Dataset Information

Inhibition of muscarinic receptor signaling protects human enteric inhibitory neurons against platin chemotherapy toxicity

ABSTRACT: Gastrointestinal toxicity is a common dose-limiting adverse effect of platin chemotherapy treatment. 50% of cancer survivors continue to experience symptoms of chronic constipation or diarrhea induced by their chemotherapy for many years after their treatment. This drug toxicity is largely attributed to damage to enteric neurons that innervate the gastrointestinal tract and control gastrointestinal motility. The mechanisms responsible for platin-induced enteric neurotoxicity and potential preventative strategies have remained unknown. Here, we use human pluripotent stem cell-derived enteric neurons to establish a new model system capable of uncovering the mechanism of platin-induced enteric neuropathy. Utilizing this scalable system, we performed a high throughput screen and identified drug candidates and pathways involved in the disease. Our analyses revealed that excitotoxicity through muscarinic cholinergic signaling is a key driver of platin-induced enteric neuropathy. Using single nuclei transcriptomics and functional assays, we discovered that this disease mechanism leads to increased susceptibility of specific neuronal subtypes, including inhibitory nitrergic neurons, to platins. Histological assessment of the enteric nervous system in platin-treated patients confirmed the selective loss of nitrergic neurons. Finally, we demonstrated that pharmacological and genetic inhibition of muscarinic cholinergic signaling is sufficient to rescue enteric neurons from platin excitotoxicity in vitro and can prevent platin-induced constipation and degeneration of nitrergic neurons in mice. These studies define the mechanisms of platin-induced enteric neuropathy and serve as a framework for uncovering cell type-specific manifestations of cellular stress underlying numerous intractable peripheral neuropathies.

ORGANISM(S): Homo sapiens

PROVIDER: GSE225871 | GEO | 2025/02/22

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other
	GSE225871_gene_count.txt.gz	Txt

Items per page:

1 - 2 of 2

Similar Datasets

Project description:The endocannabinoid system plays important roles in the modulation of gastrointestinal motility and secretions. These effects are mainly mediated by the activation by the endocannabinoids anandamide (AEA) and 2-arachidonylglycerol (2-AG) of CB1 receptors expressed on cholinergic neurons. Cannabis sativa extracts also perform these activities, through the detection of CB1 receptors by the phytocannabinoids they contain, in particular delta9-tetrahydrocannabinol. CB1 receptors are abundantly expressed at the synaptic terminals of excitatory motor neurons and cholinergic secretomotor neurons and their activation induces prejunctional inhibition of acetylcholine release. It is thought that the endocannabinoids AEA and 2-AG, by activating these receptors, may exert a physiological control on gastrointestinal contractility and secretions. This research hypothesizes that drugs capable of inhibiting the biosynthetic and catabolic enzymes of endocannabinoids, of inhibiting the transmembrane transport of endocannabinoids or of allosterically modulating CB1 receptors induce important regulating effects of basal contractility and excitatory motor responses, induced by activation of neurons intramural cholinergics, of colonic circular smooth muscle. The effects of drugs acting on CB receptors, endocannabinoid biosynthetic and catabolic enzymes and endocannabinoid membrane transporters on basal contractility or induced by neuronal activation of colonic preparations in vitro will be evaluated. The study will enroll patients affected by colorectal cancer to undergo elective resective surgery at any stage, undergoing upfront surgery or after neo-adjuvant therapy with a therapeutic interval greater than 6 weeks. In the selected patients (see inclusion/exclusion criteria), a fresh sample of about 2.5 cm of healthy colon (healthy resection margin) will be taken, which will be taken in the operating room and sent to the laboratory for in vitro study. Expected results: The study is expected to provide new evidence regarding the induction of pharmacological effects by allosteric receptor modulators of CB1 receptors, inhibitors of endocannabinoid biosynthetic and catabolic enzymes, and inhibitors of cannabinoid transporters in the human colon, which may open interesting perspectives regarding the development of new therapeutic strategies for the treatment of constipation, diarrhea and irritable bowel syndrome.

Project description:Neural control of visceral organ function is essential for homeostasis and health. Intestinal peristalsis is critical for digestive physiology and host defence and is often dysregulated in gastrointestinal (GI) disorders. Luminal factors, such as diet and microbiota regulate neurogenic programs of gut motility, but the underlying molecular mechanisms remain unclear. Here we show that the transcription factor Aryl hydrocarbon Receptor (AhR) functions as a biosensor in intestinal neural circuits linking their functional output to the microbial environment of the gut lumen. Using nuclear RNA sequencing of mouse enteric neurons representing distinct intestinal segments and microbiota states, we demonstrate that the intrinsic neural networks of the colon exhibit unique transcriptional profiles controlled by the combined effects of host genetic programmes and microbial colonisation. Microbiota-induced expression of AhR in neurons of the distal gastrointestinal tract enables them to respond to the luminal environment and induce expression of neuron-specific effector mechanisms. Neuron-specific deletion of Ahr or constitutive overexpression of its negative feedback regulator CYP1A1, results in reduced peristaltic activity of the colon, similar to that observed in microbiota-depleted mice. Finally, expression of Ahr in enteric neurons of antibiotic-treated mice partially restores intestinal motility. Taken together, our experiments identify AhR signalling in enteric neurons as a regulatory node that integrates the luminal environment with the physiological output of intestinal neural circuits towards gut homeostasis and health. The enteric nervous system (ENS) encompasses the intrinsic neural networks of the gastrointestinal (GI) tract, which regulate most aspects of intestinal physiology, including peristalsis. In addition to host-specific genetic programmes, microbiota and diet have emerged as critical regulators of gut tissue physiology and changes in the microbial composition of the lumen often accompany GI disorders. We found that gut environmental sensor Aryl hydrocarbon receptor (AhR) is induced in colonic neurons in response to microbiota colonisation and regulates intestinal peristalsis in an AhR ligand-dependent manner. In this experiment, we used RNA sequencing to identify genes regulated in mouse colonic neurons by AhR activation.

Project description:Background: Current studies provide compelling evidence that the enteric nervous system and neighboring resident macrophages in the muscularis externa modulate neuroimmune processes in the gut after abdominal surgery. While substantial knowledge exists about macrophage-enteric glia interactions, the fate of enteric neurons, which have an indispensable role in gut homeostasis and gastrointestinal motility, has not been thoroughly investigated during enteric neuroinflammation. Therefore, we investigated the impact of enteric neuron-macrophage interactions on postoperative trauma and subsequent motility disturbances, i.e., postoperative ileus. Methods: Neuroinflammation and postoperative ileus were induced in various transgenic mice by surgical manipulation of the small intestine. We studied enteric neurons and macrophage-specific transcriptomes using bulk RNA-Seq in neuron-specific RiboTag mice and sorted CX3CR1-GFP+ macrophages. To investigate their intercellular communication, we treated CX3CR1-GFP+ mice with CSFR1-antibody to deplete macrophages and subsequently induce POI through surgical trauma. These mice were examined for gastrointestinal motility, immune cell infiltration, and neuronal function. Ultimately, we validated the murine data in human gut samples collected early and late during abdominal surgery to understand the impact of surgical manipulation on patients' enteric nervous system function. Results: We detected strong neuronal activation in the early postsurgical phase, followed, after 24h, by transcriptional signatures of neuronal proliferation, neuronal death, and synaptic degradation. Neuron-specific transcriptome analysis confirmed these changes and verified the neuronal responses to the inflammatory environment. Simultaneously, our study revealed a neurodegenerative profile in macrophage-specific transcriptomes during POI. Depletion of macrophages before surgical manipulation led to decreased neuronal death, less synaptic decay, and improved GI motility, emphasizing the essential role of macrophages in neurodegeneration during intestinal neuroinflammation. In human jejunal muscularis externa samples, taken at early and late stages of pancreatectomies, we detected reactive and dying neurons with dysregulated gene expression of synaptic signaling and neurogenic processes. Conclusion: Surgical trauma and acute intestinal inflammation activate enteric neurons and induce neurodegeneration with severe synaptic decay, predominantly mediated by resident macrophages. Future studies should focus on neuroprotective mechanisms to dampen neurodegeneration and promote faster recovery from postoperative inflammation and motility disturbances.

Dataset Information

Inhibition of muscarinic receptor signaling protects human enteric inhibitory neurons against platin chemotherapy toxicity

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets