2.Preparation and preliminary biological evaluation of 177Lu-NOTATATE
Chengrun ZENG ; Yuxiao XIA ; Wenhui FU ; Yingwei WANG ; Zibo LI ; Yue CHEN
Chinese Journal of Nuclear Medicine and Molecular Imaging 2021;41(11):670-675
Objective:To explore the optimal labeling conditions of 177Lu-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (NOTA)- D-Phe1-Tyr3-Thr8-octreotide (TATE), and evaluate its biodistribution and imaging characteristics in mice. Methods:The reaction temperature, pH, reaction time and other labeling conditions were changed to realize the rapid labeling of NOTATATE by 177Lu. The optimal labeling conditions, radiochemical purity, in vitro stability, plasma protein binding rate, and lipid-water partition coefficient were determined. Twenty-four normal KM mice were divided into 6 groups by random number table method. After injected with 3.7 MBq 177Lu-NOTATATE through tail vein, they were sacrificed at 0.5, 1, 4, 24 h and 4, 6 d respectively to research the biological distribution (injection dose rate per gram of tissue percentage, %ID/g). Six normal mice were randomly divided into 2 groups and injected with 11.1 MBq 177Lu-NOTATATE and 177Lu-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)TATE, respectively. SPECT planar imaging was performed at 1, 2, 3 h after injection. Another 8 mice were divided into 4 groups, injected with 3.7, 7.4, 18.5 MBq 177Lu-NOTATATE and saline respectively for an acute toxicity test. Results:At pH 5 and reaction temperature between 95 ℃ and 100 ℃ for 15 min, the labeling rate could reach more than 98%. After being placed in human serum for 24 h, the radiochemical purity was still higher than 95%. The plasma protein binding rate of 177Lu-NOTATATE was (58.6±1.9)% and the lipid-water partition coefficient was 0.048±0.014. In normal mice, the concentration of radioactivity is mainly in the liver, kidney and spleen, especially in the kidney (up to (29.120±1.204) %ID/g after 0.5 h of injection), which is less distributed in the blood and excreted rapidly. Compared with 177Lu-DOTATATE, 177Lu-NOTATATE was excreted faster by the kidney. The toxicity study results revealed that no damage was observed in mice of each group, and no obvious damage or inflammatory changes were observed in organ tissue sections. Conclusions:The optimal labeling condition of 177Lu-NOTATATE were determined in this study. The physical, chemical, and biological properties of 177Lu-NOTATATE were proved to be good and safe, and it was excreted faster by the kidney than 177Lu-DOTATATE. The results of this study lay a foundation for further clinical transformation research.
3.Synthesis and biological evaluation of a series of 2-(((5-akly/aryl-1-pyrazol-3-yl)methyl)thio)-5-alkyl-6-(cyclohexylmethyl)-pyrimidin-4(3)-ones as potential HIV-1 inhibitors.
Yumeng WU ; Chengrun TANG ; Ruomei RUI ; Liumeng YANG ; Wei DING ; Jiangyuan WANG ; Yiming LI ; Christopher C LAI ; Yueping WANG ; Ronghua LUO ; Weilie XIAO ; Hongbing ZHANG ; Yongtang ZHENG ; Yanping HE
Acta Pharmaceutica Sinica B 2020;10(3):512-528
A series of 2-(((5-akly/aryl-1-pyrazol-3-yl)methyl)thio)-5-alkyl-6-(cyclohexylmethyl)-pyrimidin-4(3)-ones were synthesized and their anti-HIV-1 activities were evaluated. Most of these compounds were highly active against wild-type (WT) HIV-1 strain (IIIB) with EC values in the range of 0.0038-0.4759 μmol/L. Among those compounds, had an EC value of 3.8 nmol/L and SI (selectivity index) of up to 25,468 indicating excellent activity against WT HIV-1. anti-HIV-1 activity and resistance profile studies suggested that compounds and displayed potential anti-HIV-1 activity against laboratory adapted strains and primary isolated strains including different subtypes and tropism strains (ECs range from 4.3 to 63.6 nmol/L and 18.9-219.3 nmol/L, respectively). On the other hand, it was observed that those two compounds were less effective with EC values of 2.77 and 4.87 μmol/L for HIV-1A (K103N + Y181C). The activity against reverse transcriptase (RT) was also evaluated for those compounds. Both and obtained sub-micromolar IC values showing their potential in RT inhibition. The pharmacokinetics examination in rats indicated that compound has acceptable pharmacokinetic properties and bioavailability. Preliminary structure-activity relationships and molecular modeling studies were also discussed.