Search Results (233)

The breast microbiome remains stable throughout a woman’s life. The breast is not a sterile organ, and its microbiota exhibits a distinct composition compared to other body sites. The breast microbiome is a community characterized by an abundance of Proteobacteria and Firmicutes, which represent the result of host microbial adaptation to the fatty acid environment in the tissue. The breast microbiome demonstrates dynamic adaptability during lactation, responding to maternal physiological changes and infant interactions. This microbial plasticity modulates local immune responses, maintains epithelial integrity, and supports tissue homeostasis, thereby influencing both breast health and milk composition. Disruptions in this balance, the dysbiosis, are closely linked to inflammatory breast conditions such as mastitis. Risk factors for breast cancer (BC) include genetic mutations, late menopause, obesity, estrogen metabolism, and alterations in gut microbial diversity. Gut microbiota can increase estrogen bioavailability by deconjugating estrogen-glucuronide moieties. Perturbations of this set of bacterial genes and metabolites, called the estrobolome, increases circulating estrogens and the risk of BC. Fusobacterium nucleatum has recently been associated with BC. It moves from the oral cavity to other body sites hematogenously. This review deals with the characteristics of the breast microbiome, with a focus on F. nucleatum, highlighting its dual role in promoting tumor growth and modulating immune responses. F. nucleatum acts both on the Wnt/β-catenin pathway by positively regulating MYC expression and on apoptosis by inhibiting caspase 8. Furthermore, F. nucleatum binds to TIGIT and CEACAM1, inhibiting T-cell cytotoxic activity and protecting tumor cells from immune cell attack. F. nucleatum also inhibits T-cell function through the recruitment of myeloid suppressor cells (MDSCs). These cells express PD-L1, which further reduces T-cell activation. A deeper understanding of F. nucleatum biology and its interactions with host cells and co-existing symbiotic microbiota could aid in the development of personalized anticancer therapy. Full article

The composition of the gut and/or tumor microbiome has been intricately involved in the onset of carcinogenesis, tumor progression, therapy response, and patient outcomes in diverse solid cancers. The microbiome type, composition, and their metabolome have been functionally implicated in the multifarious cellular processes, transformation, proliferation, tumor immune evasion, cellular migration, etc. Despite such compelling evidence on the role of microbiome interactions in cancer, the realization of their role in neuroblastoma (NB), the deadly extracranial tumor in infants is few and fragmentary. This review comprehends the composition, diversity, and significance of microbiota in human health. Further, this review discusses the microbiota composition, their mode of action, and their signaling flow through and cellular processes in diverse cancers including NB. Precisely, this study for the first time has realized the functional relevance and clinical significance of the gut and tumor microbiome for NB. Interestingly, large cohort clinical and preclinical in vivo models of NB realized the following: gut microbiota predicts the risk for NB; postnatal (and or not maternal transmission) microbiome rearrangements; gut microbial effect on NB pathogenesis; tumor-altering gut microbial composition; microbial composition predicts treatment outcomes in NB; prebiotic remedies for stabilizing NB-associated microbial rearrangements; microbial composition in tumor-infiltrating microbiota predicts NB outcomes. Full article

Human milk bacteria contribute to gut microbiome establishment in breastfed infants. Although breastfeeding is recommended throughout infancy, temporal variation in the milk microbiome—particularly beyond solid food introduction—remains understudied. We analyzed 539 milk samples from 83 mother–infant dyads between 1 week and 12 months postpartum using full-length 16S rRNA gene sequencing. The microbiota was dominated by Streptococcus (34%), Cutibacterium (12%), and Staphylococcus (9%), with marked inter-individual variation. Microbiome profiles remained largely stable across lactation, with only six taxa showing temporal fluctuations, including increases in typical oral bacteria such as Streptococcus salivarius, Streptococcus lactarius, Rothia mucilaginosa, and Granulicatella adiacens. Richness and evenness were higher at 1 week compared to 1 month postpartum (p = 0.00003 and p = 0.007, respectively), then stabilized. Beta diversity also remained stable over time. Maternal pre-pregnancy BMI was positively associated with Gemella haemolysans (p = 0.016), while Haemophilus parainfluenzae was more abundant in milk from mothers with allergies (p = 0.003) and those who gave birth in autumn or winter (p = 0.006). The introduction of solid food was linked to minor taxonomic shifts. Overall, the milk microbiome remained robustly stable over the first year of lactation, with limited but notable fluctuations in specific taxa. This study supports the role of human milk as a consistent microbial source for infants and identifies maternal BMI, allergy status, and birth season as key variables warranting further investigation. Full article

The first few days following the birth are a vulnerable time for the neonate. Sick infants experience various interventions during their stay in the neonatal unit in order to stay alive and grow. Acquisition of gut microbes is critical for the short- and long-term health of the neonate. At a time when the gut microbiome is starting to take shape, crucial interventions directed at improving the growth, development and survival of the neonate impact its development. Events prior to and after the birth of the neonate, such as maternal conditions, antibiotic exposure, type of feeds, supplemental probiotics, and neonatal intensive care environment, contribute significantly to shaping the gut microbiome over the first few weeks and maintain its healthy balance crucial for long-term health. In this comprehensive review, we address common interventions the neonate is exposed to in its journey and their impact on gut microbiome, and discuss various interventions that minimize the dysbiosis of the gut. Full article

Although age-related changes in the gut microbiome of pigs have been extensively studied, the dynamic patterns of fecal microbiota and SCFAs during the gestation-to-weaning period in sows remain poorly characterized. We aim to characterize the changes in fecal microbiota and SCFAs from pregnancy to weaning, and to investigate their associations with maternal weight gain during gestation. We systematically collected 100 fecal samples at four time points (day 30 of pregnancy (T1), 1–2 days before delivery (T2), day 10 after delivery (T3), and day 21 of weaning stage (T3)), and measured the body weight of sows at T1 (132 kg ± 10.8) and T2 (205 kg ± 12.1). The primary nutrient components of the diets during the gestation and lactation periods are summarized. All fecal samples were subjected to 16S rRNA gene sequencing. We found that a high proportion of crude fiber (bran) is a key feature of the gestation diet, which may affect enterotype shifts and gut microbial composition. Sows fed a high-fiber diet showed significant enrichment of gut microbiota, including genera such as Prevotellaceae_UCG-003, Prevotellaceae_NK3B31_group, and Prevotella_9 during the gestational period (LDA score > 2). Moreover, Eubacterium_coprostanoligenes_group (average relative abundance: 5.5%) and Lachnospiraceae_NK4A136_group (average relative abundance: 2.5%) were the dominant bacteria during the lactation stage. Fecal propionate and butyrate levels were lowest in late gestation, and propionate negatively and acetate positively correlated with body weight change (p < 0.05). Additionally, certain Prevotella taxa were associated with arachidonic acid metabolism and acetate production (p < 0.05). Our study identified key microbial communities across four stages from gestation to weaning and revealed that dietary patterns can shape the sow gut microbiota. Furthermore, we observed significant correlations between SCFAs and body weight change during pregnancy. These findings provide a scientific basis and theoretical support for future strategies aimed at modulating gut microbiota and targeting SCFAs to improve maternal health and productivity throughout the gestation-to-weaning period. Full article

Background/Objectives: Caesarean section (CS) accounts for over 20% of global births and routinely involves perioperative antibiotic prophylaxis (PAP) to reduce surgical site infections. While the impact of such prophylaxis on neonatal microbiome development is well described, effects on the maternal gut microbiome remain underexplored. This systematic review synthesizes current evidence on how antibiotic prophylaxis during CS affects maternal gut microbiome composition and diversity—an underrepresented, but clinically relevant aspect of maternal–fetal medicine. Methods: A systematic literature search was conducted in Medline (PubMed), the Cochrane Library, and the WHO International Clinical Trials Registry Platform (ICTRP) through November 2024. Inclusion criteria were defined according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eligible studies used molecular techniques to report maternal gut microbiome outcomes (alpha- and beta-diversity). The search concentrated on beta-lactam antibiotics. Reference lists were screened, but no additional grey literature was searched. Synthesis followed the Synthesis Without meta-analysis (SWiM) approach. No review protocol was registered. The review received no external funding. Results: Out of 1011 records, three studies (total 286 mothers) met the inclusion criteria. All reported maternal microbiome outcomes secondarily to infant-focused research. Only one study provided pre- and post-birth stool samples. Applied antibiotic regimens, sequencing methods, and reported microbiome metrics for alpha- and beta-diversity varied considerably, thus limiting comparability of results. Due to high heterogeneity, no formal risk of bias was assessed. While taxonomic diversity changes were inconsistent, significant shifts in functional diversity metrics were observed postpartum. Conclusions: Evidence on maternal microbiome disruption following perioperative antibiotic prophylaxis in CS is methodologically fragmented and limited by small sample sizes and inconsistent antibiotic protocols. Nonetheless, functional diversity appears sensitive to antibiotic exposure. To improve clinical understanding and safety, maternal-focused studies using standardized protocols are urgently needed. The maternal microbiome may play a key role in both recovery and shaping the newborn’s early microbial environment. Full article

Background: Vitamin D is increasingly recognized not only for its role in skeletal development but also for its immunomodulatory and gastrointestinal effects. Maternal and neonatal vitamin D deficiency (VDD) has been associated with alterations in gut microbiota, impaired intestinal barrier integrity, and increased susceptibility to inflammatory conditions in neonates. However, the exact mechanisms linking perinatal vitamin D status to neonatal gastrointestinal morbidity remain incompletely understood. Methods: This review synthesizes current evidence (2015–2024) from clinical studies, animal models, and mechanistic research on the impact of VDD during pregnancy and the neonatal period on gastrointestinal health. Databases such as PubMed, Scopus, and Web of Science were systematically searched using keywords, including “vitamin D”, “neonate”, “gut microbiome”, “intestinal barrier”, and “necrotizing enterocolitis”. Results: Emerging data suggest that VDD in utero and postnatally correlates with dysbiosis, increased intestinal permeability, and elevated inflammatory responses in neonates. Notably, low 25(OH)D levels in mothers and newborns have been linked with a higher incidence of necrotizing enterocolitis (NEC), delayed gut maturation, and altered mucosal immunity. Vitamin D appears to modulate the expression of tight junction proteins, regulate antimicrobial peptides, and maintain microbial diversity through the vitamin D receptor (VDR). Conclusions: Understanding the gastrointestinal implications of early-life VDD opens a potential window for preventive strategies in neonatal care. Timely maternal supplementation and targeted neonatal interventions may mitigate gut-related morbidities and improve early-life health outcomes. Further longitudinal and interventional studies are warranted to clarify causality and optimal intervention timing. Full article

Autism spectrum disorder (ASD) is a complex neurological and developmental condition that occurs in approximately 1 in 100 children. ASD is a lifelong condition defined by difficulties with social communication, restricted interests, and repetitive behaviors, among other symptoms. Currently, we understand that there is no cure and the disorder can only be managed with occupational therapy alongside limited medical treatments. Reasons underlying the pathogenesis of ASD are still not well understood, but recent studies point to the influence of epigenetic dysregulation in ASD development, which opens up avenues to novel diagnosis and treatment options. In this review, we summarize recent findings and emerging therapeutics for ASD, with a focus on implications of epigenetic regulatory pathways and factors. We expound the implications of these findings to enable preventive measurements for mothers to reduce the impact of ASD at birth, non-invasive diagnostic tests for early detection, and personalized medicine management. Finally, we discuss several critical issues to be addressed and future directions of this important research field. Full article

Dysbiosis, or an altered microbiota composition, has been implicated in chronic endometrial inflammation and recurrent implantation failure. Despite growing research on the relationship between the genital microbiome and reproductive health, few studies have examined its role in ectopic pregnancy. Therefore, our study focuses on the microbiota of the cervical canal in women diagnosed with an ectopic pregnancy. Material and methods: The study group consisted of nine women of a reproductive age who were hospitalized at the Department of Maternal and Child Health, Gynecology and Obstetrics, Clinical Hospital of the University of Poznań, between February and September 2023. In nine patients, an ectopic pregnancy was diagnosed based on a transvaginal ultrasound examination. The swabs were collected for quantitative microbiological culture (using Amies transport medium). The microbiological analyses involved quantitative culture on selected selective and differential media, following the Standard Operating Procedure developed by the Institute of Microecology. Results: A reduced Lactobacillus spp. count (≤5 × 10⁷ CFU/mL) was observed in 78% of the patients participating in the study, including those that produce H₂O₂, i.e., with strong protective properties for the environment of the female reproductive tract. The molecular analyses revealed Ureaplasma spp. (U. parvum and U. urealyticum) in 33% of the samples (three patients). However, Chlamydia trachomatis and Mycoplasma genitalium were not detected in any of the analyzed samples. Conclusions: The ease of obtaining material and the minimally invasive nature of lower reproductive tract examinations may allow for the evaluation of microbiota imbalances, helping to identify individuals at an increased risk of reproductive complications. Full article

Background: Exposure to early life stress significantly increases the risk of psychopathology later in life. However, the impact of early life stress on the gut microbiome and its potential role in mental health outcomes remains insufficiently understood. This narrative review examines the current knowledge on how early life stress and its associated consequences may affect the gut microbiome, with a particular focus on conditions such as anxiety, depression, and post-traumatic stress disorder. Method: A comprehensive literature search was conducted in the PubMed and Web of Science databases between January and February 2025, covering studies published between 2015 and 2025. Results: Early life stress can profoundly impact cognitive function and neurodevelopment, with maternal early-life nutrition playing a significant role in modulating the effects of prenatal and postnatal stress. Early life stress influences the gut microbiome, disrupting its composition and function by altering the synthesis of microbial metabolites, neurotransmitters, and the activation of key metabolic pathways. However, the precise role of the gut microbiome in modulating stress responses during childhood and adolescence has not yet been fully elucidated. Conclusions: Several studies have demonstrated an association between early life stress and the gut microbiome. However, causality has not yet been established due to the numerous intrinsic and extrinsic factors influencing the microbiome-gut–brain axis. In the coming years, research on key microbial regulators, such as short-chain fatty acids, amino acids, and psychobiotics, may represent a promising approach for addressing central nervous system alterations linked to early life stress. Thus, further studies will be necessary to evaluate their potential as therapeutic agents. Full article

Maternal overnutrition and targeted supplements during pregnancy strongly affect fetal development in beef cattle, influencing gene expression, tissue development, and productivity after birth. As modern feeding practices often result in cows receiving energy and protein above requirements, understanding the balance between adequate nutrition and overconditioning is critical for sustainable beef production. This review synthesizes findings from recent studies on maternal overnutrition and supplementation, focusing on macronutrients (energy, protein, methionine) and key micronutrients (e.g., selenium, zinc). It evaluates the timing and impact of supplementation during different gestational stages, with emphasis on fetal muscle and adipose tissue development, immune function, and metabolic programming. The role of epigenetic mechanisms, such as DNA methylation and non-coding RNAs, is also discussed in relation to maternal dietary inputs. Mid-gestation supplementation promotes muscle growth by activating muscle-specific genes, whereas late-gestation diets enhance marbling and carcass traits. However, maternal overnutrition may impair mitochondrial efficiency, encourage fat deposition over muscle, and promote collagen synthesis, reducing meat tenderness. Recent evidence highlights sex-specific fetal programming differences, the significant impact of maternal diets on offspring gut microbiomes, and breed-specific nutritional responses, and multi-OMICs integration reveals metabolic reprogramming mechanisms. Targeted trace mineral and methionine supplementation enhance antioxidant capacity, immune function, and reproductive performance. Precision feeding strategies aligned with gestational requirements improve feed efficiency and minimize overfeeding risks. Early interventions, including protein and vitamin supplementation, optimize placental function and fetal development, supporting stronger postnatal growth, immunity, and fertility. Balancing nutritional adequacy without excessive feeding supports animal welfare, profitability, and sustainability in beef cattle systems. Full article

Although Cesarean section (C-section) delivery is often a necessary medical intervention, it also increases the risk of the infant developing chronic inflammatory, metabolic, and neurodevelopmental disorders. The association of C-section with the development of these conditions is thought to be partially mediated by the effects of the C-section on the infant’s microbiome development and subsequent immune regulation. C-section-delivered infants acquire a different set of microbes compared with infants who are vaginally delivered. “Vaginal seeding” exposes C-section-delivered infants to the maternal vaginal microbiome directly after birth, partly replicating the microbial exposures they would have received during a vaginal delivery. Studies have shown that vaginal seeding at birth partially restores the infant microbiome towards that of a vaginally delivered infant. More recently, preliminary studies have shown a potential benefit of vaginal seeding on health outcomes. Here, we examine the evidence from observational studies and randomized controlled trials that have evaluated microbiome restoration after C-section, and we discuss new research assessing the potential impact of vaginal seeding on immune, metabolic, and neurodevelopmental outcomes and the underlying mechanisms. Collectively, we review the potential health benefits, safety risks, regulatory implications, and future directions for the use of vaginal seeding in infants delivered by C-section. Full article

The pathogenesis of obesity is complex and incompletely understood, with an underlying interplay between our genetic architecture and obesogenic environment. The public understanding of the development of obesity is shrouded in myths with widespread societal misconceptions. Body Mass Index (BMI) is a highly heritable trait. However, despite reports from recent genome-wide association studies, only a small proportion of the overall heritability of BMI is known to be lurking within the human genome. Other non-genetic heritable traits may contribute to BMI. The gut microbiome is an excellent candidate, implicating complex interlinks with hypothalamic control of appetite and metabolism via entero-endocrine, autonomic, and neuro-humeral pathways. The neonatal gut microbiome derived from the mother via transgenerational transmission (vaginal delivery and breastfeeding) tends to have a permanence within the gut. Conversely, non-maternally derived gut microbiota manifest mutability that responds to changes in lifestyle and diet. We should all strive to optimize our lifestyles and ensure a diet that is replete with varied and unprocessed plant-based foods to establish and nurture a healthy gut microbiome. Women of reproductive age should optimize their gut microbiome, particularly pre-conception, ante- and postnatally to enable the establishment of a healthy neonatal gut microbiome in their offspring. Finally, we should redouble our efforts to educate the populace on the pathogenesis of obesity, and the role of heritable (but modifiable) factors such as the gut microbiome. Such renewed understanding and insights would help to promote the widespread adoption of healthy lifestyles and diets, and facilitate a transition from our current dispassionate and stigmatized societal approach towards people living with obesity towards one that is epitomized by understanding, support, and compassion. Full article

Background/Objectives: In recent years, due to the emergence of antimicrobial resistance, probiotics have been increasingly used during pregnancy and lactation with real maternal–fetal benefits. Probiotic intervention, especially multi-strain probiotics, due to their anti-inflammatory, metabolic, and immunomodulatory actions, can be performed prophylactically and therapeutically with promising results regarding maternal, fetal, and neonatal health. The administration of probiotics can modulate the maternal microbiome, regulate microflora imbalance in various conditions (overweight/obesity, gestational diabetes mellitus (GDM), preeclampsia, allergic diseases), and influence several reactions such as modulating the non-specific cellular immune system, metabolic processes, and inhibition of pathogens. This study aimed to analyze, based on available data, how the administration of probiotic supplements to women during pregnancy can modify immunometabolic responses to microbial dysbiosis to limit weight gain and the risk of obesity, to improve glucose homeostasis and reduce the risk of GDM, to prevent preeclampsia and its effects on maternal–fetal outcomes, and to reduce rates of atopic eczema and allergic diseases in infants. Methods: We performed a systematic search in MEDLINE/PubMed to identify studies that have investigated the effects of probiotic intervention on the immunometabolic response in pregnancy and lactation, especially in women with diabetes, overweight/obesity, preeclampsia, and allergic conditions. Results: Fifty-six RCT studies, totaling 15,044 women, matched the inclusion criteria, of which eight were for interventions on the immune response, twenty on allergic conditions, seven on obesity and excess weight gain in pregnancy, and twenty-one on GDM. Conclusions: Due to the heterogeneous structure and the size of the samples, the methodologies, formulations, moment of initiation, and study durations, future research is needed to establish their effectiveness and safety in pregnancy and lactation regarding maternal-fetal health and outcomes in childhood and adult life. Full article

Background/Objectives: Infertility is a multifactorial condition influenced by various factors, including dysbiosis and alterations in the genital tract microbiome. Recent studies emphasize the microbiome’s significant role in influencing a woman’s fertility potential, thereby affecting the chances of spontaneous conception and the outcomes of assisted reproductive treatments. Understanding the microbial characteristics and unique features of a healthy genital microbiome, as well as how changes in its composition can impact fertility, would allow for a more comprehensive and personalized approach to managing assisted reproductive treatments. The microbiome also influences pregnancy outcomes, and restoring its balance has been shown to improve fertility in infertile couples. The human microbiome plays a key role in maintaining the body’s overall health. Disruptions in microbiome balance among women of reproductive age can contribute to a range of pregnancy-related complications, with notable consequences for both maternal and fetal well-being. Emerging research has highlighted a connection between the reproductive tract microbiome and outcomes of assisted reproductive technologies (ART), suggesting that re-establishing a healthy microbial environment may enhance fertility in couples facing infertility. Methods: We conducted a search on PubMed using the keywords “microbiome”, “infertility”, and “ART” over the past 10 years. This article aims to provide an updated overview of the role of the microbiome in female reproductive health, with a focus on its implications for fertility treatment. Results: The microbiome has a significant role in influencing women’s fertility. Conclusions: Understanding the microbiome’s impact on fertility and pregnancy outcomes may lead to more effective and personalized approaches in fertility treatments, improving the chances of successful conception and pregnancy. Full article