What’s the Latest in Prebiotic Research? – March 2023 Edition
The effect of synbiotic supplementation on hypothyroidism: A randomized double-blind placebo controlled clinical trial
Hypothyroidism is a common disease worldwide, affecting up to 5% of the general population. Hypothyroidism is a thyroid dysfunction that reduces thyroid hormone production, leading to high blood pressure, depression, mood disturbances, and poor health-related quality of life. The gut microbiota can manipulate micronutrient absorption, changing thyroid function. As such, microbiota-modulating synbiotics may indirectly influence the production of thyroid hormones and improve other complications of hypothyroidism by stimulating advantageous changes on the microbial species in the gut. This randomized, double-blind, placebo-controlled trial investigated the modulatory effects of a synbiotic supplement on the intestinal microbiota and subsequent improvements in the condition of hypothyroid patients. Fifty-six adult hypothyroid patients received 500 mg of 109 CFU/g probiotics plus fructooligosaccharide (FOS) or a placebo for ten weeks. The primary outcomes were serum thyroid stimulating hormone (TSH) and free thyroxine (FT4), and the secondary outcomes were depression, quality of life, and blood pressure (BP). While TSH and depression did not change significantly, both synbiotic and placebo groups showed a significant increase in serum FT4. There also was a significant decrease in systolic BP and an increase in different domains and areas of quality of life in the crude and adjusted analysis, including perceived mental health, bodily pain, general health perception, and well-being. More studies are needed to support the use of synbiotics in hypothyroid patients.
- Ten weeks of synbiotic supplementation with 500 mg of 109 CFU/g probiotics plus FOS might be effective in enhancing quality of life and blood pressure in hypothyroid patients.
- Synbiotic supplementation did not affect serum TSH level and depression.
- Further studies are needed to support synbiotic supplementation in hypothyroid patients.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36745650/
Reference: Ramezani, M., Reisian, M., & Sajadi Hezaveh, Z. (2023). The effect of synbiotic supplementation on hypothyroidism: A randomized double-blind placebo controlled clinical trial. PloS one, 18(2), e0277213. https://doi.org/10.1371/journal.pone.0277213
The Efficacy of Gum Arabic in Managing Diseases: A Systematic Review of Evidence-Based Clinical Trials
Gum Arabic (GA) or acacia gum is an exudate obtained from Acacia segal and Acacia senegal branches. GA is found in Sudan, Chad, and Nigeria where it is commonly used for treating various diseases. This systemic review aimed to assess available clinical trials that explore the use of GA in human subjects for medical disease management. Of the three databases searched, twenty-nine papers met the inclusion criteria. Of the selected studies, 31.0% were related to metabolic disorders (e.g., type 2 diabetes and hyperlipidemia), 17.2% related to gastrointestinal health, 17.2% related to oral health, 13.9% related to kidney disease, 10.3% related to sickle cell anemia, 6.9% related to rheumatoid arthritis, and 3.4% related to drug efficacy. It was reported that the ingestion of GA positively affects lipid profiles, renal profiles, plaque, gingival scores, biochemical parameters, blood pressure, inflammatory markers, and adiposity through exhibiting anti-inflammatory, antibacterial, and prebiotic properties. Additional research is warranted to investigate the exact mechanism of action of the active components of GA for each medical condition.
- GA is traditionally used in the Sub-Saharan African region as a remedy for various health conditions.
- Human clinical trials have explored GA’s use in sickle cell anemia, kidney disease, rheumatoid arthritis, metabolic disorders, and oral health management.
- More research exploring the exact mechanism of action of GA is needed.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36671523/
Reference: Al-Jubori, Y., Ahmed, N. T. B., Albusaidi, R., Madden, J., Das, S., & Sirasanagandla, S. R. (2023). The Efficacy of Gum Arabic in Managing Diseases: A Systematic Review of Evidence-Based Clinical Trials. Biomolecules, 13(1), 138. https://doi.org/10.3390/biom13010138
Intake of Pro- and/or Prebiotics as a Promising Approach for Prevention and Treatment of Colorectal Cancer
Colorectal cancer (CRC) is the third most common type of cancer and one of the most fatal worldwide. Although more than 90% of CRC cases are sporadic, lifestyle factors like smoking, ingestion of excess alcohol and processed meat, and frequent use of antibiotics may be responsible for CRC onset. Additional factors such as the diversity of an individual’s intestinal microflora, the integrity of the intestinal barrier, and the presence of mutagenic/carcinogenic/genotoxic and beneficial compounds are known to influence the development of CRC greatly. As such, there has been an interest in probiotics and prebiotics and their efficacy in CRC prevention and treatment as microbiome-modulating agents. This report summarized the benefits of prebiotic and probiotic supplementation for CRC prevention and treatment and reviewed the available mechanisms underlying their efficacy. Mechanisms such as balancing the gut microbiota composition, reducing intestinal inflammation, strengthening the intestinal barrier, and producing beneficial metabolites may inhibit the proliferation of cancer cells and induce apoptosis. More research, including longitudinal studies, that employs multi-omics may be beneficial for understanding the chronology of CRC through analyzing the microbiota, enzymatic, and metabolite changes at different stages of CRC.
- Factors such as microbiome diversity, intestinal barrier integrity, and the effect of toxic compounds may lead to CRC development.
- Both probiotics and prebiotics have been shown, through various mechanisms, to assist in preventing and treating CRC.
- CRC remains a complex disease and further understanding of its pathology is needed to decipher the use of probiotics and prebiotics in this patient population.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36349520/
Reference: Wang, H., Chen, K., Ning, M., Wang, X., Wang, Z., Yue, Y., Yuan, Y., & Yue, T. (2023). Intake of Pro- and/or Prebiotics as a Promising Approach for Prevention and Treatment of Colorectal Cancer. Molecular nutrition & food research, 67(3), e2200474. https://doi.org/10.1002/mnfr.202200474
Sex difference in prebiotics on gut and blood-brain barrier dysfunction underlying stress-induced anxiety and depression
Depression is one of the significant health-related causes of disability worldwide. Generally, females tend to show higher vulnerability to depression and anxiety across their lifespan than males. Recent studies have shown that the gut microbiota may play a vital role in depression. However, females have inadequately been represented when studying prebiotic supplements and their potential anti-depressive and anxiolytic roles. As such, this animal study assessed sex differences in prebiotics on stress-induced depression-like and anxiety-like behaviour, inflammation, and gut and blood-brain barrier (BBB) dysfunction. Female and male C57BL/J mice (aged 6-8 weeks) were randomly divided into three groups: chronic restraint stress (CRS), CRS+prebiotic (CP), and control (CON) group. Mice in the CRS group were fed water and restrained for 4 h every day for three consecutive weeks. Animals in the CP group received the prebiotic (0.3-0.4 g/mouse/day of a combination of FOS and galactooligosaccharides (GOS)) and were restrained for 4 h every day for three consecutive weeks. Mice in the CON group were fed water without stress. Three-week use of FOS+GOS attenuated stress-induced anxiety-like behaviour in females but not in male mice, with the anxiolytic effects in males observed until week 4. The protective effects of prebiotics on CRS-induced depression were not observed; however, prebiotics alleviated stress-induced BBB dysfunction and elevation in the pro-inflammatory cytokine levels and modulated the gut microbiota in both males and females. Gene expression changes and goblet cell levels were also restored with prebiotics, but only in females. Altogether, female mice showed more vulnerability to stress and responsiveness to prebiotics than males.
- Females show higher vulnerability to depression and anxiety than males over their lifespan.
- Most previous research has explored prebiotics’ anti-depressive and anxiolytic effects in males, with few female subjects included.
- The protective effects of prebiotics on anxiety-like behaviours in female mice may be mediated by the gut microbiota, gut and blood-brain barrier, and inflammatory responses.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36650644/
Reference: Jiang, J., Fu, Y., Tang, A., Gao, X., Zhang, D., Shen, Y., Mou, T., Hu, S., Gao, J., & Lai, J. (2023). Sex difference in prebiotics on gut and blood-brain barrier dysfunction underlying stress-induced anxiety and depression. CNS neuroscience & therapeutics, 10.1111/cns.14091. Advance online publication. https://doi.org/10.1111/cns.14091