[Show abstract][Hide abstract] ABSTRACT: The tripeptide glutathione is the most abundant cellular antioxidant with high medical relevance, and it is also required as a co-factor for various enzymes involved in the detoxification of reactive oxygen species and toxic compounds. However, its cell-type specific functions and its interaction with other cytoprotective molecules are largely unknown. Using a combination of mouse genetics, functional cell biology and pharmacology, we unraveled the function of glutathione in keratinocytes and its cross-talk with other antioxidant defense systems. Mice with keratinocyte-specific deficiency in glutamate cysteine ligase, which catalyzes the rate-limiting step in glutathione biosynthesis, showed a strong reduction in keratinocyte viability in vitro and in the skin in vivo. The cells died predominantly by apoptosis, but also showed features of ferroptosis and necroptosis. The increased cell death was associated with increased levels of reactive oxygen and nitrogen species, which caused DNA and mitochondrial damage. However, epidermal architecture, and even healing of excisional skin wounds were only mildly affected in the mutant mice. The cytoprotective transcription factor Nrf2 was strongly activated in glutathione-deficient keratinocytes, but additional loss of Nrf2 did not aggravate the phenotype, demonstrating that the cytoprotective effect of Nrf2 is glutathione dependent. However, we show that deficiency in glutathione biosynthesis is efficiently compensated in keratinocytes by the cysteine/cystine and thioredoxin systems. Therefore, our study highlights a remarkable antioxidant capacity of the epidermis that ensures skin integrity and efficient wound healing.
[Show abstract][Hide abstract] ABSTRACT: Cartilage oligomeric matrix protein (COMP) is an abundant component in the extracellular matrix (ECM) of load-bearing tissues such as tendons and cartilage. It serves adaptor functions by bridging different ECM structures. We previously showed that COMP is also a constitutive component of healthy human skin and strongly induced in fibrosis. It binds directly and with high affinity to collagen I and to collagen XII that decorates the surface of collagen I fibrils.We demonstrate here that lack of COMP-collagen interaction in the extracellular space leads to changes in collagen fibril morphology and density resulting in altered skin biomechanical properties. Surprisingly, COMP also fulfills an important intracellular function in assisting efficient secretion of collagens, which were retained in the endoplasmic reticulum of COMP-null fibroblasts. Accordingly COMP-null mice showed severely attenuated fibrotic responses in skin. Collagen secretion was fully restored by introducing wild type COMP. Hence, our work unravels a novel, non-structural and intracellular function of the ECM protein COMP in controlling collagen secretion.
Full-text · Article · Jan 2016 · Journal of Cell Science
[Show abstract][Hide abstract] ABSTRACT: Cardiovascular disease is often caused by endothelial cell (EC) dysfunction and atherosclerotic plaque formation at predilection sites. Also surgical procedures of plaque removal cause irreversible damage to the EC layer, inducing impairment of vascular function and restenosis. In the current study we have examined a potentially curative approach by radially symmetric re-endothelialization of vessels after their mechanical denudation. For this purpose a combination of nanotechnology with gene and cell therapy was applied to site-specifically re-endothelialize and restore vascular function. We have used complexes of lentiviral vectors and magnetic nanoparticles (MNPs) to overexpress the vasoprotective gene endothelial nitric oxide synthase (eNOS) in ECs. The MNP-loaded and eNOS-overexpressing cells were magnetic, and by magnetic fields they could be positioned at the vascular wall in a radially symmetric fashion even under flow conditions. We demonstrate that the treated vessels displayed enhanced eNOS expression and activity. Moreover, isometric force measurements revealed that EC replacement with eNOS-overexpressing cells restored endothelial function after vascular injury in eNOS(-/-) mice ex and in vivo. Thus, the combination of MNP-based gene and cell therapy with custom-made magnetic fields enables circumferential re-endothelialization of vessels and improvement of vascular function.
[Show abstract][Hide abstract] ABSTRACT: This study evaluates the feasibility of an exercise program for patients with severe alcohol dependence in a long-term residential setting and the ability of such a program to improve their level of physical activity and quality of life. Forty-four (44) participants were assigned to two groups, an intervention group experiencing the exercise program and a control group which did not participate in the program. Another matched control group, without the health issues of the other two groups, was also used as a basis of comparison. The study was designed as a year-long longitudinal controlled study with a pre-post design. Measures used to determine the effectiveness of the intervention were attendance records, the SF-36 questionnaire, and monitoring devices of daily activity. Active participants in the exercise program showed a significant improvement in physical activity and an enhanced quality of life.
No preview · Article · Jan 2016 · Alcoholism Treatment Quarterly
[Show abstract][Hide abstract] ABSTRACT: Sickle cell anemia (SCA) is an inherited red blood cells (RBC) disorder characterized by significantly decreased RBC deformability. The present study aimed to assess whether modulation of RBC Nitric Oxide Synthase (RBC-NOS) activation could affect RBC deformability in SCA.
Blood of twenty-five SCA patients was treated for 1 hour at 37°C with Phosphate Buffered Saline (PBS) or PBS containing 1% of Dimethylsulfoxyde as control, L-arginine or N(5)-(1-Iminoethyl)-L-ornithine (L-NIO) to directly stimulate or inhibit RBC-NOS, insulin or wortmannin to indirectly stimulate or inhibit RBC-NOS through their effects on the PI3 Kinase/Akt pathway, and sodium nitroprusside (SNP) and 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) as NO donor and NO scavenger, respectively. RBC deformability was measured by ektacytometry at 3 Pa.
RBC deformability significantly increased after insulin treatment and significantly decreased after L-NIO and wortmannin incubation. The other conditions did not affect deformability. Significantly increased nitrotyrosine levels, a marker of enhanced free radical generation, were detected by immunohistochemistry in SNP and insulin treated samples.
These data suggest that RBC deformability of SCA can be modulated by RBC-NOS activity but also that oxidative stress may impair effectiveness of RBC-NOS produced NO.
No preview · Article · Dec 2015 · Clinical hemorheology and microcirculation
[Show abstract][Hide abstract] ABSTRACT: High-intensity training (HIT) can improve endurance performance and VO2max more effectively than high-volume training (HVT). Hence, the implementation of HIT protocols such as 4x30 s "all-out" and 4x4 min at 90-95% VO2max is currently existent in various sports. However, there is limited awareness of the acute changes in blood cell count following these protocols. Therefore, the purpose of the study was to examine the acute effects on circulating leukocyte differential count (LDC) by comparing the two HIT interventions with a single HVT intervention. 12 healthy triathletes/cyclists (VO2peak: 64.3 ± 9.7 mL·kg-1·min-1) participated in the study. Subjects performed 1) a two-hours low- intensity exercise at an intensity of 55% peak power output (PPO); 2) 4x4 min interval bouts at an intensity of 90 - 95% PPO; 3) 4x30 s "all-out". Blood samples were taken immediately before exercise (pre) and 0', 30', 60' and 180' post-exercise. Biphasic leukocyte enumeration was different between both HIT protocols and nonexistent after high-volume exercise. Data revealed significant time and intervention effects for leukocytes, lymphocytes and neutrophils. After 4x30 s lymphocytes were significantly higher 0 ́ post-intervention compared to 4x4 min and high-volume exercise. Furthermore, concentrations of leukocytes and neutrophils were significantly higher after the "all-out" protocol compared to 4x4 min at 180' post-exercise. The results suggest that 4x30 s result in larger short-term perturbations in the circulating fraction of leukocytes compared to 4x4 min, which might be associated with increased hormonal and metabolic stress responses after 4x30 s.
No preview · Article · Nov 2015 · The Journal of sports medicine and physical fitness
[Show abstract][Hide abstract] ABSTRACT: The Merkel cell-neurite complex initiates the perception of touch and mediates Aβ slowly adapting type I responses. Lichen planus is a chronic inflammatory autoimmune disease with T-cell-mediated inflammation, whereas hyperkeratosis is characterized with or without epithelial dysplasia in the oral mucosa. To determine the effects of lichen planus and hyperkeratosis on the Merkel cell-neurite complex, healthy oral mucosal epithelium and lesional oral mucosal epithelium of lichen planus and hyperkeratosis patients were stained by immunohistochemistry using an avidin-biotin-peroxidase complex and double immunofluorescence using pan cytokeratin, cytokeratin 20 (K20, a Merkel cell marker), and neurofilament 200 (NF200, a myelinated Aβ- and Aδ-nerve fibre marker) antibodies. NF200-immunoreactive (ir) nerve fibres in healthy tissues and in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis were counted and statistically analysed. In the healthy oral mucosa, K20-positive Merkel cells with and without close association to the intraepithelial NF200-ir nerve fibres were detected. In the lesional oral mucosa of lichen planus and hyperkeratosis patients, extremely rare NF200-ir nerve fibres were detected only in the lamina propria. Compared with healthy tissues, lichen planus and hyperkeratosis tissues had significantly decreased numbers of NF200-ir nerve fibres in the oral mucosal epithelium. Lichen planus and hyperkeratosis were associated with the absence of Aβ-nerve endings in the oral mucosal epithelium. Thus, we conclude that mechanosensation mediated by the Merkel cell-neurite complex in the oral mucosal epithelium is impaired in lichen planus and hyperkeratosis.
No preview · Article · Oct 2015 · International Journal of Oral Science
[Show abstract][Hide abstract] ABSTRACT: Activation of the immune response during injury is a critical early event that determines whether the outcome of tissue restoration is regeneration or replacement of the damaged tissue with a scar. The mechanisms by which immune signals control these fundamentally different regenerative pathways are largely unknown. We have demonstrated that, during skin repair in mice, interleukin-4 receptor α (IL-4Rα)-dependent macrophage activation controlled collagen fibril assembly and that this process was important for effective repair while having adverse pro-fibrotic effects. We identified Relm-α as one important player in the pathway from IL-4Rα signaling in macrophages to the induction of lysyl hydroxylase 2 (LH2), an enzyme that directs persistent pro-fibrotic collagen cross-links, in fibroblasts. Notably, Relm-β induced LH2 in human fibroblasts, and expression of both factors was increased in lipodermatosclerosis, a condition of excessive human skin fibrosis. Collectively, our findings provide mechanistic insights into the link between type 2 immunity and initiation of pro-fibrotic pathways.
[Show abstract][Hide abstract] ABSTRACT: This study examines the effects of endurance training on red blood cells (RBC) in seventeen non-insulin-dependent type 2 diabetic men with a special focus on in vivo RBC aging. Venous blood was collected pre- and post-training at rest. RBC from whole blood and RBC separated according to cell age by density-gradient centrifugation were analyzed. RBC deformability was measured by ektacytometry. Immunohistochemical staining was performed to quantify the RBC-nitric oxide (NO) synthase activation (RBC-NOSSer1177) because RBC-NOS-produced NO can contribute to increased RBC deformability. The proportion of "young" RBC was significantly higher post-training. RBC deformability of all RBC (RBC of all ages) remained unaltered post-training. During RBC aging, RBC deformability decreased in both pre- and post-training. However, the training significantly increased RBC deformability in "young" and reduced their deformability in aging RBC. RBC-NOS activation remained unaltered in all RBC post-training. It tendentially increased in aging RBC pre-training, but did not change during aging post-training. The training significantly reduced RBC-NOS activation in "old" RBC. Endurance training may improve the RBC system (higher amount of "young" RBC which are more deformable). It remains speculative whether changes in older RBC (reduced RBC-NOS activation and deformability) could lead to more rapid elimination of aged RBC.
No preview · Article · Sep 2015 · Clinical hemorheology and microcirculation
[Show abstract][Hide abstract] ABSTRACT: Oncological treatments can lead to acute and chronic cancer related toxicities. In recent years, a large number of clinical studies have reported positive effects of exercise to the bio-psycho-social regeneration of cancer patients. However, very few evidence-based programs have been implemented into practice with little opportunity for cancer patients to engage in such programs. Reviews and RCT studies on exercise and cancer are showing that specific exercise programs have a positive impact on fatigue syndrome, urinary incontinence, lymphedema, polyneuropathy, arthralgia, and androgen deprivation related toxicities. With the increasing evidence for exercise oncology interventions, recommendations arising from clinical trials should be translated into clinical practice and this should be viewed as an important next step in this fast moving field of exercise oncology. For that the personalized treatment concept "Oncologic clinical exercise" (OTT) was developed.
No preview · Article · Sep 2015 · DMW - Deutsche Medizinische Wochenschrift
[Show abstract][Hide abstract] ABSTRACT: Victims that were exposed to the chemical warfare agent Sulfur mustard (SM) suffer from chronic dermal and ocular lesions, severe pulmonary problems and cancer development. It has been proposed that epigenetic perturbations might be involved in that process but this has not been investigated so far. In this study, we investigated epigenetic modulations in vitro using early endothelial cells (EEC) that were exposed to different SM concentrations (0.5, 1.0, 23.5 and 50μM). A comprehensive analysis of 78 genes related to epigenetic pathways (i.e. DNA-methylation and post-translational histone modifications) was performed. Moreover, we analyzed global DNA methylation in vitro in EEC after SM exposure as a maker for epigenetic modulations and in vivo using human skin samples that were obtained from a patient 1 year after an accidently exposure to pure SM. SM exposure resulted in a complex regulation pattern of epigenetic modulators which was accompanied by a global increase of DNA methylation in vitro. Examination of the SM exposed human skin samples also revealed a significant increase of global DNA methylation in vivo, underlining the biological relevance of our findings. Thus, we demonstrated for the first time that SM affects epigenetic pathways and causes epigenetic modulations both in vivo and in vitro.
No preview · Article · Sep 2015 · Toxicology Letters
[Show abstract][Hide abstract] ABSTRACT: Einleitung / Problemstellung: Die extrakorporale Stoßwellenbehandlung wird bei unterschiedlichen Erkrankungen und zur Regeneration verschiedener Gewebe eingesetzt. So zeigten sich bei Nierensteinen, Osteoarthritis, erektiler Dysfunktion und Verletzungen des Bewegungsapparates positive Ergebnisse, deren Ursachen bisher nur unzureichend geklärt sind. Um das adaptive Potential von Stoßwellen durch muskuläre Schädigung zu untersuchen, wurde in der vorliegenden Pilotstudie der Einfluss auf die Serumkonzentration der Creatinkinase (CK) und Laktatdehydrogenase (LDH) untersucht.
Methodik: Vier gesunde, unverletzte, männliche Probanden zwischen 18 und 35 Jahren wurden einmalig mit fokussierten Stoßwellen behandelt, die auf dem M. quadriceps femoris appliziert wurden. Venöse Blutabnahmen erfolgten unmittelbar vor (Pre) und nach der Behandlung (Post), sowie 2, 6 und 24 Stunden im Anschluss. Die CK- und LDH-Konzentrationen wurden mittels antikörperbasierter Nachweisverfahren (ELISA) bestimmt, deren Veränderungen anschließend über Effektstärken (Cohen’s d) zum Ausgangswert verdeutlicht wurden.
Ergebnisse: Die maximale CK-Konzentration lag bei 211 U∙l-1, was auf eine minimale Muskelschädigung hinweist. Zum Post-Wert ergab sich zunächst eine geringe bis mittlere Abnahme (dPost = -0,42), die sich durch den Anstieg bei 2 (d2h = 0,22) und 6h (d6h = 0,40) relativierte. Nach 24h wurde nahezu das Ausgangsniveau erreicht (d24h = -0,08). Während die CK-Werte nahezu konstant blieben, verlief die LDH inter-individuell sehr unterschiedlich. Trotz der höheren Effektstärken (dPost = -0,31; d2h = 0,42; d6h = 1,11; d24h = -0,48) lag die Differenz zwischen Pre und 24h lediglich bei 2,75 U∙l-1.
Diskussion / Schlussfolgerungen: Anhand der Ergebnisse lässt sich vermuten, dass die einmalige Stoßwellenapplikation keinen bedeutsamen, mechanischen Stimulus für etwaige Adaptationen hervorruft. Allerdings können durch die geringe Fallzahl (n = 4) und die inter-individuelle Variabilität der Verläufe keine hinreichenden Aussagen getroffen werden. Weitere Studien mit einem größeren Stichprobenumfang und längerem Messzeitraum, erscheinen für die Untersuchung muskulärer Schädigungen durch Stoßwellen ratsam.
[Show abstract][Hide abstract] ABSTRACT: Filipovic, A, Kleinöder, H, Plück, D, Hollmann, W, Bloch, W, and Grau, M. Influence of whole-body electrostimulation on human red blood cell deformability. J Strength Cond Res 29(9): 2570-2578, 2015-Red blood cell-nitric oxide synthase (RBC-NOS)-dependent NO production is essential for the maintenance of RBC deformability, which is known to improve oxygen supply to the working tissue. Electrostimulation of the whole body (WB-EMS) has been shown to improve maximal strength, springiness, and jumping power of trained and untrained athletes. To examine whether these 2 parameters are associated, this study, for the first time, aimed to investigate the effects of an 18-week dynamic WB-EMS program on RBC deformability in addition to maximal strength performance (1 repetition maximum [1RM]) in elite soccer players. Fifteen test persons were assigned in either WB-EMS group (EG, n = 10) or training group (TG, n = 5). Next to their weekly training sessions, EG performed 3 × 10 squat jumps under the influence of WB-EMS twice per week between weeks 1 and 14 and once per week between weeks 14 and 18. Training group only performed 3 × 10 squat jumps. Performance was assessed by a maximal strength test on the leg press machine (1RM). Subjects were tested at baseline and after weeks 7, 14, and 18 with blood sampling before (Pre), 15-30 minutes after (Post), and 24 hours after (24-hour Post) the training. The results showed that maximal strength was significantly improved in EG (p < 0.01). Maximum RBC deformability (EImax) increased on EMS stimulus in EG while it remained unaffected in the TG. Acute increase in EImax at baseline was explained by an increase in RBC-NOS activation while chronic increase of deformability must be caused by different, yet unknown, mechanisms. EImax decreased between weeks 14 and 18 suggesting that 1 WB-EMS session per week is not sufficient to alter deformability (EImax). In contrast, the deformability at low shear stress (EI 3 Pa), comparable with conditions found in the microcirculation, significantly increased in EG until week 14, whereas in TG deformability only, increased until week 7 due to increasing training volume after the winter break. The results indicate that WB-EMS represents a useful and time-saving addition to conventional training sessions to improve RBC deformability and possibly oxygen supply to the working tissue and thus promoting general force components in high performance sport.
Full-text · Article · Sep 2015 · The Journal of Strength and Conditioning Research
[Show abstract][Hide abstract] ABSTRACT: Objective: To provide initial information on the prevalence of physical activity levels in prostate cancer patients with bone metastases and identify associations with physical and mental health outcomes.
Methods: Self-reported physical activity levels (Modified Godin Leisure-Time Exercise Questionnaire), physical and mental health outcomes (SF-36 Questionnaire), as well as objective physical performance measures (400m walk, 6m walk) were assessed in 48 prostate cancer survivors (mean age 70.7 ± 8.0; BMI 28.5 ± 4.2; PSA 52.7 ± 154.1) with bone metastases (58.8% > 2 regions affected) at baseline of a randomised controlled trial.
Results: Only 14 men (29.2%) met the current aerobic exercise guidelines (150 minutes of moderate intensity or 75 minutes of vigorous exercise per week or an equivalent combination), while 34 (70.8%) were insufficiently active. Men that were not meeting the aerobic exercise guidelines, had lower physical functioning (p<.01), role functioning (physical and emotional) (p<.05), and general health scores (p<.05). The 6m walk (fast pace) and 400m walk times were also slower, indicating reduced physical performance in men who were insufficiently active compared to those meeting aerobic exercise guidelines (p<.05).
Conclusions: Lower levels of aerobic exercise are associated with reduced physical and mental health outcomes in prostate cancer survivors with bone metastases. While previous research has focused primarily on non-metastatic cancer patients, our initial results suggest that meeting aerobic exercise guidelines may preserve health outcomes in prostate cancer patients with advanced bone metastatic disease. Further research is required to confirm and expand these findings.
No preview · Article · Aug 2015 · BJU International
[Show abstract][Hide abstract] ABSTRACT: Herpes simplex virus type 1 (HSV-1) invades its human host via skin or mucosa. We aim to understand how HSV-1 overcomes the barrier function of the host epithelia, and for this reason established an ex vivo infection assay initially with murine skin samples. Here, we report how tissue has to be prepared to be susceptible to HSV-1 infection. Most efficient infection of the epidermis was achieved by removing the dermis. HSV-1 initially invaded the basal epidermal layer and from there spreading to the suprabasal layers was observed. Strikingly, in resting stage hair follicles, only the hair germ was infected, whereas the quiescent bulge stem cells (SC) were resistant to infection. However, during the growth phase, infected cells were also detected in the activated bulge SC. We demonstrated that cell proliferation was not a precondition for HSV-1 invasion but SC activation was required as shown by infection of aberrantly activated bulge SC in integrin-linked kinase (ILK)-deficient hair follicles. These results suggest that the status of the bulge SC determines whether HSV-1 can reach its receptors, while the receptors on basal keratinocytes are accessible irrespective of their proliferation status.Journal of Investigative Dermatology accepted article preview online, 23 July 2015. doi:10.1038/jid.2015.290.