The addition of a weekly supervised exercise session to our current prehabilitation program did not further enhance postoperative walking capacity when compared to standard REHAB care. Sedentary patients, however, seemed more likely to benefit from PREHAB+. An association was found between energy spent in physical activity and 6MWD. This information is important to consider when designing cost-effective prehabilitation programs.

Abstract-The reactivity of the vascular wall to endothelin-1 (ET-1) is influenced by cholesterol, which is of possible importance for the progression of atherosclerosis. To elucidate signaling steps affected, the cholesterol acceptor methyl-␤-cyclodextrin (m␤cd, 10 mmol/L) was used to manipulate membrane cholesterol and disrupt caveolae in intact rat arteries. In endothelium-denuded caudal artery, contractile responsiveness to 10 nmol/L ET-1 (mediated by the ET A receptor) was reduced by m␤cd and increased by cholesterol. Neither ligand binding nor colocalization of ET A and caveolin-1 was affected by m␤cd. Ca 2ϩ inflow via store-operated channels after depletion of intracellular Ca 2ϩ stores was reduced in m␤cd-treated caudal arteries, as shown by Mn 2ϩ quench rate and intracellular [Ca 2ϩ ] response. Expression of TRPC1, 3, and 6 was detected by reverse transcriptase-polymerase chain reaction, and colocalization of TRPC1 with caveolin-1 was reduced by m␤cd, as seen by immunofluorescence. Part of the contractile response to ET-1 was inhibited by Ni 2ϩ (0.5 mmol/L) and by a TRPC1 blocking antibody. In the basilar artery, exhibiting less store-operated channel activity than the caudal artery, ET-1-induced contractions were insensitive to the TRPC1 blocking antibody and to m␤cd. Increased store-operated channel activity in basilar arteries after organ culture correlated with increased sensitivity of ET-1 contraction to m␤cd. These results suggest that cholesterol influences vascular reactivity to ET-1 by affecting the caveolar localization of TRPC1. Key Words: arterial smooth muscle Ⅲ methyl-␤-cyclodextrin Ⅲ caveolae Ⅲ endothelin Ⅲ store-operated Ca 2ϩ channels H ypercholesterolemia increases reactivity to endothelin-1 (ET-1) in experimental animals and humans. [1][2][3][4] This has been pointed out as one possible factor in the progression of atherosclerosis. [5][6][7] The mechanism of action has not been elucidated, although both endothelial dysfunction and altered smooth muscle reactivity have been proposed. 5 Lipoprotein particles may directly influence endothelial membrane-associated endothelial NO synthase activity by interfering with cholesterol-rich domains referred to as caveolae. 8 Although these effects modulate the endothelial influence on vascular tone, less is known regarding direct effects of cholesterol on vascular smooth muscle functions.Caveolae are 50-to 100-nm membrane invaginations that integrate many cellular receptor functions. 9 For instance, ET A receptors expressed in COS cells colocalize with the caveolae-associated protein caveolin. 10,11 The caveolar structure is disrupted after depletion of cholesterol with cyclodextrins, 12 and this correlates with a decreased contractility to ET-1, but not to depolarization or ␣ 1 -receptor stimulation, in endothelium-denuded rat caudal arteries. 13 Cholesterol might thus modulate the strength of caveolae-associated signaling, providing a basis for altered contractility in response to ET-1.Activation of the ET A receptor stimulates Ca 2ϩ inflow ov...

Occlusive vascular disease is a widespread abnormality leading to lethal or debilitating outcomes such as myocardial infarction and stroke. It is part of atherosclerosis and is evoked by clinical procedures including angioplasty and grafting of saphenous vein in bypass surgery. A causative factor is the switch in smooth muscle cells to an invasive and proliferative mode, leading to neointimal hyperplasia. Here we reveal the importance to this process of TRPC1, a homolog of Drosophila transient receptor potential. Using 2 different in vivo models of vascular injury in rodents we show hyperplasic smooth muscle cells have upregulated TRPC1 associated with enhanced calcium entry and cell cycle activity. Neointimal smooth muscle cells after balloon angioplasty of pig coronary artery also express TRPC1. Furthermore, human vein samples obtained during coronary artery bypass graft surgery commonly exhibit an intimal structure containing smooth muscle cells that expressed more TRPC1 than the medial layer cells. Veins were organ cultured to allow growth of neointimal smooth muscle cells over a 2-week period. To explore the functional relevance of TRPC1, we used a specific E3-targeted antibody to TRPC1 and chemical blocker 2-aminoethoxydiphenyl borate. Both agents significantly reduced neointimal growth in human vein, as well as calcium entry and proliferation of smooth muscle cells in culture. The data suggest upregulated TRPC1 is a general feature of smooth muscle cells in occlusive vascular disease and that TRPC1 inhibitors have potential as protective agents against human vascular failure.

. Contractility of rat cerebral arteries in organ culture is preserved for several days, whereas SOCE is increased. In correlation with this increase is that nifedipine-insensitive whole cell current, activated by depletion of intracellular Ca 2ϩ stores, was increased by 50% in cells isolated from arteries cultured for 3 days. TRPC1 and TRPC6 mRNA were more than fivefold increased in cells isolated after organ culture, whereas TRPC3 was decreased. Immunofluorescent staining and/or Western blotting of arteries and isolated cells showed upregulation of TRPC1 and TRPC6 proteins during organ culture. In intact arteries, TRPC4 expression correlated with the amount of endothelium present. Ca 2ϩ addition after store depletion caused a contraction in cultured, but not in freshly dissected, arteries. A polyclonal TRPC1 antibody directed against an extracellular epitope inhibited this contraction by ϳ50%. To investigate the basis of the TRPC upregulation and assess its possible clinical significance, segments of human internal mammary artery were organ cultured for 24 h and then exposed to balloon dilatation in vitro, followed by further culturing for up to 48 h. After dilatation, TRPC1 and TRPC6 mRNA were progressively increased compared with undilated control segments. The results of this study indicate that vascular injury enhances plasticity in TRPC expression, that TRPC expression correlates with cellular Ca 2ϩ handling, and that TRPC1 is a subunit of upregulated store-operated Ca 2ϩ channels.

These findings highlight the need to make prehabilitation programs more patient-centered. This is critical when designing more effective therapeutic strategies tailored to meet patients' specific needs while overcoming program non-adherence.

These findings highlight the positive effects of a trimodal prehabilitation program on patients' physical activity levels and functional walking capacity and demonstrate that modifying exercise behaviors and improving physical function within the 4-week preoperative period are an achievable goal.

Recent evidence implicates the volume-regulated anion current (VRAC) and other anion currents in control or modulation of cell cycle progression; however, the precise involvement of anion channels in this process is unclear. Here, Cl- currents in Ehrlich Lettre Ascites (ELA) cells were monitored during cell cycle progression, under three conditions: (i) after osmotic swelling (i.e., VRAC), (ii) after an increase in the free intracellular Ca2+ concentration (i.e., the Ca2+-activated Cl- current, CaCC), and (iii) under steady-state isotonic conditions. The maximal swelling-activated VRAC current decreased in G1 and increased in early S phase, compared to that in G0. The isotonic steady-state current, which seems to be predominantly VRAC, also decreased in G1, and increased again in early S phase, to a level similar to that in G0. In contrast, the maximal CaCC current (500 nM free Ca2+ in the pipette), was unaltered from G0 to G1, but decreased in early S phase. A novel high-affinity anion channel inhibitor, the acidic di-aryl-urea NS3728, which inhibited both VRAC and CaCC, attenuated ELA cell growth, suggesting a possible mechanistic link between cell cycle progression and cell cycle-dependent changes in the capacity for conductive Cl- transport. It is suggested that in ELA cells, entrance into the S phase requires an increase in VRAC activity and/or an increased potential for regulatory volume decrease (RVD), and at the same time a decrease in CaCC magnitude.

Mitochondrial dysfunction plays a central role in ischaemia-reperfusion (IR) injury. Pre-ischaemic administration of aminooxyacetate (AOA), an inhibitor of the malate-aspartate shuttle (MAS), provides cardioprotection against IR injury, although the underlying mechanism remains unknown. We hypothesized that a transient inhibition of the MAS during ischaemia and early reperfusion could preserve mitochondrial function at later phase of reperfusion in the IR-injured heart to the same extent as ischaemic preconditioning (IPC), which is a well-validated cardioprotective strategy against IR injury. In the present study, we show that pre-ischaemic administration of AOA preserved mitochondrial complex I-linked state 3 respiration and fatty acid oxidation during late reperfusion in IR-injured isolated rat hearts. AOA treatment also attenuated the excessive emission of mitochondrial reactive oxygen species during state 3 with complex I-linked substrates during late reperfusion, which was consistent with reduced oxidative damage in the IR-injured heart. As a result, AOA treatment reduced infarct size after reperfusion. These protective effects of MAS inhibition on the mitochondria were similar to those of IPC. Intriguingly, the protection of mitochondrial function by AOA treatment appears to be different from that of IPC because AOA treatment, but not IPC, downregulated myocardial tricarboxilic acid (TCA)-cycle intermediates at the onset of reperfusion. MAS inhibition thus preserved mitochondrial respiratory capacity and decreased mitochondrial oxidative stress during late reperfusion in the IR-injured heart, at least in part, via metabolic regulation of TCA cycle intermediates in the mitochondria at the onset of reperfusion.