ABSTRACT
BACKGROUND: Male reproductive functions are regulated in the hypothalamic-pituitary-gonadal (HPG) axis. Any problem in this axis would lead to the deterioration of reproductive functions. The present study aimed to investigate the effects of intracerebroventricular (icv) Spexin (SPX) infusion on the HPG axis in detail. METHODS: 40 Wistar albino rats were divided into four groups: control, sham, SPX 30 nmol and SPX 100 nmol (n=10). 30 nmol/1⯵l/hour SPX was administered icv to the rats in the SPX 30 nmol group for 7 days, while rats in the SPX 100 nmol group were administered 100 nmol/1⯵l/hour SPX. On the 7th day, the rats were decapitated, blood and tissue samples were collected. Serum LH, FSH and testosterone levels were determined with the ELISA method, GnRH mRNA expression level was determined in hypothalamus with the RT-PCR method. Seminiferous tubule diameter and epithelial thickness were determined with the hematoxylin-eosin staining method. RESULTS: SPX infusion was increased GnRH mRNA expression in the hypothalamus tissue independent of the dose (p<0.05). Serum LH, FSH and testosterone levels in the SPX groups were increased when compared to the control and sham groups independent of the dose (p <0.05). Histological analysis revealed that SPX infusion did not lead to any changes in seminiferous epithelial thickness, while the tubule diameter increased in the SPX groups (p<0.05). CONCLUSION: The study findings demonstrated that icv SPX infusion stimulated the HPG axis and increased the secretion of male reproductive hormones.
Subject(s)
Follicle Stimulating Hormone , Gonadotropin-Releasing Hormone , Hypothalamo-Hypophyseal System , Luteinizing Hormone , Peptide Hormones , Rats, Wistar , Testis , Testosterone , Animals , Male , Rats , Testis/drug effects , Testis/metabolism , Hypothalamo-Hypophyseal System/drug effects , Hypothalamo-Hypophyseal System/metabolism , Testosterone/blood , Luteinizing Hormone/blood , Peptide Hormones/administration & dosage , Peptide Hormones/metabolism , Follicle Stimulating Hormone/blood , Gonadotropin-Releasing Hormone/metabolism , Injections, Intraventricular , Hypothalamus/drug effects , Hypothalamus/metabolism , Infusions, Intraventricular , RNA, Messenger/metabolismABSTRACT
AIM: The hypothesis of this study is to determine the effects of intracerebroventricular (icv) prokineticin 2 infusion on food consumption and body weight and to elucidate whether it has effects on energy expenditure via the hypothalamus-pituitary-thyroid (HPT) axis in adipose tissue. MATERIAL AND METHODS: A total of 40 rats were used in the study and 4 groups were established: Control, Sham, Prokineticin 1.5 and Prokineticin 4.5 (n=10). Except for the Control group, rats were treated intracerebroventricularly via osmotic minipumps, the Sham group was infused with aCSF (vehicle), and the Prokineticin 1.5 and Prokineticin 4.5 groups were infused with 1.5 nMol and 4.5 nMol prokineticin 2, respectively. Food and water consumption and body weight were monitored during 7-day infusion in all groups. At the end of the infusion, the rats were decapitated and serum TSH, fT4 and fT3 levels were determined by ELISA. In addition, PGC-1α and UCP1 gene expression levels in white adipose tissue (WAT) and brown adipose tissue (BAT), TRH from rat hypothalamic tissue were determined by real-time PCR. RESULTS: Icv prokineticin 2 (4.5 nMol) infusion had no effect on water consumption but reduced daily food consumption and body weight (p<0.05). Icv prokineticin 2 (4.5 nMol) infusion significantly increased serum TSH, fT4 and fT3 levels when compared to Control and Sham groups (p<0.05). Also, icv prokineticin 2 (4.5 nMol) infusion increased the expression of TRH in the hypothalamus tissue and expression of PGC-1α UCP1 in the WAT and BAT (p<0.05). CONCLUSION: Icv prokineticin 2 (4.5 nMol) infusion may suppress food consumption via its receptors in the hypothalamus and reduce body weight by stimulating energy expenditure and thermogenesis in adipose tissue through the HPT axis.
Subject(s)
Body Weight , Eating , Energy Metabolism , Gastrointestinal Hormones , Infusions, Intraventricular , Thyroid Gland , Animals , Energy Metabolism/drug effects , Energy Metabolism/physiology , Male , Body Weight/drug effects , Eating/drug effects , Eating/physiology , Thyroid Gland/drug effects , Thyroid Gland/metabolism , Rats , Gastrointestinal Hormones/metabolism , Gastrointestinal Hormones/administration & dosage , Uncoupling Protein 1/metabolism , Hypothalamo-Hypophyseal System/drug effects , Hypothalamo-Hypophyseal System/metabolism , Neuropeptides/metabolism , Neuropeptides/administration & dosage , Thyrotropin/blood , Thyrotropin/metabolism , Adipose Tissue, Brown/metabolism , Adipose Tissue, Brown/drug effects , Thyroxine/blood , Thyroxine/administration & dosage , Drinking/drug effects , Triiodothyronine/administration & dosage , Triiodothyronine/blood , Triiodothyronine/pharmacology , Rats, Wistar , Hypothalamus/metabolism , Hypothalamus/drug effects , Adipose Tissue, White/metabolism , Adipose Tissue, White/drug effectsABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: The traditional Chinese herbal remedy Atractylodes macrocephala Koidz is renowned for its purported gastrointestinal regulatory properties and immune-enhancing capabilities. Atractylenolide III (ATL III), a prominent bioactive compound in Atractylodes macrocephala Koidz, has demonstrated significant pharmacological activities. However, its impact on neuroinflammation, oxidative stress, and therapeutic potential concerning Alzheimer's disease (AD) remain inadequately investigated. AIM OF THE STUDY: This study aims to assess the plasma pharmacokinetics of ATL III in Sprague-Dawley (SD) rats and elucidate its neuropharmacological effects on AD via the PI3K/AKT/GSK3ß pathway. Through this research, we endeavor to furnish experimental substantiation for the advancement of novel therapeutics centered on ATL III. MATERIALS AND METHODS: The pharmacokinetic profile of ATL III in SD rat plasma was analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). AD models were induced in SD rats through bilateral intracerebroventricular (ICV) administration of streptozotocin (STZ). ATL III was administered at doses of 0.6 mg/kg, 1.2 mg/kg, and 2.4 mg/kg, while donepezil (1 mg/kg) served as control. Cognitive function assessments were conducted employing behavioral tests including the Morris Water Maze and Novel Object Recognition. Neuronal pathology and histological changes were evaluated through Nissl staining and Hematoxylin-Eosin (HE) staining, respectively. Oxidative stress levels were determined by quantifying malondialdehyde (MDA) content and total superoxide dismutase (T-SOD) activity. Molecular docking analysis was employed to explore the direct binding between ATL III and its relevant targets, followed by validation using Western blot (WB) experiments to assess the expression of p-Tau, PI3K, AKT, GSK3ß, and their phosphorylated forms. RESULTS: Within the concentration range of 5-500 ng/mL, ATL III demonstrated exceptional linearity (R2 = 0.9991), with a quantification limit of 5 ng/mL. In male SD rats, ATL III exhibited a Tmax of 45 min, a t1/2 of 172.1 min, a Cmax of 1211 ng/L, and an AUC(0-t) of 156031 ng/L*min. Treatment with ATL III significantly attenuated Tau hyperphosphorylation in intracerebroventricular-streptozotocin (ICV-STZ) rats. Furthermore, ATL III administration mitigated neuroinflammation and oxidative stress, as evidenced by reduced Nissl body loss, alleviated histological alterations, decreased MDA content, and enhanced T-SOD activity. Molecular docking analyses revealed strong binding affinity between ATL III and the target genes PI3K, AKT, and GSK3ß. Experimental validation corroborated that ATL III stimulated the phosphorylation of PI3K and AKT while reducing the phosphorylation of GSK3ß. CONCLUSIONS: Our results indicate that ATL III can mitigate Tau protein phosphorylation through modulation of the PI3K/AKT/GSK3ß pathway. This attenuation consequently ameliorates neuroinflammation and oxidative stress, leading to enhanced learning and memory abilities in ICV-STZ rats.
Subject(s)
Cognitive Dysfunction , Glycogen Synthase Kinase 3 beta , Lactones , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Sesquiterpenes , Streptozocin , Animals , Male , Rats , Cognitive Dysfunction/drug therapy , Disease Models, Animal , Glycogen Synthase Kinase 3 beta/metabolism , Lactones/pharmacology , Lactones/pharmacokinetics , Lactones/administration & dosage , Maze Learning/drug effects , Molecular Docking Simulation , Neuroprotective Agents/pharmacology , Neuroprotective Agents/pharmacokinetics , Neuroprotective Agents/administration & dosage , Oxidative Stress/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats, Sprague-Dawley , Sesquiterpenes/pharmacology , Sesquiterpenes/pharmacokinetics , Sesquiterpenes/administration & dosage , Signal Transduction/drug effectsABSTRACT
The development of multitarget opioid drugs has emerged as an attractive approach for innovative pain management with reduced side effects. In the present study, a novel hybrid peptide BNT12 containing the opioid and neurotensin (NT)-like fragments was synthesized and pharmacologically characterized. In acute radiant heat paw withdrawal test, intracerebroventricular (i.c.v.) administration of BNT12 produced potent antinociception in mice. The central antinociceptive activity of BNT12 was mainly mediated by µ-, δ-opioid receptor, neurotensin receptor type 1 (NTSR1) and 2 (NTSR2), supporting a multifunctional agonism of BNT12 in the functional assays. BNT12 also exhibited significant antinociceptive effects in spared nerve injury (SNI)-neuropathic pain, complete Freund's adjuvant (CFA)-induced inflammatory pain, acetic acid-induced visceral and formalin-induced pain after i.c.v. administration. Furthermore, BNT12 exhibited substantial reduction of acute antinociceptive tolerance, shifted the dose-response curve to the right by only 1.3-fold. It is noteworthy that BNT12 showed insignificant chronic antinociceptive tolerance at the supraspinal level. In addition, BNT12 exhibited reduced or no opioid-like side effects on conditioned place preference (CPP) response, naloxone-precipitated withdrawal response, acute hyperlocomotion, motor coordination, gastrointestinal transit, and cardiovascular responses. The present investigation demonstrated that the novel hybrid peptide BNT12 might serve as a promising analgesic candidate with limited opioid-like side effects.
Subject(s)
Neurotensin , Receptors, Neurotensin , Animals , Male , Mice , Neurotensin/analogs & derivatives , Neurotensin/pharmacology , Neurotensin/chemistry , Receptors, Neurotensin/metabolism , Receptors, Neurotensin/agonists , Analgesics/pharmacology , Analgesics/chemistry , Analgesics/administration & dosage , Analgesics, Opioid/pharmacology , Analgesics, Opioid/administration & dosage , Drug Tolerance , Pain/drug therapyABSTRACT
Lycium barbarum polysaccharide (LBP) have a certain curative effect on hypoglycemic and neuroprotective effects, but the specific mechanism is unclear and needs to be further explored. This study aimed to clarify the mechanisms of LBP in the treatment of ICV-STZ mice model of AD from the perspectives of insulin resistance, IRS1/PI3K/AKT signaling pathway, and synaptic protein expression. We used male C57BL/6J mice injected with STZ (3 mg/kg) in the lateral ventricle as an AD model. After treatment with LBP, the learning and memory abilities of ICV-STZ mice were enhanced, and the pathological changes in brain tissue were alleviated. LBP can regulate the expression of proteins related to the IRS1/PI3K/AKT signaling pathway and thereby reducing Aß deposition and tau protein phosphorylation in the brain of ICV-STZ mice. In addition, LBP also can up-regulate the expression of synaptic proteins. The results indicated that LBP played a neuroprotective role by regulating the IRS1/PI3K/AKT pathway, inhibiting tau protein hyperphosphorylation and improving the expression levels of synapse-related proteins.
Subject(s)
Alzheimer Disease , Drugs, Chinese Herbal , Insulin Receptor Substrate Proteins , Mice, Inbred C57BL , Neuronal Plasticity , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , tau Proteins , Animals , Male , Mice , Alzheimer Disease/chemically induced , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/metabolism , Brain/drug effects , Brain/metabolism , Brain/pathology , Cognition/drug effects , Disease Models, Animal , Drugs, Chinese Herbal/therapeutic use , Drugs, Chinese Herbal/pharmacology , Insulin Receptor Substrate Proteins/metabolism , Insulin Resistance , Neuronal Plasticity/drug effects , Neuroprotective Agents/therapeutic use , Neuroprotective Agents/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Streptozocin , Synapses/drug effects , tau Proteins/metabolismABSTRACT
Introduction: Metabolic dysfunctions are critical in the pathology of Alzheimer's disease. Impaired zinc homeostasis, in particular, is a significant issue in this disease that has yet to be explained. Gene expression of ZIP14 in brain tissue has been previously reported. But to date, only one study has reported reduced ZIP14 levels in aged brain tissue. We investigated how dietary zinc deprivation and supplementation impact ZIP14 levels in the cerebral cortex in rats with sporadic Alzheimer's disease (sAH) produced by intracerebroventricular streptozotocin (icv-STZ). Impaired zinc homeostasis, in particular, is a significant issue with this condition that has yet to be elucidated. Methods: Animals were divided into 5 groups in equal numbers (n=8): Sham 1 group: icv received artificial cerebrospinal fluid (aCSF); Sham 2 group: retrieved icv aCSF and intraperitoneal (ip) saline, STZ group: received 3 mg/kg icv-STZ; STZ-Zn-Deficient group: received 3 mg/kg icv-STZ and fed a zinc-deprived diet; STZ-Zn-Supplemented: It received 3 mg/kg icv-STZ and ip zinc sulfate (5 mg/kg/day ZIP 14 levels (ng/L) in cortex tissue samples taken from animals sacrificed under general anesthesia were determined by ELISA at the final stage of the experimental applications. Results: Decreased ZIP14 levels in the sporadic Alzheimer's group were severely by zinc deficiency. Zinc supplementation treated the reduction in ZIP14 levels. Conclusion: The results of the current study show that ZIP14 levels in cerebral cortex tissue, which are suppressed in the experimental rat Alzheimer model and are even more critically reduced in zinc deficiency, can be restored by zinc supplementation.
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Environment perception plays a crucial role in autonomous driving technology. However, various factors such as adverse weather conditions and limitations in sensing equipment contribute to low perception accuracy and a restricted field of view. As a result, intelligent connected vehicles (ICVs) are currently only capable of achieving autonomous driving in specific scenarios. This paper conducts an analysis of the current studies on image or point cloud processing and cooperative perception, and summarizes three key aspects: data pre-processing methods, multi-sensor data fusion methods, and vehicle-infrastructure cooperative perception methods. Data pre-processing methods summarize the processing of point cloud data and image data in snow, rain and fog. Multi-sensor data fusion methods analyze the studies on image fusion, point cloud fusion and image-point cloud fusion. Because communication channel resources are limited, the vehicle-infrastructure cooperative perception methods discuss the fusion and sharing strategies for cooperative perception information to expand the range of perception for ICVs and achieve an optimal distribution of perception information. Finally, according to the analysis of the existing studies, the paper proposes future research directions for cooperative perception in adverse weather conditions.
ABSTRACT
AIM: The present study aimed to investigate the effect of the intracerebroventricular (icv) administration of spexin on the hypothalamus-pituitary-thyroid (HPT) axis (TRH, TSH, T4 and T3 hormones) and energy expenditure (PGC-1α and UCP1 genes) in white adipose (WAT) and brown adipose tissues (BAT) in rats. Furthermore, the study aimed to determine the effects of spexin on food-water consumption and body weight of rats. MATERIAL AND METHOD: The study was conducted with 40 male rats that were divided into 4 groups: Control, Sham, Spexin 30 and Spexin 100 (n = 10). Spexin (1 µl/hour) was administered to rats other than those in the control group for 7 days with osmotic minipumps intracerebroventricularly, artificial cerebrospinal fluid (vehicle) was administered to the Sham group, and 30 nMol and 100 nMol spexin was infused to the Spexin 30 and Spexin 100 groups, respectively. Food-water consumption and body weight of the rats were monitored during the experiments. After the seven-day infusion, the rats were decapitated and serum TSH, fT4 and fT3 levels were determined with ELISA on rat blood samples. Also, TRH gene expression levels from the hypothalamus tissues and PGC-1α and UCP1 expression levels from WAT and BAT were determined by real-time PCR. FINDINGS: It was determined that icv spexin infusion reduced daily food consumption and body weight without leading to a significant change in water consumption (p < 0.05). Icv spexin infusion significantly decreased serum TSH, and increased fT4 and fT3 levels when compared to control and sham groups (p < 0.05). Moreover, icv spexin infusion increased the TRH expressions in the hypothalamus tissues and PGC-1α UCP1 in the WAT and BAT (p < 0.05). CONCLUSION: Icv Spexin infusion may have effects on food consumption and body weight as well as, thyroid hormones and energy metabolism.
Subject(s)
Thyroid Gland , Thyroxine , Rats , Male , Animals , Thyroid Gland/metabolism , Triiodothyronine , Adipocytes, Brown , Organelle Biogenesis , Hypothalamus/metabolism , Body Weight , Thyrotropin/metabolism , Thyrotropin/pharmacologyABSTRACT
Oligonucleotide therapeutics offer great promise in the treatment of previously untreatable neurodegenerative disorders; however, there are some challenges to overcome in pre-clinical studies. (1) They carry a well-established dose-related acute neurotoxicity at the time of administration. (2) Repeated administration into the cerebrospinal fluid may be required for long-term therapeutic effect. Modifying oligonucleotide formulation has been postulated to prevent acute toxicity, but a sensitive and quantitative way to track seizure activity in pre-clinical studies is lacking. The use of intracerebroventricular (i.c.v.) catheters offers a solution for repeated dosing; however, fixation techniques in large animal models are not standardized and are not reliable. Here we describe a novel surgical technique in a sheep model for i.c.v. delivery of neurotherapeutics based on the fixation of the i.c.v. catheter with a 3D-printed anchorage system composed of plastic and ceramic parts, compatible with magnetic resonance imaging, computed tomography, and electroencephalography (EEG). Our technique allowed tracking electrical brain activity in awake animals via EEG and video recording during and for the 24-h period after administration of a novel oligonucleotide in sheep. Its anchoring efficiency was demonstrated for at least 2 months and will be tested for up to a year in ongoing studies.
ABSTRACT
Cases of the respiratory syncytial virus (RSV), monkeypox virus (MPXV), and avian influenza A Virus (IAV) have increased during our current prolonged Corona Virus Disease 2019 (CoViD-19) pandemic. The rise of these viral infectious diseases may be associated or even inter-dependent with acute, latent or recurrent infection with Systemic Acute Respiratory Syndrome Corona virus-2 (SARS-CoV2). The nonsensical neologism 'tripledemic' was tentatively introduced to describe the confluent nature of these trends (epidemic comes from two Greek words: epi=on, about, demos=people; pandemic is also derived from Ancient Greek: pan=all, demos=people; but 'tripledemic' would derive from Latin triplus=three, Greek demos=people, and would at best signify 'three countries, three peoples', but certainly not the current threat of confluence of three, or perhaps more pandemics). Emerging evidence suggests that monkey pox and CoViD-19, among several other viral diseases, produce significant observable manifestations in the oral cavity. From a clinical standpoint, dentists and dental personnel may be among the first health professionals to encounter and diagnose clinical signs of converging infections. From the immune surveillance viewpoint, viral recombination and viral interference among these infectious diseases must be examined to determine the potential threat of these colliding pandemics.
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The present study was designed to evaluate the effects of DL-methionine (DL-Met) 2-hydroxy-4-(methylthio) butanoic acid (HMTBa), or S-(5'-Adenosyl)-L-methionine chloride (SAM), using feeding trial and central administration, on live performance, plasma metabolites, and the expression of feeding-related hypothalamic neuropeptides in broilers raised to a market age (35 d). Final average body weight (BW) and feed conversion ratio (FCR) from the feeding trial exceeded the performance measurements published by the primary breeder. At d35, the MTBHa group had better BW and lower feed intake, which resulted in a better FCR than the DL-Met group at 87 TSAA to lysine. At the molecular levels, the expression of hypothalamic neuropeptide (NPY) and monocarboxylate transporter (MCT) 2 did not differ between all treated groups; however, the mRNA abundances of hypothalamic MCT1 and orexin (ORX) were significantly upregulated in DL-Met- treated groups compared to the control. The ICV administration of SAM significantly reduced feed intake at all tested periods (from 30 to 180 min post injection) compared to the aCSF-treated group (control). The central administration of HMTBa increased feed intake, which reached a significant level only 60 min post administration, compared to the control group. ICV administration of DL-Met slightly increased feed intake compared to the control group, but the difference was not statistically discernable. Quantitative real-time PCR analysis showed that the hypothalamic expression of NPY, cocaine- and amphetamine-regulated transcript, MCT1, and MCT2 was significantly upregulated in the ICV-HMTBa group compared to the aCSF birds. The hypothalamic expression of the mechanistic target of rapamycin (mTOR), AMP-activated protein kinase (AMPKα1), D-amino acid oxidase, and hydroxyacid oxidase was significantly upregulated in DL-Met compared to the control group. The mRNA abundances of ORX were significantly increased in the hypothalamus of both DL-Met and HMTBa groups compared to the aCSF birds; however, mTOR gene expression was significantly downregulated in the SAM compared to the control group. Taken together, these data show, for the first time, that DL-Met and HMTBa have a common downstream (ORX) pathway, but also a differential central pathway, typically NPY-MCT for HMTBa and mTOR-AMPK for methionine.
ABSTRACT
BACKGROUND & AIM: Adiponectin is a member of the adipokine family and contributes to regulating energy homeostasis, reproduction, and various biological functions, such as insulin receptor signaling pathway sensitivity, mitochondrial biogenesis, oxidative metabolism, neurogenesis, and suppression of inflammation. This study aimed to investigate the effects of intracerebroventricular (ICV) injection of adiponectin and its interaction with the neuropeptide Y (NPY) and GABAergic systems on central appetite regulation in neonatal layer-type chickens. MATERIALS & METHODS: In this study, 6 experiments were conducted, each of which included 4 experimental groups. In the first experiment, the chickens were injected with saline and adiponectin (20.73, 41.45, and 62.18 nmol). In the second experiment, saline, adiponectin (62.18 nmol), B5063 (NPY1 receptor antagonist, 2.12 nmol), and simultaneous injections of adiponectin and B5063 were performed. Experiments 3 to 6 were done in the same way to experiment 1, but the chickens were injected with SF22 (NPY2 receptor antagonist, 2.66 nmol), SML0891 (NPY5 receptor antagonist, 2.89 nmol), picrotoxin (GABAA receptor antagonist, 0.89 nmol), CGP54626 (GABAB receptor antagonist, 0.047 nmol) instead of B5063. Feed consumption was measured 120 min after the injection. RESULTS: A dose-dependent increase in appetite was observed after the injection of adiponectin (20.73, 41.45, and 62.18 nmol) (P < 0.05). The injection of B5063 + adiponectin attenuated the hyperphagic effect of adiponectin (P < 0.05). In addition, co-injection of picrotoxin and adiponectin significantly decreased adiponectin-induced hyperphagia (P < 0.05). In addition, adiponectin significantly increased the number of steps, jumps, exploratory food, pecks, and standing time, while decreasing sitting time and rest time (P < 0.05). CONCLUSION: These results suggest that the hyperphagic effects of adiponectin are probably mediated through NPY1 and GABAA receptors in neonatal layer-type chickens.
Subject(s)
Adiponectin , Chickens , Eating , Feeding Behavior , Neuropeptide Y , Animals , Adiponectin/metabolism , Adiponectin/pharmacology , Chickens/physiology , Feeding Behavior/physiology , Injections, Intraventricular , Neuropeptide Y/metabolism , Picrotoxin/pharmacologyABSTRACT
Melatonin is a hormone secreted by the pineal gland, it can be associated with circadian rhythms, aging and neuroprotection. Melatonin levels are decreased in sporadic Alzheimer's disease (sAD) patients, which suggests a relationship between the melatonergic system and sAD. Melatonin may reduce inflammation, oxidative stress, TAU protein hyperphosphorylation, and the formation of ß-amyloid (Aß) aggregates. Therefore, the objective of this work was to investigate the impact of treatment with 10 mg/kg of melatonin (i.p) in the animal model of sAD induced by the intracerebroventricular (ICV) infusion of 3 mg/kg of streptozotocin (STZ). ICV-STZ causes changes in the brain of rats similar to those found in patients with sAD. These changes include; progressive memory decline, the formation of neurofibrillary tangles, senile plaques, disturbances in glucose metabolism, insulin resistance and even reactive astrogliosis characterized by the upregulation of glucose levels and glial fibrillary acidic protein (GFAP). The results show that ICV-STZ caused short-term spatial memory impairment in rats after 30 days of STZ infusion without locomotor impairment which was evaluated on day 27 post-injury. Furthermore, we observed that a prolonged 30-day treatment with melatonin can improve the cognitive impairment of animals in the Y-maze test, but not in the object location test. Finally, we demonstrated that animals receiving ICV-STZ have high levels of Aß and GFAP in the hippocampus and that treatment with melatonin reduces Aß levels but does not reduce GFAP levels, concluding that melatonin may be useful to control the progression of amyloid pathology in the brain.
ABSTRACT
Mucopolysaccharidosis Type IIIB (MPS IIIB) is an ultrarare, fatal pediatric disease with no approved therapy. It is caused by mutations in the gene encoding for lysosomal enzyme alpha-N-acetylglucosaminidase (NAGLU). Tralesinidase alfa (TA) is a fusion protein comprised of recombinant NAGLU and a modified human insulin-like growth factor 2 that is being developed as an enzyme replacement therapy for MPS IIIB. Since MPS IIIB is a pediatric disease the safety/toxicity, pharmacokinetics and biodistribution of TA were evaluated in juvenile non-human primates that were administered up to 5 weekly intracerebroventricular (ICV) or single intravenous (IV) infusions of TA. TA administered by ICV slow-, ICV isovolumetric bolus- or IV-infusion was well-tolerated, and no effects were observed on clinical observations, electrocardiographic or ophthalmologic parameters, or respiratory rates. The drug-related changes observed were limited to increased cell infiltrates in the CSF and along the ICV catheter track after ICV administration. These findings were not associated with functional changes and are associated with the use of ICV catheters. The CSF PK profiles were consistent across all conditions tested and TA distributed widely in the CNS after ICV administration. Anti-drug antibodies were observed but did not appear to significantly affect the exposure to TA. Correlations between TA concentrations in plasma and brain regions in direct contact with the cisterna magna suggest glymphatic drainage may be responsible for clearance of TA from the CNS. The data support the administration of TA by isovolumetric bolus ICV infusion to pediatric patients with MPS IIIB.
ABSTRACT
Radix Rehmanniae Praeparata (RRP, Shu Dihuang in Cinese) is widely used as primal medicine in Chinese herbal formula for the treatment of Alzheimer's disease (AD). However, the underlying mechanism of RRP for AD remains unclear. The aim of this study was to investigate the therapeutic effect of RRP on intracerebroventricular injection of streptozotocin (ICV-STZ)-induced AD model mice and its potential mechanism. ICV-STZ mice were continuously gavaged with RRP for 21 days. The pharmacological effects of RRP were evaluated by behavioral tests, brain tissue H&E staining and hippocampal tau protein phosphorylation levels. The expression levels of insulin receptor (INSR), IRS-1, pSer473-AKT/AKT and pSer9-GSK-3ß/GSK-3ß proteins in hippocampal and cortical tissues were detected by Western-blot method. The 16S rRNA gene sequencing was used to analyze the changes of intestinal microbiota in mice. The compounds in RRP were analyzed by mass spectrometry and their binding ability to INSR proteins was detected by molecular docking. The results showed that RRP ameliorated cognitive dysfunction and neuronal pathological changes of brain tissue in ICV-STZ mice, reduced tau protein hyperphosphorylation, INSR, IRS-1, pSer473-AKT/AKT, and pSer9-GSK-3ß/GSK-3ß levels in hippocampal and cortical tissues. Meanwhile, RRP reversed ICV-STZ-induced dysregulation of intestinal microbiota in AD mice. Mass spectrometry analysis showed that the RRP consisted mainly of seven compounds, namely Acteoside (Verbascoside), 5-Hydroxymethyl-2-furaldehyde (5-HMF), Apigenin7-O-glucuronide, Icariin, Gallic acid, Quercetin-3ß-D-glucoside, and Geniposide. Molecular docking results further indicated that the compounds in RRP have binding ability to INSR protein and potential multiple synergistic effects. RRP ameliorates cognitive dysfunction and brain histopathological changes in AD mice. The mechanism of RRP ameliorating AD may be related to the regulation of INSR/IRS-1/AKT/GSK-3ß signaling pathway and intestinal microbiota. This study supports the potential anti-AD efficacy of RRP and initially reveals the pharmacological mechanism of RRP, providing a theoretical basis for further clinical application of RRP.
ABSTRACT
BACKGROUND: Strong opioid analgesics such as morphine alleviate moderate to severe acute nociceptive pain (e.g. post-surgical or post-trauma pain) as well as chronic cancer pain. However, they evoke many adverse effects and so there is an unmet need for opioid analgesics with improved tolerability. Recently, a prominent hypothesis has been that opioid-related adverse effects are mediated by ß-arrestin2 recruitment at the µ-opioid (MOP) receptor and this stimulated research on discovery of G-protein biassed opioid analgesics. In other efforts, opioids with MOP agonist and δ-opioid (DOP) receptor antagonist profiles are promising for reducing side effects c.f. morphine. Herein, we report on the in vivo pharmacology of a novel opioid peptide (CYX-5) that is a G-protein biassed MOP receptor agonist, DOP receptor antagonist and kappa opioid (KOP) receptor agonist. METHODS: Male Sprague-Dawley received intracerebroventricular bolus doses of CYX-5 (3, 10, 20 nmol), morphine (100 nmol) or vehicle, and antinociception (tail flick) was assessed relative to constipation (charcoal meal and castor oil-induced diarrhoea tests) and respiratory depression (whole body plethysmography). RESULTS: CYX-5 evoked naloxone-sensitive, moderate antinociception, at the highest dose tested. Although CYX-5 did not inhibit gastrointestinal motility, it reduced stool output markedly in the castor oil-induced diarrhoea test. In contrast to morphine that evoked respiratory depression, CYX-5 increased tidal volume, thereby stimulating respiration. CONCLUSION: Despite its lack of recruitment of ß-arrestin2 at MOP, DOP and KOP receptors, CYX-5 evoked constipation, implicating a mechanism other than ß-arrestin2 recruitment at MOP, DOP and KOP receptors, mediating constipation evoked by CYX-5 and potentially other opioid ligands.
Subject(s)
Constipation , Morphine , Receptors, Opioid, delta , Respiratory Insufficiency , Animals , Male , Rats , Analgesics, Opioid/adverse effects , Castor Oil/adverse effects , Constipation/chemically induced , Constipation/drug therapy , Diarrhea/drug therapy , GTP-Binding Proteins , Morphine/adverse effects , Narcotic Antagonists/pharmacology , Rats, Sprague-Dawley , Receptors, Opioid, delta/agonists , Receptors, Opioid, mu/agonists , Respiratory Insufficiency/chemically inducedABSTRACT
Alzheimer's disease (AD) is a most common and prevalent age related insidious neurological condition characterised by formation of Aß (1-42) plaques and NFT in the hippocampus. Major symptoms of AD include memory and cognitive loss caused by neuroinflammation, Aß (1-42) plaques, and NFT accumulation in the brain. Intracerebroventricular administration of STZ up-regulates the level of Aß (1-42) plaques, and NFT by activating NF-kB pathway. All animals were trained for behaviour analysis before infusion of ICV-STZ bilaterally, at a dose of 3 mg/kg; icv. The stereotaxic surgery was performed in target region with coordinates -2 mm [AP], 1.6 mm [MR], and1.5 mm [DV]. On day 1 and day 3 after surgery HS (hamilton syringe) was used to infuse STZ at the target region of brain. Morris Water Maze (MWM), and Elevated Plus Maze (EPM) tests were performed to check spatial and learning memory in all groups. ICV-STZ infusion produced memory impairment by increasing the activity of AchE, oxidative markers (LPO, GSH, and nitrite), neurotransmitters levels (AchE, GABA, and glutamate), and release of neuroinflammatory markers (NF-kB, IL-6, and IL-1ß). The treatment with Honokiol (Bioactive polyphenolic compound) significantly ameliorated the behavioural changes at a dose of 5, and 10 mg/kg; i.p on day 7, 14, and 21. After behavioural analysis rats were sacrificed on day 22, and the hippocampus tissue was collected to investigate the biochemical, neuroinflammatory, neurotransmitters, histopathological, and immunohistopathological changes. Here, we have found Honokiol significantly down regulates the Aß plaques via NF-kB inhibition and also reduced neuroinflammation in the brain of rats. Further inhibits the NF-kB expression confirmed for immunohistochemistry analysis. It was observed that Honokiol (5, and 10 mg/kg; i.p) dose-dependently ameliorated AchE level restored neurotransmitters concentrations in hippocampal region, and prevented neuronal loss confirmed from histopathology studies. We concluded that Honokiol drastically produced protective effect in AD model via antioxidant, reducing inflammation, AchE level, restoration of neurofibrillary tangles and preventing NF-kB as well as histopathological changes.
Subject(s)
Alzheimer Disease , Neuroprotective Agents , Animals , Rats , Alzheimer Disease/metabolism , Disease Models, Animal , Maze Learning , Models, Theoretical , Neuroinflammatory Diseases , Neuroprotective Agents/pharmacology , Neurotransmitter Agents/pharmacology , NF-kappa B/metabolism , Oxidative Stress , Rats, Wistar , Streptozocin , Amyloid beta-Peptides/metabolism , Peptide Fragments/metabolismABSTRACT
Metabolic dysfunction is a critical step in the etiopathogenesis of Alzheimer's disease. In this progressive neurological disorder, impaired zinc homeostasis has a key role that needs to be clarified. The aim of this study was to investigate the effect of zinc deficiency and administration on hippocampal Nogo-A receptor and osteocalcin gene expression in rats injected with intracerebroventricular streptozotocin (icv-STZ). Forty male Wistar rats were divided into 5 groups in equal numbers: Sham 1 group received icv artificial cerebrospinal fluid (aCSF); Sham 2 group received icv a CSF and i.p. saline; STZ group received 3 mg/kg icv STZ; STZ-Zn-deficient group received 3 mg/kg icv STZ and fed a zinc-deprived diet; STZ-Zn-supplemented group received 3 mg/kg icv STZ and i.p. zinc sulfate (5 mg/kg/day). Hippocampus tissue samples were taken following the cervical dislocation of the animals under general anesthesia. Nogo-A receptor and osteocalcin gene expression levels were determined by real-time-PCR method. Zinc supplementation attenuated the increase in hippocampal Nogo-A receptor gene expression, which was significantly increased in zinc deficiency. Again, zinc supplementation upregulated the intrinsic protective mechanisms of the brain by activating osteocalcin-expressing cells in the brain. The results of the study show that zinc has critical effects on Nogo-A receptor gene expression and hippocampal osteocalcin gene expression levels in the memory-sensitive rat hippocampus that is impaired by icv-STZ injection. These results are the first to examine the effect of zinc deficiency and supplementation on hippocampal Nogo-A receptor and osteocalcin gene expression in icv-STZ injection in rats.
Subject(s)
Alzheimer Disease , Zinc , Rats , Male , Animals , Streptozocin/pharmacology , Rats, Wistar , Nogo Proteins/metabolism , Nogo Proteins/pharmacology , Osteocalcin/genetics , Osteocalcin/metabolism , Zinc/pharmacology , Zinc/metabolism , Alzheimer Disease/pathology , Hippocampus/metabolism , Disease Models, Animal , Maze LearningABSTRACT
Whether head size and/or biological sex influence proxies of white matter (WM) microstructure such as fractional anisotropy (FA) and mean diffusivity (MD) remains controversial. Diffusion tensor imaging (DTI) indices are also associated with age, but there are large discrepancies in the spatial distribution and timeline of age-related differences reported. The aim of this study was to evaluate the associations between intracranial volume (ICV), sex, and age and DTI indices from WM in a population-based study of healthy individuals (n = 812) aged 50-66 in the Nord-Trøndelag health survey. Semiautomated tractography and tract-based spatial statistics (TBSS) analyses were performed on the entire sample and in an ICV-matched sample of men and women. The tractography results showed a similar positive association between ICV and FA in all major WM tracts in men and women. Associations between ICV and MD, radial diffusivity and axial diffusivity were also found, but to a lesser extent than FA. The TBSS results showed that both men and women had areas of higher and lower FA when controlling for age, but after controlling for age and ICV only women had areas with higher FA. The ICV matched analysis also demonstrated that only women had areas of higher FA. Age was negatively associated with FA across the entire WM skeleton in the TBSS analysis, independent of both sex and ICV. Combined, these findings demonstrated that both ICV and sex contributed to variation in DTI indices and emphasized the importance of considering ICV as a covariate in DTI analysis.
Subject(s)
White Matter , Male , Middle Aged , Humans , Adult , Female , White Matter/diagnostic imaging , Diffusion Tensor Imaging/methods , Organ Size , Anisotropy , Brain/diagnostic imagingABSTRACT
ABSTRACTThe deposition of ß-amyloid plaques, either due to their over-production or insufficient clearance, is an important pathological process in cognitive impairment and dementia. Icariin (ICA), a flavonoid compound extracted from Epimedium, has recently gained attention for numerous age-related diseases, such as neurodegenerative diseases. We aimed to explore the possible neuro-protective effect of ICA supplementation in colchicine-induced cognitive deficit rat model and exploring its effect on the ß-amyloid proteolytic enzymes. The study included four groups (10 rats each): normal control, untreated colchicine, colchicine + 10â mg/kg ICA, and colchicine + 30â mg/ kg ICA. Results revealed that intra-cerebro-ventricular colchicine injection produced neuronal morphological damage, ß amyloid deposition, and evident cognitive impairment in the behavioral assessment. Icariin supplementation in the two doses for 21 days attenuated neuronal death, reduced the ß amyloid levels, and improved memory consolidation. This was associated with modulation of the proteolytic enzymes (Neprilysin, Matrix Metalloproteinase-2, and insulin-degrading enzyme) concluding that ß-amyloid enzymatic degradation may be the possible therapeutic target for ICA.