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1.
Turk J Pharm Sci ; 21(1): 81-86, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38529568

RESUMO

Objectives: This study investigated the impact of a high-fat diet streptozotocin (STZ)-induced diabetes and dapagliflozin treatment on hepatic protein expression of CYP3A4. Materials and Methods: In our study, 34 male Sprague-Dawley rats were randomly divided into four groups: Control, high-fat diet and STZ-induced diabetes, dapagliflozin-treated control, and dapagliflozin-treated diabetes. In the microsomes obtained from the livers of these rats, the protein expression levels of CYP3A4 were determined by Western blotting. Results: Hepatic CYP3A4 protein expression levels in the control group treated with dapagliflozin were significantly decreased compared with those in the control group. In addition, hepatic CYP3A4 protein expression levels were decreased in dapagliflozin-treated diabetic Sprague-Dawley rats compared with those in both control and diabetic group rats, but the difference between the groups was not statistically significant. Conclusion: According to these two results, the use of dapagliflozin inhibited hepatic CYP3A4 protein expression.

2.
Pharmacol Ther ; 249: 108503, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37495021

RESUMO

We have performed a systematic review of studies reporting on the renal effects of SGLT2 inhibitors in rodent models of diabetes. In 105 studies, SGLT2 inhibitors improved not only the glycemic control but also various aspects of renal function in most cases. These nephroprotective effects were similarly reported whether treatment with the SGLT2 inhibitor started concomitant with the onset of diabetes (within 1 week), early after onset (1-4 weeks) or after nephropathy had developed (>4 weeks after onset) with the latter probably having the greatest translational value. They were observed across various animal models of type 1 and type 2 diabetes/obesity (4 and 23 models, respectively), although studies in the type 2 diabetes model of db/db mice more often had negative data than in other models. Among possibly underlying pathophysiological mechanisms of nephroprotection, treatment with SGLT2 inhibitors had beneficial effects on lipid metabolism, blood pressure, glomerulosclerosis as well as renal tubular fibrosis, apoptosis, oxidative stress, and inflammation. These pathomechanisms highly influence atherosclerosis and renal health, which are two major factors that lead to an enhanced mortality in patients with diabetes and/or chronic kidney disease. Interestingly, renal SGLT2 inhibitor effects did not always correlate with those on glucose homeostasis, particularly in a limited number of direct comparative studies with other anti-diabetic treatments, indicating that nephroprotection may at least partly occur by mechanisms other than improving glycemic control. Our analyses did not provide evidence for different nephroprotective efficacy between SGLT2 inhibitors. Importantly, only four of 105 studies reported on female animals, and none provided direct comparative data between sexes. We conclude that more data on female animals and more direct comparative studies with other anti-diabetic compounds and combinations of treatments are needed.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Feminino , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Rim/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
3.
Handb Exp Pharmacol ; 282: 219-239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37439847

RESUMO

Sexual dimorphism has been demonstrated to have an effect on various physiological functions. In this regard, researchers have investigated its impact on glucose homeostasis in both preclinical and clinical studies. Sex differences mainly arise from physiological factors such as sex hormones, body fat and muscle distribution, and sex chromosomes. The sexual dimorphism has also been studied in the context of diabetes. Reflecting the prevalence of the disease among the population, studies focusing on the sex difference in type 1 diabetes (T1D) are not common as the ones in type 2 diabetes (T2D). T1D is reported as the only major specific autoimmune disease that exhibits a male predominance. Clinical studies have demonstrated that impaired fasting glucose is more frequent in men whereas women more commonly exhibit impaired glucose tolerance. Understanding the sex difference in glucose homeostasis becomes more attractive when focusing on the findings that highlight sexual dimorphism on the efficacy or adverse effect profile of antidiabetic medications. Thus, in this chapter, we aimed to discuss the impact of sex on the glucose homeostasis both in health and in diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Feminino , Masculino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Caracteres Sexuais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glucose , Homeostase , Glicemia , Insulina
4.
Front Pharmacol ; 14: 1118730, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891264

RESUMO

Introduction: Diabetes often leads to lower urinary tract dysfunction. The most frequently assessed parameter of urinary bladder dysfunction in animal models of diabetes is an enlargement of the bladder, which is consistently observed in type 1 and less consistently in type 2 diabetes. The vast majority of studies on bladder weight in animal models of diabetes and obesity has been performed in males, and no studies have directly compared this outcome parameter between sexes. Methods: Therefore, we have compared bladder weight and bladder/body weight ratio in five mouse models of obesity and diabetes (RIP-LCMV, db/db, ob/ob (two studies), insulin receptor substrate 2 (IRS2) knock-out mice and mice on a high-fat diet; pre-specified secondary analysis of a previously reported study). Results: In a pooled analysis of the control groups of all studies, females exhibited slightly lower glucose levels, lower body weight, and lower bladder weight, but bladder/body weight ratio was similar in both sexes (0.957 vs. 0.986 mg/g, mean difference 0.029 [-0.06; 0.118]). Among the six diabetic/obese groups, bladder/body weight ratio was similar in both sexes in three but smaller in female mice in three other groups. The mRNA expression of a panel of genes implied in the pathophysiology of bladder enlargement and/or fibrosis and inflammation did not differ systematically between sexes. Conclusions: We conclude that sex differences in diabetes/obesity-associated bladder enlargement may be model dependent.

5.
Front Physiol ; 13: 923555, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003651

RESUMO

The urinary bladder is markedly enlarged in the type 1 diabetes mellitus model of streptozotocin-injected rats, which may contribute to the frequent diabetic uropathy. Much less data exists for models of type 2 diabetes. Diabetic polyuria has been proposed as the pathophysiological mechanism behind bladder enlargement. Therefore, we explored such a relationship across nine distinct rodent models of diabetes including seven models of type 2 diabetes/obesity by collecting data on bladder weight and blood glucose from 16 studies with 2-8 arms each; some studies included arms with various diets and/or pharmacological treatments. Data were analysed for bladder enlargement and for correlations between bladder weight on the one and glucose levels on the other hand. Our data confirm major bladder enlargement in streptozotocin rats and minor if any enlargement in fructose-fed rats, db/db mice and mice on a high-fat diet; enlargement was present in some of five not reported previously models. Bladder weight was correlated with blood glucose as a proxy for diabetic polyuria within some but not other models, but correlations were moderate to weak except for RIP-LCMV mice (r 2 of pooled data from all studies 0.0621). Insulin levels also failed to correlate to a meaningful extent. Various diets and medications (elafibranor, empagliflozin, linagliptin, semaglutide) had heterogeneous effects on bladder weight that often did not match their effects on glucose levels. We conclude that the presence and extent of bladder enlargement vary markedly across diabetes models, particularly type 2 diabetes models; our data do not support the idea that bladder enlargement is primarily driven by glucose levels/glucosuria.

6.
J Pharm Biomed Anal ; 219: 114966, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35908414

RESUMO

The aim of the present study is to develop the polymeric nanoparticulate drug delivery systems of piroxicam and to evaluate the in-vitro characteristics such as entrapment efficiency, surface morphology, in-vitro drug release performance, etc. For this reason, a novel HPLC methodology was developed for the determination of piroxicam from its bulk form, pharmaceutical preparation, and nanoparticulate delivery systems. Furthermore, the developed formulation was applied to the rats and the biological samples (plasma, liver, heart, spleen, kidney, and lung homogenates) were analyzed by the developed HPLC method following a salting-out assisted liquid-liquid extraction strategy for the first time in the literature. A Kinetex C18 analytical column (150 mm × 4.6 mm i.d., 5 µm) was used as a stationary phase with a 0.8 mL/min flow rate of acetonitrile: phosphate buffer (40:60, v/v), the column oven was adjusted to 40 °C and detection wavelength is set to 360 nm. Developed method were validated as per selectivity, linearity, LOD, LOQ, precision, and accuracy specified in the International Council for Harmonisation guidelines. As a result of the present study, it has been shown that the analysis of piroxicam from the bulk form, pharmaceutical preparation, developed polymeric-based drug delivery system, and biological samples can be successfully performed and no interferences were observed in any matrix. The developed method was also successfully utilized to study the tissue distribution of piroxicam in rats.


Assuntos
Extração Líquido-Líquido , Piroxicam , Animais , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Preparações Farmacêuticas , Polímeros , Ratos
7.
Naunyn Schmiedebergs Arch Pharmacol ; 395(8): 887-906, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35545721

RESUMO

Dysfunction of the lower urinary tract (LUT) including urinary bladder and urethra (and prostate in men) is one of the most frequent complications of diabetes and can manifest as overactive bladder, underactive bladder, urinary incontinence, and as aggravated symptoms of benign prostate hyperplasia. We have performed a selective literature search to review existing evidence on efficacy of classic medications for the treatment of LUT dysfunction in diabetic patients and animals, i.e., α1-adrenoceptor and muscarinic receptor antagonists, ß3-adrenoceptor agonists, and phosphodiesterase type 5 inhibitors. Generally, these agents appear to have comparable efficacy in patients and/or animals with and without diabetes. We also review effects of antidiabetic medications on LUT function. Such studies have largely been performed in animal models. In the streptozotocin-induced models of type 1 diabetes, insulin can prevent and reverse alterations of morphology, function, and gene expression patterns in bladder and prostate. Typical medications for the treatment of type 2 diabetes have been studied less often, and the reported findings are not yet sufficient to derive robust conclusions. Thereafter, we review animal studies with emerging medications perhaps targeting diabetes-associated LUT dysfunction. Data with myoinositol, daidzein, and with compounds that target oxidative stress, inflammation, Rac1, nerve growth factor, angiotensin II receptor, serotonin receptor, adenosine receptor, and soluble guanylyl cyclase are not conclusive yet, but some hold promise as potential treatments. Finally, we review nonpharmacological interventions in diabetic bladder dysfunction. These approaches are relatively new and give promising results in preclinical studies. In conclusion, the insulin data in rodent models of type 1 diabetes suggest that diabetes-associated LUT function can be mostly or partially reversed. However, we propose that considerable additional experimental and clinical studies are needed to target diabetes itself or pathophysiological changes induced by chronic hyperglycemia for the treatment of diabetic uropathy.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Insulinas , Animais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Insulinas/metabolismo , Masculino , Receptores Adrenérgicos alfa 1/metabolismo , Bexiga Urinária/metabolismo
8.
Pharmacology ; 107(1-2): 116-121, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34781292

RESUMO

Fenoterol is a ß2-adrenoceptor (AR)-selective agonist that is commonly used to investigate relaxation responses mediated by ß2-AR in smooth muscle preparations. Some data have questioned this because fenoterol had low potency in the rat urinary bladder when a muscarinic agonist was used as a pre-contraction agent and because some investigators proposed that fenoterol may act in part via ß3-AR. We designed the present study to investigate whether fenoterol is a proper pharmacological tool to study ß2-AR-mediated relaxation responses in the rat urinary bladder. Firstly, we have compared the effect of pre-contraction agents on fenoterol potency and found that fenoterol potency was about 1.5 log units greater against KCl than carbachol (pEC50 7.19 ± 0.66 and 5.62 ± 1.09 of KCl and of carbachol, respectively). To test the selectivity of fenoterol, we have determined the effects of the ß2-AR antagonist ICI 118,551 and the ß3-AR antagonist L 748,337 on relaxation responses to fenoterol. While 300 nM L 748,337 had little effect on the potency of fenoterol (pEC50 6.56 ± 0.25 and 6.33 ± 0.61 in the absence and presence of L 748,337, respectively), the relaxation curve for fenoterol was right-shifted in the presence 300 nM ICI 118,551 (pEC50 5.03 ± 0.18). Thus, we conclude that fenoterol is a proper pharmacological tool to assess ß2-AR-mediated responses in the rat urinary bladder and most likely in other smooth-muscle preparations containing multiple subtypes of the ß-AR.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Fenoterol/farmacologia , Bexiga Urinária/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Aminofenóis/farmacologia , Aminofenóis/uso terapêutico , Animais , Carbacol/farmacologia , Carbacol/uso terapêutico , Feminino , Fenoterol/uso terapêutico , Masculino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Cloreto de Potássio/uso terapêutico , Propanolaminas/farmacologia , Propanolaminas/uso terapêutico , Ratos Sprague-Dawley , Ratos Wistar , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
10.
Turk J Med Sci ; 51(2): 864-872, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33185366

RESUMO

Background/aim: Dipeptidyl peptidase-4 (DPP4) inhibitors, a class of oral antidiabetic drugs, have been shown to be protective on the vascular system because of their antiinflammatory, antiatherosclerotic, and vasodilatory effects. ß2-adrenoceptors (ß2-ARs) mediate the vasorelaxation in the aorta. However, ß3-adrenoceptor-mediated relaxation has not been studied in diabetic aorta yet. Thus, we aimed to study the effect of sitagliptin treatment on ß2- and ß3-adrenoceptor-mediated relaxations in the diabetic rat aorta. Materials and methods: Eight-week old Sprague Dawley rats were divided into three groups: control, diabetic, sitagliptin treated diabetic. Diabetes was induced by injection of streptozotocin (35 or 40 mg/kg, intraperitoneally). After 10 weeks of diabetes, some of the diabetic rats were treated with sitagliptin (orally, 10mg/kg/day). ß2- and ß3-AR-mediated relaxation responses were evaluated by using isoprenaline and CL 316,243, respectively. ß3-AR-mediated relaxation experiments were repeated in presence of L-NAME. Western blotting and immunohistochemistry were performed to determine the abundance of ß3-adrenoceptor and endothelial nitric oxide synthase (eNOS). Results: The isoprenaline-mediated relaxation response was impaired in the diabetic group and sitagliptin treatment did not improve it. There was no significant change in CL316,243 mediated-relaxation or protein expression of ß3-ARs among the groups. However, the ratio of phosphorylated eNOS/NOS protein was increased markedly in the sitagliptin treated group, which points the stimulating effect of this drug towards the eNOS pathway. Conclusion: Our results indicate that sitagliptin treatment does not alter ß-AR-mediated relaxation in streptozotocin-diabetic rat aorta; however, it significantly stimulates the eNOS pathway. Future studies are needed to clarify the relationship between the eNOS pathway and DPP-4 inhibition.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Receptores Adrenérgicos/uso terapêutico , Fosfato de Sitagliptina/farmacologia , Estreptozocina/efeitos adversos , Animais , Aorta , Isoproterenol , Óxido Nítrico , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2
11.
Cells ; 9(12)2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256212

RESUMO

Diabetes is a chronic, endocrine disorder that effects millions of people worldwide. Cardiovascular complications are the major cause of diabetes-related morbidity and mortality. Cardiac ß1- and ß2-adrenoceptor (AR) stimulation mediates positive inotropy and chronotropy, whereas ß3-AR mediates negative inotropic effect. Changes in ß-AR responsiveness are thought to be an important factor that contributes to the diabetic cardiac dysfunction. Diabetes related changes in ß-AR expression, signaling, and ß-AR mediated cardiac function have been studied by several investigators for many years. In the present review, we have screened PubMed database to obtain relevant articles on this topic. Our search has ended up with wide range of different findings about the effect of diabetes on ß-AR mediated changes both in molecular and functional level. Considering these inconsistent findings, the effect of diabetes on cardiac ß-AR still remains to be clarified.


Assuntos
Diabetes Mellitus/metabolismo , Cardiopatias/metabolismo , Receptores Adrenérgicos beta/metabolismo , Transdução de Sinais/fisiologia , Coração/fisiologia , Humanos , Miocárdio/metabolismo
12.
Cells ; 9(11)2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158106

RESUMO

As heart failure (HF) is a devastating health problem worldwide, a better understanding and the development of more effective therapeutic approaches are required. HF is characterized by sympathetic system activation which stimulates α- and ß-adrenoceptors (ARs). The exposure of the cardiovascular system to the increased locally released and circulating levels of catecholamines leads to a well-described downregulation and desensitization of ß-ARs. However, information on the role of α-AR is limited. We have performed a systematic literature review examining the role of both cardiac and vascular α1-ARs in HF using 5 databases for our search. All three α1-AR subtypes (α1A, α1B and α1D) are expressed in human and animal hearts and blood vessels in a tissue-dependent manner. We summarize the changes observed in HF regarding the density, signaling and responses of α1-ARs. Conflicting findings arise from different studies concerning the influence that HF has on α1-AR expression and function; in contrast to ß-ARs there is no consistent evidence for down-regulation or desensitization of cardiac or vascular α1-ARs. Whether α1-ARs are a therapeutic target in HF remains a matter of debate.


Assuntos
Vasos Sanguíneos/metabolismo , Insuficiência Cardíaca/metabolismo , Miocárdio/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Insuficiência Cardíaca/genética , Humanos , Modelos Biológicos , Receptores Adrenérgicos alfa 1/genética , Transdução de Sinais
13.
J Diabetes Metab Disord ; 19(2): 1157-1164, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33520832

RESUMO

Reactive oxygen species (ROS) and lipid peroxidation (LPO) levels may increase in diabetic state and lead to oxidative stress, which plays a critical role in the progression of diabetes. There are various sources of ROS, including cytochrome P450 monooxygenases (CYP450s), which may be modulated in terms of their activities and expressions under diabetic conditions. This study is aimed to investigate the effects of streptozotocin-induced diabetes and insulin treatment on hepatic cytochrome P450 1A1 (CYP1A1) and cytochrome P450 2E1 (CYP2E1) activities and LPO levels. Methods: CYP1A1 and CYP2E1 activities were measured with ethoxyresorufin O-deethylase and p-nitrophenol hydroxylase activities, respectively. LPO levels were then corroborated via thiobarbituric acid reactive substances. Results: In diabetic rats, a marked 2.1- and 2.4-fold increase in hepatic CYP1A1 activity and 1.8- and 1.6-fold increase in hepatic CYP2E1 activity were observed compared to controls and insulin-treated diabetic rats, respectively. Hepatic LPO levels in diabetic rats did not significantly change compared to controls. However, in insulin-treated diabetic rats, LPO levels are 0.92- and 0.89-fold remarkably decrease compared to controls and diabetics, respectively. Conclusion: The present study suggests that insulin might have a useful role in the modulation of CYP1A1 and CYP2E1 activities as well as LPO levels in the liver of diabetic rats.

14.
Naunyn Schmiedebergs Arch Pharmacol ; 393(2): 243-251, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31511953

RESUMO

Organ bath experiments are a key technology to assess contractility of smooth muscle. Despite efforts to standardize tissue specimen sizes, they vary to a certain degree. As it appears obvious that a larger piece of tissue should develop greater force, most investigators normalize contraction data for specimen size. However, they lack agreement which parameter should be used as denominator for normalization. A pre-planned analysis of data from a recent study was used to compare denominators used for normalization, i.e., weight, length, and cross-sectional area. To increase robustness, we compared force with denominator in correlation analysis and also coefficient of variation with different denominators. This was done concomitantly with urinary bladder strips and aortic rings and with multiple contractile stimuli. Our urinary bladder data show that normalization for strip weight yielded the tightest but still only moderate correlation (e.g., r2 = 0.3582 for peak carbachol responses based on 188 strips). In aorta, correlations were even weaker (e.g., r2 = 0.0511 for plateau phenylephrine responses normalized for weight based on 200 rings). Normalization for strip size is less effective in reducing data variability than previously assumed; the normalization denominator of choice must be identified separately for each preparation.


Assuntos
Aorta/fisiologia , Contração Muscular , Bexiga Urinária/fisiologia , Animais , Aorta/efeitos dos fármacos , Carbacol/farmacologia , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Fenilefrina/farmacologia , Cloreto de Potássio/farmacologia , Ratos Sprague-Dawley , Manejo de Espécimes , Bexiga Urinária/efeitos dos fármacos
15.
Naunyn Schmiedebergs Arch Pharmacol ; 393(2): 141-146, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31853614

RESUMO

ß3-Adrenoceptors exhibit a restricted expression pattern, particularly in humans. However, they have been found to be upregulated in various cancers and under several conditions associated with hypoperfusion such as congestive heart failure and diabetes for instance in the heart and other tissues. These conditions are frequently associated with hypoxia. Furthermore, direct induction of hypoxia has consistently been reported to cause upregulation of ß3-adrenoceptors across various tissues of multiple species including humans, rats, dogs, and fish. While a canonical hypoxia-response element in the promoter of the human ß3-adrenoceptor gene may play a role in this, no such sequence was found in rodent homologs. Moreover, not all upregulation of ß3-adrenoceptor protein is accompanied by increased expression of corresponding mRNA, indicating that the upregulation may involve factors other than transcriptional changes. We propose that upregulation of ß3-adrenoceptors at the mRNA and/or protein level is a general marker of hypoxic conditions. Moreover, it may be an additional pathway whereby cells and tissues adapt to reduced oxygen levels.


Assuntos
Hipóxia/metabolismo , Receptores Adrenérgicos beta 3/metabolismo , Animais , Biomarcadores/metabolismo , Humanos , Receptores Adrenérgicos beta 3/genética , Regulação para Cima
16.
Front Pharmacol ; 10: 911, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474866

RESUMO

Hypertrophy and dysfunction of the urinary bladder are consistently observed in animal models of type 1 and less consistently in those of type 2 diabetes. We have tested the effects of mild hyperglycemia (n = 10 per group) in a randomized, blinded study and, in a blinded pilot study, of type 2 diabetes (n = 6 per group) and its treatment with dapagliflozin (1 mg/kg per day) on weight, contraction, and relaxation of the rat bladder. Based on a combination of high-fat diet and a low dose of streptozotocin, animals in the main study reached a mean peak blood glucose level of about 300 mg/dl, which declined to 205 mg/dl at study end. This was associated with a small, if any, increase in bladder weight. In a pooled analysis of all animals of the main and the pilot study, we detected a correlation of moderate strength between blood glucose and bladder weight (r 2 = 0.2013; P = 0.0003 for Pearson correlation coefficient). Neither the main nor the pilot study found evidence for an altered contractility (responses to carbachol or KCl) or relaxation (responses to isoprenaline, fenoterol, CL 316,243, or forskolin). Treatment with dapagliflozin in the absence of hyperglycemia increased diuresis in the main study by 43% relative to control and increased bladder weight by 15% in the pooled groups of both studies (post hoc analysis). We conclude that mild hyperglycemia has no major effects on bladder hypertrophy or function.

17.
Eur J Pharmacol ; 858: 172468, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31226249

RESUMO

As heart failure (HF) is a growing public health problem worldwide, rapid therapeutic development is required to improve HF management. Decreased myocardial contractility in HF is associated with the persistent sympathetic activation of ß1/ß2-adrenoceptors (ß1/ß2-ARs). Although it is initially activated to compensate for a decline in myocardial contractility, it plays a pivotal role in organ damage and functional deterioration over time, resulting in the desensitization of receptors involved. The third ß-AR subtype, ß3-AR, is resistant to desensitization, and as a result, the expression of this subtype is enhanced in human failing myocardium. In addition, this upregulation and the stimulation of this subtype have been demonstrated to mediate cardioprotective effects such as antihypertrophic, antioxidant and antifibrotic effects via various signaling pathways in different cell types. However, the role of this attractive therapeutic intervention in heart diseases must be clarified through clinical trials.


Assuntos
Cardiopatias/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Receptores Adrenérgicos beta 3/metabolismo , Antagonistas de Receptores Adrenérgicos beta 3/farmacologia , Antagonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Cardiopatias/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Humanos
18.
Br J Pharmacol ; 176(14): 2482-2495, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30801686

RESUMO

As ß3 -adrenoceptors were first demonstrated to be expressed in adipose tissue they have received much attention for their metabolic effects in obesity and diabetes. After the existence of this subtype had been suggested to be present in the heart, studies focused on its role in cardiac function. While the presence and functional role of ß3 -adrenoceptors in the heart has not uniformly been detected, there is a broad consensus that they become up-regulated in pathological conditions associated with increased sympathetic activity such as heart failure and diabetes. When detected, the ß3 -adrenceptor has been demonstrated to mediate negative inotropic effects in an inhibitory G protein-dependent manner through the NO-cGMP-PKG signalling pathway. Whether these negative inotropic effects provide protection from the adverse effects induced by overstimulation of ß1 /ß2 -adrenoceptors or in themselves are potentially harmful is controversial, but ongoing clinical studies in patients with congestive heart failure are testing the hypothesis that ß3 -adrenceptor agonism has a beneficial effect. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Receptores Adrenérgicos beta 3/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Humanos
19.
Neurourol Urodyn ; 37(8): 2346-2360, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30152546

RESUMO

AIMS: To explore whether the bladder hypertrophy consistently seen in rats upon streptozotocin injection also occurs in other animal models of type 1 or 2 diabetes and how hypertrophy is linked to functional alterations of the urinary bladder. METHODS: A systematic search for the key word combination "diabetes," "bladder," and "hypertrophy" was performed in PubMed; additional references were identified from reference lists of those publications. All papers were systematically extracted for relevant information. RESULTS: Models other than streptozotocin-injected rats and female animals have been poorly studied. Most animal models of diabetes exhibit less bladder hypertrophy as compared to streptozotocin-injected rats. However, this is not linked to type 1 versus 2 diabetes models, and type 2 models with comparable elevation of blood glucose may exhibit strong or only minor hypertrophy. Bladder dysfunction is frequently observed in experimental diabetes and mostly manifests as increased compliance but does not segregate with hypertrophy. It may at least partly reflect the need to handle large amounts of urine in models associated with major elevation of blood glucose. CONCLUSIONS: To better understand the relevance of bladder hypertrophy in many models of experimental diabetes, more studies in models of type 2 diabetes are urgently needed. Moreover, the role of factors other than hypertrophy in the genesis of bladder dysfunction requires further exploration.


Assuntos
Diabetes Mellitus Experimental/complicações , Modelos Animais , Doenças da Bexiga Urinária/patologia , Animais , Hipertrofia/etiologia , Ratos , Doenças da Bexiga Urinária/etiologia
20.
Neurourol Urodyn ; 37(4): 1212-1219, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29392751

RESUMO

AIMS: To better understand the genesis and consequences of urinary bladder hypertrophy in animal models of diabetes. This part of a three-article series will analyze urinary bladder hypertrophy in the diabetes mellitus type 1 model of rats injected with streptozotocin (STZ). METHODS: A systematic search for the key word combination "diabetes," "bladder" and "hypertrophy" was performed in PubMed; additional references were identified from reference lists of those publications. All papers were systematically extracted for relevant information. RESULTS: A total of 39 studies were identified that quantitatively reported on bladder hypertrophy in rats upon injection of STZ; of which several reported on multiple time points yielding a total of 83 group comparisons. Bladder hypertrophy was found consistently, being fully developed as early as 1 week after STZ injection (bladder weight 188 ± 59% of matched control). Hypertrophy was similar across sexes and STZ doses (35-40 vs 50-65 mg/kg) but appeared greater with Wistar rats than other rat strains. The extent of bladder hypertrophy was not correlated to blood glucose concentrations, but normalization of blood glucose concentration by insulin treatment starting early after STZ injection prevented hypertrophy; insulin treatment starting after hypertrophy had established largely reversed it. CONCLUSIONS: Bladder size approximately doubles after STZ injection in rats; the extent of hypertrophy is not linked to the severity of hyperglycemia but largely reversible by restoration of euglycemia.


Assuntos
Diabetes Mellitus Experimental/patologia , Doenças da Bexiga Urinária/patologia , Animais , Peso Corporal , Diabetes Mellitus Experimental/complicações , Ratos , Ratos Wistar , Doenças da Bexiga Urinária/etiologia
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