Miranda E. Good

Bio: Miranda E. Good is an academic researcher from University of Virginia. The author has contributed to research in topics: Pannexin & Vasodilation. The author has an hindex of 14, co-authored 30 publications receiving 498 citations. Previous affiliations of Miranda E. Good include Tufts Medical Center & University of Arizona.

Vascular Smooth Muscle Remodeling in Conductive and Resistance Arteries in Hypertension.

Abstract: Cardiovascular disease is a leading cause of death worldwide and accounts for >173 million deaths per year, with an estimated increase in incidence to 236 million by 2030 1 Cardiovascular death represents 31% of all global deaths 2 -with stroke, heart attack, and ruptured aneurysms predominantly contributing to these high mortality rates A key risk factor for cardiovascular disease is hypertension Although treatment or reduction in hypertension can prevent the onset of cardiovascular events, existing therapies are only partially effective A key pathological hallmark of hypertension is increased peripheral vascular resistance because of structural and functional changes in large (conductive) and small (resistance) arteries In this review, we discuss the clinical implications of vascular remodeling, compare the differences between vascular smooth muscle cell remodeling in conductive and resistance arteries, discuss the genetic factors associated with vascular smooth muscle cell function in hypertensive patients, and provide a prospective assessment of current and future research and pharmacological targets for the treatment of hypertension

Pannexin-1 channels on endothelial cells mediate vascular inflammation during lung ischemia-reperfusion injury.

Abstract: Ischemia-reperfusion (I/R) injury (IRI), which involves inflammation, vascular permeability, and edema, remains a major challenge after lung transplantation. Pannexin-1 (Panx1) channels modulate ce...

Pannexin 1 Channels as an Unexpected New Target of the Anti-Hypertensive Drug Spironolactone.

Abstract: Rationale: Resistant hypertension is a major health concern with unknown etiology. Spironolactone is an effective anti-hypertensive drug, especially for patients with resistant hypertension, and is considered by the World Health Organization (WHO) as an "essential" medication. Although spironolactone can act at the mineralocorticoid receptor (NR3C2), there is increasing evidence of mineralocorticoid receptor (MR)-independent effects of spironolactone. Objective: Here, we detail the unexpected discovery that pannexin 1 (Panx1) channels could be a relevant in vivo target of spironolactone. Methods and Results: First, we identified spironolactone as a potent inhibitor of Panx1 in an unbiased small molecule screen, which was confirmed by electrophysiological analysis. Next, spironolactone inhibited α-adrenergic vasoconstriction in arterioles from mice and hypertensive humans, an effect dependent upon smooth muscle Panx1, but independent of the mineralocorticoid receptor NR3C2. Lastly, spironolactone acutely lowered blood pressure, which was dependent on smooth muscle cell expression of Panx1 and independent of NR3C2. This effect, however, was restricted to steroidal MR antagonists as a non-steroidal MR antagonist failed to reduced blood pressure. Conclusions: These data suggest new therapeutic modalities for resistant hypertension based on Panx1 inhibition.

Red Blood Cell and Endothelial eNOS Independently Regulate Circulating Nitric Oxide Metabolites and Blood Pressure.

Abstract: Background: Current paradigms suggest that nitric oxide (NO) produced by endothelial cells (ECs) via endothelial nitric oxide synthase (eNOS) in the vessel wall is the primary regulator of blood fl...

Pannexin channel and connexin hemichannel expression in vascular function and inflammation.

Abstract: Control of blood flow distribution and tissue homeostasis depend on the tight regulation of and coordination between the microvascular network and circulating blood cells. Channels formed by connexins or pannexins that connect the intra- and extracellular compartments allow the release of paracrine signals, such as ATP and prostaglandins, and thus play a central role in achieving fine regulation and coordination of vascular function. This review focuses on vascular connexin hemichannels and pannexin channels. We review their expression pattern within the arterial and venous system with a special emphasis on how post-translational modifications by phosphorylation and S-nitrosylation of these channels modulate their function and contribute to vascular homeostasis. Furthermore, we highlight the contribution of these channels in smooth muscle cells and endothelial cells in the regulation of vasomotor tone as well as how these channels in endothelial cells regulate inflammatory responses such as during ischemic and hypoxic conditions. In addition, this review will touch on recent evidence implicating a role for these proteins in regulating red blood cell and platelet function.

Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study

Abstract: Summary Background Since December, 2019, Wuhan, China, has experienced an outbreak of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Epidemiological and clinical characteristics of patients with COVID-19 have been reported but risk factors for mortality and a detailed clinical course of illness, including viral shedding, have not been well described. Methods In this retrospective, multicentre cohort study, we included all adult inpatients (≥18 years old) with laboratory-confirmed COVID-19 from Jinyintan Hospital and Wuhan Pulmonary Hospital (Wuhan, China) who had been discharged or had died by Jan 31, 2020. Demographic, clinical, treatment, and laboratory data, including serial samples for viral RNA detection, were extracted from electronic medical records and compared between survivors and non-survivors. We used univariable and multivariable logistic regression methods to explore the risk factors associated with in-hospital death. Findings 191 patients (135 from Jinyintan Hospital and 56 from Wuhan Pulmonary Hospital) were included in this study, of whom 137 were discharged and 54 died in hospital. 91 (48%) patients had a comorbidity, with hypertension being the most common (58 [30%] patients), followed by diabetes (36 [19%] patients) and coronary heart disease (15 [8%] patients). Multivariable regression showed increasing odds of in-hospital death associated with older age (odds ratio 1·10, 95% CI 1·03–1·17, per year increase; p=0·0043), higher Sequential Organ Failure Assessment (SOFA) score (5·65, 2·61–12·23; p Interpretation The potential risk factors of older age, high SOFA score, and d-dimer greater than 1 μg/mL could help clinicians to identify patients with poor prognosis at an early stage. Prolonged viral shedding provides the rationale for a strategy of isolation of infected patients and optimal antiviral interventions in the future. Funding Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences; National Science Grant for Distinguished Young Scholars; National Key Research and Development Program of China; The Beijing Science and Technology Project; and Major Projects of National Science and Technology on New Drug Creation and Development.

Extracellular Cysteine in Connexins: Role as Redox Sensors.

Abstract: Connexin-based channels comprise hemichannels and gap junction channels. The opening of hemichannels allow for the flux of ions and molecules from the extracellular space into the cell and vice versa. Similarly, the opening of gap junction channels permits the diffusional exchange of ions and molecules between the cytoplasm and contacting cells. The controlled opening of hemichannels has been associated with several physiological cellular processes; thereby unregulated hemichannel activity may induce loss of cellular homeostasis and cell death. Hemichannel activity can be regulated through several mechanisms, such as phosphorylation, divalent cations and changes in membrane potential. Additionally, it was recently postulated that redox molecules could modify hemichannels properties in vitro. However, the molecular mechanism by which redox molecules interact with hemichannels is poorly understood. In this work, we discuss the current knowledge on connexin redox regulation and we propose the hypothesis that extracellular cysteine could be important for sensing changes in redox potential. Future studies on this topic will offer new insight into hemichannel function, thereby expanding the understanding of the contribution of hemichannels to disease progression.

Endothelial cation channel PIEZO1 controls blood pressure by mediating flow-induced ATP release

Abstract: Arterial blood pressure is controlled by vasodilatory factors such as nitric oxide (NO) that are released from the endothelium under the influence of fluid shear stress exerted by flowing blood Flow-induced endothelial release of ATP and subsequent activation of Gq/G11-coupled purinergic P2Y2 receptors have been shown to mediate fluid shear stress-induced stimulation of NO formation However, the mechanism by which fluid shear stress initiates these processes is unclear Here, we have shown that the endothelial mechanosensitive cation channel PIEZO1 is required for flow-induced ATP release and subsequent P2Y2/Gq/G11-mediated activation of downstream signaling that results in phosphorylation and activation of AKT and endothelial NOS We also demonstrated that PIEZO1-dependent ATP release is mediated in part by pannexin channels The PIEZO1 activator Yoda1 mimicked the effect of fluid shear stress on endothelial cells and induced vasorelaxation in a PIEZO1-dependent manner Furthermore, mice with induced endothelium-specific PIEZO1 deficiency lost the ability to induce NO formation and vasodilation in response to flow and consequently developed hypertension Together, our data demonstrate that PIEZO1 is required for the regulation of NO formation, vascular tone, and blood pressure

The clearance of dead cells by efferocytosis.

Abstract: Multiple modes of cell death have been identified, each with a unique function and each induced in a setting-dependent manner. As billions of cells die during mammalian embryogenesis and daily in adult organisms, clearing dead cells and associated cellular debris is important in physiology. In this Review, we present an overview of the phagocytosis of dead and dying cells, a process known as efferocytosis. Efferocytosis is performed by macrophages and to a lesser extent by other 'professional' phagocytes (such as monocytes and dendritic cells) and 'non-professional' phagocytes, such as epithelial cells. Recent discoveries have shed light on this process and how it functions to maintain tissue homeostasis, tissue repair and organismal health. Here, we outline the mechanisms of efferocytosis, from the recognition of dying cells through to phagocytic engulfment and homeostatic resolution, and highlight the pathophysiological consequences that can arise when this process is abrogated.