Probiotics for preventing gestational diabetes

Relationship between gut microbiota and the pathogenesis of gestational diabetes mellitus: a systematic review

Introduction

Gestational diabetes mellitus (GDM) is a form of gestational diabetes mellitus characterized by insulin resistance and abnormal function of pancreatic beta cells. In recent years, genomic association studies have revealed risk and susceptibility genes associated with genetic susceptibility to GDM. However, genetic predisposition cannot explain the rising global incidence of GDM, which may be related to the increased influence of environmental factors, especially the gut microbiome. Studies have shown that gut microbiota is closely related to the occurrence and development of GDM. This paper reviews the relationship between gut microbiota and the pathological mechanism of GDM, in order to better understand the role of gut microbiota in GDM, and to provide a theoretical basis for clinical application of gut microbiota in the treatment of related diseases.

Methods

The current research results on the interaction between GDM and gut microbiota were collected and analyzed through literature review. Keywords such as "GDM", "gut microbiota" and "insulin resistance" were used for literature search, and the methodology, findings and potential impact on the pathophysiology of GDM were systematically evaluated.

Results

It was found that the composition and diversity of gut microbiota were significantly associated with the occurrence and development of GDM. Specifically, the abundance of certain gut bacteria is associated with an increased risk of GDM, while other changes in the microbiome may be associated with improved insulin sensitivity. In addition, alterations in the gut microbiota may affect blood glucose control through a variety of mechanisms, including the production of short-chain fatty acids, activation of inflammatory pathways, and metabolism of the B vitamin group.

Discussion

The results of this paper highlight the importance of gut microbiota in the pathogenesis of GDM. The regulation of the gut microbiota may provide new directions for the treatment of GDM, including improving insulin sensitivity and blood sugar control through the use of probiotics and prebiotics. However, more research is needed to confirm the generality and exact mechanisms of these findings and to explore potential clinical applications of the gut microbiota in the management of gestational diabetes. In addition, future studies should consider the interaction between environmental and genetic factors and how together they affect the risk of GDM.

Accounting for the health risk of probiotics

Probiotics have long been associated with a myriad of health benefits, so much so that their adverse effects whether mild or severe, are often neglected or overshadowed by the enormous volume of articles describing their beneficial effects in the current literature. Recent evidence has demonstrated several health risks of probiotics that warrant serious reconsideration of their applications and further investigations. This review aims to highlight studies that report on how probiotics might cause opportunistic systemic and local infections, detrimental immunological effects, metabolic disturbance, allergic reactions, and facilitating the spread of antimicrobial resistance. To offer a recent account of the literature, articles within the last five years were prioritized. The narration of these evidence was based on the nature of the studies in the following order of preference: clinical studies or human samples, in vivo or animal models, in situ, in vitro and/or in silico. We hope that this review will inform consumers, food scientists, and medical practitioners, on the health risks, while also encouraging research that will focus on and clarify the adverse effects of probiotics.

The effects of prebiotic, probiotic or synbiotic supplementation on overweight/obesity indicators: an umbrella review of the trials' meta-analyses

Background

There is controversial data on the effects of prebiotic, probiotic, or synbiotic supplementations on overweight/obesity indicators. Thus, we aimed to clarify this role of biotics through an umbrella review of the trials' meta-analyses.

Methods

All meta-analyses of the clinical trials conducted on the impact of biotics on overweight/obesity indicators in general populations, pregnant women, and infants published until June 2023 in PubMed, Web of Sciences, Scopus, Embase, and Cochrane Library web databases included. The meta-analysis of observational and systematic review studies without meta-analysis were excluded. We reported the results by implementing the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) flowchart. The Assessment of Multiple Systematic Reviews-2 (AMSTAR2) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) systems were used to assess the methodological quality and quality of evidence.

Results

Overall, 97 meta-analysis studies were included. Most studies were conducted on the effect of probiotics in both genders. Consumption of prebiotic: 8-66 g/day, probiotic: 104 -1.35×1015 colony-forming unit (CFU)/day, and synbiotic: 106-1.5×1011 CFU/day and 0.5-300 g/day for 2 to 104 weeks showed a favorable effect on the overweight/obesity indicators. Moreover, an inverse association was observed between biotics consumption and overweight/obesity risk in adults in most of the studies. Biotics did not show any beneficial effect on weight and body mass index (BMI) in pregnant women by 6.6×105-1010 CFU/day of probiotics during 1-25 weeks and 1×109-112.5×109 CFU/capsule of synbiotics during 4-8 weeks. The effect of biotics on weight and BMI in infants is predominantly non-significant. Prebiotics and probiotics used in infancy were from 0.15 to 0.8 g/dL and 2×106-6×109 CFU/day for 2-24 weeks, respectively.

Conclusion

It seems biotics consumption can result in favorable impacts on some anthropometric indices of overweight/obesity (body weight, BMI, waist circumference) in the general population, without any significant effects on birth weight or weight gain during pregnancy and infancy. So, it is recommended to intake the biotics as complementary medications for reducing anthropometric indices of overweight/obese adults. However, more well-designed trials are needed to elucidate the anti-obesity effects of specific strains of probiotics.

Oral Probiotic Supplementation in Pregnancy to Reduce Group B Streptococcus Colonisation (OPSiP trial): study protocol for a double-blind parallel group randomised placebo trial

INTRODUCTION

Group B streptococcus (GBS), or Streptococcus agalactiae, remains a leading cause of neonatal morbidity and mortality. Canadian guidelines advise universal maternal screening for GBS colonisation in pregnancy in conjunction with selective antibiotic therapy. This results in over 1000 pregnant individuals receiving antibiotic therapy to prevent one case of early-onset neonatal GBS disease, and over 20 000 pregnant individuals receiving antibiotic therapy to prevent one neonatal death. Given the growing concern regarding the risk of negative sequela from antibiotic exposure, it is vital that alternative approaches to reduce maternal GBS colonisation are explored.Preliminary studies suggest some probiotic strains could confer protection in pregnancy against GBS colonisation.

METHODS AND ANALYSIS

This double-blind parallel group randomised trial aims to recruit 450 pregnant participants in Vancouver, BC, Canada and will compare GBS colonisation rates in those who have received a daily oral dose of three strains of probiotics with those who have received a placebo. The primary outcome will be GBS colonisation status, measured using a vaginal/rectal swab obtained between 35 weeks' gestation and delivery. Secondary outcomes will include maternal antibiotic exposure and urogenital infections. Analysis will be on an intention-to-treat basis.

PATIENT OR PUBLIC INVOLVEMENT

There was no patient or public involvement in the design of the study protocol.

ETHICS AND DISSEMINATION

This study protocol received ethics approval from the University of British Columbia's Clinical Research Ethics Board, Dublin City University and Health Canada. Findings will be presented at research rounds, conferences and in peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03407157.

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.

Cellular and molecular overview of gestational diabetes mellitus: Is it predictable and preventable?

BACKGROUND

In contrast to overt diabetes mellitus (DM), gestational DM (GDM) is defined as impaired glucose tolerance induced by pregnancy, which may arise from exaggerated physiologic changes in glucose metabolism. GDM prevalence is reported to be as high as 20% among pregnancies depending on the screening method, gestational age, and the population studied. Maternal and fetal effects of uncontrolled GDM include stillbirth, macrosomia, neonatal diabetes, birth trauma, and subsequent postpartum hemorrhage. Therefore, it is essential to find the potential target population and associated predictive and preventive measures for future intensive peripartum care.

AIM

To review studies that explored the cellular and molecular mechanisms of GDM as well as predictive measures and prevention strategies.

METHODS

The search was performed in the Medline and PubMed databases using the terms “gestational diabetes mellitus,” “overt diabetes mellitus,” and “insulin resistance.” In the literature, only full-text articles were considered for inclusion (237 articles). Furthermore, articles published before 1997 and duplicate articles were excluded. After a final review by two experts, all studies (1997-2023) included in the review met the search terms and search strategy (identification from the database, screening of the studies, selection of potential articles, and final inclusion).

RESULTS

Finally, a total of 79 articles were collected for review. Reported risk factors for GDM included maternal obesity or overweight, pre-existing DM, and polycystic ovary syndrome. The pathophysiology of GDM involves genetic variants responsible for insulin secretion and glycemic control, pancreatic β cell depletion or dysfunction, aggravated insulin resistance due to failure in the plasma membrane translocation of glucose transporter 4, and the effects of chronic, low-grade inflammation. Currently, many antepartum measurements including adipokines (leptin), body mass ratio (waist circumference and waist-to-hip ratio], and biomarkers (microRNA in extracellular vesicles) have been studied and confirmed to be useful markers for predicting GDM. For preventing GDM, physical activity and dietary approaches are effective interventions to control body weight, improve glycemic control, and reduce insulin resistance.

CONCLUSION

This review explored the possible factors that influence GDM and the underlying molecular and cellular mechanisms of GDM and provided predictive measures and prevention strategies based on results of clinical studies.

Effects of probiotics in patients with morbid obesity undergoing bariatric surgery: a systematic review and meta-analysis

BACKGROUND

Probiotics are commonly used after bariatric surgery. However, uncertainty remains regarding their effects. The purpose of this systematic review was to assess the effect of probiotics in patients with morbid obesity undergoing bariatric surgery.

METHODS

PubMed, Cochrane Library, Embase, Science Direct, and Web of Science were searched from inception to April 4, 2023. No language restrictions were applied. Relevant randomized controlled trials and controlled clinical trials were included. We used the aggregated data extracted from the trials and assessed the heterogeneity. When severe heterogeneity was detected, a random effect model was used. All stages of the review were done by independent authors.

RESULTS

We screened 2024 references and included 11 randomized controlled trials and controlled clinical trials. Compared with the protocol groups, probiotics showed significant effects on regulating aspartate amino transferase level (MD = -4.32 U/L; 95% CI [-7.10, -1.53], p = 0.002), triglycerides (MD = -20.16 mg/dL; 95% CI [-34.51, -5.82], p = 0.006), weight (MD = -1.99 kg; 95% CI [-3.97, -0.01], p = 0.05), vitamin B12 (MD = 2.24 pg/dL; 95% CI [-0.02, 4.51], p = 0.05), dietary energy (MD = -151.03 kcal; 95% CI [-215.68, -86.37], p < 0.00001), dietary protein (MD = -4.48 g/day, 95% CI [-8.76, -0.20], p = 0.04), dietary carbohydrate (MD = -34.25 g/day, 95% CI [-44.87, -23.62], p < 0.00001), and dietary fiber (MD = -2.17 g/day, 95% CI [-3.21, -1.14], p < 0.0001). There were no severe side effects related to probiotics.

CONCLUSIONS

Our meta-analysis suggested that probiotics may delay the progression of liver function injury, improve lipid metabolism, reduce weight, and reduce food intake, although the effects on other indicators were insignificant. Probiotics may be helpful for patients undergoing bariatric surgery. The review was registered on PROSPERO (International prospective register of systematic reviews): CRD42023407970. No primary source of funding.

Review article: Functional dyspepsia and pregnancy-Effects and management in a special population

BACKGROUND

Around 10% of Americans meet the Rome IV criteria for functional dyspepsia (FD), with a significantly higher rate in women. FD also has a higher prevalence in women below the age of 50, suggesting that women who are affected are likely to be of reproductive age. Unfortunately, there is a lack of research or evidence-based guidelines on managing FD in pregnancy.

AIMS AND METHODS

To address this issue, we aimed to perform a systematic review of the interactions between FD and pregnancy and managing pre-existing FD in the peripartum and post-partum phases using current lifestyle, pharmacological, non-pharmacological and alternative medicine interventions.

RESULTS

Due to the lack of Rome IV FD-specific data in pregnancy, we instead performed a narrative review on how existing FD interventions could be extrapolated to the pregnant population. Where possible we use the highest level of available evidence or official guidelines to answer these questions, which often involves synthesising treatment and safety evidence of these interventions in other diseases during pregnancy. Finally, we highlight current substantial knowledge gaps requiring further research for the safe management of a pregnant patient with pre-existing FD.

CONCLUSIONS

Overall, despite the paucity of knowledge of treating FD during pregnancy, providers can mitigate this uncertainty by planning ahead with the patient. Patients should ideally minimise treatment until after breastfeeding. However, interdisciplinary resources are available to ensure that minimal-risk interventions are maximised, while interventions with more risks, if necessary, are justifiable by both the patient and the care team. Future investigations should continue to elicit the mechanistic relationship between FD and pregnancy while cautiously expanding prospective research on promising and safe therapies in pregnant patients with pre-existing FD.

Lacticaseibacillus rhamnosus CA15 (DSM 33960) strain as a new driver in restoring the normal vaginal microbiota: A randomized, double-blind, placebo-controlled clinical trial

Probiotics play a key role in maintaining the health of the female reproductive tract, representing a promising alternative to safeguard or restore the homeostasis of the vaginal microbiota. The present randomized double-blind placebo-controlled study was performed to evaluate the ability of the potential probiotic Lacticaseibacillus rhamnosus CA15 (DSM 33960) strain, orally administrated, to balance the vaginal microbiota of women with vaginal dysbiosis. Sixty women, with signs and symptoms of vaginal dysbiosis, were recruited and randomly allocated to receive oral capsules containing the L. rhamnosus CA15 (DSM 33960) strain at 1.0 × 10¹⁰ colony-forming units or placebo once daily for 10 days. Clinical and microbiological parameters were evaluated in three scheduled appointments: at baseline (T0), 10 days after the start of the treatment (T1), and 30 days after the end of the treatment (T2). In addition, the quality of life, through the WHO quality of life assessment questionnaire, was assessed at baseline (T0) and 30 days after the end of the treatment (T2). The probiotic was well tolerated and no side effects were reported. The oral consumption of the potential probiotic L. rhamnosus CA15 (DSM 33960) strain determined a significant improvement of both clinical signs and symptoms not only 10 days after the start of the treatment (T1) but also 30 days after the end of the treatment (T2). A significant reduction of potential pathogens and a concomitant increase of lactobacilli was revealed, by microbial count, at both T1 and T2 sampling times. In addition, the enhancement of the perceived physical health, social relations, and environment was reported. Differently, in placebo group clinical and microbiological parameters as well as quality of life remained almost unchanged. The potential probiotic L. rhamnosus CA15 (DSM 33960) strain could be a safe and effective approach to restore and maintain a balanced vaginal microbiota.

Emerging issues in probiotic safety: 2023 perspectives

Probiotics are used for both generally healthy consumers and in clinical settings. However, theoretical and proven adverse events from probiotic consumption exist. New probiotic strains and products, as well as expanding use of probiotics into vulnerable populations, warrants concise, and actionable recommendations on how to work toward their safe and effective use. The International Scientific Association for Probiotics and Prebiotics convened a meeting to discuss and produce evidence-based recommendations on potential acute and long-term risks, risks to vulnerable populations, the importance for probiotic product quality to match the needs of vulnerable populations, and the need for adverse event reporting related to probiotic use. The importance of whole genome sequencing, which enables determination of virulence, toxin, and antibiotic resistance genes, as well as clear assignment of species and strain identity, is emphasized. We present recommendations to guide the scientific and medical community on judging probiotic safety.

Probiotics for preventing gestational diabetes in overweight or obese pregnant women: A review

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit to the host. Specific probiotics or probiotic foods can be used to reduce the risk of diseases associated with aberrant gut microbiota composition. The incidence of gestational diabetes mellitus (GDM) has increased annually with the proportion of overweight and obese people. Overweight or obese pregnant women are at high risk of GDM and have obvious changes in gut microbiota compared with normal-weight pregnant women. Specific probiotics or probiotic foods may alter gut microbiota in overweight or obese pregnant women and inhibit the expression of inflammatory factors, consequently resulting in weight loss and reduced insulin resistance. This review discusses the mechanism of probiotics on GDM, as well as the dose, method and duration of probiotics use, and summarizes current evidence on probiotics in improving glucose metabolism and other maternal and infant outcomes in overweight/obese pregnant women.

Bifidobacterium lactis Probio-M8 ameliorated the symptoms of type 2 diabetes mellitus mice by changing ileum FXR-CYP7A1

The aim of this study was to investigate the effect of Bifidobacterium lactis Probio-M8 on glucolipid metabolism and gut microbiota (GM) composition in type 2 diabetes mellitus (T2DM) mice. The glucolipid metabolic profiles were analyzed. The 16S rRNA gene sequencing was employed to investigate GM. The levels of farnesyl X receptor (FXR) and cytochrome p450 7A1 (CYP7A1) were detected by quantitative polymerase chain reaction and western blot assays. The total bile acids (TBAs), ceramide (CE), glucagon-like peptide-1 (GLP-1), and fibroblast growth factor (FGF)-15 were also detected. The morphological features of liver and pancreas were also analyzed. Compared with the model group, Probio-M8 restored body weight, food intake and water intake, as well as improved hyperglycemia symptoms, serum glucolipid parameters, and the composition of intestinal microbes in T2DM diabetic mice. Moreover, the reduced level of FXR and the increased level of CYP7A1 in T2DM mice were reversed by Probio-M8 treatment. The increased levels of TBA and CE and the reduced levels of GLP-1 and FGF-15 in T2DM mice were altered after Probio-M8 stimulation. Besides, the altered morphology of liver and ileum in T2DM mice was alleviated by Probio-M8 treatment. Taken together, we suggested that the symptoms of T2DM could be ameliorated by Probio-M8 in T2DM mice.

The effect of probiotic and synbiotic use on glycemic control in women with gestational diabetes: A systematic review and meta-analysis

AIMS

To investigate the impact of probiotic/synbiotic use on glycemic control in women with gestational diabetes.

METHODS

We searched the PubMed, Medline, Scopus, ScienceDirect, Web of Science, Cochrane Central Register of Controlled Trials, Dergipark, and Council of Higher Education Thesis Center databases through March 2022. Screening was performed according to the population, intervention, comparison, outcome and study type. This systematic review and meta-analysis were performed in accordance with the Preferred Reporting Items for Systematic Review and meta-analyses (PRISMA-2020) statement.

RESULTS

Eight RCTs involving 551 patients were included in the meta-analysis. Probiotic use in women with gestational diabetes significantly decreased fasting blood glucose (mean difference: -1.43; 95 % CI: -2.78 to -0.09, p: 0.04) and serum insulin (mean difference: -3.66; 95 % CI: -5.04 to -2.27, p < 0.001). Moreover, the use of probiotics and synbiotics significantly reduced the HOMA-IR level compared to the control group (probiotic group: mean difference: -0.74; 95 % CI: -1.05 to -0.44, p < 0.001; synbiotic group: mean difference: -0.68; 95 % CI: -1.26 to -0.09, p: 0.02).

CONCLUSIONS

The use of probiotics in women with GDM reduced fasting plasma glucose, fasting serum insulin, and HOMA-IR levels. In addition, the use of synbiotics decreased HOMA-IR. Probiotic/synbiotic use is promising as a potential therapy to assist in glycemic control in gestational diabetes. Further high-quality studies are required to determine their safety.

Vitamin B12 status and folic acid/vitamin B12 related to the risk of gestational diabetes mellitus in pregnancy: a systematic review and meta-analysis of observational studies

Background

This review was conducted to investigate the association between serum vitamin B12 levels as well as folic acid/vitamin B12 during pregnancy and the risk of gestational diabetes mellitus (GDM).

Methods

A comprehensive search of electronic databases (Embase, PubMed, and Web of Science) was performed. The odds ratios (ORs) with 95% confidence intervals (CIs) of GDM risk were summarized using a random effects model. We also performed subgroup analyses to explore the source of heterogeneity.

Results

A total of 10 studies, including 10,595 pregnant women were assessed. Women with vitamin B12 deficiency were at higher risk for developing GDM when compared with those who were vitamin B12 sufficient (OR, 1.46; 95% CI 1.21–1.79; I²: 59.0%). Subgroup analysis indicated that this association might differ based on sample size and geographical distribution. Elevated vitamin B12 levels may decrease the risk of GDM by 23%. The role of excess folic acid and low vitamin B12 levels in the occurrence of GDM is also controversial.

Conclusion

In summary, vitamin B12 deficiency is associated with increased risk of GDM, it is necessary to pay more attention to the balance of vitamin B12 and folic acid. However, more in-depth studies across multiple populations are needed to verify these results.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04911-9.

Gastrointestinal Microbiome and Multiple Health Outcomes: Umbrella Review

In recent years, there has been growing concern about the impact of the gastrointestinal microbiome on human health outcomes. To clarify the evidence for a link between the gastrointestinal microbiome and a variety of health outcomes in humans, we conducted an all-encompassing review of meta-analyses and systematic reviews that included 195 meta-analyses containing 950 unique health outcomes. The gastrointestinal microbiome is related to mortality, gastrointestinal disease, immune and metabolic outcomes, neurological and psychiatric outcomes, maternal and infant outcomes, and other outcomes. Existing interventions for intestinal microbiota (such as probiotics, fecal microbiota transplant, etc.) are generally safe and beneficial to a variety of human health outcomes, but the quality of evidence is not high, and more detailed and well-designed randomized controlled trials are necessary.

Probiotic Intervention in the Treatment of Diabetes Mellitus: A Review

Diabetes is a noncommunicable lifestyle condition that impacts millions of individuals worldwide. Diabetes is a physiological illness that affects several different organs in the human body. Several studies have found a direct relationship between gut microbiota and diabetes control. Probiotic intervention in the treatment of diabetes mellitus has been the center of focus in the current scenario. Alteration in composition and metabolic activity of gut microbiota significantly contributes to human health. However, the key mechanism of gut microbiota in the inhibition of diabetes is not fully understood. This review discusses the effect of probiotics on diabetes and the role of gut microbiota. It emphasizes on the pharmacological effects of probiotics on diabetic symptoms like glycemic response, hypercholesterolemia, hypertension, as well as gestational diabetes.

Effects of Probiotic Supplementation during Pregnancy on the Future Maternal Risk of Metabolic Syndrome

Probiotics are live microorganisms that induce health benefits in the host. Taking probiotics is generally safe and well tolerated by pregnant women and their children. Consumption of probiotics can result in both prophylactic and therapeutic effects. In healthy adult humans, the gut microbiome is stable at the level of the dominant taxa: Bacteroidetes, Firmicutes and Actinobacteria, and has a higher presence of Verrucomicrobia. During pregnancy, an increase in the number of Proteobacteria and Actinobacteria phyla and a decrease in the beneficial species Roseburia intestinalis and Faecalibacterium prausnitzii are observed. Pregnancy is a "window" to the mother's future health. The aim of this paper is to review studies assessing the potentially beneficial effects of probiotics in preventing the development of diseases that appear during pregnancy, which are currently considered as risk factors for the development of metabolic syndrome, and consequently, reducing the risk of developing maternal metabolic syndrome in the future. The use of probiotics in gestational diabetes mellitus, preeclampsia and excessive gestational weight gain is reviewed. Probiotics are a relatively new intervention that can prevent the development of these disorders during pregnancy, and thus, would reduce the risk of metabolic syndrome resulting from these disorders in the mother's future.

Inositol Nutritional Supplementation for the Prevention of Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This study was aimed at assessing the efficacy and safety of inositol nutritional supplementation during pregnancy for the prevention of GDM. PubMed, Embase, MEDLINE, and Cochrane library were systematically searched for randomized controlled trails (RCTs) in this field until May 2022. Primary outcomes were the incidence for GDM and plasma glucose levels by oral glucose tolerance test (OGTT). Pooled results were expressed as relative risk (RR) or mean difference (MD) with a 95% confidence interval (95% CI). Seven RCTs with 1321 participants were included in this study. Compared with the control group, 4 g myo-inositol (MI) supplementation per day significantly decreased the incidence of GDM (RR = 0.30, 95% CI (0.18, 0.49), p < 0.00001). It significantly decreased the plasma glucose levels of OGTT regarding fasting-glucose OGTT (MD = −4.20, 95% CI (−5.87, −2.54), p < 0.00001), 1-h OGTT (MD = −8.75, 95% CI (−12.42, −5.08), p < 0.00001), and 2-h OGTT (MD = −8.59, 95% CI (−11.81, −5.83), p < 0.00001). It also decreased the need of insulin treatment, and reduced the incidence of preterm delivery and neonatal hypoglycemia. However, no difference was observed between 1.1 g MI per day plus 27.6 mg D-chiro-inositol (DCI) per day and the control group regarding all evaluated results. In conclusion, 4 g MI nutritional supplementation per day during early pregnancy may reduce GDM incidence and severity, therefore may be a practical and safe approach for the prevention of GDM.

Efficacy of Direct or Indirect Use of Probiotics for the Improvement of Maternal Depression during Pregnancy and in the Postnatal Period: A Systematic Review and Meta-Analysis

The mother and infant form a unique bond, with maternal mental health affecting the interactions with the infant and infant behaviours impacting maternal mental health. One of the possible mechanisms influencing maternal mental health is the manipulation of the gut-brain axis by consuming probiotic supplements. Probiotics can also have an indirect influence on maternal mental health via the modulation of the infant microbiome and consequently improving the infant’s health and thus, indirectly leading to an improvement in maternal mood. This systematic review evaluated the efficacy of probiotics on maternal mental health by searching for randomised controlled trials via international databases: Cochrane Library, PubMed, Scopus, ScienceDirect, and Web of Science until January 2022. A meta-analysis was performed using the Cochrane Collaboration methodology where possible. We found seven clinical trials that included the word probiotics and addressed maternal depression and/or anxiety. Of these, five trials investigated the influence of maternal probiotic supplementation on the gut-brain axis. Two trials investigated the indirect influence of probiotics on maternal depression via supplementation of probiotics by infants and subsequent influence on the crying of colicky infants. Meta-analysis of two studies of pregnant and postnatal women and two studies of infants consuming probiotics on the outcome of the Edinburgh Postnatal Depression Scale for mothers showed no statistical difference. The findings indicate that maternal depression is very complex and is influenced by various bidirectional factors. One of the factors that can improve maternal mental health is probiotics, however, careful consideration must be given to correct strain selection as strain-specific effectiveness was observed. Further well-designed, robust clinical studies are warranted.

The intestine and the microbiota in maternal glucose homeostasis during pregnancy

It is now well established that, beyond its role in nutrient processing and absorption, the intestine and its accompanying gut microbiome constitute a major site of immunological and endocrine regulation that mediates whole-body metabolism. Despite the growing field of host-microbe research, few studies explore what mechanisms govern this relationship in the context of pregnancy. During pregnancy, significant maternal metabolic adaptations are made to accommodate the additional energy demands of the developing fetus and to prevent adverse pregnancy outcomes. Recent data suggest that the maternal gut microbiota may play a role in these adaptations, but changes to maternal gut physiology and the underlying intestinal mechanisms remain unclear. In this review, we discuss selective aspects of intestinal physiology including the role of the incretin hormone, glucagon-like peptide 1 (GLP-1), and the role of the maternal gut microbiome in the maternal metabolic adaptations to pregnancy. Specifically, we discuss how bacterial components and metabolites could mediate the effects of the microbiota on host physiology, including nutrient absorption and GLP-1 secretion and action, and whether these mechanisms may change maternal insulin sensitivity and secretion during pregnancy. Finally, we discuss how these pathways could be altered in disease states during pregnancy including maternal obesity and diabetes.

Gestational Diabetes, Colorectal Cancer, Bariatric Surgery, and Weight Loss among Diabetes Mellitus Patients: A Mini Review of the Interplay of Multispecies Probiotics

Diabetes mellitus has been steadily increasing over the past decades and is one of the most significant global public health concerns. Diabetes mellitus patients have an increased risk of both surgical and post-surgical complications. The post-surgical risks are associated with the primary condition that led to surgery and the hyperglycaemia per se. Gut microbiota seems to contribute to glucose homeostasis and insulin resistance. It affects the metabolism through body weight and energy homeostasis, integrating the peripheral and central food intake regulatory signals. Homeostasis of gut microbiota seems to be enhanced by probiotics pre and postoperatively. The term probiotics is used to describe some species of live microorganisms that, when administered in adequate amounts, confer health benefits on the host. The role of probiotics in intestinal or microbial skin balance after abdominal or soft tissue elective surgeries on DM patients seems beneficial, as it promotes anti-inflammatory cytokine production while increasing the wound-healing process. This review article aims to present the interrelation of probiotic supplements with DM patients undergoing elective surgeries.