Page 1 - H. Cell signaling

Arginase II down regulation recovers Ca /CaMKII-Akt-eNOS signaling and
2+
vascular homeostasis in p32 over expressed.
Bon-hyeock Koo, Sungwoo Ryoo
Department of Biology, College of Natural Sciences, Kangwon National University, Chuncheon 200-701, Republic of Korea

BACKGROUND Methods

● Maintaining vascular homeostasis is important physiologically for vascular systems. ● Electron microscopy (EM)
● Intracellular Ca 2+ signaling between mitochondria and cytosol which is regulated by mitochondrial p32 ● Mitochondrial fractionation
and their mechanism is important for vascular homeostasis.
● Immunofluorescence staining and imaging
● Among the various function of p32, our previous research is found that p32 is possible to uptake from
cytosol to mitochondria. In this study shown that localization of artificially expressed p32 is placed in ● Preparation of p32-expressing adenovirus
mitochondria and ER and also has a Ca 2+ movement function.
● Confocal microscopy and flow cytometry
● p32 overexpression decrease CaMKII/Akt/eNOS signaling and disrupts vascular homeostasis via Ca 2+
● Measurement of NO and ROS
movement from cytosol to mitochondria and ER but arginase II down regulation can alleviate their
signaling and vascular homeostasis ● Aortic vascular tension assay
AIM

The target organelles of overexpressed p32 and determined whether the p32 involved in
the regulation of cytosolic Ca 2+ was associated with Ca 2+ -dependent eNOS activation?

RESULTS

Cell count

Cell count

Fig 2. Over-expressed p32 has their function which is Ca 2+ uptake
from cytosol to ER and mitochondria.

Fig 1. p32 over expression through adenovirus increases
p32 level in not only mitochondria but endoplasmic reticulum.

Fig 4. Although p32 adenovirus
increased p32 expression, arginase
II down-regulation activates CaMKII-
Fig 3. Up-regulated p32 induces to decrease NO production and increase ROS generation by inactivating eNOS signaling by reducing p32
CaMKII-Akt-eNOS signaling axis, therefore disrupts vascular homeostasis. level.
CONCLUSION REFERENCES

● p32 over expression decrease CaMKII/Akt/eNOS signaling and disrupts vascular Koo BH, et al, Arginase II activity regulates cytosolic Ca 2+ level in a
homeostasis via Ca 2+ movement from cytosol to mitochondria and ER p32-dependent manner that contributes to Ca 2+ -dependent
vasoconstriction in native low-density lipoprotein-stimulated
vascular smooth muscle cells. Exp Mol Med. 2019 Jun3
● Arginase II down regulation can alleviate their signaling and vascular homeostasis
Koo BH, et al. Arginase II Contributes to the Ca 2+ /CaMKII/eNOS
● Comprehensive relationship of arginase II and p32 will be help to find novel Axis by Regulating Ca 2+ Concentration Between the Cytosol and
Mitochondria in a p32-Dependent Manner. J Am Heart Assoc.
therapeutics in various vascular diseases. 2018 Sep 18