ABSTRACT
The main objective of this study was to investigate the potential probiotic properties of Lacticaseibacillus rhamnosus VHProbi®M15 (M15). This study examined the effects of M15 on sucralfate-induced constipation in a mouse model. The BALB/c mice were randomly divided into four groups: the normal group (NOR) was without any treatment, while the constipation (CON), phenolphthalein (PHE), and probiotic (PRO) treatment groups were fed with sucralfate until the appearance of constipation symptoms. Afterward, the NOR and CON groups were given 1 ml saline orally every day until the end of the experiment; the PHE and PRO groups were given phenolphthalein or M15 suspension in 1 ml orally, respectively. Compared with the CON group, the fecal water content and intestinal peristalsis improved in the PRO group. Here, intake of M15 effectively attenuated sucralfate-induced constipation, recuperated colonic epithelial integrity, and increased serum levels of gastrointestinal excitatory neurotransmitters (motilin, gastrin, substance P). Analysis of the intestinal microbiota of mice by 16S rRNA metagenomic revealed an increase in the relative abundance of Bacteroides and a decrease in Sclerotinia, Verrucosa and Proteus in the PRO group. Compared with the CON group, the constipation-induced intestinal microecological changes were partially recovered in the PHE and PRO groups. These results demonstrate that M15 enhanced gastrointestinal transit and alleviated in mice with sucralfate-induced constipation.
Subject(s)
Galanin/analogs & derivatives , Lacticaseibacillus rhamnosus , Probiotics , Substance P/analogs & derivatives , Mice , Animals , Sucralfate/adverse effects , RNA, Ribosomal, 16S , Constipation/chemically induced , Constipation/drug therapy , Probiotics/pharmacology , Probiotics/therapeutic use , Phenolphthaleins/adverse effectsABSTRACT
To characterize phenotypically and genotypically an isolate of multidrug-resistant (MDR) K. pneumoniae from a patient with septicemia in a hospital in Recife-PE, Brazil, resistance and virulence genes were investigated using PCR and sequencing the amplicons, and the plasmid DNA was also sequenced. The K74-A3 isolate was resistant to all ß-lactams, including carbapenems, as well as to aminoglycosides and quinolones. By conducting a PCR analysis and sequencing, the variants blaNDM-7 associated with blaKPC-2 and the cps, wabG, fim-H, mrkD and entB virulence genes were identified. The analysis of plasmid revealed the presence of blaCTX-M15, aac(3)-IVa, aph(3')-Ia, aph(4)-Ia, aac(6')ib-cr, mph(A) and catB3, and also the plasmids IncX3, IncFIB, IncQ1, ColRNAI and ColpVC. To our knowledge, this is the first report of the blaNDM-7 gene in Recife-PE and we suggest that this variant is located in IncX3. These results alert us to the risk of spreading an isolate with a vast genetic arsenal of resistance, in addition to which several plasmids are present that favor the horizontal transfer of these genes.
Subject(s)
Klebsiella Infections , Klebsiella pneumoniae , Brazil , Drug Resistance, Multiple, Bacterial/genetics , Galanin/analogs & derivatives , Humans , Klebsiella pneumoniae/genetics , Plasmids/genetics , Sequence Analysis, DNA , Substance P/analogs & derivatives , Virulence/genetics , beta-Lactamases/geneticsABSTRACT
AIMS: Vicagrel is a novel antiplatelet drug used to mitigate clopidogrel resistance due to CYP2C19 polymorphism. This study aimed to develop a semi-mechanistic population pharmacokinetic (PopPK) model to characterize the pharmacokinetic (PK) profile of M15-2, the active metabolite of vicagrel and clopidogrel, and to evaluate the influence of CYP2C19 polymorphisms and other covariates in healthy subjects and patients with acute coronary syndrome (ACS) after oral administration. METHODS: The analysis utilized data from 213 subjects, including 178 healthy subjects and 35 patients, from five clinical trials. PopPK modeling and simulation were used to estimate PopPK parameters and evaluate the impact of covariates. RESULTS: The M15-2 PK profiles were well characterized by a model incorporating transit compartments, two-compartment parent models and two-compartment M15-2 models for both vicagrel and clopidogrel. The parameter estimates indicated the dose fraction of vicagrel that formed M15-2 was approximately 20-fold that of clopidogrel. Covariate analysis identified a significant effect of CYP2C19 on M15-2 apparent clearance (CL/F) and apparent volume of distribution (V3/F) for clopidogrel but only CL/F for vicagrel. The analysis suggested that the nonlinear PK of M15-2 for clopidogrel was due the first-step bioactivation of clopidogrel to 2-oxoclopidogrel. CONCLUSION: The model illustrated the bioactivation of vicagrel is more efficient and less dependent on CYP2C19 than that of clopidogrel. M15-2 is formed in a linear process from vicagrel, versus a nonlinear and less predictable process from clopidogrel. Advantages in both PK and pharmacogenetics suggest that vicagrel may reduce the complexity of currently recommended CYP2C19-based dosage adjustment for clopidogrel.
Subject(s)
Platelet Aggregation Inhibitors , Ticlopidine , Clopidogrel , Cytochrome P-450 CYP2C19/genetics , Cytochrome P-450 CYP2C19/metabolism , Galanin/analogs & derivatives , Humans , Phenylacetates , Platelet Aggregation Inhibitors/therapeutic use , Substance P/analogs & derivatives , ThiophenesABSTRACT
We report two cases of culture positive typhoid fever caused by ceftriaxone resistant Salmonella Typhi. Bacterial isolates from both the cases were positive for ESBL by phenotypic methods. Both patients didn't respond to ceftriaxone and were finally treated with meropenem. Screening of family members of one patient isolated a similar strain from a healthy carrier with the same antibiogram pattern. All isolates were subjected to PCR, which confirmed the presence of blaCTX-M15 ESBL gene. These two cases confirm emergence of ESBL-producing Salmonella Typhi causing Enteric Fever in India and also their presence in the gut flora of healthy carriers.
Subject(s)
Salmonella typhi , Typhoid Fever , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Ceftriaxone/therapeutic use , Galanin/analogs & derivatives , Humans , Microbial Sensitivity Tests , Salmonella , Substance P/analogs & derivatives , Treatment Failure , Typhoid Fever/diagnosis , Typhoid Fever/drug therapy , Typhoid Fever/microbiologyABSTRACT
Quorum sensing (QS), usually performed by N-acyl-homoserine lactones (AHLs) in Gram-staining-negative bacteria, plays an important role in plant-bacteria interactions. Rhizobium oryzihabitans M15 is a plant-growth-promoting rhizobacterium (PGPR) isolated from rice roots. In this study, we found a QS system in the endogenous plasmid of R. oryzihabitans M15 and detected the activity of AHLs by a bioassay method. We identified five AHL analogues in R. oryzihabitans M15 using liquid chromatography-tandem mass spectrometry (LC-MS). The most dominant AHL analogue was N-(3R-hydroxy-7-cis-tetradecanoyl)-l-homoserine lactone according to nuclear magnetic resonance (NMR) and Mosher's reactions. Furthermore, the rosI mutant abolished AHL production and significantly decreased growth, exopolysaccharide (EPS) production, biofilm formation, and motility compared to the wild-type strain. These results lay the foundation for further investigating the QS regulation mechanism and signal pathway of R. oryzihabitans M15 and its interactions with the host plant.
Subject(s)
Acyl-Butyrolactones , Rhizobium , Galanin/analogs & derivatives , Quorum Sensing , Rhizobium/genetics , Signal Transduction , Substance P/analogs & derivativesABSTRACT
Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease. Neuronal apoptosis plays an important pathological role in early brain injury after SAH. Galanin receptor 1 (GalR1) activation was recently shown to be anti-apoptotic in the setting of ischemic stroke. This study aimed to explore the anti-neuronal apoptosis effect of GalR1 activation after SAH, as well as the underlying mechanisms. GalR1 CRISPR and GalR1 selective agonist, M617, was administered, respectively. Extracellular-signal-regulated kinase (ERK) inhibitor (U0126) and glycogen synthase kinase 3-beta (GSK3-ß) CRISPR were administered to investigate the involvement of the ERK/GSK3-ß pathway in GalR1-mediated neuroprotection after SAH. Outcome assessments included neurobehavioral tests, western blot, and immunohistochemistry. The results showed that endogenous ligand galanin (Gal) and GalR1 were markedly increased in the ipsilateral brain hemisphere at 12 h and 24 h after SAH. GalR1 were expressed mainly in neurons, but expression was also observed in some astrocytes and microglia. GalR1 CRISPR knockdown exacerbated neurological deficits and neuronal apoptosis 24 h after SAH. Moreover, activation of GalR1 with M617 significantly improved short- and long-term neurological deficits but decreased neuronal apoptosis after SAH. Furthermore, GalR1 activation dysregulated the protein levels of phosphorylated ERK and GSK-3ß, but downregulated the phosphorylated Tat-interactive protein 60 (TIP60) and cleaved caspase-3 at 24 h after SAH. GalR1 CRISPR, U0126, and GSK-3ß CRISPR abolished the beneficial effects of GalR1 activation at 24 h after SAH in rats. Collectively, the present study demonstrated that activation of GalR1 using M617 attenuated neuronal apoptosis through the ERK/GSK-3ß/TIP60 pathway after SAH in rats. GalR1 may serve as a promising therapeutic target for SAH patients.
Subject(s)
Bradykinin/analogs & derivatives , Galanin/analogs & derivatives , Glycogen Synthase Kinase 3 beta/metabolism , Lysine Acetyltransferase 5/metabolism , Neurons/metabolism , Peptide Fragments/therapeutic use , Receptor, Galanin, Type 1/metabolism , Subarachnoid Hemorrhage/metabolism , Animals , Apoptosis/drug effects , Apoptosis/physiology , Bradykinin/pharmacology , Bradykinin/therapeutic use , Drug Administration Routes , Galanin/pharmacology , Galanin/therapeutic use , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Male , Neurons/drug effects , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Peptide Fragments/pharmacology , Rats , Rats, Sprague-Dawley , Receptor, Galanin, Type 1/agonists , Subarachnoid Hemorrhage/drug therapyABSTRACT
Due to their potent immune stimulation, tumor necrosis factor alpha (TNFα) variants with tumor-homing activity are attractive as novel antitumor drugs. The promising antitumor effect of NGR-TNFα in clinical trials triggered extensive interest in developing novel tumor-homing TNFα variants in recent years. Owing to its promising antitumor effect, NGR-TNFα is usually used as a control for newly developed tumor-homing TNFα variants. In our previous works, we produced a pericyte-targeting Z-TNFα at high levels using the Escherichia coli (E. coli) M15-pQE30 system. To further compare Z-TNFα and NGR-TNFα, we attempted to express NGR-TNFα using the same system. Surprisingly, native NGR-TNFα was expressed at a low (~ 0.2 mg/L) level in E. coli M15 containing the pQE30 plasmid. However, a single nucleotide mutation of C to G, resulting in a substitution of leucine (L) with valine (V) at the start of TNFα, increased the expression of NGR-TNFα by ~ 100 times through improving transcription. In addition, the amino acid substitution showed a little impact on the receptor binding, in vitro cytotoxicity, and in vivo antitumor effect of NGR-TNFα. As fusing NGR to the N-terminus of TNFα with a valine substitution did not reduce the protein yield, the TNFα gene with a C > G mutation might be used to prepare novel tumor-homing TNFα when the native TNFα-based variant is expressed at an extremely low level in E. coli. Notably, in addition to the mutated valine, the impact of N-terminal additional amino acids provided by pQE30 vector on the function of TNFα variant must be carefully evaluated. KEY POINTS : ⢠A single nucleotide mutation increased the expression of NGR-TNFα by two orders. ⢠Nucleotide mutation-induced amino acid substitution did not reduce NGR-TNFα activity.
Subject(s)
Escherichia coli , Tumor Necrosis Factor-alpha , Cell Line, Tumor , Escherichia coli/genetics , Galanin/analogs & derivatives , Mutation , Nucleotides , Oligopeptides/genetics , Substance P/analogs & derivatives , Transcription, Genetic , Tumor Necrosis Factor-alpha/geneticsABSTRACT
Our previous research has shown that galanin plays an antinociceptive effect via binding to galanin receptors (GalRs) in nucleus accumbens (NAc). This study focused on the involvement of GalR2 in galanin-induced antinociceptive effect in NAc of neuropathic pain rats. The chronic constriction injury of sciatic nerve (CCI) was used to mimic neuropathic pain model. The hind paw withdrawal latency (HWL) to thermal stimulation and hind paw withdrawal threshold (HWT) to mechanical stimulation were measured as the indicators of pain threshold. The results showed that 14 and 28 days after CCI, the expression of GalR2 was up-regulated in bilateral NAc of rats, and intra-NAc injection of GalR2 antagonist M871 reversed galanin-induced increases in HWL and HWT of CCI rats. Furthermore, intra-NAc injection of GalR2 agonist M1145 induced increases in HWL and HWT at day 14 and day 28 after CCI, which could also be reversed by M871. Finally, we found that M1145-induced antinociceptive effect in NAc of CCI rats was stronger than that in intact rats. These results imply that the GalR2 is activated in the NAc from day 14 to day 28 after CCI and GalR2 is involved in the galanin-induced antinociceptive effect in NAc of CCI rats.
Subject(s)
Galanin/analogs & derivatives , Neuralgia/therapy , Nucleus Accumbens/metabolism , Peptides/pharmacology , Receptor, Galanin, Type 2/metabolism , Animals , Galanin/pharmacology , Gene Expression Regulation/drug effects , Male , Rats , Rats, Sprague-Dawley , Receptor, Galanin, Type 2/genetics , Sciatic NeuropathyABSTRACT
RATIONALE: The neuropeptide galanin has been implicated in a wide range of pathological conditions in which frontal and temporal structures are compromised. It works through three subtypes of G-protein-coupled receptors. One of these, the galanin receptor 1 (Gal-R1) subtype, is densely expressed in the ventral hippocampus (vHC) and ventral prefrontal cortex (vPFC); two brain structures that have similar actions on behavioral control. We hypothesize that Gal-R1 contributes to cognitive-control mechanisms that require hippocampal-prefrontal cortical circuitry. OBJECTIVE: To examine the effect of local vHC and vPFC infusions of M617, a Gal-R1 agonist, on inhibitory mechanisms of response control. METHODS: Different cohorts of rats were implanted with bilateral guide cannulae targeting the vPFC or the vHC. Following infusion of the Gal-R1 agonist, we examined the animals' behavior using a touchscreen version of the 5-choice reaction time task (5-choice task). RESULTS: The Gal-R1 agonist produced opposing behaviors in the vPFC and vHC, leading to disruption of impulse control when infused in the vPFC but high impulse control when infused into the vHC. This contrast between areas was accentuated when we added variability to the timing of the stimulus, which led to long decision times and reduced accuracy in the vPFC group but a general improvement in performance accuracy in the vHC group. CONCLUSIONS: These results provide the first evidence of a selective mechanism of Gal-R1-mediated modulation of impulse control in prefrontal-hippocampal circuitry.
Subject(s)
Galanin/analogs & derivatives , Hippocampus/physiology , Impulsive Behavior/physiology , Prefrontal Cortex/physiology , Receptor, Galanin, Type 1/agonists , Receptor, Galanin, Type 1/physiology , Animals , Bradykinin/administration & dosage , Bradykinin/analogs & derivatives , Conditioning, Operant/drug effects , Conditioning, Operant/physiology , Dose-Response Relationship, Drug , Galanin/administration & dosage , Galanin/physiology , Hippocampus/drug effects , Impulsive Behavior/drug effects , Infusions, Intraventricular , Male , Peptide Fragments/administration & dosage , Photic Stimulation/methods , Prefrontal Cortex/drug effects , Rats , Rats, Long-Evans , Reaction Time/drug effects , Reaction Time/physiologyABSTRACT
Galanin and galanin receptors (GalRs) have been reported to be involved in the transmission and modulation of nociceptive information in the central nervous system (CNS). However, the underlying mechanism of the antinociception of GalRs in neuropathic pain remains unclear. This study investigated the antinociception induced by galanin receptor 1 (GalR1) via protein kinase A (PKA) signaling pathway in the nucleus accumbens (NAc) of rats with neuropathic pain. A mononeuropathy model was replicated by ligation of the left sciatic nerve, following which the expression of phospho-PKA (p-PKA) in the NAc were markedly up-regulated at 14(th) and 28(th) day after ligation of sciatic nerve, and p-PKA expression was down-regulated by intra-NAc injection of GalR1 agonist M617, but the GalR1 antagonist M35 did not have an effect. We also found that M35 in the NAc blocked the M617-induced increase in the hind paw withdrawal latencies (HWLs) of rats with mononeuropathy, but M35 alone had no effect on HWLs, and PKA inhibitor H-89 attenuated the M617-induced an increase in the HWLs. These results suggested that GalR1 induced an antinociception via inhibiting PKA activation, implying that GalR agonists may be potential and potent therapeutic options to treat chronic neuropathic pain.
Subject(s)
Analgesics/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Neuralgia/metabolism , Neuralgia/prevention & control , Nucleus Accumbens/metabolism , Receptor, Galanin, Type 1/biosynthesis , Animals , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Enzyme Activation/drug effects , Enzyme Activation/physiology , Galanin/analogs & derivatives , Galanin/pharmacology , Male , Nucleus Accumbens/drug effects , Pain Measurement/drug effects , Pain Measurement/methods , Peptide Fragments/pharmacology , Rats , Rats, Sprague-Dawley , Receptor, Galanin, Type 1/agonists , Receptor, Galanin, Type 1/antagonists & inhibitorsABSTRACT
Agonists and antagonists for galanin receptor subtypes GalR1-3 can be used as putative therapeutics targets for the treatment of various human diseases. However, effects of galanin and its N-terminal fragments on myocardial ischemia/reperfusion injury remain unclear. This study was designed to assess the ability of the full-length galanin (GWTLNSAGYLLGPHAIDNHRSFSDKHGLT-NH2, G1), the natural fragments WTLNSAGYLL-NH2 (G2) and WTLNSAGYLLGPHA (G3), and their modified analogs WTLNAAGYLL (G4) and WTLNSAGYLLGPßAH (G5) to limit acute myocardial infarction in rats in vivo. The peptides G2-5 were synthesized by the automatic solid phase method using Fmoc technology, purified by preparative HPLC and identified by 1H NMR spectroscopy and MALDI -TOF mass spectrometry. The peptides G1-5 were administered by i.v. bolus injection at the onset of reperfusion at doses of 0.25, 0.50, 1.0, 2.0 or 3.0â¯mg/kg. The optimal doses of the peptides G1-5 significantly reduced the infarction area and decreased the activity of CK-MB and LDH in blood plasma at the end of reperfusion compared with the control. Among the peptides studied, G5 showed high efficacy in reducing the infarct size and the activity of necrosis markers in blood plasma with no significant effect on hemodynamic parameters. The results suggest that a novel agonist for galanin receptors G5 may be a promising tool for the treatment of myocardial ischemia/reperfusion (I/R) injury. Further studies are warranted to explore the stability of this peptide in blood plasma and mechanisms that contribute to its cardioprotective effects.
Subject(s)
Galanin/analogs & derivatives , Galanin/therapeutic use , Myocardial Infarction/drug therapy , Peptides/therapeutic use , Animals , Galanin/chemistry , Male , Myocardial Infarction/blood , Myocardial Infarction/metabolism , Myocardium/metabolism , Peptides/chemistry , Rats , Rats, Wistar , Receptors, Galanin/blood , Receptors, Galanin/metabolismABSTRACT
Although recent results of our and other studies have showed that galanin (GAL) is an antidiabetic and anti-inflammatory neuropeptide, the molecular mechanism how central GAL regulates energy homeostasis and insulin sensitivity is still not fully understood. The aim of this study was to investigate whether central type 2 of GAL receptors (GALR2) are involved in the regulation of systemic glucose metabolism and its underlying mechanisms. In the present study, type 2 diabetic rats were intracerebroventricularly (i.c.v.) given 100â¯nM/kg/d GALR2 agonist M1145 or GALR2 antagonist M871 in 5⯵l artificial cerebrospinal fluid once a day for consecutive 21â¯days. Then insulin resistance indexes, inflammatory factor and many genes associated with the function of glucose metabolism were examined in peripheral tissues. The present findings showed that the intracerebroventricular injection of M1145 or M871 respectively increased or decreased glucose infusion rates in hyperinsulinemic euglycemic clamp tests, but attenuated or enhanced the plasma inflammatory factors and glucose concentration in type 2 diabetic rats. Moreover, administration of M1145 markedly increased PGC-1α and GLUT4 expression in skeletal muscles and adipocytes of type 2 diabetic rats. In conclusion, activation of central GALR2 promotes glucose metabolism and ameliorates insulin resistance mainly through the PGC-1α/GLUT4 pathways. The central GALR2 is crucial to whole-body insulin sensitivity and energy homeostasis.
Subject(s)
Diabetes Mellitus, Experimental/metabolism , Galanin/analogs & derivatives , Galanin/metabolism , Glucose/metabolism , Peptides/pharmacology , Receptor, Galanin, Type 2/metabolism , Animals , Blood Glucose , Galanin/administration & dosage , Galanin/pharmacology , Gene Expression Regulation/drug effects , Glucose Transporter Type 4/genetics , Glucose Transporter Type 4/metabolism , Infusions, Intraventricular , Insulin/metabolism , Insulin Resistance , Male , Peptides/administration & dosage , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , RatsABSTRACT
The results of our and other's studies showed that activation of galanin receptor 1 could mitigate insulin resistance via promoting glucose transporter 4 (GLUT4) expression and translocation in the skeletal muscle of rats. But no literature are available regarding the effect of galanin receptor 2 (GALR2) on insulin resistance in skeletal muscle of type 2 diabetes. Herein, in this study we intended to survey the effect of GALR2 and its signal mechanisms in the mice with high fat diet-induced obese. The mice were intraperitoneally injected with vehicle, GALR2 agonist M1145 and antagonist M871 respectively once a day for continuous 21 days. The skeletal muscles were processed for determination of glucose uptake, and GLUT4 mRNA and protein expression levels. The PGC-1α, AKT, p38MAPK, AS160, pAKT, pP38MAPK and pAS160 expression levels were quantitatively assessed too. We found that pharmacological activation of GALR2 enhanced energy expenditure, and increased GLUT4 expression and translocation in skeletal muscle of mice during high-fat diet regimens. Activation of GALR2 alleviated insulin resistance through P38MAPK/PGC-1α/GLUT4 and AKT/AS160/GLUT4 pathway in the skeletal muscle of mice. Overall, these results identify that GALR2 is a regulator of insulin resistance and activation of GALR2 represents a promising strategy against obesity-induced insulin resistance.
Subject(s)
Galanin/analogs & derivatives , Insulin Resistance , Muscle Proteins , Muscle, Skeletal/metabolism , Obesity/metabolism , Receptor, Galanin, Type 2 , Animals , Galanin/pharmacology , Glucose/metabolism , Male , Mice , Muscle Proteins/agonists , Muscle Proteins/metabolism , Muscle, Skeletal/pathology , Obesity/drug therapy , Obesity/pathology , Receptor, Galanin, Type 2/agonists , Receptor, Galanin, Type 2/metabolismABSTRACT
The present study was performed to explore the role of galanin and galanin receptor 1 (GalR 1) in nociceptive modulation in the central nucleus of amygdala (CeA) in normal rats and rats with neuropathy, and the involvement of GalR 1 and PKC was also investigated. The hindpaw withdrawal latencies (HWLs) to thermal and mechanical stimulations were increased in a dose-dependent manner after intra-CeA injection of galanin in both normal rats and rats with neuropathy. The increased HWLs were significantly attenuated by intra-CeA injection of galanin receptor antagonist M40, indicating an involvement of galanin receptor in nociceptive modulation in CeA. Furthermore, intra-CeA administration of the GalR 1 agonist M 617 induced increases in HWLs in normal rats, suggesting that GalR 1 may be involved in galanin-induce antinociception in CeA. Additionally, intra-CeA injection of the PKC inhibitor inhibited galanin-induced antinociception, showing an involvement of PKC in galanin-induced antinociception in CeA of normal rats. Moreover, there was a significant increase in GalR1 content in CeA in rats with neuropathy than that in normal rats. These results illustrated that galanin induced antinociception in CeA in normal rats and rats with neuropathy, and there is an up-regulation of GalR1 expression in rats with neuropathy.
Subject(s)
Bradykinin/analogs & derivatives , Central Amygdaloid Nucleus/metabolism , Galanin/analogs & derivatives , Galanin/antagonists & inhibitors , Neuralgia/metabolism , Nociception/drug effects , Peptide Fragments/pharmacology , Receptor, Galanin, Type 1/metabolism , Animals , Bradykinin/pharmacology , Central Amygdaloid Nucleus/pathology , Central Amygdaloid Nucleus/physiopathology , Galanin/metabolism , Galanin/pharmacology , Male , Neuralgia/drug therapy , Neuralgia/pathology , Neuralgia/physiopathology , Rats , Rats, Sprague-DawleyABSTRACT
In the present study, a halophilic Bacillus subtilis subsp. spizizenii (NCBI GenBank accession number KX109607) was isolated from the Sambhar Salt Lake, Rajasthan India. This organism exhibited significance antibacterial and antifungal activity against Proteus vulgaris, Bacillus subtilis, Aspergillus niger, Rhizopus oligosporus and Penicillium chrysogenum respectively. The bioactive constituent responsible for it was extracted by three phase partitioning and purified by column chromatography. The purified compound was further characterized by FTIR-ATR, NMR and Mass spectrometry. The mass spectra show a molecular ion of m/z 301.14. The compound has very high antimicrobial activity showing 35mm zone of inhibition against Bacillus subtilis.
Subject(s)
Anti-Bacterial Agents , Antifungal Agents , Bacillus subtilis , Galanin/analogs & derivatives , India , Substance P/analogs & derivativesABSTRACT
A large body of evidence suggests that the neuropeptide galanin plays an important role in seizure control. In line with this, it was demonstrated that the galanin analogue, NAX-5055, exerts a potent anticonvulsant activity in animal seizure models. We recently found that the NAX-5055-mediated anticonvulsant action involves modulation of both excitatory and inhibitory neurotransmission. Since homeostasis of neurotransmitters and cerebral energy metabolism are intimately linked, it was investigated whether the effects of NAX-5055 on neurotransmission involve changes in energy metabolism and in particular glucose- and amino acid metabolism. With this aim, cultured neurons from mouse brain were incubated with [U-13 C]glucose in absence or presence of NAX-5055. Since effects of NAX-5055 on neurotransmission were detected during repetitive stimulation, we tested potential metabolic effects while mimicking repetitive bursts of neurotransmitter release as occurring in the intact brain. The metabolic pathways were mapped using gas-chromatography coupled to mass-spectrometry. We found that NAX-5055 does not modify glucose metabolism in glutamatergic and GABAergic neurons. Furthermore, the effect of NAX-5055 on astrocyte-neuron metabolic interactions was investigated by incubating co-cultures of astrocytes and either glutamatergic or GABAergic neurons with [U-13 C]glucose or the glial-selective substrate [1,2-13 C]acetate, with or without NAX-5055. In the presence of NAX-5055, no changes in the metabolic landscape were traced. The findings suggest that the anticonvulsant action of NAX-5055 and the accompanying changes in neurotransmission do not involve alterations in energy and amino acid metabolism. Hence, NAX-5055 appears to be an anti-seizure drug candidate displaying no unwanted side effects concerning brain energy and amino acid homeostasis. © 2017 Wiley Periodicals, Inc.
Subject(s)
Amino Acids/metabolism , Anticonvulsants/pharmacology , Brain/drug effects , Energy Metabolism/drug effects , Galanin/analogs & derivatives , Lipopeptides/pharmacology , Animals , Animals, Newborn , Astrocytes/drug effects , Astrocytes/metabolism , Brain/cytology , Brain/metabolism , Cells, Cultured , Coculture Techniques , Energy Metabolism/physiology , Female , Galanin/pharmacology , Male , Mice , Neurons/drug effects , Neurons/metabolism , Neuropeptides/pharmacologyABSTRACT
Galanin, a neuropeptide co-released from noradrenergic and serotonergic projection neurons to the dentate gyrus, has recently emerged as an important mediator for signaling neuronal activity to the subgranular neurogenic stem cell niche supporting adult hippocampal neurogenesis. Galanin and its receptors appear to play key roles in depression-like behavior, and effects on hippocampal neurogenesis are relevant to pharmacological strategies for treating depression, which in part appear to rely on restoring altered neurogenesis. We previously demonstrated that the GalR2/3 receptor agonist Gal 2-11 is proliferative and proneurogenic for postnatal hippocampal progenitor cells; however, the specific receptor mediation remained to be identified. With the recent availability of M1145 (a specific GalR2 agonist), and SNAP 37889 (GalR3 specific antagonist), we extend our previous studies and show that while M1145 has no proliferative effect, the co-treatment of postnatal rat hippocampal progenitors with Gal 2-11 and SNAP 37889 completely abolished the Gal 2-11 proliferative effects. Taken together, these results clearly demonstrate that GalR3 and not GalR2 is the specific receptor subtype that mediates the proliferative effects of galanin on hippocampal progenitor cells. These results implicate GALR3 in the mediation of galanin neurogenic effects and, potentially, its neurogenic anti-depressant effects.
Subject(s)
Cell Proliferation/drug effects , Galanin/analogs & derivatives , Hippocampus/drug effects , Indoles/pharmacology , Neural Stem Cells/drug effects , Peptide Fragments/pharmacology , Receptor, Galanin, Type 3/antagonists & inhibitors , Animals , Galanin/pharmacology , Neurogenesis/drug effects , Rats , Receptor, Galanin, Type 2/agonistsABSTRACT
The potential clinical utility of galanin peptidic analogs has been hindered by poor metabolic stability, lack of brain penetration, and hyperglycemia. In addition to possessing potent anticonvulsant efficacy, galanin analogs are analgesic in various assays. The purpose of these studies was to evaluate the lead galanin receptor type 2 (GalR2)-preferring analog, NAX 810-2, in various pain assays, as well as determine any potential for insulin inhibition, growth hormone stimulation, and cognitive impairment. NAX 810-2 was evaluated in mouse (carrageenan, formalin, tail flick, plantar incision) and rat pain models (partial sciatic nerve ligation). NAX 810-2 dose-dependently increased paw withdrawal latency following plantar administration of carrageenan (ED50 4.7 mg/kg). At a dose of 8 mg/kg, NAX 810-2 significantly attenuated nociceptive behaviors following plantar administration of formalin, and this was observed for both phase I (acute) and phase II (inflammatory) components of the formalin behavioral response. NAX-810-2 was active at higher doses in the mouse tail flick model (ED50 20.2 mg/kg) and similarly, reduced mechanical allodynia following plantar incision in mice at a dose of 24 mg/kg. NAX 810-2 also reduced mechanical allodynia in the partial sciatic nerve ligation model at a dose of 4 mg/kg. In addition, NAX 810-2 did not impair insulin secretion at doses of 2.5 and 8 mg/kg (acutely) or at a dose of 8 mg/kg given daily for 5 days. Similarly, 8 mg/kg (twice daily, 5 days) of NAX 810-2 did not increase growth hormone levels. These results demonstrate that NAX 810-2 possesses a favorable pre-clinical profile as a novel and first-in-class analgesic.
Subject(s)
Analgesics/metabolism , Analgesics/therapeutic use , Galanin/analogs & derivatives , Pain/drug therapy , Receptor, Galanin, Type 2/metabolism , Analgesics/pharmacology , Animals , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical/methods , Galanin/metabolism , Galanin/pharmacology , Galanin/therapeutic use , Male , Mice , Pain/pathology , Pain Measurement/drug effects , Pain Measurement/methods , Rats , Rats, Sprague-DawleyABSTRACT
OBJECTIVE: Potential clinical utility of galanin or peptidic analogs has been hindered by poor metabolic stability, lack of brain penetration, and hyperglycemia due to galanin receptor subtype 1 (GalR1) activation. NAX 810-2, a galanin receptor subtype 2 (GalR2)-preferring galanin analog, possesses 15-fold greater affinity for GalR2 over GalR1 and protects against seizures in the mouse 6 Hz, corneal kindling, and Frings audiogenic seizure models. The purpose of these studies was to further evaluate the preclinical efficacy and pharmacokinetics of NAX 810-2 in mice. METHODS: NAX 810-2 was administered by intravenous (i.v.; tail vein, bolus) injection to fully kindled (corneal kindling assay) or naive CF-1 mice (6 Hz assay and pharmacokinetic studies). Plasma NAX 810-2 levels were determined from trunk blood samples. NAX 810-2 was also added to human plasma at various concentrations for determination of plasma protein binding. RESULTS: In the mouse corneal kindling model, NAX 810-2 dose-dependently blocked seizures following intravenous administration (median effective dose [ED50 ], 0.5 mg/kg). In the mouse 6 Hz (32 mA) seizure model, it was demonstrated that NAX 810-2 dose-dependently blocked seizures following bolus administration (0.375-1.5 mg/kg, i.v.; ED50 , 0.7 mg/kg), with a time-to-peak effect of 0.5 h posttreatment. Motor impairment was observed at 1.5 mg/kg, i.v., whereas one-half of this dose, 0.75 mg/kg, i.v., was maximally effective in the 6 Hz test. Plasma levels of NAX 810-2 show linear pharmacokinetics following intravenous administration and a half-life of 1.2 h. Functional agonist activity studies demonstrate that NAX 810-2 effectively activates GalR2 at therapeutic concentrations. SIGNIFICANCE: These studies further suggest the potential utility of NAX 810-2 as a novel therapy for epilepsy.
Subject(s)
Anticonvulsants/administration & dosage , Anticonvulsants/pharmacokinetics , Drug Evaluation, Preclinical , Receptor, Galanin, Type 2/chemistry , Seizures/drug therapy , Animals , Anticonvulsants/pharmacology , Area Under Curve , Cornea/innervation , Disease Models, Animal , Dose-Response Relationship, Drug , Electric Stimulation/adverse effects , Galanin/analogs & derivatives , Galanin/pharmacokinetics , Galanin/therapeutic use , Injections, Intravenous , Kindling, Neurologic/drug effects , Male , Mice , Movement Disorders/drug therapy , Movement Disorders/etiology , Protein Binding/drug effects , Receptor, Galanin, Type 1/metabolism , Receptor, Galanin, Type 2/antagonists & inhibitors , Seizures/complications , Seizures/etiology , Time FactorsABSTRACT
Sixteen broad-spectrum cephalosporin-resistant Klebsiella pneumoniae isolates were recovered between April and June 2013 from Palestinian hospitals, Gaza Strip. Genes encoding extended-spectrum beta-lactamases (ESBLs) and other resistance genes were characterized by polymerase chain reaction and sequencing. The following ß-lactamase genes were detected: blaCTX-M-15+ blaSHV1+ blaTEM-1 (six isolates), blaCTX-M-15+ blaSHV5+ blaOXA-1 (two isolates), blaCTX-M-14a (two isolates), blaCTX-M-15+ blaSHV33 (one isolate), blaCTX-M-15+ blaTEM-1 (one isolate), blaCTX-M-15+ blaSHV12+ blaOXA-1(one isolate), blaCTX-M-15+ blaSHV5 (one isolate), blaCTX-M-15+ blaSHV1 (one isolate), and blaCTX-M-3 (one isolate). The ISEcp1 (in four cases truncated by IS26), orf477, or IS903 sequences were found upstream or downstream of blaCTX-M genes. The aac(6')-Ib-cr gene was found in seven isolates. The qnrS1 and qnrB1 genes were detected in five isolates and two isolates, respectively. Seven isolates contained class 1 integrons with four gene cassette arrangements: dfrA5 (three isolates), dfrA12-orf-aadA2 (two isolates), dfrA17-aadA5 (one isolate), and aadA1 (one isolate). A high clonal diversity was also observed among studied isolates by pulsed-field gel electrophoresis (12 unrelated profiles). This study demonstrates for the first time the emergence and polyclonal spread of multidrug-resistant ESBL-producing K. pneumoniae isolates among patients in a hospital setting in Gaza Strip, Palestine.