The Impact of Some Modulators of the Renin-Angiotensin System on the Scopolamine-Induced Memory Loss Mice Model.

As some of the renin-angiotensin-aldosterone system (RAAS)-dependent mechanisms underlying the cognitive performance modulation could include oxidative balance alterations, in this study we aimed to describe some of the potential interactions between RAAS modulators (Losartan and Ramipril) and oxidative stress in a typical model of memory impairment. In this study, 48 white male Swiss mice were divided into six groups and received RAAS modulators (oral administration Ramipril 4 mg/kg, Losartan 20 mg/kg) and a muscarinic receptors inhibitor (intraperitoneal injection scopolamine, 0.5 mg/kg) for 8 consecutive days. Then, 24 h after the last administration, the animals were euthanized and whole blood and brain tissues were collected. Biological samples were then processed, and biochemical analysis was carried out to assess superoxide dismutase and glutathione activities and malondialdehyde concentrations. In the present experimental conditions, we showed that RAAS modulation via the angiotensin-converting enzyme inhibition (Ramipril) and via the angiotensin II receptor blockage (Losartan) chronic treatments could lead to oxidative stress modulation in a non-selective muscarinic receptors blocker (scopolamine) animal model. Our results showed that Losartan could exhibit a significant systemic antioxidant potential partly preventing the negative oxidative effects of scopolamine and a brain antioxidant potential, mainly by inhibiting the oxidative-stress-mediated cellular damage and apoptosis. Ramipril could also minimize the oxidative-mediated damage to the lipid components of brain tissue resulting from scopolamine administration. Both blood serum and brain changes in oxidative stress status were observed following 8-day treatments with Ramipril, Losartan, scopolamine, and combinations. While the serum oxidative stress modulation observed in this study could suggest the potential effect of RAAS modulation and scopolamine administration on the circulatory system, blood vessels endothelia, and arterial tension modulation, the observed brain tissues oxidative stress modulation could lead to important information on the complex interaction between renin-angiotensin and cholinergic systems.

Oxidative stress markers dynamics in keratoconus patients' tears before and after corneal collagen crosslinking procedure.

Keratoconus (KC) is a controversial ophthalmological disease, often considered both multifactorial and multigenic with poor or not entirely understood etiopathogenesis. Corneal collagen crosslinking (CXL) procedure is the most common surgical therapy for KC which both slows corneal thinning and halts disease progression. While extensive studies provide consistent evidence on systemic oxidative stress in KC patients and animal models, little is known on the tear fluid oxidative stress markers such as antioxidant enzymes activity or lipid peroxidation markers. Also, little is known considering the oxidative status dynamics following CXL. In this way, we aimed to evaluate three oxidative stress markers in the tears of KC patients before and after CXL procedure. Total superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymatic activity and malondiladehyde (MDA) levels were assessed from the tears of 20 kC patients who received the recommendation for CXL procedure. Significantly decreased SOD activity (p = 0.0014) was observed in KC patients tears, as compared to age and sex-matched controls which could lead to significant lipid peroxidation boost (p < 0.001). Significantly higher GPx enzyme activity was observed in KC patients, as compared to control (p < 0.001), suggesting a compensatory response to intense lipid peroxidation. Following CXL, SOD activity significantly decreases and GPx activity extensively increases, as compared to baseline KC levels and controls (p < 0.001). This work provides additional evidence on oxidative stress status in the tears of KC considering general oxidative stress markers dynamics both before and after the CXL procedure. We also demonstrated that the CXL procedure could have further relevance in the management of this disorder.

Preliminary Biochemical Description of Brain Oxidative Stress Status in Irritable Bowel Syndrome Contention-Stress Rat Model.

Background and objectives: Oxidative stress and inflammation have been implicated in the etiology of irritable bowel syndrome (IBS), a common gastrointestinal functional disease. This study aimed to further characterize the contention-stress rat model by exploring a possible correlation between oxidative stress markers measured in brain tissues with behavioral components of the aforementioned model. Thus, it is hereby proposed a possible IBS animal model relevant to pharmacological and complementary medicine studies. Materials and Methods: Wild-type male Wistar rats (n = 5/group) were chronically exposed to 6-hour/day contention, consisting of isolating the animals in small, vital space-granting plastic devices, for seven consecutive days. Following contention exposure, temporal lobes were extracted and subjected to biochemical analyses to assess oxidative stress-status parameters. Results: Our results show increased brain oxidative stress in contention-stress rat model: decreased superoxide dismutase and glutathione peroxidase activities and increased malondialdehyde production in the IBS group, as compared to the control group. Furthermore, the biochemical ratios which are used to evaluate the effectiveness of an antioxidant system on oxidative stress could be described in this model. Conclusions: The correlations between the behavioral patterns and biochemical oxidative stress features could suggest that this may be a complex model, which can successfully mimic IBS symptomatology further providing evidence of a strong connection between the digestive system, enteric nervous system, and the central nervous system.

EFFECTS OF ZINGIBER OFFICINALE ROSCOE FRESH EXTRACT ON AMELANOTIC MELANOMA AND NORMAL SKIN FIBROBLASTS.

UNLABELLED: Zingiber officinale Roscoe is a very important medicinal plant, with a long history of therapeutic uses, especially in oriental traditional medicine. AIM: To investigate the cytotoxicity of a fresh ginger extract on some skin tumor cells compared to normal cells. MATERIAL AND METHODS: C32 amelanotic melanoma cell line and CCD human skin fibroblasts were used. The fresh extract obtained by crushing ginger rhizome was examined for phenolic content. The in vitro cytotoxicity was examined using phase contrast microscopy and MTT assay for the concentrations of 2 and 4 mg% total phenols. RESULTS: Both concentrations used for treatment induced no changes in normal the morphology and viability of fibroblasts compared to control cells. Amelanotic melanoma cells displayed profound changes in cell morphology such as cell shrinkage, rounding-up and membrane blebbing and a decrease in cell viability in a dose-dependent manner. CONCLUSIONS: Fresh ginger extract induced no changes in normal skin fibroblast viability, but caused profound cytotoxic effects on amelanotic melanoma. These results could encourage further studies regarding the intimate mechanisms of the antitumor action displayed by the fresh ginger extract.

PINUS cembra L: histo-anatomical features, antioxidant enzyme activities and heavy metal contents of leaves and long shoots.

AIM: This study aimed to investigate the histo-anatomical features of the long shoots and leaves (young and mature) of Pinus cembra L.. The activity of antioxidant enzymatic systems and the content of heavy metals were also evaluated. MATERIAL AND METHODS: For the histo-anatomical study, the cross-sections were performed by usual techniques. The activity of antioxidant enzymatic systems (superoxide dismutase, catalase and peroxidase) was evaluated by spectrophotometric methods. The content of heavy metals was determined by atomic absorption spectroscopy. RESULTS: The cross-section through the long shoots shows many resiniferous canals and a periderm of variable thickness. The leaf has a triangular shape and only two vascular bundles in the inferior and upper levels. The highest level of superoxide dismutase activity (344.90 U/mg protein) was determined in the long shoots collected from a cembran pine in Vatra Dornei, while the highest level of peroxidase activity (7611.11 U/mg protein) was found in the leaves collected in Calimani Mountains. Cd level in all samples was under the quantification limit. Higher levels of Pb were determined in the long shoots (3 µg/g dry weight for the vegetal material collected in Vatra Dornei and 2.86 µg/g dry weight for the vegetal material collected in Calimani Mountains). CONCLUSIONS: Pinus cembra L. leaves show specific elements of subgenus Strobus (a triangular shape of the cross section, one single vascular bundle and two resiniferous canals). The results obtained for the superoxide dismutase and peroxidase activities corroborated with those obtained for the heavy metal contents indicate that antioxidant enzymes play an important role in the protection of Pinus cembra L. against exogenous stress factors.