Preventive effect of probiotics supplementation on occurrence of gestational diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

ILSI Europe perspective review: site-specific microbiota changes during pregnancy associated with biological consequences and clinical outcomes: opportunities for probiotic interventions

Pregnancy induces notable alterations in the gut, vaginal, and oral microbiota driven by hormonal, immune, metabolic, dietary, and environmental factors. During pregnancy, the gut microbiota is characterized by increased proportions of the genus Bifidobacterium and the phyla Pseudomonadota (formerly Proteobacteria) and Actinomycetota (formerly Actinobacteria). These changes occur alongside reduced alpha diversity and greater beta diversity, changes that influence maternal metabolism and fetal development. Shifts in gut and oral microbiota have been associated with complications such as preterm birth (PTB), pre-eclampsia, and gestational diabetes (GDM), though patterns are sometimes inconsistent. The vaginal microbiota remains Lactobacillus-dominant during pregnancy, with reduced diversity leading to reduced risk of pathogenic infection and increased diversity has been linked with a higher risk of PTB. Hormonal changes also affect the oral microbiota, potentially increasing pathogenic species and contributing to adverse outcomes like PTB. Probiotic supplementation during pregnancy has significant potential to reduce adverse pregnancy outcomes; however, clinical studies are still limited. Probiotics may be effective in alleviating maternal constipation and lead to lower PTB risk, particularly by modulating the vaginal microbiota, but they have limited impact on GDM. In the context of maternal mental health, some studies suggest benefits of probiotics in reducing anxiety, but effects on depression are inconclusive. This perspective examines how pregnancy-related microbial shifts, both natural and probiotic-induced, affect maternal and fetal health and highlights potential opportunities for the innovative use of probiotics during the gestation period.

Effects of Bioconverted Guava Leaf (Psidium guajava L.) Extract on Skeletal Muscle Damage by Regulation of Ubiquitin-Proteasome System and Apoptosis in Type 2 Diabetic Mice

Skeletal muscle atrophy is one of the serious complications of diabetes, which increases the risk of frailty, falls, and mortality. However, interventions for muscle atrophy are limited, and research is needed regarding the treatment of muscle wasting. Recently, the bioconversion of natural products by lactic acid bacteria has been highlighted as a possibility to improve the bioavailability of active ingredients. This process also produces metabolites, which are key signaling mediators for a variety of physiological functions. This study investigated the effect of bioconverted guava leaf (Psidium guajava L., GL) by Lactobacillus plantarum on hyperglycemia-induced skeletal muscle atrophy in type 2 diabetes mellites (T2DM) mice. Diabetes was induced by a high-fat diet with a two-time streptozotocin (STZ) injection (60 mg/kg BW) in male C57BL/6J mice. After diabetes was induced (a fasting blood glucose level (FBG) ≥ 300 mg/dL), the mice were administered with GL (100 mg/kg/day) or bioconverted GL (FGL) (50 mg/kg/day) by oral gavage for 14 weeks. FGL contains different substances such as hydroxyl-isocaproic acid and hydroxyl-isovaleric acid compared to GLE itself, which have potential to prevent muscle degradation in T2DM mice. GL and FGL supplementation reduced the FBG level in T2DM mice. In addition, GL and FGL supplementation enhanced muscle strength, the skeletal muscle cross-sectional area, and ameliorated ubiquitin-proteasome system (UPS)-related pathways in T2DM mice. On the other hand, GLE supplementation ameliorated glucose tolerance demonstrated by oral glucose tolerance test and enhanced insulin signaling pathway. In addition, only FGL supplementation attenuated skeletal muscle inflammation and apoptosis with an improved mammalian target of the rapamycin (mTOR)-autophagy-related pathway. Although administered at a half dose of GLE, FGL demonstrated greater efficacy in regulating the expression of these molecular markers. The result suggests that even GL itself has anti-diabetic effects, and the functionality would be enhanced by the bioconversion of GL with L. Plantarum, which has an additive or/and a synergistic effect. Taken together, FGL could be used as a potential nutraceutical to attenuate muscle degradation by the inhibition of inflammation, the UPS, and the apoptosis pathway.

Probiotic Supplementation during Pregnancy: Evaluating the Current Clinical Evidence against Gestational Diabetes Mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) constitutes a common metabolic disorder that could lead to deleterious short- and long-term complications in both the mother and her infant. Probiotic supplementation seems to exert diverse, healthy effects by acting as a preventive agent against various human diseases, including GDM.

OBJECTIVE

The purpose of the current narrative review was to critically summarize and scrutinize the available clinical studies during the last 15 years (2008-2023) concerning the use of probiotic supplementation during pregnancy as a protecting agent against GDM.

METHODS

A thorough and in-depth search was performed in the most accurate scientific databases, e.g., PubMed., Scopus, Web of Science, and Google Scholar applying effective, and relevant keywords.

RESULTS

There are currently some clinical studies suggesting the potential beneficial impact of probiotic supplementation in the prevention and/or co-treatment of GDM. Nevertheless, there is a high heterogeneity amongst the available clinical studies concerning the dosage, the administration duration, the probiotic species types, the method designs and protocols, and the study populations.

CONCLUSION

Probiotic supplementation at conventional dosages and in combination with a balanced healthy diet, and lifestyle seems to reduce the the risk of developing GDM, while ameliorating the severity of its symptoms. Further clinical studies taking into account the above considerations should be performed to establish conclusive results, while the future meta-analyses should include studies with the feasibly lowest heterogeneity.

Decoding the Gut Microbiota-Gestational Diabetes Link: Insights from the Last Seven Years

The human microbiome, a complex ecosystem of bacteria, viruses, and protozoans living in symbiosis with the host, plays a crucial role in human health, influencing everything from metabolism to immune function. Dysbiosis, or an imbalance in this ecosystem, has been linked to various health issues, including diabetes and gestational diabetes (GD). In diabetes, dysbiosis affects the function of adipose tissue, leading to the release of adipokines and cytokines, which increase inflammation and insulin resistance. During pregnancy, changes to the microbiome can exacerbate glucose intolerance, a common feature of GD. Over the past years, burgeoning insights into the gut microbiota have unveiled its pivotal role in human health. This article comprehensively reviews literature from the last seven years, highlighting the association between gut microbiota dysbiosis and GD, as well as the metabolism of antidiabetic drugs and the potential influences of diet and probiotics. The underlying pathophysiological mechanisms discussed include the impact of dysbiosis on systemic inflammation and the interplay with genetic and environmental factors. By focusing on recent studies, the importance of considering microbial health in the prevention and treatment of GD is emphasized, providing insights into future research directions and clinical applications to improve maternal-infant health outcomes.

Maternal gut microbiota in the health of mothers and offspring: from the perspective of immunology

Due to the physiological alteration during pregnancy, maternal gut microbiota changes following the metabolic processes. Recent studies have revealed that maternal gut microbiota is closely associated with the immune microenvironment in utero during pregnancy and plays a vital role in specific pregnancy complications, including preeclampsia, gestational diabetes, preterm birth and recurrent miscarriages. Some other evidence has also shown that aberrant maternal gut microbiota increases the risk of various diseases in the offspring, such as allergic and neurodevelopmental disorders, through the immune alignment between mother and fetus and the possible intrauterine microbiota. Probiotics and the high-fiber diet are effective inventions to prevent mothers and fetuses from diseases. In this review, we summarize the role of maternal gut microbiota in the development of pregnancy complications and the health condition of future generations from the perspective of immunology, which may provide new therapeutic strategies for the health management of mothers and offspring.

Interventions in preconception and pregnant women at risk of gestational diabetes; a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Women at risk of gestational diabetes mellitus (GDM) need preventative interventions.

OBJECTIVE

To evaluate targeted interventions before and during pregnancy for women identified as being at risk of developing GDM.

METHODS

Systematic review and meta-analysis conducted following PRISMA guidelines. MEDLINE, EMBASE and the Cochrane Library in addition to reference and citation lists were searched to identify eligible randomised controlled trials (RCTs) utilising risk stratification during the preconception period or in the first/early second trimester. Screening and data extraction were carried out by the authors independently. Quality assessment was conducted based on the Cochrane risk-of-bias tool. Random effects meta-analysis and narrative synthesis were performed.

RESULTS

Eighty-four RCTs were included: two during preconception and 82 in pregnancy, with a pooled sample of 22,568 women. Interventions were behavioural (n = 54), dietary supplementation (n = 19) and pharmacological (n = 11). Predictive factors for risk assessment varied; only one study utilised a validated prediction model. Gestational diabetes was reduced in diet and physical activity interventions (risk difference - 0.03, 95% CI 0.06, - 0.01; I2 58.69%), inositol (risk difference - 0.19, 95% CI 0.33, - 0.06; I2 92.19%), and vitamin D supplements (risk difference - 0.16, 95% CI 0.25, - 0.06; I2 32.27%). Subgroup analysis showed that diet and physical activity interventions were beneficial in women with ≥ 2 GDM risk factors (risk difference - 0.16, 95% CI 0.25, - 0.07; I2 11.23%) while inositol supplementation was effective in women with overweight or obesity (risk difference - 0.17, 95% CI 0.22, - 0.11; I2 0.01%). Effectiveness of all other interventions were not statistically significant.

CONCLUSIONS

This review provides evidence that interventions targeted at women at risk of GDM may be an effective strategy for prevention. Further studies using validated prediction tools or multiple risk factors to target high-risk women for intervention before and during pregnancy are warranted.

Shaping Microbiota During the First 1000 Days of Life

Given that the host-microbe interaction is shaped by the immune system response, it is important to understand the key immune system-microbiota relationship during the period from conception to the first years of life. The present work summarizes the available evidence concerning human reproductive microbiota, and also, the microbial colonization during early life, focusing on the potential impact on infant development and health outcomes. Furthermore, we conclude that some dietary strategies including specific probiotics and other-biotics could become potentially valuable tools to modulate the maternal-neonatal microbiota during this early critical window of opportunity for targeted health outcomes throughout the entire lifespan.