Fabrication of Helix aspersa Extract Loaded Gradient Scaffold with an Integrated Architecture for Osteochondral Tissue Regeneration: Morphology, Structure, and In Vitro Bioactivity.

Regeneration of osteochondral tissue with its layered complex structure and limited self-repair capacity has come into prominence as an application area for biomaterial design. Thus, literature studies have aimed to design multilayered scaffolds using natural polymers to mimic its unique structure. In this study, fabricated scaffolds are composed of transition layers both chemically and morphologically to mimic the gradient structure of osteochondral tissue. The aim of this study is to produce gradient chitosan (CHI) scaffolds with bioactive snail (Helix aspersa) mucus (M) and slime (S) extract and investigate the structures regarding their physicochemical, mechanical, and morphological characteristics as well as in vitro cytocompatibility and bioactivity. Gradient scaffolds (CHI-M and CHI-S) were fabricated via a layer-by-layer freezing and lyophilization technique. Highly porous and continuous 3D structures were obtained and observed with SEM analysis. In addition, scaffolds were physically characterized with water uptake test, micro-CT, mechanical analysis (compression tests), and XRD analysis. In vitro bioactivity of scaffolds was investigated by co-culturing Saos-2 and SW1353 cells on each compartment of gradient scaffolds. Osteogenic activity of Saos-2 cells on extract loaded gradient scaffolds was investigated in terms of ALP secretion, osteocalcin (OC) production, and biomineralization. Chondrogenic bioactivity of SW1353 cells was investigated regarding COMP and GAG production and observed with Alcian Blue staining. Both mucus and slime incorporation in the chitosan matrix increased the osteogenic differentiation of Saos-2 and SW1353 cells in comparison to the pristine matrix. In addition, histological and immunohistological staining was performed to investigate ECM formation on gradient scaffolds. Both characterization and in vitro bioactivity results indicated that CHI-M and CHI-S scaffolds show potential for osteochondral tissue regeneration, mimicking the structure as well as enhancing physical characteristics and bioactivity.

Investigation of the Relationship between Colistin Resistance and Capsule Serotypes in Carbapenem Resistant Klebsiella pneumoniae Strains.

Carbapenem-resistant Klebsiella pneumoniae is associated with high morbidity and mortality, and capsule serotypes make treatment difficult. The aim of this study is to investigate the relationship between colistin resistance and capsule types in carbapenem-resistant K. pneumoniae isolates. In 2018- 2020, we conducted our study with 115 carbapenem-resistant K. pneumoniae strains diagnosed by matrix-mediated laser desorption ionization time-of-flight mass spectrometry method (MALDI-TOF MS; Bruker Daltonics, Germany). Colistin sensitivities were determined by using DxM MicroScan WalkAway System (Beckman Coulter, ABD) automated system and were then verified by liquid microdilution (MIC). Capsule serotypes were investigated by conventional polymerase chain reaction (PCR) method. Among the carbapenem resistant K. pneumoniae isolates, 42% (48) were resistant to colistin and 58% (67) were susceptible to colistin. In the K. pneumoniae isolates with colistin resistance 33% (16) K5, 13% (6) K2, 8% (4) K20 4% (2) K1 and 2% (1) K54 and K57 capsule serotypes were found, while in the K. pneumoniae isolates with colistin susceptible 12% (8) K5, 4% (3) K2, 3% (2) K20, 1.5% (1) K1 and K54 capsule serotypes were found. Serotype K5 was very frequent in isolates collected from patients with urinary tract diseases. The resistance profile data obtained from the present study can serve as an information base to understand the infection pattern prevailing in the hospital.

Bioactive snail mucus-slime extract loaded chitosan scaffolds for hard tissue regeneration: the effect of mucoadhesive and antibacterial extracts on physical characteristics and bioactivity of chitosan matrix.

Biobased extracts comprise various bioactive components and they are widely used in tissue engineering applications to increase bioactivity as well as physical characteristics of biomaterials. Among animal sources, garden snailHelix aspersahas come into prominence with its antibacterial and regenerative extracts and show potential in tissue regeneration. Thus, in this study, bioactiveH. aspersaextracts (slime, mucus) were loaded in chitosan (CHI) matrix to fabricate porous scaffolds for hard tissue regeneration. Physical, chemical properties, antimicrobial activity was determined as well asin vitrobioactivity for bone and cartilage regeneration. Mucus and slime incorporation enhanced mechanical properties and biodegradation rate of CHI matrix. Scanning electron microscopy images showed that the average pore size of the scaffolds decreased with higher extract content. Mucus and slime extracts showed antimicrobial effect on two bacterial strains.In vitrocytotoxicity, osteogenic and chondrogenic activity of the scaffolds were evaluated with Saos-2 and SW1353 cell lines in terms of Alkaline phosphatase activity, biomineralization, GAG, COMP and hydroxyproline content. Cell viability results showed that extracts had a proliferative effect on Saos-2 and SW1353 cells when compared to the control group. Mucus and slime extract loading increased osteogenic and chondrogenic activity. Thus, the bioactive extract loaded CHI scaffolds showed potential for bone and cartilage regeneration with enhanced physical properties andin vitrobioactivity.

Exercise increases leptin levels correlated with IGF-1 in hippocampus and prefrontal cortex of adolescent male and female rats.

It is known that regular aerobic exercise has positive effects on hippocampus and prefrontal cortex. We have previously have been able to demonstrate that aerobic exercise increased IGF-1 in hippocampus. Leptin, which is associated with cognitive functions, is also involved in fat metabolism and stimulates energy consumption. While it is known that leptin stimulates IGF-1 production in hepatocytes, little known is on the link between IGF-1 and leptin in brain during aerobic exercise. In this study, we investigated the effects of regular aerobic exercise on leptin, leptin receptor expression levels in hippocampus and prefrontal cortex. Additionally, we investigated the correlation of IGF-1 levels with leptin and leptin receptor expression. During the experiment, exercise group was run on a treadmill for 30min per session at a speed of 8m/min and 0° slope, five times a week for 6 weeks. Leptin, leptin expression, IGF-1 levels and cell numbers increased in prefrontal cortex and hippocampus of exercise groups. Blood leptin levels increased in female rats in exercise group; whereas it did not change in male rats; blood IGF-1 levels were found to be increased in exercised male rats. There was a strong positive correlation between hippocampal leptin levels and hippocampal IGF-1 levels; also a strong positive correlation between hippocampal leptin receptor expression and hippocampal IGF-1. These results indicate that, increased leptin and leptin receptor expression are correlated with IGF-1 in regular aerobic exercised rats. Blood leptin and IGF-1 levels were also found to be associated with gender. Females had high blood leptin levels and males had high blood IGF-1 levels in the exercise groups.

Effects of administration of subtoxic doses of acetaminophen on liver and blood levels of insulin-like growth factor-1 in rats.

Acetaminophen (APAP) is widely used in the treatment of pain. Toxic doses of APAP cause acute liver failure, but therapeutic doses are believed to be safe. The purpose of this study is to investigate the effects of administration of subtoxic doses of APAP on liver and blood levels of insulin-like growth factor-1 (IGF-1) in rats. Low dose (100 mg/kg) and high dose (250 mg/kg) of APAP were intraperitoneally injected into Wistar albino rats. Following administration of therapeutic doses of APAP, there were no significant changes in serum transaminases and liver glutathione levels. Both doses of APAP induced a decrease in liver and blood levels of IGF-1 when compared with the controls. There was no significant difference in liver IGF-1 levels between the high-dose and low-dose APAP groups; however, there was a significant difference in blood IGF-1 levels between both the groups. The histological examination showed that low dose of APAP induced mild degree of structural change, while high dose of APAP induced severe structural damage. In conclusion, these results suggest that blood IGF-1 levels may have a value in predicting hepatic damage resulting from therapeutic doses of APAP.

Potential novel biomarkers for diabetic testicular damage in streptozotocin-induced diabetic rats: nerve growth factor Beta and vascular endothelial growth factor.

BACKGROUND: It is well known that diabetes mellitus may cause testicular damage. Vascular endothelial growth factor (VEGF) and nerve growth factor beta (NGF-ß) are important neurotrophic factors for male reproductive system. OBJECTIVE: We aimed to investigate the correlation between testicular damage and testicular VEGF and NGF-ß levels in diabetic rats. METHODS: Diabetes was induced by streptozotocin (STZ, 45 mg/kg/i.p.) in adult rats. Five weeks later testicular tissue was removed; testicular VEGF and NGF-ß levels were measured by ELISA. Testicular damage was detected by using hematoxylin and eosin staining and periodic acid-Schiff staining, and apoptosis was identified by terminal-deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL). Seminiferous tubular sperm formation was evaluated using Johnsen's score. RESULTS: In diabetic rats, seminiferous tubule diameter was found to be decreased; basement membrane was found to be thickened in seminiferous tubules and degenerated germ cells. Additionally, TUNEL-positive cells were increased in number of VEGF+ cells and levels of VEGF and NGF-ß were decreased in diabetic testes. Correlation between VEGF and NGF-ß levels was strong. CONCLUSION: These results suggest that the decrease of VEGF and NGF-ß levels is associated with the increase of the apoptosis and testicular damage in diabetic rats. Testis VEGF and NGF-ß levels could be potential novel biomarkers for diabetes induced testicular damage.

Positive effects of aerobic exercise on learning and memory functioning, which correlate with hippocampal IGF-1 increase in adolescent rats.

It is already known that regular aerobic exercise during adolescent period improves learning and memory in rats. In this study, we investigated the effects of regular aerobic exercise on learning, memory functioning and IGF-1 levels. IGF-1 is known to have positive effects on cognitive functions in adolescent rats. Exercise group was separated into two different groups. First half was run on a treadmill for 30 min per session at a speed of 8m/min and 0° slope, five times a week for 6 weeks. The second half was given free access to a running wheel (diameter 11.5 cm) which was connected to a digital counter and run on a treadmill for 6 weeks. Learning and memory functioning were found to be positively correlated with the exercise activity. Findings suggest increased neuron density in CA1 hippocampal region and dentate gyrus. Increased IGF-1 level was detected in hippocampus and blood serum, while IGF-1 level in liver tissue did not change with exercise activity. In conclusion, our findings indicate that learning and memory functioning were positively affected by voluntary and involuntary physical exercise which correlated increased hippocampal activity and elevated IGF-1 levels in adolescent rats.

Combined treatment with progesterone and magnesium sulfate positively affects traumatic brain injury in immature rats.

AIM: It is well known that head trauma results in damage in hippocampal and cortical areas of the brain and impairs cognitive functions. The aim of this study is to explore the neuroprotective effect of combination therapy with magnesium sulphate (MgSO4) and progesterone in the 7-days-old rat pups subjected to contusion injury. MATERIAL AND METHODS: Progesterone (8 mg/kg) and MgSO4 (150 mg/kg) were injected intraperitoneally immediately after induction of traumatic brain injury. Half of groups were evaluated 24 hours later, the remaining animals 3 weeks after trauma or sham surgery. Anxiety levels were assessed with open field activity and elevated plus maze; learning and memory performance were evaluated with Morris Water maze in postnatal 27 days. RESULTS: Combined therapy with progesterone and magnesium sulfate significantly attenuated trauma-induced neuronal death, increased brain VEGF levels and improved spatial memory deficits that appear later in life. Brain VEGF levels were higher in rats that received combined therapy compared to rats that received either medication alone. Moreover, rats that received combined therapy had reduced hipocampus and prefrontal cortex apoptosis in the acute period. CONCLUSION: These results demonstrate that combination of drugs with different mechanisms of action may be preferred in the treatment of head trauma.

Structural deteriorations of the human peritoneum during laparoscopic cholecystectomy. A transmission electron microscopic study.

BACKGROUND: In previous studies, changes in the surface of the peritoneum during laparoscopic surgery are well defined. Nevertheless, almost all of these studies were performed on rodents via scanning electron microscopy. In the present study, structural alterations of the mesothelial cells of peritoneum were examined during laparoscopic cholecystectomy using transmission electron microscopy. METHODS: Twenty patients with symptomatic cholelithiasis were included in the study. Peritoneal biopsy was performed immediately after CO2 pneumoperitoneum creation and at the end of surgery just before gallbladder removal. Biopsies were taken from the right upper quadrant, i.e., apart from operative manipulation. Peritoneal sample cross-sections were compared using transmission electron microscopy. RESULTS: The carbon dioxide pneumoperitoneum during laparoscopic cholecystectomy caused deteriorations of the peritoneal mesothelium. Apoptosis were developed in mesothelial cells. Bulging of mesothelial cells, irregular cell junctions, focal intercellular clefts, apical cell membrane degeneration, deep nuclear invaginations, and lipid droplets in the cytoplasm of the mesothelial cells were other remarkable findings. Mesothelial edema also was determined. DISCUSSION: As seen in previous studies, basement membrane nudity appeared after carbon dioxide pneumoperitoneum could be attributable to mesothelial cell apoptosis, deterioration of the cell structure, and cell organelles.

Serum IGF-1 levels correlate negatively to liver damage in diabetic rats.

Diabetes and insulin resistance frequently cause liver damage. Diabetes also causes reduction in liver and blood IGF-1 levels. We investigated the relation between liver damage and IGF-1 levels in diabetic rats. Fourteen Wistar albino rats were divided into control and diabetic groups. Diabetes was induced by streptozotocin. Rats were sacrificed for biochemical and histologic examinations 2 weeks after streptozotocin injection. Serum and liver IGF-1 levels were decreased, liver malondialdehyde (MDA) levels were increased, glutathione peroxidase (GPx) enzymes activities were decreased and serum alanine aminotransferase (ALT) levels were increased in diabetic group. Microscopic examination of liver revealed that normal tissue organization was disrupted in streptozotocin-induced diabetic rats. There was a strongly positive correlation between blood glucose levels and liver injury, and blood and liver IGF-1 levels. There was a strongly negative correlation between blood IGF-1 levels and hepatic injury. Our results suggest that reduction of blood IGF-1 levels correlates with hepatic injury and circulating IGF-1 levels may have predictive value for determining hepatic damage that results from diabetes. In addition, circulating IGF-1 levels are correlated with glutathione levels and the oxidative stress status of diabetic rat liver.

Preparation of (131)I-Pyrimethamine and evaluation for scintigraphy of experimentally Toxoplasma gondii-infected rats.

We aimed to assess the ability of (131)I-Pyrimethamine scintigraphy to detect the lesions of Toxoplasma gondii infection. An experimental model of toxoplasmosis was developed. The presence of toxoplasmosis was confirmed 60 days after implantation. Pyrimethamine was radioiodinated with I-131. The radioligand was validated by the requisite quality control tests to check its radiolabeling efficiency, in vitro stability and radiochemical purity etc. (131)I-Pyrimethamine (specific activity: 7.08 MBq/µmol) was injected intravenously into the tail vein of the control and infected rats. Static whole body images of the rats were acquired under the gamma camera at 5 min, 45 min, 2 h, 6 h, and 24 h following the intravenous administration of the radioactivity (3.7 MBq/rat). Then the scintigraphic data were analyzed both visually and semiquantitatively. Regions of interest (ROIs) were drawn over the organs (thyroid, stomach, liver, bladder, and soft tissues) to calculate the ratios of the radiotracer in infected vs. control rats. The mean ratio of radiotracer in infected/control rats in the liver and diaphragm was over 1 at 45 min which persisted till 24 h. In conclusion, (131)I-Pyrimethamine may be useful agent for diagnosis toxoplasmosis especially involving liver and diaphragm, needs further preclinical validation before being extended for use in clinical applications.

Anxiety correlates to decreased blood and prefrontal cortex IGF-1 levels in streptozotocin induced diabetes.

It is well known that diabetes mellitus may cause neuropsychiatric disorders such as anxiety disorders. Diabetes may also cause reduced IGF-1 (insulin like growth factor-1) levels in brain and blood. The purpose of the present study was to investigate the relationship between diabetes induced anxiety and IGF-1 levels in diabetic rats. The anxiety levels of rats were assessed 2 weeks after intraperitoneal injection of streptozotocin. Diabetic rats had higher levels of anxiety, as they spent more time in closed branches in elevated-plus-maze-test and less time in the center cells of open-field-arena. Prefrontal cortex (PFC) IGF-1 levels and neuron numbers were decreased and apoptosis was increased in diabetic rats. Blood IGF-1 levels decreased in a time dependent fashion following streptozotocin injection while blood corticosterone levels increased. They had higher malondialdehyde levels and lower superoxide dismutase enzyme activity. Oxidative stress may negatively affect blood and PFC tissue IGF-1 levels. Reduction in IGF-1 may cause PFC damage, which may eventually trigger anxiety in diabetic rats. Therapeutic strategies that increase blood and brain tissue IGF-1 levels may be promising to prevent psychiatric sequelae of diabetes mellitus.

Anxiety caused by traumatic brain injury correlates to decreased prefrontal cortex VEGF immunoreactivity and neuron density in immature rats.

AIM: Traumatic brain injury (TBI) may cause neuropsychiatric disorders such as anxiety disorder which has negative effects on cognitive functions and behavior. The aim of this study is to investigate the effects of TBI on anxiety and vascular endothelial growth factor (VEGF) immunoreactivity on the prefrontal cortex of immature rats, which is one of the anxiety-related regions of the brain in 7-day-old immature rats subjected to contusion injury. MATERIAL and METHODS: Rats were divided into three groups: Control (n=7), Sham (n=7) and TBI (n=7). Anxiety levels were assessed with open field activity and elevated plus maze in postnatal 27 days. Prefrontal cortex damage related to TBI was examined by cresyl violet staining and VEGF immunostaining. Prefrontal cortex neuronal density was calculated. Serum corticosterone levels were determined. RESULTS: The anxiety level in the TBI group was significantly greater than the control and sham groups. The prefrontal cortex VEGF immunostaining score and neuron density were decreased in the TBI group compared to control and sham group. Serum corticosterone levels were significantly increased in the TBI group. CONCLUSION: These results indicate that TBI decreases VEGF immunoreactivity in prefrontal cortex neurons and increases the anxiety levels of immature rats.

Maternal treadmill exercise during pregnancy decreases anxiety and increases prefrontal cortex VEGF and BDNF levels of rat pups in early and late periods of life.

In a previous study we demonstrated that, regular aerobic exercise during pregnancy decreased maternal deprivation induced anxiety. The purpose of this study is to investigate whether the positive effects of maternal exercise on the male and female offspring's early and late period of life. Half of the test subjects in each group were evaluated when they were 26 days old, and the other half were evaluated when they were 4 months old. The anxiety levels of maternally exercised groups were less than the control groups in both sexes and in both prepubertal and adult periods. The locomotor activity more increased in females. The prefrontal VEGF and BDNF levels were greater for both age groups and sexes in the maternally exercised group compared to control group. Moreover, there was a strong positive correlations between prefrontal cortex BDNF levels and results of open field tests; and VEGF levels and results of elevated plus maze tests. There was no difference in serum corticosterone levels between groups. These results indicate that maternal exercise during pregnancy may protect the pups from anxiety in early and late periods of life, and affects the prefrontal cortex positively.

Acute footshock-stress increases spatial learning-memory and correlates to increased hippocampal BDNF and VEGF and cell numbers in adolescent male and female rats.

It is well known that the acute-stress enhances cognitive functions in adults, but is not known in adolescents. The purpose of this study is to investigate the effects of low and high intensities of acute-stress on hippocampus and spatial memory in the adolescent male and female rats. Thirty-eight days aged rats were subjected to 0.2 and 1.6 mA intensity of footshock-stress for 20 min. Spatial memory performance was assessed in the Morris water maze. Learning had been positively affected in stress groups. Neuron density in the CA1 hippocampal region and the gyrus dentatus as well as VEGF and BDNF levels of hippocampus increased in all stress groups. In females, learning process and BDNF levels increased in low-intensity-stress group than high-intensity-stress group. There was no difference in hippocampal apoptosis among groups. We conclude that adolescent hippocampus is affected positively from acute-stress; however, while there is no difference in male response with respect to intensity of stress, females are affected more positively from low-intensity of stress.

Neuroprotective effects of recombinant human erythropoietin in the developing brain of rat after lithium-pilocarpine induced status epilepticus.

Status epilepticus triggers a mixture of apoptotic and necrotic cell death within the hippocampus. This neuronal loss may result in the development of epilepsy and cognitive deficits. Erythropoietin mediates a number of biological actions within the central nervous system and has been shown to be neuroprotective. In the present study, we investigated the effects of recombinant human erythropoietin on hippocampus of rat after lithium-pilocarpine induced status epilepticus. Twenty-one dam reared Wistar male rats, 21-day-old were divided into three groups: control group, lithium-pilocarpine induced status epilepticus and lithium-pilocarpine induced status epilepticus and erythropoietin treated group. Erythropoietin treated group received recombinant human erythropoietin 10 U/g intraperitoneally 40 min after pilocarpine injection for 5 days. Rats were sacrificed and brain tissues were collected at 5th day of experiment. Neuronal cell death and apoptosis were evaluated. Histopathological examination showed that erythropoietin significantly decreased neuronal cell death in CA1, CA2, CA3 and dentate gyrus regions of hippocampus. It also diminished apoptosis in the CA1 and dentate gyrus regions of hippocampus. In conclusion, erythropoietin may preserve the number of neurons and decrease apoptosis in model of status epilepticus induced by lithium-pilocarpine. This experimental study suggests that erythropoietin administration may be neuroprotective in status epilepticus.

Relationship between circulating IGF-1 levels and traumatic brain injury-induced hippocampal damage and cognitive dysfunction in immature rats.

It is well known that traumatic brain injury (TBI) induces the cognitive dysfunction resulting from hippocampal damage. In the present study, we aimed to assess whether the circulating IGF-I levels are associated with cognition and hippocampal damage in 7-day-old rat pups subjected to contusion injury. Hippocampal damage was examined by cresyl violet staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Spatial memory performance was assessed in the Morris water maze. Serum IGF-1 levels decreased in both early and late period of TBI. Decreased levels of serum IGF-1 were correlated with hippocampal neuron loss and spatial memory deficits. Circulating IGF-1 levels may be predictive of cognitive dysfunction resulted from hippocampal damage following traumatic injury in developing brain. Therapy strategies that increase circulating IGF-1 may be highly promising for preventing the unfavorable outcomes of traumatic damage in young children.

Carnosine attenuates oxidative stress and apoptosis in transient cerebral ischemia in rats.

Cerebral ischemia leads to cognitive decline and neuronal damage in the hippocampus. Reactive oxygen species (ROS) play an important role in the neuronal loss after cerebral ischemia and reperfusion injury. Carnosine has both antioxidant and neuroprotective effects against ROS. In the present study, the effects of carnosine on oxidative stress, apoptotic neuronal cell death and spatial memory following transient cerebral ischemia in rats were investigated. Transient ischemia was induced by occlusion of right common carotid artery of rats for 30 min and reperfusion for 24 h or 1 week. Rats received intraperitoneal injection of 250 mg/kg carnosine or saline 30 min prior to experiment. Determination of antioxidant enzyme activities was performed spectrophotometrically. To detect apoptotic cells, TUNEL staining was performed using an In Situ Cell Death Detection Kit. Carnosine treatment elicited a significant decrease in lipid peroxidation and increase in antioxidant enzyme activities in ischemic rat brains. The number of TUNEL-positive cells was decreased significantly in carnosine-treated group when compared with the ischemia-induction group. Carnosine treatment did not provide significant protection from ischemia induced deficits in spatial learning. The results show that carnosine is effective as a prophylactic treatment for brain tissue when it is administered before ischemia without affecting spatial memory.

The protective effects of carnosine and melatonin in ischemia-reperfusion injury in the rat liver.

The reperfusion following liver ischemia results in hepatocyte damage and apoptosis. The aim of this study was to investigate the effects of two antioxidant agents, carnosine and melatonin, in rat liver ischemia-reperfusion injury. Five study groups were formed; I. sham, II. ischemia-reperfusion, III. ischemia-reperfusion+melatonin, IV. ischemia-reperfusion+carnosine, V. ischemia-reperfusion+melatonin+carnosine. Then 250 mg/kg carnosine and 10 mg/kg melatonin were administered intraperitoneally 30 min before ischemia and immediately after the reperfusion. Sinusoidal dilatation, congestion and neutrophil infiltration were observed in the ischemia-reperfusion group while these symptoms were less pronounced in the treatment groups. Alanine aminotransferase, aspartate aminotransferase and myeloperoxidase levels were increased in the ischemia-reperfusion group while they were lowered in the treatment groups. Glutathione level was low in the ischemia-reperfusion group while it tended to increase in the ischemia-reperfusion+carnosine administered and ischemia-reperfusion+carnosine+melatonin administered groups. There was an increase in the number of apoptotic cells in the ischemia-reperfusion group while this number was lowered in the treatment groups. Carnosine was more effective than melatonin in the reversal of structural and biochemical alterations that resulted from ischemia-reperfusion injury. The administration of melatonin and carnosine together yielded better outcomes compared to the sole administration of each agent.