Acid Rat Model Research Articles

Modulation of the Tumor Microenvironment by Ellagic Acid in Rat Model for Hepatocellular Carcinoma: A Potential Target against Hepatic Cancer Stem Cells.

The resistance to therapy and relapse in hepatocellular carcinoma (HCC) is highly attributed to hepatic cancer stem cells (HCSCs). HCSCs are under microenvironment control. This work aimed to assess the systemic effect of ellagic acid (EA) on the HCC microenvironment to decline HCSCs. Fifty Wistar rats were divided into six groups: negative control (CON), groups 2 and 3 for solvents (DMSO), and (OVO). Group 4 was administered EA only. The (HCC-M) group, utilized as an HCC model, administered CCL4 (0.5 mL/kg in OVO) 1:1 v/v, i.p) for 16 weeks. HCC-M rats were treated orally with EA (EA + HCC) 50 mg/kg bw for five weeks. Biochemical, morphological, histopathological, and immunohistochemical studies, and gene analysis using qRT-PCR were applied. Results revealed elevated liver injury biomarkers ALT, AST, ALP, and tumor biomarkers AFP and GGT, and marked nodularity of livers of HCC-M. EA effectively reduced the biomarkers and restored the altered structure of the livers. At the mRNA level, EA downregulated the expression of TGF-α, TGF-β, and VEGF, and restored p53 expression. This induced an increase in apoptotic cells immunostained with caspase3 and decreased the CD44 immunostained HCSCs. EA could modulate the tumor microenvironment in the HCC rat model and ultimately target the HCSCs.

Neuroprotective Efficacy of a Nanomicellar Complex of Carnosine and Lipoic Acid in a Rat Model of Rotenone-Induced Parkinson's Disease.

Oxidative stress, accompanied by mitochondrial dysfunction, is a key mechanism involved in the pathogenesis of Parkinson's disease (PD). Both carnosine and lipoic acid are potent antioxidants, the applicability of which in therapy is hindered by their limited bioavailability. This study aimed to evaluate the neuroprotective properties of a nanomicellar complex of carnosine and lipoic acid (CLA) in a rotenone-induced rat model of PD. Parkinsonism was induced via the administration of 2 mg/kg rotenone over the course of 18 days. Two doses of intraperitoneal CLA (25 mg/kg and 50 mg/kg) were administered alongside rotenone to assess its neuroprotective effect. At 25 mg/kg CLA decreased muscle rigidity and partially restored locomotor activity in animals that received rotenone. Furthermore, it caused an overall increase in brain tissue antioxidant activity, accompanied by a 19% increase in neuron density in the substantia nigra and increased dopamine levels in the striatum relative to animals that only received rotenone. Based on the acquired results, it may be concluded that CLA have neuroprotective properties and could potentially be beneficial in PD treatment when used in conjunction with the base therapy.

EVALUATION OF CHONDROPROTECTIVE EFFECTS OF HYALURONIC ACID IN A RAT MODEL OF OSTEOARTHRITIS

Objective: To evaluate the chondroprotective effects of hyaluronic acid in a rat model of osteoarthritis.
 Study Design: Laboratory based experimental study.
 Place and Duration of Study: Department of Pharmacology, Army Medical College, Rawalpindi, in alliance with National Institute of health, Islamabad and Department of Pathology, Army Medical College Rawalpindi, from Apr to Jun 2019.
 Methodology: Sixteen (16) rats of Sprague Dawley breed were procured in this study. Osteoarthritis was induced in right knee joint of rats by surgical resection of medial meniscus and anterior cruciate ligament. They were allocated into two (02) groups with eight (08) rats in both groups. Group-I was control group that was treated with 0.2 ml intra articular saline once weekly for four weeks. While group-II was treatment group that was intra particularly administered with 0.2ml hyaluronic acid once weekly for four weeks. One week after the last dosage, gait pattern of the animals was scored. Then animals were sacrificed and a part of proximal tibia was obtained for histopathologic analysis.
 Results: Mean gait score of control group and treatment group was 3.25 ± 0.707 and 1.00 ± 0.756 respectively with a statistically significant p-value of <0.001, while mean histopathological Modified Mankin score of control and treatment group was 11.5 ± 1.195 and 5.50 ± 1.195 respectively with a significant p-value of <0.001.
 Conclusion: Intra articular viscosupplementation of hyaluronic acid in rat model of osteoarthritis resulted in improved gait pattern and histopathology.

Antioxidant and anti-diabetic effects of caffeic acid in a rat model of diabetes

Purpose: To determine the antioxidant and anti-diabetic potential of a natural flavonoid, caffeic acid in a streptozotocin-induced diabetic rat model.Methods: Experimental diabetes was induced in Wistar rats using streptozotocin injection. Caffeic acid was administered orally on daily basis for 5 weeks. A glucometer was used to monitor fasting blood glucose levels. Insulin levels were estimated using enzyme-linked immunosorbent assay (ELISA). The antioxidant potential of caffeic acid was measured by determining the activities of superoxide dismutase (SOD) and catalase (CAT), and levels of reduced glutathione (GSH) in rat liver. Standard assays were performed to determine the lipid profile of the rats. Histopathological analysis was performed to determine differences in microscopic structures of pancreas among the different treatment groups.Results: Caffeic acid administration resulted in significant enhancement of serum insulin level, and decrease in blood glucose level of diabetic rat models (p < 0.05). Caffeic acid exerted antioxidant effects by significantly increasing GSH levels and activities of CAT and SOD (p < 0.05). Histologicalexamination of the pancreas depicted normal islet morphology under caffeic acid administration in diabetic rats.Conclusion: These results reveal the antioxidant potential and anti-diabetic effect of caffeic acid in a diabetic rat model and point towards the potential applicability of caffeic acid in the management of diabetes mellitus.
 Keywords: Diabetes mellitus, Streptozotocin, Caffeic acid, Phenolics, Anti-diabetic, Antioxidant

Magnesium supplementation ameliorates toxic effects of 2,4-dichlorophenoxyacetic acid in rat model.

2,4-Dichlorophenoxyacetic acid (2,4-D) is an extensively used herbicide in the field of agriculture, its ever-escalating use induces toxicity, health effects, and environmental impact. Oxidative stress plays a key role in pathogenesis of 2,4-D-induced liver and kidney damage. Magnesium (Mg) is a highly effective antioxidant agent in restoring oxidative damage by directly influencing the metabolic and physiological processes. Therefore, the present study aimed to evaluate Mg role in ameliorating the oxidative damages provoked by 2,4-D in rat model. Male Wistar rats (180-220 g) were distributed into four groups and treated intragastrically for 4 weeks. Group 1: control, group 2: 2,4-D (150 mg/kg body weight/day), group 3: simultaneously treated with 2,4-D (150 mg/kg body weight/day) and Mg supplement (50 mg/kg body weight/day), and group 4: Mg supplement (50 mg/kg body weight/day). Under experimental conditions, plasma hepatic and renal biomarkers, tissue oxidative status, and antioxidant enzymes activities were investigated. Results demonstrated that 2,4-D intoxication caused hepatic and renal impairments as indicated by the significantly increased (p < 0.001) alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, urea, creatinine, and blood urea nitrogen levels. In addition, 2,4-D caused a significant enhancement (p < 0.001) in the level of malondialdehyde as well as reduction (p < 0.001) of the superoxide dismutase, catalase, and glutathione reductase activities in both hepatic and renal tissues. Mg treatment prevented and reversed the toxic variations induced by 2,4-D. In general, these outcomes suggest that Mg may have antioxidant potential and ameliorative effects against 2,4-D provoking hepatic and renal toxicity in rat model.

Cadmium acts as a silent killer of liver by inducing oxidative stress and hepatocellular injury and a possible amelioration by vitamin B12 and folic acid in rat model

&lt;br/&gt;&lt;b&gt;Purpose:&lt;/b&gt; To investigate the involvement of oxidative stress in Cadmium (Cd) induced alteration in the functional status of the liver. And to assess the efficacy of folic acid and vitamin B12 in preventing Cd-induced damage in the same. &lt;br/&gt;&lt;b&gt;Materials and methods:&lt;/b&gt; The experiment was carried out for four weeks. For the experiment, 25 healthy male adult Wistar albino rats were randomly selected and were divided into five equal groups and treated as control, treated with Cd, supplemented with vitamin B12 and folic acid and in the combination of these two. After 28 days the liver function enzymes and oxidative stress parameters were measured. &lt;br/&gt;&lt;b&gt;Results:&lt;/b&gt; Cd is the silent killer of the hepatic system through the induction of oxidative stress in male rats. From this investigation, it is evident that the folic acid+vitamin B12 possess significant hepatoprotective and antioxidant activity against Cd-induced hepatotoxicity in the rat model. In addition, results revealed that the folic acid alone and or in combination with vitamin B12 blunted the hepatotoxic effect significantly. &lt;br/&gt;&lt;b&gt;Conclusions:&lt;/b&gt; Based on results obtained, it can be concluded that folic acid and vitamin B12 offer a protective effect in Cd-induced oxidative stress associated with hepatocellular injury. Folic acid and vitamin B12 can be considered as a potent natural antioxidant which has the capacity to provide protection against Cd-induced oxidative stress in the liver in rats. However, to elucidate the exact mechanism of this modulatory effect and to examine its potential therapeutic effects further studies are essential.

Neuroprotective effect of p-coumaric acid in rat model of embolic cerebral ischemia.

Stroke poses a crucial risk for mortality and morbidity. Our study aimed to investigate the effect of p-coumaric acid on focal cerebral ischemia in rats. Rats were randomly divided into four groups, namely Group I (control rats), Group II (ischemia rats), Group III (6 hr ischemia + p-coumaric acid rats) and Group IV (24 hr ischemia + p-coumaric acid rats). Cerebral ischemia was induced via intraluminal monofilament occlusion model. In all groups, the brain was removed after the procedure and rats were sacrificed. Malondialdehyde, superoxide dismutase and nuclear respiratory factor-1 were measured in the ischemic hemisphere. The histopathological changes were observed in the right hemisphere within the samples. Functional assessment was performed for neurological deficit scores. Following the treatment, biochemical factors changed significantly. Histopathologically, it was shown that p-coumaric acid decreased the oxidative damage. The neurological deficit scores of p-coumaric acid-treated rats were significantly improved after cerebral ischemia. Our results showed that p-coumaric acid is a neuroprotective agent on account of its strong anti-oxidant and anti-apoptotic features. Moreover, p-coumaric acid decreased the focal ischemia. Extra effort should be made to introduce p-coumaric acid as a promising therapeutic agent to be utilized for treatment of human cerebral ischemia in the future.

Xenotransplantation of human adipose derived mesenchymal stem cells in a rodent model of Huntington’s disease: motor and non-motor outcomes

Human mesenchymal stem cells (hMSCs) have been presented as alternative sources of cells to be transplanted into the brain in neurodegenerative disorders. In this regard, the efficacy of hMSCs transplants in reducing motor and non-motor deficits in a quinolinic acid (QA) rat model of Huntington’s disease (HD) was tested in the present study. After unilateral lesions in striatum by QA, the isolated and purified hMSCs from liposuction of healthy male donors were transplanted into the damaged striatum of the rats. The cells were stably transfected with a vector containing TurboGFP and JRed to make it possible to trace them after transplantation. Animals were tested by motor and non-motor function tests at different times after the cell transplantation. The hMSCs survived 7 weeks in the brains. An improvement was observed in behavioral tests such as apomophine-induced rotation, hanging wire, and rotarod for the hMSC-treated rats. Anxiety like behaviors were decreased in hMSCs-treated animals when they were examined using open field, elevated plus maze, light and dark box, and novelty suppressed feeding tests. Compared to QA, the hMSCs treatment decreased motor activities. These results confirmed the potential efficacy of hMSCs in treatment of behavioral defects in HD. Generally, the data demonstrated that xenologous transplantation of hMSCs could be considered as an ideal candidate for treatment of neurodegenerative diseases, especially HD.

Possible role of lysophosphatidic acid in rat model of hypoxic pulmonary vascular remodeling.

Pulmonary hypertension is characterized by cellular and structural changes in the vascular wall of pulmonary arteries. We hypothesized that lysophosphatidic acid (LPA), a bioactive lipid, is implicated in this vascular remodeling in a rat model of hypoxic pulmonary hypertension. Exposure of Wistar rats to 10% O2 for 3 weeks induced an increase in the mean serum levels of LPA, to 40.9 (log-detransformed standard deviations: 23.4-71.7) μM versus 21.6 (11.0-42.3) μM in a matched control animal group (P = 0.037). We also observed perivascular LPA immunohistochemical staining in lungs of hypoxic rats colocalized with the secreted lysophospholipase D autotaxin (ATX). Moreover, ATX colocalized with mast cell tryptase, suggesting implication of these cells in perivascular LPA production. Hypoxic rat lungs expressed more ATX transcripts (2.4-fold) and more transcripts of proteins implicated in cell migration: β2 integrin (1.74-fold), intracellular adhesion molecule 1 (ICAM-1; 1.84-fold), and αM integrin (2.70-fold). Serum from the hypoxic group of animals had significantly higher chemoattractant properties toward rat primary lung fibroblasts, and this increase in cell migration could be prevented by the LPA receptor 1 and 3 antagonists. LPA also increased adhesive properties of human pulmonary artery endothelial cells as well as those of human peripheral blood mononuclear cells, via the activation of LPA receptor 1 or 3 followed by the stimulation of gene expression of ICAM-1, β-1, E-selectin, and vascular cell adhesion molecule integrins. In conclusion, chronic hypoxia increases circulating and tissue levels of LPA, which might induce fibroblast migration and recruitment of mononuclear cells in pulmonary vasculature, both of which contribute to pulmonary vascular remodeling.

Neuroprotective effect of asiatic acid in rat model of focal embolic stroke.

Asiatic acid (AA) is a pleiotropic neuroprotective agent that has been shown to attenuate infarct volume in mouse and rat models of focal ischemia and has a long clinically relevant therapeutic time-window. Because in a future trial AA would be administered with tissue-plasminogen activator (t-PA), the only approved acute stroke therapy, we sought to determine the effect of AA when co-administered with t-PA in a rat focal embolic stroke model. Male rats were treated with AA (75 mg/kg) alone, low-dose t-PA (2.5 mg/kg) alone, or a combination of AA and low-dose t-PA at 3 h after inducing embolic stroke. AA significantly reduced infarct volume whereas low-dose t-PA alone did not reduce infarct volume compared with vehicle. Significantly, combination treatment further enhanced reduction of infarct volume versus AA alone. Treatment with AA reduced cytochrome c (CytoC) and apoptosis-inducing factor (AIF) release from brain mitochondria after ischemia. AA was also neuroprotective against L-glutamate-induced toxicity in primary cortical neurons. In summary, combination treatment with AA and low-dose t-PA at 3 h after embolic stroke reduces infarct volume, improves neurological outcome, and provides neuroprotection. The neuroprotective effects of AA were partially associated with reduction of AIF and CytoC release.

Protective roles of α-lipoic acid in rat model of mitochondrial DNA4834bp deletion in inner ear

The protective roles of alpha-lipoic acid in the rat model of mitochondrial DNA (mtDNA) 4834bp deletion in inner ear were investigated. Forty female Wistar rats at 4 weeks of age were divided into four groups: group A (D-galactose group, n=10), group B (D-galactose+alpha-lipoic acid group, n=10), group C (alpha-lipoic acid group, n=10), and group D (control group, n=10). Auditory brainstem response (ABR) was used to detect the hearing threshold. Colorimetry was used to analyze activity of superoxide dismutase (SOD) and concentration of malondialdehyde (MDA). The percentage of mtDNA4834bp deletion in inner ear was identified by real-time PCR. There was no significant difference in ABR threshold shift among all groups. The percentage of mtDNA4834bp deletion in group A was higher than that in other groups, but there was no significant difference in percentage of mtDNA4834bp deletion among groups B, C, and D. The activity of SOD in group A was lower than that in other groups. The concentration of MDA in group A was higher than that in other groups. It was concluded that there was no significant hearing loss when the percentage of mtDNA4834bp deletion was lower than 12.5%. Alpha-lipoic acid could prevent the reactive oxygen species (ROS)-induced mtDNA4834bp deletion in inner ear of rats.

Human neural stem cells genetically modified for brain repair in neurological disorders.

Existence of multipotent neural stem cells (NSC) has been known in developing or adult mammalian CNS, including humans. NSC have the capacity to grow indefinitely and have multipotent potential to differentiate into three major cell types of CNS, neurons, astrocytes and oligodendrocytes. Stable clonal lines of human NSC have recently been generated from the human fetal telencephalon using a retroviral vector encoding v-myc. One of the NSC lines, HB1.F3, carries normal human karyotype of 46XX and has the ability to self-renew, differentiate into cells of neuronal and glial lineages, and integrate into the damaged CNS loci upon transplantation into the brain of animal models of Parkinson disease, HD, stroke and mucopolysaccharidosis. F3 human NSC were genetically engineered to produce L-dihydroxyphenylalanine (L-DOPA) by double transfection with cDNA for tyrosine hydroxylase and guanosine triphosphate cylohydrolase-1, and transplantation of these cells in the brain of Parkinson disease model rats led to L-DOPA production and functional recovery. Proactively transplanted F3 human NSC in rat striatum, supported the survival of host striatal neurons against neuronal injury caused by 3-nitropro-pionic acid in rat model of HD. Intravenously introduced through the tail vein, F3 human NSC were found to migrate into ischemic lesion sites, differentiate into neurons and glial cells, and improve functional deficits in rat stroke models. These results indicate that human NSC should be an ideal vehicle for cell replacement and gene transfer therapy for patients with neurological diseases. In addition to immortalized human NSC, immortalized human bone marrow mesenchymal stem cell lines have been generated from human embryonic bone marrow issues with retroviral vectors encording v-myc or teromerase gene. These immortalized cell lines of human bone marrow mesenchymal stem cells differentiated into neurons/glial cells, bone, cartilage and adipose tissue when they were grown in selective inducing media. There is further need for investigation into the neurogenic potential of the human bone marrow stem cell lines and their utility in animal models of neurological diseases.

Urinary 8-Hydroxydeoxyguanosine Excretion as a Non-Invasive Marker of Neutrophil Activation in Animal Models of Inflammatory Bowel Disease

Background: Because free radicals contribute to ulcerative colitis and Crohn's disease, assessing oxidative load in vivo could provide a surrogate marker of inflammation and disease status. Methods: Electrochemical high-performance liquid chromatography was used to study urinary excretion of 8-hydroxydeoxyguanosine (8-OH-dGUA), formed by reaction of hydroxyl radicals with native DNA, in 2,4,6-trinitrobenzene-sulfonic acid (TNBS) and dextran sulfate (DSS) rat models of bowel inflammation. Bowel myeloperoxidase (MPO) and histopathology were also assessed. Results: TNBS enema (75 mg/kg in 50% ethanol) and oral DSS (6% via drinking water) both yielded an inflammatory response reflected by increases in bowel MPO that were significantly correlated with tissue injury. In both models urinary 8-OH-dGUA excretion was significantly correlated with bowel MPO activity and epithelial injury and remained at control levels when neutrophils (PMN) were eliminated, whereas epithelial injury and crypt erosion persisted despite neutropenia. Conclusions: Urinary 8-OH-dGUA excretion directly reflects PMN activation in vivo, thereby providing a non-invasive surrogate marker for inflammation in these models which is more indicative of PMN activation than either MPO activity, which does not distinguish inactive from active MPO, or epithelial status, which is independent of PMN activation in both models.