24 research outputs found
Bradykinin -induced vasodilatation : Role of age, ACE1-inhibitory peptide, mas- and bradykinin receptors
Bradykinin exerts its vascular actions via two types of receptors, the non-constitutively expressed bradykinin receptor type 1 (BR1) and the constitutive type 2 receptor (BR2). Bradykinin-induced vasorelaxation is age-dependent, a phenomenon related to the varying amounts of BR1 and BR2 in the vasculature. Isoleucine-proline-proline (Ile-Pro-Pro), a bioactive tripeptide, lowers elevated blood pressure and improves impaired endothelium-dependent vasorelaxation in hypertensive rats. It inhibits angiotensin converting enzyme 1 (ACE1). Other mechanisms of action have also been postulated. The aims of the study were to clarify the underlying mechanisms of the age-dependency of bradykinin-induced vasodilatation such as the roles of the two bradykinin receptors, themas-receptor and synergism with Ile-Pro-Pro. The vascular response studies were conducted using mesenteric artery and aorta rings from normotensive 6 wk. (young) and 22 wk. (old) Wistar rats. Cumulative dosing of acetylcholine, bradykinin and angiotensin(1-7) (Ang(1-7))were tested in phenylephrine-induced vasoconstriction with or without 10 min pre-incubation with antagonists against BR1-, BR2- or mas-receptors,Ang(1-7) or ACE1-inhibitors captopril and Ile-Pro-Pro. The bradykinin-induced vasorelaxation in vitro was age-dependent and it was improved by pre incubation with Ile-Pro-Pro, especially in old rats with endothelial dysfunction. The mas-receptor antagonist, D-Pro7-Ang(1-7) abolished bradykinin-induced relaxation totally. Interestingly, BR1 and BR2 antagonists only slightly reduced bradykinin-induced vasorelaxation, as an evidence for the involvement of other mechanisms in addition to receptor activation. In conclusion, bradykinin-induced vasorelaxation was age -dependent and He-Pro-Pro improved it. Mas receptor antagonist abolished relaxation while bradykinin receptor antagonist only slightly reduced it, suggesting that bradykinin-induced vasorelaxation is regulated also by other mechanisms than the classical BR1/BR2 pathway. (C) 2016 Elsevier Inc: All rights reserved.Peer reviewe
Role of Lipids and Lipid Metabolism in Prostate Cancer Progression and the Tumorâs Immune Environment
Modulation of lipid metabolism during cancer development and progression is one of the hallmarks of cancer in solid tumors; its importance in prostate cancer (PCa) has been demonstrated in numerous studies. Lipid metabolism is known to interact with androgen receptor signaling, an established driver of PCa progression and castration resistance. Similarly, immune cell infiltration into prostate tissue has been linked with the development and progression of PCa as well as with disturbances in lipid metabolism. Immuno-oncological drugs inhibit immune checkpoints to activate immune cellsâ abilities to recognize and destroy cancer cells. These drugs have proved to be successful in treating some solid tumors, but in PCa their efficacy has been poor, with only a small minority of patients demonstrating a treatment response. In this review, we first describe the importance of lipid metabolism in PCa. Second, we collate current information on how modulation of lipid metabolism of cancer cells and the surrounding immune cells may impact the tumorâs immune responses which, in part, may explain the unimpressive results of immune-oncological treatments in PCa
Development, validation, and application of a fast, simple, and robust SPE-based LC-MS/MS method for quantification of angiotensin I-converting enzyme inhibiting tripeptides Val-Pro-Pro, Ile-Pro-Pro, and Leu-Pro-Pro in yoghurt and other fermented dairy products
Dairy products are an important part of a nutritionally balanced diet as their constituents can affect the human state of health. By inhibiting the angiotensin I-converting enzyme, the tripeptides Val-Pro-Pro, Ile-Pro-Pro, and Leu-Pro-Pro can lower blood pressure. As these peptides are produced during fermentation, they are found in various dairy products like cheese, yoghurt, etc., but except for cheese only little is known about their content. To investigate how other dairy products contribute to a supply of these antihypertensive peptides, we developed and validated a fast and sensitive assay for quantification of the three tripeptides with LC-MS/MS combined with a simple protocol for extraction and SPE-purification from yoghurt, curd, or other products. Finally, the entire method was successfully applied to survey peptide concentrations in samples from local dairies and thus expands our awareness on the content of antihypertensive peptides in our food. (C) 2019 Elsevier Ltd. All rights reserved.Peer reviewe
Age-related changes in the local intestinal renin-angiotensin system in normotensive and spontaneously hypertensive rats
Reniini-angiotensiinijÀrjestelmÀn (RAS) paikallisia toimintoja on kuvattu monissa
kudoksissa. RAS:n fysiologinen kokonaisvaikutus on riippuvainen kahden vastavaikuttavan
biokemiallisen akselin suhteellisesta aktiivisuudesta. Klassisen akselin muodostavat
angiotensiinikonvertaasi (ACE), angiotensiini II (Ang II) ja tyypin 1 angiotensiini II -reseptori
(AT1R). Vaihtoehtoiseen akseliin kuuluvat angiotensiinikonvertaasi 2 [ACE2], angiotensiini
1-7 [Ang (1-7)] sekÀ Mas-reseptori (MAS). Suoliston paikallinen RAS toimii parakriinisena
sÀÀtelijÀnÀ ja osallistuu tulehduksen sÀÀtelyyn. JÀrjestelmÀn vaikutus paikalliseen
kudokseen riippuu klassisen ja vaihtoehtoisen akselin aktiivisuuksien suhteesta. Klassinen
akseli edistÀÀ ja vaihtoehtoinen akseli lievittÀÀ tulehdusta. Paikallisten reniini-
angiotensiinijÀrjestelmien toiminnan ja akselien vÀlisen suhteen tiedetÀÀn muuttuvan
ikÀÀntyessÀ. Asiaa ei kuitenkaan aiemmin ole tutkittu suoliston osalta. Tutkimukseni kartoitti
paikallisen RAS:n ilmentymistÀ nuorten ja vanhojen rottien suolistossa. Tutkin jejunumia ja
paksusuolta. PÀÀlöydökseni oli, ettÀ vanhempien rottien suolistossa ACE:n ja ACE2:n suhde
oli korkeampi, sekÀ entsyymiaktiivisuudella ettÀ proteiinikonsentraatiolla mitattuna. NÀyttÀÀ
siltÀ, ettÀ ikÀÀntymisen myötÀ rottien suoliston paikallisen reniini-angiotensiinijÀrjestelmÀn
toiminta painottuu klassiselle ACE-vÀlitteiselle akselille. On mahdollista, ettÀ paikallisen
RAS:n toiminnan painottuminen ACE-vÀlitteiselle akselille liittyy siihen, ettÀ iÀn myötÀ
suolistossa tapahtuu tulehduksen ja sidekudoksen muodostuksen lisÀÀntymistÀ
Antihypertensive drug use and prostate cancer-specific mortality in Finnish men
The aim of this study was to investigate pre- and post-diagnostic use of antihypertensive drugs on prostate cancer (PCa)-specific survival and the initiation of androgen deprivation therapy (ADT). The cohort investigated 8,253 PCa patients with 837 PCa-specific deaths during the median follow-up of 7.6 years after diagnosis. Information on drug use, cancer incidence, clinical features of PCa, and causes of death was collected from Finnish registries. Hazard ratios with 95% confidence intervals were calculated using Cox regression with antihypertensive drug use as a time-dependent variable. Separate analyses were performed on PCa survival related to pre- and post-diagnostic use of drugs and on the initiation of ADT. Antihypertensive drug use overall was associated with an increased risk of PCa-specific death (Pre-PCa: 1.21 (1.04â1.4), Post-PCa: 1.2 (1.02â1.41)). With respect to the separate drug groups, angiotensin II type 1 receptor (ATr) blockers, were associated with improved survival (Post-PCa: 0.81 (0.67â0.99)) and diuretics with an increased risk (Post-PCa: 1.25 (1.05â1.49)). The risk of ADT initiation was slightly higher among antihypertensive drug users as compared to non-users. In conclusion, this study supports anti-cancer effect of ATr blockers on PCa prognosis and this should be investigated further in controlled clinical trials.Peer reviewe
Role of Lipids and Lipid Metabolism in Prostate Cancer Progression and the Tumorâs Immune Environment
Modulation of lipid metabolism during cancer development and progression is one of the hallmarks of cancer in solid tumors; its importance in prostate cancer (PCa) has been demonstrated in numerous studies. Lipid metabolism is known to interact with androgen receptor signaling, an established driver of PCa progression and castration resistance. Similarly, immune cell infiltration into prostate tissue has been linked with the development and progression of PCa as well as with disturbances in lipid metabolism. Immuno-oncological drugs inhibit immune checkpoints to activate immune cellsâ abilities to recognize and destroy cancer cells. These drugs have proved to be successful in treating some solid tumors, but in PCa their efficacy has been poor, with only a small minority of patients demonstrating a treatment response. In this review, we first describe the importance of lipid metabolism in PCa. Second, we collate current information on how modulation of lipid metabolism of cancer cells and the surrounding immune cells may impact the tumorâs immune responses which, in part, may explain the unimpressive results of immune-oncological treatments in PCa.publishedVersionPeer reviewe
Randomised double-blind phase 3 clinical study testing impact of atorvastatin on prostate cancer progression after initiation of androgen deprivation therapy : study protocol
Introduction Blood cholesterol is likely a risk factor for prostate cancer prognosis and use of statins is associated with lowered risk of prostate cancer recurrence and progression. Furthermore, use of statins has been associated with prolonged time before development of castration resistance (CR) during androgen deprivation therapy (ADT) for prostate cancer. However, the efficacy of statins on delaying castration-resistance has not been tested in a randomised placebo-controlled setting. This study aims to test statins' efficacy compared to placebo in delaying development of CR during ADT treatment for primary metastatic or recurrent prostate cancer. Secondary aim is to explore effect of statin intervention on prostate cancer mortality and lipid metabolism during ADT. Methods and analysis In this randomised placebo-controlled trial, a total of 400 men with de novo metastatic prostate cancer or recurrent disease after primary treatment and starting ADT will be recruited and randomised 1:1 to use daily 80 mg of atorvastatin or placebo. All researchers, study nurses and patients will be blinded throughout the trial. Patients are followed until disease recurrence or death. Primary outcome is time to formation of CR after initiation of ADT. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and trigyserides) are analysed to test whether changes in serum cholesterol parameters during ADT predict length of treatment response. Furthermore, the trial will compare quality of life, cardiovascular morbidity, changes in blood glucose and circulating cell-free DNA, and urine lipidome during trial. Ethics and dissemination This study is approved by the Regional ethics committees of the Pirkanrnaa Hospital District, Science centre, Tampere, Finland (R18065M) and Tarto University Hospital, Tarto, Estonia (319/T-6). All participants read and sign informed consent form before study entry. After publication of results for the primary endpoints, anonymised summary metadata and statistical code will be made openly available. The data will not include any information that could make it possible to identify a given participant.Peer reviewe
How Well do Polygenic Risk Scores Identify Men at High Risk for Prostate Cancer? : Systematic Review and Meta-Analysis
OBJECTIVES: Genome-wide association studies have revealed over 200 genetic susceptibility loci for prostate cancer (PCa). By combining them, polygenic risk scores (PRS) can be generated to predict risk of PCa. We summarize the published evidence and conduct meta-analyses of PRS as a predictor of PCa risk in Caucasian men. PATIENTS AND METHODS: Data were extracted from 59 studies, with 16 studies including 17 separate analyses used in the main meta-analysis with a total of 20,786 cases and 69,106 controls identified through a systematic search of ten databases. Random effects meta-analysis was used to obtain pooled estimates of area under the receiver-operating characteristic curve (AUC). Meta-regression was used to assess the impact of number of single-nucleotide polymorphisms (SNPs) incorporated in PRS on AUC. Heterogeneity is expressed as I2 scores. Publication bias was evaluated using funnel plots and Egger tests. RESULTS: The ability of PRS to identify men with PCa was modest (pooled AUC 0.63, 95% CI 0.62-0.64) with moderate consistency (I2 64%). Combining PRS with clinical variables increased the pooled AUC to 0.74 (0.68-0.81). Meta-regression showed only negligible increase in AUC for adding incremental SNPs. Despite moderate heterogeneity, publication bias was not evident. CONCLUSION: Typically, PRS accuracy is comparable to PSA or family history with a pooled AUC value 0.63 indicating mediocre performance for PRS alone.publishedVersionPeer reviewe
Randomised double-blind phase 3 clinical study testing impact of atorvastatin on prostate cancer progression after initiation of androgen deprivation therapy: study protocol
Introduction Blood cholesterol is likely a risk factor for prostate cancer prognosis and use of statins is associated with lowered risk of prostate cancer recurrence and progression. Furthermore, use of statins has been associated with prolonged time before development of castration resistance (CR) during androgen deprivation therapy (ADT) for prostate cancer. However, the efficacy of statins on delaying castration-resistance has not been tested in a randomised placebo-controlled setting.This study aims to test statinsâ efficacy compared to placebo in delaying development of CR during ADT treatment for primary metastatic or recurrent prostate cancer. Secondary aim is to explore effect of statin intervention on prostate cancer mortality and lipid metabolism during ADT.Methods and analysis In this randomised placebo-controlled trial, a total of 400 men with de novo metastatic prostate cancer or recurrent disease after primary treatment and starting ADT will be recruited and randomised 1:1 to use daily 80âmg of atorvastatin or placebo. All researchers, study nurses and patients will be blinded throughout the trial. Patients are followed until disease recurrence or death. Primary outcome is time to formation of CR after initiation of ADT. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and trigyserides) are analysed to test whether changes in serum cholesterol parameters during ADT predict length of treatment response. Furthermore, the trial will compare quality of life, cardiovascular morbidity, changes in blood glucose and circulating cell-free DNA, and urine lipidome during trial.Ethics and dissemination This study is approved by the Regional ethics committees of the Pirkanmaa Hospital District, Science centre, Tampere, Finland (R18065M) and Tarto University Hospital, Tarto, Estonia (319/T-6). All participants read and sign informed consent form before study entry. After publication of results for the primary endpoints, anonymised summary metadata and statistical code will be made openly available. The data will not include any information that could make it possible to identify a given participant.</p