Search Results (333)

Background: Peritoneal dissemination in colorectal cancer (CRC) is associated with poor prognosis due to limited efficacy of current therapeutic strategies. The cholinergic receptor nicotinic beta 2 subunit (CHRNB2), a component of the acetylcholine receptor, has been implicated in other malignancies, but its role in CRC remains unknown. Methods: This study evaluated the expression and function of CHRNB2 in CRC. CHRNB2 mRNA levels were quantified by qRT-PCR in cell lines and clinical specimens. Functional assays were conducted using CRC cell lines with high CHRNB2 expression, in which CHRNB2 was knocked down by shRNA. Cell proliferation, migration, and invasion were assessed in vitro. In vivo effects were evaluated using subcutaneous and peritoneal xenograft models. The impact of CHRNB2 monoclonal antibody (mAb) treatment on CRC cell proliferation was also examined. Clinical correlations were assessed between CHRNB2 expression and clinicopathological features, including recurrence patterns. Results: CHRNB2 expression varied among CRC cell lines, with the highest levels observed in LOVO cells. CHRNB2 knockdown significantly inhibited proliferation, migration, and invasion in vitro and suppressed tumor growth in vivo. CHRNB2 mAb treatment reduced cell proliferation. Clinically, high CHRNB2 expression correlated with a significantly higher cumulative rate of peritoneal recurrence, but not with recurrence in the liver, lungs, or lymph nodes. Multivariate analysis identified high CHRNB2 expression and T4 tumor depth as independent predictors of peritoneal recurrence. Conclusions: CHRNB2 promotes the malignant phenotype of CRC, particularly in peritoneal dissemination. These findings suggest that CHRNB2 may serve as a novel diagnostic biomarker and therapeutic target for CRC with peritoneal metastasis. Full article

In familial Alzheimer’s disease (FAD), presenilin 1 (PSEN1) E280A cholinergic-like neurons (ChLNs) induce aberrant secretion of extracellular amyloid beta (eAβ). How PSEN1 E280A ChLNs-eAβ affects microglial activity is still unknown. We obtained induced microglia-like cells (iMG) from human peripheral blood cells (hPBCs) in a 15-day differentiation process to investigate the effect of bolus addition of Aβ42, PSEN1 E280A cholinergic-like neuron (ChLN)-derived culture supernatants, and PSEN1 E280A ChLNs on wild type (WT) iMG, PSEN1 E280A iMG, and sporadic Alzheimer’s disease (SAD) iMG. We found that WT iMG cells, when challenged with non-cellular (e.g., lipopolysaccharide, LPS) or cellular (e.g., Aβ42, PSEN1 E280A ChLN-derived culture supernatants) microenvironments, closely resemble primary human microglia in terms of morphology (resembling an “amoeboid-like phenotype”), expression of surface markers (Ionized calcium-binding adapter molecule 1, IBA-1; transmembrane protein 119, TMEM119), phagocytic ability (high pHrodo™ Red E. coli BioParticles™ phagocytic activity), immune metabolism (i.e., high generation of reactive oxygen species, ROS), increase in mitochondrial membrane potential (ΔΨm), response to ATP-induced transient intracellular Ca²⁺ influx, cell polarization (cluster of differentiation 68 (CD68)/CD206 ratio: M1 phenotype), cell migration activity according to the scratch wound assay, and especially in their inflammatory response (secretion of cytokine interleukin-6, IL-6; Tumor necrosis factor alpha, TNF-α). We also found that PSEN1 E280A and SAD iMG are physiologically unresponsive to ATP-induced Ca²⁺ influx, have reduced phagocytic activity, and diminished expression of Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) protein, but when co-cultured with PSEN1 E280A ChLNs, iMG shows an increase in pro-inflammatory phenotype (M1) and secretes high levels of cytokines IL-6 and TNF-α. As a result, PSEN1 E280A and SAD iMG induce apoptosis in PSEN1 E280A ChLNs as evidenced by abnormal phosphorylation of protein TAU at residue T205 and cleaved caspase 3 (CC3). Taken together, these results suggest that PSEN1 E280A ChLNs initiate a vicious cycle between damaged neurons and M1 phenotype microglia, resulting in excessive ChLN death. Our findings provide a suitable platform for the exploration of novel therapeutic approaches for the fight against FAD. Full article

Choline has been recognized as an essential nutrient involved in various physiological functions critical to human health. Adequate daily intake of choline has been established by the US National Academy of Medicine in 1998, considering choline requirements for different ages, sex differences and physiological states (e.g., pregnancy). By serving as a precursor for acetylcholine and phospholipids, choline is important for cholinergic transmission and the structural integrity of cell membranes. In addition, choline is involved in lipid and cholesterol transport and serves as a methyl donor after oxidation to betaine. Extracellular choline is transported across the cell membrane via various transport systems (high-affinity and low-affinity choline transporters) with distinct features and roles. An adequate dietary intake of choline during pregnancy supports proper fetal development, and throughout life supports brain, liver, and muscle functions, while choline deficiency is linked to disease states like fatty liver. Choline has important roles in neurodevelopment, cognition, liver function, lipid metabolism, and cardiovascular health. While its signaling role has been considered mostly indirect via acetylcholine and phosphatidylcholine which are synthesized from choline, emerging evidence supports a role for choline as an intracellular messenger acting on Sigma-1R, a non-opioid intracellular receptor. These new findings expand the cell signaling repertoire and increase the current understanding of the role of choline while warranting more research to uncover the molecular mechanisms and significance in the context of GPCR signaling, the relevance for physiology and disease states. Full article

The hypothalamus belongs to the central brain structure designed for the neuroendocrine regulation of many organismal functions, including the stress response, cardiovascular system, and blood pressure, and it is well known that the serotonergic hypothalamic system plays a significant role in these processes. Unfortunately, the genetic determination of serotonergic hypothalamic mechanisms has been little studied. The aim of this article is to describe the expression profile of the genes in the hypothalamic serotonergic synapses in hypertensive ISIAH rats in comparison with normotensive WAG rats in control conditions and under the influence of a single short-term restraint stress. It was found that 14 differentially expressed genes (DEGs) may provide the inter-strain differences in the serotonergic synaptic function in the hypothalamus between the hyper- and normotensive rats studied. In hypertensive rats, downregulation of Slc18a1 gene in the presynaptic serotoninergic ends and decreased expression of Cacna1s and Htr3a genes determining the postsynaptic membrane conductance may be considered as a main factors causing differences in the function of hypothalamic serotoninergic synapses in hypertensive ISIAH and normotensive WAG rats at the basal conditions. Under basal conditions, glial cell genes were not involved in the formation of inter-strain differences in serotonergic synaptic function. The analysis of transcriptional responses to restraint stress revealed key genes whose expression is involved in the regulation of serotonergic signaling, and a cascade of interrelated changes in biological processes and metabolic pathways. Stress-dependent changes in the expression of some DEGs are similar in the hypothalamus of hypertensive and normotensive rats, but the expression of a number of genes changes in a strain-specific manner. The results suggest that in hypothalamic glial cells of both strains, restraint stress induces changes in the expression of DEGs associated with the synthesis of Ip3 and its receptors. Many of the identified serotonergic DEGs participate in the regulation of not only serotonergic synapses but may also be involved in the regulation of cholinergic, GABAergic, glutamatergic, and dopaminergic synapses. The results of the study provide new information on the genetic mechanisms of inter-strain differences in the functioning of the hypothalamic serotonergic system in hypertensive ISIAH and normotensive WAG rats at rest and under the influence of a single short-term restraint (emotional) stress. Full article

Background/Objectives: Passiflora (passionflower), traditionally used for anxiety and insomnia, is primarily known for GABAergic modulation. However, evidence suggests broader neuropharmacological actions. This review aimed to systematically explore non-GABAergic mechanisms of Passiflora. Methods: We performed a systematic review following PRISMA Guidelines (PROSPERO: CRD420251028681). PubMed/Medline, PsycINFO, Embase, Web of Science, and Scopus were searched for original research on non-GABA neurobiological mechanisms of Passiflora species (P. incarnata, P. edulis, P. caerulea, P. actinia, P. foetida). Studies were screened and assessed for eligibility, and data on design, Passiflora preparation, mechanisms, and main findings were extracted. Results: Thirteen studies revealed diverse non-GABAergic actions. Passiflora modulates opioidergic and nicotinic cholinergic systems (relevant to analgesia), monoaminergic pathways (affecting dopamine, norepinephrine, serotonin), and the glutamatergic system (offering neuroprotection via NMDA receptor inhibition). It also exhibits significant anti-inflammatory and antioxidant effects (reducing cytokines, activating Nrf2) and modulates the HPA axis (reducing stress hormones). Other mechanisms include gut microbiota modulation and metabolic effects. Conclusions: Passiflora’s therapeutic potential extends beyond GABA, involving multiple neurotransmitter systems and neuroprotective, anti-inflammatory, antioxidant, and HPA axis-regulating activities. This multi-target profile likely contributes to its clinical efficacy in conditions like anxiety, pain, and stress, potentially with a favorable side-effect profile. Further research, including mechanistic studies and clinical trials with relevant biomarkers, is needed to fully elucidate its complex pharmacology. Full article

Autonomic imbalance is one of the major pathological disturbances in chronic heart failure (CHF). Additionally, enhanced oxidative stress and inflammation are considered to be the main contributors to the disease progression. A growing body of evidence suggests cholinergic stimulation as a potential therapeutic approach in CHF, since it corrects the autonomic imbalance and alters the inflammatory response via the cholinergic anti-inflammatory pathway. Although previous research has provided some insights into the potential mechanisms behind these effects, there is a gap in knowledge regarding different cholinergic stimulation methods and their specific mechanisms of action. In the present study, an isoprenaline model (5 mg/kg/day s.c. for 7 days, followed by 4 weeks of CHF development) was used. Afterwards, rats received pyridostigmine (22 mg/kg/day in tap water for 14 days) or no treatment. Pyridostigmine treatment prevented the progression of CHF, decreasing chamber wall thinning (↑ PWDd, ↑ PWDs) and left ventricle dilatation (↓ LVIDd, ↓ LVIDs), thus improving cardiac contractile function (↑ EF). Additionally, pyridostigmine improved antioxidative status (↓ TBARS, ↓ NO₂⁻; ↑ CAT, ↑ GSH) and significantly reduced cardiac fibrosis development, confirmed by pathohistological findings and biochemical marker reduction (↓ MMP2, ↓ MMP9). However, further investigations are needed to fully understand the exact cellular mechanisms involved in the CHF attenuation via pyridostigmine. Full article

Alcohol is a prevalent psychoactive substance and a risk factor for developing injuries and non-communicable diseases, representing a significant health and economic burden. Alcohol involves numerous molecular pathways. Its metabolism is regulated by alcohol dehydrogenases and aldehyde dehydrogenases; it also stimulates cholinergic interneurons, increasing the sensitivity of 5-HT3 receptors, while chronic alcohol consumption alters the mesolimbic dopaminergic system involved in reward processing. The treatment of alcohol use disorder (AUD) is essential to manage complex patients, following an evidence-based approach. The aim of this narrative review is to provide a clear and practical summary to support and assist healthcare professionals in the Italian context. Approved pharmacological treatments for AUD include oral naltrexone and acamprosate, sodium oxybate, disulfiram, and nalmefene. Off-label therapies include baclofen, topiramate, gabapentin, pregabalin, ondansetron, and cytisine. A more informed clinical and practical approach that understands the altered neuronal signaling pathways is essential for offering effective, efficient, appropriate, and safe therapeutic algorithms for complex patients with alcohol use disorder. A comprehensive framework should include integrated treatments with a personalized approach. Full article

Cholinergic projections from the basal forebrain to the cortex and hippocampus play a critical role in cognitive functions, many of which rely on signaling through the alpha7 nicotinic acetylcholine receptor (α7nAChR). The Alzheimer’s disease (AD) brain is characterized by the profound impairment of the basal forebrain cholinergic system, including alterations in the levels of α7nAChR in various brain areas. In addition, α7nAChR binds with high affinity to beta amyloid (Aβ), suggesting α7nAChR might mediate some of Aβ’s effects in the brain. Under normal physiological conditions, the interaction between Aβ and α7nAChR appears to be beneficial, supporting normal neurotransmission, synaptic plasticity, and memory functions. However, when levels of Aβ are pathologically elevated, their interaction leads to deleterious effects, implicating α7nAChR in the pathophysiology of AD. In addition to expression in neurons, α7nAChR is expressed in astrocytes and microglia, where it serves as a key component of a cholinergic pathway that regulates neuroinflammation. This review article will cover the role of α7nAChR in neurons, astrocytes and microglia under normal conditions, summarize changes in the expression or function of α7nAChR in neurons and glia in the AD brain, and discuss cell-type specific contributions of α7nAChR to AD pathology with an emphasis on interactions of α7nAChR with Aβ. Full article

Delta-9-tetrahydrocannabinol (THC) is a psychoactive element of Cannabis sativa and affects the human cannabinoid system through its receptors, CB1R and CB2R. CB1R was found in several brain areas, including the hippocampal formation (HF), and it is responsible for most THC side effects. We investigated THC’s effects in the HF of female Wistar rats to assess changes in its neurotransmission. Female Wister rats (n = 20) were gonadectomized under anesthesia at 8 weeks old. Afterwards, they received estradiol benzoate (EB) and/or THC. Immunohistochemistry was performed to assess the expression of the cholinergic receptor alpha 7 subunit (CHRNA7), the vesicular acetylcholine transporter (VAChT), the vesicular glutamate transporter (VGLUT), the gamma-aminobutyric acid type A receptor (GABRA), the CB1 receptor, and estradiol receptor alpha (EBα). In the HF, the expression of CHRNA7 was increased by EB and by THC in the Oil groups but decreased by THC in the EB groups. The same is true for VGLUT expression in the DG and hilum and for GABRA expression in the hilum. The expression of VAChT and CB1 is reduced by EB, while the concomitant administration of THC increases it. GAD expression is reduced by EB administration in CA1, CA3, and DG. Our results may help with decision-making regarding the prescription of low doses of THC as a therapeutical approach. Full article

Cognitive problems are associated with impaired learning ability and memory dysfunction. Neuroinflammation has been identified as an important factor in the progression of anxiety and depressive disorders. Zingerone is a phenolic alkanone derived from ginger (Zingiber officinale Roscoe), which is known for its antioxidant and anti-inflammatory properties. A number of studies have investigated the effect of zingerone on neuroinflammation and cognitive impairment. However, this evidence has not been systematically reviewed. This study sought to systematically review the effect of zingerone on neuroinflammation and neurobehavioural changes associated with memory and learning impairment and anxiety-like and depressive-like behaviours. A systematic review was conducted using pre-defined search criteria on Google Scholar, Scopus and Web of Science. The records obtained were screened based on inclusion criteria, and data was extracted from the included studies. Out of the 482 studies that were identified, only 9 studies met the inclusion criteria. Neuroinflammatory markers such as interleukin 1β (IL-1β), interleukin 6 (IL-6), tumour necrosis factor-alpha (TNF-α) and ionized calcium binding adaptor molecule (IBA-1), as well as behavioural parameters including Morris water maze, Y-Maze, recognition test, passive avoidance test, elevated plus maze, sucrose preference test and forced swimming test were measured. Zingerone exhibited anti-neuroinflammatory effects by improving IL-1β, IL-6 and TNF-α levels. However, zingerone did not show any significant changes on activated microglia. The anti-neuroinflammatory mechanisms of zingerone were linked to the inhibition of nuclear factor kappa B (NF-kB) activation and the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome, as well as the reduction in neuronal nitric oxide synthase (nNOS). The anxiolytic and anti-depressive effects of zingerone were also associated with an improvement in cortical cholinergic transmission, the mitigation of oxidative stress and the upregulation of neurotransmitters such as serotonin and dopamine. This review provides scientific evidence on the cognitive enhancing and neuroprotective mechanisms of zingerone, which may be beneficial for future experimental investigations. Full article

α7 nAChRs are known to modulate several physiological and pathological functions in glial cells, and their selective activation might have anti-inflammatory effects in the central and peripheral nervous system. OL progenitors (OPCs) respond to cholinergic stimuli via muscarinic receptors that are mainly involved in the modulation of their proliferation. Conversely, the role of nicotinic receptors, particularly α7 nAChRs, has been poorly investigated. In this study, we evaluated the expression of α7 nAChRs in a model of OPCs (Oli neu) and the potential effects mediated by their selective activation. Methods: Oli neu cells were used as a murine immortalized OPCs model. The effects of α7 nAChRs stimulation on cell proliferation and survival were assessed by the MTT assay. RT-PCR and Western blot analysis were used to analyze the expression of α7 nAChRs and proliferative and differentiative markers (PCNA, MBP). LPS exposure was used to induce the environment in which the antioxidant and anti-inflammatory properties of α7 nAChRs were analyzed, evaluating NFR2 and TNF-α expression, ROS levels through DCFDA staining while Oil Red O staining was used for the analysis of lipid droplet content as a marker of cellular inflammation response. Results: The α7 nAChR is expressed both in OPCs and OLs, and its stimulation by the selective agonist ICH3 increases cell proliferation without modifying the OLs’ differentiation capability. Moreover, ICH3 showed anti-inflammatory and antioxidant effects against LPS exposure. Conclusions: The results herein obtained confirm the role of α7 nAChR in the modulation of neuroinflammatory processes as well as their protective effects on OLs. Full article

The gastrointestinal (GI) tract is under neural, endocrine and paracrine control. The release (basal and in the presence of either cholinergic and opioid antagonists) of Met-enkephalin, insulin-like growth factor 1 (IGF-1) and somatostatin (SRIF) was determined quantitatively in vitro using explants of the crop, proventriculus and duodenum from either day 0 or day 1 chicks. In addition, the effects of cholinergic and opioid antagonists on PENK gene expression were examined. Thus, the aim of this study was to determine the roles of cholinergic and opioid receptors in the GI tract in newly hatched chickens. Moreover, the effect of IGF-1 and Met-enkephalin on cell division in duodenal explants in vitro was determined. There was both the release of Met-enkephalin from, and PENK expression in, the explants of the crop, proventriculus and duodenum tissue. This is the first report of any neuropeptide(s) being synthesized in and/or released from the crop. In vitro release of Met-enkephalin, IGF-1 and SRIF from duodenal and proventriculus explants was influenced (p < 0.01) by either cholinergic or opioid antagonists; for instance, in the presence of atropine, decreases (p < 0.001) of 17.8% and 57.7% are seen, respectively, in Met-enkephalin release and PENK expression in crop explants from day 1 chicks. Moreover, in the presence of atropine, there were increases (p < 0.001) of 47.7% and 70.9% in IGF-1 release in proventriculus explants from, respectively, day 0 and day 1 chicks. Met-enkephalin and/or IGF-1 stimulated the cell division of duodenal explants in vitro. This is the first report of Met-enkephalin release and PENK expression in the avian crop and of the effects of cholinergic or opioid antagonists on these factors. It is also the first report of either cholinergic or opioid control of IGF-1 release in the periphery of any species. There were strong relationships (p < 0.05) between the release of Met-enkephalin and that of IGF-1 in the duodenum and between the release of SRIF and that of IGF-1 in the proventriculus. This is the first report of IGF-1 and Met-enkephalin stimulating (p < 0.001) the proliferation of duodenal cells and, together, exerting a synergist effect. It is concluded that the release of Met-enkephalin, IGF-1 and SRIF from foregut regions is under tonic cholinergic and opioid control. Full article

It has long been recognised that airway smooth muscle cells (ASMCs) possess an abundance of M2 muscarinic receptors (M2Rs). However, the contribution of postjunctional M2Rs to contractions of airway smooth muscle (ASM) induced by the release of acetylcholine (ACh) from parasympathetic nerves was thought to be minimal. Instead, it was believed that these responses were exclusively mediated by activation of M3Rs. However, evidence is emerging that postjunctional M2Rs may have a greater role than previously realised. In this review, we discuss ACh signalling in airways, highlighting the well-established autoinhibitory role of prejunctional M2Rs and the putative roles of postjunctional M2Rs to cholinergic contractions of ASM. The cellular mechanisms that underpin M2R-dependent contractions of ASM are reviewed, with a particular emphasis on the role of ion channels in these responses. The regulation of M2R signalling pathways by β-adrenoceptor activation is also considered, along with the potential involvement of postjunctional M2Rs in airway diseases such as asthma and chronic obstructive pulmonary disease (COPD). Full article

Alzheimer’s disease (AD) is characterized by the progressive loss of cognitive function and is frequently accompanied by neuropsychiatric symptoms (NPS). Pathologically, AD is defined by two hallmark features: the extracellular accumulation of β-amyloid and the intracellular hyperphosphorylation of the tau protein. In addition to these primary changes, several other abnormalities are associated with the disease, including neuroinflammation, synaptic loss, oxidative stress, neurotransmitter imbalance, and genetic and epigenetic alterations. NPS in AD encompass a range of symptoms, such as anxiety, apathy, agitation, depression, and psychosis. These symptoms are thought to arise partly from the damage caused by the pathological hallmarks of AD, which impair various neurotransmitter systems. Altered levels of several neurotransmitters, including gamma-aminobutyric acid (GABA), serotonin (5-HT), dopamine (DA), and the cholinergic and noradrenergic systems, have been implicated in the development of agitation. Additionally, reduced endocannabinoid system (ECS) functionality, particularly cannabinoid receptor 1 (CB1R), has been linked to neurobehavioral alterations. Preclinical studies suggest that a decrease in CB1R levels is associated with aggressive behavior, and CB1R agonists have demonstrated beneficial effects in alleviating agitation and related symptoms. Given these findings, the current review focuses on the therapeutic potential of targeting neurotransmitter systems and CB1R dysfunction to manage agitation in AD. Full article

We have previously shown that neuromodulatory actions on astrocytes can elicit metabotropic glutamate- and N-methyl-D-aspartate receptor-dependent tonic changes in excitability in the mesopontine region. Although in vitro experiments explored robust effects, the in vivo significance of our findings remained unknown. In this project, chronic chemogenetic activation of mesopontine astrocytes and its actions on movement, circadian activity, acoustic startle and spatial memory were tested. The control group of young adult male mice where mesopontine astrocytes expressed only the mCherry fluorescent tag was compared to the group expressing the hM3D(Gq) chemogenetic actuator. Chronic chemogenetic astrocyte activation reduced the amplitude of the acoustic startle reflex and increased the locomotion speed in the resting period. Gait alterations were also demonstrated but no change in the spatial memory was explored. As a potential background of these findings, chronic astrocytic activation decreased the cholinergic neuronal number to 54% and reduced the non-cholinergic neuronal number to 76% of the control. In conclusion, chronic astrocytic activation and the consequential decrease in the neuronal number led to disturbances in movement and circadian activity resembling brainstem-related symptoms of progressive supranuclear palsy, raising the possibility that astrocytic overactivation is involved in the pathogenesis of this disease. Full article