Karsten Krüger

Prof. Karsten Krüger


Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 February 2022 in Nutrients
Verified
Journal Article
Open access
PDF file
CWChristopher Weyh
Christopher Weyh
KKKarsten Krüger
Karsten Krüger
PPPeter Peeling
Peter Peeling
LCLindy M. Castell
Lindy M. Castell
Minerals fulfil a wide variety of functions in the optimal functioning of the immune system. This review reports on the minerals that are essential for the immune system’s function and inflammation regulation. We also discuss nutritional aspects of optimized mineral supply. The supply of minerals is important for the optimal function of the innate immune system as well as for components of adaptive immune defense; this involves defense mechanisms against pathogens in addition to the long-term balance of pro- and anti-inflammatory regulation. Generally, a balanced diet is sufficient to supply the required balance of minerals to help support the immune system. Although a mineral deficiency is rare, there are nevertheless at-risk groups who should pay attention to ensure they are receiving a sufficient supply of minerals such as magnesium, zinc, copper, iron, and selenium. A deficiency in any of these minerals could temporarily reduce immune competence, or even disrupt systemic inflammation regulation in the long term. Therefore, knowledge of the mechanisms and supply of these minerals is important. In exceptional cases, a deficiency should be compensated by supplementation; however, supplement over-consumption may be negative to the immune system, and should be avoided. Accordingly, any supplementation should be medically clarified and should only be administered in prescribed concentrations.

10 September 2020 in Sports Medicine - Open
Verified
Journal Article
Open access
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PWPaulina Wasserfurth
Paulina Wasserfurth
JPJana Palmowski
Jana Palmowski
Andreas HahnAndreas Hahn
Andreas Hahn
KKKarsten Krüger
Karsten Krüger
Low energy availability (LEA) represents a state in which the body does not have enough energy left to support all physiological functions needed to maintain optimal health. When compared to the normal population, athletes are particularly at risk to experience LEA and the reasons for this are manifold. LEA may result from altered dietary behaviours that are caused by body dissatisfaction, the belief that a lower body weight will result in greater performance, or social pressure to look a certain way. Pressure can also be experienced from the coach, teammates, and in this day and age through social media platforms. While LEA has been extensively described in females and female athletes have started fighting against the pressure to be thin using their social media platforms, evidence shows that male athletes are at risk as well. Besides those obvious reasons for LEA, athletes engaging in sports with high energy expenditure (e.g. rowing or cycling) can unintentionally experience LEA; particularly, when the athletes’ caloric intake is not matched with exercise intensity. Whether unintentional or not, LEA may have detrimental consequences on health and performance, because both short-term and long-term LEA induces a variety of maladaptations such as endocrine alterations, suppression of the reproductive axis, mental disorders, thyroid suppression, and altered metabolic responses. Therefore, the aim of this review is to increase the understanding of LEA, including the role of an athlete’s social environment and the performance effects related to LEA.

28 February 2020 in Nutrients
Verified
Journal Article
Open access
PDF file
CWChristopher Weyh
Christopher Weyh
KKKarsten Krüger
Karsten Krüger
BSBarbara Strasser
Barbara Strasser
With increasing age, the immune system undergoes a remodeling process, termed immunosenescence, which is accompanied by considerable shifts in leukocyte subpopulations and a decline in various immune cell functions. Clinically, immunosenescence is characterized by increased susceptibility to infections, a more frequent reactivation of latent viruses, decreased vaccine efficacy, and an increased prevalence of autoimmunity and cancer. Physiologically, the immune system has some adaptive strategies to cope with aging, while in some settings, maladaptive responses aggravate the speed of aging and morbidity. While a lack of physical activity, decreased muscle mass, and poor nutritional status facilitate immunosenescence and inflammaging, lifestyle factors such as exercise and dietary habits affect immune aging positively. This review will discuss the relevance and mechanisms of immunoprotection through physical activity and specific exercise interventions. In the second part, we will focus on the effect of dietary interventions through the supplementation of the essential amino acid tryptophan, n-3 polyunsaturated fatty acids, and probiotics (with a special focus on the kynurenine pathway).

15 June 2021 in Nutrients
Verified
Journal Article
Open access
PDF file
BSBarbara Strasser
Barbara Strasser
MWMaike Wolters
Maike Wolters
CWChristopher Weyh
Christopher Weyh
KKKarsten Krüger
Karsten Krüger
ATAndrea Ticinesi
Andrea Ticinesi
Living longer is associated with an increased risk of chronic diseases, including impairments of the musculoskeletal and immune system as well as metabolic disorders and certain cancers, each of which can negatively affect the relationship between host and microbiota up to the occurrence of dysbiosis. On the other hand, lifestyle factors, including regular physical exercise and a healthy diet, can affect skeletal muscle and immune aging positively at all ages. Accordingly, health benefits could partly depend on the effect of such interventions that influence the biodiversity and functionality of intestinal microbiota. In the present review, we first discuss the physiological effects of aging on the gut microbiota, immune system, and skeletal muscle. Secondly, we describe human epidemiological evidence about the associations between physical activity and fitness and the gut microbiota composition in older adults. The third part highlights the relevance and restorative mechanisms of immune protection through physical activity and specific exercise interventions during aging. Fourth, we present important research findings on the effects of exercise and protein as well as other nutrients on skeletal muscle performance in older adults. Finally, we provide nutritional recommendations to prevent malnutrition and support healthy active aging with a focus on gut microbiota. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low muscle mass and a higher demand for specific nutrients (e.g., dietary fiber, polyphenols and polyunsaturated fatty acids) that can modify the composition, diversity, and metabolic capacity of the gut microbiota, and may thus provide a practical means of enhancing gut and systemic immune function.

1 September 2005 in Radiology
Verified
Journal Article
Closed access
KKKarsten Krüger
Karsten Krüger
MZMarkus Zaehringer
Markus Zaehringer
DSDavid Strohe
David Strohe
HSHartmut Stuetzer
Hartmut Stuetzer
JBJulia Boecker
Julia Boecker
KLKlaus Lackner
Klaus Lackner
To prospectively evaluate ultrasonographically (US) guided percutaneous thrombin injection for treatment of femoral artery and brachial artery pseudoaneurysms. The university institutional review board approved the study. Informed consent was obtained from all patients. Two hundred forty patients with postcatheterization femoral artery (n = 132) or brachial artery (n = 8) pseudoaneurysms were treated with US-guided bovine thrombin (1.000 IU/mL) injection. At diagnosis, 107 (44.6%) patients received anticoagulation therapy; 159 (66.2%), antiplatelet therapy; and 76 (31.7%), both therapies. Pseudoaneurysm size, length and width of pseudoaneurysm neck, thrombin dose, therapy outcome, and complications were documented. The peak blood flow in peripheral arteries was determined before and after thrombin injection. Follow-up duplex US was performed 12-24 hours, 5-7 days, and 21-25 days after treatment. A nonpaired t test was used to compare differences in age between the male and female patients. Two-way analysis of covariance was performed to analyze the influences of factors that may have been related to the amount of thrombin used. Mean pseudoaneurysm volume was 4.69 cm3 +/- 5.49 (standard deviation). Simple and complex pseudoaneurysms were treated in 165 and 75 patients, respectively. A total of 260 thrombin injections were performed: 1.04 injections per patient with a simple pseudoaneurysm and 1.17 injections per patient with a complex pseudoaneurysm. The mean injected thrombin dose was 425.31 IU +/- 341.75 for all pseudoaneurysms, 382.12 IU +/- 281.00 for simple pseudoaneurysms only, and 520.33 IU +/- 434.64 for complex pseudoaneurysms only. There was only a computational correlation between pseudoaneurysm size and thrombin dose (r2 = 0.07). The primary success rate was 93.8% overall, 95.8% for simple pseudoaneurysms, and 89% for complex pseudoaneurysms. The secondary success rate was 99.6% overall, 100% for simple pseudoaneurysms, and 99% for complex pseudoaneurysms. Early (at < or =24 hours) reperfusion occurred in one simple and five complex pseudoaneurysms. Four late reperfusions-two in simple and two in complex pseudoaneurysms-were detected at 1-week follow-up; no late reperfusions were detected at 3 weeks. Thromboembolic complications occurred in two patients and resolved spontaneously. One mild allergic reaction and no infections occurred. US-guided percutaneous thrombin injection enables successful, safe management of postcatheterization pseudoaneurysms.

15 June 2016 in Current Pharmaceutical Design
Verified
Journal Article
Closed access
KKKarsten Krüger
Karsten Krüger
FMFrank-Christoph Mooren
Frank-Christoph Mooren
CPChristian Pilat
Christian Pilat
Background: An individual's level of physical activity is one of a set of lifestyle or behavioral factors that can affect immune function and health. Methods: The purpose of this review is to summarize the current knowledge in this research field and to review the recent developments in exercise immunology. Results: Most studies showed that regular exercise training increases immune competence and reduces the risk of infection compared to a sedentary lifestyle. In contrast, acute prolonged bouts of exercise and periods of intensified training are followed by a temporary increase in the risk of infection. This differential regulation can also be found in changes of several humoral and cellular immune parameters. In patients with persistent systemic inflammation, a typical feature of cardiovascular and metabolic diseases, regular exercise training lowers levels of pro-inflammatory cytokines. It is supposed that these effects are mediated by a modification of metabolic signals and innate immune regulation, the release of anti-inflammatory cytokines from muscle, the release of stress hormones, and a process known as browning of adipose tissue. Conclusion: The effect of physical activity on the immune system depends strongly on the mode and intensity of exercise or training. Thereby, considerable knowledge has accumulated concerning the significance of exercise as an important lifestyle factor for prevention and therapy of several chronic diseases.