MyMedR

Displaying publications 61 - 80 of 370 in total

Abstract:

Sort:

Fulltext 1H NMR-based metabolomics investigation of copper-laden rat: a model of Wilson's disease

Xu J, Jiang H, Li J, Cheng KK, Dong J, Chen Z

PLoS One, 2015;10(4):e0119654.
PMID: 25849323 DOI: 10.1371/journal.pone.0119654

Wilson's disease (WD), also known as hepatoleticular degeneration (HLD), is a rare autosomal recessive genetic disorder of copper metabolism, which causes copper to accumulate in body tissues. In this study, rats fed with copper-laden diet are used to render the clinical manifestations of WD, and their copper toxicity-induced organ lesions are studied. To investigate metabolic behaviors of 'decoppering' process, penicillamine (PA) was used for treating copper-laden rats as this chelating agent could eliminate excess copper through the urine. To date, there has been limited metabolomics study on WD, while metabolic impacts of copper accumulation and PA administration have yet to be established.

Matched MeSH terms: Rats, Wistar
Fulltext A Pharmacological Examination of the Cardiovascular Effects of Malayan Krait (Bungarus candidus) Venoms

Chaisakul J, Rusmili MR, Hodgson WC, Hatthachote P, Suwan K, Inchan A, et al.

Toxins (Basel), 2017 03 29;9(4).
PMID: 28353659 DOI: 10.3390/toxins9040122

Cardiovascular effects (e.g., tachycardia, hypo- and/or hypertension) are often clinical outcomes of snake envenoming. Malayan krait (Bungarus candidus) envenoming has been reported to cause cardiovascular effects that may be related to abnormalities in parasympathetic activity. However, the exact mechanism for this effect has yet to be determined. In the present study, we investigated thein vivoandin vitrocardiovascular effects ofB. candidusvenoms from Southern (BC-S) and Northeastern (BC-NE) Thailand. SDS-PAGE analysis of venoms showed some differences in the protein profile of the venoms.B. candidusvenoms (50 µg/kg-100 µg/kg, i.v.) caused dose-dependent hypotension in anaesthetised rats. The highest dose caused sudden hypotension (phase I) followed by a return of mean arterial pressure to baseline levels and a decrease in heart rate with transient hypertension (phase II) prior to a small decrease in blood pressure (phase III). Prior administration of monovalent antivenom significantly attenuated the hypotension induced by venoms (100 µg/kg, i.v.). The sudden hypotensive effect of BC-NE venom was abolished by prior administration of hexamethonium (10 mg/kg, i.v.) or atropine (5 mg/kg, i.v.). BC-S and BC-NE venoms (0.1 µg/kg-100 µg/ml) induced concentration-dependent relaxation (EC50= 8 ± 1 and 13 ± 3 µg/mL, respectively) in endothelium-intact aorta. The concentration-response curves were markedly shifted to the right by pre-incubation with L-NAME (0.2 mM), or removal of the endothelium, suggesting that endothelium-derived nitric oxide (NO) is likely to be responsible for venom-induced aortic relaxation. Our data indicate that the cardiovascular effects caused byB. candidusvenoms may be due to a combination of vascular mediators (i.e., NO) and autonomic adaptation via nicotinic and muscarinic acetylcholine receptors.

Matched MeSH terms: Rats, Wistar
Antipsychotic Potential and Safety Profile of TPGS-Based Mucoadhesive Aripiprazole Nanoemulsion: Development and Optimization for Nose-To-Brain Delivery

Kumbhar SA, Kokare CR, Shrivastava B, Gorain B, Choudhury H

J Pharm Sci, 2021 04;110(4):1761-1778.
PMID: 33515583 DOI: 10.1016/j.xphs.2021.01.021

Delivering therapeutics to the brain using conventional dosage forms is always a challenge, thus the present study was aimed to formulate mucoadhesive nanoemulsion (MNE) of aripiprazole (ARP) for intranasal delivery to transport the drug directly to the brain. Therefore, a TPGS based ARP-MNE was formulated and optimized using the Box-Behnken statistical design. The improved in vitro release profile of the formulation was in agreement to enhanced ex vivo permeation through sheep mucous membranes with a maximum rate of permeation co-efficient (62.87 cm h-1 × 103) and flux (31.43 μg cm-2.h-1). The pharmacokinetic profile following single-dose administration showed the maximum concentration of drug in the brain (Cmax) of 15.19 ± 2.51 μg mL-1 and Tmax of 1 h in animals with ARP-MNE as compared to 10.57 ± 1.88 μg mL-1 and 1 h, and 2.52 ± 0.38 μg mL-1 and 3 h upon intranasal and intravenous administration of ARP-NE, respectively. Further, higher values of % drug targeting efficiency (96.9%) and % drug targeting potential (89.73%) of ARP-MNE through intranasal administration were investigated. The studies in Wistar rats showed no existence of extrapyramidal symptoms through the catalepsy test and forelimb retraction results. No ex vivo ciliotoxicity on nasal mucosa reflects the safety of the components and delivery tool. Further, findings on locomotor activity and hind-limb retraction test in ARP-MNE treated animals established its antipsychotic efficacy. Thus, it can be inferred that the developed ARP-MNE could effectively be explored as brain delivery cargo in the effective treatment of schizophrenia without producing any toxic manifestation.

Matched MeSH terms: Rats, Wistar
Preparation, characterization, and optimization of asenapine maleate mucoadhesive nanoemulsion using Box-Behnken design: In vitro and in vivo studies for brain targeting

Kumbhar SA, Kokare CR, Shrivastava B, Gorain B, Choudhury H

Int J Pharm, 2020 Aug 30;586:119499.
PMID: 32505580 DOI: 10.1016/j.ijpharm.2020.119499

The tight junctions between capillary endothelial cells of the blood-brain barrier (BBB) restricts the entry of therapeutics into the brain. Potential of the intranasal delivery tool has been explored in administering the therapeutics directly to the brain, thus bypassing BBB. The objective of this study was to develop and optimize an intranasal mucoadhesive nanoemulsion (MNE) of asenapine maleate (ASP) in order to enhance the nasomucosal adhesion and direct brain targetability for improved efficacy and safety. Box-Behnken statistical design was used to recognize the crucial formulation variables influencing droplet size, size distribution and surface charge of ASP-NE. ASP-MNE was obtained by incorporating GRAS mucoadhesive polymer, Carbopol 971 in the optimized NE. Optimized ASP-MNE displayed spherical morphology with a droplet size of 21.2 ± 0.15 nm and 0.355 polydispersity index. Improved ex-vivo permeation was observed in ASP-NE and ASP-MNE, compared to the ASP-solution. Finally, the optimized formulation was found to be safe in ex-vivo ciliotoxicity study on sheep nasal mucosa. The single-dose pharmacokinetic study in male Wistar rats revealed a significant increase in concentration of ASP in the brain upon intranasal administration of ASP-MNE, with a maximum of 284.33 ± 5.5 ng/mL. The time required to reach maximum brain concentration (1 h) was reduced compared to intravenous administration of ASP-NE (3 h). Furthermore, it has been established during the course of present study, that the brain targeting capability of ASP via intranasal administration had enhanced drug-targeting efficiency and drug-targeting potential. In the animal behavioral studies, no extrapyramidal symptoms were observed after intranasal administration of ASP-MNE, while good locomotor activity and hind-limb retraction test established its antipsychotic activity in treated animals. Thus, it can be concluded that the developed intranasal ASP-MNE could be used as an effective and safe tool for brain targeting of ASP in the treatment of psychotic disorders.

Matched MeSH terms: Rats, Wistar
Tocotrienols Stimulate Insulin Secretion of Rat Pancreatic Isolated Islets in a Dynamic Culture

Chia LL, Jantan I, Chua KH

Curr Pharm Biotechnol, 2017;18(7):560-568.
PMID: 28786357 DOI: 10.2174/1389201018666170808144703

BACKGROUND: Tocotrienols (T3) are the naturally occurring vitamin E derivatives that possess antioxidant properties and therapeutic potential in diabetic complications. The bioactivities of the derivatives are determined by the number and arrangement of methyl substitution on the structure.
OBJECTIVE: The objective of this study was to determine the effects of T3 derivatives, σ-T3, γ-T3 and α-T3 on insulin secretion of rat pancreatic islets in a dynamic culture.
METHOD: Pancreatic islets isolated from male Wistar rats were treated with T3 for 1 h at 37°C in a microfluidic system with continuous operation that provided a stable cell culture environment. Glucose (2.8 mM and 16.7 mM, as basal and stimulant, respectively) and potassium chloride (KCl) (30 mM) were added to the treatment in calcium free medium. The supernatant was collected for insulin measurements.
RESULTS: Short-term exposure (1 h) of σ-T3 to β cells in the stimulant glucose condition significantly potentiated insulin secretion in a dose-dependent manner. γ-T3 and α-T3 also displayed dosedependent effect but were less effective in the activation of insulin secretion. Essentially, KCl, a pancreatic β cell membrane depolarizing agent, added into the treatment further enhanced the insulin secretion of σ-T3, γ-T3 and α-T3 with ED50 values of 504, 511 and 588 µM, respectively.
CONCLUSION: The findings suggest the potential of σ-T3 in regulating glucose-stimulated insulin secretion (GSIS) in response to the intracellular calcium especially in the presence of KCl.

Matched MeSH terms: Rats, Wistar
Biocompatible and mucoadhesive bacterial cellulose-g-poly(acrylic acid) hydrogels for oral protein delivery

Ahmad N, Amin MC, Mahali SM, Ismail I, Chuang VT

Mol Pharm, 2014 Nov 3;11(11):4130-42.
PMID: 25252107 DOI: 10.1021/mp5003015

Stimuli-responsive bacterial cellulose-g-poly(acrylic acid) hydrogels were investigated for their potential use as an oral delivery system for proteins. These hydrogels were synthesized using electron beam irradiation without any cross-linking agents, thereby eliminating any potential toxic effects associated with cross-linkers. Bovine serum albumin (BSA), a model protein drug, was loaded into the hydrogels, and the release profile in simulated gastrointestinal fluids was investigated. Cumulative release of less than 10% in simulated gastric fluid (SGF) demonstrated the potential of these hydrogels to protect BSA from the acidic environment of the stomach. Subsequent conformational stability analyses of released BSA by SDS-PAGE, circular dichroism, and an esterase activity assay indicated that the structural integrity and bioactivity of BSA was maintained and preserved by the hydrogels. Furthermore, an increase in BSA penetration across intestinal mucosa tissue was observed in an ex vivo penetration experiment. Our fabricated hydrogels exhibited excellent cytocompatibility and showed no sign of toxicity, indicating the safety of these hydrogels for in vivo applications.

Matched MeSH terms: Rats, Wistar
Antioxidant profiles of a prepared extract of Chinese herbs for the treatment of atopic eczema

Chung LY

Phytother Res, 2008 Apr;22(4):493-9.
PMID: 18338748 DOI: 10.1002/ptr.2350

A standardized mixture of Chinese herbs, Zemaphyte taken orally as a daily decoction has been shown to be effective in the treatment of atopic eczema. This study showed that Zemaphyte is an efficient antioxidant, being capable of scavenging both superoxide and hydroxyl, and preventing peroxidation of biological membranes. It does not degrade hydrogen peroxide directly, but instead most likely forms a Zemaphyte-hydrogen peroxide complex. The complexed hydrogen peroxide can then be degraded in the presence of catalase to form oxygen and water. It is conceivable that Zemaphyte may contribute to the down-regulation of the activities of cells implicated in atopic eczema through its antioxidant activities.

Matched MeSH terms: Rats, Wistar
Methyl Gallate Attenuates Doxorubicin-Induced Cardiotoxicity in Rats by Suppressing Oxidative Stress

Ahmed AZ, Satyam SM, Shetty P, D'Souza MR

Scientifica (Cairo), 2021;2021:6694340.
PMID: 33510932 DOI: 10.1155/2021/6694340

Doxorubicin-induced cardiotoxicity is the leading cause of morbidity and mortality among cancer survivors. The present study was aimed to investigate the cardioprotective potential of methyl gallate; an active polyphenolic nutraceutical, against doxorubicin-induced cardiotoxicity in Wistar rats. Twenty-four female Wistar rats (150-200 g) were divided into four groups (n = 6) which consist of normal control (group I), doxorubicin control (group II), test-A (group III), and test-B (group IV). Group III and group IV animals were prophylactically treated with methyl gallate 150 mg/kg/day and 300 mg/kg/day orally, respectively, for seven days. Doxorubicin (25 mg/kg; single dose) was administered through an intraperitoneal route to group II, III, and IV animals on the seventh day to induce acute cardiotoxicity. On the 8th day, besides ECG analysis, serum CK, CK-MB, LDH, AST, MDA, and GSH were assayed. Following gross examination of isolated hearts, histopathological evaluation was performed by light microscopy. A significant (p Wistar rats by suppressing oxidative stress. Our study opens the perspective to clinical studies for consideration of methyl gallate as a potential chemoprotectant nutraceutical in the combination chemotherapy with doxorubicin to limit its cardiotoxicity.

Matched MeSH terms: Rats, Wistar
Tamoxifen induced multinucleated cells (symplasts) and distortion of seminiferous tubules in rat testis

D'Souza UJ

Asian J Androl, 2003 Sep;5(3):217-20.
PMID: 12937805

To evaluate the effect of tamoxifen citrate on male reproductive system of rat.

Matched MeSH terms: Rats, Wistar
Fulltext Toxic effects of 5-Fluorouracil on sperm count in wistar rats

D'Souza UJ

Malays J Med Sci, 2003 Jan;10(1):43-5.
PMID: 23365499 MyJurnal

The antimetabolite, 5-fluorouracil is widely used in the treatment of cancers. Although its toxic effects on testis causing germinal epithelial sloughing, tubular atrophy and generation of multinucleated cells were reported, its effect on spermatogenesis has not been studied. Hence the present study was conducted to evaluate the effects of 5-fluorouracil on epididymal sperm count. Male Wistar rats were employed in the study (n=5 per group). The animals were injected (i.p) with five consecutive doses of 5-fluorouracil (10, 20, 30mg/kg b.w) at an interval of 24h and the control with 0.1ml-distilled water. Samples were obtained at 14, 35, 42 and 70 days after injection. Rats were sacrificed, a laparatomy was performed and epididymes were collected in 1ml phosphate buffered saline (pH 7.2), minced, filtered and stained with 1% aqueous eosin Y. An aliquot was taken in leucocyte pipette, diluted with phosphate buffered saline and sperm count was done as per the standard procedure. Data were analyzed by Mann Whitney U test. The results of this study revealed that 5 - fluorouracil significantly decreased the sperm count in a dose- and time-dependent manner.

Matched MeSH terms: Rats, Wistar
Fulltext Effects of Aging and Tocotrienol-Rich Fraction Supplementation on Brain Arginine Metabolism in Rats

Mazlan M, Hamezah HS, Taridi NM, Jing Y, Liu P, Zhang H, et al.

Oxid Med Cell Longev, 2017;2017:6019796.
PMID: 29348790 DOI: 10.1155/2017/6019796

Accumulating evidence suggests that altered arginine metabolism is involved in the aging and neurodegenerative processes. This study sought to determine the effects of age and vitamin E supplementation in the form of tocotrienol-rich fraction (TRF) on brain arginine metabolism. Male Wistar rats at ages of 3 and 21 months were supplemented with TRF orally for 3 months prior to the dissection of tissue from five brain regions. The tissue concentrations of L-arginine and its nine downstream metabolites were quantified using high-performance liquid chromatography and liquid chromatography tandem mass spectrometry. We found age-related alterations in L-arginine metabolites in the chemical- and region-specific manners. Moreover, TRF supplementation reversed age-associated changes in arginine metabolites in the entorhinal cortex and cerebellum. Multiple regression analysis revealed a number of significant neurochemical-behavioral correlations, indicating the beneficial effects of TRF supplementation on memory and motor function.

Matched MeSH terms: Rats, Wistar
A novel rat model of Alzheimer's disease based on lentiviral-mediated expression of mutant APP

Parsi S, Pandamooz S, Heidari S, Naji M, Morfini G, Ahmadiani A, et al.

Neuroscience, 2015 Jan 22;284:99-106.
PMID: 25270904 DOI: 10.1016/j.neuroscience.2014.09.045

Alzheimer's disease (AD) is characterized by progressive and irreversible cognitive and memory impairment. The discovery of familial forms of AD (fAD) in association with specific gene mutations facilitated the generation of numerous rodent models. These models in turn proved valuable for the study of molecular mechanisms underlying AD pathogenesis, and facilitated translational research and preclinical drug development. This study aimed to introduce a new rat model of AD simulating some aspects of the sporadic cases of disease.

Matched MeSH terms: Rats, Wistar
Fingolimod affects gene expression profile associated with LPS-induced memory impairment

Omidbakhsh R, Rajabli B, Nasoohi S, Khallaghi B, Mohamed Z, Naidu M, et al.

Exp Brain Res, 2014 Nov;232(11):3687-96.
PMID: 25098558 DOI: 10.1007/s00221-014-4052-4

Lipopolysaccharide is an endotoxin to induce sickness behavior in several animal models to explore the link between immune activation and cognition. Neuroinflammation playing a pivotal role in disease progress is evidently influenced by sphingosine-1-phosphate. As one of the sphingosine analogs in clinical use for multiple sclerosis, fingolimod (FTY720) was shown to substantially affect gene expression profile in the context of AD in our previous experiments. The present study was designed to evaluate the drug efficacy in the context of the mere inflammatory context leading to memory impairment. FTY720 was repeatedly administered for a few days before or after intracerebral lipopolysaccharide (LPS) injection in rats. Animal's brains were then assigned to histological as well as multiplex mRNA assay following memory performance test. Both FTY720 pre-treatment and post-treatment were similarly capable of ameliorating LPS-induced memory impairment as assessed by passive avoidance test. Such amending effects may be partly accountable by the concomitant alterations in transcriptional levels of mitogen-activated protein kinases as well as inflammatory genes determined by QuantiGene Plex analysis. These findings confirming FTY720 application benefits suggest its efficacy may not differ significantly while considered either as a preventive or as a therapeutic approach against neuroinflammation.

Matched MeSH terms: Rats, Wistar
Fulltext Freeze-Dried Lopinavir-Loaded Nanostructured Lipid Carriers for Enhanced Cellular Uptake and Bioavailability: Statistical Optimization, in Vitro and in Vivo Evaluations

Khan AA, Mudassir J, Akhtar S, Murugaiyah V, Darwis Y

Pharmaceutics, 2019 Feb 25;11(2).
PMID: 30823545 DOI: 10.3390/pharmaceutics11020097

Nanostructured lipid carriers (NLCs) loaded with lopinavir (LPV) were prepared by the high-shear homogenization method. The LPV-NLCs formulations were freeze-dried using trehalose as a cryoprotectant. In vitro release studies in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8) showed a burst release. The optimized freeze-dried formulation (LPV-NLC-7-Tres) had a particle size (PS), polydispersity index (PdI), zeta potential (ZP) and % entrapment efficiency (%EE) of 286.8 ± 1.3 nm, 0.413 ± 0.017, -48.6 ± 0.89 mV and 88.31 ± 2.04%, respectively. The optimized formulation observed by transmission and scanning electron microscopes showed a spherical shape. Differential scanning calorimetry study revealed the absence of chemical interaction between the drug and lipids. In vitro cellular uptake study using Caco-2 cell line showed a higher LPV uptake from LPV-NLC-7-Tres formulation compared to the free LPV-suspension. The 6-month stability study showed a minimum rise of ~40 nm in PS, while no significant changes in PdI, ZP and drug content of the LPV-NLC-7-Tres formulation stored at 5 °C ± 3 °C. The bioavailability of LPV following oral administration of LPV-NLC-7-Tres in male Wistar rats was found 6.98-fold higher than the LPV-suspension. In conclusion, the nanostructure lipid carriers are potential carriers for improving the oral bioavailability of lopinavir.

Matched MeSH terms: Rats, Wistar
Amnesic effects of electroshock and anoxia on conditioned taste aversion learning in rats

Banerjee U, Das P

Behav Processes, 1977 Jun;2(2):175-86.
PMID: 24896436 DOI: 10.1016/0376-6357(77)90019-5

Albino Wistar rats of both sexes were given a conditioned taste aversion training (CTA). Saccharin was used as the conditional stimulus (CS) and apomorphine-induced illness as the unconditional stimulus (US) on day 4. Amnestic treatment with electroconvulsive shock (ECS) or nitrogen anoxia were given to the rats at various points within the 180-min long CS-US interval as well as after the US. They were reexposed to the CS on days 5 and 6 in order to evaluate CTA and its extinction respectively. Apomorphine injection alone produced significant CTA as long as the CS-US interval was less than 120 min but not beyond it. Saline injections, with or without amnestic treatments, produced only an adaptation to and preference for saccharin. ECS could prevent CTA when delivered within 85 min before or 110 min after the US. Anoxia was effective at a much shorter range of time than ECS. The results are discussed in the perspectives of neophobia, saccharin aversion, amnestic agents and the character as well as gradients of amnesia produced.

Matched MeSH terms: Rats, Wistar
Pulmonary oedema due to inhalation of detergent aerosol

Rao J, Das PK

Malays J Pathol, 1994 Dec;16(2):165-6.
PMID: 9053567

Healthy adult male albino rats were subjected to inhalation of increasing doses of detergent (dioctyl sodium sulfo-succinate) aerosol ranging from 100 mg to 500 mg. Administration of 500 mg of detergent aerosol resulted in peribronchial and focal alveolar oedema in 3 out of 5 animals. The lungs of control animals which were subjected to inhalation of vehicle aerosol (ethanol and saline) did not show any abnormality. It is possible that pulmonary oedema observed in detergent aerosol inhalation may be due to the action of detergents on the surfactant system of the lung.

Matched MeSH terms: Rats, Wistar
Immunosuppressive Effects of Annona muricata L. Leaf Extract on Cellular and Humoral Immune Responses in Male Wistar Rats

Abdul Wahab SM, Husain K, Jantan I, Arshad L, Haque MA, Mohd Fauzi N, et al.

Curr Pharm Biotechnol, 2023;24(11):1465-1477.
PMID: 36545731 DOI: 10.2174/1389201024666221221113020

BACKGROUND: Annona muricata L. (Annonaceae) (AM)'s remarkable anti-inflammatory and anti-cancer activities make it a targeted plant to be explored for its immunomodulatory properties. Traditional practitioners have employed various components of AM to cure a variety of ailments, including cancer, diabetes, and inflammation.
OBJECTIVE: The present study evaluated the immunosuppressive effects of 80% ethanol extract of of AM leaves in male Wistar rats on different parameters of humoral and cellular immune responses.
METHODS: AM leaf extract (AMLE) was analyzed using UHPLC-MS/MS to profile its secondary metabolites. AMLE was rich in polyphenols which include (epi)catechin-(epi)catechin-(epi) catechin, caffeic acid, coumaroylquinic acid, hyperin, kaempferol, quinic acid and rutin. The rats were administered 100, 200 and 400 mg/kg bw of the extract daily for 14 days. The effects of AMLE on innate immune responses were determined by evaluating phagocytosis, neutrophils migration, reactive oxygen species (ROS) release, CD11b/CD18 integrin expression, and ceruloplasmin, lysozyme and myeloperoxidase (MPO) levels. The adaptive immune parameters were evaluated by immunizing the rats with sheep red blood cells (sRBC) on day 0 and administered orally with AMLE for 14 days.
RESULTS: AMLE established significant immunosuppressive effects on the innate immune parameters by inhibiting the neutrophil migration, ROS production, phagocytic activity and expression of CD11b/CD18 integrin in a dose-dependent pattern. AMLE also suppressed ceruloplasmin, MPO and lysozyme expressions in the rat plasma dose-dependently. AMLE dose-dependently inhibited T and B lymphocytes proliferation, Th1 and Th2 cytokine production, CD4+ and CD8+ co-expression in splenocytes, immunoglobulins (IgM and IgG) expression and the sRBC-induced swelling rate of rat paw in delayed-type hypersensitivity (DTH).
CONCLUSION: The strong inhibitory effects on the different parameters of humoral and cellular responses indicate that AMLE has potential to be an important source of effective immunosuppressive agents.

Matched MeSH terms: Rats, Wistar
Light-Emitting Diode (LED) Therapy Attenuates Neurotoxicity of Methanol-Induced Memory Impairment and Apoptosis in The Hippocampus

Ghanbari A, Zibara K, Salari S, Ghareghani M, Rad P, Mohamed W, et al.

CNS Neurol Disord Drug Targets, 2018;17(7):528-538.
PMID: 29968547 DOI: 10.2174/1871527317666180703111643

BACKGROUND & OBJECTIVE: The adolescent brain has a higher vulnerability to alcoholinduced neurotoxicity, compared to adult's brain. Most studies have investigated the effect of ethanol consumption on the body, however, methanol consumption, which peaked in the last years, is still poorly explored.
METHOD: In this study, we investigated the effects of methanol neurotoxicity on memory function and pathological outcomes in the hippocampus of adolescent rats and examined the efficacy of Light- Emitting Diode (LED) therapy. Methanol induced neurotoxic rats showed a significant decrease in the latency period, in comparison to controls, which was significantly improved in LED treated rats at 7, 14 and 28 days, indicating recovery of memory function. In addition, methanol neurotoxicity in hippocampus caused a significant increase in cell death (caspase3+ cells) and cell edema at 7 and 28 days, which were significantly decreased by LED therapy. Furthermore, the number of glial fibrillary acid protein astrocytes was significantly lower in methanol rats, compared to controls, whereas LED treatment caused their significant increase. Finally, methanol neurotoxicity caused a significant decrease in the number of brain-derived neurotrophic factor (BDNF+) cells, but also circulating serum BDNF, at 7 and 28 days, compared to controls, which were significantly increased by LED therapy. Importantly, LED significantly increased the number of Ki-67+ cells and BDNF levels in the serum and hypothalamus in control-LED rats, compared to controls without LED therapy.
CONCLUSION: In conclusion, chronic methanol administration caused severe memory impairments and several pathological outcomes in the hippocampus of adolescent rats which were improved by LED therapy.

Matched MeSH terms: Rats, Wistar
Cardiovascular autonomic effects of transcutaneous auricular nerve stimulation via the tragus in the rat involve spinal cervical sensory afferent pathways

Mahadi KM, Lall VK, Deuchars SA, Deuchars J

Brain Stimul, 2019 05 06;12(5):1151-1158.
PMID: 31129152 DOI: 10.1016/j.brs.2019.05.002

BACKGROUND: Electrical stimulation on select areas of the external auricular dermatome influences the autonomic nervous system. It has been postulated that activation of the Auricular Branch of the Vagus Nerve (ABVN) mediates such autonomic changes. However, the underlying neural pathways mediating these effects are unknown and, further, our understanding of the anatomical distribution of the ABVN in the auricle has now been questioned.
OBJECTIVE: To investigate the effects of electrical stimulation of the tragus on autonomic outputs in the rat and probe the underlying neural pathways.
METHODS: Central neuronal projections from nerves innervating the external auricle were investigated by injections of the transganglionic tracer cholera toxin B chain (CTB) into the right tragus of Wistar rats. Physiological recordings of heart rate, perfusion pressure, respiratory rate and sympathetic nerve activity were made in an anaesthetic free Working Heart Brainstem Preparation (WHBP) of the rat and changes in response to electrical stimulation of the tragus analysed.
RESULTS: Neuronal tracing from the tragus revealed that the densest CTB labelling was within laminae III-IV of the dorsal horn of the upper cervical spinal cord, ipsilateral to the injection sites. In the medulla oblongata, CTB labelled afferents were observed in the paratrigeminal nucleus, spinal trigeminal tract and cuneate nucleus. Surprisingly, only sparse labelling was observed in the vagal afferent termination site, the nucleus tractus solitarius. Recordings made from rats at night time revealed more robust sympathetic activity in comparison to day time rats, thus subsequent experiments were conducted in rats at night time. Electrical stimulation was delivered across the tragus for 5 min. Direct recording from the sympathetic chain revealed a central sympathoinhibition by up to 36% following tragus stimulation. Sympathoinhibition remained following sectioning of the cervical vagus nerve ipsilateral to the stimulation site, but was attenuated by sectioning of the upper cervical afferent nerve roots.
CONCLUSIONS: Inhibition of the sympathetic nervous system activity upon electrical stimulation of the tragus in the rat is mediated at least in part through sensory afferent projections to the upper cervical spinal cord. This challenges the notion that tragal stimulation is mediated by the auricular branch of the vagus nerve and suggests that alternative mechanisms may be involved.

Matched MeSH terms: Rats, Wistar
Amiodarone-induced phospholipidosis: an in vivo [14C]-acetate uptake study in rat

Sirajudeen KN, Gurumoorthy P, Devaraj H, Devaraj SN

Drug Chem Toxicol, 2002 Aug;25(3):247-54.
PMID: 12173246

Amiodarone (AD), a potent antiarrhythmic drug, is often associated with several adverse effects. It is shown to accumulate phospholipids in various tissues, and the impaired catabolism of phospholipids has been implicated in AD-induced phospholipidosis. The synthesis of phospholipids in tissues has not been dealt with. Hence, the incorporation of [14C]-acetate into phospholipids has been studied to understand the AD-induced phospholipidosis in lung and liver. A significant increase in lung and liver phospholipids was observed after 21 and 28 days of AD (175 mg/kg body weight/day) treatment. In the lung and liver, the incorporation of [14C]-acetate into all phospholipid fractions was elevated, while in the lung mitochondria phosphatidylcholine, phosphatidyl ethanolamine and the cardiolipin levels were significantly increased. The results indicate that, in addition to the impaired catabolism of phospholipid, AD treatment resulted in increased phospholipid synthesis.

Matched MeSH terms: Rats, Wistar

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links