Tissue non-specific alkaline phosphatase mediates the accumulation of cholesterol esters in the murine Y1 adrenal cortex cell line

Background: Alkaline Phosphatase (AP) is a physiologically important metalloenzyme that belongs to a large family of ectonucleotidase enzymes. Over-expression of tissue non-specific alkaline phosphatase has been linked with ectopic calcification including vascular and aortic calcification. In Vascular Smooth Muscles Cells (VSMCs), the high level of Reactive Oxygen Species (ROS) resulted in the up-regulation of TNAP. Accordingly, there is a need to identify highly potent and selective inhibitors of APs for treatment of disorders related to hyper activity of APs. Methods: Herein, a series of coumarinyl alkyl/aryl sulfonates (1-40) with known Reactive Oxygen Species (ROS) inhibition activity, was evaluated for alkaline phosphatase inhibition against human Tissue Non-specific Alkaline Phosphatase (hTNAP) and Intestinal Alkaline Phosphatase (hIAP). Results: With the exception of only two compounds, all other compounds in the series exhibited excellent AP inhibition. For hIAP and hTNAP inhibition, IC50 values were observed in the range 0.62-23.5 µM, and 0.51-21.5 µM, respectively. Levamisole (IC50 = 20.21 ± 1.9 µM) and Lphenylalanine (IC50 = 100.1 ± 3.15 µM) were used as standards for hIAP and hTNAP inhibitory activities, respectively. 4-Substituted coumarinyl sulfonate derivative 23 (IC50 = 0.62 ± 0.02 µM) was found to be the most potent hIAP inhibitor. Another 4-substituted coumarinyl sulfonate derivative 16 (IC50 = 0.51 ± 0.03 µM) was found to be the most active hTNAP inhibitor. Some of the compounds were also found to be highly selective inhibitors of APs. Detailed Structure-Activity Relationship (SAR) and Structure-Selectivity Relationship (SSR) analysis were carried out to identify structural elements necessary for efficient and selective AP inhibition. Molecular modeling and docking studies were carried out to rationalize the most probable binding site interactions of the inhibitors with the AP enzymes. In order to evaluate drug-likeness of compounds, in silico ADMETox evaluation was carried out, most of the compounds were found to have favorable ADME profiles with good predicted oral bioavailability. X-ray crystal structures of compounds 38 and 39 were also determined. Conclusion: Compounds from this series may serve as lead candidates for future research in order to design even more potent, and selective inhibitors of APs.

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Opposite correlation of 25-hydroxy-vitamin D- and 1,25-dihydroxy-vitamin D-metabolites with gestational age, bone- and lipid-biomarkers in pregnant women

Scientific Reports ◽

10.1038/s41598-021-81452-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Oleg Tsuprykov ◽

Saban Elitok ◽

Claudia Buse ◽

Chang Chu ◽

Bernhard Karl Krämer ◽

...

Keyword(s):

Vitamin D ◽

Alkaline Phosphatase ◽

Pregnant Women ◽

Clinical Chemistry ◽

Water Soluble ◽

Target Cells ◽

Vitamin D Metabolites ◽

Specific Alkaline Phosphatase ◽

Bone Specific Alkaline Phosphatase ◽

Group B

Abstract25-Hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D (1,25(OH)2D) need to be bound to carrier proteins to be transported to their target cells. The majority of either 25OHD or 1,25(OH)2D is bound to vitamin D-binding protein (DBP), a smaller fraction is bound to albumin and only very small amounts of 25OHD or 1,25(OH)2D are free. Albumin-bound 25OHD or 1,25(OH)2D is relatively easily available after dissociation from albumin. Thus, the sum of free and albumin-bound forms is called bioavailable 25OHD and bioavailable 1,25(OH)2D. Total 25OHD and 1,25(OH)2D are defined as the sum of free, albumin-bound and DBP-bound 25OHD and 1,25(OH)2D, respectively. This cross-sectional study in 427 pregnant women compared the correlation of the six vitamin D compounds with biomarkers of bone health, lipid metabolism, kidney function, endocrine parameters, and group B water-soluble vitamins. Among the 25OHD metabolites analysed, total 1,25(OH)2D showed clearly the best correlation with calcium, bone-specific alkaline phosphatase, adiponectin, LDL, HDL, urea, thyroxine, and group B water-soluble vitamins. When comparing the three 25OHD metabolites, both free 25OHD and bioavailable 25OHD showed overall good correlations with calcium, bone-specific alkaline phosphatase, adiponectin, LDL, HDL, urea, thyroxine, triiodothyronine, and group B water-soluble vitamins, The correlations of 1,25(OH)2D and 25OHD metabolites went always in opposite directions. Only PTH correlates always inversely with all six vitamin D compounds. In conclusion, free 25(OH)D and bioavailable 25(OH)D are more precise determinants of the vitamin D status than total 25(OH)D in normal pregnancy, whereas total 1,25(OH)2D is superior to free and bioavailable 1,25(OH)2D. Except for PTH, correlations of 25(OH)D and 1,25(OH)2D metabolites with typical clinical chemistry readouts go in opposite directions.

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Acute Response of Sclerostin to Whole-body Vibration with Blood Flow Restriction

International Journal of Sports Medicine ◽

10.1055/a-1422-3376 ◽

2021 ◽

Author(s):

Kyle S Gapper ◽

Sally Stevens ◽

Rona Antoni ◽

Julie Hunt ◽

Sarah J Allison

Keyword(s):

Alkaline Phosphatase ◽

Blood Flow ◽

Whole Body Vibration ◽

Blood Flow Restriction ◽

Whole Body ◽

Specific Alkaline Phosphatase ◽

Body Vibration ◽

Bone Specific Alkaline Phosphatase ◽

Flow Restriction ◽

Acute Response

AbstractBlood flow restriction may augment the skeletal response to whole-body vibration. This study used a randomised, crossover design to investigate the acute response of serum sclerostin and bone turnover biomarkers to whole-body vibration with blood flow restriction. Ten healthy males (mean±standard deviation; age: 27±8 years) completed two experimental conditions separated by 7 days: (i) whole-body vibration (10 1-minute bouts of whole-body vibration with 30 s recovery) or (ii) whole-body vibration with lower-body blood flow restriction (10 cycles of 110 mmHg inflation with 30 s deflation during recovery). Fasting blood samples were obtained immediately before and immediately after exercise, then 1 hour, and 24 hours after exercise. Serum samples were analysed for sclerostin, cross-linked C-terminal telopeptide of type I collagen, and bone-specific alkaline phosphatase. There was a significant time × condition interaction for bone-specific alkaline phosphatase (p=0.003); bone-specific alkaline phosphatase values at 24 hours post-exercise were significantly higher following whole-body vibration compared to combined whole-body vibration and blood flow restriction (p=0.028). No significant time × condition interaction occurred for any other outcome measure (p>0.05). These findings suggest that a single session of whole-body vibration combined with blood flow restriction does not significantly affect serum sclerostin or bone turnover biomarkers.

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