Choline Acetyltransferase Levels Research Articles

Restoration of injured motoneurons reduces microglial proliferation in the adult rat facial nucleus.

In the axotomized facial nucleus (axotFN), the levels of choline acetyltransferase, vesicular acetylcholine transporter, and gamma amino butyric acid A receptor α1 are decreased, after which the microglia begin to proliferate around injured motoneuron cell bodies. We conjectured that an injury signal released from the injured motoneurons triggers the microglial proliferation in the axotFN. However, it is unclear whether the level of microglial proliferation is dependent on the degree of motoneuronal insult. In this study, we investigated the relationship between the extents of motoneuronal injury and microglial proliferation in a rat axotFN model. Administration of glial cell line-derived neurotrophic factor, N-acetyl L-cysteine, or salubrinal at the transection site ameliorated the increase in c-Jun and the reductions in levels of phosphorylated cAMP response element binding protein (p-CREB) and functional molecules in the injured motoneurons. Concurrently, the levels of the microglial marker ionized calcium-binding adapter molecule 1 and of macrophage colony-stimulating factor (cFms), proliferating cell nuclear antigen, and p-p38/p38 were significantly downregulated in microglia. These results demonstrate that the recovery of motoneuron function resulted in the reduction in microglial proliferation. We conclude that the degree of neuronal injury regulates the levels of microglial proliferation in the axotFN.

Neuroprotective effect of whey protein hydrolysate containing leucine-aspartate-isoleucine-glutamine-lysine on HT22 cells in hydrogen peroxide–induced oxidative stress

This study aimed to investigate the neuroprotective effects of whey protein hydrolysate (WPH) containing the pentapeptide leucine-aspartate-isoleucine-glutamine-lysine (LDIQK). Whey protein hydrolysate (50, 100, and 200 µg/mL) demonstrated the ability to restore the viability of HT22 cells subjected to 300 µM hydrogen peroxide (H2O2)-induced oxidative stress. Furthermore, at a concentration of 200 µg/mL, it significantly reduced the increase in reactive oxygen species production and calcium ion (Ca2+) influx induced by H2O2 by 46.1% and 46.2%, respectively. Similarly, the hydrolysate significantly decreased the levels of p-tau, a hallmark of tauopathy, and BCL2 associated X (BAX), a proapoptosis factor, while increasing the protein levels of choline acetyltransferase (ChAT), an enzyme involved in acetylcholine synthesis, brain-derived neurotrophic factor (BDNF), a nerve growth factor, and B-cell lymphoma 2 (BCL2, an antiapoptotic factor. Furthermore, it increased nuclear factor erythroid 2-related factor 2 (Nrf2)-hemoxygenase-1(HO-1) signaling, which is associated with the antioxidant response, while reducing the activation of mitogen-activated protein kinase (MAPK) signaling pathway components, namely phosphor-extracellular signal-regulated kinases (p-ERK), phosphor-c-Jun N-terminal kinases (p-JNK), and p-p38. Column chromatography and tandem mass spectrometry analysis identified LDIQK as a compound with neuroprotective effects in WPH; it inhibited Ca2+ influx and regulated the BAX/BCL2 ratio. Collectively, WPH containing LDIQK demonstrated neuroprotective effects against H2O2-induced neuronal cell damage, suggesting that WPH or its active peptide, LDIQK, may serve as a potential edible agent for improving cognitive dysfunction.

Excitatory purinergic and cholinergic expression changed in a partial bladder outlet obstruction-induced overactive bladder rat model

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.

Chronic stress induces pulmonary epithelial cells to produce acetylcholine that remodels lung pre-metastatic niche of breast cancer by enhancing NETosis

BackgroundChronic stress promotes most hallmarks of cancer through impacting the malignant tissues, their microenvironment, immunity, lymphatic flow, etc. Existing studies mainly focused on the roles of stress-induced activation of systemic sympathetic nervous system and other stress-induced hormones, the organ specificity of chronic stress in shaping the pre-metastatic niche remains largely unknown. This study investigated the role of chronic stress in remodeling lung pre-metastatic niche of breast cancer.MethodsBreast cancer mouse models with chronic stress were constructed by restraint or unpredictable stress. Expressions of tyrosine hydroxylase, vesicular acetylcholine transporter (VAChT), EpCAM and NETosis were examined by immunofluorescence and confocal microscopy. mRNA and protein levels of choline acetyltransferase (ChAT), VAChT, and peptidylarginine deiminase 4 were detected by qRT-PCR and Western blotting, respectively. Immune cell subsets were analyzed by flow cytometry. Acetylcholine (ACh) and chemokines were detected by ELISA and multi chemokine array, respectively. ChAT in lung tissues from patients was examined by immunohistochemistry.ResultsBreast cancer-bearing mice suffered chronic stress metastasized earlier and showed more severe lung metastasis than did mice in control group. VAChT, ChAT and ChAT+ epithelial cells were increased significantly in lung of model mice undergone chronic stress. ACh and chemokines especially CXCL2 in lung culture supernatants from model mice with chronic stress were profoundly increased. Chronic stress remodeled lung immune cell subsets with striking increase of neutrophils, enhanced NETosis in lung and promoted NETotic neutrophils to capture cancer cells. ACh treatment resulted in enhanced NETosis of neutrophils. The expression of ChAT in lung tissues from breast cancer patients with lung metastasis was significantly higher than that in patients with non-tumor pulmonary diseases.ConclusionsChronic stress promotes production of CXCL2 that recruits neutrophils into lung, and induces pulmonary epithelial cells to produce ACh that enhances NETosis of neutrophils. Our findings demonstrate for the first time that chronic stress induced epithelial cell derived ACh plays a key role in remodeling lung pre-metastatic niche of breast cancer.

Codium fragile Suppresses PM2.5-Induced Cognitive Dysfunction by Regulating Gut-Brain Axis via TLR-4/MyD88 Pathway.

This study was conducted to evaluate the cognitive dysfunction improvement effect of aqueous extract of Codium fragile (AECF) by regulating the imbalance of the gut-brain axis in chronic particulate matter (PM)2.5-exposed mice. The physiological compounds of AECF were identified as hexadecanamide, oleamide, octadecanamide, stearidonic acid, and linolenic acid by the ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC Q-TOF MSE) analysis. To evaluate the effect of PM2.5 on the antioxidant system, superoxide dismutase (SOD) contents, reduced glutathione (GSH) contents, and malondialdehyde (MDA) contents were measured in colon and brain tissues. AECF significantly ameliorated the imbalance of the antioxidant systems. Also, AECF improved intestinal myeloperoxidase (MPO) activity, the abundance of the gut microbiome, short-chain fatty acids (SCFAs) contents, and tight junction protein expression against PM2.5-induced damage. In addition, AECF prevented PM2.5-induced inflammatory and apoptotic expression via the toll-like receptor-4 (TLR-4)/myeloid differentiation primary response 88 (MyD88) pathway in colon and brain tissues. Additionally, AECF enhanced the mitochondrial function, including the mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) contents in brain tissues. Furthermore, AECF regulated the cholinergic system, such as acetylcholine (ACh) contents, acetylcholinesterase (AChE) activity, and protein expression levels of AChE and choline acetyltransferase (ChAT) in brain tissues. To evaluate the effect of cognitive dysfunction caused by PM2.5-induced intestinal dysfunction, behavior tests such as Y-maze, passive avoidance, and Morris water maze tests were performed. From the results of the behavior tests, AECF ameliorated spatial learning and memory, short-term memory, and long-term learning and memory function. This study confirmed that AECF reduced PM2.5-induced cognitive dysfunction by regulating gut microbiome and inflammation, apoptosis, and mitochondrial function by enhancing the gut-brain axis. Based on these results, this study suggests that AECF, which contains fatty acid amides, might be a potential material for ameliorating PM2.5-induced cognitive dysfunction via gut-brain axis improvement.

MP-453088-5 THE EFFECT OF LOW–LEVEL TRANSCUTANEOUS VAGUS NERVE STIMULATION ON AUTONOMIC REMODELING OF GANGLIONATED PLEXI (GP) IN HUMANS

The intrinsic cardiac autonomic nervous system (CANS), which is formed by interconnected clusters of autonomic ganglia called ganglionated plexi (GP), has been found to play a key role in the onset and maintenance of atrial fibrillation (AF). The ability of GP neurons to change parasympathetic activity suggests that synaptic plasticity occurs at synapses generated on and by GP neurons. Such changes could be a source of maladaptive plasticity and fine-tuning autonomic innervation of the heart during AF Low-level tragus stimulation (LLTS), which has antiarrhythmic and anti-inflammatory properties, has been shown to benefit patients with paroxysmal AF. The purpose of this study was to determine the effect of LLTS on the synaptic plasticity of GP in patients undergoing open heart surgery by examining changes in protein levels of neural markers. Furthermore, the effect of LLTS on inflammatory markers in GP has been determined. Patients undergoing cardiac surgery (including patients with paroxysmal AF, persistent AF, or no history of AF) were randomized to active LLTS (20Hz, 30mA) for 1 hour or no stimulation. A 2-3 mm biopsy of the GP tissue was taken immediately after stimulation, and immunohistochemistry was used to stain for neural (choline acetyltransferase (ChAT), synaptophysin, S100B, PGP9.5, nNOS, and GFAP) and inflammatory markers (CD3, CD68). Twenty five patients were included. Patients' clinical and echocardiographic characteristics were distributed evenly across groups (LLTS, n=12, 75% male, age 65±9 years vs. sham, n=13, 92% male, age 63±11 years). In comparison to sham, LLTS significantly decreased the protein expression level of S100B, nNOS, GFAP, PGP9.5, and choline acetyltransferase (ChAT) in GP tissue (Figure 1). The expression of synaptophysin in both groups was not significantly different. Following stimulation, the expression of the inflammatory marker CD3 was significantly reduced. There was no statistically significant difference in CD68 expression between the LLTS and sham groups. Significant changes in neural markers within the GP occurred following LLTS, consistent with acute autonomic remodeling. Further studies are warranted to understand the clinical significance of this finding.

Lianmei Qiwu Decoction relieves diabetic cardiac autonomic neuropathy by regulating AMPK/TrkA/TRPM7 signaling pathway

This study investigated the effect of Lianmei Qiwu Decoction(LMQWD) on the improvement of cardiac autonomic nerve remodeling in the diabetic rat model induced by the high-fat diet and explored the underlying mechanism of LMQWD through the AMP-activated protein kinase(AMPK)/tropomyosin receptor kinase A(TrkA)/transient receptor potential melastatin 7(TRPM7) signaling pathway. The diabetic rats were randomly divided into a model group, an LMQWD group, an AMPK agonist group, an unloaded TRPM7 adenovirus group(TRPM7-N), an overexpressed TRPM7 adenovirus group(TRPM7), an LMQWD + unloaded TRPM7 adenovirus group(LMQWD+TRPM7-N), an LMQWD + overexpressed TRPM7 adenovirus group(LMQWD+TRPM7), and a TRPM7 channel inhibitor group(TRPM7 inhibitor). After four weeks of treatment, programmed electrical stimulation(PES) was employed to detect the arrhythmia susceptibility of rats. The myocardial cell structure and myocardial tissue fibrosis of myocardial and ganglion samples in diabetic rats were observed by hematoxylin-eosin(HE) staining and Masson staining. The immunohistochemistry, immunofluorescence, real-time quantitative polymerase chain reaction(RT-PCR), and Western blot were adopted to detect the distribution and expression of TRPM7, tyrosine hydroxylase(TH), choline acetyltransferase(ChAT), growth associated protein-43(GAP-43), nerve growth factor(NGF), p-AMPK/AMPK, and other genes and related neural markers. The results showed that LMQWD could significantly reduce the arrhythmia susceptibility and the degree of fibrosis in myocardial tissues, decrease the levels of TH, ChAT, and GAP-43 in the myocardium and ganglion, increase NGF, inhibit the expression of TRPM7, and up-regulate p-AMPK/AMPK and p-TrkA/TrkA levels. This study indicated that LMQWD could attenuate cardiac autonomic nerve remodeling in the diabetic state, and its mechanism was associated with the activation of AMPK, further phosphorylation of TrkA, and inhibition of TRPM7 expression.

Disturbed circadian rhythm and retinal degeneration in a mouse model of Alzheimer’s disease

The circadian clock is synchronized to the 24 h day by environmental light which is transmitted from the retina to the suprachiasmatic nucleus (SCN) primarily via the retinohypothalamic tract (RHT). Circadian rhythm abnormalities have been reported in neurodegenerative disorders such as Alzheimer's disease (AD). Whether these AD-related changes are a result of the altered clock gene expression, retina degeneration, including the dysfunction in RHT transmission, loss of retinal ganglion cells and its electrophysiological capabilities, or a combination of all of these pathological mechanisms, is not known. Here, we evaluated transgenic APP/PS1 mouse model of AD and wild-type mice at 6- and 12-month-old, as early and late pathological stage, respectively. We noticed the alteration of circadian clock gene expression not only in the hypothalamus but also in two extra-hypothalamic brain regions, cerebral cortex and hippocampus, in APP/PS1 mice. These alterations were observed in 6-month-old transgenic mice and were exacerbated at 12 months of age. This could be explained by the reduced RHT projections in the SCN of APP/PS1 mice, correlating with downregulation of hypothalamic GABAergic response in APP/PS1 mice in advanced stage of pathology. Importantly, we also report retinal degeneration in APP/PS1 mice, including Aβ deposits and reduced choline acetyltransferase levels, loss of melanopsin retinal ganglion cells and functional integrity mainly of inner retina layers. Our findings support the theory that retinal degeneration constitutes an early pathological event that directly affects the control of circadian rhythm in AD.

Plasminogen decreases Aβ42 and Tau deposition, and shows multi-beneficial effects on Alzheimer's disease in mice and humans

Alzheimer's disease (AD) is the most common neurodegenerative disorder in the world. The aggregation of both amyloid beta (Aβ) peptides extracellularly and Tau proteins intracellularly plays key roles in the pathological consequences of AD, which lead to cholinergic neurodegeneration and eventually death. Currently, there are no effective methods to stop the progression of AD. Using ex vivo, in vivo and clinical approaches, we investigated the functional effects of plasminogen on the widely used FAD, Aβ42 oligomer or Tau intracranial injection-induced AD mouse model and explored its therapeutic effects on patients with AD. The results show that intravenously injected plasminogen rapidly crosses the blood‒brain barrier (BBB); increases plasmin activity in the brain; colocalizes with and effectively promotes the clearance of Aβ42 peptide and Tau protein deposits ex vivo and in vivo; increases the choline acetyltransferase (ChAT) level and decreases the acetylcholinesterase (AChE) activity; and improves the memory functions. Clinically, when GMP-level plasminogen was administered to 6 AD patients for 1–2 weeks, their average scores on the Minimum Mental State Examination (MMSE), which is a standard scoring system used to measure the memory loss and cognitive deficits, were extremely significantly improved by 4.2 ± 2.23 points, e.g., an average increase from 15.5 ± 8.22 before treatment to 19.7 ± 7.09 after treatment. The preclinical study and pilot clinical study suggest that plasminogen is effective in treating AD and may be a promising drug candidate.

Effect of electroacupuncture at "Zusanli" (ST36) and "Tianshu" (ST25) on intestinal function and autonomic nerve balance in rats with irritable bowel syndrome

To study whether electroacupuncture (EA) of "Zusanli" (ST36) combined with "Tianshu" (ST25) has a synergistic effect in regulating the colonic function and autonomic nerve balance in rats with irritable bowel syndrome (IBS). Male Wistar rats were randomly divided into control, model, EA-ST36, and EA-ST36+ST25 groups, with 14 rats in each group. The IBS model was established by using water avoidance stress method. The visceral hypersensitivity was measured using the abdominal wall retraction reflex (AWR). The rectus abdominis electromyogram (EMG), intestinal electrical activity, and electrocardiogram (ECG) were recorded using a PowerLab data acquisition and analysis system. The contents of serum cAMP and cGMP were determined by ELISA, the expression levels of colonic tyrosine hydroxylase (TH) and choline acetyl-transferase (ChAT) proteins were determined by immunofluorescence staining and Western blot, respectively. Compared with the control group, the model group had an evident increase in the levels of AWR, LF, LF/HF, ChAT protein expression, cAMP and cGMP contents and cAMP/cGMP ratio (P<0.001, P<0.05), and a marked decrease in the levels of HF, frequency of slow waves of intestinal EMG, visceral pain threshold (PT), immunoactivity and expression of TH protein (P<0.05, P<0.001). In contrast to the model group, the levels of AWR, LF, LF/HF, ChAT protein expression and immunoactivity, cAMP and cGMP contents and ratio of cAMP/cGMP were significantly reduced (P<0.001, P<0.05, P<0.01), whereas the levels of frequency of slow waves of intestinal EMG, PT, and the immunoactivity and expression of TH were considerably increased (P<0.001, P<0.05) in both EA-ST36 and EA-ST36+ST25 groups. EA of both ST36 and ST36+ST25 can relieve visceral pain, and reduce sympathetic activity to improve autonomic nerve balance, but without apparent synergistic effect between EA-ST36 and EA-ST25 in rats with IBS.

Neuroprotective Effect of Barbaloin on Streptozotocin-Induced Cognitive Dysfunction in Rats via Inhibiting Cholinergic and Neuroinflammatory Cytokines Pathway-TNF-α/IL-1β/IL-6/NF-κB.

Streptozotocin (STZ) impairs memory in rats through altering the central nervous systems (CNS) as a result of impaired cholinergic dysfunction, oxidative stress, persistent hyperglycemia, and alterations in the glucagon-like peptide (GLP). In this model cholinergic agonist, antioxidant and antihyperglycemic treatment has been shown to have positive effects. Barbaloin has a variety of pharmacological effects. However, there is no evidence on how barbaloin improves memory dysfunction caused by STZ. Thus, we examined its effectiveness against cognitive damage caused by STZ at a dose of 60 mg/kg i.p. in Wistar rats. Blood glucose levels (BGL) and body weight (BW) were assessed. To assess learning and memory skills, the Y-maze test and Morris water maze (MWM) test were utilized. Superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), and glutathione (GSH) as oxidative stress markers were regulated to reverse the cognitive deterioration, and choline-acetyltransferase (ChAT) and acetyl-cholinesterase (AChE) as indicators of cholinergic dysfunction, nuclear factor kappa-B (NF-κB), IL-1β (interleukin-1β), IL-6, and tumor necrosis factor-α (TNF-α) contents were used. Barbaloin treatment thereby significantly decreased the BW and learning and memory capacities, resulting in substantial behavioral improvement in the Y-maze and MWM test. BGL, SOD, CAT, MDA, GSH, AChE, ChAT, NF-κB, IL-6, TNF-α, and IL-1β levels were also altered. In conclusion, the findings revealed that barbaloin had a protective impact against cognitive dysfunction caused by STZ.

Mountain-cultivated ginseng protects against cognitive impairments in aged GPx-1 knockout mice via activation of Nrf2/ChAT/ERK signaling pathway

BackgroundEscalating evidence shows that ginseng possesses an antiaging potential with cognitive enhancing activity. As mountain cultivated ginseng (MCG) is cultivated without agricultural chemicals, MCG has emerged as a popular herb medicine. However, little is known about the MCG-mediated pharmacological mechanism on brain aging. MethodsAs we demonstrated that glutathione peroxidase (GPx) is important for enhancing memory function in the animal model of aging, we investigated the role of MCG as a GPx inducer using GPx-1 (a major type of GPx) knockout (KO) mice. We assessed whether MCG modulates redox and cholinergic parameters, and memory function in aged GPx-1 knockout KOmice. ResultsRedox burden of aged GPx-1 KO mice was more evident than that of aged wild-type (WT) mice. Alteration of Nrf2 DNA binding activity appeared to be more evident than that of NFκB DNA binding activity in aged GPx-1 KO mice. Alteration in choline acetyltransferase (ChAT) activity was more evident than that in acetylcholine esterase activity. MCG significantly attenuated reductions in Nrf2 system and ChAT level. MCG significantly enhanced the co-localization of Nrf2-immunoreactivity and ChAT-immunoreactivity in the same cell population. Nrf2 inhibitor brusatol significantly counteracted MCG-mediated up-regulation in ChAT level and ChAT inhibition (by k252a) significantly reduced ERK phosphorylation by MCG, suggesting that MCG might require signal cascade of Nrf2/ChAT/ERK to enhance cognition. ConclusionGPx-1 depletion might be a prerequisite for cognitive impairment in aged animals. MCG-mediated cognition enhancement might be associated with the activations of Nrf2, ChAT, and ERK signaling cascade.

Modulation of striatal glutamatergic, dopaminergic and cholinergic neurotransmission pathways concomitant with motor disturbance in rats with kaolin-induced hydrocephalus

BackgroundHydrocephalus is characterized by abnormal accumulation of cerebrospinal fluid in the cerebral ventricles and causes motor impairments. The mechanisms underlying the motor changes remain elusive. Enlargement of ventricles compresses the striatum of the basal ganglia, a group of nuclei involved in the subcortical motor circuit. Here, we used a kaolin-injection juvenile rat model to explore the effects of acute and chronic hydrocephalus, 1 and 5 weeks post-treatment, respectively on the three major neurotransmission pathways (glutamatergic, dopaminergic and cholinergic) in the striatum.MethodsRats were evaluated for motor impairments. Expressions of presynaptic and postsynaptic protein markers related to the glutamatergic, dopaminergic, and cholinergic connections in the striatum were evaluated. Combined intracellular dye injection and substance P immunohistochemistry were used to distinguish between direct and indirect pathway striatal medium spiny neurons (d and i-MSNs) for the analysis of their dendritic spine density changes.ResultsHydrocephalic rats showed compromised open-field gait behavior. However, male but not female rats displayed stereotypic movements and compromised rotarod performance. Morphologically, the increase in lateral ventricle sizes was greater in the chronic than acute hydrocephalus conditions. Biochemically, hydrocephalic rats had significantly decreased striatal levels of synaptophysin, vesicular glutamate transporter 1, and glutamatergic postsynaptic density protein 95, suggesting a reduction of corticostriatal excitation. The expression of GluR2/3 was also reduced suggesting glutamate receptor compositional changes. The densities of dendritic spines, morphological correlates of excitatory synaptic foci, on both d and i-MSNs were also reduced. Hydrocephalus altered type 1 (DR1) and 2 (DR2) dopamine receptor expressions without affecting tyrosine hydroxylase level. DR1 was decreased in acute and chronic hydrocephalus, while DR2 only started to decrease later during chronic hydrocephalus. Since dopamine excites d-MSNs through DR1 and inhibits i-MSNs via DR2, our findings suggest that hydrocephalus downregulated the direct basal ganglia neural pathway persistently and disinhibited the indirect pathway late during chronic hydrocephalus. Hydrocephalus also persistently reduced the striatal choline acetyltransferase level, suggesting a reduction of cholinergic modulation.ConclusionsHydrocephalus altered striatal glutamatergic, dopaminergic, and cholinergic neurotransmission pathways and tipped the balance between the direct and indirect basal ganglia circuits, which could have contributed to the motor impairments in hydrocephalus.

Cognitive impairment induced by sevoflurane anesthesia is mediated by the cholinergic system after gastrointestinal surgery in older patients: A randomized, controlled trial

AbstractDelayed neurocognitive recovery after surgery is associated with increased morbidity and mortality. However, its mechanism of action remains controversial and complex. A prospective, double‐blind, randomized controlled trial was performed at the Affiliated Hospital of Zunyi Medical University. Older patients (aged 65 years and older) who underwent gastrointestinal surgery were randomly divided into sevoflurane‐based or propofol‐based anesthesia groups. The Mini‐Mental State Examination was performed to evaluate cognitive function. Peripheral venous blood was collected to test the levels of choline acetyltransferase and acetylcholinesterase. A total of 75 patients were enrolled and 30 patients in each group completed the study. On Day 1 postoperation, patients in the sevoflurane group showed worse performance on the Mini‐Mental State Examination than patients in the propofol group. Lower blood choline acetyltransferase concentrations and higher acetylcholinesterase concentrations were observed in patients who had sevoflurane anesthesia than in patients who had propofol anesthesia 1 day postoperative. At 3 days postoperation, patients with sevoflurane‐ or propofol‐based general anesthesia did not differ regardless of Mini‐Mental State Examination score or choline acetyltransferase and acetylcholinesterase levels. Sevoflurane‐based anesthesia has short‐term delayed neurocognitive recovery in older surgical patients, which may be related to central cholinergic system degeneration.

Mesenchymal stromal cells alleviate acute respiratory distress syndrome through the cholinergic anti-inflammatory pathway

Mesenchymal stromal cells (MSCs) have been considered a promising alternative for treatment of acute respiratory distress syndrome (ARDS). However, there is significant heterogeneity in their therapeutic efficacy, largely owing to the incomplete understanding of the mechanisms underlying the therapeutic activities of MSCs. Here, we hypothesize that the cholinergic anti-inflammatory pathway (CAP), which is recognized as a neuroimmunological pathway, may be involved in the therapeutic mechanisms by which MSCs mitigate ARDS. Using lipopolysaccharide (LPS) and bacterial lung inflammation models, we found that inflammatory cell infiltration and Evans blue leakage were reduced and that the expression levels of choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) in lung tissue were significantly increased 6 hours after MSC infusion. When the vagus nerve was blocked or α7 nicotinic acetylcholine (ACh) receptor (α7nAChR)-knockout mice were used, the therapeutic effects of MSCs were significantly reduced, suggesting that the CAP may play an important role in the effects of MSCs in ARDS treatment. Our results further showed that MSC-derived prostaglandin E2 (PGE2) likely promoted ACh synthesis and release. Additionally, based on the efficacy of nAChR and α7nAChR agonists, we found that lobeline, the nicotinic cholinergic receptor excitation stimulant, may attenuate pulmonary inflammation and alleviate respiratory symptoms of ARDS patients in a clinical study (ChiCTR2100047403). In summary, we reveal a previously unrecognized MSC-mediated mechanism of CAP activation as the means by which MSCs alleviate ARDS-like syndrome, providing insight into the clinical translation of MSCs or CAP-related strategies for the treatment of patients with ARDS.

Compound Chaijin Jieyu Tablets ameliorating insomnia complicated with depression by improving synaptic plasticity via regulating orexin A, melatonin, and acetylcholine contents

To investigate the efficacy and mechanism of action of Compound Chaijin Jieyu Tablets (复方柴金解郁片, CCJJYT) in rats with insomnia complicated with depression. Seventy-two Sprague-Dawley rats were randomly assigned into eight groups: the control, chronic unpredictable mild stress (CUMS), sleep deprivation (SD), CUMS + SD, positive drug (venlafaxine hydrochloride + diazepam), CCJJYT high-dose (CCJJYT˗2×), medium-dose (CCJJYT˗1×), and low-dose (CCJJYT˗0.5×) groups, with nine rats in each group. Depression-like behavior was evaluated by body weight, food intake, and behavioral tests such as the sucrose preference test (SPT), open field test (OFT), forced swimming test (FST), and pentobarbital-induced sleep test (PST). Hematoxylin-eosin (HE) staining and Golgi-Cox staining were used to observe changes in pathological tissue and synaptic morphology, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to detect the contents of orexin-A and acetylcholine. The expression levels of orexin receptor 1 (OXR1), melatonin receptor 1 (MT1A), melatonin receptor 2 (MT1B), acetylcholinesterase (AChE), and choline acetyltransferase (ChAT) were detected by immunohistochemistry and Western blot. In the present study, rats in the model group showed significant behavioral changes as well as a reduction in hippocampal dendritic branch length and synaptic number, along with increasing the content of orexin A and acetylcholine ( P < 0.05), and altered expression levels of OX1R, MT1A, MT1B, ChAT, and AChE in the hippocampus and prefrontal cortex after modeling ( P < 0.05). CCJJYT can improve depressive insomnia behavior and synaptic plasticity of rats ( P < 0.05), which is similar to that of the positive drug group. It can also decrease the content of orexin A and acetylcholine, and reduce the expression levels of OXR1 and ChAT in hippocampus and prefrontal cortex ( P < 0.05), and increase the expression levels of MT1A, MT1B, and AChE proteins ( P < 0.05). CCJJYT has good antidepressant and insomnia effects, probably through the regu-lation of orexin-A, melatonin, and acetylcholine content in hippocampus and prefrontal cortex of rats, improving synaptic plasticity and thus exerting antidepressant and insomnia effects.

Walnut Prevents Cognitive Impairment by Regulating the Synaptic and Mitochondrial Dysfunction via JNK Signaling and Apoptosis Pathway in High-Fat Diet-Induced C57BL/6 Mice.

This study was conducted to evaluate the protective effect of Juglans regia (walnut, Gimcheon 1ho cultivar, GC) on high-fat diet (HFD)-induced cognitive dysfunction in C57BL/6 mice. The main physiological compounds of GC were identified as pedunculagin/casuariin isomer, strictinin, tellimagrandin I, ellagic acid-O-pentoside, and ellagic acid were identified using UPLC Q-TOF/MS analysis. To evaluate the neuro-protective effect of GC, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2′,7′-dichlorodihydrofluorecein diacetate (DCF-DA) analysis were conducted in H2O2 and high glucose-induced neuronal PC12 cells and hippocampal HT22 cells. GC presented significant cell viability and inhibition of reactive oxygen species (ROS) production. GC ameliorated behavioral and memory dysfunction through Y-maze, passive avoidance, and Morris water maze tests. In addition, GC reduced white adipose tissue (WAT), liver fat mass, and serum dyslipidemia. To assess the inhibitory effect of antioxidant system deficit, lipid peroxidation, ferric reducing antioxidant power (FRAP), and advanced glycation end products (AGEs) were conducted. Administration of GC protected the antioxidant damage against HFD-induced diabetic oxidative stress. To estimate the ameliorating effect of GC, acetylcholine (ACh) level, acetylcholinesterase (AChE) activity, and expression of AChE and choline acetyltransferase (ChAT) were conducted, and the supplements of GC suppressed the cholinergic system impairment. Furthermore, GC restored mitochondrial dysfunction by regulating the mitochondrial ROS production and mitochondrial membrane potential (MMP) levels in cerebral tissues. Finally, GC ameliorated cerebral damage by synergically regulating the protein expression of the JNK signaling and apoptosis pathway. These findings suggest that GC could provide a potential functional food source to improve diabetic cognitive deficits and neuronal impairments.

Fast Alpha Activity in EEG of Patients With Alzheimer's Disease Is Paralleled by Changes in Cognition and Cholinergic Markers During Encapsulated Cell Biodelivery of Nerve Growth Factor.

BackgroundBasal forebrain cholinergic neurons are dependent on nerve growth factor (NGF) for growth and survival and these cells are among the first to degenerate in Alzheimer’s disease (AD). Targeted delivery of NGF has been suggested as a potential therapy for AD. This hypothesis was tested in a clinical trial with encapsulated cell biodelivery of NGF (NGF-ECB) in AD patients. Three of six patients showed improved biomarkers for cognition by the end of the study. Here, we report on the effects of targeted delivery of NGF on human resting EEG.Materials and methodsNGF-ECB implants were implanted bilaterally in the basal forebrain of six AD patients for 12 months. EEG recordings and quantitative analysis were performed at baseline, 3 and 12 months of NGF delivery, and analyzed for correlation with changes in Mini-mental state examination (MMSE) and levels of the cholinergic marker choline acetyltransferase (ChAT) in cerebrospinal fluid (CSF).ResultsWe found significant correlations between the topographic variance of EEG spectral power at the three study points (baseline, 3 and 12 months) and changes in MMSE and CSF ChAT. This possible effect of NGF was identified in a narrow window of alpha frequency 10–11.5 Hz, where a stabilization in MMSE score during treatment was related to an increase in EEG alpha power. A similar relation was observed between the alpha power and ChAT. More theta power at 6.5 Hz was on the contrary associated with a decrease in CSF ChAT during the trial period.ConclusionIn this exploratory study, there was a positive correlative pattern between physiological high-frequency alpha activity and stabilization in MMSE and increase in CSF ChAT in AD patients receiving targeted delivery of NGF to the cholinergic basal forebrain.

Digoxin Exhibits Neuroprotective Properties in a Rat Model of Dementia

Alzheimer's disease (AD) is by far the most common cause of cognitive impairment in older adults. Current treatments are entirely focused on the symptoms of AD. A complex etiology for AD has been proposed recently, in which AD leads in elevated levels of inflammation. We previously studied digoxin's involvement in the sporadic-AD intracerebroventricular (ICV)-streptozotocin (STZ) animal model due to its anti-inflammatory and neuroprotective characteristics. 18 adult sprague-dawley rats were split into three groups: control (n = 6), STZ + Saline (n = 6), and STZ + Digoxin (n = 6). Twelve AD-induced rats were split into two groups using stereotaxy five days after STZ injection (3mg/kg) into both lateral ventricles: one group got digoxin (0.1mg/kg/day, i.p.) for three weeks, while the other group received saline. Following treatment, each subject was subjected to a passive avoidance learning (PAL) test, followed by brain tissue harvesting. The levels of tumor necrosis factor-alpha (TNF-α) and choline acetyl transferase (ChAT) were measured in the brain, and neurons were counted using Cresyl violet staining in cornu ammonis-1 (CA1) and cornu ammonis-3 (CA3) cornu ammonis (CA3). ICV-STZ significantly shortened PAL latency, increased brain TNF-α levels, decreased brain ChAT activity, and decreased hippocampus neuron number. On the other hand, digoxin significantly reduced all of these STZ-induced deleterious effects. Digoxin significantly rescued rats from memory loss caused by ICV-STZ by decreasing hippocampal cell death, neuroinflammation, and cholinergic deficiency. These findings suggest that digoxin may be beneficial in treating cognitive impairment and Alzheimer's disease.

Slow progression of sciatic nerve degeneration and regeneration after loose ligation through microglial activation and decreased KCC2 levels in the mouse spinal cord ventral horn

Peripheral nerve injury affects motor functions. To reveal the mechanisms underlying motor dysfunction and recovery after nerve compression, which have not been precisely examined, we investigated the temporal relationship among changes in motor function, nerve histopathology, and marker molecule expression in the spinal cord after loose ligation of the mouse sciatic nerve. After ligation, sciatic motor function suddenly declined, and axons gradually degenerated. During degeneration, galanin was localized in motor neuron cell bodies. Then, in the ventral horn, microglia were activated, and expression of choline acetyltransferase (ChAT), a synthetic enzyme of acetylcholine, and potassium chloride co-transporter 2 (KCC2), which shifts the action of γ-amino butyric acid (GABA) and glycine to inhibitory, decreased. Motor function recovery was insufficient although axonal regeneration was complete. ChAT levels gradually recovered during axonal regeneration. When regeneration was nearly complete, microglial activation declined, and KCC2 expression started to increase. The KCC2 level sufficiently recovered when axonal regeneration was complete, suggesting that the excitatory action of GABA/glycine may participate in axonal regeneration. Furthermore, these changes proceeded slower than those after severance, suggesting that loose ligation, compression, may mediate slower progression of degeneration and regeneration than severance, and these changes may cause the motor dysfunction and its recovery.