Reducing risks for infant mortality in the Midlands, UK: a qualitative study identifying areas for improvement in the delivery of key public health messages in the perinatal period.

BACKGROUND: The Midlands has amongst the highest rates of neonatal and infant mortality in the UK. A public health parent education and empowerment programme, aimed at reducing key risks associated with this mortality was established and evaluated in the region. This was undertaken in an attempt to identify areas for optimal delivery of the public health messages around reducing risks for neonatal and infant mortality. METHOD: Qualitatively assessment, using the software package Dedoose®, was undertaken. This involved analysis of reflections by the programme trainers, after the delivery of their training sessions to parents, families and carers, between 01 January and 31 December 2021. These were intended to capture insights from the trainers on parent, family, carer and staff perspectives, perceptions/misperceptions around reducing risks for infant mortality. Potential areas for improvement in delivery of the programme were identified from this analysis. RESULTS: A total of 323 programmes, comprising 524 parents, family members and carers were offered the programme. Analysis of 167 reflections around these interactions and those of staff (n = 29) are reported. The programme was positively received across parents, families, carers and staff. Four overall themes were identified: (a) reach and inclusion, (b) knowledge, (c) practical and emotional support and (d) challenges for delivery of the programme. Recommendations for improved delivery of the programme were identified, based on qualitative analysis. CONCLUSION: This novel approach to empowerment and education around neonatal public health messaging is a valuable tool for parents, families, carers and staff in the Midlands. Key practical recommendations for enhancing delivery of these critical public health messages were identified from this qualitative research. These are likely to be of value in other parts of the UK and globally.

Differential effects of SOCS2 on neuronal differentiation and morphology.

Neuronal differentiation of neural progenitor cells is regulated by a variety of growth and transcription factors, that not only regulate cell fate of the progenitor cells but that can also regulate neuronal morphology. Suppressor of cytokine signaling-2 (SOCS2) is an intracellular regulator of Growth Hormone (GH) signaling that is expressed in neural stem cells and neurons during development and is required to overcome the inhibitory effects of GH on neuronal differentiation. SOCS2 also promotes neurite outgrowth, however, whether the mechanism by which SOCS2 regulates neuronal differentiation and neurite outgrowth is the same is not clear. Furthermore, whether the over-expression of SOCS2 has physiological in addition to morphological effects is unknown. To address these questions, we differentiated adult neural progenitor cells derived from wildtype C57BL/6 or SOCS2 over-expressing transgenic mice (SOCS2Tg) in the presence or absence of GH and determined effects on neuronal differentiation and morphology. Compared to wildtype cells, differentiation of SOCS2Tg neurospheres resulted in increased neurogenesis, which was not inhibited by GH. The neurons derived from these cells appeared more complex, with increased neurite outgrowth and number. GH did not, however, have any effect on neurite outgrowth of wildtype or SOCS2Tg neurons. Furthermore, basic electrophysiological analysis of wildtype and SOCS2Tg neurons derived from the neurospheres showed that they were both of an immature electrophysiological neuronal phenotype, indicating that although SOCS2 expression can regulate neuronal morphology, it appears to have little effect on neuronal ion channel expression.

SOCS2 induces neurite outgrowth by regulation of epidermal growth factor receptor activation.

Suppressor of cytokine signaling (SOCS) 2 is a negative regulator of growth hormone (GH) signaling that regulates body growth postnatally and neuronal differentiation during development. SOCS2 binds to the GH receptor and inhibits GH signaling, including attenuation of STAT5 activation. Here we describe a new function and mechanism of action for SOCS2. Overexpression of SOCS2 in central nervous system neurons promoted neurite outgrowth, and in PC12 cells, neurite outgrowth was induced under nondifferentiating conditions, leading to inhibition of the neurite-inhibitory GTPase Rho and activation of the neurite-promoting GTPase Rac1. Addition of the epidermal growth factor receptor (EGFR) inhibitors PP3 or AG490 or the Src kinase inhibitor PP2 blocked the SOCS2-induced neurite outgrowth. The overexpressed SOCS2 bound to the EGFR, which was constitutively phosphorylated at Tyr845, the Src binding site. Overexpression of the phosphatase SHP-2 reduced the constitutive EGFR phosphorylation and subsequent neurite outgrowth. SOCS2 expression also resulted in a modest 30% decrease in phosphorylation of STAT5b at Tyr699, which is the primary site on STAT5 phosphorylated by GH; however, total tyrosine phosphorylation of STAT5 was decreased by 75-80% under basal and epidermal growth factor-stimulated conditions. Our findings suggest that SOCS2 regulates EGFR phosphorylation, leading to regulation of neurite outgrowth through a novel pathway that is distinct from GH.

Intracellular domain of brain endothelial intercellular adhesion molecule-1 is essential for T lymphocyte-mediated signaling and migration.

To examine the role of the ICAM-1 C-terminal domain in transendothelial T lymphocyte migration and ICAM-1-mediated signal transduction, mutant human (h)ICAM-1 molecules were expressed in rat brain microvascular endothelial cells. The expression of wild-type hICAM-1 resulted in a significant increase over basal levels in both adhesion and transendothelial migration of T lymphocytes. Endothelial cells (EC) expressing ICAM-1 in which the tyrosine residue at codon 512 was substituted with phenylalanine (hICAM-1(Y512F)) also exhibited increased lymphocyte migration, albeit less than that with wild-type hICAM-1. Conversely, the expression of truncated hICAM-1 proteins, in which either the intracellular domain was deleted (hICAM-1DeltaC) or both the intracellular and transmembrane domains were deleted through construction of a GPI anchor (GPI-hICAM-1), did not result in an increase in lymphocyte adhesion, and their ability to increase transendothelial migration was attenuated. Truncated hICAM-1 proteins were also unable to induce ICAM-1-mediated Rho GTPase activation. EC treated with cell-permeant penetratin-ICAM-1 peptides comprising human or rat ICAM-1 intracellular domain sequences inhibited transendothelial lymphocyte migration, but not adhesion. Peptides containing a phosphotyrosine residue were equipotent in inhibiting lymphocyte migration. These data demonstrate that the intracellular domain of ICAM-1 is essential for transendothelial migration of lymphocytes, and that peptidomimetics of the ICAM-1 intracellular domain can also inhibit this process. Such competitive inhibition of transendothelial lymphocyte migration in the absence of an affect on adhesion further implicates ICAM-1-mediated signaling events in the facilitation of T lymphocyte migration across brain EC. Thus, agents that mimic the ICAM-1 intracellular domain may be attractive targets for novel anti-inflammatory therapeutics.

Lovastatin inhibits brain endothelial cell Rho-mediated lymphocyte migration and attenuates experimental autoimmune encephalomyelitis.

Neuroinflammatory diseases, such as multiple sclerosis (MS), result from aberrant leukocyte traffic into the central nervous system (CNS). To breach the specialized blood-brain barrier, activated leukocytes interact with CNS endothelial cells (EC) and activate a CD54-mediated signaling pathway controlling the Rho GTPase. To function correctly Rho requires posttranslational prenylation, and this can be inhibited by depleting the supply of isoprenoids through inhibition of the cholesterol synthesis pathway with 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase) inhibitors (statins). Here we show that treatment of brain EC in vitro with lovastatin inhibits Rho-mediated transendothelial T cell migration. This effect can be reversed by supplementation with mevalonolactone, the downstream product of HMG-CoA reductase, or by ectopic expression of myristoylated Rho, which remains active in the absence of prenylation. In a relapsing-remitting mouse model of MS, lovastatin treatment inhibited leukocyte migration into the CNS and significantly attenuated the development of both acute and relapsing clinical disease. These studies demonstrate that the indirect pharmacological inhibition of Rho proteins in brain EC by statins can inhibit a key stage in the pathogenesis of neuroinflammation, namely leukocyte migration across the blood-brain barrier. These studies demonstrate a novel effect of statins in modulating the immune response in neuroinflammtory diseases and may provide additional rationale for their use in the treatment of MS.

Inhibition of Rho GTPases with protein prenyltransferase inhibitors prevents leukocyte recruitment to the central nervous system and attenuates clinical signs of disease in an animal model of multiple sclerosis.

The ICAM-1-mediated brain endothelial cell (EC)-signaling pathway induced by adherent lymphocytes is a central element in facilitating lymphocyte migration through the tight endothelial barrier of the brain. Rho proteins, which must undergo posttranslational prenylation to be functionally active, have been shown to be an essential component of this signaling cascade. In this study, we have evaluated the effect of inhibiting protein prenylation in brain ECs on their ability to support T lymphocyte migration. ECs treated in vitro with protein prenylation inhibitors resulted in a significant reduction in transendothelial T lymphocyte migration. To determine the therapeutic potential of this approach, an animal model of multiple sclerosis, experimental autoimmune encephalomyelitis, was induced in Biozzi ABH mice. Animals treated before disease onset with protein prenylation inhibitors exhibited a dramatic and significant reduction in both leukocyte infiltration into the CNS and clinical presentation of disease compared with untreated animals. These studies demonstrate, for the first time, the potential for pharmacologically targeting CNS EC signaling responses, and particularly endothelial Rho proteins, as a means of attenuating leukocyte recruitment to the CNS.