Carboxyeosin decreases the rate of decay of the [Ca 2+ ] i transient in uterine smooth muscle cells isolated from pregnant rats

Background/Aims: Chronic hypoxia in utero could impair vascular functions in the offspring, underlying mechanisms are unclear. This study investigated functional alteration in large-conductance Ca2+-activated K+ (BK) channels in offspring mesenteric arteries following prenatal hypoxia. Methods: Pregnant rats were exposed to normoxic control (21% O2, Con) or hypoxic (10.5% O2, Hy) conditions from gestational day 5 to 21, their 7-month-old adult male offspring were tested for blood pressure, vascular BK channel functions and expression using patch clamp and wire myograh technique, western blotting, and qRT-PCR. Results: Prenatal hypoxia increased pressor responses and vasoconstrictions to phenylephrine in the offspring. Whole-cell currents density of BK channels and amplitude of spontaneous transient outward currents (STOCs), not the frequency, were significantly reduced in Hy vascular myocytes. The sensitivity of BK channels to voltage, Ca2+, and tamoxifen were reduced in Hy myocytes, whereas the number of channels per patch and the single-channel conductance were unchanged. Prenatal hypoxia impaired NS1102- and tamoxifen-mediated relaxation in mesenteric arteries precontracted with phenylephrine in the presence of Nω-nitro-L-arginine methyl ester. The mRNA and protein expression of BK channel β1, not the α-subunit, was decreased in Hy mesenteric arteries. Conclusions: Impaired BK channel β1-subunits in vascular smooth muscle cells contributed to vascular dysfunction in the offspring exposed to prenatal hypoxia.

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Mesenchymal Stem Cells Attenuate Lipopolysaccharide-Induced Inflammatory Response in Human Uterine Smooth Muscle Cells

American Journal of Perinatology Reports ◽

10.1055/s-0040-1715166 ◽

2020 ◽

Vol 10 (03) ◽

pp. e335-e341

Author(s):

Arunmani Mani ◽

John W. Hotra ◽

Sean C. Blackwell ◽

Laura Goetzl ◽

Jerrie S. Refuerzo

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Smooth Muscle ◽

Preterm Birth ◽

Inflammatory Response ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Uterine Smooth Muscle ◽

Cell Based Therapy ◽

Increased Risk

Abstract Objective The aim of this study was to determine if mesenchymal stem cells (MSCs) would suppress the inflammatory response in human uterine cells in an in vitro lipopolysaccharide (LPS)-based preterm birth (PTB) model. Study Design Cocultures of human uterine smooth muscle cells (HUtSMCs) and MSCs were exposed to 5 μg/mL LPS for 4 hours and further challenged with 1 μg/mL LPS for a subsequent 24 hours. Key elements of the parturition cascade regulated by toll-like receptors (TLRs) through activation of mitogen-activated protein kinases (MAPKs) were quantified in culture supernatant as biomarkers of MSC modulation. Results Coculture with MSCs significantly attenuated TLR-4, p-JNK, and p- extracellular signal-regulated kinase 1/2 (ERK1/2) protein levels compared with HUtSMCs monoculture (p = 0.05). In addition, coculture was associated with significant inhibition of proinflammatory cytokines interleukin (IL)-6 and IL-8 (p = 0.0001) and increased production of anti-inflammatory cytokines IL-10 and transforming growth factor (TGF)-β1 (p = 0.0001). Conclusion MSCs appear to play a role in significantly attenuating LPS-mediated inflammation via alteration of down-stream MAPKs. MSCs may represent a novel, cell-based therapy in women with increased risk of inflammatory-mediated preterm birth.

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