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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. [ABSTRACT FROM AUTHOR]

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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 apoptosisinducing 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. Key words: resveratrol, curcumin, oxidative stress, inflammation, intestinal ischemia. Cette etude avait pour but d'evaluer les effets protecteurs du resveratrol et de la curcumine dans un modele d'ischemie-reperfusion (I/R) intestinale chez le rat. Nous avons utilise 48 rats Wistar adultes : 12 animaux ont subi une intervention chirurgicale factice (sham) et 36 animaux ont subi une laparotomie avec occlusion de l'artere mesenterique de 15 minutes. Nous avions pretraite les animaux de ce dernier groupe avec le vehicule (Tem.), du resveratrol (RES) ou de la curcumine (CUR) pendant une semaine (n = 12 dans chacun des cas). Les animaux respectifs ont subi une reperfusion d'une heure ou de 6 heures, puis nous avons quantifie l'expression de la cyclooxygenase (COX)-2, de la mucine-1, de l'E-cadherin, ainsi que du facteur nucleaire (NK)-κB et du ligand inducteur de l'apoptose apparente au facteur de necrose tumorale (TRAIL) dans l'intestin grele. Nous avons evalue le stress oxydatif dans des homogenats de tissu et du serum a l'aide de marqueurs, et realise des examens histopathologiques. Le pretraitement avec le RES a entraine une diminution de l'expression de la COX-2 et du NF-κB (aux deux durees de perfusion) et une augmentation de la production d'E-cadherin (p < 0,05) et de mucine-1 (avec une reperfusion d'une heure). La CUR a eu un effet avantageux sur l'expression de la COX-2, du NF-κB et de l'E-cadherin (tant avec une reperfusion d'une heure que de 6 heures (p < 0,0001)). Les deux substances ont permis d'augmenter les taux de TRAIL et avaient un effet protecteur contre le stress oxydatif et dans les lesions visibles a l'examen histopathologique (tant apres une reperfusion d'une heure que de 6 heures). Nos resultats laissaient entendre que le RES et la CUR auraient des effets avantageux en cas d'ischemie intestinale et qu'ils pourraient representer un choix de traitement complementaire prometteur contre cet etat pathologique. [Traduit par la Redaction] Mots-cles : resveratrol, curcumine, stress oxydatif, inflammation, ischemie intestinale., Introduction Acute mesenteric ischemia, due to reduced splanchnic circulation followed by early revascularization, is the underlying mechanism that describes the phenomenon of intestinal ischemia-reperfusion (I/R). Intestinal I/R is a clinical [...]

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. Key words: caffeine, ovariectomy, brain, blood, oxidative stress, behavior, neuroprotection, rats. La menopause s'accompagne d'une augmentation du stress oxydatif et de changements comportementaux; ces effets sont attenues par les antioxydants. Le but de cette etude etait d'evaluer les effets de la cafeine sur le comportement et le stress oxydatif dans un modele experimental de menopause. Des rates ont ete reparties dans les groupes suivants : intervention chirurgicale factice (CON), intervention chirurgicale factice et administration de cafeine (CAF), ovariectomie (OVX), ovariectomie et administration de cafeine (OVX+CAF). Nous avons administre la cafeine (a 6 mg/kg) et le vehicule pendant 21 jours (administration subchronique) et 42 jours (administration chronique) pour former 2 sous-ensembles experimentaux. Nous avons effectue des tests comportementaux et evalue des parametres du stress oxydatif dans le sang, le cerveau entier et l'hippocampe. L'administration subchronique de cafeine a entraine une diminution de la peroxydation lipidique et l'amelioration de la defense contre l'oxydation dans le sang et le cerveau. Dans le cerveau, nous avons observe que l'administration chronique de cafeine permettait d'ameliorer le rapport GSH/GGSG tout en diminuant l'activite des enzymes antioxydantes et en augmentant les taux d'oxyde nitrique et de malondialdehyde. Plus precisement, la peroxydation lipidique diminuait dans l'hippocampe, et ce, dans les deux conditions experimentales. Les rates sont devenues hyperactives apres 21 jours de traitement, mais nous n'avons observe aucun effet apres l'administration chronique. En revanche, le test du labyrinthe en croix sureleve a permis d'observer que la cafeine avait des effets anxiolytiques dans les deux sous-ensembles. En somme, l'administration de faibles doses de caffeine pendant une courte periode pourrait constituer une nouvelle approche therapeutique visant a moduler le stress oxydatif et l'anxiete pendant la menopause. [Traduit par la Redaction] Mots-cles: cafeine, ovariectomie, cerveau, sang, stress oxydatif, comportement, neuroprotection, rats., Introduction Menopause, defined as the permanent cessation of menstruation, is a physiological process that occurs in women around the age of45-55 years, being linked to the loss of ovarian activity. [...]

The article titled "Evaluating Hepatic Toxicity of Chitosan and Chitosan-Functionalized Iron Oxide Nanoparticles in a Rat Model of Peripheral Nerve Injury -- Relevance for Rehabilitation Medicine" by Nadina Liana Pop et al. was published in the Balneo & PRM Research Journal in June 2024. The study examines the potential liver toxicity of chitosan and chitosan-functionalized iron oxide nanoparticles in a rat model of peripheral nerve injury. The authors aim to determine the relevance of these findings for rehabilitation medicine. The article provides the necessary references and contact information for further exploration. [Extracted from the article]

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Resveratrol is a polyphenol with important antioxidant and antiinflammatory roles. Loratadine, as a selective inverse-agonist of peripheral receptor H1, is described as an anti-allergic substance with potential antiinflammatory effects. We aimed to assess the protective capacity of loratadine against oxidative stress produced by inflammation with carrageenan in comparison with a well-known antioxidant compound, resveratrol. Our results showed that resveratrol and loratadine had no protective anti-inflammatory effects in inflamed skin. As expected, resveratrol had antioxidant effects in serum and in liver. Loratadine developed oxidative stress in tegument and serum. In this experimental model, our results do not sustain the initial hypothesis that loratadine could have a protective effect in inflammation, and, in the contrary, is capable of increasing it, by producing an oxidative stress. [ABSTRACT FROM AUTHOR]

The aim of our study was to assess the hepatoprotective and antioxidant effects of chitosan as compared with vitamin E in experimental toxic liver injury induced by carbon tetrachloride. Blood and liver samples were collected in order to assess hepatocytolisis (AST, ALT), oxidative stress (MDA, carbonyl proteins, GSH, SH groups, SOD and CAT), and histopathology examination was performed in order to asses inflammation and fibrosis. Liver enzymes level showed a significant, progressive increase after repeated exposure to CCl4, first in liver tissue, then in the blood. Malondialdehyde and carbonyl proteins significantly increased, and GSH progressively decreased. Chitosan increased the GSH in the liver tissue to a value superior to that of the control group and decreased the AST and MDA level both in the liver and in the blood to values comparable to that of control group. Chitosan decreased carbonyl proteins level in the liver but slightly increased them in the blood. Vitamin E had similar effects concerning liver function and lipid peroxidation, but paradoxically, it induced protein peroxidation both in blood and in liver tissue. Histological modifications support the observed biochemical changes. [ABSTRACT FROM AUTHOR]

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Solar ultraviolet radiation (UV) is a major cause of ocular injury contributing to photokeratitis, cataract and pterygium development. The aim of the study was to investigate the oxidant/antioxidant status of Wistar rat eyes after exposure to various doses of UVB in correlation with morphological and structural changes. Five groups of 8 animals each, randomly divided, were treated as follows: group 1: control, no UVB irradiation; group 2: a single UVB exposure to a dose of 45 mJ/cm²; group 3: a single UVB exposure to 90 mJ/cm²; group 4: a single UVB exposure to 180 mJ/cm²; group 5: a single UVB exposure to 360 mJ/cm². At 24 hrs after UVB irradiation the animals were anaesthetized and sacrificed by cervical dislocation. The rat eyes from 5 animals were extracted and used for biochemical determinations and from 3 animals were harvested and used for histopathological investigation. Our results demonstrated that a single UVB exposure at different doses disturbs the oxidant-antioxidant balance in the eye tissues by lipid peroxides generation, activation of CAT and SOD and adaptative increasing of GSH levels, particularly at high doses. Twenty hours following UVB irradiation the cornea showed significant lesions: inflammation, hemorrhage, superficial/deep ulcerous keratitis and epithelial exfoliation. Severity of injuries was dose-dependent. These data suggest that oxidative stress may be responsible for the corneal lesions induced by UVB irradiation. [ABSTRACT FROM AUTHOR]

Background. Vitiligo is a skin disease whose etiology is far from being completely elucidated. Many therapeutic methods have not proven to be fully effective, therefore phenytoin, through its immunomodulatory activity, has been proposed as a therapeutic agent in vitiligo. No studies showing the efficacy of phenytoin in this condition have been published so far. Aims. Evaluation of pro-oxidant and antioxidant markers after two therapeutic methods, topical PUVA therapy and topical therapy with phenytoin respectively, to assess the effectiveness of phenytoin in vitiligo. Patients and method. Oxidative stress was evaluated by determining the balance between oxidants (malondialdehyde) and antioxidant systems (hydrogen donor capacity). Eligible patients were enrolled in two groups according to the treatment studied, namely phenytoin topical gel 2% and topical photochemotherapy. Results. The treatment with topical phenytoin reduced lipid peroxidation processes in 90% of patients and stimulated the antioxidant systems of the skin in 80% of the cases, similar to a known therapeutic method, topical PUVA therapy. Conclusions. Topical applications of phenytoin may be effective in the treatment of vitiligo, by its efficacy on the oxidant/antioxidant balance. [ABSTRACT FROM AUTHOR]

Background. Studies regarding the serum biochemical changes in redox homeostasis determined by chronic immobilization led us to investigate the serum and muscular effects of physical remobilization by exercise on the oxidant/antioxidant balance. Aims. We investigated whether physical exercise preceded by complex stress through repeated immobilization can influence the prooxidant effects of immobilization. Methods. The research was performed in 3 groups of white male Wistar rats: group I - control group, sedentary animals; group II - animals exercise trained for 28 days; group III - animals exposed to anakinetic stress (immobilization) for 3 hours daily and exercise trained for 28 days. The indicators of the oxidant/antioxidant balance were determined in the serum and muscle tissue. The moments included in the study were T1 and T28. Results. The chronic combined intermittent stress program - physical exercise preceded by immobilization (group III) induced, compared to the exercise trained group (group II), a diminution of oxidative stress with a significant decrease in serum malondialdehyde and a significant diminution of antioxidant defense on account of muscle glutathione, with insignificant changes in the other studied indicators, which supports the use of glutathione in antioxidant defense. Conclusions. Daily training for 28 days induces an increase of oxidative stress in the serum and muscles, a decrease of antioxidant defense in the serum and an increase of it in muscles. Daily training preceded by anakinetic stress for 28 days determines a decrease of oxidative stress in the serum and a decrease of antioxidant defense in muscles. [ABSTRACT FROM AUTHOR]

Background. Dupuytren's Disease (DD) means the fibrous retraction of palmar and digital aponeurosis. Up to now, the intrinsic ethiopathogenetic mechanisms of DD are still not completely known. Aims. We aimed to investigate:1) the relationship between oxidative stress, inflammatory mechanisms and DD; 2) the alterations induced by diabetes mellitus (DM) in the aforementioned pathogenetic mechanisms a of DD. Material and method. 36 cases bearing DD lesions, as well as 25 control cases were selected between 2005-2007. According to presence of DM, test group was further divided into two sub-groups (presence of DM, n=28; absence of DM, n=8). Collection of urine and saliva was performed for all included cases. Malondialdehyde (MDA), hydrogen donor activity (HD) were assessed on both urinary and salivary samples. Also, ceruloplasmin (CP) was measured in saliva for all patients. Results. MDA levels were superior in test group as compared to control group for urinary samples (p=0.011). HD, CP presented lower values in DD group. Patients presenting DD and DM association recorded significantly different levels of urinary MDA (p=0.004), HD (p=0.045) as well as salivary CP levels (p=0.025) as compared to DD with no glycemic equilibrium alterations group. Conclusions. Dupuytren contracture, both in the form of stand-alone disease and secondary manifestation of DM is associated with oxidative balance alteration and oxidative injury in saliva and urine. By means of innate mechanisms, diabetes alleviates the DD-specific oxidative injury. [ABSTRACT FROM AUTHOR]

Chronic stress is a major factor that contributes to several disorders. A common animal model, performed in order to evaluate the environmental experimentally-induced-stress is hypothermia. L-Carnitine is a natural substance required in the energetic metabolism of the mammals, which also has an antioxidant function. The aim of the present study was to evaluate the effect of chronic hypothermic stress on oxidant/antioxidant balance in the serum and tissues, (liver and muscle), on rats with and without carnitine supplementation. Rats were divided randomly into four groups often rats each: control group (I); hypothermic stress (II) - exposed to cold stress; supplemented with carnitine (HI) supplemented with carnitine and exposed to hypothermic stress (TV). Our experimental results showed that chronic hypothermic stress increases the oxidative stress (OS) indicators in serum and tissues and decreased those of antioxidant (AO) defense. Carnitine supplementation in chronic hypothermic stress conditions had benefic effects on OS and AO defense indicators, this compound being likely to have favorable effects in an experimental hypothermic stress model. [ABSTRACT FROM AUTHOR]

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Myringosclerosis is a common sequel of the ventilation tube treatment of otitis media. Recent studies have established the relationship between reactive oxygen species (ROS) and myringosclerosis.The aim of this experimental study was to investigate the temporal change of oxidants/antioxidants balance at 6, 12, 24, and 48 hours after the myringotomy. Fifty healthy adult male Wistar albino rats, weighing approximate 250-300 g, were randomly separated into five groups (n = 10 rats/group): first group ,of control, nonmyringotimized and four groups myringotimized unilaterally on the left ear. The tympanic membranes were collected from sacrificed rats for biochemical evaluation of parameters of oxidants/antioxidants balance from 1st group and in 6 hours from 2nd group, in 12 hours from 3rd group, in 24 hours from 4th group and in 48 hours from 5th group. The index oxidants were malondialdehyde and carbonyl proteins and the index antioxidants were hydrogen donor ability and sulfhydril groups. Results and conclusions: The changes of oxidants/antioxidants balance and oxidative stress appear after myringotomy in 6 hours and increase in 12, 24, and 48 hours. Myringosclerosis develops promptly after myringotomy. [ABSTRACT FROM AUTHOR]

Carbon tetrachioride is an organic solvent known for its hepatotoxicity. Its effects are due to CCl3 radical production. Chitosan is a natural antioxidant obtained from the exoskeleton of the crustaceous; it protects the liver against the oxidative stress. We used 40 female Wistar rats (weight 23 0±25 gr.) divided into 4 equal groups. Group I was the control one; Group II received a unique dose of 3 ml/kg CCl4 by gavage; Group III received daily 5 mg/kg vitamin E i.m. for a week before the CCl4 administration. Group IV received daily 3 mg/kg chitosan i.p. for a week before the CCl4 administration. 24 hours after the CCl4 have been given, blood and liver tissue samples were taken. We assessed the oxidative stress markers (malondialdehyde) and antioxidant defence markers (hydrogen donors' capacity and reduced glutathione) both from serum and liver tissue. CCl4 acute administration induced oxidative stress especially in the liver tissue (malondialdehyde level increases, while glutathione level decreased). However, for the animals that have been protected with chitosan, the oxidative stress markers had almost similar values to those of the control group. The histopathological findings confirm the results. Therefore, chitosan has a protective effect against liver injuries induced by acute exposure to CCl4. [ABSTRACT FROM AUTHOR]

The oxidative effects of photodynamic therapy (PDT) with 5-aminolevulinic acid (5-ALA) and chitosan (CS) were evaluated in Wistar rats s. c. inoculated with Walker 256 carcinoma. The animals were irradiated with red light (λ=685 nm, D=50 J/cm², 15 rain) 3h after i.p administration of 250 mg/kg b.w. 5-ALA, 1.5-mg/kg b.w. CS or an associated treatment of 5-ALA and CS. The levels of lipid peroxides and protein carbonyls were determined in plasma and tumor tissues. The antioxidant capacity of plasma and tumor tissues as well as the antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) activities in erythrocytes and tumors were assessed. 24hs after the treatment, in 5-ALA treated animals the levels of lipid peroxides and protein carbonyls were significantly increased both in plasma and tumors. 5-ALA PDT decreased the erythrocyte antioxidant enzymes activities. An associated treatment with CS and 5-ALA produced the reduction of the lipid peroxides and protein carbonyls in plasma and the recovery of antioxidant enzymes activities. These results suggest the antioxidant properties of CS. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Medica Transilvanica is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. Cerebral hypoxia and ischemia are the major causes of perinatal mortality resulting in central nervous system injury. Hypoxia and ischemia produce massive brain damage and one of the most important mechanisms in the lesion pattern is oxidative stress. Aims. The objectives of this study are to assess the effects of resveratrol pretreatment in a cerebral hypoxic-ischemic (HI) newborn rat model as well as the influence that hypothermia has on redox parameters in this experimental model and the effects of the combined therapy from the oxidative stress perspective. Material and method. The experiment was performed on eighty newborn Wistar rats of both genders, weighing about 10 grams, placed into eight groups: control, treated with resveratrol (RES), RES+HI insult, RES+hypothermia, subjected to hypothermia only, HI insult+normothermia, HI insult+hypothermia. Resveratrol was administrated in a dose of 20 mg/kg/day for seven days as premedication. At the end of this period the animals were exposed to hypobaric hypoxia (9% O2+ for 90 minutes) and ischemia (by clamping the right carotid artery). In order to test the effect of combined therapy of resveratrol with hypothermia, several animals were exposed after HI injury to whole body moderate hypothermia (with 4°C) for 3h. After recovery the malondialdehyde level and the activities of superoxide dismutase and glutathione peroxidase were determined in the brain tissue of the newborn rats. Results. MDA levels were increased in the groups receiving resveratrol pretreatment. In the group subjected to simple hypothermia MDA levels were also increased. In the group subjected to HI insult and then to hypothermia, MDA levels were significantly lower. MDA levels were lower also in the group where RES was associated with hypothermia in HI insult context. GPx levels were decreased in groups pretreated with RES and subjected to HI, hypothermia, the same effect in case of hypothermia alone. Only in the group treated with RES was the GPx level higher than in controls. SOD levels were high in the RES pretreated group, but decreased in HI insult. In the group subjected to hypothermia after HI, SOD was significantly higher. Conclusion. The results of this study prove that hypothermia offers better neuroprotection in ischemic brain injuries than resveratrol. The combined therapy influenced the oxidative stress parameters. Hypothermia is a stress factor, but when applied in post-lesion condition, offers protection for the brain. [ABSTRACT FROM AUTHOR]

Aims. The influence of acute O3 and hypobaric hypoxia exposure on tissue redox reactivity during rest and exercise conditions was studied in the brain, myocardium, lungs and striated muscles. Material and methods. The investigation was performed in 3 groups of white male Wistar rats: group I - control group, sedentary rats under normoxia conditions; group II - sedentary rats exposed to acute combined stress: acute O3 + hypobaric hypoxia; group III - animals exposed to acute combined stress, followed by exercise. Exposure was simulated in the hypobaric chamber for 3 days, 20 hours a day, at 2500 m. Ozone exposure was performed for 3 days, 5 min daily. Group III was trained daily for 3 days under normoxia conditions, by the swimming test. In order to measure the indicators of the oxidant/antioxidant (O/AO) balance, on day 3 tissue samples were taken from the brain, myocardium, lungs and femoral quadriceps muscle. Results. Animals undergoing physical exercise after acute combined stress exposure have a significant increase in oxidative stress (OS) in the lungs compared to controls. In the myocardium and striated muscle, there are OS changes similar to those found in sedentary animals exposed to combined stress. In the brain, there is a significant decrease in OS simultaneously with a significant decrease in AO defense compared to both the control group and the sedentary group exposed to combined stress. Conclusions. Physical exercise performed after acute O3 and hypobaric hypoxia exposure induces significant changes in the O/AO balance in pulmonary, myocardial and brain tissue. Major adaptive changes occur in the lungs, where OS and AO defense increase simultaneously. [ABSTRACT FROM AUTHOR]