Double-blinded, randomized clinical trial of Gegen Qinlian decoction pinpoints Faecalibacterium as key gut bacteria in alleviating hyperglycemia

Abstract

Background: Accumulating evidence suggests that metabolic disorders, including type 2 diabetes mellitus (T2DM), can be treated with traditional Chinese medicine formulas, such as the Gegen Qinlian decoction (GQD). This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.

Methods: We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM. During the 12-week intervention, anthropometric measurements and diabetic traits were recorded every 4 weeks. Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing, liquid chromatography-mass spectrometry, and Bio-Plex panels.

Results: Anti-diabetic effects were observed in the GQD group in the human trial. Specifically, glycated hemoglobin, fasting plasma glucose, and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group. Additionally, Faecalibacterium was significantly enriched in the GQD group, and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group. Moreover, Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin, fasting plasma glucose, and pro-inflammatory cytokines. Finally, the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzii (DSMZ 17677) in T2DM mouse model.

Conclusions: GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota, alleviating metabolic disorders and the inflammatory state.

Keywords

double-blinded randomized controlled trial / type 2 dia betes mellitus / Gegen Qinlian decoction / Faecalibacterium / metabolic disorders / inflammation

References

[1] Petersen MC, Shulman GI Mechanisms of insulin action and insulin resistance. Physiol Rev. 2018; 98:2133-223. https://doi.org/10.1152/physrev.00063.2017.

[2] International Diabetes Federation. IDF Diabetes Atlas, 10th Edition. Brussels, Belgium: 2021. Available at: https://diabetesatlas.org/atlas/tenth-edition/

[3] Zmora N, Bashiardes S, Levy M et al. The role of the immune system in metabolic health and disease. Cell Metab. 2017; 25:506-21. https://doi.org/10.1016/j.cmet.2017.02.006.

[4] Gao Z, Li Q, Wu X et al. New insights into the mechanisms of Chinese herbal products on diabetes: A focus on the "bacteria-mucosal immunity-inflammation-diabetes" axis. J Immunol Res. 2017;2017:1. https://doi.org/10.1155/2017/1813086.

[5] Krautkramer KA, Fan J, Backhed F Gut microbial metabolites as multi-kingdom intermediates. Nat Rev Microbiol. 2021; 19:77-94. https://doi.org/10.1038/s41579-020-0438-4.

[6] Fan Y, Pedersen O Gut microbiota in human metabolic health and disease. Nat Rev Microbiol. 2021; 19:55-71. https://doi.org/10.1038/s41579-020-0433-9.

[7] Shin NR, Lee JC, Lee HY et al. An increase in the Akkermansia spp. population induced by metformin treatment improves glucose homeostasis in diet-induced obese mice. Gut. 2014; 63:727-35. https://doi.org/10.1136/gutjnl-2012-303839.

[8] Wu H, Esteve E, Tremaroli V et al. Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug. Nat Med. 2017; 23:850-8. https://doi.org/10.1038/nm.4345.

[9] Xu J, Lian F, Zhao L et al. Structural modulation of gut microbiota during alleviation of type 2 diabetes with a Chinese herbal formula. ISME J. 2015; 9:552-62. https://doi.org/10.1038/ismej.2014.177.

[10] Xu X, Gao Z, Yang F et al. Antidiabetic effects of Gegen Qinlian decoction via the gut microbiota are attributable to its key ingredient berberine. Genom Proteom Bioinform. 2020; 18:721-36. https://doi.org/10.1016/j.gpb.2019.09.007.

[11] Nöst X, Pferschy-Wenzig EM, Yu XT et al. Comprehensive metabolic profiling of modified gegen qinlian decoction by ultra-high-performance liquid chromatography-diode array detection-Q-exactive-orbitrap-electrospray ionization-mass spectrometry/mass spectrometry and application of high-performance thin-layer chromatography for its fingerprint analysis. World J Tradit Chin Med. 2021;7:11‑32. https://doi.org/10.4103/wjtcm.wjtcm_63_20.

[12] Magoc T, Salzberg SL FLASH: fast length adjustment of short reads to improve genome assemblies. Bioinformatics. 2011; 27:2957-63. https://doi.org/10.1093/bioinformatics/btr507.

[13] Wang Q, Garrity GM, Tiedje JM et al. Naive Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy. Appl Environ Microbiol. 2007; 73:5261-7. https://doi.org/10.1128/AEM.00062-07.

[14] Irwin N, Flatt PR Therapeutic potential for GIP receptor agonists and antagonists. Best Pract Res Clin Endocrinol Metab. 2009; 23:499-512. https://doi.org/10.1016/j.beem.2009.03.001.

[15] Li Q, Cui Y, Xu B et al. Main active components of Jiawei Gegen Qinlian decoction protects against ulcerative colitis under different dietary environments in a gut microbiota-dependent manner. Pharmacol Res. 2021; 170(105694. https://doi.org/10.1016/j.phrs.2021.105694.

[16] Ling Z, Zhu M, Yan X et al. Structural and functional dysbiosis of fecal microbiota in Chinese patients with Alzheimer's disease. Front Cell Dev Biol. 2020;8:634069. https://doi.org/10.3389/fcell.2020.634069.

[17] Breuninger TA, Wawro N, Breuninger J et al. Associations between habitual diet, metabolic disease, and the gut microbiota using latent Dirichlet allocation. Microbiome. 2021;9:61. https://doi.org/10.1186/s40168-020-00969-9.

[18] Tilg H, Moschen AR Microbiota and diabetes: an evolving relationship. Gut. 2014; 63:1513-21. https://doi.org/10.1136/gutjnl-2014-306928.

[19] Munukka E, Pekkala S, Wiklund P et al. Gut-adipose tissue axis in hepatic fat accumulation in humans. J Hepatol. 2014; 61:132-8. https://doi.org/10.1016/j.jhep.2014.02.020.

[20] Pittayanon R, Lau JT, Leontiadis GI et al. Differences in gut microbiota in patients with vs without inflammatory bowel diseases: A systematic review. Gastroenterology. 2020; 158:930-46. https://doi.org/10.1053/j.gastro.2019.11.294.

[21] Coppola S, Avagliano C, Calignano A et al. The protective role of butyrate against obesity and obesity-related diseases. Molecules. 2021 Jan 28;26:682. https://doi.org/10.3390/molecules26030682.

[22] Sivaprakasam S, Prasad PD, Singh N Benefits of short-chain fatty acids and their receptors in inflammation and carcinogenesis. Pharmacol Ther. 2016; 164:144-51. https://doi.org/10.1016/j.pharmthera.2016.04.007.

[23] Riddy DM, Delerive P, Summers RJ et al. G protein-coupled receptors targeting insulin resistance, obesity, and type 2 diabetes mellitus. Pharmacol Rev. 2018; 70:39-67. https://doi.org/10.1124/pr.117.014373.

[24] Gross B, Pawlak M, Lefebvre P et al. PPARs in obesity-induced type 2 diabetes, dyslipidaemia and NAFLD. Nat Rev Endocrinol. 2017; 13:36-49. https://doi.org/10.1038/nrendo.2016.135.

[25] Huang L, Gao L, Chen C Role of medium-chain fatty acids in healthy metabolism: A clinical perspective. Trends Endocrinol Metab. 2021; 32:351-66. https://doi.org/10.1016/j.tem.2021.03.002.

[26] Arango Duque G, Descoteaux A Macrophage cytokines: involvement in immunity and infectious diseases. Front Immunol. 2014;5:491. https://doi.org/10.3389/fimmu.2014.00491.

[27] D'Esposito V, Ambrosio MR, Liguoro D et al. In severe obesity, subcutaneous adipose tissue cell-derived cytokines are early markers of impaired glucose tolerance and are modulated by quercetin. Int J Obes. 2021; 45:1811-20. https://doi.org/10.1038/s41366-021-00850-1.

[28] Mouquet F, Cuilleret F, Susen S et al. Metabolic syndrome and collateral vessel formation in patients with documented occluded coronary arteries: association with hyperglycaemia, insulin-resistance, adiponectin and plasminogen activator inhibitor-1. Eur Heart J. 2009; 30:840-9. https://doi.org/10.1093/eurheartj/ehn569.

[29] Scarale MG, Antonucci A, Cardellini M et al. A serum resistin and multicytokine inflammatory pathway is linked with and helps predict all-cause death in diabetes. Eur Heart J. 2009; 30:840-9. https://doi.org/10.1093/eurheartj/ehn569.

[30] Tilg H, Zmora N, Adolph TE et al. The intestinal microbiota fuelling metabolic inflammation. Nat Rev Immunol. 2020; 20:40-54. https://doi.org/10.1038/s41577-019-0198-4.

[31] Fassatoui M, Lopez-Siles M, DA D-R et al. Gut microbiota imbalances in Tunisian participants with type 1 and type 2 diabetes mellitus. Biosci Rep. 2019;39:BSR20182348. Published 2019 Jun 18. https://doi.org/10.1042/BSR20182348.

[32] Letchumanan G, Abdullah N, Marlini M et al. Gut microbiota composition in prediabetes and newly diagnosed type 2 diabetes: A systematic review of observational studies. Front Cell Infect Microbiol. 2022;12:943427. https://doi.org/10.3389/fcimb.2022.943427.

[33] Han CY, Ye XM, Lu JP et al. Effect of Benaglutide on gut microbiota and fecal metabolites in patients with type 2 diabetes mellitus. Diabetes Metab Syndr Obes. 2023; 16:2329-44. https://doi.org/10.2147/DMSO.S418757.

[34] Liang L, Rao E, Zhang X et al. GLP-1 receptor agonists modulate blood glucose levels in T2DM by affecting Faecalibacterium prausnitzii abundance in the intestine. Medicine (Baltimore). 2023;102:e34978. https://doi.org/10.1097/MD.0000000000034978.

[35] Ganesan K, Chung SK, Vanamala J et al. Causal relationship between diet-induced gut microbiota changes and diabetes: A novel strategy to transplant Faecalibacterium prausnitzii in preventing diabetes. Int J Mol Sci. 2018; 19:3720. https://doi.org/10.3390/ijms19123720.

[36] Xu J, Liang R, Zhang W et al. Faecalibacterium prausnitzii-derived microbial anti-inflammatory molecule regulates intestinal integrity in diabetes mellitus mice via modulating tight junction protein expression. J Diabetes. 2020; 12:224-36. https://doi.org/10.1111/1753-0407.12986.