Gut microbiota profile of Indonesian stunted children and children with normal nutritional status

Distinct gut microbiota and metabolome features of tissue-specific insulin resistance in overweight and obesity

Insulin resistance (IR) is an early marker of cardiometabolic deterioration which may develop heterogeneously in key metabolic organs, including the liver (LIR) and skeletal muscle (MIR). This tissue-specific IR is characterized by distinct metabolic signatures, but the role of the gut microbiota in its etiology remains unclear. Here, we profiled the gut microbiota, its metabolites and the plasma metabolome in individuals with either a LIR or MIR phenotype (n = 233). We observed distinct microbial community structures LIR and MIR, and higher short-chain fatty acid (SCFA) producing bacteria, fecal SCFAs and branched-chain fatty acids and a higher postprandial plasma glucagon-like-peptide-1 response in LIR. In addition, we found variations in metabolome profiles and phenotype-specific associations between microbial taxa and functional metabolite groups. Overall, our study highlights association between gut microbiota and its metabolites composition with IR heterogeneity that can be targeted in precision-based strategies to improve cardiometabolic health. Clinicaltrials.gov registration: NCT03708419.

Salivary microbiome profile shifts after scaling in stunted children

OBJECTIVE

Stunting is a condition of impaired growth in children resulting from chronic malnutrition, characterized by shorter stature compared to peers of the same age. This condition leads to salivary gland dysfunction, which triggers oral dysbiosis and increases the risk of periodontal disease in children. Scaling and root planing (SRP) is the gold standard treatment for periodontal disease, aimed at reducing pathogenic bacterial populations. This study aimed to evaluate the effect of SRP treatment on the oral microbiome profile in the saliva of stunted children. A pre- and post-test study design was employed, involving 10 elementary school children divided into two groups: normal children and stunted children. Each participant underwent scaling, with saliva samples collected before and after the procedure. The oral microbiome profile was analyzed using next-generation sequencing, generating taxonomic data at the phylum, genus, and species level.

RESULT

Statistical analysis revealed significant changes in the gingival index, a clinical parameter, in the normal group but not in the stunted group. Scaling resulted in shifts in the microbiome profile in both groups, with the dominant phyla identified as Proteobacteria, Bacteroidota, and Firmicutes. Scaling procedure alters the oral microbiome profile in stunted children without affecting the clinical parameter.

The forgotten link: how the oral microbiome shapes childhood growth and development

Childhood stunting, defined as impaired linear growth and development, remains a significant global health challenge with long-term consequences on cognitive and physical well-being. Emerging evidence highlights the pivotal role of the oral microbiome-a dynamic microbial ecosystem-in influencing nutritional status, immune response, and overall systemic health. This review explores the intricate interplay between the oral microbiome and stunting, emphasizing mechanisms such as microbial dysbiosis, its impact on nutrient absorption, and immune modulation. Disruptions in the oral microbiome can lead to nutrient malabsorption and systemic inflammation, further exacerbating growth impairments in children. Furthermore, the potential for microbiome-targeted diagnostics and interventions, including probiotics and prebiotics, offers novel strategies to address stunting. A deeper understanding of these interactions may inform innovative diagnostic tools and therapeutic interventions aimed at mitigating stunting through oral microbiome modulation. Integrating oral microbiome research into stunting prevention efforts could provide valuable insights for public health strategies to improve child growth and development, particularly in resource-limited settings. Future research should focus on elucidating the molecular pathways linking the oral microbiome to stunting and developing personalized interventions that optimize microbiome health in early life.

Association of Gut Microbiota Composition with Stunting Incidence in Children under Five in Jakarta Slums

BACKGROUND

Stunting can be linked to various factors, one of which is dysbiosis. This study aims to analyze the microbiota composition and related contributing factors of stunted and non-stunted children in the slum areas of Jakarta.

METHODS

The subjects in this study included 21 stunted (HAZ ≤ -2SD) and 21 non-stunted children (-2SD ≤ HAZ ≤ 3SD) aged 2-5 years. Microbiota analysis was performed by extracting DNA from the subjects' feces and then via 16S rRNA sequencing using next-generation sequencing (NGS).

RESULTS

The results of this study showed that in stunted children, the abundance of Mitsuokella (24,469 OTUs), Alloprevotella (23,952 OTUs), and Providencia alcalifaciens (861 OTUs) was higher, while in non-stunted children, that of Blautia (29,755 OTUs), Lachnospiraceae (6134 OTUs), Bilophila (12,417 OTUs), Monoglobus (484 OTUs), Akkermansia muciniphila (1116 OTUs), Odoribacter splanchnicus (42,993 OTUs), and Bacteroides clarus (8900 OTUs) was higher. Differences in microbiota composition in the two groups were influenced by nutrient intake, birth history, breastfeeding history, handwashing habits before eating, drinking water sources, and water sources for other activities.

CONCLUSIONS

This study highlights that stunted children have a significantly different gut microbiota composition compared to non-stunted children, with higher levels of pathogenic bacteria and lower levels of beneficial bacteria. Future research should focus on interventions that can improve the gut microbiota composition to prevent stunting in children.

Faecal microbiota and cytokine profiles of rural Cambodian infants linked to diet and diarrhoeal episodes

The gut microbiota of infants in low- to middle-income countries is underrepresented in microbiome research. This study explored the faecal microbiota composition and faecal cytokine profiles in a cohort of infants in a rural province of Cambodia and investigated the impact of sample storage conditions and infant environment on microbiota composition. Faecal samples collected at three time points from 32 infants were analysed for microbiota composition using 16S rRNA amplicon sequencing and concentrations of faecal cytokines. Faecal bacterial isolates were subjected to whole genome sequencing and genomic analysis. We compared the effects of two sample collection methods due to the challenges of faecal sample collection in a rural location. Storage of faecal samples in a DNA preservation solution preserved Bacteroides abundance. Microbiota analysis of preserved samples showed that Bifidobacterium was the most abundant genus with Bifidobacterium longum the most abundant species, with higher abundance in breast-fed infants. Most infants had detectable pathogenic taxa, with Shigella and Klebsiella more abundant in infants with recent diarrhoeal illness. Neither antibiotics nor infant growth were associated with gut microbiota composition. Genomic analysis of isolates showed gene clusters encoding the ability to digest human milk oligosaccharides in B. longum and B. breve isolates. Antibiotic-resistant genes were present in both potentially pathogenic species and in Bifidobacterium. Faecal concentrations of Interlukin-1alpha and vascular endothelial growth factor were higher in breast-fed infants. This study provides insights into an underrepresented population of rural Cambodian infants, showing pathogen exposure and breastfeeding impact gut microbiota composition and faecal immune profiles.

Establishment and perturbation of human gut microbiome: common trends and variations between Indian and global populations

Human gut microbial species are crucial for dietary metabolism and biosynthesis of micronutrients. Digested products are utilised by the host as well as several gut bacterial species. These species are influenced by various factors such as diet, age, geographical location, and ethnicity. India is home to the largest human population in the world. It is spread across diverse ecological and geographical locations. With variable dietary habits and lifestyles, Indians have unique gut microbial composition. This review captures contrasting and common trends of gut bacterial community establishment in infants (born through different modes of delivery), and how that bacterial community manifests itself along infancy, through old age between Indian and global populations. Because dysbiosis of the gut community structure is associated with various diseases, this review also highlights the common and unique bacterial species associated with various communicable as well as noncommunicable diseases such as diarrhoea, amoebiasis, malnutrition, type 2 diabetes, obesity, colorectal cancer, inflammatory bowel disease, and gut inflammation and damage to the brain in the global and Indian population.

Systematic review of associations between gut microbiome composition and stunting in under-five children

Childhood stunting is associated with impaired cognitive development and increased risk of infections, morbidity, and mortality. The composition of the enteric microbiota may contribute to the pathogenesis of stunting. We systematically reviewed and synthesized data from studies using high-throughput genomic sequencing methods to characterize the gut microbiome in stunted versus non-stunted children under 5 years in LMICs. We included 14 studies from Asia, Africa, and South America. Most studies did not report any significant differences in the alpha diversity, while a significantly higher beta diversity was observed in stunted children in four out of seven studies that reported beta diversity. At the phylum level, inconsistent associations with stunting were observed for Bacillota, Pseudomonadota, and Bacteroidota phyla. No single genus was associated with stunted children across all 14 studies, and some associations were incongruent by specific genera. Nonetheless, stunting was associated with an abundance of pathobionts that could drive inflammation, such as Escherichia/Shigella and Campylobacter, and a reduction of butyrate producers, including Faecalibacterium, Megasphera, Blautia, and increased Ruminoccoccus. An abundance of taxa thought to originate in the oropharynx was also reported in duodenal and fecal samples of stunted children, while metabolic pathways, including purine and pyrimidine biosynthesis, vitamin B biosynthesis, and carbohydrate and amino acid degradation pathways, predicted linear growth. Current studies show that stunted children can have distinct microbial patterns compared to non-stunted children, which could contribute to the pathogenesis of stunting.

Stunting and Gut Microbiota: A Literature Review

Stunting, a condition characterized by impaired growth and development in children, remains a major public health concern worldwide. Over the past decade, emerging evidence has shed light on the potential role of gut microbiota modulation in stunting. Gut microbiota dysbiosis has been linked to impaired nutrient absorption, chronic inflammation, altered short-chain fatty acid production, and perturbed hormonal and signaling pathways, all of which may hinder optimal growth in children. This review aims to provide a comprehensive analysis of existing research exploring the bidirectional relationship between stunting and the gut microbiota. Although stunting can alter the gut microbial community, microbiota dysbiosis may exacerbate it, forming a vicious cycle that sustains the condition. The need for effective preventive and therapeutic strategies targeting the gut microbiota to combat stunting is also discussed. Nutritional interventions, probiotics, and prebiotics are among the most promising approaches to modulate the gut microbiota and potentially ameliorate stunting outcomes. Ultimately, a better understanding of the gut microbiota-stunting nexus is vital for guiding evidence-based interventions that can improve the growth and development trajectory of children worldwide, making substantial strides toward reducing the burden of stunting in vulnerable populations.

The infant gut microbiome and cognitive development in malnutrition

Malnutrition affects 195 million children under the age of five worldwide with long term effects that include impaired cognitive development. Brain development occurs rapidly over the first 36 months of life. Whilst seemingly independent, changes to the brain and gut microbiome are linked by metabolites, hormones, and neurotransmitters as part of the gut-brain axis. In the context of severe malnutrition, the composition of the gut microbiome and the repertoire of biochemicals exchanged via the gut-brain axis vary when compared to healthy individuals. These effects are primarily due to the recognized interacting determinants, macro- and micronutrient deficiencies, infection, infestations and toxins related to poor sanitation, and a dearth of psycho-social stimulation. The standard of care for the treatment of severe acute malnutrition is focused on nutritional repletion and weight restoration through the provision of macro- and micronutrients, the latter usually in excess of recommended dietary allowances (RDA). However, existing formulations and supplements have not been designed to specifically address key recovery requirements for brain and gut microbiome development. Animal model studies indicate that treatments targeting the gut microbiome could improve brain development. Despite this, research on humans targeting the gut microbiome with the aim of restoring brain functionality are scarce. We conclude that there is a need for assessment of cognition and the use of various tools that permit visualization of the brain anatomy and function (e.g., Magnetic resonance imaging (MRI), functional near-infrared spectroscopy (fNIRS), electroencephalogram (EEG)) to understand how interventions targeting the gut microbiome impact brain development.

Gut microbiota differences in stunted and normal-lenght children aged 36-45 months in East Nusa Tenggara, Indonesia

The role of the gut microbiota in energy metabolism of the host has been established, both in overweight/obesity, as well as in undernutrition/stunting. Dysbiosis of the gut microbiota may predispose to stunting. The aim of this study was to compare the gut microbiota composition of stunted Indonesian children and non-stunted children between 36 and 45 months from two sites on the East Nusa Tenggara (ENT) islands. Fecal samples were collected from 100 stunted children and 100 non-stunted children in Kupang and North Kodi. The gut microbiota composition was determined by sequencing amplicons of the V3-V4 region of the 16S rRNA gene. Moreover, fecal SCFA concentrations were analyzed. The microbiota composition was correlated to anthropometric parameters and fecal metabolites. The phyla Bacteroidetes (Bacteroidota; q = 0.014) and Cyanobacteria (q = 0.049) were significantly higher in stunted children. Three taxa at genus levels were consistently significantly higher in stunted children at both sampling sites, namely Lachnoclostridium, Faecalibacterium and Veillonella (q < 7 * 10-4). These and 9 other taxa positively correlated to the z-score length-for-age (zlen), while 11 taxa negatively correlated with zlen. Several taxa also correlated with sanitary parameters, some of which were also significantly different between the two groups. All three fecal SCFA concentrations (acetate, propionate and butyrate) and their total were lower in stunted children compared to non-stunted children, although not significant for butyrate, indicating lower energy-extraction by the gut microbiota. Also, since SCFA have been shown to be involved in gut barrier function, barrier integrity may be affected in the stunted children. It remains to be seen if the three taxa are involved in stunting, or are changed due to e.g. differences in diet, hygiene status, or other factors. The observed differences in this study do not agree with our previous observations in children on Java, Indonesia. There are differences in infrastructure facilities such as clean water and sanitation on ENT and Java, which may contribute to the differences observed. The role of the gut microbiota in stunting therefore requires more in depth studies. Trial registration: the trial was registered at ClinicalTrials.gov with identifier number NCT05119218.

Examination of sex-specific interactions between gut microbiota and host metabolism after 12-week combined polyphenol supplementation in individuals with overweight or obesity

Polyphenols exert beneficial effects on host metabolism, which may be mediated by the gut microbiota. We investigated sex-specific differences in microbiota composition and interactions with cardiometabolic parameters after polyphenol supplementation in individuals with overweight/obesity. In a double-blind, randomized, placebo-controlled trial, 19 women and 18 men with normal glucose tolerance and body mass index >25 kg/m2 received epigallocatechin-3-gallate and resveratrol (EGCG+RES, 282 + 80 mg/d) or placebo supplements for 12 weeks. Fecal microbiota composition (16S rRNA gene amplicon sequencing, V3-V4 region), in vivo whole-body fat oxidation (indirect calorimetry), and mitochondrial respiration in permeabilized skeletal muscle fibers (SkM-Ox; ex vivo respirometry) were determined pre- and post-intervention. Overall, EGCG+RES supplementation did not affect gut microbiota composition. Akkermansia, Ruminococcaceae UCG-002, Subdoligranulum, and Lachnospiraceae UCG-004 were more abundant, while Veillonella, Tyzzerella 4, Clostridium innocuum group, Ruminococcus gnavus group, Escherichia-Shigella, and an uncultured Ruminococcaceae family genus were less abundant in women compared to men. In women, only baseline Eubacterium ventriosum group abundance correlated with EGCG+RES-induced changes in SkM-Ox. In men, low Dorea, Barnsiella, Anaerotruncus, Ruminococcus, Subdoligranulum, Coprococcus, Eubacterium ventriosum group, Ruminococcaceae UCG-003, and a Ruminococcaceae family genus abundance, and high Blautia abundance at baseline were associated with improvements in SkM-Ox. Changes in whole-body fat oxidation were not associated with gut microbiota features. We conclude that baseline microbiota composition predicts changes in SkM-Ox as a result of EGCG+RES supplementation in men but not in women. Men may be more prone to diet-induced, gut microbiota-related improvements in cardiometabolic health. These sex-differences should be further investigated in future precision-based intervention studies.

Association of Pooled Fecal Microbiota on Height Growth in Children According to Enterotypes

OBJECTIVES

The association between fecal microbiota and height in children has yielded conflicting findings, warranting further investigation into potential differences in fecal bacterial composition between children with short stature and those of standard height based on enterotypes (ETs).

METHODS

According to the height z score for age and gender, the children were categorized into normal-stature (NS; n = 335) and short-stature (SS; n = 152) groups using a z score of -1.15 as a separator value. The human fecal bacterial FASTA/Q files (n = 487) were pooled and analyzed with the QIIME 2 platform with the National Center for Biotechnology Information alignment search tool. According to ETs, the prediction models by the machine learning algorithms were used for explaining SS, and their quality was validated.

RESULTS

The proportion of SS was 16.4% in ET Enterobacteriaceae (ET-E) and 68.1% in Prevotellaceae (ET-P). The Chao1 and Shannon indexes were significantly lower in the SS than in the NS groups only in ET-P. The fecal bacteria related to SS from the prediction models were similar regardless of ETs. However, in network analysis, the negative correlations between fecal bacteria in the NS and SS groups were much higher in the ET-P than in the ET-E. In the metagenome function, fecal bacteria showed an inverse association of biotin and secondary bile acid synthesis and downregulation of insulin/insulin-like growth factor-1-driven phosphoinositide 3-kinase Akt signaling and AMP-kinase signaling in the SS group compared with the NS group in both ETs.

CONCLUSION

The gut microbial compositions in children were associated with height. Strategies to modify and optimize the gut microbiota composition should be investigated for any potential in promoting height in children.

Malnourished Microbes: Host-Microbiome Interactions in Child Undernutrition

Childhood undernutrition is a major global health burden that is only partially resolved by nutritional interventions. Both chronic and acute forms of child undernutrition are characterized by derangements in multiple biological systems including metabolism, immunity, and endocrine systems. A growing body of evidence supports a role of the gut microbiome in mediating these pathways influencing early life growth. Observational studies report alterations in the gut microbiome of undernourished children, while preclinical studies suggest that this can trigger intestinal enteropathy, alter host metabolism, and disrupt immune-mediated resistance against enteropathogens, each of which contribute to poor early life growth. Here, we compile evidence from preclinical and clinical studies and describe the emerging pathophysiological pathways by which the early life gut microbiome influences host metabolism, immunity, intestinal function, endocrine regulation, and other pathways contributing to child undernutrition. We discuss emerging microbiome-directed therapies and consider future research directions to identify and target microbiome-sensitive pathways in child undernutrition.

Defining the Relationship of Gut Microbiota, Immunity, and Cognition in Early Life-A Narrative Review

Recently, the immune system has been identified as one of the possible main bridges which connect the gut-brain axis. This review aims to examine available evidence on the microbiota-immunity-cognitive relationship and its possible effects on human health early in life. This review was assembled by compiling and analyzing various literature and publications that document the gut microbiota-immune system-cognition interaction and its implications in the pediatric population. This review shows that the gut microbiota is a pivotal component of gut physiology, with its development being influenced by a variety of factors and, in return, supports the development of overall health. Findings from current research focus on the complex relationship between the central nervous system, gut (along with gut microbiota), and immune cells, highlighting the importance of maintaining a balanced interaction among these systems for preserving homeostasis, and demonstrating the influence of gut microbes on neurogenesis, myelin formation, the potential for dysbiosis, and alterations in immune and cognitive functions. While limited, evidence shows how gut microbiota affects innate and adaptive immunity as well as cognition (through HPA axis, metabolites, vagal nerve, neurotransmitter, and myelination).

Dietary interventions, the gut microbiome, and aggressive behavior: Review of research evidence and potential next steps

Research in biosocial criminology and other related disciplines has established links between nutrition and aggressive behavior. In addition to observational studies, randomized trials of nutritional supplements like vitamins, omega-3 fatty acids, and folic acid provide evidence of the dietary impact on aggression. However, the exact mechanism of the diet-aggression link is not well understood. The current article proposes that the gut microbiome plays an important role in the process, with the microbiota-gut-brain axis serving as such a mediating mechanism between diet and behavior. Based on animal and human studies, this review synthesizes a wide array of research across several academic fields: from the effects of dietary interventions on aggression, to the results of microbiota transplantation on socioemotional and behavioral outcomes, to the connections between early adversity, stress, microbiome, and aggression. Possibilities for integrating the microbiotic perspective with the more traditional, sociologically oriented theories in criminology are discussed, using social disorganization and self-control theories as examples. To extend the existing lines of research further, the article considers harnessing the experimental potential of noninvasive and low-cost dietary interventions to help establish the causal impact of the gut microbiome on aggressive behavior, while adhering to the high ethical standards and modern research requirements. Implications of this research for criminal justice policy and practice are essential: not only can it help determine whether the improved gut microbiome functioning moderates aggressive and violent behavior but also provide ways to prevent and reduce such behavior, alone or in combination with other crime prevention programs.

Study of the importance of protein needs for catch-up growth in Indonesian stunted children: a narrative review

Stunting is a chronic nutritional deficiency due to various adverse cross-sectoral environmental conditions, including food intake. This influences the linear growth and development of children's brains and their cognitive function. Providing interventions to meet stunted children's protein needs tends to prevent the further abnormal development of cognitive functions. High-protein foods are supplied from various edible local commodities in Indonesia. Therefore, this study aims to demonstrate the importance of feeding stunted children with high-protein diets and provide insight that local food ingredients in the country have growth-promoting potential. Through Google Scholar, PubMed, Science Direct, and Nature, 107 articles were obtained with keywords related to stunting, such as protein intake, catch-up growth + stunting, and adverse effect + catch-up growth. The preferred citations randomized-controlled trials and systematic reviews relevant to the study question were compiled using Mendeley version 1.19.8. Based on the literature review results, stunting is hereditary and affects the quality of generations. The adequacy of protein needs is closely related to growth and development, hence, foods containing a high amount of the nutrient facilitate catch-up growth in stunted children. This conclusion is expected to provide information to policymakers and health agencies in the country concerning the education related to high nutritional local food, which can be reached by the community. Interventions with high-protein-containing local foods ought to be tailored to dietary needs and accompanied by monitoring for the presence or absence of unreasonable weight gain to prevent overweight or obesity.

OUP accepted manuscript

The intestinal microbiota plays a crucial role in health and changes in its composition are linked with major global human diseases. Fully understanding what shapes the human intestinal microbiota composition and knowing ways of modulating the composition are critical for promotion of life-course health, combating diseases, and reducing global health disparities. We aim to provide a foundation for understanding what shapes the human intestinal microbiota on an individual and global scale, and how interventions could utilize this information to promote life-course health and reduce global health disparities. We briefly review experiences within the first 1,000 days of life and how long-term exposures to environmental elements or geographic specific cultures have lasting impacts on the intestinal microbiota. We also discuss major public health threats linked to the intestinal microbiota, including antimicrobial resistance and disappearing microbial diversity due to globalization. In order to promote global health, we argue that the interplay of the larger ecosystem with intestinal microbiota research should be utilized for future research and urge for global efforts to conserve microbial diversity.

Effect of Lactobacillus plantarum DAD-13 and Fructo-oligosaccharides on Short-Chain Fatty Acid Profile and Nutritional Status in Indonesian Stunting Children

BACKGROUND: Chronic gut inflammation is a generalized disturbance of small intestine structure and function is likely to play a large role in the incidence of stunting. It will be disturbances the absorption of nutrients, therefore, it can indirectly reduce on nutritional status. AIM: The aim of this study is to examine the effect of Lactobacillus plantarum DAD-13 and fructooligosaccharide on short-chain fatty acid (SCFA) profile and nutritional status in Indonesian stunting children. METHODS: The study design was used double-blind randomized placebo-controlled trial, 39 stunting children under five received daily oral supplementations of L. plantarum DAD-13 1 × 1010 cfu and fructooligosaccharide 700 mg (symbiotic group) or placebo group for 90 days. SCFA profile was analyzed using gas chromatography and nutritional status was assessed by WAZ, HAZ, and WHZ. RESULTS: The result shows in symbiotic and control group, the mean age was 26 ± 8.34 and 29 ± 5.78, and the mean weight was 8.5 ± 0.94 kg and 9.0 ± 0.82 kg, while the mean height was 78.96 ± 5.4 cm and 80.9 ± 4.55 cm, respectively. Concentrations of acetate, propionate, and butyrate in the symbiotic group after consumption were 17.10 ± 2.97, 7.70 ± 2.05, and 7.47 ± 1.76 while in placebo group 12.44 ± 3.61, 5.20 ± 1.66, and 6.12 ± 1.16, respectively. There was a significant difference in the mean SCFA concentration between the symbiotic and placebo groups (p < 0.05), where the SCFA concentration in the symbiotic group was significantly higher than the placebo group. Nutritional status (WAZ, HAZ, and WHZ) was observed significantly in symbiotic group (p < 0.05), only on WHZ has cutoff point >-2SD after the intervention, while WAZ and HAZ <-2SD. CONCLUSIONS: L. plantarum DAD-13 and fructooligosaccharide 90 days supplementation have increase acetate, butyrate, and propionate that are important fuels for intestinal epithelial cells that can play an important role in the maintenance of health.

Alterations in children's sub-dominant gut microbiota by HIV infection and anti-retroviral therapy

Objective

We investigated the impact of human immunodeficiency virus (HIV) infection and anti-retroviral therapy (ART) on the gut microbiota of children.

Design

This cross-sectional study investigated the gut microbiota of children with and without HIV.

Methods

We collected fecal samples from 59 children with HIV (29 treated with ART [ART(+)] and 30 without ART [HIV(+)]) and 20 children without HIV [HIV(–)] in Vietnam. We performed quantitative RT-PCR to detect 14 representative intestinal bacteria targeting 16S/23S rRNA molecules. We also collected the blood samples for immunological analyses.

Results

In spearman’s correlation analyses, no significant correlation between the number of dominant bacteria and age was found among children in the HIV(−) group. However, the number of sub-dominant bacteria, including Streptococcus, Enterococcus, and Enterobacteriaceae, positively correlated with age in the HIV(−) group, but not in the HIV(+) group. In the HIV(+) group, Clostridium coccoides group positively associated with the CD4⁺ cell count and its subsets. In the ART(+) group, Staphylococcus and C. perfringens positively correlated with CD4⁺ cells and their subsets and negatively with activated CD8⁺ cells. C. coccoides group and Bacteroides fragilis group were associated with regulatory T-cell counts. In multiple linear regression analyses, ART duration was independently associated with the number of C. perfringens, and Th17 cell count with the number of Staphylococcus in the ART(+) group.

Conclusions

HIV infection and ART may influence sub-dominant gut bacteria, directly or indirectly, in association with immune status in children with HIV.

Differences in immune status and fecal SCFA between Indonesian stunted children and children with normal nutritional status

We recently showed that the gut microbiota composition of stunted children was different from that of children with normal nutritional status. Here, we compared immune status and fecal microbial metabolite concentrations between stunted and normal children, and we correlated macronutrient intake (including energy), metabolites and immune status to microbiota composition. The results show that macronutrient intake was lower in stunted children for all components, but after correction for multiple comparison significant only for energy and fat. Only TGF-β was significantly different between stunted children and children of normal nutritional status after correction for multiple comparisons. TNF-alpha, IL-10, lipopolysaccharide binding protein in serum and secretory IgA in feces were not significantly different. Strikingly, all the individual short-chain and branched-chain fatty acids were higher in fecal samples of stunted children (significant for acetate, valerate and total SCFA). These metabolites correlated with a number of different microbial taxa, but due to extensive cross-feeding between microbes, did not show a specific pattern. However, the energy-loss due to higher excretion in stunted children of these metabolites, which can be used as substrate for the host, is striking. Several microbial taxa also correlated to the intake of macronutrients (including dietary fibre) and energy. Eisenbergiella positively correlated with all macronutrients, while an uncharacterized genus within the Succinivibrionaceae family negatively correlated with all macronutrients. These, and the other correlations observed, may provide indication on how to modulate the gut microbiota of stunted children such that their growth lag can be corrected. Trail registered at https://clinicaltrials.gov/ct2/show/NCT04698759.