No abstract available.
Adrenergic beta-3 Receptor Agonists/therapeutic use ; Humans ; Muscarinic Antagonists/therapeutic use ; Precision Medicine/methods/*trends ; Urinary Bladder, Overactive/*therapy

BACKGROUNDStimulation of the heart beta 3-adrenoceptor (AR) may result in a negative inotropic effect. Being up-regulated, beta 3-AR plays a more important role in the regulation of cardiac function during heart failure. However, the effect of chronic blocking of beta 3-AR on heart failure has not been fully elucidated. In this study, we used a selective beta 3-AR antagonist SR59230A to treat a well defined heart failure rat model chronically, then evaluated its effect on cardiac function and investigated the mechanism.

METHODSMale Wistar rats were chosen randomly as controls (n = 8). Isoproterenol induced heart failure rats were randomly divided into ISO group (n = 10) and SR group (n = 10). The ISO group received intraperitoneal injection of 1 ml saline twice a day; the SR group received intraperitoneal injection of SR59230A 85 nmol in 1 ml saline twice a day; and the control group received no treatment. The treatment was started 24 hours after the last isoproterenol injection and continued for 7 weeks. Then we measured the following indexes: the ratio of heart weight to body weight (HW/BW) and the ratio of left ventricular weight to body weight (LVW/BW), collagen volume fraction (CVF), left ventricular end diastolic dimension (LVEDd), left ventricular end systolic dimension (LVESd), ejection fraction (EF), fractional shortening (FS) and the ratio of E wave to A wave (E/A), the mRNA and protein expression of beta 3-AR and eNOS, and cGMP level in the heart.

RESULTSThe ratios HW/BW and LVW/BW were significantly increased in the ISO group compared with the control group (P < 0.01), but they were limited in the SR group (P < 0.05 compared with the ISO group). CVF increased in the ISO group and the SR group (P < 0.01), but it was significantly attenuated in the SR group (P < 0.01). LVEDd, LVESd and E/A ratio were significantly increased in the ISO group compared with the control group (P < 0.01), while EF and FS were significantly decreased (P < 0.01). Compared with the ISO group, the SR group showed that LVEDd, LVESd and E/A ratio were significantly decreased (P < 0.01), whereas EF and FS were significantly increased (P < 0.01). beta(3)-AR and eNOS mRNA and protein in the ISO group were significantly increased when compared with the control group (P < 0.01). These increases were all attenuated in the SR group compared with the ISO group (P < 0.01). The level of cGMP in myocardial tissue was significantly increased in the ISO group compared with the control group (P < 0.01), whereas SR59230A treatment normalized this increment (P < 0.01).

CONCLUSIONSChronic blocking of beta 3-AR could ameliorate cardiac function in heart failure rats and its mechanism involves inhibition of the negative inotropic effect and attenuation of cardiac remodeling.

Adrenergic beta-3 Receptor Antagonists ; Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Animals ; Blotting, Western ; Disease Models, Animal ; Echocardiography ; Enzyme-Linked Immunosorbent Assay ; Heart Failure ; drug therapy ; physiopathology ; Male ; Myocardium ; pathology ; Nitric Oxide Synthase Type III ; genetics ; Propanolamines ; pharmacology ; Rats ; Rats, Wistar ; Receptors, Adrenergic, beta-3 ; physiology ; Reverse Transcriptase Polymerase Chain Reaction ; Ventricular Function, Left ; drug effects

After the approval and introduction of mirabegron, tadalafil, and botulinum toxin A for treatment of lower urinary tract symptoms/overactive bladder, focus of interest has been on their place in therapy versus the previous gold standard, antimuscarinics. However, since these agents also have limitations there has been increasing interest in what is coming next - what is in the pipeline? Despite progress in our knowledge of different factors involved in both peripheral and central modulation of lower urinary tract dysfunction, there are few innovations in the pipe-line. Most developments concern modifications of existing principles (antimuscarinics, beta3-receptor agonists, botulinum toxin A). However, there are several new and old targets/drugs of potential interest for further development, such as the purinergic and cannabinoid systems and the different members of the transient receptor potential channel family. However, even if there seems to be good rationale for further development of these principles, further exploration of their involvement in lower urinary tract function/dysfunction is necessary.
Adrenergic beta-3 Receptor Agonists/therapeutic use ; Botulinum Toxins, Type A/therapeutic use ; Drug Therapy, Combination ; Humans ; Molecular Targeted Therapy/methods/trends ; Muscarinic Antagonists/therapeutic use ; Neuromuscular Agents/therapeutic use ; Urinary Bladder, Overactive/*drug therapy

OBJECTIVETo evaluate the effects of Carvedilol on cardiopulmonary bypass (CPB)-induced myocardiocyte apoptosis and its effects on regulation of Fas, FasL expression, caspase-3 activity and oxidative stress in the left ventricle (LV) in this setting.

METHODSTen adult dogs undergoing conventional hypothermic CPB were randomly divided into control and Carvedilol treated groups (n = 5, respectively). Dogs in Carvedilol treated group received a bolus of Carvedilol (1 mg/kg) intravenously and a maintenance dosage of Carvedilol (3 micro g.min(-1).kg(-1)) for 3 hours after the reperfusion of the heart. Dogs in control group received no Carvediolol. LV samples were obtained before, during and 3 hours after CPB. In situ nick end-labeling (TUNEL) technique was used to detect the apoptotic cells. The expressions of Fas and FasL were detected immunohistochemically and quantified by fluorescence activated cell sorting (FACS). The activity of caspase-3 enzyme and malondialdehyde (MDA) level were measured by cleavage of Z-DEVD-AMC substrate and thiobarbituric acid reactive substance (TBARS) method, respectively.

RESULTSBefore and during CPB, all the parameters were not significantly different intra- or between groups (P > 0.05). After CPB, these parameters in both groups were significantly elevated compared with those of before and during CPB (P < 0.028, respectively). However, the number of apoptotic cells in Carvedilol treated group was significantly decreased compared with that of the control group (P < 0.021). The expressions of Fas and FasL were significantly downregulated by Carvedilol (P < 0.001 and 0.003, respectively). The caspase-3 activity and the content of MDA in the Carvedilol treated group was also significantly reduced (P < 0.026 and 0.005, respectively).

CONCLUSIONSCarvedilol significantly reduces CPB-induced cardiomyocyte apoptosis in dog hearts and the reduction of cardiomyocyte apoptosis is associated with downregulation of Fas and FasL expression, inhibition of caspase-3 activity and oxidative stress in LV.

Adrenergic beta-Antagonists ; pharmacology ; Animals ; Apoptosis ; Carbazoles ; pharmacology ; Cardiopulmonary Bypass ; Caspase 3 ; Caspases ; metabolism ; Dogs ; Down-Regulation ; Fas Ligand Protein ; Female ; In Situ Nick-End Labeling ; Male ; Membrane Glycoproteins ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Propanolamines ; pharmacology ; Signal Transduction ; fas Receptor ; metabolism