Effect of dietary zinc supplementation on the gastrointestinal microbiome and host gene expression in the mouse model of autism spectrum disorder.

Shank gene variants are implicated in ~1% of people with autism, and mice lacking exhibit autism-like behaviours. Zinc deficiency and gastrointestinal problems can be common among people with autism, and zinc is a key element required for SHANK protein function and gut development. In mice, a supplementary zinc diet reverses autism-like behaviours.

Investigating Multi-Omic Signatures of Ethnicity and Dysglycaemia in Asian Chinese and European Caucasian Adults: Cross-Sectional Analysis of the TOFI_Asia Study at 4-Year Follow-Up.

Type 2 diabetes (T2D) is a global health epidemic with rising prevalence within Asian populations, particularly amongst individuals with high visceral adiposity and ectopic organ fat, the so-called Thin-Outside, Fat-Inside phenotype. Metabolomic and microbiome shifts may herald T2D onset, presenting potential biomarkers and mechanistic insight into metabolic dysregulation. However, multi-omics datasets across ethnicities remain limited.

Benchmarking 16S rRNA Gene-Based Approaches to Bacterial Taxonomy Assignment Based on Amplicon Sequencing With Illumina and Oxford Nanopore.

Research investigating the microbial community of an ecosystem or animal can involve a range of methodologies, including sequencing technology, bioinformatic software and taxonomy database. Researchers may utilise short-read sequencing on Illumina MiSeq or long-read sequencing on platforms like Oxford Nanopore to obtain different research outcomes, for example, enhanced identification of microbes at species or strain level with Nanopore. However, replicability across these techniques is not well studied, while the technique used to process reads into microbial taxa may also result in different taxonomy assignments.

Design and conduct of a full diet-controlled, parallel, 2-week residential trial for diabetes prevention without weight loss in Asian Chinese and European Caucasian adults with prediabetes: the New Zealand SYNERGY study.

Background: The causal underpinning of increased metabolic risk and previously observed dichotomous plasma metabolome in Asian Chinese vs. European Caucasian remains undetermined and may be hypothesised as attributed to ethnicity (genetic background), pathology (dysglycaemia) and/or lifestyle (habitual diet). We aimed to investigate the underlying cause(s) and the effect of dietary intervention on biomarkers of type 2 diabetes (T2D) in cohorts with prediabetes.

Season, Body Condition and Developmental Stage Influence the Gut Microbiota of the Sole Living Rhynchocephalian Reptile ().

Seasonality plays a crucial role for many species, especially reptiles. In multiple reptile species, seasonality has been linked to shifts in the gut microbiota, influenced by factors, such as ambient temperature, food availability and shifting host function across different seasons. We tested whether the tuatara, an endemic New Zealand reptile and the sole extant member of the order Rhynchocephalia, maintains a stable gut microbiota over 2 years of sampling across three seasons (summer, autumn, spring) or if the dominant bacterial community varies with season.

Culture-Independent Species-Level Taxonomic and Functional Characterisation of Bacteroides, the Core Bacterial Genus Within Reptile Guts.

The genus Bacteroides is a widespread and abundant bacterial taxon associated with gut microbiotas. Species within Bacteroides fill many niches, including as mutualists, commensals and pathogens for their hosts. Within many reptiles, Bacteroides is a dominant, 'core' gut bacterium that sometimes exhibits increased abundance in times of food scarcity, such as during hibernation.

Diversity and cross-species transmission of viruses in a remote island ecosystem: implications for wildlife conservation.

The ability of viruses to emerge in new species is influenced by aspects of host biology and ecology, with some taxa harbouring a high diversity and abundance of viruses. However, how these factors shape virus diversity at the ecosystem scale is often unclear. To better understand the pattern and determinants of viral diversity within an ecosystem, and to describe the novel avian viruses infecting an individual avian community, we performed a metagenomic snapshot of the virome from the entire avian community on remote Pukenui/Anchor Island in Aotearoa New Zealand.

Limited gut bacterial response of tuatara (Sphenodon punctatus) to dietary manipulation and captivity.

The bacteria of a host's digestive tract play crucial roles in digestion and pathogen resistance. Hosts living in captivity often have more human interaction and antibiotic use, in addition to differences in diet and environment, compared to their wild counterparts. Consequently, wild and captive animals frequently harbour different bacterial communities.

Advancing microbiome research in Māori populations: insights from recent literature exploring the gut microbiomes of underrepresented and Indigenous peoples.

The gut microbiome plays vital roles in human health, including mediating metabolism, immunity, and the gut-brain axis. Many ethnicities remain underrepresented in gut microbiome research, with significant variation between Indigenous and non-Indigenous peoples due to dietary, socioeconomic, health, and urbanization differences. Although research regarding the microbiomes of Indigenous peoples is increasing, Māori microbiome literature is lacking despite widespread inequities that Māori populations face.

Gut microbiome of the sole surviving member of reptile order Rhynchocephalia reveals biogeographic variation, influence of host body condition and a substantial core microbiota in tuatara across New Zealand.

Tuatara are the sole extant species in the reptile order Rhynchocephalia. They are ecologically and evolutionarily unique, having been isolated geographically for ~84 million years and evolutionarily from their closest living relatives for ~250 million years. Here we report the tuatara gut bacterial community for the first time.

Gut microbiota profiles in two New Zealand cohorts with overweight and prediabetes: a Tū Ora/PREVIEW comparative study.

Obesity-related metabolic diseases such as type 2 diabetes (T2D) are major global health issues, affecting hundreds of millions of people worldwide. The underlying factors are both diverse and complex, incorporating biological as well as cultural considerations. A role for ethnicity - a measure of self-perceived cultural affiliation which encompasses diet, lifestyle and genetic components - in susceptibility to metabolic diseases such as T2D is well established.

Topiramate alters the gut microbiome to aid in its anti-seizure effect.

Introduction: There is a growing interest in the role of the gut microbiota in epilepsy, however, it is unclear if anti-seizure medications (ASMs) play a role in the gut-brain axis. To test this, we investigated the impact of the ASM topiramate on the gut microbiome of mice.

Methods: C57BL/6J mice were administered topiramate in their drinking water for 5 weeks.

16S rRNA gene-based meta-analysis of the reptile gut microbiota reveals environmental effects, host influences and a limited core microbiota.

An animal's gut microbiota plays an important role in host health, reproduction and digestion. However, many studies focus on only a few individuals or a single species, limiting our ability to recognize emergent patterns across a wider taxonomic grouping. Here, we compiled and reanalysed published 16S rRNA gene sequence data for 745 gut microbiota samples from 91 reptile species using a uniform bioinformatics pipeline to draw broader conclusions about the taxonomy of the reptile gut microbiota and the forces shaping it.

Host phylogeny shapes viral transmission networks in an island ecosystem.

Virus transmission between host species underpins disease emergence. Both host phylogenetic relatedness and aspects of their ecology, such as species interactions and predator-prey relationships, may govern rates and patterns of cross-species virus transmission and hence zoonotic risk. To address the impact of host phylogeny and ecology on virus diversity and evolution, we characterized the virome structure of a relatively isolated island ecological community in Fiordland, New Zealand, that are linked through a food web.

16S rRNA gene-based microbiota profiles from diverse avian faeces are largely independent of DNA preservation and extraction method.

The avian gut microbiota has been the subject of considerable recent attention, with potential implications for diverse fields such as the poultry industry, microbial ecology, and conservation. Faecal microbiotas are frequently used as a non-invasive proxy for the gut microbiota, however the extraction of high-quality microbial DNA from avian faeces has often proven challenging. Here we aimed to evaluate the performance of two DNA preservation methods (95% ethanol and RNAlater) and five extraction approaches (IndiSpin Pathogen Kit, QIAamp PowerFecal Pro DNA Kit, MicroGEM PrepGEM Bacteria Kit, ZymoBIOMICS DNA Miniprep Kit, and an in-house phase separation-based method) for studying the avian gut microbiota.

Effect of a 12-Week Polyphenol Rutin Intervention on Markers of Pancreatic β-Cell Function and Gut Microbiota in Adults with Overweight without Diabetes.

Supplementation with prebiotic polyphenol rutin is a potential dietary therapy for type 2 diabetes prevention in adults with obesity, based on previous glycaemic improvement in transgenic mouse models. Gut microbiota are hypothesised to underpin these effects. We investigated the effect of rutin supplementation on pancreatic β-cell function measured as C-peptide/glucose ratio, and 16S rRNA gene-based gut microbiota profiles, in a cohort of individuals with overweight plus normoglycaemia or prediabetes.

Realising respiratory microbiomic meta-analyses: time for a standardised framework.

In microbiome fields of study, meta-analyses have proven to be a valuable tool for identifying the technical drivers of variation among studies and results of investigations in several diseases, such as those of the gut and sinuses. Meta-analyses also represent a powerful and efficient approach to leverage existing scientific data to both reaffirm existing findings and generate new hypotheses within the field. However, there are currently limited data in other fields, such as the paediatric respiratory tract, where extension of original data becomes even more critical due to samples often being difficult to obtain and process for a range of both technical and ethical reasons.

Beyond the theory: From holobiont concept to microbiome engineering.

Holobiont research has increasingly moved from descriptive studies to sophisticated field- and laboratory-based manipulations; however, the extent to which changes in the holobiont persist remains largely unknown. In this Burning Question, we ask whether the underlying principles of the holobiont concept, whereby an externally applied evolutionary pressure can lead to a beneficial change in host-associated microbial community composition, could be used to facilitate microbiome engineering and thereby addition of a new ecosystem service that persists across generations. The answer to this question has potential implications for diverse fields including symbiosis, conservation and biotechnology.

Bioinformatic Approaches for Describing the Oral Microbiota.

Cultivation-independent (molecular) analysis of the oral microbiota can provide a comprehensive picture of microbial community composition, yet there is an at-times bewildering array of approaches that can be employed. This chapter introduces some of the key considerations when undertaking microbiota research and describes two alternative bioinformatic pipelines for conducting such studies. The descriptions are based on analysis of bacterial 16S ribosomal RNA gene sequences, but can be easily adapted for analysis of other microbial taxa such as fungi.

Influence of management practice on the microbiota of a critically endangered species: a longitudinal study of kākāpō chick faeces and associated nest litter.

Background: The critically endangered kākāpō is a flightless, nocturnal parrot endemic to Aotearoa New Zealand. Recent efforts to describe the gastrointestinal microbial community of this threatened herbivore revealed a low-diversity microbiota that is often dominated by Escherichia-Shigella bacteria. Given the importance of associated microbial communities to animal health, and increasing appreciation of their potential relevance to threatened species conservation, we sought to better understand the development of this unusual gut microbiota profile.

Dynamic Upper and Lower Airway Microbiotas in Paediatric Bronchiectasis Exacerbations: A Pilot Study.

Introduction: Non-cystic fibrosis bronchiectasis is a respiratory health condition with many possible aetiologies, some of which are potentially reversible in childhood with early diagnosis and appropriate treatment. It is important to understand factors which contribute to progression or potential resolution of bronchiectasis. It is evident that respiratory exacerbations are a key feature of bronchiectasis disease progression.

Gut microbiota of the threatened takahē: biogeographic patterns and conservation implications.

Background: The Aotearoa New Zealand takahē (Porphyrio hochstetteri), once thought to be extinct, is a nationally threatened flightless rail under intensive conservation management. While there has been previous research into disease-related microbes in takahē, little is known about the microbes present in the gastrointestinal tract. Given the importance of gut-associated microbes to herbivore nutrition and immunity, knowledge of these communities is likely to be of considerable conservation value.

Bacterial Signatures of Paediatric Respiratory Disease: An Individual Participant Data Meta-Analysis.

The airway microbiota has been linked to specific paediatric respiratory diseases, but studies are often small. It remains unclear whether particular bacteria are associated with a given disease, or if a more general, non-specific microbiota association with disease exists, as suggested for the gut. We investigated overarching patterns of bacterial association with acute and chronic paediatric respiratory disease in an individual participant data (IPD) meta-analysis of 16S rRNA gene sequences from published respiratory microbiota studies.