Autophagy-related 16-like 1 is influenced by human herpes virus 1-encoded microRNAs in biopsy samples from the lower esophageal sphincter muscle during per-oral endoscopic myotomy for esophageal achalasia

Role of mechanoregulation in mast cell-mediated immune inflammation of the smooth muscle in the pathophysiology of esophageal motility disorders

Major esophageal disorders involve obstructive transport of bolus to the stomach, causing symptoms of dysphagia and impaired clearing of the refluxed gastric contents. These may occur due to mechanical constriction of the esophageal lumen or loss of relaxation associated with deglutitive inhibition, as in achalasia-like disorders. Recently, immune inflammation has been identified as an important cause of esophageal strictures and the loss of inhibitory neurotransmission. These disorders are also associated with smooth muscle hypertrophy and hypercontractility, whose cause is unknown. This review investigated immune inflammation in the causation of smooth muscle changes in obstructive esophageal bolus transport. Findings suggest that smooth muscle hypertrophy occurs above the obstruction and is due to mechanical stress on the smooth muscles. The mechanostressed smooth muscles release cytokines and other molecules that may recruit and microlocalize mast cells to smooth muscle bundles, so that their products may have a close bidirectional effect on each other. Acting in a paracrine fashion, the inflammatory cytokines induce genetic and epigenetic changes in the smooth muscles, leading to smooth muscle hypercontractility, hypertrophy, and impaired relaxation. These changes may worsen difficulty in the esophageal transport. Immune processes differ in the first phase of obstructive bolus transport, and the second phase of muscle hypertrophy and hypercontractility. Moreover, changes in the type of mechanical stress may change immune response and effect on smooth muscles. Understanding immune signaling in causes of obstructive bolus transport, type of mechanical stress, and associated smooth muscle changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.NEW & NOTEWORTHY Esophageal disorders such as esophageal stricture or achalasia, and diffuse esophageal spasm are associated with smooth muscle hypertrophy and hypercontractility, above the obstruction, yet the cause of such changes is unknown. This review suggests that smooth muscle obstructive disorders may cause mechanical stress on smooth muscle, which then secretes chemicals that recruit, microlocalize, and activate mast cells to initiate immune inflammation, producing functional and structural changes in smooth muscles. Understanding the immune signaling in these changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.

HCMV miR-UL70-3p downregulates the rapamycin-induced autophagy by targeting the autophagy-related protein 9A (ATG9A)

Human cytomegalovirus (HCMV) is a representative β-herpesvirus that establishes persistent infections in humans, and exhibits high seropositivity rates in adults. It has co-evolved with its human host and employs various strategies to evade antiviral mechanisms by utilizing a significant portion of its genome. HCMV-encoded proteins and miRNAs have been implicated in regulating these mechanisms, enabling viral survival within the human body. During viral infections, autophagy, a conserved catabolic process essential for cellular homeostasis, acts as an antiviral defense mechanism. Multiple studies have reported that HCMV can modulate autophagy through its proteins and miRNAs, thereby influencing its survival within the host. In this study, we showed the potential involvement of HCMV miRNAs in cellular autophagy. We employed various bioinformatic tools to predict putative HCMV miRNAs that target autophagy-related genes and their corresponding cellular autophagy genes. Our results show that the 3'UTR of autophagy-related genes, including ATG9A, ATG9B, ATG16L2, SQSTM1, and EIF2AK2, harbors potential binding sites for hcmv-miR-UL70-3p. Experimental manipulation involving ectopic expression of hcmv-miR-UL70-3p demonstrated a significant reduction in rapamycin-induced autophagy, with ATG9A as its functional target. These findings establish that hcmv-miR-UL70-3p acts as an autophagy inhibitor by suppressing the expression of ATG9A.

Achalasia: investigation and management

Achalasia, characterised by the absence of peristalsis and failure of relaxation of the lower oesophageal sphincter, is an uncommon degenerative condition that results in dysphagia. If left untreated it can lead to aspiration, oesophageal perforation, oesophagitis and malnutrition. It has a range of immune, allergic, viral and genetic aetiological causes. Successful diagnosis relies on the use of oesophagogastroduodenoscopy, barium swallow and oesophageal manometry to characterise the severity of the disease and to rule out underlying malignancy. Although no treatment can reverse the degenerative process, therapeutic strategies including lifestyle modification, medication, endoscopic and operative intervention can help to reduce symptoms. This article reviews the latest methods used to investigate and manage achalasia.

Detection of cytokine storm in patients with achalasia using ELISA

Esophageal achalasia is characterized by abnormal peristaltic movements of the esophageal body and impaired relaxation of the lower esophageal sphincter (LES). However, its etiology remains unknown. In our previous study, it was shown that in the LES of patients with achalasia, hsv1-miR-H1 was overexpressed, ATG16L1 expression was downregulated and interleukin (IL)-1β levels were upregulated. However, systemic features were not evaluated. Herein, the plasma cytokine levels in patients with achalasia were determined. Plasma was collected from patients at Nagasaki University Hospital between February 2013 and March 2016, both before and after peroral endoscopic myotomy (POEM). Cytokine analysis was performed using plasma collected from 10 healthy individuals (control group) and 12 patients with achalasia using the Bio-Plex Pro™ Human Cytokine 27-plex assay kit. The levels of IL-17, IL-1β, C-C motif chemokine ligand 2, IL-4, IL-5, IL-1ra, IL-7, IL-12, interferon-γ, IL-2, fibroblast growth factor-2, colony-stimulating factor (CSF)2 and CSF3 were significantly higher in patients with achalasia compared with the control subjects. However, the levels did not differ between plasma samples collected before and after POEM. Thus, the occurrence of a cytokine storm was confirmed in the patients with achalasia.