Team:ShanghaiTech China/Description
Our main goal features utilizing the intestinal probiotics who can synthesize and release N-palmitoyl serinol to promote the body insulin level, which will greatly benefit the patient suffering from diabetes.
INSULEN:
An Intelligent N-palmitoyl-serinol System Utilizing Light-controlled Enterobacterium for diabetic therapy
Type 2 diabetes (T2D) has become an increasing public health problem worldwide. Its existing treatments, including insulin/GLP-1 injections and other drugs, are inconvenient and expensive. N-acyl amides are a family of small molecules secreted by resident enterobacteria to relieve T2D. Thus, ShanghaiTech_China team aims to engineer a smart enterobacteria system that can be fed in glucose values to control the production of N-acyl amides for diabetic alleviation. Using E. coli as a demo, we cloned the synthase for N-palmitoyl serinol, the most potent group in N-acyl amides, into the E. coli expressing plasmid under a light-controllable promoter. Then, we designed software and LED device that can accept glucose signals from T2D patients to control the synthase expression, which leads to the production of the therapeutic molecule. Together, with INSULEN, we offered a convenient, cheap and smart way to battle against T2D and proved it in principle.
Why choose diabetes type II?
Diabetes is one of the largest global health emergencies of the 21st century. Globally, diabetes is considered as one of the four major noncommunicable diseases (NCDs) account for over 80% of all premature NCD deaths and the number of people with diabetes is increasing significantly.
According to the 2018-2023 China diabetes drug industry demand and investment forecast analysis report released by cutting-edge industry research institute. In 2017, the number of people suffering from diabetes was 425 million, and it is estimated that by 2045, the number of people with diabetes will exceed 600 million, becoming an important disease threatening people's health.
Why use N-palmitoyl serinol?
To expound the function ofN-palmitoyl serinol, let us start from GPCR. In eukaryotes, the largest membrane receptor family GPCR is associated with diabetes, obesity, cancer and other diseases, and considered to be the key medium of host-microbe interaction in the human microbiome. Among them, GPR119 is a widely recognized GPCR target highly correlated with diabetes as well as obesity and found to have a significant effect on the steady-state of glucose [2] [4]. GPR119s are mainly distributed in the intestinal mucosa where they interreact with endogenous GPR119 ligands [5].
N-acyl amide is a group of GPR119’s ligands. And N-palmitoyl serinol is one in this group with a stronger effect of promoting the production of insulin [1]. As it has been proved that the N-palmitoyl serinol has the same effect as the endogenous ligands [3], we want to build an autonomous N-palmitoyl serinol producing system in patients’ intestines.
Why haven't we used N-palmitoyl serinol yet?
Although the newly found substance has great potential in curing diabetes, it truly has some limitations by now, which is also the main question we want to settle down. First, N-palmitoyl serinol is pretty new for clinical usage and has not come into public horizons by now--all trials are lab-based. Second, it is not easy to control the production of N-palmitoyl serinol by traditional means. As a solution, we want to try regulatory element this time.
How to control the circuit?
We are also eager to figure out how to control the secretion of the small molecule intelligently by engineering the E.coli bacteria. The secretion of the specific molecule can be controlled through various ways. In the end, we selected the pDawn system which induces gene expression in a light-activated manner, and the control lights can be easily programmed.
What are we doing?
As the sequence of N-acyl synthase (NAS) has been deposited, we synthesized the coding sequence and subcloned it into the pDawn plasmid.
Our work was to determine the relationship between induction conditions and N-palmitoyl serinol concentration to control the concentration in a programmable way. We set up a series of induction factor gradient, such as different light durations and the bacteria density.
We are also establishing an intelligent control system. By using information technology, we use Bluetooth to connect the blood sugar detector, INSULEN App on smartphone and the 'INSULEN Waist Pack' device. And the system can automatically regulate the emission of near-infrared to control the NAS expression.
References
[1] Bradshaw, H. B. & Walker, J. M. The expanding field of cannabimimetic and related lipid mediators. Br J Pharmacol 144, 459-465, doi:10.1038/sj.bjp.0706093 (2005).[2] Cohen, L. J. et al. Commensal bacteria make GPCR ligands that mimic human signalling molecules. Nature 549, 48-+, doi:10.1038/nature23874 (2017).
[3] Cohen, L. J. et al. Functional metagenomic discovery of bacterial effectors in the human microbiome and isolation of commendamide, a GPCR G2A/132 agonist. Proc Natl Acad Sci U S A 112, E4825-4834, doi:10.1073/pnas.1508737112 (2015).
[4] Lauffer, L. M., Iakoubov, R. & Brubaker, P. L. GPR119 is essential for oleoylethanolamide-induced glucagon-like peptide-1 secretion from the intestinal enteroendocrine L-cell. Diabetes 58, 1058-1066, doi:10.2337/db08-1237 (2009).
[5] Overton, H. A. et al. Deorphanization of a G protein-coupled receptor for oleoylethanolamide and its use in the discovery of small-molecule hypophagic agents. Cell Metab 3, 167-175, doi:10.1016/j.cmet.2006.02.004 (2006).