β2-Adrenergic agonists augment air pollution–induced IL-6 release and thrombosis

Acute exposure to particulate matter (PM) air pollution causes thrombotic cardiovascular events, leading to increased mortality rates; however, the link between PM and cardiovascular dysfunction is not completely understood. We have previously shown that the release of IL-6 from alveolar macrophages is required for a prothrombotic state and acceleration of thrombosis following exposure to PM. Here, we determined that PM exposure results in the systemic release of catecholamines, which engage the β₂-adrenergic receptor (β₂AR) on murine alveolar macrophages and augment the release of IL-6. In mice, β₂AR signaling promoted the development of a prothrombotic state that was sufficient to accelerate arterial thrombosis. In primary human alveolar macrophages, administration of a β₂AR agonist augmented IL-6 release, while the addition of a beta blocker inhibited PM-induced IL-6 release. Genetic loss or pharmacologic inhibition of the β₂AR on murine alveolar macrophages attenuated PM-induced IL-6 release and prothrombotic state. Furthermore, exogenous β₂AR agonist therapy further augmented these responses in alveolar macrophages through generation of mitochondrial ROS and subsequent increase of adenylyl cyclase activity. Together, these results link the activation of the sympathetic nervous system by β₂AR signaling with metabolism, lung inflammation, and an enhanced susceptibility to thrombotic cardiovascular events.     

Experiences of Urban African Americans with Cancer Pain

The experience of cancer pain is poorly understood from the perspective of African Americans, who experience higher levels of pain, more pain-related distress, and poorer function than Caucasians. Decreased perceived control over pain may play a greater role for African American patients, affecting pain-related distress and function. The purpose of this study was to add to the understanding of cancer pain and perceived control over pain in African Americans, from the patients’ perspective. This qualitative inquiry was part of a larger mixed-methods study testing an intervention to improve pain, pain-related distress, and functional status through increasing perceived control over pain. Participants were recruited from the waiting room of an urban comprehensive cancer and interviewed in their homes. Interviews with 18 adult cancer patients who self-identified as African American and reported experiencing moderate to severe pain (>4 on a 0–10 scale) within the past two weeks were included. Qualitative interviews were audiotaped, transcribed, and analyzed using a constant comparative method. Two major themes emerged from this qualitative inquiry: struggles of the chronic pain experience and benefits of perceived control over pain. Each theme contained several categories. The study unveiled the participants account of both struggles of the chronic pain experience and barriers of perceived control that can be assessed for and targeted in nursing intervention. Benefits to having perceived control over pain were also illustrated in the participants’ narratives.