Table 2. Experimental pharmacological studies addressing RV dysfunction (indirectly, directly).
| Target/mode of action | Model/species | Molecule | Main phenotypic findings | Benefit for RV contractile function | Absence of benefit for RV contractile function | Ref. |
|---|---|---|---|---|---|---|
| Using approved PAH therapeutics | ||||||
| PDE-5, inhibition | PAB, AC-shunt, rat | Sildenafil | PAB: ↑RV systolic function, exercise capacity, RV fibrosis | x | (38) | |
| No effect: RVH, RV diastolic function | ||||||
| No effect in AC-shunt | ||||||
| PDE-5, inhibition | PAB, rat | Sildenafil | ↓RV fibrosis | x | (34) | |
| ↑RV diastolic function | ||||||
| No effect: RV systolic function, exercise capacity | ||||||
| PDE-5, inhibition | PAB, mouse | Sildenafil | ↑RV systolic function | x | (36) | |
| No effect: RVH, RV fibrosis | ||||||
| Prostacyclin, analogue | SuHx, PAB, rat | Iloprost | ↓RV fibrosis | x | (35) | |
| ↑Exercise capacity (SuHx), RV systolic function (SuHx) | ||||||
| No effect: PA remodeling, RV systolic function (PAB) | ||||||
| Soluble guanylate cyclase, activator | PAB, mouse | Riociguat | ↓RV fibrosis | x | (36) | |
| ↑RV systolic function | ||||||
| No effect: RVH | ||||||
| Targeting adrenoceptors | ||||||
| β-adrenoceptor, blockade | MCT, rat | Arotinolol | ↓RVH, RVSP | (39) | ||
| β-adrenoceptor, blockade | MCT, rat | Bisoprolol | ↓RV fibrosis | x | (40) | |
| ↑RV systolic function | ||||||
| β-adrenoceptor, blockade | MCT, SuHx, rat | Carvedilol, metoprolol | ↓RVH | x | (41) | |
| ↑ RV systolic function, exercise capacity (SuHx), survival (MCT) | ||||||
| No effect: RVSP, PA remodeling | ||||||
| β-adrenoceptor, blockade | MCT, rat | Nebivolol | ↓PA remodeling | x | (42) | |
| ↑RV systolic function | ||||||
| β-adrenoceptor, enhancement of signaling | MCT, PAB, rat | Gallein | ↑ RV systolic function (MCT), exercise capacity (PAB) | x | (43) | |
| α1A-adrenoceptor, agonism | Bleomycin, mouse | A61603 | ↓RV fibrosis | x | (44) | |
| ↑RV systolic function | ||||||
| No effect: PA remodeling | ||||||
| α1A-adrenoceptor, agonism | PAB, mouse | A61603 | ↓Liver weight | x | (45) | |
| ↑RV systolic function, exercise capacity | ||||||
| No effect: RVH, RV fibrosis, RV diastolic function | ||||||
| Targeting the renin-angiotensin-aldosterone system | ||||||
| AT1 receptor, antagonism | MCT, rat | Losartan | ↓PVR, PA remodeling | x | (46) | |
| ↑RV diastolic function | ||||||
| No effect: RV contractility | ||||||
| AT1 receptor, antagonism | PAB, rabbit | Losartan | No effect: RVH, RV systolic function | x | (47) | |
| Neprilysin, inhibition; AT1 receptor, antagonism | PAB, rat | Sacubitril/valsartan | ↓RVH | x | (48) | |
| ↑RV systolic and diastolic function | ||||||
| ACE, inhibition | PAB, rabbit | Ramipril | No effect: RVH, RV systolic function | x | (47) | |
| AT1 receptor + mineralocorticoid receptor, antagonism | PAB, rat | Losartan + eplerenone | No effect: RV systolic function, RV remodeling, survival | x | (49) | |
| ACE2 | PAB, mouse | ACE2 | ↓RVH | x | (50) | |
| ↑RV systolic function | ||||||
| No effect: RV fibrosis | ||||||
| ACE2 | MCT, rat | ACE2 | ↓RVH, PA remodeling | x | (51) | |
| ↑RV systolic function | ||||||
| ACE2, activation | MCT, HOX, bleomycin, rat | Diminazene aceturate | ↓RVH, RV fibrosis, PA remodeling | x | (52) | |
| ↑RV systolic function | ||||||
| Mineralocorticoid receptor, antagonism | HOX, mouse, MCT, rat | Spironolactone | HOX: ↓RVSP, RV fibrosis, PA remodeling | (53) | ||
| MCT: ↓RVSP, PA remodeling, PVR | ||||||
| No effect: RV fibrosis, RV remodeling | ||||||
| Mineralocorticoid receptor, antagonism | MCT, rat | Spironolactone | ↓RVSP, PA remodeling, PVR | (54) | ||
| Mineralocorticoid receptor, antagonism | SuHx, rat | Eplerenone | ↓PA remodeling, PVR | (54,55) | ||
| Mineralocorticoid receptor, antagonism | SuHx, rat | Spironolactone | ↓RVH, RVSP, PVR | (55) | ||
| AT1 receptor + mineralocorticoid receptor | PAB rats | Losartan + eplerenone | No effect: RV function, RV remodeling, survival | x | (49) | |
| Mineralocorticoid receptor, antagonism | SuHx, PAB, mouse | Eplerenone | ↓RVH, RVSP, PA remodeling | (56) | ||
| PAB: No effect: RVH, RV fibrosis, RV systolic function | ||||||
| Targeting inflammation and oxidative stress | ||||||
| Nrf2, stimulation of activity and expression | HOX, SuHx, mouse | Dimethyl-fumarate | ↓RVSP, RVH, PA remodeling | (57) | ||
| Nrf2, stimulation of activity and expression | HOX, mouse | Oltipraz | ↓RVH, PA remodeling | (58) | ||
| SOD, SOD mimetic | MCT, rat | EUK 134 | ↓RV fibrosis, RVH | x | (59) | |
| ↑ RV systolic function | ||||||
| NADPH-oxidase, decrease of expression and activity | HOX, mouse | Rosiglitazone | ↓RVSP, PA remodeling | (60) | ||
| Vascular ROS release, reduction; PASMCs proliferation, decrease | HOX, mouse | OA-NO2 | ↓RVSP, RVH, PA remodeling | (61) | ||
| MPO, inhibition | SuHx, rat | AZM198 | ↓RVSP, RVH, PA remodeling | (62) | ||
| NF-κB, inhibition | PAB, rat | E6446, Pyrrolidine dithiocarbamate | ↓ RV fibrosis | x | (63) | |
| ↑ RV systolic function | ||||||
| No effect: RVH | ||||||
| ASK1, inhibition | PAB, mouse; SuHx, MCT, rat | GS-444217 | ↓RV fibrosis, RVH, PA remodeling (in MCT and SuHx) | x | (64) | |
| ↑RV systolic function | ||||||
| p38MAPK, inhibition | PAB, HOX, mouse | PH797804 | ↓RV fibrosis Increased: RV systolic function | x | (65) | |
| TNF-alpha, antagonism | MCT, rat | Etanercept | ↓RVSP, PA remodeling | (66) | ||
| TNF-alpha, antagonism | Endotoxin-induced, pig | Etanercept | ↓RVSP, PVR | (67) | ||
| ↑RV diastolic function | ||||||
| IL-6, IL6R/sIL6R antagonism | MCT, SuHx, rat | ERBF | ↓RVSP, RVH, PA remodeling | x | (68) | |
| ↑RV systolic function | ||||||
| IL-1, receptor antagonism | MCT, HOX, rat | IL-1 receptor antagonist | MCT: ↓RVH, RVSP, PA remodeling | (69) | ||
| HOX: no effect | ||||||
| Targeting energy metabolism | ||||||
| PDK, inhibition | PAB, MCT rat | Dichloroacetate | ↓RVH | x | (70) | |
| ↑RV systolic function | ||||||
| PDK, inhibition | HOX, rat | Dichloroacetate | ↓RVH, PVR, RVSP, PA constriction and remodeling | (71) | ||
| ↑RV CO | ||||||
| PDK, inhibition | MCT, rat | Dichloroacetate | ↓PA remodeling, RVH, mortality | (72) | ||
| PDK, inhibition | RV volume overload, pig | Dichloroacetate | ↓RVH | x | (73) | |
| ↑RV contractile reserve | ||||||
| FAO, partial inhibition | PAB, rat | Trimetazidine, ranolazine | ↓RVH, RV fibrosis | x | (74) | |
| ↑RV systolic function, exercise capacity | ||||||
| FAO, partial inhibition | MCT, HOX rat | Trimetazidine | ↓RVSP, RVH, PA remodeling | (75) | ||
| RV lipid deposition, reduction | BMPR2 R899X, mouse | Metformin | ↓RV lipid accumulation | x | (76) | |
| No effect: RV systolic and diastolic function | ||||||
| RV lipid deposition, reduction | Western diet + PAB, mouse | Metformin | ↓RVSP, RVH | x | (77) | |
| ↑RV diastolic function | ||||||
| PPARγ activation, reduction of RV intramyocardial lipid deposition | SuHx, rat | Pioglitazone | ↓RVSP, RVEDP, RVH, RV fibrosis, PA remodeling | x | (78) | |
| ↑RV systolic function, RV diastolic function | ||||||
| PPARγ, activation | ApoE-ko + HFD, mouse | Rosiglitazone | ↓RVSP, RVH, PA remodeling | x | (79) | |
| PPARγ, activation | HOX, rat | Rosiglitazone | ↓RVSP, RVH, PA remodeling | (80) | ||
| PPARγ, activation | MCT, rat | Pioglitazone | ↓RVSP, RVH, RV fibrosis, PA remodeling | (81) | ||
| ↑Survival | ||||||
| Targeting tyrosine kinases | ||||||
| Tyrosine kinase, inhibition | MCT, rat, HOX, mouse | Imatinib | ↓RVH, RVSP, PA remodeling | (82) | ||
| Targeting extracellular matrix remodeling | ||||||
| Galectin-3, inhibition | PAB, mouse | N-acetyllactosamine | ↓RV fibrosis | x | (83) | |
| No effect: RV systolic function | ||||||
| Targeting HDACs | ||||||
| HDAC class I, II, IV, inhibition | HOX, rat | Valproic acid, suberoylanilide | ↓RVH, RVSP, PA remodeling | (84) | ||
| HDAC class I, inhibition | HOX, rat | MGCD0103 | ↓RVSP, PA remodeling | x | (85) | |
| No effect: RV systolic function | ||||||
| HDAC class I, II, inhibition | PAB, rat | Trichostatin A, valproic acid | ↓RV systolic function | (86) | ||
| ↑RV fibrosis | ||||||
| HDAC class I, inhibition | MCT, rat | Valproic acid | ↓PA remodeling, RVH | (87) | ||
| HDAC class I, II, inhibition | SuHx, rat | Trichostatin A | No effect: PA remodeling, RV systolic function, RVSP, RVH | x | (88) | |
| HDAC class VI, inhibition | SuHx, MCT, rat | Tubastatin A | ↓PA remodeling, RVH, RVSP, PVR | (89) | ||
ACE, angiotensin-converting enzyme; ApoE-ko, apolipoprotein E-knockout; AT1, angiotensin II receptor type 1; HDAC, histone deacetylase; HFD, high fat diet; HOX, hypoxia; MCT, monocrotaline; Nrf2, nuclear factor erythroid 2-related factor 2; PDE-5, phosphodiesterase-5; PA, pulmonary artery; PAB, pulmonary artery banding; PVR, pulmonary vascular resistance; RV, right ventricle; RVH, right ventricular hypertrophy; RVSP, right ventricular systolic pressure; SuHx, Sugen5416/hypoxia.