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.

Taxifolin as a novel therapeutic agent for epileptic seizures induced by caffeine-induced oxidative stress in rats.

BACKGROUND: Epilepsy is a severe neurological disease that results from excessive and/or synchronized neuronal activity in the brain, and oxidative stress plays a role in its pathogenesis. Taxifolin is a flavonoid that exhibits antioxidant activity. OBJECTIVES: To investigate the effects of taxifolin on caffeine-induced epileptic seizures in rats and reveal the role of antioxidant activity in antiepileptic therapy. MATERIAL AND METHODS: Forty rats were divided into 4 groups (n = 6/group): caffeine 300 mg/kg group (CG), taxifolin 50 mg/kg + caffeine 300 mg/kg group (TCG), 2 mg/kg diazepam + 300 mg/kg caffeine group (DCG), and a healthy group (HG). Taxifolin was given to the TCG, and diazepam was given to the DCG orally. One hour later, caffeine was injected intraperitoneally into the CG, TCG and DCG rats. The time between the caffeine injection and the contractions (the latency period) was determined. Animals were euthanized 1 h after caffeine injection, and brain tissues were biochemically examined for oxidants and antioxidants. RESULTS: Taxifolin and diazepam prolonged the latency period to a similar extent (p = 0.549), while taxifolin was more successful in preventing mortality. Taxifolin suppressed the caffeine-induced increase in myeloperoxidase, total oxidant status and oxidative stress index, and decreased total glutathione, superoxide dismutase and total antioxidant status more effectively than diazepam (p < 0.05). CONCLUSIONS: We showed the relationship between antioxidant activity and epilepsy treatment, and demonstrated that taxifolin may be useful for treating epilepsy.

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.

Effect of adenosine triphosphate on amiodarone-induced optic neuropathy in rats: biochemical and histopathological evaluation.

OBJECTIVE: This study aims to investigate possible preventive effect of ATP on optic nerve damage caused by amiodarone in rats. MATERIAL AND METHOD: Thirty albino male Wistar rats weighing between 265 and 278 g were used in the study. Before the experiment, the rats were housed at 22 °C in a 12-h light/dark cycle under appropriate condition. The rats were equally divided into five groups of six animals each: healthy group, 50 mg/kg amiodarone (AMD-50), 100 mg/kg amiodarone (AMD-100), 25 mg/kg ATP + 50 mg/kg amiodarone (ATAD-50), and 25 mg/kg ATP + 100 mg/kg amiodarone (ATAD-100). At the end of 14th day, the animals were sacrificed using cardiac puncture under deep thiopental anaesthesia, and optic nerve tissues were harvested to measure superoxide dismutase (SOD), total glutathione (tGSH), malondialdehyde (MDA), and catalase (CAT) levels. RESULTS: The MDA levels were found to be significantly higher in the AMD-50 and AMD-100 groups compared to the healthy group (p ˂ 0.001). There was also a significant difference between the AMD-50 and ATAD-50 groups, and between the AMD-100 and ATAD-100 groups regarding MDA levels (p ˂ 0.001). tGSH, SOD, and CAT levels were significantly lower in the AMD-50 and AMD-100 groups compared to the healthy group (p ˂ 0.001). ATP was found to partially inhibit amiodarone-induced optic neuropathy. CONCLUSION: The biochemical and histopathological results of this study demonstrated that amiodarone at high doses caused more severe optic neuropathy inducing oxidative damage, but ATP could relatively antagonise these negative effects on the optic nerve. Therefore, we believe that ATP may be beneficial in preventing amiodarone-induced optic neuropathy.

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.

Effects of taxifolin on tramadol-induced oxidative and inflammatory liver injury in rats: an experimental study.

In this experimental study we aimed to investigate the biochemical and histopathological effects of concomitantly administered taxifolin on tramadol-induced liver damage in rats. The rats were divided into three groups; control group (CG), tramadol alone (TRG), and taxifolin + tramadol given (TTRG) groups. Malondialdehyde (MDA), total glutathione (tGSH), total oxidant status (TOS), total antioxidant status (TAS), nuclear factor-kappa beta (NF-kB), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) levels were measured in liver tissues. Liver tissues were also examined histopathologically. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were determined in blood samples. In tissue analyses, determinants of oxidative stress and inflammation, all were significantly higher in the TRG group compared with the control and TTRG groups. In the TTRG group, all oxidative stress and inflammation markers were significantly lower than in the TRG group. In addition, there was not any significant difference between the control and TTRG groups regarding the TOS and TAS status. Serum liver enzymes were also significantly higher in the TRG group than in the other two groups. In histopathological examinations, the control group had a normal histological appearance. Degenerative-necrotic hepatocytes and hemorrhage, which were seen at a severe level in the TRG group, were found to be moderate in the treated TTRG group. In addition, mononuclear cell infiltrations were found to be severe in the TRG group and mild in the treated TTRG group. Finally it was concluded that Taxifolin alleviated the toxic effects of tramadol on the liver including the histopathological and biochemical changes as well as the oxidative damage.

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.

Carvacrol prevents acrylamide-induced oxidative and inflammatory liver damage and dysfunction in rats.

Background: Acrylamide causes hepatotoxicity with the effect of oxidative stress and inflammatory processes. Carvacrol is a monoterpenic phenol with antioxidant and anti-inflammatory properties. Aims: To determine the effects of carvacrol on oxidative liver injury induced by acrylamide administration in rats. Methods: Rats were divided into three groups of six animals each: healthy group acrylamide group (ACR), and acrylamide + carvacrol group (TACR). First, carvacrol (50 mg/kg) was administered intraperitoneally to the CACR group. One hour later, acrylamide (20 mg/kg) was given orally to the ACR and CACR groups. This procedure was performed for 30 days, after which the animals were sacrificed. The malondialdehyde (MDA) and total glutathione (tGSH) levels, total oxidant (TOS) and total antioxidant status (TAS), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß), and nuclear factor kappa b (NF-κB) were measured in the excised liver tissues. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were determined in blood serum samples. Liver tissues were also examined histopathologically. Results: In the ACR group, malondialdehyde, TOS, ALT, AST levels, and NF-κB, IL-1ß, and TNF-α levels were found to be high, and tGSH and total antioxidant status levels were low. In addition, diffuse degenerative changes and necrosis in hepatocytes, and moderate inflammation in the portal region were detected in the liver tissues of the ACR group. While carvacrol prevented the biochemical changes induced by acrylamide, it also alleviated the damage in the histological structure. Conclusion: Carvacrol may be used for liver damage caused by acrylamide.

Protective Effect of Adenosine Triphosphate against 5-Fluorouracil-Induced Oxidative Ovarian Damage in vivo.

OBJECTIVE: The aim of our study was to analyze the effect of ATP on possible ovarian damage of 5-FU in rats. METHODS: The animals were divided to three groups; healthy group (HG), 5-FU alone group (FUG) and ATP+5-FU administered group (AFU). The ATP 4 mg/kg was injected intraperitoneally (IP) into the AFU group. The same volume of saline (0.9% NaCl) as the solvent was administered intraperitoneally to the HG and FUG groups. One hour after administering ATP and solvent, 5-FU 100 mg/kg was injected intraperitoneally to the animals in the AFU and FUG groups. ATP was administered to the animals once a day for 10 days. On the 1st, 3rd and 5th days of 5-FU, one dose (total of 3 doses) was administered. On day 10, the animals were euthanasia with high-dose anaesthesia and ovarian tissues were removed. The removed ovaries were analyzed biochemically andhistopathological. RESULT: ATP significantly suppressed both the increase in MDA and IL-6 levels, and the decrease in tGSH, SOD and CAT levels. Treatment with ATP significantly suppressed the severe vacuolization and primordial follicle degeneration induced by 5-FU in our study. CONCLUSION: ATP was possible to be useful for the treatment of 5-FU-induced ovarian damage.

The effect of carvacrol on the proinflammatory cytokines, histology, and fertility outcome of cisplatin-related ovarian change in a rat model.

OBJECTIVE: In women, agents used in chemotherapy treatment have side effects such as accelerating follicular depletion and early menopause. Thus, cytotoxic treatments may cause various effects ranging from partial damage to the ovary to premature ovarian failure (POI) and infertility. This study aimed to investigate the protective effect of carvacrol on cisplatin (CIS)-induced reproductive toxicity in female rats. MATERIALS AND METHODS: The animals were divided to four groups; a healthy group (HG), administered only cisplatin 2.5 mg/kg (CIS); cisplatin 2.5 mg/kg + carvacrol mg/kg (CC-50), and cisplatin 2.5 mg/kg + carvacrol 100 mg/kg (CC-100). In this study, the CC-50 and CC-100 groups were injected with carvacrol at 50 and 100 mg/kg intraperitoneally (IP). The CIS and HG groupswere administered normal saline as a solvent in the same way. One hour afterwardthe CC-50 and CC-100 groups were injected with cisplatin at 2.5 mg/kg IP. This procedure was continued once a day for 14 days. At the end of this period, six rats from each group were euthanized with high-dose anaesthesia. Biochemical (oxidant-antioxidant and proinflammatory cytokines) and histopathological examinations were performed on the right ovarian tissue removed from the dead rats. The remaining (n = 6 in each group) animals were kept in the laboratory with mature male rats for two months for breeding. Rats that didn't give birth within two months were considered infertile. A one-way ANOVA test was used for the biochemical analysis, the a Kruskal Wallis test was used for the histopathological analysis. RESULTS: It has been observed that cisplatine causes oxidative stress and inflammatory damage in the ovarian tissue of animals and ultimately causes infertility due to this oxidative stress. While carvacrol significantly suppressed cisplatin-related oxidative stress in ovarian tissue at the 50 and 100 mg/kg doses, it could suppress proinflammatory cytokine increase only at thecytokine increase only at the 100 mg/kg dose. In addition, carvacrol significantly reduced the development of cisplatin-related infertility (from 0 to 83.3%) at a dose of 100 mg/kg. CONCLUSION: These findings suggest that carvacrol at high doses can reduce the harmful effects of cisplatin on the ovary and improve ovarian reserve in rats.

Molecular mechanism of the protective effect of adenosine triphosphate against paracetamol-induced liver toxicity in rats.

Toxic doses of paracetamol are also known to be close to therapeutic doses. This study aimed to biochemically investigate the protective effect of ATP against paracetamol-induced oxidative liver injury in rats and to examine the tissues histopathologically. We divided the animals into the paracetamol alone (PCT), ATP + paracetamol (PATP), and healthy control (HG) groups. Liver tissues were examined biochemically and histopathologically. Malondialdehyde level, AST and ALT activity in the PCT group were significantly higher than those in the HG and PATP groups (p < 0.001). The glutathione (tGSH) level, superoxide dismutase (SOD) and catalase (CAT) activity in the PCT group was significantly lower than that in the HG and PATP groups (p < 0.001), while animal SOD activity was significantly different between the PATP and HG groups (p < 0.001). The activity of CAT was almost the same. In the group treated with paracetamol alone, lipid deposition, necrosis, fibrosis, and grade 3 hydropic degeneration were observed. No histopathological damage was observed of the ATP-treated group, except for grade 2 edema. We discovered that ATP reduces the oxidative stress caused by paracetamol ingestion and protects against paracetamol-induced liver injury at the macroscopic and histological levels.

Favipiravir-induced inflammatory and hydropic degenerative liver injury in rats.

BACKGROUND: Favipiravir is very effective in the treatment of many viral infections, especially at high doses. It was used at such doses to treat coronavirus disease 2019 (COVID-19) during the pandemic. However, liver damage was reported in patients undergoing such treatment. OBJECTIVES: This study aimed to investigate the effects of low and high doses of favipiravir on the liver of rats, using biochemical and histopathological methods. MATERIAL AND METHODS: Wistar albino rats were allocated to one of 3 groups, namely a healthy group (HG), a 100 mg/kg favipiravir (FAV-100) group and a 400 mg/kg favipiravir (FAV-400) group. Favipiravir was administered orally at 100 mg/kg and 400 mg/kg doses to the FAV-100 (n = 6) and FAV-400 (n = 6) groups, respectively. Distilled water was administered orally (1 mL) using the same method to the HG (n = 6). This procedure was repeated twice a day for 1 week. At the end of this period, the animals were euthanized with a high dose of thiopental anesthesia (50 mg/kg) and their liver tissues were removed. RESULTS: Favipiravir caused an increase in malondialdehyde (MDA), nuclear factor kappa B (NF-κB) and interleukin 6 (IL-6) levels in the liver tissue, as well as elevated alanine aminotransaminase (ALT) and aspartate aminotransferase (AST) levels in the blood. Moreover, favipiravir caused a decrease in total glutathione (tGSH), superoxide dismutase (SOD) and catalase (CAT) levels. In addition, severe edema, lymphocyte infiltration and hydropic degeneration were observed in the liver tissue of the FAV-400. CONCLUSIONS: High-dose favipiravir caused more significant oxidative and inflammatory damage in the liver tissue of rats than low-dose favipiravir.

Effect of adenosine triphosphate on ribociclib-induced skin toxicity in rats.

PURPOSE: Ribociclib is a CDK4/6 inhibitor approved for the treatment of breast cancer; it inhibits the activity of CDK4/6 by competitively binding to adenosine 5'-triphosphate (ATP) binding sites. Although generally well-tolerated, ribociclib has been connected to a number of serious dermatologic complications. This study explored the effects of ATP on ribociclib-induced skin damage. MATERIALS AND METHODS: Using a rat model, ATP 25 mg/kg was injected intraperitoneally in the ATP + Ribociclib (ATR) group (n = 6). Distilled water as solvent was applied to the healthy control (HC) group (n = 6) and ribociclib (RCB) group (n = 6). One hour after ATP and solvent administration, ribociclib (200 mg/kg) suspension prepared in distilled water was administered to the stomach by gavage (ATR and RCB groups). This was repeated once a day for 15 d. After that period, biochemical markers were studied in the skin tissues and histopathological evaluations were conducted. RESULTS: In the histopathological evaluation of the RCB group, dermal necrosis, degeneration in hair follicles, and pycnosis in keratinocytes were observed. Only mild degeneration was observed in the ATR group; the HC group had a normal histological appearance. The malondialdehyde (MDA) values were significantly higher and the superoxide dismutase (SOD), catalase (CAT), and total glutathione (tGSH) levels were significantly lower in the RCB group in comparison to the HC group (p < .001). ATP reduced the ribociclib-induced increases in the MDA values and decreased the SOD, CAT, and tGSH levels in the ATR group (p < .001). CONCLUSION: ATP may be useful in the treatment of ribociclib-induced skin damage.

The effects of sugammadex on gastric ischemia-reperfusion injury in rats: Biochemical and histopathological evaluation.

The primary sources of reactive oxygen species (ROS) that cause ischemia-reperfusion (I/R) injuries are enzymes xanthine oxidase (XO) and nicotinamide adenine dinucleotide phosphate oxidases (NOXs) in the literature, whereby one of the main ROS producing cells via NOX activity are polymophonuclear leukocytes (PNL). Sugammadex, the effect of which we plan to research against gastric I/R damage, is a modified gamma-cyclodextrin that antagonizes the action of steroidal neuromuscular blocking drugs. Previous studies have reported that sugammadex inhibits PNL infiltration. However, it is unknown whether an inhibitory effect on XO is present. We aimed to biochemically and histopathologically investigate the effects of sugammadex on I/R-induced stomach damage in rats. The animals were divided into groups that underwent gastric ischemia-reperfusion (GIR), 4 mg/kg sugammadex + gastric ischemia-reperfusion (SGIR), and a sham operation group (SG). The effect of sugammadex was evaluated by measuring oxidant-antioxidant and PNL parameters. There was no significant difference in XO levels between the SGIR and GIR groups. In the SGIR group, sugammadex inhibited the increase in myeloperoxidase (MPO) and malondialdehyde (MDA) levels (p < 0.001). The amount of MDA and MPO in the SGIR group was similar as in the SG group. Sugammadex significantly suppressed the decrease in tGSH levels in the SGIR group (p < 0.001). The difference between tGSH levels in the SG and SGIR groups was slight. In the SGIR group, sugammadex significantly suppressed the increase in tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL1-ß) levels compared to the GIR group (p < 0.001). Additionally, sugammadex corrected histopathological modifications as much as sham group. In conclusion, sugammadex may be beneficial in preventing oxidative stress.

Protective effect of adenosine triphosphate and benidipine separately or together against cardiotoxicity caused by bevacizumab.

Bevacizumab is a recombinant humanized monoclonal antibody whose adverse effects include cardiotoxicity. We investigated whether using adenosine triphosphate (ATP) or benidipine either separately or together protects against cardiac damage induced by bevacizumab in rats. Forty Wistar albino male rats were allocated to five groups of eight: bevacizumab (Bv), ATP + bevacizumab (ABv), benidipine + bevacizumab (BBv), ATP + benidipine + bevacizumab (ABBv) and untreated controls. Rats in the ABv group were injected intraperitoneally (i.p.) with 2 mg/kg ATP. The BBv group was given 4 mg/kg benidipine by oral gavage. The ABBv group was injected i.p. with 2 mg/kg ATP and simultaneously administered 4 mg/kg benidipine orally. One hour after administration of ATP, benidipine or normal saline, the Bv, ABv, BBv and ABBv groups were injected i.p. with 10 mg/kg bevacizumab. Malondialdehyde (MDA) and total glutathione (tGSH) levels were measured in cardiac tissue, and troponin I (TP I) and creatine kinase MB (CK-MB) levels were measured in blood samples. Tissue samples were examined for histopathology. We found the lowest TP I, CK-MB and MDA levels and the highest tGSH level in the ABBv group; these results were similar to the control group. Nuclei of cardiomyocytes in the BV group were misshapen and shrunken, and myofibers were disrupted; we also observed eosinophilic degeneration and interstitial edema. Blood capillaries were dilated and congested. We observed amelioration of these findings in the ABBv group. We found that ATP and benidipine alone or in combination reduced cardiac damage associated with the use of bevacizumab. ATP + benidipine combined therapy produced the most favorable results.