Biology subjects

Cogolludo, A.

Publications and source records attributed to Cogolludo, A..

4 recordsLinked to original sources

bioRxiv2023

Vitamin D deficiency induces erectile dysfunction: role of superoxide

Epidemiological studies suggest a relationship between vitamin D deficiency and erectile dysfunction (ED) but its causal relationship and the mechanism involved are unclear. Here we demonstrate that isolated corpora cavernosa (CC) from human donors with low vitamin D levels show reduced NO-dependent erectile function. This ED is also reproduced in vitamin D deficient rats and vitamin D receptor knockout mice in vivo and ex vivo and is associated with penile fibrosis. Vitamin D deficiency also blunts the response of CC to the phosphodiesterase 5 inhibitor sildenafil. CC from deficient rats show increased superoxide and their impaired erectile function is restored by superoxide scavengers. These results suggest that vitamin D deficiency induces ED via increased superoxide production.

pharmacology and toxicology↗

bioRxiv2022

Cigarette smoke induces pulmonary arterial dysfunction through an imbalance in the guanylyl cyclase redox status.

Chronic obstructive pulmonary disease (COPD), whose main risk factor is cigarette smoking (CS), is one of the most common diseases globally. Many COPD patients also develop pulmonary hypertension (PH), a severe complication that leads to premature death. Evidence suggests reactive oxygen species (ROS) involvement in COPD and PH, especially regarding pulmonary artery smooth muscle cells (PASMC) dysfunction. However, the effects of CS on the pulmonary vasculature are not completely understood. Herein we provide evidence on the effects of CS extract (CSE) exposure on PASMC regarding ROS production, antioxidant response and its consequences on vascular tone dysregulation. Our results indicate that CSE exposure promotes mitochondrial fission, mitochondrial membrane depolarization and increased mitochondrial superoxide levels. However, the increase in superoxide did not parallel a counterbalancing antioxidant response in human pulmonary artery (PA) cells. Interestingly, the mitochondrial superoxide chelator mitoTEMPO reduced mitochondrial fission and membrane potential depolarization caused by CSE. As we have previously shown, CSE reduces PA vasoconstriction and vasodilation. In this respect, mitoTEMPO prevented the impaired nitric oxide-mediated vasodilation, while vasoconstriction remained reduced. Finally, we observed a CSE-driven downregulation of the Cyb5R3 enzyme, which prevents soluble guanylyl cyclase oxidation in PASMC. This might explain the CSE-mediated decrease in PA vasodilation. These results provide evidence that there might be a connection between mitochondrial ROS and altered vasodilation responses in PH secondary to COPD, and strongly support the potential of antioxidant strategies specifically targeting mitochondria as a new therapy for these diseases. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

cell biology↗

bioRxiv2019

Direct Effects of Cigarette Smoke in Pulmonary Arterial Cells alter Vascular Tone through Arterial Remodeling and Kv7.4 Channel Dysregulation.

Chronic obstructive pulmonary disease (COPD) is a widespread disease, with no curative therapies nowadays. Exposure to cigarette smoking is considered the chief leading cause of COPD. Current drugs therapies improve patient quality of life, however they do not revert the progression of the disease. Therefore, a deeper study of the cellular and molecular mechanisms that underlie this pathology is required to be able to carry out targeted and effective treatments. Although the effects of cigarette smoke in the progressive deterioration of the airway have been extensively studied in COPD patients, its effects on pulmonary vasculature have been unexplored, due to the classic conception that vascular damage is a consequence of alveolar hypoxia and loss of capillary bed. In this paper, we aimed to study the effects of cigarette smoke extract (CSE) in regulating pulmonary arterial cells phenotypic modulation, in particular the effects in fibroblasts (hPAFib) and smooth muscle cells (hPASMC), and in murine pulmonary arteries. Our results demonstrated that CSE exposure had direct effects on hPAFib and hPASMC, promoting a senescent phenotype that in turn contributed, through the secretion of inflammatory molecules, to increase the proliferative potential of non-exposed cells. CSE also increased total ROS levels in hPAFib and hPASMC, and upregulated NADPH oxidase subunits NOX1 and p22phox. Most importantly, CSE affected cell contractility and dysregulated the expression and activity of voltage-gated K+ channel Kv7.4. This contributed to limit vascular responses impairing vasoconstriction and endothelium-dependent and independent relaxation.

cell biology↗

bioRxiv2018

Mitochondrial Na+ import controls oxidative phosphorylation and hypoxic redox signalling

All metazoans depend on O2 delivery and consumption by the mitochondrial oxidative phosphorylation (OXPHOS) system to produce energy. A decrease in O2 availability (hypoxia) leads to profound metabolic rewiring. In addition, OXPHOS uses O2 to produce reactive oxygen species (ROS) that can drive cell adaptations through redox signalling, but also trigger cell damage1-4, and both phenomena occur in hypoxia4-8. However, the precise mechanism by which acute hypoxia triggers mitochondrial ROS production is still unknown. Ca2+ is one of the best known examples of an ion acting as a second messenger9, yet the role ascribed to Na+ is to serve as a mere mediator of membrane potential and collaborating in ion transport10. Here we show that Na+ acts as a second messenger regulating OXPHOS function and ROS production by modulating fluidity of the inner mitochondrial membrane (IMM). We found that a conformational shift in mitochondrial complex I during acute hypoxia11 drives the acidification of the matrix and solubilization of calcium phosphate precipitates. The concomitant increase in matrix free-Ca2+ activates the mitochondrial Na+/Ca2+ exchanger (NCLX), which imports Na+ into the matrix. Na+ interacts with phospholipids reducing IMM fluidity and mobility of free ubiquinone between complex II and complex III, but not inside supercomplexes. As a consequence, superoxide is produced at complex III, generating a redox signal. Inhibition of mitochondrial Na+ import through NCLX is sufficient to block this pathway, preventing adaptation to hypoxia. These results reveal that Na+ import into the mitochondrial matrix controls OXPHOS function and redox signalling through an unexpected interaction with phospholipids, with profound consequences in cellular metabolism.

biochemistry↗