Rat Strains Research Articles

Effect of different melatonin-rich extract of Emprit ginger (Zingiber officinale var. amarum) doses on biochemical parameters in streptozotocin-induced diabetic rats

Background/Aim: Emprit ginger (Zingiber officinale var. amarum) is an Indonesian natural plant with various bioactivities, including antidiabetic properties. Several studies have shown that bioactivities can be attributed to the presence of flavonoids and also melatonin which playing a role in carbohydrate metabolism and blood sugar levels regulation. Ginger also has an effect on the lipid profile in studies in experimental animals. Therefore, this study aimed to determine the in vivo antidiabetic activity of melatonin-rich extract of Emprit ginger using blood sugar and lipid profiles parameters. Methods: The study procedure comprised 30 male white rats of Wistar strain, which were divided into 5 groups. These included: I - K-: negative control; II - K+: injected with streptozotocin (STZ) - nicotinamide (NA); III - P1: given STZ-NA + 100 mg/kg body weight (BW)/day ginger extract; IV - P2: given STZ-NA + 200 mg/kg BW/day ginger extract; and V - P3: injected with STZ-NA + metformin 300 mg/kg BW/day. In addition, the treatment was carried out for a total of 21 days, followed by the measurement of random blood sugar (RBS) levels and lipid profiles. Results: The highest pre-treatment RBS, triglyceride, cholesterol, HDL and LDL levels were 426.8 ± 55.8 mg/dL (P2), 142 ± 39.8 mg/dL (P2), 130.8 ± 21.7 mg/dL (K+), 53.4 ± 4.92 mg/dL (P1) and 61.67 ± 17.69 mg/ dL (K+), respectively. The results showed that the largest decrease in RBS was obtained in P3 by 262.8 ± 70.6 mg/dL, while P2 experienced the highest decrease in triglyceride levels by 83.66 ± 52.04 mg/dL. In addition, the largest decrease in cholesterol was in P3 by 50.2 ± 26.30 mg/dL, with P1 possessing the highest reduction in HDL by 15.4 ± 15.88 mg/dL. In terms of LDL, the largest decrease was obtained in P3, 20.44 ± 16.68 mg/dL. Based on the results, changes in biochemical parameters levels between all groups showed significant differences except for HDL. Conclusion: STZ-NA injection caused an increase in RBS and cholesterol in rats. Administration of melatonin-rich ginger extract led to a decrease in RBS, cholesterol and LDL and was more effective in the group given metformin. Melatonin-rich ginger extract at a dose of 200 mg/kg BW/day was more effective in reducing triglycerides compared to other clinical parameters.

Mechanism of streptozotocin to induce cardiac fibrosis through TNFa and BCL2 pathways in in silico and in vivo study

Background: Cardiac fibrosis is often associated with various heart-related problems such as heart failure, atrial arrhythmia, and sudden cardiac death, making it a leading cause of death globally. Diabetes-associated fibrosis, on the other hand, is influenced by activated cardiac fibroblasts and potentially involves fibrosis-inducing activity of macrophages, cardiomyocytes, and vascular cells. Streptozotocin (STZ) is a known diabetogenic agent, but inadequate preclinical data in animal models hinders its clinical success. Aim: This study aims to provide practical guidelines for STZ utilization in inducing Diabetes-associated cardiac fibrosis. Methods: The research was conducted in vivo using white rats (Rattus norvegicus) of the Wistar strain, induced with STZ at doses of 30mg/KgBW and 50mg/KgBW per injection. Observations were carried out at the 4th and 8th weeks, consisting of the measurement of blood sugar levels and the examination of heart muscle cell fibrosis. Subsequently, in silico validation of STZ's affinity with inflammatory receptors causing diabetes pathology, such as TNFα and BCL2, was performed. Results: The study results indicated that the administration of STZ led to an increase in random blood sugar levels and extensive fibrosis of heart muscle cells in mice. The optimal dose for the diabetes model experimented in this study was 50 mg/KgBW for 8 weeks. In silico tests revealed an affinity for TNFα (PDB ID 2AZ5) and BCL2 (PDB ID 6QGH). Conclusion: Consequently, it can be concluded that administering STZ to mice at a dose of 50 mg/KgBW for 8 weeks is an effective inducer of a diabetes-associated cardiac fibrosis model.

A Standardized Rat Model to Study Peri-implantitis of Transmucosal Osseointegrated Implants.

With the high incidence rate, distinctive implant characteristic and unique infection pattern, peri-implantitis (PI) requires a specially designed implant animal model for the researches on the pathogenesis and treatments. Previous small-animal PI models exhibit variability in implant site selection, design, and surgical procedures resulting in unnecessary tissue damage and less effectivity. Herein, a quantitative-analysis-based standardized rat model for transmucosal PI-related research was proposed. After dissecting the anatomic structures of the rat maxilla, we determined that placing the implant anterior to the molars in the rat maxilla streamlined the experimental period and enhanced animal welfare. We standardized the model by controlling the rat strain, gender, and size. The customized implant and a series of matched surgical instruments were appropriately designed. A clear, step-by-step surgical process was established. These designs ensured the success rate, stability, and replicability of the model. Each validation method confirmed the successful construction of the model. This study proposed a quantitative-analysis-based standardized transmucosal PI rat model with improved animal welfare and reliable procedures. This model could provide efficient invivo insights to study the pathogenesis and treatments of PI and preliminary screening data for further large-animal and clinical trials.

Transcriptomics and metabolomics analysis of the pathogenesis of a novel hyperlipidemia-susceptible rat strain.

To investigate the pathogenesis of hyperlipidemia in Wistar-SD Hypercholesterolemia (WSHc) rats and clarify the genetic and biological characteristics. Six 7-8-week-old WSHc rats were fed a high-fat diet (HFD), and another six were fed ordinary feed, with age-matched Wistar rats as the control group under the same treatment. After 16 weeks, serum lipid levels were measured. A transcriptomic analysis of the differences in gene expression of the liver related to cholesterol metabolism was conducted, and 119 differentially expressed genes were discovered through bioinformatics analysis and molecular biology verification. UHPLC-Q-TOF/MS was applied for lipidomic analysis of serum samples from each group. WSHc rats developed dyslipidemia after a high-fat diet was induced. Investigation of the gene profiles using the protein-protein interaction network and one-cluster clustering analysis identified SREBF1 as a HUB gene and NR1d1 as an independent key gene. SREBF1 and NR1d1 were further validated in molecular biology experiments, which was consistent with the transcriptomic results. Lipid metabolomics analysis identified seven lipid subclasses and 84 lipid molecules. The metabolic profiles of serum lipid media of the WSHc + HFD and WSHc + SC groups were significantly different compared to that of the control group by 62 and 70 lipid molecules, respectively. Differential metabolites were produced via sphingolipid and glycerophospholipid metabolism. A stable model of hypercholesterolemia in WSHc rats can be generated by feeding on a high-fat diet, and the pathogenesis mainly involves two key genes, SREBF1 and NR1d1, and the sphingolipid and glycerophospholipid metabolism pathways.

Comparative proteomic analysis of renal tissue of normotensive and hypertensive rats.

Comparative proteomic analysis of kidney tissue from normotensive (WKY) and spontaneously hypertensive (SHR) rats revealed quantitative and qualitative changes in renal proteins. The number of renal proteins specific for WKY rats (blood pressure 110-120 mm Hg) was 13-16. There were 20-24 renal proteins specific for SHR (blood pressure 180 mm Hg and more). The total number of identified renal proteins common for both rat strains included 972-975 proteins. A pairwise comparison of all possible (SHR-WKY) variants identified 8 proteins specific only for normotensive (WKY) animals, and 7 proteins specific only for hypertensive ones (SHR). Taking into consideration their biological roles, the lack of some enzyme proteins in hypertensive rats (for example, biliverdin reductase A) reduces the production of molecules exhibiting antihypertensive properties, while the appearance of others (e.g. betaine-homocysteine S-methyltransferase 2, septin 2, etc.) can be interpreted as a compensatory reaction. Renal proteins with altered relative content (with more than 2.5-fold change) accounted for no more than 5% of all identified proteins. Among the proteins with an increased relative content in hypertensive animals, the largest group consisted of proteins involved in the processes of energy generation and carbohydrate metabolism, as well as antioxidant and protective proteins. In the context of the development of hypertension, the identified relative changes can apparently be considered compensatory. Among the proteins with the most pronounced decrease in the relative content in hypertensive rats, the dramatic reduction in acyl-CoA medium-chain synthetase-3 (ACSM3) appears to make an important contribution to the development of renal pathology in these animals.

Tactile stimulation of young WAG/Rij rats prevents development of depression but not absence epilepsy.

Investigations in Wistar Albino Glaxo from Rijswijk (WAG/Rij) rats that are susceptible to genetic absence epilepsy have demonstrated that environmental modifications affect absence seizures. Previously, we showed that neonatal tactile stimulations produce disease-modifying effect on genetically determined absence epilepsy and associated depression in Wag/Rij rats. The study presented here examined the effect of TS during late ontogenesis (adolescence and young adulthood) on epilepsy and depression outcomes in this genetically epileptic rat strain. On postnatal day (PND) 38, male WAG/Rij rats randomly were assigned to either the tactile stimulation (TS), handled or control group (unhandled) with 8 animals in each group. Following a 7-day adaptation period to their new surroundings, the animals were submitted to tactile stimulation from PND 45 to PND 90, five days per week, for 5 min daily. The tactile-stimulated rat was removed from its cage, placed on the experimenter's lap, and had its neck and back gently stroked by the researcher. The handled rats were taken to another cage and left alone for 5 min daily from PND 45 to PND 90. The control rats were left undisturbed in their home cage, except for regular cage cleaning. After PND 90, all rats were left undisturbed until behavioral testing and EEG recording. When the animals were 7 months old, they were subjected to the sucrose consumption test (SCT) and the forced swimming test (FST). Electroencephalogram (EEG) recordings were made at 8 months of age in order to measure electroencephalographic seizure activity, thus, the spike-wave discharges (SWDs). Tactile-stimulated rats showed increased sucrose consumption and number of approaches to the sucrose solution in the SCT when compared with the handled and control rats. In the FST, rats in TS group showed lower immobility time and greater immobility latency, active swimming time and diving frequency than the handled and control rats. The duration and the number of seizures were not different amongst the groups. The data obtained suggest that TS in young rats is able to prevent depression in WAG/Rij rats.

Effect of Pirdot Leaf Extract (Saurauia Vulcani Korth ) on SGPT and SGOT Value in Wistar Strain Rats Induced by Salmonella Typhimurium.

Typhoid fever is an acute disease caused by Salmonella typhimurium that can invade the liver and cause symptoms of hepatomegaly,jaundice.Biochemically, these symptoms can be assessed by seeing the SGPT and SGOT levels increase. Pirdot Leaf is an herbal plant found in the Toba area of North Sumatra which has a lot of bioactive potential,namely flavonoids,steroids, saponins. Flavonoids are active substances that can overcome the inflammatory process, it is expected that the administration of Pirdot leaf extract can reduce levels of SGOT and SGPT in mice induced Salmonella Typhimurium. The purpose of this study was to determine the effect of ethanol extract of pirdot leaves on SGPT and SGOT values in rat models induced by Salmonella typhimurium. Methods: This study used 32 samples divided into four groups namely: Normal group, Negative group, Positive group and Treatment group. Results: The results were obtained for normal control SGPT (27,85) negative control (37,80) positive control (27,30) and for Dick treatment (26,21). The results of the study for SGPT obtained normal control (73,18), negative control (120,23), positive control (92,89), and treatment control (78,68). Giving ethanol extract of pirdot leaves effect on reducing SGPT and SGOT levels in wistar strain mice induced Salmonella typhimurium.

The Comparative Study of Physical Exercise Towards Brain Natriuretic Peptide (BNP) and Malondialdehyde (MDA) as Oxidative Stress Markers in Rattus Novergicus Wistar Strain Rats

Background: Physical exercise has an effect on biological functions, namely a positive effect in terms of cell repair and a negative effect, namely inhibiting or damaging cells. Strenuous physical exercise can increase muscle injury and oxidative stress in individuals who are not conditioned or are not used to physical exercise. In addition, oxidative stress also plays a role in chronic fatigue syndrome. This occurs because the speed of energy demand exceeds the speed and ability of the oxygen transport system to supply oxygen to the mitochondria. The heart muscle is a muscle that has a major role in physical exercise. Oxidative stress plays an important role in the pathogenesis of myocardial infarction. Objectives: The purpose of this research is to determine the difference between aerobic and anaerobic exercise in the formation of free radicals. The formation of free radicals can be predicted by measuring levels of malondialdehyde (MDA) and Brain Natriuetic Peptide (BNP). Methods: The design used in this study was an experimental study in vivo with a pretest-posttest design with a comparison group. The subjects of this study were 28 male Wistar rats, Rattus novergicus, which were divided into 6 treatment groups and 1 comparison group. The data is taken by doing treadmill physical exercise with a speed of 20m / minute for aerobics and 35m / minute for anaerobics. Different tests of average MDA and BNP levels were used using independent t-tests, ANOVA, and post hoc. Result: The results showed a decrease in MDA and BNP levels in the aerobic treatment group and an increase in anaerobic compared to the comparison group. The analysis showed that there was a significant difference between the aerobic group for 1 day, 3 times a week, and 7 days, respectively, with p 0.05. Conclusion: It can be concluded that aerobic and anaerobic physical exercise performed 1 day, 3 times a week, and 7 consecutive days can increase the antioxidant defence system so that oxidative stress decreases, which is indicated by a decrease in MDA and BNP levels.

Effects of high dose of long-term ethanol exposure on oxidative damage of spleen in experimental rat model

Background: Alcoholic beverages have been used in human societies at least since the beginning of recorded history. Research has demonstrated sufficiently to our understanding of the relation of drinking to specific disorders, and has shown that the relation between alcohol consumption and health outcomes is complex and multidimensional. Methods: In this study we had demonstrated the role of oxidative stress in long-term ethanol induced spleen damage in 16-18 week-old male albino rats of Wistar strain weighing 200- 220 g. Results: Ethanol exposure (1.6 g ethanol/ kg body wt/ day for 12 weeks) caused significant decrease in reduced glutathione (GSH) concentration and activities of superoxide dismutase and glutathione reductase; while significant increase in thiobarbituric acid reactive substances (TBARS) content and glutathione s-transferase activity in spleen homogenate. Conclusion: Our study revealed that higher doses of ethanol (1.6 g/ kg body weight/ day) for a long period caused significant oxidative stress in the spleen. Intermediates of oxygen reduction may be associated with the development of ethanol induced organ damage.

Anti-inflammatory activity of An Ethanol Extract of Pucuk Merah (Syzigium myrtifolium Walp.) in vivo

Compared with classical Utilization of medicinal plants with anti-inflammatory properties, it needs to be done to find alternative treatments with relatively more minor side effects, such as Syzygium myrtifolium walp. This study aims to determine the effective dose of ethanol extract of pucuk merah as an anti-inflammatory in 30 male white rats of the Wistar strain. Testing the extract's anti-inflammatory effect was measured by measuring the edema volume on the soles of the rats' feet after being induced with 1% carrageenan with a pletismometer. The test animals were divided into six treatment groups, namely group 1 negative control (Na CMC 1%), group 2 positive control (Na Diclofenac 50 mg/KgBW), group 3 (dose of pucuk merah leaves extract 75 mg/KgBW), group 4 (quantity of pucuk merah leaves extract 100 mg/kgBW), and group 5 (amount of pucuk merah leaves extract 125 mg/kg BW), with observation times of 30, 60, 90, 120, 150, and 180 minutes. The results showed that rats in group 5 with a dose of pucuk merah (125 mg/kgBW) had the best anti-inflammatory effect, with an anti-inflammatory potential of 97% compared to diclofenac sodium.

Whey preparation as an adjuvant to minimise the Intestinal inflammatory status in mucositis rat model

To study the effect of Whey Preparation on intestinal mucositis, model developed by administration of single dose of etoposide (60mg/Kg body wt., i.p). The experimental procedure included Adult albino rats (10±1 week old) of Wistar strain (n=30, 6/group). Freshly prepared whey preparation-(100 and 200mg/Kg/body wt.) was administered by orogastric gavage- Pre, both pre and post etoposide injection. Effectiveness of whey preparation was determined by estimating the biochemical parameters including intestinal Tumor Necrosis Factor-α, Interleukin-6, sodium potassium ATPase, inflammatory markers- Cyclooxygenase and Myeloperoxidase along with Nitric Oxide and reduced Glutathione with and without intervention after 72 hrs. of etoposide injection. There was a significant increase in the Tumor Necrosis Factor –α, Interleukin-6 levels and extent of apoptosis in etoposide controls. Etoposide administration caused a significant decreased the activity of Na+-K+ ATPase and reduced glutathione levels in intestinal tissue. However, in the post treatment groups, Tumor Necrosis Factor–α, Interleukin-6 as well as extent of apoptosis were reverted to normal after whey preparation administration.Whey Preparation gavage in both the study groups- pre and both pre and post etoposide exposure showed that intervention was able to preserve/ prevent changes in the biochemical activity. The results support the WP potentials to reduce the deleterious effects of etoposide on normal cells, which leads to mucositis.

Differential Effects of Neonatal Ventral Hippocampus Lesion on Behavior and Corticolimbic Plasticity in Wistar-Kyoto and Spontaneously Hypertensive Rats.

Dysfunction of the corticolimbic system, particularly at the dendritic spine level, is a recognized core mechanism in neurodevelopmental disorders such as schizophrenia. Neonatal ventral hippocampus lesion (NVHL) in Sprague-Dawley rats induces both a schizophrenia-related behavioral phenotype and dendritic spine pathology (reduced total number and mature spines) in corticolimbic areas, which is mitigated by antipsychotics. However, there is limited information on the impact of rat strain on NVHL outcomes and antipsychotic effects. We compared the behavioral performance in the open field, novel object recognition (NORT), and social interaction tests, as well as structural neuroplasticity with the Golgi-Cox stain in Wistar-Kyoto (WKY) and spontaneously hypertensive (SH) male rats with and without NVHL. Additionally, we explored the effect of the atypical antipsychotic risperidone (RISP). WKY rats with NVHL displayed motor hyperactivity without impairments in memory and social behavior, accompanied by dendritic spine pathology in the neurons of the prefrontal cortex (PFC) layer 3 and basolateral amygdala. RISP treatment reduced motor activity and had subtle and selective effects on the neuroplasticity alterations. In SH rats, NVHL increased the time spent in the border area during the open field test, impaired the short-term performance in NORT, and reduced social interaction time, deficits that were corrected after RISP administration. The NVHL caused dendritic spine pathology in the PFC layers 3 and 5 of SH rats, which RISP treatment ameliorated. Our results support the utility of the NVHL model for exploring neuroplasticity mechanisms in schizophrenia and understanding pharmacotherapy.

Differential expression of alpha-synuclein in the hippocampus of SHR and SLA16 isogenic rat strains

Two inbred strains, Lewis (LEW) and Spontaneously Hypertensive Rats (SHR), are well-known for their contrasting behavior related to anxiety/emotionality. Studies with these two strains led to the discovery of the Quantitative Trait Loci (QTL) on chromosome 4 (Anxrr16). To better understand the influences of this genomic region, the congenic rat strain SLA16 (SHR.LEW-Anxrr16) was developed. SLA16 rats present higher hyperactivity/impulsivity, deficits in learning and memory, and lower basal blood pressure than the SHR strain, even though genetic differences between them are only in chromosome 4. Thus, the present study proposed the alpha-synuclein and the dopaminergic system as candidates to explain the differential behavior of SHR and SLA16 strains. To accomplish this, beyond the behavioral analysis, we performed (I) the Snca gene expression and (II) quantification of the alpha-synuclein protein in the hippocampus (HPC), prefrontal cortex (PFC), and striatum (STR) of SHR and SLA16 strains; (III) sequencing of the 3′UTR of the Snca gene; and (IV) evaluation of miRNA binding in the 3′UTR site. A Single Nucleotide Polymorphism (SNP) was identified in the 3′UTR of the Snca gene, which exhibited upregulation in the HPC of SHR compared to SLA16 females. Alpha-synuclein protein was higher in the HPC of SHR males compared to SLA16 males. The results of this work suggested that differences in alpha-synuclein HPC content could be influenced by miRNA regulation and associated with behavioral differences between SHR and SLA16 animals.

Comparative Study of Immunodeficient Rat Strains in Engraftment of Human-Induced Pluripotent Stem Cell-Derived Airway Epithelia.

The airway epithelia (AE) play a role in the clearance of foreign substances through ciliary motility and mucus secreted. We developed an artificial trachea that is made of collagen sponges and polypropylene mesh for the regeneration of the tracheal defect, and it was used for a clinical study. Then, a model in which the luminal surface of an artificial trachea was covered with a human-induced pluripotent stem cell-derived AE (hiPSC-AE) was transplanted into the tracheal defect of nude rats to promote epithelialization. In the future, this model was expected to be applied to research on infectious diseases and drug discovery as a trachea-humanized rat model. However, at present, sufficient engraftment has not been achieved to evaluate functional recovery in transplanted cells. Therefore, this study focused on immunosuppression in recipient rats. Nude rats lack T cell function and are widely used for transplantation experiments; however, more severe immunosuppressed recipients are preferred for xenotransplantation. Several strains of immunodeficient rats were created as rats that exhibit more severe immunodeficiency until now. In this study, to establish a trachea-humanized rat model in which human AE function can be analyzed to improve engraftment efficiency, engraftment efficiency in nude rats and X-linked severe combined immunodeficiency (X-SCID) rats following hiPSC-AE transplantation was compared. In the analysis of the proportion of engrafted cells in total cells at the graft site, the engraftment efficiency of epithelial cells tended to be high in X-SCID rats, although no statistical difference was found between the two groups, whereas the engraftment efficiency of mesenchymal cells was higher in X-SCID rats. Furthermore, the number of immune cells that accumulated in the grafts showed that a pan T cell marker, that is, CD3-positive cells, did not differ between the two strains; however, CD45-positive cells and major histocompatibility complex (MHC) class II-positive cells significantly decreased in X-SCID rats. These results indicate that X-SCID rats are more useful for the transplantation of hiPSC-AE into the tracheae to generate trachea-humanized rat models.

Evaluation of Acute Toxicity and Phytochemical Analysis of Gliricidia sepium and Xylopia aethiopica Extracts

Objectives: Gliricidia sepium and Xylopia aethiopica are frequently utilized in traditional medicine in Ivory Coast. To mitigate potential risks associated with their uninformed use, it is crucial to assess their safety levels. This study was aimed at evaluating the acute toxicity and analyzing the phytochemicals in ethanolic extracts of Gliricidia sepium leaf and Xylopia aethiopica fruit.
 Materials and Methods: Triphytochemistry was carried out using staining and precipitation methods. While the Metabolite determinations were conducted via spectrophotometry. The assessment of acute toxicity followed the OECD protocol 423, employing female rats of the Wistar strain.
 Results: Phytochemical analysis revealed that Ethanolic extracts of Xylopia aethiopica fruit (XAF) contains 7.72% polyphenols, 4.09% alkaloids, 0.34% tannins, 0.12% saponins, and 0.001% terpenoids. In comparison, Gliricidia sepium leaf (GSL) exhibited levels of 7.49% polyphenols, 3.41% alkaloids, 0.47% tannins, 0.01% saponins, and 0.51% terpenoids. The acute toxicity study demonstrated the absence of mortality and major toxicity issues at maximum doses of 5000 mg/kg body weight.
 Conclusion: Ethanolic extracts of XAF and GSL, do not exhibit any acute toxic effect and they both contain some phytochemicals. This validates the frequent utilization and provides assurance to communities usings these plants.

Bleeding time and clotting time post-extraction Rattus norvegicus tooth treated with ethanol extract gel from Terminalia cattapa L. leaves

Link of Video Abstract: https://youtu.be/iJSDiYl-BmA Introduction: Post-extraction bleeding is a complication that is often encountered in dental practice. A decrease in the number of platelets will increase the risk of bleeding. If left untreated, complications can range from hematoma to severe blood loss. The use of medicinal plants is common in traditional medicine throughout the world. Flavonoids and tannins are the main compounds that play a role in the blood clotting process. The ethanol extract of Terminalia catappa L. leaves contains: saponins, alkaloids, tannins, flavonoids, triterpenoids, and phenols. This research aims to determine bleeding time and clotting time after tooth extraction. White mice were given ethanol extract gel from Terminalia cattapa L. leaves. Method: Study design using randomized with post-test only control group design, in vivo. A population of 35 male white rats (Rattus norvegicus) of the Wistar strain, were grouped randomly into 7 groups. The extraction of white rat teeth using artery clamps, measurement of bleeding time and clotting time using three stopwatches, and the results were averaged. Result: The results of the research showed that the ethanol extract gel of Terminalia cattapa L. leaves had a shorter bleeding time and clotting time than pure gel, after tooth extraction from white rats. Conclusion: Terminalia catappa L. leaf ethanol extract gels have the ability to shorten bleeding time and clotting time and the best gel concentration is 50%.

The Effect of Topical Gel Secretome Hypoxic Mesenchymal Stem Cells (SH-MSCs) on IL-6 and TGF- β Gene Expression (Experimental Study in Male Wistar Alopecia-Like Rat Models Induced by Fluconazole)

Alopecia induced by the accumulation of reactive oxygen species (ROS) stimulates changes in the immune and neuroendocrine systems. Hair follicles have dermal papillary cells (DPCs) that bind to corticotropin-releasing factor (CRF) receptors. Research shows that transforming growth factor (TGF-β) is one of the expressions that can be an indication of the influence of CRF. The effect of CRF itself is to cause hair loss. The purpose of this study was to determine the Secretome of Hypoxia Mesenchymal Stem Cells (SH-MSCs) against IL-6 expression and TGF-β expression. This study used experimentally in vivo with the Post Test Only Control Group Design method. The subjects of this study were male rats of Wistar strain which were divided into 4 treatments consisting of 1 healthy group, 1 negative control group, 1 treatment group with SH-MSCs dose 10% in a dose of 200 mg/rat/day gel, and 1 more treatment group with SH-MSCs dose 20% in a dose of 200 mg/rat/day. On the 21st day, IL-6 expression and TGF-β expression were examined. Data were analyzed using the One-Way ANOVA Test and the Kruskall-Wallis Test to determine the effect of each group. The One-Way ANOVA test showed the results of IL-6 expression (p = 0.000) showed a significant difference (p < 0.05) and the Kruskall-Wallis test of TGF-β expression (p = 0.000) with SH-MSCs dose 200 was a significant difference (p < 0.05). The administration of 10% and 20% doses of SH-MSCs in 200 mg gel may decrease IL-6 expression. Dosed SH-MSCs 20%increased TGF-β expression in alopecia-like rats. The development of the use of SH-MSCs is expected to be an alternative to alopecia therapy that is more beneficial and safe for the body.

Post-stress expression of genes involved in neuroplasticity in the hippocampus and blood of rats with different level of nervous system excitability

The causes and mechanisms of most mental disorders remain unclear. While stress is known to trigger depressive and anxiety disorders, the role of genetically determined individual differences in forming vulnerability to post-stress neurochemical disorders, including those that affect neuroplasticity, remains unresolved. Early studies suggest that acute and chronic stress lead to elevated glucocorticoid levels in the bloodstream and alter the expression of glucocorticoid and mineralocorticoid receptors. Additionally, both forms of stress can decrease the levels of brain-derived neurotrophic factor (BDNF), which plays a role in neuronal growth, development, and synapse building [1]. However, current studies insufficiently explain the complete mechanism of the stress response as they only explore variations in post-stress alteration of gene expression for proteins related to differing nervous system functional characteristics. The strains of rats from the Biocollection of the Pavlov Institute of Physiology, RAS, are a convenient model for studying the impact of genetically determined nervous system features on stress reactivity. The strains, selected based on the threshold of nervous system excitability [2], include HT (high threshold of excitability, low excitability) and LT (low threshold of excitability, high excitability) strains. These strains display contrasting responses to extended emotional and painful stress and exhibit unique changes in brain structures implicated in emotional regulation and stress reactivity at the molecular, cellular, and epigenetic levels [2]. The aim of this study is to examine the mRNA levels of genes encoding glucocorticoid and mineralocorticoid receptors (NR3C1, NR3C2) and brain-derived neurotrophic factor (BDNF) in the hippocampus and blood of rat strains that exhibit contrasting nervous system excitability. The study investigates interstrain variations in animals under non-stressful conditions and changes in response to prolonged exposure to emotional and painful stimuli. The experiment utilized 96 animals, with 6 animals in both the control and experimental groups at each time point. The stress model utilized was long-term emotional and painful stress as per K. Gecht [2]. The study assessed the expression of genes for glucocorticoid receptors and neurotrophic factor by isolating RNA from the hippocampus and blood of rats of two strains decapitated at 1, 7, 24, and 60 days post-stress. Gene expression analysis was conducted through real-time PCR and underwent further data processing using the ΔΔCt method. The statistical tests employed included the Kruskal–Wallis and Mann–Whitney tests. The analysis of the expression of the observed genes in intact animals demonstrates that highly excitable LT rats have a significantly lower level of expression of the nr3c2 gene, which encodes the mineralocorticoid receptor in the hippocampus, when compared to the low excitable HT strain. When studying the short-term and long-term effects of stress on the expression of the observed genes (nr3c1, nr3c2, bdnf), a decline was observed in the level of bdnf mRNA in the hippocampus of the LT strain 60 days after stress. The study suggests that the genetically determined characteristics of highly excitable animals affect the weakened adaptive abilities of their nervous system. One of the markers of this weakening is the reduced level of mRNA for the nr3c2 gene in the hippocampus under normal conditions, as well as a decrease in the expression of the bdnf gene in response to stress.

Changes in the glutamate/gaba system in the hippocampus of rats with age and during the Alzheimer’s disease signs development

GABA and glutamate are the most abundant neurotransmitters in the CNS and play a pivotal part in synaptic stability/plasticity. Glutamate and GABA homeostasis is important for healthy aging and reducing the risk of various neurological diseases, while long-term imbalance can contribute to the development of neurodegenerative disorders, including Alzheimer’s disease (AD). Its normalization discussed as a promising strategy for the prevention and/or treatment of AD, however, data on changes in the GABAergic and glutamatergic systems in with age, as well as in the dynamics of AD development, are limited. It is not clear whether the imbalance of the excitatory/inhibitory systems is a cause or a consequence of the development of the disease. Here we analyzed age-related alterations of the expression of glutamate, GABA, and enzymes that synthesize them (glutaminase, glutamine synthetase, GABA-T, and GAD67), transporters (GLAST, GLT-1, and GAT1), and relevant receptors (GluA1, NMDAR1, NMDA2B, and GABAAr1) in the whole hippocampus of Wistar rats and of senescence-accelerated OXYS rats, a model of the most common (> 95%) sporadic AD. Our results suggest that there is a decline of glutamate and GABA signaling with aging in the hippocampus of the both rat strains. However, we have not identified significant changes or compensatory enhancements in this system in the hippocampus of OXYS rats during development of neurodegenerative processes that are characteristic of AD.

Is alteration of ERK1/2 and p38MAPK signaling pathways activity a general mechanism of Alzheimer’s disease and age-related macular degeneration development?

Age is the primary risk factor for Alzheimer’s disease (AD), the most prevalent progressive senile dementia, and age-related macular degeneration (AMD), the main cause of vision loss in individuals over 60. Effective prevention and treatment of these neurodegenerative conditions are lacking due to incomplete knowledge of their pathogenesis. Risk factors such as smoking, hypertension, hypercholesterolemia, atherosclerosis, obesity, and malnutrition intersect with the pathogenesis mechanisms of both AD and AMD. Oxidative stress, inflammation, mitochondrial dysfunction, and impaired proteostasis maintenance are among the pathological factors associated with the aggregation and accumulation of abnormal extracellular deposits — senile plaques in the brains of AD patients and drusen in AMD patients. Alterations in the regulation of MAPK signaling pathways with age may be associated to the emergence of these abnormalities. Impaired MAPK signaling was confirmed as a significant contributor to the pathogenesis of AD through the results of numerous investigations. MAPK is a potential target for therapeutic interventions. Information on its age-related changes, however, is limited. Virtually no data exist on retinal MAPK activity during AD and AMD development. This study aims to compare changes in ERK1/2 and p38MAPK signaling activity in brain and retina structures with age and AD/AMD progression. Wistar and OXYS rats were used as models of accelerated aging that show concomitant signs of AD and AMD. At the initial stage of the study, we examined the gene expression related to ERK1/2 and p38MAPK signaling pathways via comparing the transcriptomes (RNA-seq data) of the retina, prefrontal cortex, and hippocampus of OXYS and Wistar rats. The analysis was conducted when the rats were 20 days old and showed no signs of AMD and AD symptoms, during their manifestation period (age 3–5 months) and active progression stage (age 18 months). Changes in gene expression, involved in EPK1/2 [1] and p38MAPK signaling pathways according to the Rat Genome Database, are tissue-specific and dependent on the animal genotype. In the retina, the number of genes associated with ERK1/2 and p38MAPK decreased in both Wistar and OXYS rats with age and was minimal at 18 months of age. The greatest differences in the expression levels of these genes were detected when the rats were 20 days old, at the preclinical stage of AMD-like pathology development in OXYS rats. Both activators and inhibitors of the EPK1/2 and p38MAPK pathways were present among the differentially expressed genes (DEGs) with increased mRNA levels. At 3 months, the number of DEGs decreased, while activator genes predominated among those with increased mRNA levels. At 18 months, the retina of OXYS rats displayed only signs of decreased activity in signaling pathways at the gene expression level. Age-related changes in gene expression profiles related to the ERK1/2 [2] and p38MAPK [3, 4] signaling pathways in Wistar rats differed between brain structures and the retina. In the prefrontal cortex and hippocampus, the number of genes increased with age, and the expression differed between OXYS and Wistar rats. However, no signs of significant activation of the signaling pathway were observed. The phosphorylation level of ERK1/2 and p38MAPK signaling pathway kinases serves as an objective indicator of their activity. For protein level evaluation via Western blot analysis, we examined these levels in the retina, prefrontal cortex, and hippocampus. In both rat strains, a significant increase in phosphorylated forms of ERK1/2 and p38MAPK was observed with aging in all examined tissues. Simultaneously, accumulation of the substance became more active in OXYS rats and increased with progression of AD and AMD symptoms. Therefore, the results indicate that no significant changes in the activity of ERK1/2 and p38MAPK signaling cascades in the retina and brain structures are observed during normal aging of Wistar rats and accelerated aging of OXYS, both at the gene expression and protein level. AD and AMD pathological signs in OXYS rats were found to be associated with increased phosphorylation of ERK1/2 and p38MAPK, suggesting that enhancement of MAPK pathways may be a common mechanism for the early development of AD and AMD.