scholarly journals Free Fatty Acids Inhibit Protein Tyrosine Phosphatase 1B and Activate Akt

2013 ◽  
Vol 32 (4) ◽  
pp. 871-879 ◽  
Author(s):  
Eisuke Shibata ◽  
Takeshi Kanno ◽  
Ayako Tsuchiya ◽  
Kohzo Kuribayashi ◽  
Chiharu Tabata ◽  
...  
Marine Drugs ◽  
2019 ◽  
Vol 17 (5) ◽  
pp. 302 ◽  
Author(s):  
Su Hui Seong ◽  
Duc Hung Nguyen ◽  
Aditi Wagle ◽  
Mi Hee Woo ◽  
Hyun Ah Jung ◽  
...  

Hizikia fusiformis (Harvey) Okamura is an edible marine alga that has been widely used in Korea, China, and Japan as a rich source of dietary fiber and essential minerals. In our previous study, we observed that the methanol extract of H. fusiformis and its non-polar fractions showed potent protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase inhibition. Therefore, the aim of the present study was to identify the active ingredient in the methanol extract of H. fusiformis. We isolated a new glycerol fatty acid (13) and 20 known compounds including 9 fatty acids (1–3, 7–12), mixture of 24R and 24S-saringosterol (4), fucosterol (5), mixture of 24R,28R and 24S,28R-epoxy-24-ethylcholesterol (6), cedrusin (14), 1-(4-hydroxy-3-methoxyphenyl)-2-[2-hydroxy -4-(3-hydroxypropyl)phenoxy]-1,3-propanediol (15), benzyl alcohol alloside (16), madhusic acid A (17), glycyrrhizin (18), glycyrrhizin-6’-methyl ester (19), apo-9′-fucoxanthinone (20) and tyramine (21) from the non-polar fraction of H. fusiformis. New glycerol fatty acid 13 was identified as 2-(7′- (2″-hydroxy-3″-((5Z,8Z,11Z)-icosatrienoyloxy)propoxy)-7′-oxoheptanoyl)oxymethylpropenoic acid by spectroscopic analysis using NMR, IR, and HR-ESI-MS. We investigated the effect of the 21 isolated compounds and metabolites (22 and 23) of 18 against the inhibition of PTP1B and α-glucosidase enzymes. All fatty acids showed potent PTP1B inhibition at low concentrations. In particular, new compound 13 and fucosterol epoxide (6) showed noncompetitive inhibitory activity against PTP1B. Metabolites of glycyrrhizin, 22 and 23, exhibited competitive inhibition against PTP1B. These findings suggest that H. fusiformis, a widely consumed seafood, may be effective as a dietary supplement for the management of diabetes through the inhibition of PTP1B.


2018 ◽  
Vol 17 (3) ◽  
pp. 134-139
Author(s):  
R.M. Perez-Gutierrez

Methanol extract from Lippia graveolens (Mexican oregano) was studied in order to identify inhibitory bioactives for protein tyrosine phosphatase 1B (PTP1B). Known flavone as lutein (1), and another flavone glycoside such as lutein-7-o-glucoside (2), 6-hydroxy-lutein-7-ohexoside (3) and lutein-7-o-ramnoide (4) were isolated from methanol extract of aerial parts of the Lippia graveolens. All isolates were identified based on extensive spectroscopic data analysis, including UV, IR, NMR, MS and compared with spectroscopic data previously reported. These flavones were evaluated for PTP1B inhibitory activity. Among them, compounds 1 and 3 displayed potential inhibitory activity against PTP1B with IC50 values of 7.01 ± 1.25 μg/ml and 18.4 μg/ml, respectively. In addition, compound 2 and 4 showed moderate inhibitory activity with an IC50 value of 23.8 ± 6.21 and 67.8 ± 5.80 μg/ml respectively. Among the four compounds, luteolin was found to be the most potent PTP1B inhibitor compared to the positive control ursolic acid, with an IC50 value of 8.12 ± 1.06 μg/ml. These results indicate that flavonoids constituents contained in Lippia graveolens can be considered as a natural source for the treatment of type 2 diabetes.


Author(s):  
Jiajia Zhang ◽  
Ning Wu ◽  
Dayong Shi

Background: The mammalian target of rapamycin (mTOR), protein tyrosine phosphatase 1b (PTP1B) and dipeptidase 4 (DPP4) signaling pathways regulate eukaryotic cell proliferation and metabolism. Previous researches described different transduction mechanisms in the progression of cancer and diabetes. Methodology: We reviewed recent advances in the signal transduction pathways of mTOR, PTP1B and DPP4 regulation and determined the crosstalk and common pathway in diabetes and cancer. Results: We showed that according to numerous past studies, the proteins participate in the signaling networks for both diseases. Conclusion: There are common pathways and specific proteins involved in diabetes and cancer. This article demonstrates and explains the potential mechanisms of association and future prospects for targeting these proteins in pharmacological studies.


Sign in / Sign up

Export Citation Format

Share Document