ReBiA-Robotic Enabled Biological Automation: 3D Epithelial Tissue Production.

The Food and Drug Administration's recent decision to eliminate mandatory animal testing for drug approval marks a significant shift to alternative methods. Similarly, the European Parliament is advocating for a faster transition, reflecting public preference for animal-free research practices. In vitro tissue models are increasingly recognized as valuable tools for regulatory assessments before clinical trials, in line with the 3R principles (Replace, Reduce, Refine).

Hepatic stellate cells in zone 1 engage in capillarization rather than myofibroblast formation in murine liver fibrosis.

The combination of lineage tracing and immunohistochemistry has helped to identify subpopulations and fate of hepatic stellate cells (HSC) in murine liver. HSC are sinusoidal pericytes that act as myofibroblast precursors after liver injury. Single cell RNA sequencing approaches have recently helped to differentiate central and portal HSC.

Biomimetic Connection of Transcutaneous Implants with Skin.

Bacterial infection is a crucial complication in implant restoration, in particular in permanent skin-penetrating implants. Therein, the resulting gap between transcutaneous implant and skin represents a permanent infection risk, limiting the field of application and the duration of application. To overcome this limitation, a tight physiological connection is required to achieve a biological and mechanical welding for a long-term stable closure including self-healing probabilities.

NO-sensitive guanylyl cyclase discriminates pericyte-derived interstitial from intra-alveolar myofibroblasts in murine pulmonary fibrosis.

Background: The origin of αSMA-positive myofibroblasts, key players within organ fibrosis, is still not fully elucidated. Pericytes have been discussed as myofibroblast progenitors in several organs including the lung.

Methods: Using tamoxifen-inducible PDGFRβ-tdTomato mice (PDGFRβ-CreER; R26tdTomato) lineage of lung pericytes was traced.

Gastrointestinal dysfunction in autism displayed by altered motility and achalasia in mice.

Gastrointestinal dysfunctions in individuals with autism spectrum disorder are poorly understood, although they are common among this group of patients. haploinsufficiency is characterized by autistic behavior, language impairment, and intellectual disability, but feeding difficulties and gastrointestinal problems have also been reported. Whether these are primary impairments, the result of altered eating behavior, or side effects of psychotropic medication remains unclear.

NO-GC in cells 'off the beaten track'.

Nitric oxide-sensitive guanylyl cyclase (NO-GC) has been shown to regulate a plethora of different functions in the body. These include, among many others, the fine-tuning of vascular tone, platelet reactivity and gastrointestinal motility. Evidence for the participation of NO-GC in these functions has been obtained from various species including humans, rodents, as well as insects.

Cardioprotection by ischemic postconditioning and cyclic guanosine monophosphate-elevating agents involves cardiomyocyte nitric oxide-sensitive guanylyl cyclase.

Aims: It has been suggested that the nitric oxide-sensitive guanylyl cyclase (NO-GC)/cyclic guanosine monophosphate (cGMP)-dependent signalling pathway affords protection against cardiac damage during acute myocardial infarction (AMI). It is, however, not clear whether the NO-GC/cGMP system confers its favourable effects through a mechanism located in cardiomyocytes (CMs). The aim of this study was to evaluate the infarct-limiting effects of the endogenous NO-GC in CMs in vivo.

The IgCAM CLMP regulates expression of Connexin43 and Connexin45 in intestinal and ureteral smooth muscle contraction in mice.

CAR-like membrane protein (CLMP), an immunoglobulin cell adhesion molecule (IgCAM), has been implicated in congenital short-bowel syndrome in humans, a condition with high mortality for which there is currently no cure. We therefore studied the function of CLMP in a -deficient mouse model. Although we found that the levels of mRNAs encoding Connexin43 or Connexin45 were not or were only marginally affected, respectively, by deficiency, the absence of CLMP caused a severe reduction of both proteins in smooth muscle cells of the intestine and of Connexin43 in the ureter.

Phosphodiesterase 3A expression and activity in the murine vasculature is influenced by NO-sensitive guanylyl cyclase.

Phosphodiesterase 3 (PDE3) exists in two isoforms (PDE3A and PDE3B) and is known to act as cGMP-inhibited cAMP-degrading PDE. Therefore, PDE3 may likely be involved in the interaction between the two second messenger pathways. NO-sensitive guanylyl cyclase (NO-GC) is the most important cytosolic generator of cGMP.

Optical control of a receptor-linked guanylyl cyclase using a photoswitchable peptidic hormone.

The optical control over biological function with small photoswitchable molecules has gathered significant attention in the last decade. Herein, we describe the design and synthesis of a small library of photoswitchable peptidomimetics based upon human atrial natriuretic peptide (ANP), in which the photochromic amino acid [3-(3-aminomethyl)phenylazo]phenylacetic acid (AMPP) is incorporated into the peptide backbone. The endogeneous hormone ANP signals the natriuretic peptide receptor A (NPR-A) through raising intracellular cGMP concentrations, and is involved in blood pressure regulation and sodium homeostasis, as well as lipid metabolism and pancreatic function.

Integrative Control of Gastrointestinal Motility by Nitric Oxide.

In the gastrointestinal (GI) tract, nitric oxide (NO) has been shown over the last 25 years to exert a prominent function as inhibitory neurotransmitter. Apart from the regulation of secretion and resorption, NO from nitrergic neurons has been demonstrated to be crucial for GI smooth muscle relaxation and motility. In fact, several human diseases such as achalasia, gastroparesis, slow transit constipation or Hirschsprung's disease may involve dysfunctional nitrergic signaling.

Soluble guanylate cyclase as an alternative target for bronchodilator therapy in asthma.

Asthma is defined by airway inflammation and hyperresponsiveness, and contributes to morbidity and mortality worldwide. Although bronchodilation is a cornerstone of treatment, current bronchodilators become ineffective with worsening asthma severity. We investigated an alternative pathway that involves activating the airway smooth muscle enzyme, soluble guanylate cyclase (sGC).

Nitrergic signalling via interstitial cells of Cajal regulates motor activity in murine colon.

In the enteric nervous systems, NO is released from nitrergic neurons as a major inhibitory neurotransmitter. NO acts via NO-sensitive guanylyl cyclase (NO-GC), which is found in different gastrointestinal (GI) cell types including smooth muscle cells (SMCs) and interstitial cells of Cajal (ICC). The precise mechanism of nitrergic signalling through these two cell types to regulate colonic spontaneous contractions is not fully understood yet.

Cell-specific impact of nitric oxide-dependent guanylyl cyclase on arteriogenesis and angiogenesis in mice.

Nitric oxide (NO) acts as essential regulator of vasculogenesis and angiogenesis and is critical for arteriogenesis. Whether NO's effects in vivo are mediated through NO-sensitive guanylyl cyclase (NO-GC) and thus by cGMP-dependent mechanisms has been only poorly addressed. Mice lacking NO-GC globally or specifically in smooth muscle cells (SMC) or endothelial cells (EC) were subjected to two established models for arteriogenesis and angiogenesis, namely hindlimb ischemia and oxygen-induced retinopathy.

Dominant role of interstitial cells of Cajal in nitrergic relaxation of murine lower oesophageal sphincter.

Oesophageal achalasia is a disease known to result from reduced relaxation of the lower oesophageal sphincter (LES). Nitric oxide (NO) is one of the main inhibitory transmitters. NO-sensitive guanylyl cyclase (NO-GC) acts as the key target of NO and, by the generation of cGMP, mediates nitrergic relaxation in the LES.

Soluble guanylate cyclase is required for systemic vasodilation but not positive inotropy induced by nitroxyl in the mouse.

Nitroxyl (HNO), the reduced and protonated form of nitric oxide (NO·), confers unique physiological effects including vasorelaxation and enhanced cardiac contractility. These features have spawned current pharmaceutical development of HNO donors as heart failure therapeutics. HNO interacts with selective redox sensitive cysteines to effect signaling but is also proposed to activate soluble guanylate cyclase (sGC) in vitro to induce vasodilation and potentially enhance contractility.

Interstitial cells of Cajal mediate nitrergic inhibitory neurotransmission in the murine gastrointestinal tract.

Nitric oxide (NO) is a major inhibitory neurotransmitter in the gastrointestinal (GI) tract. Its main effector, NO-sensitive guanylyl cyclase (NO-GC), is expressed in several GI cell types, including smooth muscle cells (SMC), interstitial cells of Cajal (ICC), and fibroblast-like cells. Up to date, the interplay between neurons and these cells to initiate a nitrergic inhibitory junction potential (IJP) is unclear.

Correlation of cellular expression with function of NO-sensitive guanylyl cyclase in the murine lower urinary tract.

The action of nitric oxide (NO) to stimulate NO-sensitive guanylyl cyclase (NO-GC), followed by production of cGMP, and eventually to cause smooth muscle relaxation is well known. In the lower urinary tract (LUT), in contrast to the cardiovascular system and the gastrointestinal tract, specific localization in combination with function of NO-GC has not been investigated to date. Consequently, little is known about the mechanisms regulating relaxation of the lower urinary tract in general and the role of NO-GC-expressing cells in particular.

Lack of effect of ODQ does not exclude cGMP signalling via NO-sensitive guanylyl cyclase.

Background And Purpose: Nitric oxide (NO) is known to activate NO-sensitive guanylyl cyclase (NO-GC) and to elicit cGMP production. However, NO has also been proposed to induce cGMP-independent effects. It is accepted practice to use specific NO-GC inhibitors, such as ODQ or NS2028, to assess cGMP-dependent NO effects.

Radioimmunoassay for the quantification of cGMP levels in cells and tissues.

Radioimmunoassay is an established method to determine the amount of a specific substance in a given cell or tissue sample. Commercially available RIA or Elisa are very cost intensive. Here, we describe the generation of radioactive cGMP tracer and the quantification of cGMP.

Cell-specific deletion of nitric oxide-sensitive guanylyl cyclase reveals a dual pathway for nitrergic neuromuscular transmission in the murine fundus.

Background & Aims: It is not clear how nitric oxide (NO) released from enteric neurons relaxes gastrointestinal (GI) smooth muscle. In analogy to the vascular system, NO might directly induce relaxation of smooth muscle cells (SMCs) by acting on its receptor, NO-sensitive guanylyl cyclase (NO-GC). Alternatively, intermediate cells, such as the interstitial cells of Cajal (ICCs), might detect nitrergic signals to indirectly regulate smooth muscle tone, and thereby regulate the motor function of the GI tract.

Preserved fertility despite erectile dysfunction in mice lacking the nitric oxide receptor.

Nitric oxide (NO) and cGMP have been shown to be important mediators of penile erection. Erectile dysfunction may result from reduced or non-functional signal transduction within this cascade. There is, however, some inconsistency in the available data as mice lacking NO synthases (endothelial and neuronal nitric oxide synthase, or both) appear to be fertile whereas mice deficient in cGMP-dependent protein kinase I (PKGI) suffer from erectile dysfunction.