The Effects of Probiotic Supplements on Blood Markers of Endotoxin and Lipid Peroxidation in Patients Undergoing Gastric Bypass Surgery; a Randomized, Double-Blind, Placebo-Controlled, Clinical Trial with 13 Months Follow-Up

Exploring the interaction and impact of probiotic and commensal bacteria on vitamins, minerals and short chain fatty acids metabolism

There is increasing evidence that probiotic and commensal bacteria play a role in substrate metabolism, energy harvesting and intestinal homeostasis, and may exert immunomodulatory activities on human health. In addition, recent research suggests that these microorganisms interact with vitamins and minerals, promoting intestinal and metabolic well-being while producing vital microbial metabolites such as short-chain fatty acids (SCFAs). In this regard, there is a flourishing field exploring the intricate dynamics between vitamins, minerals, SCFAs, and commensal/probiotic interactions. In this review, we summarize some of the major hypotheses beyond the mechanisms by which commensals/probiotics impact gut health and their additional effects on the absorption and metabolism of vitamins, minerals, and SCFAs. Our analysis includes comprehensive review of existing evidence from preclinical and clinical studies, with particular focus on the potential interaction between commensals/probiotics and micronutrients. Finally, we highlight knowledge gaps and outline directions for future research in this evolving field.

Effect of time restricted feeding on anthropometric measures, eating behavior, stress, serum levels of BDNF and LBP in overweight/obese women with food addiction: a randomized clinical trial

BACKGROUND & AIM

Food addiction (FA) as a specific food-related behavior may play an essential role in the pathogenesis of obesity. Brain-derived neurotrophic factor (BDNF) and gut microbiota (GM) alterations probably through fasting are closely related to brain function, affecting eating behaviors and body weight management. This study aimed to evaluate the effect of time-restricted feeding (TRF) on serum BDNF levels and eating behaviors in overweight and obese women with FA.

METHODS AND DESIGN

This clinical trial was performed with a 2-month follow-up on 56 obese and overweight women with FA. Participants were randomly divided into two groups receiving a low-calorie diet (n = 27) and a group receiving a low-calorie diet with TRF (n = 29). Anthropometric measurements, biochemical markers, eating behavior, and stress were assessed during the study period.

RESULTS

The reductions in weight, body mass index (BMI), waist circumference, and body fat mass were significantly higher in the TRF group compared to the control group at week 8 (P = 0.018, P = 0.015. P = 0.03, and P = 0.036, respectively). The cognitive restriction score was higher in the TRF as compared with the control group (P = 0.002). The food addiction criteria score was significantly reduced in both groups (P < 0.001). Serum levels of BDNF were significantly increased in the TRF group (P < 0.001). In addition, BDNF levels had a positive and significant correlation with the cognitive restriction score (r = 0.468 and P < 0.001), While the correlation with FA was not significant (β = 0.588 and P = 0.618). Lipopolysaccharide binding protein decreased significantly in both groups, but this decrease was significantly higher in the TRF group than in the control group (P < 0.001).

CONCLUSION

The results of this study showed that a low-calorie diet with TRF is more effective in weight management than a low-calorie diet alone, probably through further modulating the GM and improving BDNF levels. More effective weight loss in the TRF is probably related to better management of eating behavior than FA.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials identifier: IRCT20131228015968N7.

Multidisciplinary combined treatment based on bariatric surgery for metabolic syndrome: a review article

As a chronic, multifactorial disease, obesity is associated with a global social and economic burden. This condition significantly affects normal daily life and healthy social interactions, and shortens the life expectancy of patients. Compared with traditional weight-loss methods, the emergence of bariatric surgery has effectively improved the management of obesity. Furthermore, bariatric surgery can also inhibit the progression of multiple metabolic diseases. Despite its potential advantages, bariatric surgery cannot completely eliminate the possibility of weight regain and inadequate weight loss following the procedure. For super-obese patients, bariatric surgery still remains a surgical risk. In addition, the psychological problems and poor eating habits of obese patients also affect the weight loss effect and daily life. Thus, various adjuvant therapies involving multiple disciplines have attracted people's attention. Recently, it has been recognized that the combination of multiple interventions based on bariatric surgery is more advantageous than a single intervention in alleviating the complex and diverse metabolic diseases associated with obesity. The combined therapy considerably enhances the long-term efficacy of bariatric surgery and plays a positive role in the mental health and social lives of patients. In this article, the authors review this multidisciplinary combination therapy to enhance the current understanding of the treatment of obesity.

Effect of Probiotic Supplementation on Intestinal Permeability in Overweight and Obesity: A Systematic Review of Randomized Controlled Trials and Animal Studies

Overweight and obesity are associated with increased intestinal permeability, characterized by loss of gut epithelial integrity, resulting in unregulated passage of lipopolysaccharide (LPS) and other inflammatory triggers into circulation, i.e., metabolic endotoxemia. In obesity, shifts in the gut microbiome negatively impact intestinal permeability. Probiotics are an intervention that can target the gut microbiome by introducing beneficial microbial species, potentially restoring gut barrier integrity. Currently, the role of probiotic supplementation in ameliorating obesity- and overweight-associated increases in gut permeability has not been reviewed. This systematic review aimed to summarize findings from both animal and clinical studies that evaluated the effect of probiotic supplementation on obesity-induced impairment in intestinal permeability (International Prospective Register of Systematic Reviews, CRD42022363538). A literature search was conducted using PubMed (Medline), Web of Science, and CAB Direct from origin until August 2023 using keywords of intestinal permeability, overweight or obesity, and probiotic supplementation. Of 920 records, 26 eligible records were included, comprising 12 animal and 14 clinical studies. Clinical trials ranged from 3 to 26 wk and were mostly parallel-arm (n = 13) or crossover (n = 1) design. In both animal and clinical studies, plasma/serum LPS was the most common measure of intestinal permeability. Eleven of 12 animal studies reported a positive effect of probiotic supplementation in reducing intestinal permeability. However, results from clinical trials were inconsistent, with half reporting reductions in serum LPS and half reporting no differences after probiotic supplementation. Bifidobacterium, Lactobacillus, and Akkermansia emerged as the most common genera in probiotic formulations among the animal and clinical studies that yielded positive results, suggesting that specific bacteria may be more effective at reducing intestinal permeability and improving gut barrier function. However, better standardization of strain use, dosage, duration, and the delivery matrix is needed to fully understand the probiotic impact on intestinal permeability in individuals with overweight and obesity.

Does gut microbiota affect the success of weight loss? Evidence and speculation

Obesity is a chronic state of excessive fat accumulation in the body, characterized by significant relapse and complicated by a range of health consequences. In the treatment of obesity, a holistic approach including diet, physical activity, pharmacotherapy, bariatric surgery, and psychological support is recommended. The implications of gut microbiota (GM) as a pathogenic factor in excess body weight have been discussed, and microbial-targeted therapies-including probiotics, prebiotics, and synbiotics-are considered adjuvant in obesity management. Many studies have focused on assessing the effectiveness of probiotics, prebiotics, or synbiotics in weight control, although with inconclusive results, mainly because of the significant heterogeneity of the studies (with different strains, doses, forms, interventional durations, and outcomes). It is also unclear whether using probiotics or synbiotics accompanied by weight loss dietary interventions or as a part of bariatric surgery will be more effective in obesity management, not only in the short-term but also for long-term weight loss maintenance. The aim of this study was to collect and compare the available scientific data on the effectiveness of probiotic or synbiotic supplementation (as a single therapy versus as part of dietary interventions, pharmacotherapy, or bariatric therapy) on weight control in obesity.

The gut microbiome in the fight against obesity: The potential of dietary factors

Obesity as a global public health burden has experienced a drastic growing trend recently. The management of obesity is challenging because of its complex etiology, and various factors are involved in its development, such as genetic and environmental factors. Different approaches are available to treat and/or manage obesity, including diet, physical activity, lifestyle changes, medications, and surgery. However, some of these approaches have inherent limitations and are closely associated with adverse effects. Therefore, probing into a novel/safe approach to treat and/or manage obesity is of fundamental importance. One such approach gaining renewed interest is the potential role of gut microbiota in obesity and its effectiveness in treating this condition. However, there is a dearth of comprehensive compilation of data on the potential role of the gut microbiome in obesity, particularly regarding dietary factors as a therapeutic approach. Therefore, this review aims to provide an updated overview of the role of gut microbiota in obesity, further highlighting the importance of dietary factors, particularly diet, prebiotics, and probiotics, as potential complementary and/or alternative therapeutic options. Moreover, the association of gut microbiota with obese or lean individuals has also been discussed.

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.

Effects of probiotic and magnesium co-supplementation on mood, cognition, intestinal barrier function and inflammation in individuals with obesity and depressed mood: A randomized, double-blind placebo-controlled clinical trial

Background

The co-occurrence of obesity and mood impairments named as “metabolic mood syndrome” (MMS) is often neglected in the obesity management. This study aimed to evaluate effects of Probio-Tec ^®BG-VCap-6.5 and magnesium co-supplementation on mood, cognition, intestinal barrier function and serum C reactive protein (CRP) levels in participants with obesity and depressed mood.

Design

Seventy-four eligible participants were randomly allocated to either Probio-Tec^®BG-VCap-6.5 [containing Lactobacillus rhamnosus (LGG^®) and Bifidobacterium animalis subsp. Lactis (BB-12^®)] + Magnesium chloride or placebo for 9 weeks. Sociodemographic data were collected in the beginning. Anthropometric, dietary and physical activity (PA) assessments were carried out. Beck Depression Inventory-II (BDI-II) and Montreal Cognitive Assessment (MoCA) scores were assessed through validated questionnaires. Fasting plasma zonulin, lipopolysaccharide (LPS) and (CRP) were measured by ELIZA kits.

Results

Of seventy-four participants (mean age 37.51 ± 8.10), 52 completed the study. Changes in serum LPS and zonulin were not different significantly between groups (−3.04 ± 44.75 ng/dl, 0.11 ± 5.13, ng/dl, p > 0.05 for LPS and 1.40 ± 48.78 ng/dl, −0.17 ± 6.60, p > 0.05 for zonulin, respectively). CRP levels reduced significantly in intervention group compared to placebo [−474.75 (−1,300.00, −125.00) mg/l vs. 175.20 (−957.75, 1,683.25) mg/l, p = 0.016]. Changes in BDI-II and MoCA scores were not significantly different between intervention (−7.13 ± 5.67, 1.20 ± 2.16, respectively) and placebo (−5.42 ± 6.71, 1.94 ± 1.86, respectively) groups (p > 0.05).

Conclusion

Nine weeks of probiotic and magnesium co-supplementation resulted in decreased CRP levels as an indicator of inflammatory state with no significant effects on mood, cognition and intestinal integrity in individuals with obesity and depressed mood.

Lactobacillus rhamnosus GG Promotes Intestinal Vitamin D Absorption by Upregulating Vitamin D Transporters in Senile Osteoporosis

Intestinal absorption of vitamin D is an important way to improve the vitamin D level in senile osteoporosis (SOP). There is a link between oral probiotics and vitamin D, but the mechanism is still unclear. We aimed to evaluate whether Lactobacillus rhamnosus GG culture supernatant (LCS) can affect cholecalciferol absorption, transport, and hydroxylation in SOP, and explore underlying mechanisms. In the study, specific-pathogen-free SAMP6 mice were randomly divided into an experimental group administered undiluted LCS and a control group administered normal drinking water. Furthermore, levels of cholecalciferol absorption were compared between Caco-2 cells cultured with varying concentrations of cholecalciferol and stimulated with LCS or de Man, Rogosa, and Sharpe (MRS) broth (control). Similarly, LCS-stimulated HepG2 cells were compared with MRS-stimulated HepG2 cells. Finally, protein levels of VD transporters in small intestine tissues and Caco-2 cells, as well as vitamin D-binding protein and 25-hydroxylase in liver tissues and HepG2 cells, were detected by western blot. The results showed that plasma concentrations of cholecalciferol and 25OHD₃ were higher in mice of the LCS group compared with the control group, and these values were positively correlated. With the addition of LCS, cholecalciferol uptake was increased with 0.5 μM or 10 μM cholecalciferol in the medium. Protein levels of CD36 and NPC1L1 were higher in the LCS group compared with the control group, while SR-BI protein was decreased, both in vitro and in vivo. In conclusion, LCS can promotes intestinal absorption cholecalciferol by affecting protein levels of VD transporters and improves 25OHD₃ levels in SOP.

The Effect of Vitamin D Supplementation on Serum 25-Hydroxy Vitamin D in the Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-Analysis of Randomized Clinical Trials

Currently, there is no consensus on the optimal vitamin D administration in bariatric patients. The present systematic review and meta-analysis were conducted to examine the effect of vitamin D supplements on serum level of 25(OH) vitamin D in the patients undergoing bariatric surgery (BS).Random model effects were used to estimate standardized mean difference (SMD) with a 95% confidence interval (CI). Nine clinical trials were included in the meta-analysis. Vitamin D supplementation in patients undergoing BS modestly improves vitamin D status (SMD, 0.53; 95% CI, 0.28, 0.77) particularly, in the dosages above 2850 IU/day and in the patients with BMI greater than 50 kg/m². Vitamin D supplementation was associated with prevention of raising of the PTH serum concentration and without impact on serum calcium levels.

Effect of time restricted feeding on anthropometric measures, eating behavior, stress, and brain-derived neurotrophic factor (BDNF) and lipopolysaccharide-binding protein (LBP) levels in women with overweight/obesity and food addiction: a study protocol for a randomized clinical trial

Background

Food addiction is one of the behavioral factors that play an important role in the pathogenesis of obesity. Much evidence is available suggesting intestinal microbiomes can play a role in eating behavior, body composition, and BDNF levels, and they can be modified by time-restricted feeding (TRF). So, this study will aim to evaluate the effect of TRF on anthropometric measures, eating behavior, stress, and serum BDNF and LBP levels in women with overweight/obesity and food addiction.

Methods

We will carry out a randomized clinical trial for 8 weeks to evaluate the effect of a TRF on anthropometric measures, eating behavior, stress level, serum BDNF and LBP levels in women with overweight/obesity and food addiction.

Discussion

Given the effect of BDNF on regulating eating behavior and body weight and the effect of dietary restrictions on BDNF and the gut microbiome, the TRF diet could possibly be a new way to successfully manage weight through modifying BDNF in people with eating disorders, including food addiction.

Trial registration

Iranian Registry of Clinical Trials IRCT20131228015968N7. Registered on 25 October 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06439-x.

Gut microbiota in bariatric surgery

Gut microbes share a symbiotic relationship with humans and perform several metabolic and physiological functions essential for human survival. It has been established in several scientific studies that obesity and other metabolic complications are always associated with disturbed gut microbiota profile, also called gut dysbiosis. In recent years, bariatric surgery has become a treatment of choice for weight loss, and it forms an important part of obesity management strategies across the globe. Interestingly, bariatric surgery has been shown to alter gut microbiota profile and synthesize short-chain fatty acids by gut microbes. In other words, gut microbes play a crucial role in better clinical outcomes associated with bariatric surgery. In addition, gut microbes are important in reducing weight and lowering the adverse events post-bariatric surgery. Therefore, several prebiotics, probiotics and postbiotics are recommended for patients who underwent bariatric surgery procedures for better clinical outcomes. The present review aims to understand the possible association between gut microbes and bariatric surgery and present scientific evidence showing the beneficial role of gut microbes in improving therapeutic outcomes of bariatric surgery.

Alterations in the composition of the gut microbiota affect absorption of cholecalciferol in severe osteoporosis

INTRODUCTION

To evaluate the relationship between the gut microbial composition and intestinal cholecalciferol absorption in patients with severe osteoporosis (SOP).

MATERIALS AND METHODS

Eighteen patients with primary osteoporosis (OP) and 18 with SOP were included. Their clinical data were collected and their circulating concentrations of cholecalciferol and 25(OH)D₃ were measured. Fecal samples were collected and their microbial contents were analyzed using 16S rDNA sequencing.

RESULTS

The age, sex, body mass index, and body mass of the participants did not differ between the groups. The prevalence of gastrointestinal symptoms in the participants with SOP was significantly higher than that in the participants with OP. There were significant differences in the 25(OH)D₃ and cholecalciferol concentrations between participants with SOP or OP and there was a significant positive correlation between the concentrations of these substance. The diversity of the gut microbiota in participants with SOP was significantly higher than that in participants with OP. Firmicutes was more abundant in the SOP group and the ratio of Firmicutes/Bacteroidetes in participants with SOP was higher. Conversely, Bifidobacterium was significantly less abundant, as were the order and family it belongs to. At the species level, Bifidobacterium was the most significant difference between the two groups.

CONCLUSION

Differences in the intestinal microecology, especially Bifidobacterium, are associated with differences in the absorption of cholecalciferol and in the circulating 25(OH)D₃ concentration, which may influence the progression of OP to SOP.

Intestinal barrier disorders and metabolic endotoxemia in obesity: Current knowledge

The World Health Organization reports that the prevalent problem of excessive weight and obesity currently affects about 1.9 billion people worldwide and is the fifth most common death factor among patients. In view of the growing number of patients with obesity, attention is drawn to the insufficient effectiveness of behavioral treatment methods. In addition to genetic and environmental factors leading to the consumption of excess energy in the diet and the accumulation of adipose tissue, attention is paid to the role of intestinal microbiota in maintaining a normal body weight. Dysbiosis – a disorder in the composition of the gut microbiota – is mentioned as one of the contributing factors to the development of metabolic diseases, including obesity, type 2 diabetes, and cardiovascular disorders. The human gastrointestinal tract is colonized largely by a group of Gram-negative bacteria that are indicated to be a source of lipopolysaccharide (LPS), associated with inducing systemic inflammation and endotoxemia. Research suggests that disturbances in the gut microbiota, leading to damage to the intestinal barrier and an increase in circulating LPS, are implicated in obesity and other metabolic disorders. Plasma LPS and lipopolysaccharide-binding protein (LBP) levels have been shown to be elevated in individuals with excess body weight. Bariatric surgery has become a popular treatment option, leading to stable weight loss and an improvement in obesity-related conditions. The aim of this study was to characterize the factors that promote the induction of metabolic endotoxemia and its associated health consequences, along with the presentation of their changes after bariatric surgery.

The association of weight loss with changes in the gut microbiota diversity, composition, and intestinal permeability: a systematic review and meta-analysis

The gut microbiome may be a mediator between obesity and health outcomes. However, it is unclear how intentional weight loss changes the gut microbiota and intestinal permeability. We aimed to systematically review and quantify this association. We searched Medline, Embase, CINAHL, Cochrane databases, and trial registries until June 2020 (PROSPERO: CRD42020205292). We included trials of weight loss interventions (energy-restricted diets, pharmacotherapy, bariatric surgery) reporting on the microbiome. Two reviewers independently completed screening, extraction, and risk assessment with the ROBINS-I tool. Pooled standardized mean differences (SMDs) were obtained from random-effects meta-analyses. Forty-seven trials with 1,916 participants (81% female) and a median follow-up of 6 months (range: 2-24) were included. Based on imprecise evidence but with fairly consistent direction of effect, weight loss was associated with a statistically significant increase in α-diversity [SMD: 0.4 (95% CI: 0.2, 0.6], p < .0001, I² = 70%, n = 30 studies) and a statistically significant reduction in intestinal permeability [SMD: -0.7 (95% CI: -0.9, -0.4), p < .0001, I² = 83%, n = 17 studies]. Each kg of weight loss was associated with a 0.012 (95% CI: 0.0003, 0.024, p = .045) increase in α-diversity and a -0.017 (95% CI: -0.034, -0.001, p = .038) reduction in intestinal permeability. There was clear evidence of increases in the relative abundance of Akkermansia, but no clear evidence of changes in individual phyla, species, or fecal short-chain fatty acids. Restricting the analyses to the studies with lower risk of bias did not materially alter the estimates. Increasing weight loss is positively associated with increases in gut microbiota α-diversity and reductions in intestinal permeability.

A Specifically Tailored Multistrain Probiotic and Micronutrient Mixture Affects Nonalcoholic Fatty Liver Disease-Related Markers in Patients with Obesity after Mini Gastric Bypass Surgery

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is frequent among patients undergoing bariatric surgery. Beyond weight reduction, dietary supplements like micronutrients or probiotics that modify insulin resistance and lipotoxicity can be used to prevent or delay the progression of liver disease.

OBJECTIVES

We evaluated the effect of a dietary approach with a specifically tailored multistrain probiotic and micronutrient mixture compared with a basic care micronutrient supplement on serum alanine aminotransferase (ALAT) in obese patients after mini gastric bypass (MGB) surgery.

METHODS

This randomized, double-blind, controlled trial included 60 obese patients (age: 40 ± 10 y; BMI: 44 ± 3 kg/m²). Patients received a combination of specifically tailored multistrain probiotic powder and a specific micronutrient mixture (Pro+SM) or a control treatment consisting of a placebo and a basic care micronutrient mixture (Con+BM), with some micronutrients in lower doses than SM, for 12 wk after hospital discharge. Primary (serum ALAT) and secondary outcomes [serum aspartate aminotransferase (ASAT), fatty liver index, NAFLD fibrosis score, glucose metabolism, blood pressure (BP), heart rate] were assessed at week 0 and week 12. Data were analyzed using unpaired Student's t-tests or Mann-Whitney U tests to compare the changes due to each treatment to one another.

RESULTS

A total of 48 patients were included in the analyses. Changes in serum ALAT concentrations did not differ between groups. Compared with Con+BM, Pro+SM improved serum ASAT (difference: -8.0 U/L, 95% CI: -17.0, -4.0; P = 0.043), NAFLD fibrosis score (difference: -0.39; 95% CI: -0.78, 0; P = 0.048), serum triglycerides (difference: -22.8 mg/dL; 95% CI: -45.6, -0.1; P = 0.049) and the visceral adiposity index (difference: -0.70; 95% CI: -1.31, -0.08; P = 0.027).

CONCLUSION

Supplementation with a specifically tailored probiotic and micronutrient mixture improved NAFLD-related markers more than a basic micronutrient mixture in obese patients following MGB surgery. The trial was registered under clinicaltrials.gov as NCT03585413.

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.

Shifts in gut microbiota and their metabolites induced by bariatric surgery. Impact of factors shaping gut microbiota on bariatric surgery outcomes

Evidence suggests that bariatric surgery alters gut microbiota, although its impact at compositional and functional level is not well described. In this review, the most relevant findings, mainly described in Roux-en-Y gastric bypass and sleeve gastrectomy, are outlined. Although the number of studies has increased in the last years, conclusive assertions cannot be elaborated. An issue to address is to know the influence of these alterations on host metabolism and the contribution of gut microbiota derived metabolites. New lines of research have been focusing on analysing gut microbiota functionality rather than evaluating changes at compositional level, and the functions of gut microbiota metabolites in host metabolism, what will bring more relevant information about the influence of gut microbiota in bariatric surgery outcomes. Personalized medicine, because of the predictive value of gut microbiota, is another promising field. The possibility of a specific gut microbiota pattern that could predict type 2 diabetes remission or weight loss failure after bariatric surgery is a matter of great interest. However, little is known about how gut microbiota manipulation could contribute to the beneficial effects of bariatric surgery. Peri-operative antibiotics prophylaxis or probiotic supplementation early after surgery, are strategies barely studied so far, and could constitute a novel tool in the management of weight loss and metabolic profile improvement after surgery.

Probiotic Supplementation and Micronutrient Status in Healthy Subjects: A Systematic Review of Clinical Trials

Micronutrient deficiencies are a worldwide public health concern. Emerging evidence supports the ability of probiotics to enhance micronutrient status, which could aid in the prevention of non-communicable disease-associated malnutrition. This systematic review evaluated evidence of the efficacy of probiotic supplementation to improve micronutrient status in healthy subjects. The authors searched for published English language peer-reviewed journal articles in PubMed, Scopus, Embase, and Google Scholar databases from inception to July 2020 using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of eligible studies was assessed using the Revised Cochrane Risk-of-Bias tool (RoB)2 and Risk of Bias in Non-Randomized Studies of Interventions tool (ROBINS-I tool). Fourteen original studies out of 2790 met the inclusion criteria. The results indicated that, despite varying degrees of efficacy, the intake of certain probiotics in healthy subjects was associated with a positive impact on the status of certain micronutrients (vitamin B12, calcium, folate, iron and zinc). A limitation was that studies were widely heterogeneous in terms of participant age, probiotic strain, species, dosage, intervention duration, and form of administration. Additional clinical trials are warranted to determine the most effective strains of probiotics, doses and durations of interventions.

Probiotics Can Further Reduce Waist Circumference in Adults with Morbid Obesity after Bariatric Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Whether probiotics could be used as an adjunct to bariatric surgery is controversial. This meta-analysis aimed to evaluate the effects of probiotics on body weight, body mass index (BMI), percentage of the excess weight loss (%EWL), waist circumference (WC), and C-reactive protein (CRP) in adults with obesity after bariatric surgery (BS). PUBMED, EMBASE, and the Cochrane Central Registry of Controlled Trials were searched from the earliest record to March 2020. All randomized controlled trials (RCTs) on the effects of probiotics in adults with obesity after bariatric surgery were analyzed according to the eligibility criteria. Four RCTs, including 172 participants, were analyzed. There was a statistically significant difference in probiotics in the reduction of waist circumference at 12 months after bariatric surgery. However, probiotics were not effective in weight, BMI, %EWL, WC, and CRP both within 3 months and at 12 months postoperation. Probiotics aid adults with morbid obesity in achieving further waist circumference improvement after BS, with no significant effect on weight, BMI, %EWL, and CRP. More quality clinical studies are needed to confirm the efficacy and safety of probiotics, and address a number of practical issues before the routine clinical use of probiotics in adults with obesity undergoing BS.

Multidisciplinary Approach for Weight Regain-how to Manage this Challenging Condition: an Expert Review

Weight regain is a multifactorial condition that affects many patients following bariatric surgery. The purpose of the paper is to review the multidisciplinary approach for the management of weight regain. We performed a search in current clinical evidence regarding the causes, consequences, and treatments of weight regain. The multidisciplinary approach with periodic monitoring is of fundamental importance to prevent or treat weight regain. Several therapeutic options are ranging from nutritional to surgical options, which should be tailored according to patients' anatomy, lifestyle behavior, and compliance. Specialized multidisciplinary care is the key to achieve optimal long-term weight loss and maintenance goals following bariatric surgery.

Comparison of probiotic yogurt and ordinary yogurt consumption on serum Pentraxin3, NT-proBNP, oxLDL, and ApoB100 in patients with chronic heart failure: a randomized, triple-blind, controlled trial

BACKGROUND AND AIMS

Nowadays, the potential beneficial effects of probiotic yogurt as a functional food has raised much interest. Thus, the aim of this study was to compare the probiotic yogurt and ordinary yogurt consumption on some indices in patients with chronic heart failure (CHF).

METHODS AND RESULTS

In this randomized, triple-blind clinical trial, 90 patients with CHF were randomly allocated into two groups to take either probiotic yogurt or ordinary yogurt for 10 weeks. The serum levels of pentraxin3 (PTX3), N-terminal pro-brain natriuretic peptide (NT-proBNP), oxidized low density lipoprotein (oxLDL), and apolipoprotein B100 (ApoB100) were measured at the baseline and at the end of week 10. P-Value <0.05 was defined as statistically significant. Final analyses were performed on 78 patients. The levels of PTX3 and oxLDL in both the groups decreased significantly after 10 weeks, and these reductions were greater in the probiotic group, where the difference between the groups was statistically significant for oxLDL (P-value: 0.051, adjusted P-value: 0.010) but not significant for PTX3 (P-value: 0.956, adjusted P-value: 0.236). The changes in the serum NT-proBNP levels were not statistically significant between the groups (P-value: 0.948, adjusted P-value: 0.306). ApoB100 significantly decreased in the control group compared to the probiotic group and the difference between the groups was significant at first but was not significant after adjusting for the confounders (P-value: 0.004, adjusted P-value: 0.280).

CONCLUSION

The serum oxLDL significantly reduced due to probiotic yogurt consumption after 10 weeks compared to ordinary yogurt; thus, it may be useful for improving the oxidative status of CHF patients. The clinical trial registry number is IRCT20091114002709N48 (https://www.irct.ir/IRCT20091114002709N48, registered 12 March 2018).

Fermented milk containing Lactobacillus casei Zhang and Bifidobacterium animalis ssp. lactis V9 alleviated constipation symptoms through regulation of intestinal microbiota, inflammation, and metabolic pathways

Studies suggest that probiotics and fermented milk can improve defecation in constipated patients. However, the mechanism of fermented milk containing probiotics on constipation remains poorly understood. Volunteers with chronic constipation symptoms were recruited and given 200 g/d of fermented milk containing Lactobacillus casei Zhang and Bifidobacterium animalis ssp. lactis V9 (PFM) for 4 wk. Clinical symptoms, cytokines, metagenomics, and metabolomics were evaluated in constipated participants before and after PFM intervention. After PFM intervention, we observed significant improvement of constipation symptoms. In the serum samples, the anti-inflammatory cytokine IL-10 increased and the proinflammatory cytokine C-reactive protein and lipopolysaccharides decreased. Metagenomics results showed that the increase of B. animalis was correlated with an increase in defecation frequency. Fatty acid biosynthesis and bile acid biosynthesis in stool samples as well as carnitine shuttle, vitamin E metabolism, and ascorbate and aldarate metabolism were identified as significantly altered metabolic pathways. Acylcarnitine, located on the carnitine shuttle pathway, had a significantly positive correlation with defecation frequency. It was speculated that PFM may contribute to alleviating constipation symptoms through 3 potential mechanisms: fine-tuning gastrointestinal microbiota, fighting inflammation, and regulating metabolic pathways.

The effects of probiotic/synbiotic supplementation compared to placebo on biomarkers of oxidative stress in adults: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

During the last decades, there has been a burst of scientific literature hypothesizing the antioxidant effect of probiotics. However, the results of these studies are inconsistent and a final conclusion has yet to be reached. Thus, the aim of this study was to assess the effects of probiotic/synbiotic supplementation on serum total antioxidant capacity (TAC), glutathione (GSH), malondialdehyde (MDA) and nitric oxide (NO) levels in adults.

METHODS AND RESULTS

The following online databases were searched until August 26th 2020: PubMed/Medline, Scopus, Clarivate Analytics Web of Science, Cochrane Central Register of Controlled Trials, Science Direct, Google Scholar and Igaku Chuo Zasshi. The effect sizes were expressed as the weighted mean difference (WMD) with 95% confidence intervals (CI). A total of 31 eligible trials with 1681 participants (839 cases and 842 controls) were included in this meta-analysis. The results revealed that the supplementation with probiotics/synbiotics, significantly increased serum TAC (WMD: 54.14 mmol/L, 95% CI: 27.87, 80.40, P < 0.001), GSH (WMD: 40.38 μmol/L, 95% CI: 20.72, 60.03, P < 0.001) and NO (WMD: 3.54 μmol/L, 95% CI: 1.73, 5.34, P < 0.001) levels. In addition, MDA levels were significantly reduced (WMD: -0.45 μmol/L, 95% CI: -0.58,-0.32, P < 0.001) following probiotic/synbiotic supplementation. None of the variables showed a significant change in the sensitivity analysis.

CONCLUSION

Available evidence suggests that probiotic/synbiotic supplementation can significantly increase serum TAC, GSH and NO, as well as reduce MDA levels in adults. Therefore, probiotic/synbiotic supplementation may play a role in improving antioxidant indices and reducing oxidative stress in the body.

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

Bariatric surgery is considered effective for morbid obesity, and probiotic supplementation might provide some benefits. We aimed to revise the evidence regarding probiotic supplementation in patients with morbid obesity undergoing bariatric surgery. MEDLINE, Embase, Web of Science, CENTRAL, and trial registers were searched up to April 1, 2020. We included randomized controlled trials and controlled clinical trials, and outcomes of interest were weight change, quality of life, gastrointestinal symptoms, and adverse events. All stages of the review were done by 2 authors independently and we followed Cochrane Handbook guidance. We screened 2541 references and included 5 studies. Probiotics may have minor to no effect regarding percentage excess weight loss (%EWL) at 6 weeks (mean difference [MD], .28; 95% CI, -9.53 to 10.09; 44 participants, 2 studies), 3 months (MD, 5.47; 95% CI, -3.22 to 14.17; 165 participants, 3 studies), 6 months (MD, .46; 95% CI, -8.14 to 9.07; 115 participants, 2 studies), and 12 months post surgery (MD, .35; 95% CI, -8.66 to 9.37; 123 participants, 2 studies). We observed short-term improvement in gastrointestinal symptoms. There was no important effect on quality of life and no meaningful adverse events. Because probiotic supplementation might provide some benefit with respect to weight loss, might alleviate some gastrointestinal symptoms, and is associated with minor or no adverse events, continuous supplementation might be worth considering in certain individuals. Our findings are based on the body of evidence of very low certainty, and further well-designed randomized controlled trials are required to elucidate the effect and strengthen the certainty in the estimates.

Comparison of methodological approaches to human gut microbiota changes in response to metabolic and bariatric surgery: A systematic review

Substantial differences in the response of gut microbial composition to metabolic and bariatric surgery have been reported. Therefore, the goal of the present review is to evaluate if methodological differences could be driving this lack of consistency. A search was conducted using PUBMED, Web of Science, Science Direct and COCHRANE using the following inclusion criteria: human studies written in English with a baseline sampling point, using gut microbiota as an outcome and either Roux-n-Y gastric bypass or sleeve gastrectomy. Sixteen articles were selected (total 221 participants). Roux-n-Y gastric bypass caused more alterations in gut microbial composition in comparison with sleeve gastrectomy. Substantial variability was found in study designs, data collection and analyses across studies. Increases in several families and genera from the phylum Proteobacteria and Bacteroidetes, the family Streptococcaceae, the species Akkermansia muciniphila and Streptococcus salivarius and a decrease in the phylum Firmicutes and the family Bifidobacteriaceae were reported. There is a need for standardization not only of microbial analysis but also of study designs when analysing the effect of bariatric surgery on the human gut microbiome. In addition, outcomes from different surgical procedures should not be combined as they produce distinctive effects on gut microbial composition.

Are Probiotics the New Calcium and Vitamin D for Bone Health?

PURPOSE OF REVIEW

Calcium and vitamin D supplementation is recommended for patients at high risk of fracture and/or for those receiving pharmacological osteoporosis treatments. Probiotics are micro-organisms conferring a health benefit on the host when administered in adequate amounts, likely by influencing gut microbiota (GM) composition and/or function. GM has been shown to influence various determinants of bone health.

RECENT FINDINGS

In animal models, probiotics prevent bone loss associated with estrogen deficiency, diabetes, or glucocorticoid treatments, by modulating both bone resorption by osteoclasts and bone formation by osteoblast. In humans, they interfere with 25-hydroxyvitamin D levels, and calcium intake and absorption, and slightly decrease bone loss in elderly postmenopausal women, in a quite similar magnitude as observed with calcium ± vitamin D supplements. A dietary source of probiotics is fermented dairy products which can improve calcium balance, prevent secondary hyperparathyroidism, and attenuate age-related increase of bone resorption and bone loss. Additional studies are required to determine whether probiotics or any other interventions targeting GM and its metabolites may be adjuvant treatment to calcium and vitamin D or anti-osteoporotic drugs in the general management of patients with bone fragility.

Short term effects of coffee components consumption on gut microbiota in patients with non-alcoholic fatty liver and diabetes: A pilot randomized placebo-controlled, clinical trial

The aim of this study was to determine the effects of caffeine and chlorogenic acid supplementation on gut microbiota, and metabolic disturbances in patients with NAFLD and diabetes. In this randomized, placebo-controlled, clinical trial, 26 patients with diabetes and NAFLD were randomly assigned to four groups to receive either 200 mg caffeine plus 200 mg chlorogenic acid (CFCA), or 200 mg caffeine plus 200 mg placebo (starch) (CFPL), or 200 mg chlorogenic acid plus 200 mg placebo (CAPL), or 200 mg placebo plus 200 mg placebo (PLPL) for 12 weeks. After 3 months of supplementation, patients in the intervention groups showed a significant decrease in body weight (CFCA group =-3.69 kg; CFPL group=-0.7kg; CAPL group=-0.43kg; PLPL group=0.26 kg) (p=0.004). Weight reduced significantly more in CFCA group compared to all other three groups (p=0.005 for PLPL; p=0.023 for CAPL; and p=0.031 for CFPL). Although the number of gut Bifidobacteria increased in CFCA group, there were no statistically significant differences within and between the groups in any of bacteria numbers. In conclusion, our study showed that 12 weeks consumption of 200 mg/day caffeine plus 200 mg/day chlorogenic acid is effective in reduction of weight in patients with NAFLD and diabetes which might be at least partially through the rise in gut Bifidobacteria. This pilot study shed a light on the pathway of future clinical trials assessing the effects of coffee consumption in these patients. This trial has been registered at clinicaltrial.gov with registration number of NCT02929901.