جستجوی مقالات مرتبط با کلیدواژه « Rat » در نشریات گروه « پزشکی »

 Here, we aimed to study the distribution pattern of normal and cancer xenogeneic exosomes (Exos) and possible interspecies reactions in a rat model.

 Exos were isolated from normal Human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 breast cancer cells. Diameter size and zeta potential distribution were studied using dynamic light scattering (DLS). The morphology of isolated Exos was monitored by scanning electron microscopy (SEM) images. Using western blotting, protein levels of exosomal tetraspanins were detected. For the in vivo study, Dil-labeled normal and cancer Exos were injected into the tail vein (100 µg exosomal protein/rat) three times at 1-hour intervals. After 24 hours, rats were euthanized and the cellular uptake of Exos was monitored in different organs using immunofluorescence staining (IF).

 The size distribution and mean zeta potential of HUVEC and MDA-MB-231 cells Exos were 80±29.94 and 64.77±25.49 nm, and −7.58 and −11.8 mV, respectively. Western blotting revealed CD9, CD81, and CD63 in normal and cancer Exos. The SEM images exhibited typical nano-sized round-shape Exo particles. IF staining indicated sequestration of administrated Exos in splenic tissue and lungs. The distribution of Exo in kidneys, aorta, and hepatic tissue was less. These features were more evident in the group that received cancer Exos. We found no obvious adverse effects in rats that received normal or cancer Exos.

 Normal and cancerous xenogeneic human Exos can be sequestrated prominently in splenic tissue and lungs. Novel delivery approaches and engineering tools are helpful in the target delivery of administrated Exos to the injured sites.

 Doxorubicin is a widely used antineoplastic agent for the treatment of solid tumors but its use is limited by its several severe tissue and organ toxicities. This study investigated changes in liver and spleen as a result of toxicity produced by Doxorubicin and the protective role of aqueous leaf extract of J. Tanjorensis.

In this experimental study, rats were divided into 5 groups as follows: Group 1 served as control and orally received normal saline once daily. Doxorubicin (15 mg/kg) was administered to Group 2  from day 10. Group 3 received J. Tanjorensis (300 mg/kg, orally) once daily for 12 days. Group 4 received J. Tanjorensis (300 mg/kg, orally) once daily for 12 days and Doxorubicin (15 mg/kg) from day 10. Group 5 received Vitamin C (100 mg/kg, orally) once daily for 12 days, and Doxorubicin (15 mg/kg) from day 10. Doxorubicin administration was done intraperitoneally for three consecutive days. Sera samples were collected and used to assess liver function enzymes and synthetic molecules. Liver and spleen tissues were used to examine histopathological analysis. Data were analyzed by SPSS v.20 at a significance level of P<0.05.  

 Administration of Doxorubicin caused significant increase in Alanine Transaminase (ALT), Aspartate Transaminase (AST), Acid Phosphatase (ACP), and total bilirubin (P values below 0.05), and a significant decrease in total protein and albumin compared to the control and J. Tanjorensis administered rats (P values below 0.05). The histopathological evaluation of liver tissue in the Doxorubicin injected rats revealed congestion, hemorrhagic necrosis, sinusoidal dilation, and mononuclear cell infiltration. Similarly, histology of spleen tissue in Doxorubicin administered rats showed degeneration and congestion, disintegrated peri-arteriolar lymphoid sheath, granuloma formation, and necrosis of lymphoid follicles. However, liver and spleen of rats given Doxorubicin and J. Tanjorensis showed reversal of liver function enzymes and synthetic ability towards normalcy, reduced signs of damage as well as recovering peri-arteriolar lymphoid sheath.

 Our study found that J. Tanjorensis is effective in preventing liver and spleen damage caused by Doxorubicin.

Clinical studies have consistently identified depression-related disorders as the most prevalent neuropsychiatric symptoms in Alzheimer's disease (AD). Quercetin has garnered significant attention as a therapeutic approach for various neuropsychiatric conditions, particularly symptoms of depression in individuals. This study aimed to compare the neuroprotective effects of quercetin on depression-like behaviors and serum levels of anti-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and galectin (Gal)-3, in a rat model of AD.

Forty-eight Wistar rats were categorized into six groups: control, sham, AD, quercetin 10, quercetin 25, and quercetin 100 mg/kg body weight through gavage for 8 weeks. The rat model of AD was induced by intra-cerebroventricular administration of streptozotocin (STZ; 4 mg/rat, bilaterally). Depressive-like behaviors were assessed using the forced swimming test (FST), elevated plus maze (EPM), and open field test (OFT). Additionally, serum Gal-3 and TNF-α concentrations were measured.

STZ administration led to increased depression-related behaviors in OFT, EPM, and FST. Significant elevations in serum TNF-α, coupled with a decrease in Gal-3 concentrations in the hippocampus of AD rats, were observed. Remarkably, quercetin treatment reversed hippocampal cytokine concentrations in STZ-treated rats. Quercetin at the doses of 25 and 100 mg/kg significantly increased serum Gal-3 concentrations compared to other groups.

The antidepressant effects of quercetin may be linked to its capacity to reduce inflammation and increase Gal-3 levels.

Stress elicits physiological and neuroendocrine responses mediated by the hypothalamic-pituitary-adrenal (HPA) axis and lateral hypothalamus (LH). However, prolonged stress can dysregulate neuropeptide systems like orexin. This study investigated the effects of temporary and prolonged stress on HPA activity and orexin processing in the rat LH. 

Male Wistar rats were exposed to various stress repetitions. The stress paradigm is defined as short (acute; 1 day and mild; 3 days) and long (sub-chronic; 10 days and chronic; 21 days)-term 6 hr daily restraint stress. Plasma corticosterone (CORT) served as an index of HPA function. Expression of prepro-orexin and its processing enzymes prohormone convertases (PC) 1 and 2 was measured in LH tissues using semiquantitative RT-PCR. 

The plasma level of CORT was elevated following mild, sub-chronic, and chronic, but not acute stress versus unstressed controls. The expression of prepro-orexin was heightened following all stress exposures. However, PC1 increased and PC2 decreased only after prolonged stress. The PC1/PC2 ratio was also selectively augmented with sub-chronic and chronic stress, implying impaired orexin maturation.

Together, these data demonstrate that the HPA axis and lateral hypothalamic orexin system respond to stress based on stress repetition. Changes in orexin processing enzyme mRNA, exclusively after chronic stress, imply potential effects on peptide maturation, requiring confirmation of the orexin production at the protein level.

Kelussia odoratissima is involved in the treatment of kidney stones, irritation of the urinary tract and kidney and bladder cleansing. It is useful for gout patients and is used to treat kidney and ureteral stones. The aim of this study was to investigate the effect of Kelussia odoratissima on renal function tests in male rats.

In this study, 20 rats were randomly divided into one control group and three treatment groups (n=5 per group). The treatment groups received a 40, 80, and 120 mg/kg silver nanoparticles produced by the extracts of Kelussia, orally once a day for 6 days. After taking a blood sample, a kidney function test was performed. SPSS software version 21 was used for data collection, and the results were presented as mean and standard deviation (mean±SEM).

Oral administration of silver nanoparticles produced by Kelussia extracts at 80 mg/kg dose significantly reduced bilirubin and urea compared to the control group (P<0.05). The 120 mg/kg dose also significantly reduced urea compared to the control group (P<0.05). There was no significant effect on total protein, albumin and urea.

Silver nanoparticles produced by the Kelussia extracts did not show any negative effect on kidney function, but had some positive effect on waste removal.

Psychological stress impairs cognitive performance and affects mood states. This study compares the effect of four types of psychological stress (crowding, relocation, isolation, and restraint) on locomotor activity, learning, and memory, as well as anxiety-like behaviors performed by the open field, elevated plus maze, and passive avoidance tests.

Wistar rats were randomly assigned to different groups of crowding, relocation, isolation, and restraint stress, and control. The stress induction was administered for 21 consecutive days (6 h/day). To evaluate various types of behaviors, the open field, elevated plus maze, and passive avoidance tests were employed.

According to the PA test results, the latency to enter the darkroom decreased significantly in all stress groups, especially in the crowding and isolation stress groups. However, it had an inverse relationship with serum corticosterone (CORT) levels. The total dark stay time increased significantly in the restraint and crowding stress groups, and also particularly, in the isolation stress group. In the isolation stress group, the number of darkroom entries decreased significantly. All stress groups spent a significantly shorter time in the open arms of the EPM apparatus. Finally, the total distance traveled, in the open field test was significantly lower in all stress groups, particularly in the isolation stress group.

Crowding and social isolation were the two stress types that had the most adverse effect on cognitive performance, as they induced stress-driven anxiety-like behaviors, probably due to increased CORT secretion. A high or low population of social density may create a condition, in which the nervous system could not efficiently manage stress, particularly at chronic levels.

Previous studies have shown promising findings on effectiveness of noisy Galvanic Vestibular Stimulation (nGVS) in various cognitive disorders. The connections of the vestibular system with the hippocampus has been proven. Here we investigated the effect of vestibular galvanic stimulation on the improvement of spatial learning and memory of rats.

Twelve Wistar rats were randomly divided into control and nGVS groups. The nGVS group underwent 30-minute sessions of stimulation at sub-threshold levels for a duration of fourteen days. Following the intervention, both groups underwent assessments of cognitive indices through the Morris water maze task, hippocampal neuronal spike rate by Single-Unit Recording (SUR) and the concentrations of c-fos protein in the hippocampus were measured using ELISA device.

The nGVS group exhibited a significant difference compared to the control group in both the time taken to reach the target platform and the percentage of time spent in the goal quarter during the Morris water maze test. The nGVS treatment significantly enhanced spike rate of hippocampal dentate gyrus (p<0.01) compared to the control group. Additionally, c-fos protein concentrations were increased in the nGVS (5.833) than the control group (4.126), (p<0.001).

According to the obtained results, nGVS plays a role in improving spatial memory, and a longer duration of intervention is suggested to achieve more obvious improvement results.

Cholestasis is caused by a malfunction of the biliary liver system. Oxidative stress plays an essential role in the progression of cholestasis. This study aimed to investigate the antioxidant and hepatoprotective effects of ethanolic extract of Juniperus excelsa M. Bieb (JE) fruits on hepatic impairment induced by bile duct ligation (BDL) in rats.

Experimental approach: 

Forty male Wistar rats were randomly divided into 4 groups; sham control + vehicle (SC), BDL + vehicle (BDL), BDL + JE extract (BDL + JE), and SC + extract (SC + JE). One day after surgery, the animals were treated with vehicle or ethanolic extract of JE (500 mg/kg/day) for 7 days. Finally, the blood was taken for biochemical and oxidative stress analysis. Furthermore, the liver tissue of rats was removed for histological examination.

Treatment with the extract of JE decreased the ALP level, whereas it enhanced total protein content compared to the BDL group. Also, JE increased the activity of SOD and GPx, as well as FRAP content compared to the BDL group; while it did not significantly affect the levels of MDA and inflammation markers. However, JE could not improve BDL-induced histopathological alterations in hepatic tissue.

Conclusion and implication:

 This study demonstrated that JE may be useful as an adjuvant therapy by attenuating ALP activity, increasing serum total protein and FRAP content, as well as improving the antioxidant enzymes activity of SOD and GPx. However, further research is warranted to explore the other underlying mechanisms of action.

To evaluate the safety and histological findings of intravitreal injection of ketamine in rats.

Each rat received a total volume of 0.1 ml of ketamine 0.01 mol/L (5 rats as ketamine group) or a total of 0.1 ml of normal saline 0.9% (5 rats as control group) under general anesthesia in a sterile condition. A histology assessment was performed 1 month after the intravitreal injection.

Lens opacity, necrosis, and atrophy of retinal layers and optic disc were not seen in five specimens in the ketamine group and five in the normal saline group. There was no inflammation in the vitreous, retinal layers, choroid, optic disc, and optic nerve in both groups.

Intravitreal injection of ketamine in a special dose has no obvious adverse effect on diverse intraocular tissue.

Drugs are among the opioid-like compounds that lead to the development of emotional behaviors in humans and animals. One of the emotional behaviors is stress behavior caused by fear, which can be caused by opioid and quasi-opioid compounds. In this study, the effect of intraventricular injection of brain (I.C.V) agonist (morphine sulfate) and hair receptor antagonist (naloxone) on fear behavior in adult male Wistar rats was investigated.

In this study, pure harmalin was used as a hallucinogenic drug that causes hallucinations and fear in animals as a positive control and saline as a sham was used for comparative studies with groups treated with morphine sulfate and naloxone. In this study, stereotax machine was used for cannulation and injection of I.C.V and Elevated plus-maze machine was used for behavioral testing.

The values used to treat the experimental groups for morphine sulfate (0.5, 1, 2.5, 5, 7μg/rat) and naloxone (0.5, 1, 2μg/rat) were selected. The results of intraventricular injection of (1, 2.5, 5μg/rat) morphine in the brains of rats in the experimental group showed a significant difference in the occurrence of fear behavior compared to the positive control group with P <0.05.
While injection of values (0.5, 7μg/rat) did not show a significant difference with p <0.05 compared to the positive control group. Also, the results of intraventricular injection (I.C.V) of naloxone (1μg/rat) showed a significant difference with p <0.05 in the occurrence of fear behavior in comparison with the positive control group. While injection of values (0.5, 2.5μg/rat) did not show a significant difference with P <0.05 compared to the positive control group. In this study, I.C.V (50 μg / rat) injection of pure harmalin, which is considered as a positive control group, shows the percentage of entry into the open arm and also the percentage of retention time in the open arm.

In conclusion, none of the data used in the present study in the area has a uniform performance and this diversity can be considered as a result of various mechanisms that require more detailed studies.

Sepsis poses a significant threat to human life, rendering it a burdensome medical disease. Despite significant advancements, the current state of medical science still lacks a viable and efficacious cure. Costunolide (COST) is a multifaceted sesquiterpene lactone that exhibits a range of actions, including anti-inflammatory and antioxidant properties. We investigated the potential impacts of COST on a rat sepsis model caused by cecal ligation and puncture (CLP).

We created an experimental rat model with the following groups: SHAM, CLP, CLP+low dose COST, and CLP+high dose COST. Blood, kidney, and lung samples were collected. Inflammatory mediators such as interleukin-1beta (IL-1β), IL-6, tumor necrosis factor-alpha (TNF- α), and nuclear factor kappa-B (NF-κB) were investigated. In addition, we assessed oxidative stress by measuring 8-Hydroxydeoxyguanosine (8-OHdG) immunopositivity, MDA levels, glutathione (GSH), and superoxide dismutase (SOD) activity. Histopathological and immunohistochemical examinations backed up our findings.

Compared to the CLP group, the COST group showed a reduction in inflammatory and oxidative stress indicators. The expression of inflammatory mediators was suppressed by COST, and histological examinations revealed improvements in kidney and lung tissues in the treatment groups.

Our study highlights the preventive effects of COST against CLP-induced sepsis-related injury. Considering its beneficial effects against many diseases, COST is worthy as to be evaluated against sepsis.

This study aims to investigate the effect of pomegranate juice on kidney damage caused by lithium in rats.

Six groups of animals were studied, group one received neither lithium nor pomegranate juice, group two received only lithium, group three received only pomegranate juice, and groups four to six received both lithium and pomegranate juice at different doses. Kidney biomarkers were investigated as indicators of acute kidney failure.

Comparison between the studied groups regarding the amount of creatinine in the serum of rats showed a significant relationship between serum creatinine levels of rats in the group receiving lithium and the control group, and the group receiving lithium and those receiving pomegranate juice at a dose of 100 mg/kg. A significant relationship was observed in the study of serum urea amount in rats between the control group and the group receiving lithium, and the lithium group and the group receiving pomegranate juice at a dose of 100 mg/kg.

Conclusions:

 There was no significant difference between the groups when the amount of cystatin C in the serum of rats was compared. Pomegranate juice at 100 mg/kg and lithium (25mg/kg) led to a significant decrease in serum creatinine levels, which reduced kidney damage induced by lithium. Serum urea also decreased significantly, suggesting that pomegranate has anti-toxic effects on kidneys from lithium toxicity

Calcium phosphates, particularly hydroxyapatite, are the main inorganic compounds of vertebrate bone.In this study, nanohydroxyapatite was prepared using kombucha Symbiotic Culture of Bacteria and Yeast (SCOBY), and its effect was investigated on osteoporosis in ovariectomized rats.  Kombucha-nanohydroxyapatite was synthesized by adding phosphoric acid to the kambucha scoby. Characterization of the nanoparticle was performed through X-ray diffraction, X-ray fluorescence, and transmission electron microscopy techniques. Female rats were divided into 5 groups: control, ovariectomized groups, and three ovariectomized groups treated with concentrations of 25, 50, and 100 mg/kg of nanoparticles. At the end of the treatment period, the levels of calcium, phosphorus, parathyroid hormone, and activity of alkaline phosphatase were measured in the blood samples. Calcium and phosphorus levels were also measured in bone and liver. The bone was evaluated histopathologically. The synthesis of nanohydroxyapatite with particle size of 30 nm was confirmed through the use of X-ray diffraction (XRD) and TEM techniques. A significant increase in calcium and phosphorus levels in the femur bone was observed in the ovariectomized group, which received the highest nanoparticle concentration compared to the ovariectomized group. Parathyroid hormone and alkaline phosphatase activity inhibition were increased in ovariectomized rats following treatment with the highest nanoparticle concentration. In the mentioned group, bone trabeculae proliferation and increased lacuna-containing osteocytes were also observed. This study suggested that the highest concentration of kombucha-nanohydroxyapatite could be partially absorbed into bone tissues and recover the bone-destructive changes caused by ovariectomy, although additional experiments are needed for confirmation.