Objective: To explore the protective effects of dexmedetomidine (Dex) against high glucose-induced epithelial-mesenchymal transition in HK-2 cells and relevant mechanisms. Methods: HK-2 cells were exposed to either glucose or glucose+Dex for 6 h. The production of ROS, morphology of HK-2 cells, and cell cycle were detected. Moreover, the expression of AKT, p-AKT, ERK, p-ERK, PI3K, E-Cadherin, Claudin-1, and α-SMA were determined and compared between HK-2 cells exposed to glucose and those exposed to both glucose and Dex with or without PI3K/AKT pathway inhibitor LY294002 and ERK pathway inhibitor U0126. Results: Compared with HK-2 cells exposed to high level of glucose, the HK-2 cells exposed to both high level of glucose and Dex showed: (1) lower level of ROS production; (2) cell morphology was complete; (3) more cells in G1 phase; (4) lower expression of p-AKT, p-ERK and α-SMA, higher expression of E-Cadherin and Claudin-1. PI3K/AKT inhibitor LY294002 and ERK inhibitor U0126 decreased the expression of p-AKT, p-ERK and α-SMA, and increased the expression of E-Cadherin and Claudin-1. Conclusion Dex can attenuate high glucose-induced HK-2 epithelial-mesenchymal transition by inhibiting AKT and ERK.
Adrenergic alpha-2 Receptor Agonists ; pharmacology ; Cell Line ; Dexmedetomidine ; pharmacology ; Epithelial-Mesenchymal Transition ; drug effects ; Glucose ; metabolism ; Humans ; MAP Kinase Signaling System ; drug effects ; Proto-Oncogene Proteins c-akt ; antagonists & inhibitors ; Signal Transduction ; drug effects

BACKGROUND/AIMS: The development of therapeutic strategies for the treatment of cirrhosis has become an important focus for basic and clinical researchers. Adrenergic receptor antagonists have been evaluated as antifibrotic drugs in rodent models of carbon tetrachloride (CCl4)-induced cirrhosis. The aim of the present study was to evaluate the effects of carvedilol and doxazosin on fibrosis/cirrhosis in a hamster animal model. METHODS: Cirrhotic-induced hamsters were treated by daily administration of carvedilol and doxazosin for 6 weeks. Hepatic function and histological evaluation were conducted by measuring biochemical markers, including total bilirubin, aspartate aminotransferase, alanine aminotransferase and albumin, and liver tissue slices. Additionally, transforming growth factor beta (TGF-beta) immunohistochemistry was analyzed. RESULTS: Biochemical markers revealed that hepatic function was restored after treatment with doxazosin and carvedilol. Histological evaluation showed a decrease in collagen type I deposits and TGF-beta-secreting cells. CONCLUSIONS: Taken together, these results suggest that the decrease in collagen type I following treatment with doxazosin or carvedilol is achieved by decreasing the profibrotic activities of TGF-beta via the blockage of alpha1- and beta-adrenergic receptor. Consequently, a diminution of fibrotic tissue in the CCl4-induced model of cirrhosis is achieved.
Adrenergic alpha-1 Receptor Antagonists/*pharmacology ; Alanine Transaminase/blood ; Animals ; Aspartate Aminotransferases/blood ; Bilirubin/blood ; Carbazoles/*pharmacology ; Carbon Tetrachloride ; Collagen Type I/drug effects/metabolism ; Cricetinae ; Doxazosin/*pharmacology ; Liver/metabolism/pathology ; Liver Cirrhosis/blood/chemically induced/*drug therapy ; Liver Function Tests ; Propanolamines/*pharmacology ; Serum Albumin/analysis ; Transforming Growth Factor beta/blood/*drug effects

OBJECTIVEPostural tachycardia syndrome (POTS) is one of the major causes of orthostatic intolerance in children. We systematically reviewed the pathogenesis and the progress of individualized treatment for POTS in children.

DATA SOURCESThe data analyzed in this review are mainly from articles included in PubMed and EMBASE.

STUDY SELECTIONThe original articles and critical reviews about POTS were selected for this review.

RESULTSStudies have shown that POTS might be related to several factors including hypovolemia, high catecholamine status, abnormal local vascular tension, and decreased skeletal muscle pump activity. In addition to exercise training, the first-line treatments mainly include oral rehydration salts, beta-adrenoreceptor blockers, and alpha-adrenoreceptor agonists. However, reports about the effectiveness of various treatments are diverse. By analyzing the patient's physiological indexes and biomarkers before the treatment, the efficacy of medication could be well predicted.

CONCLUSIONSThe pathogenesis of POTS is multifactorial, including hypovolemia, abnormal catecholamine state, and vascular dysfunction. Biomarker-directed individualized treatment is an important strategy for the management of POTS children.

Adrenergic alpha-Agonists ; therapeutic use ; Adrenergic beta-Antagonists ; therapeutic use ; Catecholamines ; metabolism ; Humans ; Postural Orthostatic Tachycardia Syndrome ; drug therapy ; metabolism ; pathology ; therapy

β3-adrenoceptor (β3-AR) has been shown to promote myocardial apoptosis. However, the exact physiological role and importance of this receptor in the human myocardium, and its underlying mode of action, have not been fully elucidated. The present study aimed to determine the effects of β3-AR on the promotion of myocardial apoptosis and on norepinephrine (NE) injury. We analyzed NE-induced cardiomyocyte (CM) apoptosis by using a TUNEL and an annexin V/propidium iodide apoptosis assay. Furthermore, we investigated the NE-induced expression of the apoptosis marker genes Akt and p38MAPK, their phosphorylated counterparts p-Akt and p-p38MAPK, caspase-3, Bcl-2, and Bax. In addition, we determined the effect of a 48-h treatment with a β3-AR agonist and antagonist on expression of these marker genes. β3-AR overexpression was found to increase CM apoptosis, accompanied by an increased expression of caspase-3, bax/bcl-2, and p-p38MAPK. In contrast, the β3-blocker reduced apoptosis of CMs and the associated elevated Akt expression. We identified a novel and potent anti-apoptosis mechanism via the PI3K/Akt pathway and a pro-apoptosis pathway mediated by p38MAPK.
Adrenergic Agonists ; pharmacology ; Adrenergic Antagonists ; pharmacology ; Animals ; Apoptosis ; Cells, Cultured ; Myocytes, Cardiac ; drug effects ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Adrenergic, beta-3 ; genetics ; metabolism ; Signal Transduction ; p38 Mitogen-Activated Protein Kinases ; metabolism

BACKGROUNDPrevious studies have suggested that β1-receptor blockers benefit septic shock patients. This study aimed to determine whether β1-receptor blockers benefit tissue perfusion in sepsis and to identify parameters to reduce the risk of this drug in sepsis.

METHODSConsecutive septic shock patients were recruited from the Intensive Care Unit of Peking Union Medical College Hospital within 48 h of diagnosis. All patients were hemodynamically stable and satisfactorily sedated with a heart rate (HR) ≥100 beats/min. Esmolol therapy achieved the target HR of 10-15% lower than the baseline HR. Clinical and physiological data of patients were collected prospectively within 1 h prior to esmolol therapy and 2 h after achieving the targeted HR.

RESULTSSixty-three patients were recruited. After esmolol therapy, blood pressure was unaltered, whereas stroke volume (SV) was increased compared with before esmolol therapy (43.6 ± 22.7 vs. 49.9 ± 23.7 ml, t = -2.3, P = 0.047). Tissue perfusion, including lactate levels (1.4 ± 0.8 vs. 1.1 ± 0.6 mmol/L, t = 2.6, P = 0.015) and the central venous-to-arterial carbon dioxide difference (5.6 ± 3.3 vs. 4.3 ± 2.2 mmHg, t = 2.6 P = 0.016), was also significantly decreased after esmolol therapy. For patients with increased SV (n = 42), cardiac efficiency improved, and esmolol therapy had a lower risk for a decrease in cardiac output (CO). Therefore, pretreatment cardiac systolic and diastolic parameters with (n = 42)/without (n = 21) an increase in SV were compared. Mitral lateral annular plane systolic excursion (MAPSElat) in patients with increased SV was significantly higher than that in those without increased SV (1.3 ± 0.3 vs. 1.1 ± 0.2 cm, t = 2.4, P = 0.034).

CONCLUSIONSSV of septic shock patients is increased following esmolol therapy. Although CO is also decreased with HR, tissue perfusion is not worse. MAPSElat can be used to predict an increase in SV before esmolol use.

TRIAL REGISTRATIONClinicalTrials.gov, NCT01920776; https://clinicaltrials.gov/ct2/show/NCT01920776?term=NCT01920776&rank=1.

Adrenergic beta-1 Receptor Antagonists ; therapeutic use ; Adult ; Aged ; Cardiac Output ; drug effects ; Echocardiography ; Female ; Heart Rate ; drug effects ; Hemodynamics ; drug effects ; Humans ; Male ; Middle Aged ; Myocardium ; metabolism ; Propanolamines ; therapeutic use ; Shock, Septic ; drug therapy ; Stroke Volume ; drug effects

OBJECTIVE: To evaluate whether dexmedetomidine hydrochloride, an α(2)-adrenergic receptor agonist, can prevent H(2)O(2)-induced oxidative stress and inflammatory response in Kupffer cells.
 METHODS: H(2)O(2)-induced oxidative damage model of Kupffer cell was established. Kupffer cells were pre-conditioned by dexmedetomidine hydrochloride or Yohimbine for 24 h. MTT colorimetry was used to demonstrate the survival rate of Kupffer cells. The levels of lactate dehydrogenase (LDH), malonaldehyde (MDA) and TNF-α in the culture medium were assessed by corresponding kits.
 RESULTS: Dexmedetomidine hydrochloride protected Kupffer cells from H(2)O(2)-induced oxidative damage, showing an increase in the cell survival rate while a decrease in LDH, MDA and TNF-α release in the culture supernatant. Yohimbine, an α(2)-adrenergic receptor antagonist, completely neutralized the protective effect of Dexmedetomidine hydrochloride on Kupffer cells. Yohimbine itself had no effect on H(2)O(2)-induced oxidative damage and inflammatory response.
 CONCLUSION Dexmedetomidine hydrochloride can prevent H(2)O(2)-induced oxidative stress and inflammatory response in Kupffer cells through activation of α(2)-adrenergic receptors.
Adrenergic alpha-2 Receptor Antagonists ; pharmacology ; Cell Survival ; Cells, Cultured ; Dexmedetomidine ; pharmacology ; Humans ; Hydrogen Peroxide ; pharmacology ; Kupffer Cells ; cytology ; drug effects ; L-Lactate Dehydrogenase ; metabolism ; Malondialdehyde ; metabolism ; Oxidative Stress ; drug effects ; Receptors, Adrenergic, alpha-2 ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism ; Yohimbine ; pharmacology

OBJECTIVE: In this study, there was an investigation as to whether there is a functional difference in essential tremor (ET), according to responses to beta-blockers, by evaluating regional changes in cerebral glucose metabolism. MATERIALS AND METHODS: Seventeen male patients with ET were recruited and categorized into two groups: 8 that responded to medical therapy (group A); and 9 that did not respond to medical therapy (group B). Eleven age-sex matched healthy control male subjects were also included in this study. All subjects underwent F-18 fluorodeoxyglucose (FDG)-PET, and evaluated for their severity of tremor symptoms, which were measured as a score on the Fahn-Tolosa-Marin tremor rating scale (FTM). The FDG-PET images were analyzed using a statistical parametric mapping program. RESULTS: The mean FTM score 6 months after the initiation of propranolol therapy was significantly lower in group A (18.13 > 8.13), compared with group B (14.67 = 14.67). The glucose metabolism in group A in the left basal ganglia was seen to be decreased, compared with group B. The ET showed a more significantly decreased glucose metabolism in both the fronto-temporo-occipital lobes, precuneus of right parietal lobe, and both cerebellums compared with the healthy controls. CONCLUSION: Essential tremor is caused by electrophysiological disturbances within the cortical-cerebellar networks and degenerative process of the cerebellum. Furthermore, ET may have different pathophysiologies in terms of the origin of disease according to the response to first-line therapy.
Adrenergic beta-Antagonists/*pharmacology/therapeutic use ; Aged ; Brain/*drug effects/metabolism/radiography ; Brain Mapping ; Essential Tremor/*diagnosis/drug therapy/radiography ; Fluorodeoxyglucose F18/*chemistry ; Glucose/*metabolism ; Humans ; Male ; Middle Aged ; *Positron-Emission Tomography ; Propranolol/pharmacology/therapeutic use ; Radiopharmaceuticals/*chemistry

OBJECTIVECrassostrea gigas oyster extract has been reported to have antioxidant, antihypertensive and lipid-lowering properties that may be useful for treating cardiovascular diseases. This study aimed to evaluate the effect of C. gigas oyster extract on cardiovascular function in tissues from healthy rats.

METHODSSingle-cell microelectrode and isolated thoracic aortic organ bath studies were performed on tissues from 8-week-old healthy Wistar rats, using varying concentrations of C. gigas oyster extract. To elucidate a mechanism of action for the oyster's vasoactive properties, concentration response curves were carried out in the presence of a calcium channel inhibitior (verapamil), a nitric oxide synthase inhibitor (N(G)-nitro-L-arginine methyl ester), a potassium channel inhibitor (4-aminopyridine), in addition to the α-adrenoceptor inhibitor prazosin.

RESULTSOyster solution at 7 500 mg/mL inhibited noradrenaline-induced contraction in isolated aortic rings. Cardiac electrophysiology results showed that neither concentration of oyster solution was able to significantly reduce action potential duration at all phases of repolarisation in left ventricular papillary muscles from healthy animals.

CONCLUSIONWhen administered to healthy vascular tissue, C. gigas oyster extract inhibits contraction induced by noradrenaline. This effect is likely to be mediated through α-adrenoceptor inhibition, and to a lesser extent, calcium modulating activity.

Action Potentials ; drug effects ; Adrenergic alpha-Antagonists ; pharmacology ; Animals ; Aorta, Thoracic ; drug effects ; physiology ; Calcium ; metabolism ; Crassostrea ; Heart ; drug effects ; physiology ; Male ; Norepinephrine ; antagonists & inhibitors ; pharmacology ; Rats ; Rats, Wistar ; Vasoconstriction ; drug effects

Adrenergic receptors are members of the G-protein coupled receptor superfamily. Recent studies revealed that these adrenergic receptors are playing an important role in the growth and metastasis of prostate cancer cells. The expression of adrenergic receptors rises significantly in prostate cancer cells and tissues. Agonists of these receptors promote the growth and mobility of prostate cancer cells, while antagonists may suppress their proliferation, trigger their apoptosis, and inhibit their metastasis. Clinically, receptor antagonists can significantly reduce the risk of prostate cancer and improve its prognosis after androgen depravation therapy. This article presents an overview on the roles of adrenergic receptors in prostate cancer.
Adrenergic Agonists ; pharmacology ; Adrenergic Antagonists ; pharmacology ; Apoptosis ; Humans ; Male ; Prostatic Neoplasms ; metabolism ; pathology ; Receptors, Adrenergic ; drug effects ; physiology

OBJECTIVETo observe the effects of beta3-adrenergic receptor(beta3-AR) antagonist on myocardial uncoupling protein 2 (UCP2) expression and energy metabolism in chronic heart failure rats.

METHODSSeven weight-matched normal adult rats (control group), 18 isoproterenol (ISO) induced heat failure (HR) rats (ISO group) and 21 ISO induced heart failure rats but received specific beta3-AR inhibitor SR59230A (ISO+ SR59230A group) for 6 weeks were included in this research. At the end of the study, echocardiography was performed, the ratio of left ventricular weight and body weight (LVW/BW) was calculated. The expression of beta3-AR ad UCP2 mRNA in myocardium were detected by reverse transcription-polymerase chain reaction (RT-PCR), the UCP2 protein in myocardium were detected by Western blot. The myocardial contents of creatine phosphate (PCr) and adenosine triphosphate (ATP) were measured by high performance liquid chromatography (HPLC).

RESULTSCompared with control group, the cardiac function was significantly reduced and myocardial beta3-AR mRNA significantly increased, UCP2 mRNA and protein were also significantly increased in ISO group, this change could be attenuated by the treatment with SR59230A, and the expression of myocardial UCP2 protein negatively correlated with the ratio of PCr/ATP.

CONCLUSIONIn the chronic stage of HF, the expression of UCP2 increases, which causes myocardial energy shortage, SR59230A improves myocardia energy efficiency and cardiac function by means of suppressing the expression of UCP2.

Adrenergic Antagonists ; pharmacology ; Animals ; Energy Metabolism ; Heart Failure ; metabolism ; Ion Channels ; metabolism ; Male ; Mitochondrial Proteins ; metabolism ; Myocardium ; metabolism ; Rats ; Rats, Wistar ; Receptors, Adrenergic, beta-3 ; metabolism ; Uncoupling Protein 2