Key points
- The gut microbiome is likely to play an important role in metabolic syndrome and obesity
- The gut and microbiome have a bidirectional relationship with causative factors of diabesity; hunger, satiety, inflammation and immunity
- Probiotics including Lactobacillus and Bifodobacteria species might be of benefit to the treatment of metabolic disorders
The gut microbiota has been implicated in many disorders and an appropriate diversity and balance of bacteria and other microbes in the gut is considered to be a crucial aspect of our foundations of health.1
The gut microbiome has a specific, bidirectional relationship with hunger, satiety, inflammation and immunity, all of which interplay with the spectrum of metabolic disorder including obesity, metabolic syndrome, and diabetes.2-5 As covered in a previous article, the gut microbiome also has an interplay with sleep and stress, also cofactors for the development of diabetes and obesity.
Metabolites produced by the gut and microbiota (related to dysbiosis) may also be important for the gut-diabetes interaction. A dose‐response meta‐analysis was used to investigate the relationship between diabetes and TMAO, a damaging chemical produced in greater concentrations with higher relative Clostridiales,Ruminococcus, and Lachnospiraceae and reduced Bacteroidetes. Higher levels of circulating TMAO were found in the diabetic participants, and high levels of TMAO were associated with an increased risk of diabetes[i].6
The gut microbiome and type 1 diabetes
A systematic review of 568 papers (resulting in analysis of 26 studies with 2600 children and 189 adults), identified overwhelmingly that there are differences in the gut microbiota of people with and without type 1 diabetes with the most common bacterial alterations including, Bacteroides spp., Streptococcus spp., Clostridium spp., Bifidobacterium spp., Prevotella spp., Staphylococcus spp., Blautia spp., Faecalibacterium spp., Roseburia spp., and Lactobacillus spp. However, the authors noted that it is difficult to identify causation and bacterial alterations may result from metabolic disorder.7
Probiotics for weight management and metabolic syndrome
In a systematic review of over 100 articles (n = 6826), probiotics improved many aspects of health for people with overweight (but not obesity).
In type 2 diabetics, probiotics improved fasting blood glucose, HbA1c, insulin, and insulin homeostasis, while in patients with fatty liver disease, probiotics improved liver enzyme profiles.
Improvements for these outcomes were mostly seen with supplementation of bifidobacteria (Bifidobacterium breve, B. longum), Streptococcus salivarius subsp. Thermophilus and lactobacilli (Lactobacillus acidophilus, L. casei, L. delbrueckii).8
Probiotic use for metabolic disorders
Probiotic supplementation overall shows benefits to fasting glucose levels, lipids, insulin and sensitivity, and systemic inflammation (especially by reducing Il-6 and CRP) in people with type 2 and gestational diabetes.9-14 A recent (2019) systematic review of trials concluded that “multistrain probiotics that contain seven million to 100 billion colony forming units of Lactobacillus acidophilus, Streptococcus thermophilus, Lactobacillus bulgaricus, and/or Bifidobacterium lactis administered for 6 to 12 weeks may be efficacious for improving glycaemic control in adults with type 2 diabetes.”15 Additionally, probiotic, prebiotic (starch and fibre) and synbiotic supplements are likely to improve other aspects of metabolic disease, including non-alcoholic fatty liver disease.16
While some reviews show inconsistent effects of probiotics on HbA1c, inflammation and oxidative stress, it is also noted that attention needs to be paid to the probiotic strains used and the target population.17
References
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2. Singer-Englar T, Barlow G, Mathur R. Obesity, diabetes, and the gut microbiome: an updated review. Expert review of gastroenterology & hepatology. 2019;13(1):3-15.
3. Zheng P, Li Z, Zhou Z. Gut microbiome in type 1 diabetes: A comprehensive review. Diabetes/metabolism research and reviews. 2018;34(7):e3043.
4. Wilson AS, Koller KR, Ramaboli MC, Nesengani LT, Ocvirk S, Chen C, et al. Diet and the Human Gut Microbiome: An International Review. Digest Dis Sci. 2020;65(3):723-40.
5. van den Munckhof ICL, Kurilshikov A, ter Horst R, Riksen NP, Joosten LAB, Zhernakova A, et al. Role of gut microbiota in chronic low-grade inflammation as potential driver for atherosclerotic cardiovascular disease: a systematic review of human studies. Obesity Reviews. 2018;19(12):1719-34.
6. Zhuang R, Ge X, Han L, Yu P, Gong X, Meng Q, et al. Gut microbe–generated metabolite trimethylamine N-oxide and the risk of diabetes: A systematic review and dose-response meta-analysis. Obesity Reviews. 2019;20(6):883-94.
7. Jamshidi P, Hasanzadeh S, Tahvildari A, Farsi Y, Arbabi M, Mota JF, et al. Is there any association between gut microbiota and type 1 diabetes? A systematic review. Gut pathogens. 2019;11(1):49.
8. Koutnikova H, Genser B, Monteiro-Sepulveda M, Faurie J-M, Rizkalla S, Schrezenmeir J, et al. Impact of bacterial probiotics on obesity, diabetes and non-alcoholic fatty liver disease related variables: a systematic review and meta-analysis of randomised controlled trials. BMJ open. 2019;9(3):e017995.
9. Tabrizi R, Ostadmohammadi V, Lankarani KB, Akbari M, Akbari H, Vakili S, et al. The effects of probiotic and synbiotic supplementation on inflammatory markers among patients with diabetes: A systematic review and meta-analysis of randomized controlled trials. European journal of pharmacology. 2019.
10. Kesika P, Sivamaruthi BS, Chaiyasut C. Do Probiotics Improve the Health Status of Individuals with Diabetes Mellitus? A Review on Outcomes of Clinical Trials. BioMed Research International. 2019;2019:1531567.
11. Hajifaraji M, Dolatkhah N. Probiotics and Metabolic Outcomes of Gestational Diabetes: A Review Article. Journal of Mazandaran University of Medical Sciences. 2018;28(162):155-74.
12. Homayouni A, Bagheri N, Mohammad-Alizadeh-Charandabi S, Kashani N, Mobaraki-Asl N, Mirghafurvand M, et al. Prevention of Gestational Diabetes Mellitus (GDM) and Probiotics: Mechanism of action: A Review. Curr Diabetes Rev. 2019.
13. Pan J, Pan Q, Chen Y, Zhang H, Zheng X. Efficacy of probiotic supplement for gestational diabetes mellitus: a systematic review and meta-analysis. The Journal of Maternal-Fetal & Neonatal Medicine. 2019;32(2):317-23.
14. Dallanora S, de Souza YM, Deon RG, Tracey CA, Freitas-Vilela AA, Roesch LFW, et al. Do probiotics effectively ameliorate glycemic control during gestational diabetes? A systematic review. Archives of gynecology and obstetrics. 2018;298(3):477-85.
15. Tiderencel KA, Hutcheon DA, Ziegler J. Probiotics for the treatment of type 2 diabetes: A review of randomized controlled trials. Diabetes/Metabolism Research and Reviews. 2020;36(1):e3213.
16. Sáez-Lara MJ, Robles-Sanchez C, Ruiz-Ojeda FJ, Plaza-Diaz J, Gil A. Effects of Probiotics and Synbiotics on Obesity, Insulin Resistance Syndrome, Type 2 Diabetes and Non-Alcoholic Fatty Liver Disease: A Review of Human Clinical Trials. International Journal of Molecular Sciences. 2016;17(6):928.
17. Samah S, Ramasamy K, Lim SM, Neoh CF. Probiotics for the
management of type 2 diabetes mellitus: A systematic review and meta-analysis.
Diabetes Research and Clinical Practice. 2016;118:172-82.
[i] OR = 1.89