Header Image
Header Image

Overview

Rapid urbanisation has been a critical feature of India's development. People have increasingly migrated from rural areas to cities for better economic opportunities. This shift has led to changes in living conditions, employment patterns, and social dynamics. Modern dietary changes, sedentary lifestyle, stress and anxiety, increased usage of certain medications and deteriorating environmental conditions have adversely affected the gastrointestinal health of the world's population. These changes and new adaptations have been significantly affecting digestive health and the gut brain axis causing diverse gastrointestinal disorders like Irritable Bowel syndrome, Inflammatory Bowel Disease, Gastritis, Celiac disease, Diverticulitis, etc.

One such disease is Irritable Bowel Syndrome (IBS). IBS is a condition characterized by abdominal pain, bloating or other discomfort occurring in association with a disturbed bowel pattern in the absence of organic causes that can be detected by routine medical tests. A growing number of people suffer from IBS, with an estimated 5.8%-17.5% prevalence, especially in females. IBS causes a tremendous decline in the health-related quality of life and brings a considerable socioeconomic burden of up to $19 billion. IBS can be diagnosed using Rome III criteria and subclassified according to patients' predominant stool pattern using the Bristol Stool Form Scale as either constipation- or diarrhea-predominant, mixed type, or unsubtyped/unclassified (ie, insufficient abnormality of stool consistency to meet criteria for the other IBS subtypes; ). Up to 40% of patients with IBS have diarrhea as the predominant bowel symptom (IBS-D subtype). There are 4 different subtypes in IBS which are as follows:

IBS-D Image

IBS with Diarrhoea (IBS-D)

Hard/lumpy stools < 25% bowel movement
Loose/watery stools > 25% bowel movements.

IBS-C Image

IBS with Constipation (IBS-C)

Hard/lumpy stools > 25% bowel movement
Loose/watery stools < 25% bowel movements.

IBS-D Image IBS-C

Mixed IBS (IBS-M)

Hard/lumpy stools > 25% bowel movement
Loose/watery stools > 25% bowel movements

IBS-C Image

Unsubtyped IBS

Abnormality of stool consistency to meet criteria for IBS-C, IBS-D, IBS-M

Fig 1: Lorem Ipsum

Fig 1: "IBS-D" is the most common type of IBS, followed by "IBS-C". "IBS-M" is the third most common type, and "IBS-U" is the least common type.

IBS-D

IBS-D is associated with predominant symptoms of diarrhoea alongside abdominal discomfort, pain, sudden urges and gassiness. People suffering from IBS-D have no control over the bowel movements. With extensive literature review, it has been found that the Serotonin transporter (SERT) gene in humans is downregulated, hence resulting in an increased level of serotonin in the gut. According to literature, there is evidence indicating that serotonin present in the gastrointestinal tract can influence gut motility by interacting with serotonin receptors known as 5-HT3 and 5-HT4. Elevated levels of serotonin in the gut have been associated with an increase in gut motility, potentially leading to the occurrence of diarrhoea.

Existing medications and their side-effects

Current treatment methods for IBS-D, such as serotonin receptor inhibitors, diarrheal inhibitors, and antidepressants, often treat symptomatic conditions and come with severe side effects like constipation, nausea and changes in appetite. Based on the sources we have encountered, it appears that the treatment options for irritable bowel syndrome with diarrhea (IBS-D), particularly newer ones, suffer from inadequate accessibility and affordability. These treatments are frequently excluded from medical insurance plans due to the perception that IBS-D is primarily a mental health issue, resulting in a lack of seriousness towards its medical management

  • Changes in appetite
  • Mixed IBS (IBS-M) with elevation of symptoms by using SSRIs
  • Nausea
  • Constipation

There is a significant scientific need for improved treatment options for IBS-D. The existing medications have limitations and side effects, making it necessary to explore alternative approaches. By utilizing synthetic biology and developing a probiotic- based solution, we aim to address this scientific need biomedical concern by offering a novel, safe and potentially more effective treatment modality.

AnthraFelix

ANTHRAFELIX, Our project proposes an innovative solution: AnthraFelix, a genetically engineered probiotic therapeutic for IBS-D. This probiotic is designed to respond to elevated serotonin levels in the colon by converting the excess serotonin into melatonin.

Mechanism of action

Our probiotic will be delivered as a colon targeted pill. The pill on reaching the colon, releases the genetically engineered E coli Nissle 1917. The bacteria will take up the excess serotonin through a heterologously expressed Serotonin Transporter of bacterial origin. This probiotic also possess a gene, which encodes a Quorum Sensing molecule called LasR. LasR responds to increasing serotonin levels within the colon. When the concentration of serotonin reaches a certain threshold, the LasR molecule binds to Serotonin in a concentration dependant manner. As a result, the LasR+Serotonin complex activates the LasI promoter, initiating the transcription process of specific genes. These genes encode enzymes that are responsible for converting serotonin into melatonin, and they are SNAT (Serotonin N-Acetyl Transferase) and COMT (Caffeic Acid O Methyl Transferase) which convert Serotonin to N-acetyl Serotonin and then to Melatonin respectively.

Why is AnthraFelix better than the existing therapeutics?

Serotonin translocation occurs by the serotonin reuptake transporter (SERT) to maintain the appropriate level of serotonin in the gut. SERT takes serotonin into enterocytes, where it is catabolized by monoamine oxidases. So, any changes in SERT transcription will alter available serotonin in the gut. In patients with IBS, there is a decreased transcription of SERT, resulting in elevated serotonin levels, which ultimately causes diarrhea and discomfort, which is transmitted by serotonin through the gut-brain axis. Higher 5-HT availability is commonly associated with depressed SERT mRNA in patients with IBS compared with healthy controls, thus playing an important role in the pathogenesis of IBS. SERT gene expression is affected by various factors such as SERT gene polymorphisms, microRNAs, immunity and inflammation, gut microbiota, and growth factors. Thus regulation of SERT gene expression to regulate serotonin levels become complex. Existing therapeutics manipulate the serotonergic mechanisms within the gut targeting serotonin receptors which leads to severe side effects but don't reduce the serotonin levels in the gut. Thus there is a need for a non-invasive mechanism to reduce serotonin levels. Our engineered bacteria take up excess serotonin through a bacterial serotonin transporter and convert it into melatonin which is a reliever of IBS symptoms, thus easing the disease severity.

Why Serotonin?

How is Melatonin an effective solution?

Melatonin is a perfect candidate for IBS treatment based on the following considerations:

  1. It has analgesic effects, which may help to alleviate abdominal pain and influence the sensation of abdominal distention in IBS patients.
  2. It has regulatory effects on gastrointestinal tract motility and sensation, which may improve bowel habits and alleviate abdominal pain or distention in IBS patients.
  3. It could have a sleep-promoting effect which may be useful in treating the sleep disturbance of IBS patients.
  4. It has mood regulation and anti-stress effects, which could help alleviate the abnormal psychological parameters observed in IBS patients.

Thus, we believe that melatonin might serve several aspects of the IBS treatment strategy because it targets not only the psychological component, i.e., stress, anxiety, depression, and sleep disorder but also the peripheral elements of abnormal bowel sensation and motility. These valuable properties of melatonin make our Probiotic much more effective, safe, and practical.

Commensal bacteria do not create
any problem in the gut
No immune response as we are
using a commensal bacteria

Improves overall quality of life physically and mentally

Melatonin have analgesic effect, regulates GI tract's motility, mood regulation and other positive effects.

Reducing serotonin levels helps relieve the symptoms.>

Since the serotonin reuptake transporter is reduced in the epithelium of active Crohn's disease and ulcerative colitis and also, Serotonin plays a crucial role in the maintenance of Inflammatory state in Crohn’s Disease, AnthraFelix is also helpful in treating these Gastrointestinal disorders

References

  1. Vahora, I. S., Tsouklidis, N., Kumar, R., Soni, R., & Khan, S. (2020). How Serotonin Level Fluctuation Affects the Effectiveness of Treatment in Irritable Bowel Syndrome. Cureus, 12(8), e9871.
    https://doi.org/10.7759/cureus.9871

  2. Siah, K. T., Wong, R. K., & Ho, K. Y. (2014). Melatonin for the treatment of irritable bowel syndrome. World journal of gastroenterology, 20(10), 2492-2498.
    https://doi.org/10.3748/wjg.v20.i10.2492

  3. Byeon, Y., Back, K. Melatonin production in Escherichia coli by dual expression of serotonin N-acetyltransferase and caffeic acid O-methyltransferase. Appl Microbiol Biotechnol 100, 6683-6691 (2016).
    https://rdcu.be/dcpsR

  4. Knecht, L. D., O'Connor, G., Mittal, R., Liu, X. Z., Daftarian, P., Deo, S. K., & Daunert, S. (2016). Serotonin Activates Bacterial Quorum Sensing and Enhances the Virulence of Pseudomonas aeruginosa in the Host. EBioMedicine, 9, 161-169.
    https://doi.org/10.1016/j.ebiom.2016.05.037

  5. Jin, D. C., Cao, H. L., Xu, M. Q., Wang, S. N., Wang, Y. M., Yan, F., & Wang, B. M. (2016). Regulation of the serotonin transporter in the pathogenesis of irritable bowel syndrome. World journal of gastroenterology, 22(36), 8137–8148.
    https://doi.org/10.3748/wjg.v22.i36.8137

  6. Canavan, C., West, J., & Card, T. (2014). The epidemiology of irritable bowel syndrome. Clinical epidemiology, 6, 71–80.
    https://doi.org/10.2147/CLEP.S40245

  7. Tada, Y., Ishihara, S., Kawashima, K., Fukuba, N., Sonoyama, H., Kusunoki, R., Oka, A., Mishima, Y., Oshima, N., Moriyama, I., Yuki, T., Ishikawa, N., Araki, A., Harada, Y., Maruyama, R., & Kinoshita, Y. (2016). Downregulation of serotonin reuptake transporter gene expression in healing colonic mucosa in presence of remaining low-grade inflammation in ulcerative colitis. Journal of gastroenterology and hepatology, 31(8), 1443–1452.
    https://doi.org/10.1111/jgh.13268

  8. Jørandli, J. W., Thorsvik, S., Skovdahl, H. K., Kornfeld, B., Sæterstad, S., Gustafsson, B. I., Sandvik, A. K., & van Beelen Granlund, A. (2020). The serotonin reuptake transporter is reduced in the epithelium of active Crohn's disease and ulcerative colitis. American journal of physiology. Gastrointestinal and liver physiology, 319(6), G761–G768.
    https://doi.org/10.1152/ajpgi.00244.2020

  9. Pergolizzi, S., Alesci, A., Centofanti, A., Aragona, M., Pallio, S., Magaudda, L., Cutroneo, G., & Lauriano, E. R. (2022). Role of Serotonin in the Maintenance of Inflammatory State in Crohn's Disease. Biomedicines, 10(4), 765.
    https://doi.org/10.3390/biomedicines10040765

  10. Khan WI. The Role of 5-HT Dysregulation in Inflammatory Bowel Disease. Gastroenterol Hepatol (N Y). 2013 Apr;9(4):259-61. PMID: 24711774; PMCID: PMC3977648.

  11. Kiratisin, P., Tucker, K. D., & Passador, L. (2002). LasR, a transcriptional activator of Pseudomonas aeruginosa virulence genes, functions as a multimer. Journal of bacteriology, 184(17), 4912–4919.
    https://doi.org/10.1128/JB.184.17.4912-4919.2002

  12. Schuster, M., Urbanowski, M. L., & Greenberg, E. P. (2004). Promoter specificity in Pseudomonas aeruginosa quorum sensing revealed by DNA binding of purified LasR. Proceedings of the National Academy of Sciences, 101(45), 15833-15839.
    https://doi.org/10.1073/pnas.0407229101

  13. Tsai, C. S., & Winans, S. C. (2010). LuxR-type quorum-sensing regulators that are detached from common scents. Molecular microbiology, 77(5), 1072–1082.
    https://doi.org/10.1111/j.1365-2958.2010.07279.x

  14. Fung, T. C., Vuong, H. E., Luna, C. D. G., Pronovost, G. N., Aleksandrova, A. A., Riley, N. G., Vavilina, A., McGinn, J., Rendon, T., Forrest, L. R., & Hsiao, E. Y. (2019). Intestinal serotonin and fluoxetine exposure modulate bacterial colonization in the gut. Nature microbiology, 4(12), 2064–2073.
    https://doi.org/10.1038/s41564-019-0540-4

Footer with Sponsors