The impact of Sambucus nigra L. extract on inflammation, oxidative stress and tissue remodeling in a rat model of lipopolysaccharide-induced subacute rhinosinusitis.

Rhinosinusitis is a common disorder related to inflammation of paranasal sinuses and nasal cavity mucosa. Herbal medicines could be an option in the treatment of rhinosinusitis due to their anti-inflammatory and anti-oxidative properties. The study aims to investigate the effect of intranasal Sambucus nigra L. subsp. nigra (SN) extract against inflammation, oxidative stress, and tissue remodeling in nasal and sinus mucosa, but also in serum, lungs, and brain, in Wistar rat model of subacute sinonasal inflammation induced by local administration of lipopolysaccharides (LPS), from Escherichia Coli. The cytokines (TNF-α, IL-1ß, IL-6) and oxidative stress (malondialdehyde) in nasal mucosa, blood, lungs, and brain were analyzed. In addition, a histopathological examination was performed, and NF-kB, MMP2, MMP9, TIMP1 expressions were also evaluated in nasal mucosa. Both doses of LPS increased the production of cytokines in all the investigated tissues, especially in the nasal mucosa and blood (p < 0.01 and p < 0.05), and stimulated their secretion in the lungs, and partially in the brain. Malondialdehyde increased in all the investigated tissues (p < 0.01 and p < 0.05). In parallel, upregulation of NF-kB and MMP2 expressions with downregulation of TIMP1, particularly at high dose of LPS, was observed. SN extract reduced the local inflammatory response, maintained low levels of IL-6, TNF-α, and IL-1ß. In lungs, SN reduced all cytokines levels while in the brain, the protective effect was noticed only on IL-6. Additionally, SN diminished lipid peroxidation and downregulated NF-kB in animals exposed to a low dose of LPS, with increased TIMP1 expression, while in animals treated with a high dose of LPS, SN increased NF-kB, MMP2, and MMP9 levels. In conclusion, SN extract diminished the inflammatory response, reduced generation of reactive oxygen species (ROS) and, influenced MMPs expressions, suggesting the benficial effect of SN extract on tissue remodeling in subacute rhinosinusitis and on systemic inflammatory response.

Gold nanoparticles phytoreduced with Cornus mas extract mitigate some of gliadin effects on Caco-2 cells.

Celiac disease (CD) is an autoimmune condition that occurs in genetically predisposed people where the ingestion of gluten produces damage in the small intestine. The treatment accepted until now is a strict gluten free diet. This implies the need for novel or adjuvant treatments, in addition to the standard of care. The present study aimed to assess the effect of gold nanoparticles phytosynthesized with Cornus mas extract (AuCM) compared to Cornus mas extract (CM) and luteolin (LT) on Caco-2 cells, exposed or not to gliadin. Ultraviolet-visible spectroscopy and transmission electron microscopy were used for the characterization of AuCM. Measured cellular outcomes included oxidative stress markers (malondialdehyde level, catalase and superoxide dismutase activities), inflammatory response and cellular signaling and transcription factors involved in apoptosis (NFκB, pNFκB, NOS2, TNF-α, TRAIL, Bax, Bcl-2, p53). The internalization of gold nanoparticles in cells was evidenced by transmission electron microscopy (TEM). The gliadin administration induced oxidative stress, improved the activity of antioxidants enzymes, increased NOS2 and NFκB expressions and reduced pNFκB/NFκB ratio. In addition, gliadin enhanced TRAIL and Bcl-2 levels and reduced p53 expression in Caco-2 cells. The pretreatment with AuCM, CM extract and LT diminished oxidative stress and reduced NOS2 activity. AuCM and CM treatment amplified the expression of p53 and pNFκB/NFκB ratio and diminished Bcl-2, NFκB and pNFκB, especially AuCM. The results obtained confirmed that AuCM mitigate some of gliadin effects on Caco-2 cells through modulation of oxidative stress and inflammation.

Daily oral administration of chlorogenic acid prevents the experimental carrageenan-induced oxidative stress.

Inflammation and oxidative stress are interrelated processes, during which many pathological processes lead to the reactive oxygen species (ROS) and the cytokines release. The aim of this experimental study was to analyse the effects of chlorogenic acid, in oral daily administration, against the oxidative stress and oedema development in experimental carrageenan-induced rat paw inflammation. The oxidative stress parameters were investigated after a paw inflammation was produced in rats that previoulsy received, for 14 days, either chlorogenic acid (100 mg/day or 150 mg/day) or indomethacin (1 mg/kg/day). The paw oedema was measured through plethysmometry made at 2, 6 and 24 hours after carrageenan injection. The oxidative stress was investigated through spectrophotometry. Blood samples, paw skin and kidneys were collected to investigate malondialdehyde (MDA), glutathione (GSH) and oxidized glutathione (GSSG). The protein expression of oxidative stress-related pathways was analysed in skin and kidneys through Western blot. The present study showed that indomethacin and both doses of chlorogenic acid, after 14 days of oral administration, exerted antioedematous effects during the inflammation development after carrageenan local injection. Compared to the group that received only carrageenan injection, significant decreases of the inflamed paw volume were shown in the treated groups (P < 0.001), in all inflammation phases. The lipid peroxidation was significantly decreased by both doses of chlorogenic acid in inflamed skin (P < 0.0001) and kidney (P < 0.0001). In serum, it was significantly inhibited by indomethacin (P < 0.01) and by 100 mg/day of chlorogenic acid (P < 0.05). The antioxidant protection, evaluated through the ratio GSH/GSSG, was significantly increased by chlorogenic acid in inflamed skin (P < 0.0001) and kidney (100 mg/day, P < 0.01; 150 mg/day, P < 0.0001). In serum, only indomethacin administration produced significant increases of the antioxidant protection (P < 0.05). Western blot analysis showed significant decreases of COX-2 in inflamed skin and kidney in the groups of rats that received indomethacin or 100 mg/day of chlorogenic acid. The effects of chlorogenic acid on NF-κB and pNF-κB were dose-dependent.

The effect of Tropaeolum majus L. on bacterial infections and in vitro efficacy on apoptosis and DNA lesions in hyperosmotic stress.

Tropaeolum majus L. (T. majus) or nasturtium is a medicinal plant widespread in the areas with temperate climate, commonly used in culinary and in traditional medicine due to therapeutic properties. In the last few years, various effects of the flowers and leaves of this plant have been studied, but their benefits are not fully known. The aim of the study was to identify the phenolic compounds from T. majus edible flowers in relation with its antioxidant capacity and the antimicrobial activity against different bacteria and Candida albicans. In addition, the impact of natural extract on oxidative stress, inflammation and apoptosis was analysed on human umbilical vein endothelial cells (HUVECs) exposed to normotonic and hypertonic conditions. The major phenolic acids, identified by HPLC-RP with UV detection, were gallic acid, caffeic acid and p-coumaric and predominant flavonoids were quercetin, epicatechin and luteolin. The both fractions of T. majus were rich sources of polyphenols with marked antioxidant activity, evidenced by TEAC or DPPH methods. The extract exhibited a week antibacterial effect on some strains of streptococcus, without antifungal or antibacterial effect on gram negative bacteria. T. majus extract increased the p53 and Bcl-2 expressions and diminished the DNA lesions indicating the protective and antiapoptotic effects in vitro, on endothelial cells exposed to hyperosmotic stress. These experimental findings suggest that T. majus can exert some protection against bacterial infections and reduce apoptosis and DNA lesions in hypertonic conditions.

Characterization and biological effects of Hypericum extracts on experimentally-induced - anxiety, oxidative stress and inflammation in rats.

Anxiety disorders can associate with oxidative stress and immune system alterations. Our study aimed to chemically analyze Hypericum maculatum (HM) and Hypericum perforatum (HP) dry extracts and to evaluate their effects along with quercetin (Q), on brain oxidative stress biomarkers: malondialdehyde (MDA), catalase (CAT) and superoxide dismutase (SOD), inflammatory cytokines: interleukin-1α, (IL-1α), IL-1ß, regulated on activation normal T cell expressed and secreted (RANTES), interferon (IFN), monocyte chemoattractant protein-1 (MCP1), macrophage inflammatory protein (MIP) and serum corticosterone levels. Nuclear transcription factor κB (NFκB) signaling pathway in the hippocampus and frontal lobe in rats with N-methyl-9H-pyrido[5,4-b]indole-3-carboxamide (FG-7142) experimental-induced anxiety were also investigated. The chemical analyses of total hypericins were performed by spectrophotometric analysis and hypericin, hyperforin and polyphenols derivatives were quantified by chromatographic methods. The animals were divided in 6 groups: carboxymethylcellulose 2% (CMC); CMC + FG; alprazolam (APZ) + FG; Q + FG; HM + FG; HP + FG. APZ (0.08 mg/kg b.w.), Q (30 mg/kg b.w.), HM and HP (350 mg/kg b.w.) were orally administered for 21 days. FG (7.5 mg/kg b.w.) was intraperitoneally (i.p.) injected in a single dose. Q and hypericum extracts (HpE) exerted anti-inflammatory (decreased IL-1α, IL-1ß, MCP1, IFN and MIP mainly in hippocampus) and antioxidant effects (decreased MDA levels, increased CAT and SOD activity), enhanced NFκB and pNFκB expressions in the brain and reduced serum corticosterone levels. Our findings suggest that HpE may improve anxiety-like behavior, offer brain protection by modulation of oxidative stress and inflammation, and can contribute to overall biological activity of natural compounds-rich diet.

In vitro studies on the mechanisms involved in chemoprevention using Calluna vulgaris on vascular endothelial cells exposed to UVB.

The study aims to investigate the mechanisms involved in the in vitro effect of UVB on endothelial vascular cells (HUVECs) pretreated with a photochemopreventive agent, the Calluna vulgaris (Cv) extract. Two concentrations of Cv, below the limit of cytotoxicity IC50 (2.5 and 7.5 µg GAE/ml) and two doses of UVB (50 and 100 mJ/cm(2)) were used. Oxidative stress parameters were quantified at 1 h and 24 h after irradiation and apoptosis, DNA damage and the induction/activation of NF-κB were evaluated at 24 h. UVB exposure led to the formation of lipid peroxides in a dose dependent manner (p<0.001), induced apoptosis, increased the γ-H2AX levels and the activation of NF-κB. Pretreatment with 2.5 µg GAE/ml Cv improved the antioxidant defense, protected against DNA lesions and was able to decrease cellular death at low dose of irradiation. 7.5 µg GAE/ml Cv was prooxidant, favored the formation of DNA lesions, amplified the NF-κB activation UVB-induced (p<0.01) and led to high levels of cellular death. Both doses of Cv inhibited caspase-3 activation. The modulatory effect of Cv extract on endothelial cells exposed to UVB depend on the concentration of Cv used. This study provides insides into the mechanisms triggered by UVB and antioxidants on skin endothelial cells.

Photodynamic therapy in melanoma--an update.

Melanoma, a cancer that arises from melanocytes is one of the most unresponsive cancers to known therapies. Several studies showed encouraging results of the efficacy of photodynamic therapy (PDT) using different experimental settings in vitro and in vivo as well as a few clinical reports, suggesting a possible role as an adjuvant therapy in the management of advanced melanoma (stage III and IV). In experimental settings, PDT using different protocols on human and mice melanoma cells induced significant apoptosis, necrosis, tumor growth arrest and prolonged the survival of the animals, but seldom achieved complete remission and/or was followed by recurrence and side effects. Clinical reports showed regression of choroidal melanoma and skin melanoma metastasis following PDT. PDT consists in administration of a photosensitizer, which undergoes excitation after suitable irradiation emitted from a light source and generates singlet oxygen (¹O2) and other cytotoxic oxygen species such as superoxide anion radical (O2·â») and hydroxyl radical (OH·). The antitumor effects result from the combination of direct tumor cell photodamage, destruction of tumor vasculature and activation of an immune response. To increase the effectiveness of PDT in melanoma, the therapy has to overcome the protective mechanisms like pigmentation and increased oxidative stress defense, possibly through inhibition of melanogenesis and melanosome targeted photosensitizers. The optimal protocols for tumor and vascular targeted PDT could destroy melanoma and endothelial tumor cells and activate the immune response, thus increasing the overall efficacy. Combination of PDT with immune stimulation therapies might increase the efficiency in destroying the initial tumor as well as micro metastases and decrease the melanoma relapses.

Chemopreventive effects of Calluna vulgaris and Vitis vinifera extracts on UVB-induced skin damage in SKH-1 hairless mice.

Solar ultraviolet radiation (UV) is a major cause of non-melanoma skin cancer in humans. Photochemoprevention with natural products represents a simple but very effective strategy in the management of cutaneous neoplasia. The study investigated the protective activity of Calluna vulgaris (Cv) and red grape seeds (Vitis vinifera L, Burgund Mare variety) (BM) extracts in vivo on UVB-induced deleterious effects in SKH-1 mice skin. Forty SKH-1 mice were randomly divided into 4 groups (n=10): control, UVB irradiated, Cv + UVB irradiated, BM+UVB irradiated. Both extracts were applied topically on the skin in a dose of 4 mg/40 µl/cm(2) before UVB exposure - single dose. The effects were evaluated in skin 24 hours after irradiation through the presence of cyclobutane pyrimidine dimers (CPDs) and sunburn cells, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 levels. The antioxidant activity of BM extract was higher than those of Cv extract as determined using stable free radical DPPH assay and ABTS test. One single dose of UVB generated formation of CPDs (p<0.0001) and sunburn cells (p<0.0002) and increased the cytokine levels in skin (p<0.0001). Twenty hours following irradiation BM extract inhibited UVB-induced sunburn cells (p<0.02) and CPDs formation (p<0.0001). Pretreatment with Cv and BM extracts resulted in significantly reduced levels of IL-6 and TNF-α compared with UVB alone (p<0.0001). Our results suggest that BM extracts might be a potential candidate in preventing the damages induced by UV in skin.

Pharmacokinetic interaction between ivabradine and carbamazepine in healthy volunteers.

WHAT IS KNOWN AND OBJECTIVE: Ivabradine is a novel heart rate-lowering agent that selectively and specifically inhibits the depolarizing cardiac pacemaker If current in the sinus node. Our objective was to evaluate a possible pharmacokinetic interaction between ivabradine and carbamazepine in healthy volunteers. METHODS: The study consisted of two periods: Period 1 (Reference), when each volunteer received a single dose of 10 mg ivabradine and Period 2 (Test), when each volunteer received a single dose of 10 mg ivabradine and 400 mg carbamazepine. Between the two periods, the subjects were treated for 15 days with a single daily dose of 400 mg carbamazepine. Plasma concentrations of ivabradine were determined during a 12-h period following drug administration, using a high-throughput liquid chromatography with mass spectrometry analytical method. Pharmacokinetic parameters of ivabradine administered in each treatment period were calculated using non-compartmental and compartmental analysis to determine if there were statistically significant differences. RESULTS AND DISCUSSION: In the two periods of treatments, the mean peak plasma concentrations (C(max)) were 16·25 ng/mL (ivabradine alone) and 3·69 ng/mL (ivabradine after pretreatment with carbamazepine). The time taken to reach C(max), t(max), were 0·97 and 1·14 h, respectively, and the total areas under the curve (AUC(0-∞)) were 52·49 and 10·33 ng h/mL, respectively. These differences were statistically significant for C(max) and AUC(0-∞) when ivabradine was administered with carbamazepine, whereas they were not for t(max), half-life and mean residence time. WHAT IS NEW AND CONCLUSION: T Carbamazepine interacts with ivabradine in healthy volunteers, and lowers its bioavailability by about 80%. This magnitude of effect is likely to be clinically significant.

The role of ultraviolet radiation and tyrosine stimulated melanogenesis in the induction of oxidative stress alterations in fair skin melanocytes.

BACKGROUND: Melanocytes are producing melanin after UV irradiation as a defense mechanism. However, UV-induced damage is involved in melanoma initiation, depending on skin phototype. Melanocytes seem to be extremely susceptible to free radicals. Their main enzymatic antioxidants are superoxide dismutase and catalase. AIM: To study how melanin synthesis modulates the activity of the oxidative stress defense enzymes and cell proliferation after UV induced cell damage. METHODS: Normal human melanocyte cultures from fair skin individuals were exposed to high levels of L-tyrosine and irradiated, with 20, 30, 40 mJ/cm2 UVA, and respective UVB. Proliferation was measured using a MTS assay; viability was assessed by trypan blue exclusion dye method. Spectrophotometrical methods were used to determine total melanin content, the enzymatic activity of tyrosinase, superoxide dismutase and catalase. RESULTS: Tyrosine had a negative effect on proliferation, enhanced with time elapsed. Overall, UV irradiation decreased proliferation. UVA increased proliferation relative to UVB in the cultures exposed for a longer time to high (2 mM) tyrosine concentration. There were no proliferation differences between UVA and UVB irradiation in lower tyrosine concentration exposed melanocytes. Both, UV irradiation and tyrosine increased melanogenesis. Exposure of the melanocytes to increased levels of tyrosine in medium (0.5 mM and 1 mM) and UV irradiation enhanced the activity of superoxide dismutase and catalase. The enzymes showed a high activity rate in melanocytes while exposed for a short time to 2 mM tyrosine, but their activity was dramatically decreased with longer tyrosine exposure and UV irradiation. CONCLUSION: Our data indicate that in low phototype melanocytes, melanogenesis, either following UV irradiation, or tyrosine exposure, especially in high concentrations, was detrimental for the cells by reducing the activity of catalase and superoxidedismutase, the natural antioxidants. UVA was more efficient in stimulating the activity of superoxide dismutase and catalase but also in depleting the reserves of the enzymatic defense against oxidative stress, especially catalase, than UVB. This physiologic response to UV light can be considered as an adjunctive risk factor for people with low phototype for developing a melanoma, when exposed to UV irradiation.

Potential application of the reaction between hydroquinone and chromate with respect to the kinetic determination of iron.

The analytical potential of the reaction between hydroquinone and chromate in acidic media is explored with respect to the kinetic determination of iron in water samples. The extent of the reaction is followed spectrophotometrically at 350 nm. The reaction occurs more quickly in the presence of the metal ion, but the values of absorbance at reaction initiation and completion are not altered. No other transitional metal ion affects the course of the reaction, regardless of its concentration. This fact represents the most eye-catching and analytically exploitable aspect of this indicator reaction. Three procedures used to obtain calibration graphs from the same kinetic data are discussed: slope, fixed and variable time techniques. The reaction follows a sequence of two consecutive steps, both of first-order with respect to the colored species. First-order kinetics is preserved in the presence of iron. Curve fitting is used to determine the corresponding rate coefficients. The slope method requires much data and uses plots of rate constants against analyte concentration for calibration purposes. In this case, the best detection limit (0.5 mg l(-1)) is given by the faster stage. On the other hand, the rate-determining step enables more precise results. The fixed and variable time methods rely on similar principles: they register either the value of absorbance achieved at a predetermined reaction time (here, 50 s) or the time interval required for the absorbance to drop to a predetermined value (here, 0.15 absorbance at 350 nm). In both cases, ratios between the average value from the blind runs and all individual values are plotted against the analyte concentration. The best results (detection limit of 0.3 mg l(-1)) are derived from the variable time procedure. Advantageously, neither of the techniques require the entire kinetic curve, and so sophisticated equipment is not needed.

Kinetic catalytic determination of trace Cu(II) in water samples with the thioglycolic/thiolactic acid-chromate reaction.

The use of two novel similar indicator reactions as applied to the kinetic determination of Cu(II) in water is investigated. The methods rely on the catalytic effect of the analyte on the oxidation of thioglycolic (TGA) and thiolactic (TLA) acids by chromate in acidic media. The extent of the reactions was followed spectrophotometrically at 345 nm. Pseudo-first-order rate coefficients, k(obsd), were determined as a function of catalyst concentration. Interference of Fe(III) and Pb(II) was suppressed by complexation with pyrophosphate. For the reaction of TGA, a linear regression for k(obsd) versus [Cu(II)] was obtained for the entire concentration range considered. Although the plot corresponding to TLA oxidation exhibits a sharp change of slope at approximately 1.8x10(-5) M Cu(II), it can still be described effectively by two linear regressions with different slopes. The reaction of TGA is more sensitive than that of TLA at low Cu(II) concentration. The opposite is true for higher catalyst contents. The detection limits were 65 microg L(-1) for TGA and of 80 microg L(-1) for TLA oxidation, respectively. The relative standard deviations, of 0.4% for TGA and 1.1% for TLA oxidation, respectively, were obtained for five replicate runs at 1000 microg L(-1). Samples of river and wastewater from the mining region of Baia-Mare, Northern Romania were analyzed using the more sensitive reaction of thioglycolic acid. Results were compared to those obtained by the officially standardized methods. Good agreement was obtained, even for an untreated sample. Measurements did not require prior separation of interfering species.