The impact of chronic Trimethylamine N-oxide administration on liver oxidative stress, inflammation, and fibrosis

TMAO, a gut microbiota derived byproduct, has been associated with various cardiometabolic diseases by promoting oxidative stress and inflammation. The liver is the main organ for TMAO production and chronic exposure to high doses of TMAO could alter its function. In this study, we evaluated the effect of chronic exposure of high TMAO doses on liver oxidative stress, inflammation, and fibrosis. TMAO was administered daily via gastric gavage to laboratory rats for 3 months. Blood was drawn for the quantification of TMAO, and liver tissues were harvested for the assessment of oxidative stress (MDA, GSH, GSSG, GPx, CAT, and 8-oxo-dG) and inflammation by quantification of IL-1α, TNF-α, IL-10, TGF-β, NOS and COX-2 expression. The evaluation of fibrosis was made by Western blot analysis of α-SMA and Collagen-3 protein expression. Histological investigation and immunohistochemical staining of iNOS were performed in order to assess the liver damage. After 3 months of TMAO exposure, TMAO serum levels enhanced in parallel with increases in MDA and GSSG levels in liver tissue and lower values of GSH and GSH/GSSG ratio as well as a decrease in GPx and CAT activities. Inflammation was also highlighted, with enhanced iNOS, COX-2, and IL-10 expression, without structural changes and without induction of liver fibrosis.

Investigation of Epilobium hirsutum L. Optimized Extract's Anti-Inflammatory and Antitumor Potential

Epilobium hirsutum L., commonly known as hairy willowherb, is a perennial herbaceous plant native to Europe and Asia. In Romania, the Epilobium genus includes 17 species that are used in folk medicine for various purposes. This study aimed to investigate the anti-inflammatory and antitumor potential of the optimized extract of Epilobium hirsutum (EH) in animal models. The first study investigated the anti-inflammatory properties of EH optimized extract and the model used was carrageenan-induced paw inflammation. Wistar rats were divided into three groups: negative control, positive control treated with indomethacin, and a group treated with the extract. Oxidative stress markers, cytokine levels, and protein expressions were assessed. The extract demonstrated anti-inflammatory properties comparable to those of the control group. In the second study, the antitumor effects of the extract were assessed using the tumor model of Ehrlich ascites carcinoma. Swiss albino mice with Ehrlich ascites were divided into four groups: negative, positive treated with cyclophosphamide (Cph), Group 3 treated with Cph and EH optimized extract, and Group 4 treated with extract alone. Samples from the ascites fluid, liver, and heart were analyzed to evaluate oxidative stress, inflammation, and cancer markers. The extract showed a reduction in tumor-associated inflammation and oxidative stress. Overall, the EH optimized extract exhibited promising anti-inflammatory and antitumor effects in the animal models studied. These findings suggest its potential as a natural adjuvant therapeutic agent for addressing inflammation and oxidative stress induced by different pathologies.

Hybrid Material Based on Vaccinium myrtillus L. Extract and Gold Nanoparticles Reduces Oxidative Stress and Inflammation in Hepatic Stellate Cells Exposed to TGF-β

(1) Background: The study aimed to investigate the impact of gold nanoparticles capped with Cornus sanguinea (NPCS) and mixed with a fruit extract (Vaccinum myrtillus L.-VL) on human hepatic stellate cells (LX-2) exposed to TGF-β. (2) Methods: NPCS were characterized by UV-Vis, transmission electron microscopy (TEM), zeta potential measurement, X-ray diffraction (XRD) and energy dispersive spectroscopy (EDX). The cytotoxic effects of VL, NPCS and of the hybrid compounds obtained by mixing the two components in variable proportions (NPCS-VL) were assessed. LDH activity, MDA levels, secretion of inflammation markers, the expression of fibrogenesis markers and collagen I synthesis were estimated after treating the cells with a mixture of 25:25 μg/mL NPCS and VL. (3) Results: TEM analysis showed that NPCS had spherical morphology and homogenous distribution, while their formation and elemental composition were confirmed by XRD and EDX analysis. TGF-β increased cell membrane damage as well as secretion of IL-1β, IL-1α and TLR4. It also amplified the expression of α-SMA and type III collagen and induced collagen I deposition. NPCS administration reduced the inflammation caused by TGF-β and downregulated α-SMA expression. VL diminished LDH activity and the secretion of proinflammatory cytokines. The NPCS-VL mixture maintained IL-1β, IL-1α, TLR4 and LDH at low levels after TGF-β exposure, but it enhanced collagen III expression. (4) Conclusions: The mixture of NPCS and VL improved cell membrane damage and inflammation triggered by TGF-β and mitigated collagen I deposition, but it increased the expression of collagen III, suggestive of a fibrogenetic effect of the hybrid material.

An In Vitro and In Vivo Assessment of Antitumor Activity of Extracts Derived from Three Well-Known Plant Species

One of the objectives of this study consists of the assessment of the antitumor activity of several extracts from three selected plant species: Xanthium spinosum L., Trifolium pratense L., and Coffea arabica L. and also a comparative study of this biological activity, with the aim of establishing a superior herbal extract for antitumor benefits. The phytochemical profile of the extracts was established by HPLC-MS analysis. Further, the selected extracts were screened in vitro for their antitumor activity and antioxidant potential on two cancer cell lines: A549-human lung adenocarcinoma and T47D-KBluc-human breast carcinoma and on normal cells. One extract per plant was selected for in vivo assessment of antitumor activity in an Ehrlich ascites mouse model. The extracts presented high content of antitumor compounds such as caffeoylquinic acids in the case of X. spinosum L. (7.22 µg/mL-xanthatin, 4.611 µg/mL-4-O-caffeoylquinic acid) and green coffee beans (10.008 µg/mL-cafestol, 265.507 µg/mL-4-O-caffeoylquinic acid), as well as isoflavones in the case of T. pratense L. (6806.60 ng/mL-ononin, 102.78 µg/mL-biochanin A). Concerning the in vitro results, the X. spinosum L. extracts presented the strongest anticancerous and antioxidant effects. In vivo, ascites cell viability decreased after T. pratense L. and green coffee bean extracts administration, whereas the oxidative stress reduction potential was important in tumor samples after T. pratense L. Cell viability was also decreased after administration of cyclophosphamide associated with X. spinosum L. and T. pratense L. extracts, respectively. These results suggested that T. pratense L. or X. spinosum L. extracts in combination with chemotherapy can induce lipid peroxidation in tumor cells and decrease the tumor viability especially, T. pratense L. extract.

The Acute Effect of Trimethylamine-N-Oxide on Vascular Function, Oxidative Stress, and Inflammation in Rat Aortic Rings

A growing body of evidence suggests that the gut microbiota affects the cardiovascular system directly and indirectly via biologically active molecules. TMAO, a key metabolite produced by gut bacteria is implicated in atherosclerosis and chronic endothelial dysfunction, but with an unclear effect on vascular tone, oxidative stress, and inflammation. Our study aimed to evaluate the acute effects of TMAO on vascular contractility in relation with oxidative stress markers and inflammation. Aortic rings were harvested from laboratory rats and placed in a tissue bath system containing TMAO in concentrations of 300, 100, 10 µM, and control. Vascular tone under the influence of vasoconstrictor phenylephrine and non-endothelial-dependent vasodilator sodium nitroprusside was assessed using force transducers connected to a computer-based acquisition system. Oxidative stress and inflammation were quantified by vascular assessment of the activity of NF-κB, NRF2, SOD1, and iNOS by western-blotting and MDA by spectrofluorimetry. After the incubation of the aortic rings in TMAO solutions for 1 h, there was no difference in vasoconstrictor and non-endothelial vasodilator response between the studied doses. TMAO acutely induced oxidative stress and inflammation, significantly increasing levels of MDA and the expression of NF-κB, NRF2, SOD1, and iNOS, mostly in a dose-dependent manner. Our study showed the lack of a short-term effect of studied TMAO doses on vascular contractility, but demonstrated an acute prooxidative effect and activation of major inflammatory pathways, which can partially explain the detrimental effects of TMAO in cardiovascular disease.

Iron chelation alleviates multiple pathophysiological pathways in a rat model of cardiac pressure overload

Iron dysmetabolism affects a great proportion of heart failure patients, while chronic hypertension is one of the most common risk factors for heart failure and death in industrialized countries. Serum data from reduced ejection fraction heart failure patients show a relative or absolute iron deficiency, whereas cellular myocardial analyses field equivocal data. An observed increase in organellar iron deposits was incriminated to cause reactive oxygen species formation, lipid peroxidation, and cell death. Therefore, we studied the effects of iron chelation on a rat model of cardiac hypertrophy. Suprarenal abdominal aortic constriction was achieved surgically, with a period of nine weeks to accommodate the development of chronic pressure overload. Next, deferiprone (100 mg/kg/day), a lipid-permeable iron chelator, was administered for two weeks. Pressure overload resulted in increased inflammation, fibrotic remodeling, lipid peroxidation, left ventricular hypertrophy and mitochondrial iron derangements. Deferiprone reduced cardiac inflammation, lipid peroxidation, mitochondrial iron levels, and hypertrophy, without affecting circulating iron levels or ejection fraction. In conclusion, metallic molecules may pose ambivalent effects within the cardiovascular system, with beneficial effects of iron redistribution, chiefly in the mitochondria.

Chronic oral trimethylamine-N-oxide administration induces experimental incipient atherosclerosis in non-genetically modified mice

Atherosclerosis is a chronic inflammatory disease of the arterial wall involving inflammation, redox imbalance, and impaired cholesterol transport. A high level of trimethylamine-N-oxide (TMAO) produced by meat and fat metabolism are involved in atherosclerosis development, but the exact relationship with inflammation is not completely clear. The study aimed to identify a possible association between TMAO; atherosclerotic changes in the aortic root; oxidative stress; and inflammation quantified by highly sensitive C-reactive protein (hsCRP), tumor necrosis factor alpha (TNF-α), and interleukin-1beta (IL-1β) levels. TMAO dihydrate was administered via gastric gavage to 20 male Wistar rats for 90 days; one separate group received vehicle. The TMAO-treated animals were divided into two groups: one group received a low dose of TMAO (20 mg/day) and the other group received a high dose of TMAO (40 mg/day). Malondialdehyde (MDA), proinflammatory markers - IL-1β, TNF-α, and hsCRP, total cholesterol, high-density lipoprotein (HDL)-cholesterol, triglycerides, and glucose were assessed 30 and 90 days after TMAO administration. Additionally, conventional histopathology and immunohistochemistry for collagen I distribution were performed. MDA, hsCRP, TNF-α, and IL-1β levels increased after 90 days of TMAO administration in conjunction with significant changes suggestive of incipient atherosclerosis and inflammation of the aortic root. The increase was higher in the group treated with 40 mg/day TMAO compared with the group treated with 20 mg/day TMAO. Additionally, blood levels of TMAO were significantly correlated with hsCRP, TNF-α, IL-1β levels, but also with MDA, low HDL-cholesterol levels, and high triglyceride levels. The increase in MDA and inflammatory cytokines and modification of lipid metabolism markers may explain the pro-atherogenic effect of TMAO.

Effects of Gold Nanoparticles Functionalized with Bioactive Compounds from Cornus mas Fruit on Aorta Ultrastructural and Biochemical Changes in Rats on a Hyperlipid Diet-A Preliminary Study

Cornus mas L. extract (CM) presents hypolipidemic, antioxidant and anti-inflammatory activity. Gold nanoparticles (AuNPs) are considered potent delivery systems and may be used to release pharmaceutical compounds at the level of injury. In our study, we used gold nanoparticles functionalized with bioactive compounds from Cornus mas L. (AuNPsCM) in an experimental model of a high-fat diet (HFD), and we assessed their effects on aorta wall but also in the serum, as compared to Cornus mas (CM) administration. Sprague Dawley female rats were fed for 9 months with an HFD. During the last month of the experiment, we randomly allocated the animals into three groups that received, by oral gavage: saline solution, CM solution (0.158 mg/mL polyphenols) or AuNPsCM solution (260 μg Au/kg/day), while a Control group received a standard diet and saline solution. At the end of the experiment, we performed an ultrasonography of the aorta and left ventricle and a histology and transmission electron microscopy of the aorta walls; we investigated the oxidative stress and inflammation in aorta homogenates and in serum and, in addition, the lipid profile. AuNPsCM presented better effects in comparison with the natural extract (CM) on lipid peroxidation (p < 0.01) and TNF-alpha (p < 0.001) in aorta homogenates. In serum, both CM and AuNPsCM decreased the triglycerides (p < 0.001) and C-reactive protein (CM, p < 0.01; AuNPsCM, p < 0.001) and increased the antioxidant protection (p < 0.001), in comparison with the HFD group. In intima, AuNPsCM produced ultrastructural lesions, with the disorganization of intima and subendothelial connective layer, whereas CM administration preserved the intima normal aspect, but with a thinned subendothelial connective layer. AuNPsCM oral administration presented certain antioxidant, anti-inflammatory and hypolipidemic effects in an experimental model of HFD, but with a negative impact on the ultrastructure of aorta walls, highlighted by the intima disorganization.

Iron chelation effects on lipid peroxidation, inflammation and ventricular performance in a rat model of isoproterenol induced acute myocardial stress

Acute cardiac pathologies represent one of the leading causes of death, while iron metabolism is recognized to be implicated in reactive oxygen species production, lipid peroxidation, and inflammation. The aim of the present study was to assess iron chelation effects in isoproterenol (ISO) induced acute cardiac stress. We divided male Wistar rats into preventive and secondary treatment groups, with the active arm consisting in deferiprone (DFP), a lipid permeable chelator. Mortality of ISO was 10-18.18% in both preventive and secondary groups. We analyzed serum and myocardial tissue parameters of inflammation, iron dynamics, and lipid peroxidation, accompanied by ultramicroscopy, histological, and ultrasound-derived parameters of left ventricular function. Results reveal that ISO-mediated lipid peroxidation and inflammation are alleviated by administration of DFP, with negligible effect on systemic ferroregulation dynamics and global ventricular function (as assessed by ultrasound). DFP administration after cardiovascular stress is associated with a decrease in lipid peroxidation and inflammation, without an improvement in gross left ventricular parameters.

IL27 T4730C Polymorphism and Serology in Multiple Sclerosis: A Pilot Study

BACKGROUND

Multiple sclerosis (MS) is one of the most debilitating neurological diseases of young adults. The presence of a single nucleotide polymorphism in the promoter regions of the interleukin 27 gene (IL27 T4730C, rs181206) may alter the transcription and the production of cytokine levels, leading to MS.

PATIENTS AND METHODS

We performed a case-control study including 82 individuals: 51 patients diagnosed with MS and 31 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism was used in order to determine the genotypes for the IL27 T4730С polymorphism and enzyme-linked immunosorbent assay to measure the serum IL27 level.

RESULTS

Carriers of the T4730С polymorphism were found to have a 6-fold [95% confidence intervaI (CI)=1.83-19.63, p=0.002] increased risk for MS. Univariate logistic regression analysis showed an increased frequency of the TC4730 heterozygous genotype (39.2% vs. 9.7%) and also of the C4730 allele (27.45% vs. 8.06) in patients compared to controls, with a 6.02-fold increased risk (95% CI=1.61-22.46, p=0.006) and a 4.31-fold increased risk (95% CI=1.57-11.87, p=0.002) of developing MS. IL27 levels were significantly lower in patients compared to controls (12.35 versus 14.34 pg/ml, p=0.039), without significant differences between genotypes. Multivariate logistic analysis showed that IL27 T4730C polymorphism (odds ratio=6.272, 95% CI=1.84-21.40, p=0.003) and smoking (odds ratio=4.214, 95% CI=1.39-12.74, p=0.011) represented independent risk factors for MS.

CONCLUSION

Our study provides a possible link between IL27 level and IL27 T4730C gene polymorphism and the risk for developing MS in a Romanian population.

Biomarkers of pediatric obstructive sleep apnea syndrome and the assessment of quality of life before and after adenotonsillectomy

The study aims to explore the inflammatory cytokines and oxidative stress in children with obstructive sleep apnea syndrome (OSAS) triggered by adenoids and/or tonsillar hypertrophy and their changes after adenotonsillectomy (AT) and to investigate the associated behavioral disorders in OSAS, before and after AT. Thirty patients with OSAS and 20 healthy children, aged 3 - 13 years were included in the study. According to apnea-hypopnea index (AHI), OSAS children were classified into 3 groups: mild (n = 19), moderate (n = 5), and severe OSAS (n = 6). Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α, malondialdehyde (MDA) and antioxidant enzymes activities were assessed in serum, preoperative and 6 weeks after AT. TNF-α, IL-6 and malondialdehyde levels were also estimated in adenoid and tonsils tissues. A Pediatric Sleep Questionnaire was completed by the parents before and after AT. As a result of the study, we obtained the following results: TNF-α, IL-6 and malondialdehyde evaluated preoperative increased in serum and tissues in OSAS, especially in severe disease compared to mild and moderate forms. Six weeks after AT, AHI diminished significantly in OSAS, as well as the inflammatory markers and malondialdehyde, in parallel with significant improvement of antioxidant enzymes activities. Daytime sleepiness, hyperactivity and attention deficit in OSAS, even in mild disease were present, with significant improvements of obstructive symptoms after AT. We conclude that OSAS caused by adenoids and/or tonsillar hypertrophy led to changes in the blood parameters, with significant improvement after AT. Postoperatively, a significant improvement in sleep quality and behavior in OSAS patients was also observed.

A study of oxidative stress and pulmonary damage after silica instillation in rats and the effect of curcumin administration

BACKGROUND

The authors' aim was to study the dynamics of oxidative stress in experimental exposure to silica dust, to evaluate the histopathological findings in the phase preceding the formation of fibrous/fibrohyaline pulmonary nodules, and to assess the effects of curcumin administration.

MATERIAL AND METHODS

The research was performed on 48 male Wistar rats with an average weight of 320 g. Overall, 38 rats were instilled with a single dose of 0.3 ml suspension containing 30 mg of a SiO₂/ml saline solution, and were sacrificed 30, 90 and 120 days after instillation; 14 of those sacrificed on days 90 and 120 also received curcumin. The control group included 10 animals which were instilled with a saline solution. Malondialdehyde (MDA), carbonyl proteins (CPs), total thiolic proteins (TPs) and reduced glutathione (GSH) were determined in blood and the lung tissue. The standard technique for pulmonary toxicology developed by Porter was applied to semi-quantitatively assess the histopathological findings.

RESULTS

It was found that MDA had increased significantly early on in both biological environments and remained elevated, and adding curcumin proved beneficial, while CPs only increased moderately in the lung tissue without a curcumin impact. Moreover, TPs dropped abruptly, significantly and persistently in the lung tissue and blood, and were not influenced by curcumin. Finally, GSH decreased significantly and intensely in the lung tissue and blood, with curcumin lowering the levels towards those found within the control group. The histopathological examination identified nodules of a cellular type, without any fibrosis, but with spots of associated lipoproteinosis. The early lesions in the airways and vessels were suggestive of a remodeling process. Curcumin diminished the occurrence of alveolitis but not the remodeling process.

CONCLUSIONS

The study confirms the early onset of oxidative stress in experimental silicosis. It also simultaneously and dynamically researches markers of oxidative stress in blood and the lung tissue. Curcumin proved beneficial on oxidative stress and lesions in the alveolar epithelia, but ineffective in preventing vascular and airway remodeling. Med Pr. 2021;72(3):239-47.

Chitosan Functionalized Magnetic Nanoparticles to Provide Neural Regeneration and Recovery after Experimental Model Induced Peripheral Nerve Injury

(1) Background: Peripheral nerve injuries have a great impact on a patient's quality of life and a generally poor outcome regarding functional recovery. Lately, studies have focused on different types of nanoparticles and various natural substances for the treatment of peripheral nerve injuries. This is the case of chitosan, a natural compound from the crustaceans' exoskeleton. The present study proposes to combine chitosan benefic properties to the nanoparticles' ability to transport different substances to specific locations and evaluate the effects of magnetic nanoparticles functionalized with chitosan (CMNPs) on peripheral nerve injuries' rehabilitation by using an in vivo experimental model. (2) Methods: CMNPs treatment was administrated daily, orally, for 21 days to rats subjected to right sciatic nerve lesion and compared to the control group (no treatment) by analyzing the sciatic functional index, pain level, body weight, serum nerve growth factor levels and histology, TEM and EDX analysis at different times during the study. (3) Results: Animals treated with CMNPs had a statistically significant functional outcome compared to the control group regarding: sciatic functional index, pain-like behavior, total body weight, which were confirmed by the histological and TEM images. (4) Conclusions: The results of the study suggest that CMNPs appear to be a promising treatment method for peripheral nerve injuries.

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-1β, 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-1β. 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.

Quercetin attenuates naso-sinusal inflammation and inflammatory response in lungs and brain on an experimental model of acute rhinosinusitis in rats

This study aimed to investigate the effect of quercetin without intranasal inflammation and oxidative stress in nasal and sinus mucosa, but also in serum, lungs and brain in a rat model of acute nasal and sinus inflammation induced by administration of lipopolysaccharides (LPS) (from Escherichia coli). Wistar rats were divided into five groups of 10 animals each. The control group received an intranasal saline solution once/day, for seven consecutive days. Rats in groups 2 and 3, received low-dose (5 μg) and high-dose (10 μg) of LPS, once/day, for seven consecutive days. Rats in groups 4 and 5, received low-dose (5 μg) and high-dose (10 μg) of LPS and after 2 h, 80 mg/kg of quercetin, once/day for seven consecutive days was administered. After the treatment period, the histopathological examination of nasal and sinus mucosa was performed and levels of cytokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6)) and oxidative stress in the blood, nasal mucosa, lungs and brain were also analyzed. High dose of LPS increased TNF-α, IL-6 and IL-1β levels in serum, nasal mucosa, and lungs homogenates while in brain, this effect was only on TNF-α levels. IL-1β enhanced significantly in serum and mucosa, especially after administration of a high dose of LPS (P < 0.01 and P < 0.05). Histopathological and immunofluorescence analysis revealed acute inflammatory reaction in rats treated with both doses of LPS without significant changes of lipid peroxidation in the studied tissues. Quercetin administration diminished the exudate and degree of inflammation in lamina propria of nasal and sinusal areas, parallel with the decreased secretion of TNF-α (40.2% reduction after the low dose of LPS, and 35.4% reduction after the high dose of LPS) and IL-6 (21.4% reduction after the low dose of LPS and 35.8% reduction after the high dose of LPS). In lungs, quercetin reduced TNF-α (43.3%) and IL-6 levels (24.5%), and in the brain, the protective effect was noticed only on TNF-α (46.5%). The intranasal LPS administration successfully induced acute rhinosinusitis in a rat model and also generated an inflammatory response in the lungs and brain. Intranasal administration of quercetin diminished the nasal inflammation and also exerted protective effect on lungs and partially on brain inflammatory reaction.

Quercetin and curcumin effects in experimental pleural inflammation

Background

The inflammatory mechanisms occur with the highest prevalence in pulmonary pathology in addition to oxidative stress and activation of intracellular signaling pathways. The oxidative stress represents the imbalance between pro-oxidants and antioxidants which can lead to the activation of the oxidative mechanisms with noxious potential to the body. Therefore, finding a therapy that would counteract the injurious effects of free radicals and inflammation is highly attractive. Quercetin is the most active flavonoid, with important anti-inflammatory and antioxidant effects, while curcumin has antioxidant effects that are similar to the standard antioxidants and exerts direct anti-inflammatory activity.

Aims

The aim of this study is to evaluate the antioxidant effects of quercetin and curcumin on an experimental model, pleural inflammation induced by carrageenan.

Methods

Eight groups of adult male rats were used: Ia and Ib – control groups, IIa and IIb – with carrageenan administration, IIIa and IIIb – received curcumin and carrageenan, IVa and IVb – quercetin and carrageenan administration. Blood and lung samples were taken at 4 hours (Ia, IIa, IIIa, IVa groups) and at 24 hours (Ib, IIb, IIIb, IVb groups) after carrageenan injection.

Results

At 4 and at 24 hours, curcumin and quercetin have shown protective systemic effects, decreasing significantly the oxidative stress (malondialdehyde level) and stimulating significantly the antioxidant protection (ceruloplasmin and glutathione levels) compared to the group that received only carrageenan. In the lungs, at 4 hours, the redox misbalance was significantly reduced only in animals that were treated with quercetin, modifications that were not observed at 24 hours.

Conclusions

In serum, curcumin presented higher antioxidant effects, compared to quercetin. In lungs, quercetin administration showed superior beneficial effects, but only temporarily.

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-1β, 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-1β, 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.

UV-light mediated green synthesis of silver and gold nanoparticles using Cornelian cherry fruit extract and their comparative effects in experimental inflammation

The purpose of our study is to investigate the comparative effects of materials based on silver and gold nanoparticles functionalized with polyphenols from Cornus Mas extract (AgNPs-CM and AuNPs-CM) in vivo on experimental inflammation. The nanoparticles were obtained at room temperature under UV irradiation and were characterized by different methods: ultraviolet-visible spectroscopy, transmission electron microscopy, X ray diffraction, Fourier transform infrared spectroscopy and dynamic light scattering. The modulatory effects of AgNPs-CM and AuNPs-CM on inflammation were quantified by oxidative stress parameters, pro and anti-inflammatory cytokines levels and apoptosis assessment at 2 h, 24 and 48 h after induction of inflammation with carrageenan in the paw tissue of Wistar rats. Our results showed that silver and gold nanoparticles only partial and for a short period have mobilized the antioxidant defense mechanisms. In addition, they diminished inflammation and apoptosis in the early stage while later, at 48 h, exerted an immunomodulatory effect, activated ERK ½ and induced apoptosis. The photoreduced silver and gold nanoparticles, functionalized with natural compounds, modulated the inflammation in a similar manner in the soft tissue injected with carrageenan. In order to decipher the mechanisms involved in interactions of metallic nanoparticles with biological systems and for a complete assessment of the risks and benefits of these products in clinical practice long term studies are necessary.

In vivosilymarin’s antioxidant and anti-apoptotic effects on photodynamic therapy’s responsiveness

Several studies have shown that some anti-oxidant natural compounds in combination with photodynamic therapy (PDT) can enhance the effectiveness of treatment. The aim of this study is to evaluate the effect of silymarin (SIL) in combination with 5,10,15,20-tetra-sulphonato-phenyl-porphyrin (TSPP) based photodynamic therapy, on experimental tumors. 30 Wistar rats with Walker carcinosarcoma, were divided into 6 groups: group 0 (control) — control, untreated group; group 1 (TSPP) — one dose of TSPP; group 2 (SIL) — silymarin; group 3 (PDT) — TSPP and irradiation 24 h after; group 4 (SIL[Formula: see text]PDT) — silymarin, TSPP and irradiation 24 h after; group 5 (SIL[Formula: see text]IR) and group 6 (IR) — irradiation and in addition, group 5 received SIL. Silymarin administered before photodynamic therapy decreased the lipid peroxidation ([Formula: see text] < 0.05) and modulated the antioxidant defense in tumor treated with PDT and silymarin suggesting that silymarin administration along with photodynamic therapy has an anti-oxidant effect. The caspase — 8 level and -3 activity increased in PDT and PDT [Formula: see text] SIL groups compared to the control; between the two groups there was a significant difference in term of apoptosis in favor to PDT. In conclusion, silymarin administration inhibited the reactive oxygen species generation and reduced the tumoral cells’ apoptosis, suggesting that natural compound administered before photodynamic therapy did not improve the therapy’s effect.

The effect of Sambucus nigra L. extract and phytosinthesized gold nanoparticles on diabetic rats

Nanomaterials such as gold nanoparticles (NPs) conjugated with natural products have shown good results in lowering the glycated hemoglobin and have an anti-inflamatory effect. The aim of our study is to evaluate the antidiabetic effect of NPs functionalized with Sambucus nigra L. (SN) extract on experimental model of diabetes in rats. Diabetes was induced to 18 Wistar male rats (n=6) by a single intramuscular injection of streptozotocin (30mg/kg body weight - b.w.). SN extract (15mg/kg b.w.), NPs (0.3mg/kg b.w.) and vehicle (normal saline) were administered by gavage once a day, every morning, for 2 weeks. Other 18 animals were used as control groups and were treated with the same compounds, at the same time. Afterwards, blood, liver and muscle samples were taken to assess the oxidant/antioxidant status and the liver for the evaluation of metalloproteinases (MMP)-2 and 9 activities, COX-2 and NFKB expressions and for immunohistochemistry. Serum glycemia, cholesterol, alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) were also measured. The administration of NPs extract increased the muscle and systemic GSH/GSSG ratio in the diabetic group vs. diabetic (p<0.03) or non-diabetic groups treated with vehicle (p<0.05) and decreased MDA levels compared to non-diabetic group (p<0.05). COX-2 expression (p<0.0001) and proMMP-2 activity (p<0.05) decreased after pretreatment with NPs in parallel with the reduction of Kupffer cells percent (<0.001). No morphological abnormalities were detected in histopathology. NPs present a great potential for further usage as adjuvants in the diabetic therapy due to the increase of antioxidant defence and reduction of MMPs activity and inflammation in liver tissue.

Resveratrol and curcumin as protective agents in an experimental rat model of intestinal ischemia and reperfusion

The aim of this study was to evaluate the protective effects of resveratrol and curcumin in an experimental rat model of intestinal ischemia–reperfusion (I/R). Forty-eight adult Wistar rats were used: 12 animals undergoing the sham surgery and 36 animals undergoing laparotomy, with 15 min of mesentric artery clamping. The animals from the latter group (n = 12) were pretreated, for 1 week, with vehicle (CTR), resveratrol (RES), and curcumin (CUR). After 1 h and 6 h of reperfusion, respectively, cyclooxigenase (COX)-2, mucin-1, E-cadherin, nuclear factor (NK)-κB expressions, and tumor necrosis factor related apoptosis-inducing ligand (TRAIL) were assessed in the small intestine. Oxidative stress markers were determined in tissue homogenate and serum, and histopathological analysis was performed. Pretreatment with RES decreased the expression of COX-2 and NF-κB at both intervals and increased E-cadherin (p < 0.05) and mucin-1 production after 1 h. CUR had a beneficial effect on COX-2, NF-κB, and E-cadherin expressions, both after 1 h and after 6 h (p < 0.0001). The two compounds increased TRAIL levels and had a protective effect on oxidative stress and histopathological lesions, both after 1 h and after 6 h. Our results suggested that RES and CUR had beneficial effects in intestinal I/R and may represent a promising option for complementary treatment of this pathological condition.

Modulatory effects of caffeine on oxidative stress and anxiety-like behavior in ovariectomized rats

Menopause is accompanied by enhanced oxidative stress and behavioral changes, effects attenuated by antioxidants. The aim of this study was to evaluate the effects of caffeine on behavior and oxidative stress in an experimental model of menopause. Female rats were divided into the following groups: sham-operated (CON), sham-operated and caffeine-treated (CAF), ovariectomized (OVX), ovariectomized and caffeine-treated (OVX+CAF). Caffeine (6 mg/kg) and vehicle were administered for 21 days (subchronic) and 42 days (chronic), using 2 experimental subsets. Behavioral tests and oxidative stress parameters in the blood, whole brain, and hippocampus were assessed. The subchronic administration of caffeine decreased the lipid peroxidation and improved the antioxidant defense in the blood and brain. The GSH/GGSG ratio in the brain was improved by chronic administration, with reduced activities of antioxidant enzymes and enhanced nitric oxide and malondialdehyde levels. In particular, the lipid peroxidation in the hippocampus decreased in both experiments. The rats became hyperactive after 21 days of treatment, but no effect was observed after chronic administration. In both experimental subsets, caffeine had anxiolytic effects as tested in elevated plus maze. The administration of low doses of caffeine, for a short period of time, may be a new therapeutic approach to modulating the oxidative stress and anxiety in menopause.

Protective effect of curcumin on diazepam-induced behavioral changes and oxidative stress in rats

Introduction

Curcumin (CUR), a polyphenolic compound, extracted from Curcuma longa, is known for its neuroprotective, antioxidant and anti-inflammatory effects.

Objectives

To evaluate the effect of CUR on ambulatory activity, spatial working memory and on oxidative stress in rats induced by Diazepam (DZP) administration.

Aims

To analyze whether CUR may improve the cognitive performance and offer systemic protection from oxidative stress.

Methods

The effect of CUR on DZP-induced memory impairment and oxidative stress was studied on Wistar rats. Group I received a vehicle, group II – vehicle and CUR, group III – vehicle and DZP, group IV – vehicle, CUR and DZP. CUR (150 mg/kg bw) and vehicle were orally administered for five weeks long. DZP (2 mg/kg bw) was administered i.p. 20 minutes before the behavioral tests. Behavioral tests, i.e. Open Field and Y Maze Test, were performed. Malondialdehyde and reduced glutathione/oxidized glutathione ratio were determined in the serum and brain tissue homogenate. Hippocampal sections were histologically assessed. The data were statistically analyzed by one-way ANOVA, followed by Dunns post-test.

Results

DZP decreased (P < 0.01) the number of spontaneous alternations, as compared to control group, thus suggesting an impairment of spatial working memory. Behavioral tests revealed no enhancing effect of CUR on spontaneous alternation behaviors in Y Maze. CUR reversed (P < 0.01) the inhibitory effect of diazepam (P < 0.05) on the ambulatory activity in OFT and decreased the lipid peroxidation in the serum (P < 0.05).

Conclusions

The results show that CUR may offer systemic protection from oxidative stress, thus improving the cognitive performance.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Oxidative stress in blood and testicle of rat following intraperitoneal administration of aluminum and indium

Aluminum (Al) and indium (In) have embryotoxic, neurotoxic and genotoxic effects, oxidative stress being one of the possible mechanisms involved in their cytotoxicity. We have recently demonstrated that indium intraperitoneal (ip) administration induced histological disorganization of testicular tissue. In the present research we aimed at investigating the effect of Al and In ip administration on systemic and testicular oxidative stress status. Studies were performed on Wistar rats ip injected with Al, In or physiological solution for two weeks. Our results showed that In significantly decreased the absolute weight of testicles. Measurements of lactate dehydrogenase (LDH) and paraoxonase (PON) activities showed that In induced a significant augmentation in the first parameter but no changes were observed in the second. Both Al and In caused oxidative stress in testicles by increasing malondialdehyde (MDA) and protein carbonyls (PC) production. Concomitantly, thiol group (-SH) and glutathione (GSH) level were enhanced in the testicles. In the blood, while concentrations of MDA was not changed, those of GSH was significantly decreased in the Al and In groups. Our results indicated that Al and In cause oxidative stress both in blood and testicles but In has cytotoxic effect as well as negative impact on testicle weights. These findings could explain the testicular histological alterations previously described after In ip administration.

Non-invasive oxidative stress markers for liver fibrosis development in the evolution of toxic hepatitis

Oxidative stress is related to the liver fibrosis, anticipating the hepatic stellate cells' (HSC) activation. Our aim was to correlate oxidative stress markers with the histological liver alterations in order to identify predictive, noninvasive parameters of fibrosis progression in the evolution of toxic hepatitis.CCl4 in sunflower oil was administered to rats intragastrically, twice a week. After 2, 3, 4 and 8 weeks of treatment, plasma levels of malondialdehyde (MDA), protein carbonyls (PC), hydrogen donor capacity (HD), sulfhydryl groups (SH), and glutathione (GSH) were measured and histological examination of the liver slides was performed. Dynamics of histological disorders was assessed by The Knodell score. Significant elevation of inflammation grade was obtained after the second week of the experiment only (p=0.001), while fibrosis started to become significant (p=0.001) after 1 month of CCl4 administration. Between plasma MDA and liver fibrosis development a good correlation was obtained (r=0.877, p=0.05). Correlation between PC dynamics and liver alterations was marginally significant for inflammation grade (r=0.756, p=0.138). HD evolution revealed a marginally inverse correlation with inflammation grade (r=-0.794, p=0.108). No correlations could be established for other parameters with either inflammation grade or fibrosis stage.Our study shows that MDA elevation offers the best prediction potential for fibrosis, while marginal prediction fiability could be attributed to high levels of plasma PC and low levels of HD.

Oxidative photodamage induced by photodynamic therapy with methoxyphenyl porphyrin derivatives in tumour-bearing rats

The oxidative effects of photodynamic therapy with 5,10,15,20-tetrakis(4-methoxyphenyl) porphyrin (TMP) and Zn-5,10,15,20-tetrakis(4-methoxyphenyl) porphyrin (ZnTMP) were evaluated in Wistar rats subcutaneously inoculated with Walker 256 carcinoma. The animals were irradiated with red light (λ = 685 nm; D = 50 J/cm2; 15 min) 3 h after intra-peritoneal administration of 10 mg/kg body weight of porphyrins. The presence of free radicals in tumours after photodynamic therapy with TMP and ZnTMP revealed by chemiluminescence of luminol attained the highest level at 18 h after irradiation. Lipid peroxides measured as thiobarbituric-reactive substances and protein carbonyls, which are indices of oxidative effects produced on susceptible biomolecules, were significantly increased in tumour tissues of animals 24 h after photodynamic therapy. The levels of thiol groups and total antioxidant capacity in the tumours were decreased. The activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase were also increased in tumour tissues after photodynamic therapy. Increased levels of plasma lipid peroxides as well as changes in the levels of erythrocyte antioxidant enzyme activities suggest possible systemic effects of photodynamic therapy with TMP and ZnTMP.

L-carnitine decreases oxidative stress induced by experimental hypobaric hypoxia

INTRODUCTION

It is known that exposure to severe hypobaric hypoxia induces changes of reactive oxygen species (ROS) and antioxidant systems. L-carnitine, a natural compound, has an antioxidant effect and decreases lipid peroxidation. The aim of this study was to investigate the protective effects of L-carnitine treatment on oxidative stress induced by exposure to hypobaric hypoxia.

MATERIAL AND METHODS

30 male Wistar rats were divided into 3 equal-size groups: 1st group - a control group, kept in normoxic conditions; 2nd group - rats exposed to hypobaric hypoxia in the barochamber (simulated high altitude equivalent to 5500 meters) for a 14-day placebo; 3rd group - rats exposed to hypobaric hypoxia for 14 days and treated with L-carnitine (L-carnitine, 100 mg/kg) every day. After 14 days, the serum levels of lipid peroxides expressed by the value of malondialdehyde (MDA), and the serum levels of carbonylated proteins (CP), glutathione (GSH) and donor hydrogen ability (DHA) were determined for all rats.

RESULTS

The results indicated an increase in MDA and CP levels, after the exposure to hypobaric hypoxia. L-carnitine significantly decreased (p <0.05) the levels of the MDA and CP and significantly increased (p <0.05) the serum antioxidant capacity: glutathione and DHA.

CONCLUSION

This study suggests that the administration of L-carnitine can be beneficial in attenuating the oxidative stress associated with exposure to high altitude.

Antioxidant effects of a grape seed extract in a rat model of diabetes mellitus

In the present study we investigated the anti-hyperglycaemic and antioxidant effect of grape seed extract, a polyphenolic flavonoid, in normal and streptozotocin-induced diabetic Wistar rats. Adult male Wistar rats were divided into three groups: Group I: non-diabetic control; Group II: diabetic control; Group III: diabetic rats treated with grape seed extract, administered via an intragastric tube (0.6 ml/rat), at a dose of 100 mg/kg for 20 consecutive days after the induction of diabetes mellitus. Diabetes was induced by an i.p. injection with streptozotocin for groups II and III. TheTBARS, carbonylated proteins, were measured in the plasma and in the supernatant of liver homogenisates, and superoxide dismutase and catalase were measured in the haemolysates of RBCs and supernatant of liver homogenisates. The results showed that oral administration of grape seed extract (100 mg/kg/day) reduced the levels of lipid peroxides and carbonylated proteins and improved the antioxidant activity in plasma and hepatic tissue in rats treated with grape seed natural extract as compared with the diabetic control rats. These results suggested that the grape seed extract enhanced the antioxidant defence against reactive oxygen species produced under hyperglycaemic conditions, hence protecting the liver cells.