Tuakana-teina peer education programme to help Maori elders enhance wellbeing and social connectedness.

BACKGROUND: There are significant inequities between Maori (Indigenous people) and non-Maori in ageing outcomes. This study used a strengths-based approach based on the key cultural concept of mana motuhake (autonomy and self-actualisation) to develop a tuakana-teina (literally older sibling-younger sibling) peer education programme to assist kaumatua (elders) in addressing health and social needs. The purpose of this study was to test the impact on those receiving the programme. Three aims identify the impact on outcomes, resources received and the cost effectiveness of the programme. METHODS: Five Kaupapa Maori (research and services guided by Maori worldviews) iwi (tribe) and community providers implemented the project using a partnership approach. Tuakana (peer educators) had up to six conversations each with up to six teina (peer learners) and shared information related to social and health services. A pre- and post-test, clustered staggered design was the research design. Participants completed a baseline and post-programme assessment of health and mana motuhake measures consistent with Maori worldviews. Open-ended questions on the assessments, five focus groups, and four individual interviews were used for qualitative evaluation. FINDINGS: A total of 113 kaumatua were recruited, and 86 completed the programme. The analysis revealed improvements in health-related quality of life, needing more help with daily tasks, life satisfaction, paying bills and housing problems. Qualitative results supported impacts of the programme on mana motuhake and hauora (holistic health) through providing intangible and tangible resources. Cost-effectiveness analysis showed that the intervention is cost effective, with a cost per QALY of less than the conventional threshold of three times GDP per capita. CONCLUSIONS: A culturally-resonant, strengths-based programme developed through a participatory approach can significantly improve health and social outcomes in a cost-effective way. TRIAL REGISTRY: Clinical trial registry: Trial registration: (ACTRN12620000316909). Prospectively registered 06/03/2020, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=379302&isClinicalTrial=False .

Enhancing health outcomes for Maori elders through an intergenerational cultural exchange and physical activity programme: a cross-sectional baseline study.

Background: The study offers baseline data for a strengths-based approach emphasizing intergenerational cultural knowledge exchange and physical activity developed through a partnership with kaumatua (Maori elders) and kaumatua service providers. The study aims to identify the baseline characteristics, along with correlates of five key outcomes. Methods: The study design is a cross-sectional survey. A total of 75 kaumatua from six providers completed two physical functioning tests and a survey that included dependent variables based in a holistic model of health: health-related quality of life (HRQOL), self-rated health, spirituality, life satisfaction, and loneliness. Results: The findings indicate that there was good reliability and moderate scores on most variables. Specific correlates included the following: (a) HRQOL: emotional support (ß = 0.31), and frequent interaction with a co-participant (ß = 0.25); (b) self-rated health: frequency of moderate exercise (ß = 0.32) and sense of purpose (ß = 0.27); (c) spirituality: sense of purpose (ß = 0.46), not needing additional help with daily tasks (ß = 0.28), and level of confidence with cultural practices (ß = 0.20); (d) life satisfaction: sense of purpose (ß = 0.57), frequency of interaction with a co-participant (ß = -0.30), emotional support (ß = 0.25), and quality of relationship with a co-participant (ß = 0.16); and (e) lower loneliness: emotional support (ß = 0.27), enjoyment interacting with a co-participant (ß = 0.25), sense of purpose (ß = 0.24), not needing additional help with daily tasks (ß = 0.28), and frequency of moderate exercise (ß = 0.18). Conclusion: This study provides the baseline scores and correlates of important social and health outcomes for the He Huarahi Tautoko (Avenue of Support) programme, a strengths-based approach for enhancing cultural connection and physical activity.

Enhancing Well-Being and Social Connectedness for Maori Elders Through a Peer Education (Tuakana-Teina) Programme: A Cross-Sectional Baseline Study.

Background: Maori kaumatua (elders) face stark health and social inequities compared to non-Maori New Zealanders. The tuakana-teina (older sibling-younger sibling) peer education programme is a strengths-based approach to enhance well-being and social connectedness. The purpose of this study is to present the baseline data from this programme and identify correlates of well-being outcomes. Method: Participants included 128 kaumatua who completed a self-report survey about health-related quality of life, spirituality, social connection and loneliness, life satisfaction, cultural identity and connection, elder abuse, health service utilisation and demographics. Findings: Multiple regression models illustrated the following correlates of outcomes: (a) self-rated health: needing more help with daily tasks (ß = -0.36) and housing problems (ß = -0.17); (b) health-related quality of life: needing more help with daily tasks (ß = -0.31), housing problems (ß = -0.21), and perceived autonomy (ß = 0.19); (c) spiritual well-being: understanding of tikanga (cultural protocols) (ß = 0.32) and perceived autonomy (ß = 0.23); (d) life satisfaction: social support (ß = 0.23), sense of purpose (ß = 0.23), cultural identity (ß = 0.24), trouble paying bills (ß = -0.16), and housing problems (ß = -0.16); (e) loneliness: elder abuse (ß = 0.27), social support (ß = -0.21), and missing pleasure of being with whanau (extended family) (ß = 0.19). Conclusions: Key correlates for outcomes centred on social support, housing problems, cultural connection and perceived autonomy. These correlates are largely addressed through the programme where tuakana/peer educators provide support and links to social and health services to teina/peer recipients in need. This study illustrates needs and challenges for kaumatua, whilst the larger programme represents a strengths-based and culturally-centred approach to address health issues related to ageing in an Indigenous population.

Kaumatua Mana Motuhake Poi: a study protocol for enhancing wellbeing, social connectedness and cultural identity for Maori elders.

BACKGROUND: The Aotearoa New Zealand population is ageing accompanied by health and social challenges including significant inequities that exist between Maori and non-Maori around poor ageing and health. Although historically kaumatua (elder Maori) faced a dominant society that failed to realise their full potential as they age, Maori culture has remained steadfast in upholding elders as cultural/community anchors. Yet, many of today's kaumatua have experienced 'cultural dissonance' as the result of a hegemonic dominant culture subjugating an Indigenous culture, leading to generations of Indigenous peoples compelled or forced to dissociate with their culture. The present research project, Kaumatua Mana Motuhake Poi (KMMP) comprises two interrelated projects that foreground dimensions of wellbeing within a holistic Te Ao Maori (Maori epistemology) view of wellbeing. Project 1 involves a tuakana-teina/peer educator model approach focused on increasing service access and utilisation to support kaumatua with the greatest health and social needs. Project 2 focuses on physical activity and cultural knowledge exchange (including te reo Maori--Maori language) through intergenerational models of learning. METHODS: Both projects have a consistent research design and common set of methods that coalesce around the emphasis on kaupapa kaumatua; research projects led by kaumatua and kaumatua providers that advance better life outcomes for kaumatua and their communities. The research design for each project is a mixed-methods, pre-test and two post-test, staggered design with 2-3 providers receiving the approach first and then 2-3 receiving it on a delayed basis. A pre-test (baseline) of all participants will be completed. The approach will then be implemented with the first providers. There will then be a follow-up data collection for all participants (post-test 1). The second providers will then implement the approach, which will be followed by a final data collection for all participants (post-test 2). DISCUSSION: Two specific outcomes are anticipated from this research; firstly, it is hoped that the research methodology provides a framework for how government agencies, researchers and relevant sector stakeholders can work with Maori communities. Secondly, the two individual projects will each produce a tangible approach that, it is anticipated, will be cost effective in enhancing kaumatua hauora and mana motuhake. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry ( ACTRN12620000316909 ). Registered 6 March 2020.

The fragile X mutation impairs homeostatic plasticity in human neurons by blocking synaptic retinoic acid signaling.

Fragile X syndrome (FXS) is an X chromosome-linked disease leading to severe intellectual disabilities. FXS is caused by inactivation of the fragile X mental retardation 1 (FMR1) gene, but how FMR1 inactivation induces FXS remains unclear. Using human neurons generated from control and FXS patient-derived induced pluripotent stem (iPS) cells or from embryonic stem cells carrying conditional FMR1 mutations, we show here that loss of FMR1 function specifically abolished homeostatic synaptic plasticity without affecting basal synaptic transmission. We demonstrated that, in human neurons, homeostatic plasticity induced by synaptic silencing was mediated by retinoic acid, which regulated both excitatory and inhibitory synaptic strength. FMR1 inactivation impaired homeostatic plasticity by blocking retinoic acid-mediated regulation of synaptic strength. Repairing the genetic mutation in the FMR1 gene in an FXS patient cell line restored fragile X mental retardation protein (FMRP) expression and fully rescued synaptic retinoic acid signaling. Thus, our study reveals a robust functional impairment caused by FMR1 mutations that might contribute to neuronal dysfunction in FXS. In addition, our results suggest that FXS patient iPS cell-derived neurons might be useful for studying the mechanisms mediating functional abnormalities in FXS.

Human Neuropsychiatric Disease Modeling using Conditional Deletion Reveals Synaptic Transmission Defects Caused by Heterozygous Mutations in NRXN1.

Heterozygous mutations of the NRXN1 gene, which encodes the presynaptic cell-adhesion molecule neurexin-1, were repeatedly associated with autism and schizophrenia. However, diverse clinical presentations of NRXN1 mutations in patients raise the question of whether heterozygous NRXN1 mutations alone directly impair synaptic function. To address this question under conditions that precisely control for genetic background, we generated human ESCs with different heterozygous conditional NRXN1 mutations and analyzed two different types of isogenic control and NRXN1 mutant neurons derived from these ESCs. Both heterozygous NRXN1 mutations selectively impaired neurotransmitter release in human neurons without changing neuronal differentiation or synapse formation. Moreover, both NRXN1 mutations increased the levels of CASK, a critical synaptic scaffolding protein that binds to neurexin-1. Our results show that, unexpectedly, heterozygous inactivation of NRXN1 directly impairs synaptic function in human neurons, and they illustrate the value of this conditional deletion approach for studying the functional effects of disease-associated mutations.

Retinoic Acid and LTP Recruit Postsynaptic AMPA Receptors Using Distinct SNARE-Dependent Mechanisms.

Retinoic acid (RA)-dependent homeostatic plasticity and NMDA receptor-dependent long-term potentiation (LTP), a form of Hebbian plasticity, both enhance synaptic strength by increasing the abundance of postsynaptic AMPA receptors (AMPARs). However, it is unclear whether the molecular mechanisms mediating AMPAR trafficking during homeostatic and Hebbian plasticity differ, and it is unknown how RA signaling impacts Hebbian plasticity. Here, we show that RA increases postsynaptic AMPAR abundance using an activity-dependent mechanism that requires a unique SNARE (soluble NSF-attachment protein receptor)-dependent fusion machinery different from that mediating LTP. Specifically, RA-induced AMPAR trafficking did not involve complexin, which activates SNARE complexes containing syntaxin-1 or -3, but not complexes containing syntaxin-4, whereas LTP required complexin. Moreover, RA-induced AMPAR trafficking utilized the Q-SNARE syntaxin-4, whereas LTP utilized syntaxin-3; both additionally required the Q-SNARE SNAP-47 and the R-SNARE synatobrevin-2. Finally, acute RA treatment blocked subsequent LTP expression, probably by increasing AMPAR trafficking. Thus, RA-induced homeostatic plasticity involves a novel, activity-dependent postsynaptic AMPAR-trafficking pathway mediated by a unique SNARE-dependent fusion machinery.

Rapid single-step induction of functional neurons from human pluripotent stem cells.

Available methods for differentiating human embryonic stem cells (ESCs) and induced pluripotent cells (iPSCs) into neurons are often cumbersome, slow, and variable. Alternatively, human fibroblasts can be directly converted into induced neuronal (iN) cells. However, with present techniques conversion is inefficient, synapse formation is limited, and only small amounts of neurons can be generated. Here, we show that human ESCs and iPSCs can be converted into functional iN cells with nearly 100% yield and purity in less than 2 weeks by forced expression of a single transcription factor. The resulting ES-iN or iPS-iN cells exhibit quantitatively reproducible properties independent of the cell line of origin, form mature pre- and postsynaptic specializations, and integrate into existing synaptic networks when transplanted into mouse brain. As illustrated by selected examples, our approach enables large-scale studies of human neurons for questions such as analyses of human diseases, examination of human-specific genes, and drug screening.

LTP requires a unique postsynaptic SNARE fusion machinery.

Membrane fusion during exocytosis is mediated by assemblies of SNARE (soluble NSF-attachment protein receptor) and SM (Sec1/Munc18-like) proteins. The SNARE/SM proteins involved in vesicle fusion during neurotransmitter release are well understood, whereas little is known about the protein machinery that mediates activity-dependent AMPA receptor (AMPAR) exocytosis during long-term potentiation (LTP). Using direct measurements of LTP in acute hippocampal slices and an in vitro LTP model of stimulated AMPAR exocytosis, we demonstrate that the Q-SNARE proteins syntaxin-3 and SNAP-47 are required for regulated AMPAR exocytosis during LTP but not for constitutive basal AMPAR exocytosis. In contrast, the R-SNARE protein synaptobrevin-2/VAMP2 contributes to both regulated and constitutive AMPAR exocytosis. Both the central complexin-binding and the N-terminal Munc18-binding sites of syntaxin-3 are essential for its postsynaptic role in LTP. Thus, postsynaptic exocytosis of AMPARs during LTP is mediated by a unique fusion machinery that is distinct from that used during presynaptic neurotransmitter release.

Syntaxin-1 N-peptide and Habc-domain perform distinct essential functions in synaptic vesicle fusion.

Among SNARE proteins mediating synaptic vesicle fusion, syntaxin-1 uniquely includes an N-terminal peptide ('N-peptide') that binds to Munc18-1, and a large, conserved H(abc)-domain that also binds to Munc18-1. Previous in vitro studies suggested that the syntaxin-1 N-peptide is functionally important, whereas the syntaxin-1 H(abc)-domain is not, but limited information is available about the in vivo functions of these syntaxin-1 domains. Using rescue experiments in cultured syntaxin-deficient neurons, we now show that the N-peptide and the H(abc)-domain of syntaxin-1 perform distinct and independent roles in synaptic vesicle fusion. Specifically, we found that the N-peptide is essential for vesicle fusion as such, whereas the H(abc)-domain regulates this fusion, in part by forming the closed syntaxin-1 conformation. Moreover, we observed that deletion of the H(abc)-domain but not deletion of the N-peptide caused a loss of Munc18-1 which results in a decrease in the readily releasable pool of vesicles at a synapse, suggesting that Munc18 binding to the H(abc)-domain stabilizes Munc18-1. Thus, the N-terminal syntaxin-1 domains mediate different functions in synaptic vesicle fusion, probably via formation of distinct Munc18/SNARE-protein complexes.

CSPα knockout causes neurodegeneration by impairing SNAP-25 function.

At a synapse, the synaptic vesicle protein cysteine-string protein-α (CSPα) functions as a co-chaperone for the SNARE protein SNAP-25. Knockout (KO) of CSPα causes fulminant neurodegeneration that is rescued by α-synuclein overexpression. The CSPα KO decreases SNAP-25 levels and impairs SNARE-complex assembly; only the latter but not the former is reversed by α-synuclein. Thus, the question arises whether the CSPα KO phenotype is due to decreased SNAP-25 function that then causes neurodegeneration, or due to the dysfunction of multiple as-yet uncharacterized CSPα targets. Here, we demonstrate that decreasing SNAP-25 levels in CSPα KO mice by either KO or knockdown of SNAP-25 aggravated their phenotype. Conversely, increasing SNAP-25 levels by overexpression rescued their phenotype. Inactive SNAP-25 mutants were unable to rescue, showing that the rescue was specific. Under all conditions, the neurodegenerative phenotype precisely correlated with SNARE-complex assembly, indicating that impaired SNARE-complex assembly due to decreased SNAP-25 levels is the ultimate correlate of neurodegeneration. Our findings suggest that the neurodegeneration in CSPα KO mice is primarily produced by defective SNAP-25 function, which causes neurodegeneration by impairing SNARE-complex assembly.

Methylation-mediated downregulation of the B-cell translocation gene 3 (BTG3) in breast cancer cells.

The incidence of solid tumors is low in individuals with Down syndrome (trisomy 21), suggesting the presence of one or more tumor suppressor genes on chromosome 21. Consistent with this finding, previous work has demonstrated frequent loss of heterozygosity (LOH) of a small (< 5 Mb) region of chromosome 21, particularly in breast cancer, indicating that a tumor suppressor gene(s) may be located in this region. We investigated the expression of BTG3, a gene in the LOH region on chromosome 21, in breast cancer cell lines. BTG3 has been shown to be a negative regulator of SRC tyrosine kinase, and BTG3 is a target of p53 and inhibits the activity of the E2F1 transcription factor. Here we demonstrate that in a wide variety of human breast cancer cell lines, BTG3 expression is markedly reduced in the absence of detectable mutations in the BTG3 promoter and coding region. In these cell lines, the promoter region of the BTG3 gene is hypermethylated when compared to normal breast cell lines. BTG3 gene expression can be restored by treatment with 5'-aza-deoxycytidine, an inhibitor of DNA methylation. These data support the hypothesis that BTG3 may act to suppress tumorigenesis and that hypermethylation is an important mechanism for inactivation of BTG3 and perhaps other tumor suppressor genes. The findings are consistent with a role for an additional copy of BTG3 in the reduced incidence of breast cancer in individuals with Down syndrome.

Directed differentiation of ventral spinal progenitors and motor neurons from human embryonic stem cells by small molecules.

Specification of distinct cell types from human embryonic stem cells (hESCs) is key to the potential application of these naïve pluripotent cells in regenerative medicine. Determination of the nontarget differentiated populations, which is lacking in the field, is also crucial. Here, we show an efficient differentiation of motor neurons ( approximately 50%) by a simple sequential application of retinoid acid and sonic hedgehog (SHH) in a chemically defined suspension culture. We also discovered that purmorphamine, a small molecule that activates the SHH pathway, could replace SHH for the generation of motor neurons. Immunocytochemical characterization indicated that cells differentiated from hESCs were nearly completely restricted to the ventral spinal progenitor fate (NKX2.2+, Irx3+, and Pax7-), with the exception of motor neurons (HB9+) and their progenitors (Olig2+). Thus, the directed neural differentiation system with small molecules, even without further purification, will facilitate basic and translational studies using human motoneurons at a minimal cost.

Transgenes delivered by lentiviral vector are suppressed in human embryonic stem cells in a promoter-dependent manner.

Lentiviruses have been increasingly used for genetic modification of human cells including embryonic stem (ES) cells. Using four ubiquitous promoters--cytomegalovirus (CMV), cytomegalovirus immediate-early enhancer/chicken beta-actin hybrid (CAG), phosphoglycerate kinase (PGK), and human elongation factor-1alpha (EF1alpha)--in a lentiviral vector to drive the expression of the enhanced green fluorescent protein (EGFP) gene in human ES cells and mouse ES cells, we determined the extent of EGFP suppression by assessing the percentage of cells that were transduced with the EGFP gene but did not fluoresce green. A much higher level of transgene suppression was observed in human ES cells as compared to mouse ES cells. The suppression was also highly promoter dependent, leading to inactivation of more than 95% of the EGFP genes under the CMV or CAG promoter while only 55% under the PGK promoter. No promoter-dependent suppression was observed in transient transfection of human ES cells. Thus, the common phenomenon of poor transgene expression in human ES cells may be caused mainly by suppression of the transgene right after transduction and integration. Cautions should be taken to choose the optimal promoter when lentiviruses are used for genetic modification of human ES cells.