Low-intensity pulsed ultrasound upregulates pro-myelination indicators of Schwann cells enhanced by co-culture with adipose-derived stem cells.
OBJECTIVE
Peripheral nerve injuries are a common occurrence, resulting in considerable patient suffering; it also represents a major economic burden on society. To improve treatment options following peripheral nerve injuries, scientists aim to find a way to promote Schwann cell (SC) myelination to help nerves to carry out their functions effectively. In this study, we investigated myelination ability of SCs, regulated by co-culture with adipose-derived stem cells (ASCs) or low-intensity pulsed ultrasound (LIPUS), and synergistic effects of combined treatments.


METHODS
Schwann cells were co-cultured with or without ASCs, and either left untreated or treated with LIPUS for 10 min/d for 1, 4 or 7 days. Effects of LIPUS and ASC co-culture on pro-myelination indicators of SCs were analysed by real-time PCR (RT-PCR), Western blotting and immunofluorescence staining (IF).


RESULTS
Our results indicate that ASC-SC co-culture and LIPUS, together or individually, promoted mRNA levels of epidermal growth factor receptor 3 (EGFR3/ErbB3), neuregulin1 (NRG1), early growth response protein 2 (Egr2/Krox20) and myelin basic protein (MBP), with corresponding increases in protein levels of ErbB3, NRG1 and Krox20. Interestingly, combination of ASC-SC co-culture and LIPUS displayed the most remarkable effects.


CONCLUSIONS
We demonstrated that ASCs upregulated pro-myelination indicators of SCs by indirect contact (through co-culture) and that effects could be potentiated by LIPUS. We conclude that LIPUS, as a mechanical stress, may have potential in nerve regeneration with potential clinical relevance.
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China.
Yuan
Y
Yue
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China. 65167950@qq.com.|Oral Implant Center, West China School of Stomatology, Sichuan University, Chengdu, China. 65167950@qq.com.
Xingmei
X
Yang
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Oral Implant Center, West China School of Stomatology, Sichuan University, Chengdu, China.
Liang
L
Zhang
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China.
Xun
X
Xiao
Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA.
Neel R
NR
Nabar
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.
Yunfeng
Y
Lin
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.
Liang
L
Hao
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China.
Dongjiao
D
Zhang
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China.
Jingyi
J
Huo
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China.
Jingle
J
Li
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China.|Oral Implant Center, West China School of Stomatology, Sichuan University, Chengdu, China.
Xiaoxiao
X
Cai
State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China. hxkqwangm@163.com.|Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, China. hxkqwangm@163.com.
Min
M
Wang
D000273:Adipose Tissue / Q000166:cytology* / Q000378:metabolism; D053687:Adult Stem Cells / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D018920:Coculture Techniques; D051767:Early Growth Response Protein 2 / Q000235:genetics; D005260:Female; D004676:Myelin Basic Protein / Q000235:genetics; D009186:Myelin Sheath / Q000235:genetics*; D020890:Neuregulin-1 / Q000235:genetics; D059348:Peripheral Nerve Injuries / Q000235:genetics / Q000628:therapy*; D012333:RNA, Messenger / Q000235:genetics; D017207:Rats, Sprague-Dawley; D020893:Receptor, ErbB-3 / Q000235:genetics; D012583:Schwann Cells / Q000166:cytology / Q000378:metabolism*; D014464:Ultrasonic Therapy / Q000379:methods; D000069453:Ultrasonic Waves; D015854:Up-Regulation
D051767:Early Growth Response Protein 2; D004676:Myelin Basic Protein; D020890:Neuregulin-1; D012333:RNA, Messenger; D020893:Receptor, ErbB-3