Glucagon-like peptide-1 receptor signalling reduces microvascular thrombosis, nitro-oxidative stress and platelet activation in endotoxaemic mice

BACKGROUND AND PURPOSE

Excessive inflammation in sepsis causes microvascular thrombosis and thrombocytopenia associated with organ dysfunction and high mortality. The present studies aimed to investigate whether inhibition of dipeptidyl peptidase-4 (DPP-4) and supplementation with glucagon-like peptide-1 (GLP-1) receptor agonists improved endotoxaemia-associated microvascular thrombosis via immunomodulatory effects.

EXPERIMENTAL APPROACH

Endotoxaemia was induced in C57BL/6J mice by a single injection of LPS (17.5 mg kg^-1 for survival and 10 mg kg^-1 for all other studies). For survival studies, treatment was started 6 h after LPS injection. For all other studies, drugs were injected 48 h before LPS treatment.

KEY RESULTS

Mice treated with LPS alone showed severe thrombocytopenia, microvascular thrombosis in the pulmonary circulation (fluorescence imaging), increased LDH activity, endothelial dysfunction and increased markers of inflammation in aorta and whole blood (leukocyte-dependent oxidative burst, nitrosyl-iron haemoglobin, a marker of nitrosative stress, and expression of inducible NOS). Treatment with the DPP-4 inhibitor linagliptin or the GLP-1 receptor agonist liraglutide, as well as genetic deletion of DPP-4 (DPP4^-/- mice) improved all these parameters. In GLP-1 receptor-deficient mice, both linagliptin and liraglutide lost their beneficial effects and improvement of prognosis. Incubation of platelets and cultured monocytes (containing GLP-1 receptor protein) with GLP-1 receptor agonists inhibited the monocytic oxidative burst and platelet activation, with a GLP-1 receptor-dependent elevation of cAMP levels and PKA activation.

CONCLUSIONS AND IMPLICATIONS

GLP-1 receptor activation in platelets by linagliptin and liraglutide strongly attenuated endotoxaemia-induced microvascular thrombosis and mortality by a cAMP/PKA-dependent mechanism, preventing systemic inflammation, vascular dysfunction and end organ damage.

LINKED ARTICLES

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.

Oxaliplatin and 5-FU/folinic acid (modified FOLFOX6) with or without aflibercept in first-line treatment of patients with metastatic colorectal cancer: the AFFIRM study

BACKGROUND

The combination of aflibercept with FOLFIRI has been shown to significantly prolong overall survival in patients with metastatic colorectal cancer (mCRC) after progression on oxaliplatin-based therapy. This trial evaluated the addition of aflibercept to oxaliplatin-based first-line treatment of patients with mCRC.

PATIENTS AND METHODS

Patients with mCRC were randomized to receive first-line therapy with mFOLFOX6 plus aflibercept (4 mg/kg) or mFOLFOX6 alone. The primary end point of this phase II study was the progression-free survival (PFS) rate at 12 months in each arm. The analysis of efficacy between the arms was a pre-planned secondary analysis.

RESULTS

Of 236 randomized patients, 227 and 235 patients were evaluable for the primary efficacy analysis and safety, respectively. The probabilities of being progression-free at 12 months were 25.8% [95% confidence interval (CI) 17.2-34.4] for the aflibercept/mFOLFOX6 arm and 21.2% (95% CI 12.2-30.3) for the mFOLFOX6 arm. The median PFS was 8.48 months (95% CI 7.89-9.92) for the aflibercept/mFOLFOX6 arm and 8.77 months (95% CI 7.62-9.27) for the mFOLFOX6 arm; the hazard ratio of aflibercept/mFOLFOX6 versus mFOLFOX6 was 1.00 (95% CI 0.74-1.36). The response rates were 49.1% (95% CI 39.7-58.6) and 45.9% (95% CI 36.4-55.7) for patients treated with and without aflibercept, respectively. The most frequent treatment-emergent grade 3/4 adverse events (AEs) excluding laboratory abnormalities reported for aflibercept/mFOLFOX6 versus mFOLFOX6 were neuropathy (16.8% versus 17.2%) and diarrhea (13.4% versus 5.2%). Neutropenia grade 3/4 occurred in 36.1% versus 29.3%. The most common vascular endothelial growth factor inhibition class-effect grade 3/4 AEs for aflibercept/mFOLFOX6 versus mFOLFOX6 were hypertension (35.3% versus 1.7%), proteinuria (9.2% versus 0%), deep vein thrombosis (5.9% versus 0.9%) and pulmonary embolism (5.9% versus 5.2%).

CONCLUSION

No difference in PFS rate was observed between treatment groups. Adding aflibercept to first-line mFOLFOX6 did not increase efficacy but was associated with higher toxicity.

CLINICAL TRIAL NUMBER

NCT00851084, www.clinicaltrials.gov, EudraCT 2008-004178-41.

[Factors Associated with the Use of Protective Gear among Adults during Recreational Sledging]

BACKGROUND

Recreational sledging (tobogganing) is a very popular winter sport in the Alps. Therefore, injury prevention through the usage of protective gear seems important. Therefore, the aim of this study was to evaluate factors associated with the use of protective gear among adults during recreational sledging.

METHODS

Adult recreational sledgers were interviewed during the winter seasons 2012/13 and 2013/14 at six sledging tracks in Austria on demographics, skill level, sledging frequency, risk taking behaviour, sitting alone or with another person on the sledge, previous sledging-related injuries, and use of protective gear, respectively. Interviews were conducted on all days of the week.

RESULTS

A total of 1968 adult sledgers (49.4 % females) with a mean age of 37.1 ± 14.4 years participated in this study. A (ski) helmet, sun or snow goggles, a back protector, and wrist guards were used by 42.3 %, 71.0 %, 5.9 %, 2.6 % of sledgers, respectively. Helmet use was significantly higher with increasing age and increasing skill level as well as when sitting alone compared to sitting together with another person. Females, Austrians, persons sitting alone on the sledge, a higher frequency of sledging and a higher skill level were significantly associated with an increasing use of goggles. A back protector was significantly more often worn by younger people, more risky sledgers, and persons with a previous sledging-related injury. Wrist guards were significantly more often used by persons with a previous sledging-related injury.

CONCLUSION

During recreational sledging, the factors age, sex, nationality, skill level, sitting alone compared to sitting together with another person on the sledge, sledging frequency, and injury experience were associated with the frequencies of usage of different types of protective gear. These factors should be considered when implementing preventive measures for recreational sledging.

[Equipment, Risk Awareness and Safety-Relevant Behaviour of Via Ferrata Climbers]

BACKGROUND

Climbing via ferrata routes is becoming more and more popular. The growing number of via ferrata climbers is associated with an increasing number of accidents. In addition to adequate equipment and its correct handling, knowledge of specific risks and safety-related behaviour play an important role for safety on via ferrata routes. The goal of this study was to collect data on equipment, via ferrata-specific risk knowledge, safety-related behaviour, and general risk-taking behaviour of via ferrata climbers.

METHODS

In this survey, data of 332 climbers of different via ferrata routes in Tyrol (Austria) were collected using a standardised data entry form including socio-demographic data, the use of via ferrata-specific equipment and first aid equipment. Knowledge of via ferrata-specific risks was assayed by a questionnaire including 4 questions. Additionally, safety-related behaviour and general risk-taking behaviour of the via ferrata climbers were evaluated.

RESULTS

92 % of the interviewed persons were wearing a helmet and helmet use was significantly lower in females (86 %) compared to males (96 %). In total, 10 % of the via ferrata climbers used inadequate belaying equipment or no equipment at all. The 4 questions related to via ferrata-specific risks were correctly answered by an average of 46 % of the climbers. A partner check was carried out by 76 % before starting the tour. 96 % of the climbers stated they ask the climber ahead of them for the possibility to overtake and wait for a suitable and safe spot. 64 % reported that they would not pass without self-belay. General risk-taking behaviour was scored at 4.26 ± 1.75 with significant differences between female and male via ferrata climbers (3.79 ± 1.37 vs. 4.53 ± 1.88).

CONCLUSION

Although most of the via ferrata climbers use adequate equipment, helmet use could be optimised in females. Via ferrata climbers should be better informed of the risks of climbing via ferrata routes and safety-related behaviour. Preventive measures including information panels at the entrances of the via ferrata routes and broad information campaigns could contribute to reduce the number of accidents.

[Frequencies of injuries and causes of accidents during ski touring on ski slopes - a pilot study]

INTRODUCTION

Ski touring along ski slopes (slope touring) increased in recent years on Austrian ski slopes. However, ascending on the border of the slope and skiing downhill on the slope might be associated with a certain injury risk. Thus, the aim of this pilot study was to evaluate frequencies of injuries, causes of accidents and potential risk factors during slope touring.

METHODS

Slope-tourers were interviewed from March to April 2014 at the bottom of 4 Austrian ski areas. Interviews were conducted during the week and at the weekend from 7.30 a. m. to 8.45 p. m.

RESULTS

A total of 451 slope-tourers (60.1 % males) with a mean age of 39.3 ± 14.4 years were interviewed. Interviewed persons reported that they perform about 20.6 ± 16.0 slope tours per season mainly with a partner (48 %) and during the day (51 %). Ski helmet use was 60 %. A total of 57 persons (12.6 %) reported that they suffered at least once from an injury during slope touring needing medical care. This corresponds to a rate of 6 injuries per 1000 slope tours. Main injury causes were a fall (78 %) and a collision with another person (15 %) and the main injured body part was the knee (36 %). Slope-tourers with an injury were wearing more often back protectors, and were falling more often during downhill skiing, and were abstaining less often from alcohol and were listening more often to music during downhill skiing compared to slope-tourers without an injury.

CONCLUSION

Based on the findings of this pilot study we recommend abstaining from alcohol and not listening to music during downhill skiing to reduce the injury risk during slope touring.

[The flexibility of family medicine]

We are a European academic group of family doctors and we propose a definition of flexibility in family medicine. A review of the literature shows that flexibility and complexity are emerging concepts in the field of family practice. The outcomes of a workshop at the WONCA-Europe congress in 2014 are discussed. The flexibility is a capability of the general practitioner to deal with complex clinical situations in a biomedical and societal changing world. Flexibility is framed by ethics. It could improve the quality of care, be useful against burnout and used in medical research. In conclusion, family medicine should adopt a specific definition of the flexibility describing its specificity, a useful and teachable capacity.

[Current incidence of accidents on Austrian ski slopes]

BACKGROUND

Alpine skiing and snowboarding are the most popular winter sports. These sports are also associated with a certain injury risk which, however, has steadily decreased during the past decades. During the winter season 2002/2003 the last large survey on ski injuries in Austria was performed. Among others, modern skiing equipment and optimized slope preparation may impact on the injury risk. We hypothesise that these changes may have led to a further decrease in ski injuries during the past decade.

METHODS

In the winter season 2012/2013, skiing injuries were recorded in 26 Austrian ski areas. Data were collected from rescue personnel on ski slopes and by physicians in the hospital or doctors practice with the help of a questionnaire.

RESULTS

A total of 7325 injured skiers and snowboarders (age: 34.8 ± 17.8 years) were recorded (49 % males and 51 % females; 80 % skiers, 14 % snowboarders, 6 % others). The most frequent causes of injury were self-inflicted falls (87 %) and collisions with other skiers/snowboarders (8 %). Most affected injury locations among skiers were the knee (41 %; predominantly in female skiers, > 50 %), shoulder/back (18 %) and arms (10 %). Most affected injury locations among snowboarders were arms (38 %) and shoulder/back (23 %). Head injuries were found at the same frequency (8 %) in skiers and snowboarders. The calculated injury rate was about 0.6 injuries per 1000 skier days and has decreased by more than 50 % during the past decade.

CONCLUSIONS

Modern skiing equipment and optimised slope preparation may be at least partly responsible for the decreased injury risk on ski slopes which is supported by the observation of a reduced falling frequency. Future preventive measures should focus on a reduction of knee injuries in female skiers.

Effect of wearing a ski helmet on perception and localization of sounds

Helmet use on ski slopes has steadily increased worldwide over the past years. A common reason reported for helmet non-use, however, is impaired hearing. Therefore, an intra-subject design study was conducted to compare hearing thresholds and sound source localization of 21 adults with normal hearing in an anechoic chamber when wearing a ski helmet and ski goggles or wearing a ski cap and ski goggles to the condition head bare. Hearing thresholds while wearing a ski helmet (6.8 ± 1.6 dB HL) and ski cap (5.5 ± 1.6 dB HL) were significantly different (p = 0.030, d = 0.44). Compared to head bare (2.5 ± 1.2 dB HL), a significant difference was found for the ski helmet only (p = 0.040, d = 1.57). Regarding sound source localization, correct scores in the condition head bare (90%) showed a highly significant difference compared with those of condition cap (65%) and helmet (58%), respectively (p < 0.001; d > 2.5). Compared to the ski cap, wearing the helmet significantly reduced correct scores (p = 0.020, d = 0.59) irrespective of the tested sound pressure levels. In conclusion, wearing a ski helmet impairs hearing to a small though significantly greater extent compared with a cap, the degree, however, being less than what is termed as a hearing impairment. Compared to the condition head bare, wearing a ski cap or a ski helmet significantly reduced one's ability of sound source localization.

Does listening to music with an audio ski helmet impair reaction time to peripheral stimuli?

With the recent worldwide increase in ski helmet use, new market trends are developing, including audio helmets for listening to music while skiing or snowboarding. The aim of this study was to evaluate whether listening to music with an audio ski helmet impairs reaction time to peripheral stimuli. A within-subjects design study using the Compensatory-Tracking-Test was performed on 65 subjects (36 males and 29 females) who had a mean age of 23.3 ± 3.9 years. Using repeated measures analysis of variance, we found significant differences in reaction times between the 4 test conditions (p=0.039). The lowest mean reaction time (± SE) was measured for helmet use while listening to music (507.9 ± 13.2 ms), which was not different from helmet use alone (514.6 ± 12.5 ms) (p=0.528). However, compared to helmet use while listening to music, reaction time was significantly longer for helmet and ski goggles used together (535.8 ± 14.2 ms, p=0.005), with a similar trend for helmet and ski goggles used together while listening to music (526.9 ± 13.8 ms) (p=0.094). In conclusion, listening to music with an audio ski helmet did not increase mean reaction time to peripheral stimuli in a laboratory setting.