Page 11 - A. Aging

Choline Acetyltransferase induces the functional regeneration of salivary gland
in aging mouse model
Nguyen Khanh Toan and Sang-Gun Ahn
Department of Pathology, School of Dentistry, Chosun University, Kwangju, 61452, Republic of Korea

BACKGROUND
Salivary gland dysfunction causes due to radiation, medications, not be significantly impacted by age. Although conflicted results are
autoimmune or metabolic diseases, and aging-related degeneration are remaining, recently, a meta-analysis study suggested that there is
the common etiology for salivary gland impairment. Aging leads to
structural changes in the salivary gland as the replacement of acinar an age-related reduction in saliva secretion in the resting and
cells by fat and fibrous tissues in the submandibular, parotid, and minor stimulated saliva in elder adults, compared with young adults. In
glands. Since saliva is primary produced in the acinar cells, theses additional study, population-based research also demonstrated to
salivary gland degeneration can lead to hyposalivation in the elders. diminish in salivary gland size, saliva volume, and saliva
Moreover, several studies showed the correlation between aging and
reduced components in saliva, including digestive enzymes, hormones, components with increasing age. However, although the aging has
antimicrobial substances, growth factors, and antioxidants. The been reported to decline salivary gland function, the fundamental
reduction of saliva has severe effects on the patient’s quality-of-life as mechanism is not clear.
this deteriorates taste perception, swallowing, and speech performance.
It also leads to the increase in the incidence of dental caries, mucosal
atrophy, and ulceration, in addition to an overall reduction of immune AIM
response against infectious agents. More recent research suggested
that saliva output in the major glands may diminish with increasing age This study aimed to investigate the impact of aging in the salivary
and occur in the viscoelasticity of saliva with aging in submandibular gland by metabolomics approach in the extensive aging mice
and sublingual glands. In contrast to the above, some study suggests
that the clinically significant declines of stimulated saliva flow rate may model, SAMP1/Klotho -/- mice.
METHODS

Metabolome profiles of mouse submandibular salivary gland tissue by CE-TOFMS analysis
Metabolome analyses were performed for 3 samples of mouse submandibular salivary gland tissue (SAMP1/kl wild type, SAMP1/kl-/- 4 weeks
old, and SAMP1/kl-/- 8 weeks old) using Capillary Electrophoresis Time-of-Flight Mass Spectrometry (CE-TOFMS) in two modes for cationic and
anionic metabolites. The samples were mixed with 50% acetonitrile in water (v/v) containing internal standards (20 μM for cation and 5 μM for
anion measurement) and homogenized by a homogenizer (1,500 rpm, 120 sec × 4 times). The supernatant (400 μL × 2) was then filtrated
through a 5-kDa cut-off filter (ULTRAFREE-MC-PLHCC, Human Metabolome Technologies, Yamagata, Japan) to remove macromolecules.
RESULTS

Figure 1 Figure 2 Figure 3

Figure 4 Figure 5 Figure 6

CONCLUSION REFERENCES ACKNOWLEDGEMENTS

• SAMP1/kl-/- mice exhibits salivary 1. Abiko,Y., Nishimura, M., & Kaku, T. (2003). This work was supported by the National
gland dysfunction, due to the Defensins in saliva and the salivary Research Foundation of Korea (NRF) grant
alteration in Acetylcholine glands. Medical electron microscopy: official funded by the Korean government (MSIT)
journal of the Clinical Electron Microscopy
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• ChAT can regulate functional 2. Affoo, R. H., Foley, N., Garrick, R., Siqueira, W.
L., & Martin, R. E. (2015). Meta-Analysis of Contact information
salivary gland markers Salivary Flow Rates in Young and Older
• ChAT gene transfer can induce the Adults. Journal of the American Geriatrics Sang-Gun Ahn, PhD,
salivary glands regeneration and Society, 63(10), 2142–2151. Department of Pathology, School of Dentistry,
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Sciences, 694, 17–23. Gwangju, Republic of Korea, 61452