Hypoxia
Promotes Proliferation and Inhibits
Apoptosis of Pulmonary Arterial Smooth Muscle Cells via
Modulating TRPC6
Na Qiao1#, Jiaqiang Pan1#,
Hanming Chen1, Zhenlong Kang1, Congying Pang1,
Bingxian Liu1, Qiwen Zeng1, Khalid Mehmood2,
Rana Muhammad Bilal2, Riaz Hussain Pasha3,
Qudratullah4, Zhaoxin Tang1* and Ying Li1*
1College
of Veterinary, South China Agricultural University, Guangzhou,
510642, China; 2Faculty of
veterinary and Animal Sciences, The Islamia University of
Bahawalpur, 63100, Pakistan; 3Department of Veterinary
Biomedical Sciences (Histology), Faculty of Veterinary and Animal
Sciences, PMAS- Arid Agriculture University Rawalpindi, Pakistan;
4Department of Surgery and Pet Center, Cholistan
University of Veterinary and Animal Sciences, Bahawalpur, 63100,
Pakistan; #Na Qiao and Jiaqiang Pan have contributed
equally to this work and shared as the co-first author.
*Corresponding author:
Prof. Zhaoxin Tang: tangzx@scau.edu.cn;
Prof. Ying Li: lying@scau.edu.cn
Abstract
Ascites syndrome (AS) is a common nutritional
metabolic disease in broilers that results in major loss to the breeding
industry. The occurrence of AS is closely related to the abnormal proliferation
of pulmonary artery smooth muscles cells (PASMCs) caused by hypoxia. The
transient receptor potential cation channel subfamily C member 6 (TRPC6) is a Ca2+
channel situated on cell membranes, and belongs to the proliferation of PASMCs
caused by hypoxia in mammals. However, its role in hypoxic PASMCs in broilers
remains unclear. Here, we investigated the effects of TRPC6 on the proliferation
and apoptosis of primary chicken PASMCs under hypoxic conditions using an in
vitro model. Primary chicken PASMCs were cultured under normoxic or hypoxic
conditions (3% O2). The hypoxic cells were treated with 10 μM of SKF
96365 or 50 μM of fluofenamic acid (FFA) to inhibit or activate TRPC6,
respectively. Cell viability was detected by CCK-8, intracellular Ca2+
levels, cell cycle and cell apoptosis were assayed by a flow cytometric assay,
the mRNA levels of TRPC6 were measured by digital-droplet PCR (ddPCR), the
protein levels of TRPC6 were tested by immunoblotting, and the mRNA levels of
caspase3 were detected by RT-PCR. Our results revealed that exposing PASMCs to
hypoxic conditions for 48h increased cell viability and intracellular Ca2+
levels. Additionally, hypoxic conditions increased the expression of TRPC6 and
promoted cell cycle progression, but decreased cell apoptosis and caspase 3 mRNA
levels. When the hypoxic PASMCs were treated with SKF 96365, inhibition of TRPC6
and cell proliferation and promotion of apoptosis were observed only in the
first 24h of treatment. Treatment with FFA for 24h had the opposite effects.
These results suggested that TRPC6-mediated Ca2+ entry contributed to
hypoxia-induced PASMCs proliferation and apoptosis resistance, which identified
TRPC6 as a possible key target in vascular remodeling in chicken.
To Cite This Article:
Qiao N, Pan J, Chen H, Kang Z, Pang C, Liu B,
Zeng Q, Mehmood K, Bilal RM, Pasha RH, Qudratullah, Tang Z and Li Y, 2022.
Hypoxia promotes proliferation and inhibits apoptosis of pulmonary arterial
smooth muscle cells via modulating TRPC6. Pak Vet J, 42(1): 9-16.
http://dx.doi.org/10.29261/pakvetj/2021.042