential for angiogenesis.

Effect of a low molecular weight peptide bound to liver mitochondrial DNA on in vitro DNA duplication.

Authors tested "in vitro" action of a low molecular weight peptide fraction extracted by mitochondrial DNA from calf liver. The fraction acts upon duplication performed by E. Coli DNA polymerase I on poli dAT dAT template inhibiting chain elongation. The authors hypothesize that a similar role is exerted by this fraction "in vitro" on mitochondrial DNA template.

Amino acid composition of two peptides purified from mitochondrial calf liver DNA.

In this research the amino acidic composition of a peptide fraction from mitochondrial DNA has been determined, using HPLC and the fingerprinting technique. This peptide fraction has been shown to be composed of two sub-fractions with different reactivity to ninhydrin, and thus supplied with several N-substitute groups. The composition of the first fraction is Gln, Glu, Pro, Leu. The second fraction composition is Pro, Glu or Gln, Asp or Asn, Ser.

Effects of a peptide fraction isolated from mitochondrial DNA on stationary rat hepatocyte culture.

In this research we have investigated the effects of mitochondrial peptide fraction bound to DNA on stationary rat hepatocyte cultures. The treatment with this peptide was responsible of cellular lysis, followed by significant proliferation after 46th day until 51st in which it is reestablished. In the present study it seems that peptides bound to hepatocyte mitochondrial DNA are involved in longer term cultural stabilization properties. Our results demonstrate that the peptide is a lysing factor activity at short terms.