Biochemical and histopathological evaluation of systemic and ocular toxicity of favipiravir in rats.

Purpose: Favipiravir (FAV) used against COVID-19 is an antiviral drug that causes adverse reactions, such as hyperuricaemia, liver damage, and hematopoetic toxicity. The aim of the study was to investigate the systemic and ocular side-effects of FAV in rats, for the first time.Materials and methods: A total of 18 albino male Wistar rats were used in the study. The rats were divided into 3 groups as the healthy group (HG), the group given 50 mg/kg/day favipiravir (FAV50), and the group given 200 mg/kg/d favipiravir (FAV200). These doses were given to the experimental groups for one week. At the end of the experiment histopathological examinations were performed on the conjunctiva and sclera of the eye. In addition, malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), interleukin-1ß (IL-1ß), and tumor necrosis factor alpha (TNF-α) levels were measured in blood samples taken from rats. Results: Compared to HG, the MDA (1.37 ± 0.61 vs. 4.82 ± 1.40 µmol/mL), IL-1ß (2.52 ± 1.14 vs. 6.67 ± 1.99 pg/mL), and TNF-α levels (3.28 ± 1.42 vs. 8.53 ± 3.06 pg/mL) of the FAV200 group were higher. The levels of tGSH (7.58 ± 1.98 vs. 2.50 ± 0.98 nmol/mL) and SOD (13.63 ± 3.43 vs. 3.81 ± 1.43 U/mL) the FAV200 group were lower than the HG (p < 0.05, for all). The degree of damage to the cornea and sclera of the FAV200 group was quite high according to HG (p < 0.001). Conclusions: FAV can cause damage to rat conjunctiva and sclera by increasing oxidant stress and inflammation at high dose.

Protective Effect of Ramipril Against Oxidant and Proinflammatory Cytokine Damage Induced by Ischemia-Reperfusion in Ovarian Tissue in Rats.

BACKGROUND: It is known that the increase in oxidants and proinflammatory cytokines, as well as the decrease in antioxidants, play a role in ovarian ischemia-reperfusion (I/R) injury. The antioxidant and anti-inflammatory properties of ramipril have been studied in various diseases. This study aims to investigate the effect of ramipril on I/R-induced ovarian damage in rats. METHODS: Rats were divided into healthy (HG), sham (SG), ovary I/R (OIR), and ramipril + ovary I/R (ROIR) groups (n = 6/each group). One hour before the surgical procedures, ROIR was given 2 mg/kg ramipril. The lower abdomen of the SG, OIR, and ROIR was surgically opened. Right ovarian tissues of OIR and ROIR were subjected to 2 hours of ischemia and 6 hours of reperfusion. Then, all animals were euthanized, and their right ovaries were removed. Ovarian tissues were examined for oxidants (malondialdehyde), antioxidants (total glutathione, superoxide dismutase, and catalase), and proinflammatory cytokines (nuclear factor kappa-B, tumor necrosis factor-alpha, interleukin 1 beta, and interleukin-6) analysis was performed. Tissues were examined histopathologically. RESULTS: The ovarian tissue of the OIR, which underwent the I/R procedure, exhibited a significant increase in oxidant and proinflammatory cytokine levels, along with a decrease in antioxidant levels (P < .001). Ramipril suppressed the I/R-induced increase in oxidants and pro-inflammatory cytokines and the decrease in antioxidants (P < .001). Ramipril also attenuated I/R-induced histopathological damage in ovarian tissue (P < .05). CONCLUSION: Ramipril treatment may be a treatment strategy to protect ovarian tissue against oxidative and inflammatory damage of I/R.

Effect of Usnea longissima ethyl acetate extract on acute oxidative and inflammatory lung damage from Staphylococcus aureus infection in rats.

The role of oxidants and proinflammatory cytokines in the pathogenesis of pneumonia caused by Staphylococcus aureus (S. aureus) has been demonstrated. The present study aims to investigate the protective effect of ethyl acetate extract (EtOAc) obtained from Usnea longissima (UL) against acute oxidative and inflammatory lung damage due to S. aureus infection in rats. Albino Wistar-type male rats were divided into three groups: Healthy (HG), S. aureus inoculated (SaG), and S. aureus inoculated + ULEtOAc administered (SUL). SaG (n = 6) and SUL (n = 6) group rats' left nostrils (excluding HG) were inoculated with 0.1 ml bacterial mixture. After 24 hours, ULEtOAc (50 mg/kg) was administered orally to the SUL group, and the same volume of normal saline was administered orally to the HG (n = 6) and SaG groups. This procedure was performed once a day for seven days. Levels of oxidant and antioxidant parameters such as malondialdehyde (MDA) and total glutathione (tGSH), as well as pro-inflammatory cytokine levels such as nuclear factor-kappa B (NF-κB), tumor necrosis factor-alpha (TNF-α), interleukin-one beta (IL-1ß), were measured in removed lung tissues. Tissues were also examined histopathologically. Biochemical results showed that ULEtOAc significantly suppressed the increase of MDA, NF-κB, TNF-α, and IL-1ß levels and the decrease of tGSH caused by S. aureus in lung tissue. S. aureus inoculation caused severe mononuclear cell infiltration in interstitial areas, severe lymphoid hyperplasia in bronchial-associated lymphoid tissue and severe alveolar edema, histopathologically. Treatment with ULEtOAc had an attenuating effect on these histopathological findings. Experimental results from this study suggest that ULEtOAc may be beneficial in treating S. aureus-induced oxidative and inflammatory lung damage.

The Role of Adrenaline, Noradrenaline, and Cortisol in the Pathogenesis of the Analgesic Potency, Duration, and Neurotoxic Effect of Meperidine.

Background and Objectives: The purpose of the study was to investigate the role of adrenaline (ADR), noradrenaline (NDR), and cortisol in the pathogenesis of the analgesic potency, duration, and epilepsy-like toxic effect of meperidine. Materials and Methods: The experimental animals were separated into 11 groups of six rats. In the meperidine (MPD) and metyrosine + meperidine (MMPD) groups, paw pain thresholds were measured before and after the treatment between the first and sixth hours (one hour apart). In addition, ADR and NDR analyses were performed before and after the treatment, between the first and fourth hours (one hour apart). For the epilepsy experiment, caffeine, caffeine + meperidine, and caffeine + meperidine + metyrapone groups were created, and the treatment was applied for 1 day or 7 days. Groups were created in which caffeine was used at both 150 mg/kg and 300 mg/kg. Epileptic seizures were observed in epilepsy groups, latent periods were determined, and serum cortisol levels were measured. Results: In the MPD group, pain thresholds increased only at the first and second hours compared to pre-treatment, while ADR increased at the third hour, leading to a decrease in pain thresholds. In the MMPD group, the increase in paw pain thresholds at 1 and 6 h was accompanied by a decrease in ADR and NDR. In the caffeine (150 mg/kg) + meperidine group, 1-day treatment did not cause epileptic seizures, while seizures were observed and cortisol levels increased in the group in which treatment continued for 7 days. When cortisol levels were compared between the group in which caffeine (300 mg/kg) + meperidine + metyrapone was used for 7 days and the animals receiving caffeine (300 mg/kg) + metyrapone for 7 days, it was found that cortisol levels decreased and the latent period decreased. Conclusions: The current study showed that if serum ADR and cortisol levels are kept at normal levels, a longer-lasting and stronger analgesic effect can be achieved with meperidine, and epileptic seizures can be prevented.

The role of Hippophae rhamnoides L. on 5-fluorouracil-induced oral mucositis in rats.

Current study aimed to research the effect of Hippophae rhamnoides (HRE) on potantial oral oxidative and inflammatory damage of 5-FU in rats. The rats were assigned to three groups; healthy (HG), 5-FU 100mg/kg (FUG) and HRE 50mg/kg +5-FU 100mg/kg (HRFU). The 5-FU was injected in the FUG group intraperitoneally. The HRFU was injected 5-FU at 100mg/kg IP one hour after the 50mg/kg HRE was given orally. Olive oil was used as a solvent for the HG. HRE was given to the rats three times a day for ten days. 5-FU was given one dose on the 1st, 3rd and 5th days. On the 10th day, the tissues removed from the animals were euthanized with high-dose anaesthesia and were macroscopically examined. The levels of the oxidant, antioxidant and proinflammatory cytokines were investigated.It was seen that HRE alleviated the symptoms of severe mucositis by antagonizing the effects of 5-FU on oxidant, antioxidant and proinflammatory cytokines such as malondialdehyde, total glutathione, superoxide dismutase, catalase, nuclear factor kappa-B and interleukin-6 in inner cheek and tongue tissue. These results recommend that HRE may be benefical in the cure of 5-FU-associated oral mucositis.

Effects of taxifolin on aspirin-induced gastric damage in rats: macroscopic and biochemical evaluation.

Taxifolin (dihydroquercetin) is a flavanonol isolated from various plants and has antioxidant effects. The aim of our study was to macroscopically and biochemically investigate the effects of taxifolin on aspirin-induced oxidative gastric damage in rats and to evaluate them by comparison with those of famotidine. Rats were divided into four drug administration groups: a healthy control group, an aspirin-only group (ASG), a taxifolin + aspirin group (TASG), and a famotidine + aspirin group (FASG). The results revealed that in light of the results that we obtained, 50 mg/kg taxifolin had anti-ulcer effects. At this dose, taxifolin was able to bring COX-1 activities to a level close to those seen in healthy rats with appropriate macroscopic, oxidant/antioxidant, and biochemical parameters. Based on these results, it can be said that taxifolin may be successfully used as a more potent alternative to famotidine, which is the currently accepted treatment for aspirin-induced ulcers.

Effect of felodipine on indomethacin-induced gastric ulcers in rats.

Felodipine is a calcium channel blocker with antioxidant and anti-inflammatory properties. Researchers have stated that oxidative stress and inflammation also play a role in the pathophysiology of gastric ulcers caused by nonsteroidal anti-inflammatory drugs. The aim of this study was to investigate the antiulcer effect of felodipine on indomethacin-induced gastric ulcers in Wistar rats and compare it with that of famotidine. The antiulcer activities of felodipine (5 mg/kg) and famotidine were investigated biochemically and macroscopically in animals treated with felodipine (5 mg/kg) and famotidine in combination with indomethacin. The results were compared with those of the healthy control group and the group administered indomethacin alone. It was observed that felodipine suppressed the indomethacin-induced malondialdehyde increase (P<0.001); reduced the decrease in total glutathione amount (P<0.001), reduced the decrease superoxide dismutase (P<0.001), and catalase activities (P<0.001); and significantly inhibited ulcers (P<0.001) at the tested dose compared with indomethacin alone. Felodipine at a dose of 5 mg/kg reduced the indomethacin-induced decrease in cyclooxygenase-1 activity (P<0.001) but did not cause a significant reduction in the decrease in cyclooxygenase-2 activity. The antiulcer efficacy of felodipine was demonstrated in this experimental model. These data suggest that felodipine may be useful in the treatment of nonsteroidal anti-inflammatory drug-induced gastric injury.

Tocilizumab is effective in preventing ovarian injury induced by ischemia- reperfusion in rats.

Ovarian torsion can be defined as the bending of the ovaries on the supporting ligament, disrupting both venous and arterial blood circulation. Insufficient blood flow causes ovarian tissue hypoxia and leads to ischemia. This study aimed to investigate whether tocilizumab has a protective effect on ischemia-reperfusion injury due to ovarian torsion in rats. Eighteen female Wistar albino rats were divided into three equal groups (Sham (SG), ischemia-reperfusion (OIR), and ischemia-reperfusion+tocilizumab (OIRT)). Degeneration, necrosis, vascular dilatation/congestion, interstitial edema, hemorrhage, and polymorphonuclear lymphocyte (PMNL) infiltration scores were significantly different between the groups (p=0.001 for all parameters). Moreover, the OIRT group had a significant improvement in these criteria compared to the OIR group (p<0.05). Additionally, there was a considerable difference between OIRT and OIR groups in the number of primordial, developing, and atretic follicles groups (p<0.05), while there was no difference in the number of corpus luteum (p=0.052). Stress markers or cytokines, such as MDA, tGSH, NF-κB, TNF-α, IL-1ß, and IL-6, were significantly different between groups (p<0.05). Furthermore, a significant improvement was found in the measured variables when the OIRT group was compared with the OIR group (p<0.05). Tocilizumab may be an alternative option for treating ischemia-reperfusion injury due to ovarian torsion.

The effects of metyrosine on ischemia-reperfusion-induced oxidative ovarian injury in rats: Biochemical and histopathological assessment.

The aim of this study is to investigate the effect of metyrosine on ischemia-reperfusion (I/R) induced ovarian injury in rats in terms of biochemistry and histopathology. Rats were divided into: ovarian I/R (OIR), ovarian I/R+50 mg/kg metyrosine (OIRM) and sham (SG) operations. OIRM group received 50 mg/kg metyrosine one hour before the application of the anesthetic agent, OIR and SG group rats received equal amount of distilled water to be used as a solvent orally through cannula. Following the application of the anesthetic agent, ovaries of OIRM and OIR group rats were subjected to ischemia and reperfusion, each of which took two hours. This biochemical experiment findings revealed high levels of malondialdehyde (MDA) and cyclo-oxygenase-2 (COX-2) and low levels of total glutathione (tGSH), superoxide dismutase (SOD) and cyclo-oxygenase-1 (COX-1) in the ovarian tissue of OIR group, with significant histopathological injury. In metyrosine group, MDA and COX-2 levels were lower than the OIR group whereas tGSH, SOD and COX-1 levels were higher, with slighter histopathological injury. Our experimental findings indicate that metyrosine inhibits oxidative and pro-inflammatory damage associated with ovarian I/R in rats. These findings suggest that metyrosine could be useful in the treatment of ovarian injury associated with I/R.

Effects of benidipine, paracetamol, and their combination on postoperative and normal tissue pain thresholds.

Introduction: In clinical practice, inadequate pain inhibition leads to increased morbidity and mortality. Increased intracellular calcium, oxidants, and proinflammatory cytokines are known to play a role in the pathogenesis of postoperative pain. Therefore, we investigated the analgesic effects of benidipine, paracetamol, and benidipine-paracetamol combination (BPC) on postoperative and normal pain thresholds in rats. Material and methods: Sixty-four male albino Wistar rats weighing 285-295 g were used. The without-incision rats were divided into 4 subgroups: healthy control, benidipine alone, paracetamol alone, and BPC. The scalpel-incision rats were divided into 4 subgroups: scalpel incision, scalpel incision + benidipine, scalpel incision + paracetamol, and scalpel incision + BPC. Paw pain thresholds of rats were measured using a Basile algesimeter. Biochemical analyses were performed on the paw tissues of 6 rats randomly taken from the experimental groups, each containing 8 rats. Rats were sacrificed immediately after the measurements. After the pain threshold tests were finished, the paw tissues were removed and malondialdehyde (MDA), total glutathione (tGSH), cyclooxygenase (COX), and interleukin-6 (IL-6) levels were measured. Results: There was no significant difference between the groups in paw pain threshold and measured biochemical parameters in rats without incision. The decrease in the pain threshold of the incised paw was also best prevented by BPC, followed by benidipine and then paracetamol. Furthermore, increases in scalpel-incised paw tissue MDA, COX-2, and IL-6 levels and the decrease in tGSH were significantly suppressed by benidipine and BPC, while paracetamol could only significantly inhibit the increase in IL-6 production. Conclusion: The combination of the L-type Ca2+ channel blocker benidipine and paracetamol (BPC) may provide potent analgesia. Our experimental results support that BPC may be useful in the treatment of severe pain that cannot be adequately inhibited by paracetamol.

The preventive effect of exogenous adenosine triphosphate on methanol-induced cardiotoxicity in rats

Abstract Exposure to methanol can cause serious consequences such as permanent visual disturbances and death. The heart tissue is highly vulnerable to ATP deficiency. Our study aimed to investigate whether exogenous ATP administration may alleviate methanol-induced ATP deficiency and subsequent oxidative damage in rat heart tissue. A total of 30 rats were divided into equal five groups; Healthy Group (HG), Methotrexate (MXG), Methanol (MeOH), Methotrexate+Methanol (MXM), and Methotrexate+Methanol+ATP (MMA) groups. We inhibited tetrahydrofolate synthesis by methotrexate to induce methanol toxicity. Methotrexate was administered to MXG, MXM, and MMA group animals for seven days with a catheter directly to the stomach at a 0,3 mg/kg dose per day. At the end of this period, % 20 methanol at a dose of 3 g/kg was administered to MeOH, MMA and MXM group animals. Immediately after methanol application, MMA group animals were injected with ATP at a 4 mg/kg dose intraperitoneally. Blood samples and heart tissues were used for biochemical analysis and histopathological examination. Co-exposure to methanol and methotrexate substantially exacerbated cardiac damage, indicating the potent cardiotoxic effects of methanol. However, the administration of exogenous ATP to MMA group animals brought biochemical oxidative damage parameters and histopathological findings closer to HG.

The effect of rutin on pulmonary contusion induced by blunt trauma in rats: Biochemical and histopathological evaluation.

Background: This study aims to investigate the possible protective effects of rutin, also called vitamin P1, against pulmonary contusion induced by blunt chest trauma in a rat model. Methods: Thirty male albino Wistar rats were separated into three equal groups as healthy group, trauma group, and trauma+rutin group. After anesthesia provided by intraperitoneal administration of 60 mg/kg ketamine and xylazine by inhalation at appropriate intervals, 200 g weight was dropped from 1 m height to the anterior chest wall of the animals in the trauma group (n=10) and trauma+rutin group (n=10) and pulmonary contusion was created. Thirty min after the trauma, 50 mg/kg of rutin was administered into the stomach of trauma+rutin group animals orally with gavage. The rats received rutin once daily for two days and were sacrificed 48 h later. Their lung tissues were removed and examined biochemically and histopathologically. Results: Nuclear factor-kappa B, cyclooxygenase-2, and malondialdehyde levels increased in the trauma group compared to the healthy group, and rutin administration prevented this increase. Total glutathione levels decreased in the trauma group, and rutin administration also prevented this decrease. The histopathological findings were compatible with the biochemical findings. Conclusion: Our study results suggest that rutin has a protective effect on contused lung tissue in rats.

Beneficial interaction of pycnogenol with indomethacin in rats.

Cyclooxygenase 2 (COX-2) is responsible for the therapeutic effects of indomethacin, while inhibition of the COX-1 enzyme and oxidative stress are responsible for its gastro-toxic effects. It has been reported that pycnogenol increases the expression of COX-1, suppresses the expression rate of COX-2 and oxidative stress. Our aim in this study is to investigate the antiinflammatory activities of indomethacin, pycnogenol, and their combination (PI) in rats and to examine their effects on stomach tissue. In the study, anti-inflammatory activity was investigated in carrageenan-induced inflammatory paw edema in albino Wistar male rats. Effects on stomach tissue were performed by applying the previous method. PI, indomethacin and pycnogenol were the best suppressors of carrageenan inflammation and oxidative stress in paw tissue, respectively. While the groups with the lowest COX-1 activity in paw tissue were IC, PIC and PC, respectively, PIC, IC and PC were the ones that best inhibited the increase in COX-2 activity. Pycnogenol inhibited the increase of malondialdehyde, the decrease of total glutathione and COX-1 in the stomach, and significantly suppressed the formation of indomethacin ulcers. Our experimental results showed that pycnogenol reduced the toxic effect of indomethacin on the stomach and increased anti-inflammatory activity. This beneficial interaction of pycnogenol and indomethacin suggests that PI will provide superior success in the treatment of inflammatory diseases.

The effect of taxifolin on oxidative sciatic nerve damage induced by cobalt chloride in rats: a biochemical and histopathological evaluation.

Cobalt is a trace element that increases lipid peroxidation and malondialdehyde levels and reduces the antioxidant defense mechanisms of nerve cells. High levels of cobalt exposure may cause peripheral neuropathy, but the mechanism behind this has not yet been elucidated. Taxifolin is a flavonoid whose antioxidant and anti­inflammatory properties are well­known. We aimed to investigate the effect of taxifolin on cobalt­induced oxidative sciatic nerve damage. Eighteen albino male Wistar rats were assigned to three groups: Control, Cobalt, and Taxifolin + Cobalt groups. Total oxidant and total antioxidant status and levels of malondialdehyde, total glutathione, and superoxide dismutase were measured to determine the effect of taxifolin on cobalt­induced sciatic nerve injury. The following statistically significant effect of taxifolin was observed: It prevented cobalt­induced oxidative sciatic nerve damage by reducing malondialdehyde levels and total oxidant status and increasing total antioxidant status, total glutathione levels, and superoxide dismutase levels. In a histopathological analysis, we observed similar findings in Control and Taxifolin + Cobalt groups. We determined that taxifolin is effective in preventing cobalt­induced oxidative damage in sciatic nerve injury.

Can pycnogenol prevent cisplatin-induced damage in uterus and ovaries?

Introduction: Cisplatin is an antineoplastic agent, which is thought to act on tissues with increased levels of reactive oxygen species and decreased levels of antioxidants. Pycnogenol is a potent antioxidant that is used in medical conditions caused by oxidative stress. The aim of our study is to demonstrate the effects of pycnogenol on cisplatin-induced uterine and ovarian damage in rats. Material and methods: Wistar albino female rats were randomly divided into 3 groups before the experiment as follows: a 2.5 mg/kg cisplatin group (CG; n = 10), a 40 mg/kg pycnogenol + 2.5 mg/kg cisplatin group (PCG; n = 10), and a healthy control group (HG; n = 10). Then, the ovaries and uteri of the rats were examined to determine malondialdehyde (MDA), total glutathione (tGSH) and superoxide dismutase (SOD) biochemical levels and the histopathological findings. Results: Our study demonstrated that, in uterine and ovarian tissues of rats administered with cisplatin, there was a decrease in the levels of tGSH and SOD, while MDA was increased; however, it was observed that these ratios were reversed in the PCG group (p < 0.05). The number of follicles in the ovarian tissues was examined in all 3 groups. When the CG group was compared with the other two groups, the number of primordial, developing and atretic follicles was low, but there was no difference in the corpus luteum count. Conclusions: Pycnogenol pretreatment alleviates cisplatin-induced uterine and ovarian injury in rats because of its antioxidative effect.

Effect of taxifolin on methotrexate-induced oxidative and inflammatory oral mucositis in rats: biochemical and histopathological evaluation.

BACKGROUND: The role of oxidative stress, as well as inflammation in the pathogenesis of methotrexate (MTX)-induced oral mucositis, is a known fact. The anti-inflammatory, antitumor, antimicrobial, and antioxidant properties of taxifolin-the effect we tested against MTX-induced oral mucosal damage-are well known. OBJECTIVE: Evaluating biochemically and histopathologically the effects of taxifolin on methotrexate-induced oral mucosal damage in rats. METHODOLOGY: In the taxifolin+MTX (TMTX) group, 50 mg/kg taxifolin was orally administered to rats by gavage. In the MTX and healthy (HG) groups, normal saline was applied to rats as solvent by the same method. One hour after administration of taxifolin and solvent, 5 mg/kg MTX was orally administered to rats in the MTX and TMTX groups. Taxifolin and methotrexate were administered once a day for 30 days. Macroscopic, biochemical, and histopathological evaluations were performed on the inner cheek and tongue tissues of rats. These parts were removed after rats were killed with a high-dose anesthesia. RESULTS: Taxifolin with MTX prevented the increase in oxidant and pro-inflammatory parameters, such as malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1ß), interleukin 6 (IL-6), on the inner cheek and tongue tissues of rats. Moreover, taxifolin antagonized the decrease in total glutathione (tGSH). Taxifolin decreased MTX-induced histopathological damage. CONCLUSION: These findings suggest that taxifolin may be useful to treat MTX-associated oral mucositis.

The protective effect of carvacrol on bevacizumab-related skin injury in rats: a biochemical and histopathological evaluation.

PURPOSE: Bevacizumab is a recombinant humanized monoclonal antibody that specifically binds to vascular endothelial growth factor (VEGF). Cutaneous side effects of bevacizumab are seen with substantial frequency and may require the interruption of the treatment. The aim of the study was to conduct a biochemical and histopathological investigation of the effects of carvacrol against the possible oxidative skin damage caused by bevacizumab in rats. MATERIALS AND METHODS: A total of 18 adult male Wistar albino rats were randomly assigned to three groups as healthy (H group; n = 6), bevacizumab alone (B group; n = 6), and carvacrol + bevacizumab (CB group; n = 6). Carvacrol was injected intraperitoneally (IP) at a dose of 50 mg/kg in the CB group. Sterile salt solution (0.9% NaCl) was used as a solvent for the H and B groups. One hour after the administration of carvacrol and solvent, bevacizumab at a dose of 10 mg/kg IP was administered to the CB and B groups. Bevacizumab was given once daily for a total of two doses, 15 days apart. Carvacrol was administered once daily for one month. After that period, all animals were sacrificed and their skin tissues removed. Malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPO), catalase (CAT), superoxide dismutase (SOD), total oxidant status (TOS), and total antioxidant status (TAS) levels in rats' skin tissues were biochemically evaluated. The parameters were measured with spectrophotometric method by using a microplate reader (BioTek, Winooski, VT, USA). The skin tissues were also examined histopathologically by the pathologist (blind) for the study groups. RESULTS: The MDA and TOS levels of the H and CB groups were significantly lower than the B group (p < 0.05). The mean scores of the other biochemical levels (GSH, GPO, CAT, SOD, TAS) in the H group were significantly higher than in the B and CB groups. Pathological examination of H group was normal. In B group epidermal atrophy, abnormal keratin accumulation, degenerated hair follicles, edoema and inflammatory cells accumulation in the dermis were observed. In the CB group, these findings were significantly improved. CONCLUSION: The positive effect of carvacrol against possible local oxidative skin damage due to bevacizumab in rats was demonstrated. In addition, more detailed studies are required to clarify the mechanism of the protective effect of carvacrol against bevacizumab-induced skin toxicity. The effect should be evaluated through further human studies, as well as studies using different doses of carvacrol.

The effect of rutin on experimentally induced acute heart contusion in rats: Biochemical and histopathological evaluation.

BACKGROUND: Acute cardiac contusion induced by trauma is known with its high mortality and morbidity. The role of oxidative stress and inflammation in its pathophysiology has led to the investigation of antioxidant and anti-inflammatory substances in non-sur-gical treatment. In this study, the effects of rutin which has these two features on acute cardiac contusion were investigated. METHODS: Thirty male albino Wistar rats were divided into three equal groups as healthy (HG), contusion (CG), and rutin + con-tusion (rutin + CG). A heart contusion was created dropping 200 g weight from 1-m height onto anterior thorax of CG (n=10) and Rutin + CG (n=10) group animals by anesthetizing with intraperitoneal administration of 60 mg/kg ketamine and xylazine inhalation at appropriate intervals. Thirty minutes after contusion was applied, rutin at the dose of 50 mg/kg was administered orally to the stomach by gavage to the rutin + CG group animals. The rutin was used once a day for 2 days. Rats were killed at the end of 48 h. Heart tissues were removed and examined biochemically and histopathologically. Troponin I (TP I) and creatine kinase-MB (CK-MB) were measured in blood samples taken from the tail veins just before the rats were killed. RESULTS: TP I, CK-MB, malondialdehyde, total oxidant status, and nuclear factor-kappa B levels increased in the CG when compared to the HG, and Rutin application prevented this increase, total glutathione (eGSH) and total antioxidant status levels decreased, and rutin application prevented this decrease. Histopathological findings also supported these findings. CONCLUSION: Rutin had a protective effect on heart tissue.

Effect of taxifolin on cyclophosphamide-induced oxidative and inflammatory bladder injury in rats.

The role of oxidative stress and inflammation in the pathogenesis of cyclophosphamide-related side effects has been demonstrated in previous studies. This study aimed to investigate the effect of taxifolin, due to its antioxidant and anti-inflammatory properties, on cyclophosphamide-induced oxidative and inflammatory bladder injury in albino Wistar rats. The taxifolin+cyclophosphamide (TCYC) group was given 50 mg/kg of taxifolin orally by gavage. Normal saline was used as a solvent for the cyclophosphamide (CYC) group and the healthy control (HC) group. One hour after taxifolin administration, 75 mg/kg of cyclophosphamide was intraperitoneally injected in the TCYC and CYC groups. This procedure was repeated once a day for 30 days. At the end of this period, biochemical markers were studied in the excised bladder tissues and histopathological evaluations were conducted. In the histopathological evaluation of the CYC group, severe epithelial irregularity, dilatation, congestion, and polymorphonuclear leukocyte accumulation in the vascular structures were observed. Additionally, the malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) levels, the total oxidant status (TOS), and the oxidative stress index (OSI) values were significantly higher, and the total glutathione (tGSH) levels and total antioxidant status (TAS) were significantly lower in the CYC group in comparison to the HC group (P<0.001). Taxifolin reduced the cyclophosphamide-induced increases in the MDA, TNF-α, IL-1ß, and IL-6 levels and the TOS and OSI values; it decreased the tGSH and TAS levels and reduced histopathological damage (P<0.001). Taxifolin may be useful in the treatment of cyclophosphamide-induced bladder damage.

Effect of taxifolin on methotrexate-induced oxidative and inflammatory oral mucositis in rats: biochemical and histopathological evaluation

Abstract The role of oxidative stress, as well as inflammation in the pathogenesis of methotrexate (MTX)-induced oral mucositis, is a known fact. The anti-inflammatory, antitumor, antimicrobial, and antioxidant properties of taxifolin—the effect we tested against MTX-induced oral mucosal damage—are well known. Objective Evaluating biochemically and histopathologically the effects of taxifolin on methotrexate-induced oral mucosal damage in rats. Methodology In the taxifolin+MTX (TMTX) group, 50 mg/kg taxifolin was orally administered to rats by gavage. In the MTX and healthy (HG) groups, normal saline was applied to rats as solvent by the same method. One hour after administration of taxifolin and solvent, 5 mg/kg MTX was orally administered to rats in the MTX and TMTX groups. Taxifolin and methotrexate were administered once a day for 30 days. Macroscopic, biochemical, and histopathological evaluations were performed on the inner cheek and tongue tissues of rats. These parts were removed after rats were killed with a high-dose anesthesia. Results Taxifolin with MTX prevented the increase in oxidant and pro-inflammatory parameters, such as malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), interleukin 6 (IL-6), on the inner cheek and tongue tissues of rats. Moreover, taxifolin antagonized the decrease in total glutathione (tGSH). Taxifolin decreased MTX-induced histopathological damage. Conclusion These findings suggest that taxifolin may be useful to treat MTX-associated oral mucositis.