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Experimental Animals Nov 2023Epilepsy is the most common chronic disorder in the nervous system, mainly characterized by recurrent, periodic, unpredictable seizures. Post-translational modifications...
Epilepsy is the most common chronic disorder in the nervous system, mainly characterized by recurrent, periodic, unpredictable seizures. Post-translational modifications (PTMs) are important protein functional regulators that regulate various physiological and pathological processes. It is significant for cell activity, stability, protein folding, and localization. Phosphoglycerate kinase (PGK) 1 has traditionally been studied as an important adenosine triphosphate (ATP)-generating enzyme of the glycolytic pathway. PGK1 catalyzes the reversible transfer of a phosphoryl group from 1, 3-bisphosphoglycerate (1, 3-BPG) to ADP, producing 3-phosphoglycerate (3-PG) and ATP. In addition to cell metabolism regulation, PGK1 is involved in multiple biological activities, including angiogenesis, autophagy, and DNA repair. However, the exact role of PGK1 succinylation in epilepsy has not been thoroughly investigated. The expression of PGK1 succinylation was analyzed by Immunoprecipitation. Western blots were used to assess the expression of PGK1, angiostatin, and vascular endothelial growth factor (VEGF) in a rat model of lithium-pilocarpine-induced acute epilepsy. Behavioral experiments were performed in a rat model of lithium-pilocarpine-induced acute epilepsy. ELISA method was used to measure the level of S100β in serum brain biomarkers' integrity of the blood-brain barrier. The expression of the succinylation of PGK1 was decreased in a rat model of lithium-pilocarpine-induced acute epilepsy compared with the normal rats in the hippocampus. Interestingly, the lysine 15 (K15), and the arginine (R) variants of lentivirus increased the susceptibility in a rat model of lithium-pilocarpine-induced acute epilepsy, and the K15 the glutamate (E) variants, had the opposite effect. In addition, the succinylation of PGK1 at K15 affected the expression of PGK1 succinylation but not the expression of PGK1total protein. Furthermore, the study found that the succinylation of PGK1 at K15 may affect the level of angiostatin and VEGF in the hippocampus, which also affects the level of S100β in serum. In conclusion, the mutation of the K15 site of PGK1 may alter the expression of the succinylation of PGK1 and then affect the integrity of the blood-brain barrier through the angiostatin / VEGF pathway altering the activity of epilepsy, which may be one of the new mechanisms of treatment strategies.
Topics: Rats; Animals; Phosphoglycerate Kinase; Vascular Endothelial Growth Factor A; Blood-Brain Barrier; Lithium; Pilocarpine; Angiostatins; Seizures; Epilepsy; Adenosine Triphosphate
PubMed: 37258131
DOI: 10.1538/expanim.23-0019 -
The Journal of Neuroscience : the... Oct 2023A significant proportion of temporal lobe epilepsy (TLE) patients experience drug-resistant seizures associated with mesial temporal sclerosis, in which there is...
A significant proportion of temporal lobe epilepsy (TLE) patients experience drug-resistant seizures associated with mesial temporal sclerosis, in which there is extensive cell loss in the hippocampal CA1 and CA3 subfields, with a relative sparing of dentate gyrus granule cells and CA2 pyramidal neurons (PNs). A role for CA2 in seizure generation was suggested based on findings of a reduction in CA2 synaptic inhibition (Williamson and Spencer, 1994) and the presence of interictal-like spike activity in CA2 in resected hippocampal tissue from TLE patients (Wittner et al., 2009). We recently found that in the pilocarpine-induced status epilepticus (PILO-SE) mouse model of TLE there was an increase in CA2 intrinsic excitability associated with a loss of CA2 synaptic inhibition. Furthermore, chemogenetic silencing of CA2 significantly reduced seizure frequency, consistent with a role of CA2 in promoting seizure generation and/or propagation (Whitebirch et al., 2022). In the present study, we explored the cellular basis of this inhibitory deficit using immunohistochemical and electrophysiological approaches in PILO-SE male and female mice. We report a widespread decrease in the density of pro-cholecystokinin-immunopositive (CCK) interneurons and a functional impairment of CCK interneuron-mediated inhibition of CA2 PNs. We also found a disruption in the perisomatic perineuronal net in the CA2 stratum pyramidale. Such pathologic alterations may contribute to an enhanced excitation of CA2 PNs and CA2-dependent seizure activity in the PILO-SE mouse model. Impaired synaptic inhibition in hippocampal circuits has been identified as a key feature that contributes to the emergence and propagation of seizure activity in human patients and animal models of temporal lobe epilepsy (TLE). Among the hippocampal subfields, the CA2 region is particularly resilient to seizure-associated neurodegeneration and has been suggested to play a key role in seizure activity in TLE. Here we report that perisomatic inhibition of CA2 pyramidal neurons mediated by cholecystokinin-expressing interneurons is selectively reduced in acute hippocampal slices from epileptic mice. Parvalbumin-expressing interneurons, in contrast, appear relatively conserved in epileptic mice. These findings advance our understanding of the cellular mechanisms underlying inhibitory disruption in hippocampal circuits in a mouse model of spontaneous recurring seizures.
Topics: Humans; Male; Female; Mice; Animals; CA2 Region, Hippocampal; Epilepsy, Temporal Lobe; Cholecystokinin; Hippocampus; Interneurons; Seizures; Pilocarpine; Status Epilepticus; Disease Models, Animal
PubMed: 37643861
DOI: 10.1523/JNEUROSCI.2091-22.2023 -
Scientific Reports Oct 2023Overactive bladder (OAB) is a common, long-term symptom complex with a high prevalence in women worldwide. OAB has caused a social burden, and effective treatments are...
Overactive bladder (OAB) is a common, long-term symptom complex with a high prevalence in women worldwide. OAB has caused a social burden, and effective treatments are urgently needed. However, the pathogenesis of OAB has yet to be elucidated. Model rats underwent bladder outlet obstruction surgery. In the 2nd, 3rd, and 4th weeks after surgery, metabolic cages were used to detect the 12 h urine volume of rats in the sham and model groups. The urodynamic parameters bladder leak point pressure (BPLL), maximum voiding pressure (MVP), residual volume (RV), maximum bladder capacity (MBC), bladder compliance (BC), voided efficiency (VE), and non-voiding contractions (NVCs) were also detected. Moreover, the contractile responses of isolated detrusor muscles to electrical and carbachol stimulation were examined at the abovementioned time points. At the 4th week after surgery, the bladders of both groups were obtained for hematoxylin-eosin (H&E) and Masson's trichrome staining. Real-time qPCR and Western blot were performed to quantify the expression of choline acetyltransferase (ChAT) and solute carrier family 17 member 9 (SLC17A9). At week 4, compared with the sham group, the 12 h urine volume of PBOO group increased significantly. The BLPP, MVP, VE, MBC, and NVCs increased significantly, and the VE was significantly reduced in 4-week PBOO group. The contractile responses of isolated detrusor muscles to electrical and carbachol stimulation significantly increased in 4-week PBOO group. In the 4-week PBOO group, the bladder wall and the ratio of bladder muscle to collagen within the bladder smooth muscle layer wall were significantly higher than those in the sham group. ChAT and SLC17A9 mRNA and protein expression in the OAB model rats significantly increased. At 4 weeks after PBOO, the OAB model was successfully established. The gene and protein expression levels of ChAT and SLC17A9 increased in the bladder of the OAB model, suggesting that OAB may be related to increased excitatory purinergic and cholinergic expression.
Topics: Humans; Rats; Female; Animals; Urinary Bladder, Overactive; Urinary Bladder Neck Obstruction; Carbachol; Urinary Bladder; Cholinergic Agents
PubMed: 37884550
DOI: 10.1038/s41598-023-45014-5 -
Pharmaceutics Feb 2024Glaucoma encompasses a group of optic neuropathies characterized by complex and often elusive etiopathology, involvihttng neurodegeneration of the optic nerve in... (Review)
Review
Glaucoma encompasses a group of optic neuropathies characterized by complex and often elusive etiopathology, involvihttng neurodegeneration of the optic nerve in conjunction with abnormal intraocular pressure (IOP). Currently, there is no cure for glaucoma, and treatment strategies primarily aim to halt disease progression by managing IOP. This review delves into the etiopathology, diagnostic methods, and treatment approaches for glaucoma, with a special focus on IOP management. We discuss a range of active pharmaceutical ingredients used in glaucoma therapy, emphasizing their chemical structure, pharmacological action, therapeutic effectiveness, and safety/tolerability profiles. Notably, most of these therapeutic agents are administered as topical formulations, a critical aspect considering patient compliance and drug delivery efficiency. The classes of glaucoma therapeutics covered in this review include prostaglandin analogs, beta blockers, alpha agonists, carbonic anhydrase inhibitors, Rho kinase inhibitors, and miotic (cholinergic) agents. This comprehensive overview highlights the importance of topical administration in glaucoma treatment, offering insights into the current state and future directions of pharmacological management in glaucoma.
PubMed: 38399328
DOI: 10.3390/pharmaceutics16020274 -
American Journal of Ophthalmology Sep 2023To evaluate the safety, efficacy, and pharmacokinetics of pilocarpine hydrochloride 1.25% (Pilo hereafter) compared with vehicle when administered bilaterally, twice... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
To evaluate the safety, efficacy, and pharmacokinetics of pilocarpine hydrochloride 1.25% (Pilo hereafter) compared with vehicle when administered bilaterally, twice daily (6 hours apart) for 14 days in participants with presbyopia.
DESIGN
Phase 3, randomized (1:1), controlled, double-masked, multicenter study.
METHODS
Participants (40-55 years of age) had objective and subjective evidence of presbyopia affecting daily activities with mesopic, high-contrast, binocular distance-corrected near visual acuity (DCNVA) of 20/40 to 20/100. The primary/key secondary endpoint was the proportion of participants gaining ≥3 lines in mesopic/photopic, high-contrast, binocular DCNVA on day 14 (last study visit), hour 9 (3 hours after the second dose), with no more than a 5-letter loss in mesopic/photopic corrected distance visual acuity with the same refractive correction. Key safety measures included treatment-emergent adverse events (TEAEs) and some ocular measurements. Pilocarpine plasma levels were assessed in approximately 10% of enrolled participants.
RESULTS
Overall, 230 participants were randomized to Pilo twice daily (N = 114) and vehicle (N = 116). The proportion of participants achieving the primary and key secondary efficacy endpoints was statistically significantly greater with Pilo twice daily than vehicle, with between-treatment differences of 27.3% (95% CI = 17.3, 37.4) and 26.4% (95% CI = 16.8, 36.0), respectively. The most common TEAE was headache, reported in 10 participants (8.8%, Pilo group) and 4 participants (3.4%, vehicle group). Pilocarpine's accumulation index on day 14 was ≤1.11 after the second dose.
CONCLUSIONS
Near-vision improvements were statistically greater with Pilo twice daily than with vehicle, without compromising distance acuity. The safety profile of Pilo twice daily was consistent with that of Pilo once daily, and systemic accumulation was minimal, supporting twice daily administration.
Topics: Humans; Pilocarpine; Presbyopia; Visual Acuity; Refraction, Ocular; Double-Blind Method
PubMed: 37149245
DOI: 10.1016/j.ajo.2023.05.008 -
European Journal of Pharmacology Dec 2023Neuroinflammation mediated by microglia made a significant contribution in the pathophysiology of epilepsy. Icariin (ICA), a bioactive ingredient isolated from...
Neuroinflammation mediated by microglia made a significant contribution in the pathophysiology of epilepsy. Icariin (ICA), a bioactive ingredient isolated from Epimedium, has been shown to present both antioxidant and anti-inflammatory properties. This study was to explore the potential therapeutic effects of icariin on mouse pilocarpine model of epilepsy and its underlying mechanisms in vivo and in vitro. To this end, we firstly measured the serum concentrations of the proinflammatory cytokines IL-1β and IL-6 from patients with temporal lobe epilepsy and found that patients with a higher seizure frequency showed correspondingly higher inflammatory reaction. Mouse pharmacokinetic study, transmembrane transportation assay, and cell viability assay collectively demonstrated that ICA was able to cross the blood-brain barrier and has good biocompatibility. The acute and chronic epilepsy models were next established in a pilocarpine mouse model of acquired epilepsy. Icariin has been identified that it could cross the blood-brain barrier and enter the hippocampus to exhibit therapeutic effects. ICA treatment dramatically promoted microglial polarization to the M2 phenotype in epilepsy mice both in the acute and chronic phases. Reduced release of M1-associated proinflammatory factors, such as IL-1β and IL-6, corroborates the altered glial cell polarization. Furthermore, ICA alleviated seizure intensity and mortality in acute phase epileptic mice. Models in the chronic group also showed improved general condition, cognition ability, and memory function after ICA treatment. Taken together, our research strongly suggested that icariin has the potential to treat epilepsy via inhibiting neuroinflammation by promoting microglial polarization to the M2 phenotype.
Topics: Humans; Mice; Animals; Pilocarpine; Interleukin-6; Neuroinflammatory Diseases; Epilepsy; Seizures; Anti-Inflammatory Agents; Microglia; Disease Models, Animal
PubMed: 37866741
DOI: 10.1016/j.ejphar.2023.176141 -
Naunyn-Schmiedeberg's Archives of... Sep 2023We investigated the role of RhoA/Rho-kinase (ROCK) and PKC in the inhibitory effect of L-cysteine/hydrogen sulfide (HS) pathway on the carbachol-mediated contraction of...
We investigated the role of RhoA/Rho-kinase (ROCK) and PKC in the inhibitory effect of L-cysteine/hydrogen sulfide (HS) pathway on the carbachol-mediated contraction of mouse bladder smooth muscle. Carbachol (10-10 M) induced a concentration-dependent contraction in bladder tissues. L-cysteine (HS precursor; 10 M) and exogenous HS (NaHS; 10 M) reduced the contractions evoked by carbachol by ~ 49 and ~ 53%, respectively, relative to control. The inhibitory effect of L-cysteine on contractions to carbachol was reversed by 10 M PAG (~ 40%) and 10 M AOAA (~ 55%), cystathionine-gamma-lyase (CSE) and cystathionine-β-synthase (CBS) inhibitor, respectively. Y-27632 (10 M) and GF 109203X (10 M), a specific ROCK and PKC inhibitor, respectively, reduced contractions evoked by carbachol (~ 18 and ~ 24% respectively), and the inhibitory effect of Y-27632 and GF 109203X on contractions was reversed by PAG (~ 29 and ~ 19%, respectively) but not by AOAA. Also, Y-27632 and GF 109203X reduced the inhibitory responses of L-cysteine on the carbachol-induced contractions (~ 38 and ~ 52% respectively), and PAG abolished the inhibitory effect of L-cysteine on the contractions in the presence of Y-27632 (~ 38%). Also, the protein expressions of CSE, CBS, and 3-MST enzymes responsible for endogenous HS synthesis were detected by Western blot method. HS level was increased by L-cysteine, Y-27632, and GF 109203X (from 0.12 ± 0.02 to 0.47 ± 0.13, 0.26 ± 0.03, and 0.23 ± 0.06 nmol/mg respectively), and this augmentation in HS level decreased with PAG (0.17 ± 0.02, 0.15 ± 0.03, and 0.07 ± 0.04 nmol/mg respectively). Furthermore, L-cysteine and NaHS reduced carbachol-induced ROCK-1, pMYPT1, and pMLC20 levels. Inhibitory effects of L-cysteine on ROCK-1, pMYPT1, and pMLC20 levels, but not of NaHS, were reversed by PAG. These results suggest that there is an interaction between L-cysteine/HS and RhoA/ROCK pathway via inhibition of ROCK-1, pMYPT1, and pMLC20, and the inhibition of RhoA/ROCK and/or PKC signal pathway may be mediated by the CSE-generated HS in mouse bladder.
Topics: Mice; Animals; Urinary Bladder; rho-Associated Kinases; Cysteine; Carbachol; Cystathionine; Hydrogen Sulfide; Cystathionine gamma-Lyase; Cystathionine beta-Synthase; Muscle, Smooth; Muscle Contraction
PubMed: 36894621
DOI: 10.1007/s00210-023-02440-6 -
Behavioural Brain Research Aug 2023Status epilepticus is a neurological disorder that can result in various neuropathological conditions and presentations. Various studies involving animal models have... (Review)
Review
Status epilepticus is a neurological disorder that can result in various neuropathological conditions and presentations. Various studies involving animal models have been accomplished to understand and replicating its prominent manifestations including characteristics of related clinical cases. Up to these days, there are variety of methods and techniques to be utilized in inducing this disorder that can be chemically or electrically applied which depending on the experimental designs and targets of the studies. In particular, the chemically induced pilocarpine animal model of status epilepticus is a reliable choice which has evolved for 40 years from its initial discovery back in 1983. Although the development of the model can be considered as a remarkable breakthrough in understanding status epilepticus, several aspects of the model have been improved, throughout the years. Among the major issues in developing this model are the morbidity and mortality rates during induction process. Several modifications have been introduced in the process by different studies to tackle the related problems including application of dose fractionation, adaptation of pilocarpine to lithium-pilocarpine model and utilization of various drugs. Despite all challenges and drawbacks, this model has proven its pertinent and relevance with improvements that have been adapted since it was introduced 40 years ago. In this review, we emphasize on the evolution of this animal model from the beginning until now (1983 - 2023) and the related issues that have made this model still a popular choice in status epilepticus studies.
Topics: Animals; Pilocarpine; Electroencephalography; Status Epilepticus; Models, Animal; Disease Models, Animal
PubMed: 37348654
DOI: 10.1016/j.bbr.2023.114551 -
Respiratory Research Jul 2023Accumulating clinical evidence links Obstructive Sleep Apnea (OSA) with worse outcomes of asthma, but impact on airway function remains sparsely studied. We tested...
INTRODUCTION
Accumulating clinical evidence links Obstructive Sleep Apnea (OSA) with worse outcomes of asthma, but impact on airway function remains sparsely studied. We tested effects of Chronic Intermittent Hypoxia (CIH) - a hallmark of OSA - on airway hyperresponsiveness (AHR), in a rat model of chronic allergen-induced inflammation.
METHODS
Brown Norway rats were exposed to six weeks of CIH or normoxia (NORM) concurrent with weekly house dust mites (HDM) or saline (SAL) challenges. At endpoint, we assessed responses to seven Methacholine (Mch) doses (0, 4, 8, 16, 32, 64, 128 mg/mL) on a FlexiVent system (Scireq). Maximal (or plateau) responses (reactivity) for total respiratory system Resistance (R) and Elastance (E), Newtonian airway resistance (R a measure of central airways function) and tissue damping (G, a measure of distal airways function) were plotted.
RESULTS
HDM/CIH-treated animals demonstrated the highest reactivity to Mch in R and E compared to all other groups (HDM/NORM, SAL/CIH and SAL/NORM p < 0.05 for all comparisons, for doses 5-7 for R, and for doses 4-7 for E). The enhanced R response was due to an increase in G (doses 4-7, p < 0.05 for comparisons to all other groups), whereas R was not affected by CIH.
CONCLUSIONS
In rats chronically challenged with HDM, concurrent CIH exposure induces AHR primarily in the distal airways, which affects the respiratory system frequency-dependent elastic properties.
Topics: Rats; Animals; Pyroglyphidae; Allergens; Respiratory Hypersensitivity; Lung; Hypoxia; Methacholine Chloride; Inflammation; Sleep Apnea, Obstructive; Disease Models, Animal
PubMed: 37468919
DOI: 10.1186/s12931-023-02493-4 -
The Journal of Emergency Medicine Oct 2023Anticholinergic toxicity is a common cause of delirium in emergency department patients. The standard antidotal treatment for anticholinergic toxicity is physostigmine....
BACKGROUND
Anticholinergic toxicity is a common cause of delirium in emergency department patients. The standard antidotal treatment for anticholinergic toxicity is physostigmine. Physostigmine functions as a reversible acetylcholinesterase inhibitor that readily crosses the blood-brain barrier. Rivastigmine is another member of this class currently approved for the treatment of Alzheimer's disease and Parkinson's disease. Rivastigmine also crosses the blood-brain barrier and has been found to be effective in the management of anticholinergic toxicity in limited case reports.
CASE REPORT
A 61-year-old women presented to the emergency department via emergency medical services with altered mental status and a Glasgow Coma Scale score of 8 out of 15. She was found down near multiple medication bottles, including diphenhydramine and dicyclomine. Her physical examination was consistent with anticholinergic toxicity with mydriasis, obtundation, and warm flushed skin. In addition to standard resuscitation, she received two doses of rivastigmine 3 mg via nasogastric tube. After the second dose she was alert and oriented. She was admitted to the intensive care unit and had a rivastigmine patch applied. She was deemed back to her baseline 27 h after presentation. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although the standard antidotal treatment for anticholinergic toxicity is physostigmine, there is a national shortage of this medication. In the absence of this standard antidote, it is reasonable for emergency physicians to use rivastigmine as an alternative treatment. This can be delivered orally or via nasogastric tube with dosing each hour until resolution of symptoms. Alternatively, in consultation with toxicology, it may be reasonable to use transdermal rivastigmine, as it provides consistent drug absorption for 24 h.
Topics: Humans; Female; Middle Aged; Rivastigmine; Physostigmine; Cholinergic Antagonists; Acetylcholinesterase; Cholinesterase Inhibitors; Antidotes; Anticholinergic Syndrome; Delirium; Transdermal Patch
PubMed: 37716903
DOI: 10.1016/j.jemermed.2023.06.008