Comparison of natural estrogens and synthetic derivative on genioglossus function and estrogen receptors expression in rats with chronic intermittent hypoxia

Noradrenergic Activation of Hypoglossal Nucleus Modulates the Central Regulation of Genioglossus in Chronic Intermittent Hypoxic Rats

“…It had been reported that estrogen could partly reverse the contractile properties and fiber type distribution caused by CIH in rats (25). On the contrary, CIH could decrease the expression of estrogen receptor at both the mRNA and protein levels in rats (26). Thus, we only used male rats to exclude the influence of sex hormones on our outcome measures.…”

Sex, stress and sleep apnoea: Decreased susceptibility to upper airway muscle dysfunction following intermittent hypoxia in females

“…Longer-lasting exposures to CIH (35 days compared with 9 days in Skelly et al, 2012a) cause genioglossus dysfunction in female rats Huang & Liu, 2011;Lu et al, 2014;Li & Liu, 2009), but interestingly, CIH-induced upper airway muscle dysfunction is exacerbated in ovariectomized females Huang & Liu, 2011), and partially ameliorated by oestrogen replacement therapy , which is also effective in restoring CIH-induced HIF-1 levels and decreased SERCA activity . Phytoestrogens, particularly genistein, improves upper airway muscle function in ovariectomized females exposed to CIH (Huang & Liu, 2011), associated with muscle upregulation of oestrogen receptor  (Li & Liu, 2009), though the effects may be unrelated to oestrogenic actions (Huang & Liu, 2011).…”

“…When extended for several weeks of exposure, CIH can also increase upper airway muscle fatigue and delay recovery from fatigue (McGuire et al, 2002a,b). CIH increases genioglossus fatigue Huang & Liu, 2011;Ding & Liu, 2011;Wang et al, 2013;Lu et al, 2014;Li & Liu, 2009), which may be HIF-1-dependent Ding & Liu, 2011), and related to mitochondrial dysfunction (Zhang et al, 2010;Huang et al, 2012Huang et al, , 2014. CIH increases endoplasmic reticulum stress and apoptotic signalling , with evidence of aberrant sub-cellular structural remodelling (Huang et al, 2012;Zhang et al, 2010), although only modest cellular oxidative stress has been noted in some models .…”

The secretome of human dental pulp stem cells protects myoblasts from hypoxia‑induced injury via the Wnt/β‑catenin pathway

“…Hypoxia occurs during numerous common phenomena, including embryogenesis, exposure to high-altitude areas, physical exercise and diseases (1,2). Pathological hypoxia can impair skeletal muscle function, a characteristic that it shares with chronic hypoxia-related diseases, such as chronic heart failure (3), chronic obstructive pulmonary disease (4), type 2 diabetes (5) and obstructive sleep apnea syndrome (6,7). Hypoxia leads to continuous muscle contraction, which in turn leads to muscle fatigue and abnormalities in the morphological structure of muscle cells, which inhibits myogenic differentiation (8)(9)(10).…”