We completed a multicenter study of the effects of pomegranate cold-pressed (Oil) or supercritical CO(2)-extracted (S) seed oil, fermented juice polyphenols (W), and pericarp polyphenols (P) on human prostate cancer cell xenograft growth in vivo, and/or proliferation, cell cycle distribution, apoptosis, gene expression, and invasion across Matrigel, in vitro. Oil, W, and P each acutely inhibited in vitro proliferation of LNCaP, PC-3, and DU 145 human cancer cell lines. The dose of P required to inhibit cell proliferation of the prostate cancer cell line LNCaP by 50% (ED(50)) was 70 microg/mL, whereas normal prostate epithelial cells (hPrEC) were significantly less affected (ED(50) = 250 g/mL). These effects were mediated by changes in both cell cycle distribution and induction of apoptosis. For example, the androgen-independent cell line DU 145 showed a significant increase from 11% to 22% in G(2)/M cells (P <.05) by treatment with Oil (35 microg/mL) with a modest induction of apoptosis. In other cell lines/treatments, the apoptotic response predominated, for example, in PC-3 cells treated with P, at least partially through a caspase 3-mediated pathway. These cellular effects coincided with rapid changes in mRNA levels of gene targets. Thus, 4-hour treatment of DU 145 cells with Oil (35 microg/mL) resulted in significant 2.3 +/- 0.001-fold (mean +/- SEM) up-regulation of the cyclin-dependent kinase inhibitor p21((waf1/cip1)) (P <.01) and 0.6 +/- 0.14-fold down-regulation of c-myc (P <.05). In parallel, all agents potently suppressed PC-3 invasion through Matrigel, and furthermore P and S demonstrated potent inhibition of PC-3 xenograft growth in athymic mice. Overall, this study demonstrates significant antitumor activity of pomegranate-derived materials against human prostate cancer.
BackgroundRemote ischemic preconditioning (RIPC) has been shown to enhance the tolerance of remote organs to cope with a subsequent ischemic event. We hypothesized that RIPC reduces postoperative neurocognitive dysfunction (POCD) in patients undergoing complex cardiac surgery.MethodsWe conducted a prospective, randomized, double-blind, controlled trial including 180 adult patients undergoing elective cardiac surgery with cardiopulmonary bypass. Patients were randomized either to RIPC or to control group. Primary endpoint was postoperative neurocognitive dysfunction 5–7 days after surgery assessed by a comprehensive test battery. Cognitive change was assumed if the preoperative to postoperative difference in 2 or more tasks assessing different cognitive domains exceeded more than one SD (1 SD criterion) or if the combined Z score was 1.96 or greater (Z score criterion).ResultsAccording to 1 SD criterion, 52% of control and 46% of RIPC patients had cognitive deterioration 5–7 days after surgery (p = 0.753). The summarized Z score showed a trend to more cognitive decline in the control group (2.16±5.30) compared to the RIPC group (1.14±4.02; p = 0.228). Three months after surgery, incidence and severity of neurocognitive dysfunction did not differ between control and RIPC. RIPC tended to decrease postoperative troponin T release at both 12 hours [0.60 (0.19–1.94) µg/L vs. 0.48 (0.07–1.84) µg/L] and 24 hours after surgery [0.36 (0.14–1.89) µg/L vs. 0.26 (0.07–0.90) µg/L].ConclusionsWe failed to demonstrate efficacy of a RIPC protocol with respect to incidence and severity of POCD and secondary outcome variables in patients undergoing a wide range of cardiac surgery. Therefore, definitive large-scale multicenter trials are needed.Trial RegistrationClinicalTrials.gov NCT00877305
We conclude that human peritubular cells are a novel model for the investigation of paracrine, including mast cell initiated, interactions in the human testis, which will allow the study of fibrotic processes underlying male idiopathic infertility.
The wall of the seminiferous tubules contains contractile smooth-muscle-like peritubular cells, thought to be important for sperm transport. Impaired spermatogenesis in men typically involves remodeling of this wall, and we now found that smooth muscle cell (SMC) markers, namely myosin heavy chain (MYH11) and smooth muscle actin (SMA) are often lost or diminished in peritubular cells of testes of men with impaired spermatogenesis. This suggests reduced contractility of the peritubular wall, which may contribute to sub- or infertility. In these cases, testicular expression of cyclooxygenase-2 (COX-2) implies formation of prostaglandins (PGs). When screening different PGs for their ability to target human testicular peritubular cells (HTPCs), only a PG metabolite, 15-deoxy-Delta(12-14)-prostaglandin-J2 (15dPGJ2), was effective. In primary cultures of HTPCs, 15dPGJ2 increased cell size in a reversible manner. Importantly, 15dPGJ2 treatment resulted in a loss of typical differentiation markers for SMCs, namely MYH11, calponin, and SMA, whereas fibroblast markers were unchanged. Collagen gel contraction assays revealed that this loss correlates with a reduced ability to contract. Experiments with an antagonist (bisphenol A diglycidyl ether) and agonist (troglitazone) for a cognate 15dPGJ2 receptor (i.e. peroxisome proliferator-activated receptor-gamma) indicated that peroxisome proliferator-activated receptor-gamma is not directly involved. Rather, the mode of action of 15dPGJ2 involves reactive oxygen species. The antioxidant N-acetylcysteine not only blocked ROS formation but also prevented the increase in cell size and the loss of contractility in HTPCs challenged with 15dPGJ2. We conclude that 15dPGJ2, via reactive oxygen species, influences SMC phenotype and contractility of human peritubular cells and possibly is involved in the development of human male sub-/infertility.
Testicular peritubular cells are myofibroblastic cells, which represent the major cellular components of the wall of the seminiferous tubules. In men their phenotypic characteristics, including possible secretory activity and regulation, are not well known, in neither normal nor pathologically altered testes. Especially in testes of men with impaired spermatogenesis, the cytoarchitecture of the tubular wall is frequently remodeled and presents fibrotic thickening, increased innervation, and infiltration by macrophages and mast cells. The latter are two sources of TNF-alpha. The purpose of our study was to explore human testicular peritubular cells and mechanisms of their regulation. To this end we primarily studied cultured human testicular peritubular cells (HTPCs), isolated from adult human testes. Having established that HTPCs express TNF-alpha receptors 1 and 2 and respond to recombinant human TNF-alpha by a rapid phosphorylation of ERK1/2, we used complementary approaches, including gene array/RT-PCR studies, Western blotting/immunocytochemistry, and ELISA techniques to study phenotypic characteristics of HTPCs and actions of TNFalpha. We found that HTPCs express the nerve growth factor gene and TNF-alpha-stimulated mRNA levels and secretion of nerve growth factor in a dose- and time-dependent manner. Similarly, monocyte chemoattractant protein-1 was identified as a product of HTPCs, which was regulated by TNF-alpha in a concentration- and time-dependent manner. TNF-alpha furthermore strongly enhanced expression and/or synthesis of other inflammatory molecules, namely IL-6 and cyclooxygenase-2. Active cyclooxygenase-2 is indicated by increased prostaglandin D2 levels. In addition, intercellular adhesion molecule-1, which was not detected at protein level in the absence of TNF-alpha, was induced upon TNF-alpha stimulation. In conclusion, these results provide novel insights into the nature of human peritubular cells, which are able to secrete potent signaling molecules and are regulated by TNF-alpha. These results also hint to an as-yet-unknown role of peritubular cells in normal human testis and involvement in the pathomechanisms associated with impaired spermatogenesis in men.
Transient episodes of ischemia in a remote organ (remote ischemic preconditioning, RIPC) bears the potential to attenuate myocardial injury, but the underlying mechanisms are only poorly understood. In the pilot experimental study presented we investigated cellular and molecular effects of RIPC in heart tissue of cardiosurgical patients with cardiopulmonary bypass (CPB) and focussed on apoptotic events, local and systemic inflammation as well as the regulation of the hypoxia induced factor-1α (HIF-1α). RIPC was induced by four 5-min cycles of transient upper limb ischemia/reperfusion using a blood-pressure cuff. Right atrial tissue and serum were obtained from patients receiving RIPC (N = 32) and control patients (N = 29) before and after CPB. RIPC patients showed reduced troponin T serum concentrations in the first 48 h after surgery (P < 0.05 vs. control) indicating cardioprotective effects of RIPC. Samples from RIPC patients that were collected before CPB contained significantly increased amounts of HIF-1α and procaspase-3 (HIF-1α: P < 0.05 vs. control, procaspase-3: P < 0.05 vs. control), whereas activities of caspases 3 and 7 were by trend reduced. Samples from RIPC patients that were taken after CPB showed an increased activity of myeloperoxidase (P < 0.05 vs. control; P < 0.05 vs. RIPC before CPB) as well as elevated tissue concentrations of the interleukin (IL)-1β (P < 0.05 vs. RIPC before CPB). Serum levels of IL-8, IL-1β and TNFα were significantly increased in RIPC patients before CPB (P < 0.05 vs. control before CPB). In summary, RIPC regulates HIF-1α levels, apoptosis and inflammation in the myocardium of cardiosurgical patients and leads to increased concentrations of circulating cytokines.
We have previously found that cyclooxygenase-2 (COX-2), a key enzyme in the biosynthesis of prostaglandins (PGs), is present in the testicular interstitial cells of infertile men, whereas it is absent in human testes with no evident morphological changes or abnormalities. To find an animal model for further investigating COX-2 and its role in testicular steroidogenesis, we screened testes from adult species ranging from mice to monkeys. By using immunohistochemical assays, we found COX-2 expression only in Leydig cells of the reproductively active (peripubertal, pubertal, and adult) seasonal breeder Syrian hamster. COX-2 expression in hamster Leydig cells was confirmed by RT-PCR. In contrast, COX-1 expression was not detected in hamster testes. Because COX-2 expression implies PG synthesis, we investigated the effect of various PGs on testosterone production and found that PGF2 alpha stood out because it significantly reduced human chorionic gonadotropin-stimulated testosterone release from isolated hamster Leydig cells in a dose-dependent manner. This mechanism involves a decreased expression of testicular steroidogenic acute regulatory protein and 17beta-hydroxysteroid dehydrogenase. Testicular concentration and content of PGF2 alpha in reproductively active hamsters as well as production of PGF2 alpha from isolated hamster Leydig cells were also determined. Moreover, PGF2 alpha receptors were localized in Leydig cells of hamsters and testicular biopsies from patients with Sertoli cell only and germ arrest syndromes. Thus, in this study, we described a COX-2-initiated pathway that via PGF2 alpha production, PGF2 alpha receptors, steroidogenic acute regulatory protein, and 17beta-hydroxysteroid dehydrogenase represents a physiological local inhibitory system of human chorionic gonadotropin-stimulated testosterone production in the Syrian hamster testes.
BackgroundRemote ischemic preconditioning (RIPC) has been suggested to protect against certain forms of organ injury after cardiac surgery. Previously, we reported the main results of RIPHeart (Remote Ischemic Preconditioning for Heart Surgery) Study, a multicenter trial randomizing 1403 cardiac surgery patients receiving either RIPC or sham‐RIPC.Methods and ResultsIn this follow‐up paper, we present 1‐year follow‐up of the composite primary end point and its individual components (all‐cause mortality, myocardial infarction, stroke and acute renal failure), in a sub‐group of patients, intraoperative myocardial dysfunction assessed by transesophageal echocardiography and the incidence of postoperative neurocognitive dysfunction 5 to 7 days and 3 months after surgery. RIPC neither showed any beneficial effect on the 1‐year composite primary end point (RIPC versus sham‐RIPC 16.4% versus 16.9%) and its individual components (all‐cause mortality [3.4% versus 2.5%], myocardial infarction [7.0% versus 9.4%], stroke [2.2% versus 3.1%], acute renal failure [7.0% versus 5.7%]) nor improved intraoperative myocardial dysfunction or incidence of postoperative neurocognitive dysfunction 5 to 7 days (67 [47.5%] versus 71 [53.8%] patients) and 3 months after surgery (17 [27.9%] versus 18 [27.7%] patients), respectively.ConclusionsSimilar to our main study, RIPC had no effect on intraoperative myocardial dysfunction, neurocognitive function and long‐term outcome in cardiac surgery patients undergoing propofol anesthesia.Clinical Trial RegistrationURL: https://www.clinicaltrials.gov. Unique identifier: NCT01067703.
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