Frank-Christoph Mooren

Physical activity and memory functions: An interventional study

Previous studies have suggested beneficial effects of physical activity on cognition. Here, we asked in an interventional approach if physical activity performed at different intensity levels would differentially affect episodic memory function. Additionally, we tried to identify mechanisms mediating these changes. Sixty-two healthy elderly individuals were assessed for level of physical activity, aerobic fitness, episodic memory score, neurotrophin and catecholamine levels, and received a magnetic resonance image of the brain at baseline and after a six months intervention of medium or low-intensity physical activity or control. Increase in total physical activity was positively associated with increase in memory score over the entire cohort, without significant differences between intensity groups. It was also positively associated with increases in local gray matter volume in prefrontal and cingulate cortex, and BDNF levels (trend). In conclusion, we showed that physical activity conveys the beneficial effects on memory function independently of its intensity, possibly mediated by local gray matter volume and neurotrophic factors. Our findings may carry significant implications for prevention of cognitive decline in the elderly.

Physical activity and memory functions: are neurotrophins and cerebral gray matter volume the missing link?

Epidemiological studies reveal better cognitive function in physically active individuals. Possible mediators for this effect are neurotrophins, which are up-regulated through physical exercise and induce neuronal growth and synaptogenesis in the animal model. Here we cross-sectionally assessed 75 healthy older individuals for levels of physical activity, aerobic fitness, and memory encoding, as well as neurotrophin levels and cerebral gray matter volume. We found that physical activity, but not cardiovascular fitness, was associated with better memory encoding after controlling for age, sex, education, depression, alcohol consumption, and smoking. Higher levels of physical activity were associated with higher levels of the neurotrophin granulocyte colony stimulating factor (G-CSF) and increased cerebral gray matter volume in prefrontal and cingulate cortex as assessed by magnetic resonance voxel-based morphometry. While mediating factors will need to be further elucidated, these findings indicate that even low-level physical activity exerts beneficial effects on memory functions in older individuals.

Oral magnesium supplementation reduces insulin resistance in non‐diabetic subjects – a double‐blind, placebo‐controlled, randomized trial

The incidence of insulin resistance and metabolic syndrome correlates with the availability of magnesium (Mg). We studied the effect of oral Mg supplementation on insulin sensitivity and other characteristics of the metabolic syndrome in normomagnesemic, overweight, insulin resistant, non‐diabetic subjects. Subjects were tested for eligibility using oral glucose tolerance test (OGTT) and subsequently randomized to receive either Mg–aspartate–hydrochloride (n = 27) or placebo (n = 25) for 6 months. As trial endpoints, several indices of insulin sensitivity, plasma glucose, serum insulin, blood pressure and lipid profile were determined. Mg supplementation resulted in a significant improvement of fasting plasma glucose and some insulin sensitivity indices (ISIs) compared to placebo. Blood pressure and lipid profile did not show significant changes. The results provide significant evidence that oral Mg supplementation improves insulin sensitivity even in normomagnesemic, overweight, non‐diabetic subjects emphasizing the need for an early optimization of Mg status to prevent insulin resistance and subsequently type 2 diabetes.

Participation in sports and physical activity of haemophilia patients

Summary.  Modern therapy options offer haemophiliacs more and more possibilities for an active participation in sports. The purpose of the present study was to investigate the attitude of these patients towards sports, their participation in school and leisure time sports activities, and differences between juveniles and adults. We investigated 44 children and adolescents (aged from 4 to 16 years) and 27 adults (aged from 18 to 72 years) with haemophilia by means of a questionnaire. 79.6% of the juvenile patients participated always or almost always in school sports, while this percentage was significantly (P < 0.05) lower in the former school time of the adults (37%). Sports play an important or very important role in leisure time activities for 75% of the adolescent and 55.5% of the adult haemophiliacs (P < 0.05). Bleeding complications occurred in 17.6% of all patients; there was no correlation with any particular type of sports. There were only slight differences between both groups, regarding their motivation to participate in sports activities. The main reasons involved social aspects and having fun. The results show that the modern therapy of haemophilia probably leads to a more positive attitude towards sports and to a wider spectrum of practised sports. This, however, may be associated with an increasing potential of health risks, which require a high level of sports medical care.

Regular endurance exercise improves the diminished hepatic carnitine status in mice fed a high-fat diet

SCOPE Metabolic stress induced by chronic high-fat (HF) diet feeding or genetically induced diabetes impairs carnitine status. Herein, we tested the hypothesis that regular endurance exercise (EE) improves the HF diet-induced impairment of carnitine status through stimulating the expression of hepatic genes involved in carnitine synthesis and uptake. METHODS AND RESULTS Eighteen male C57BL/6 mice were assigned to three groups: group S received a standard diet, group HF received a HF diet, and group HF+EE received an HF diet and was regularly exercised on a treadmill. After 10 wk, mice of the HF and the HF+EE groups were highly obese and insulin resistant compared with mice of the S group (p<0.05), but mice of the HF+EE group were less insulin resistant than those of the HF group (p<0.05). The HF group had lower carnitine concentrations and mRNA and protein levels of genes involved in carnitine synthesis and uptake in the liver than the S group (p<0.05), whereas these parameters did not differ between the S group and the HF+EE group. CONCLUSION These findings indicate that regular EE reverses an HF diet-induced impairment of hepatic carnitine content by stimulating hepatic carnitine synthesis and uptake.

Supplementing Obese Zucker Rats with Niacin Induces the Transition of Glycolytic to Oxidative Skeletal Muscle Fibers

In the present study, we tested the hypothesis that niacin increases the oxidative capacity of muscle by increasing the oxidative type I muscle fiber content. Twenty-four obese Zucker rats were assigned to 2 groups of 12 rats that were fed either a control diet (O group) or a diet supplemented with 750 mg/kg diet niacin (O+N group) for 4 wk. In addition, one group of lean rats (L group) was included in the experiment and fed the control diet for 4 wk. Plasma and liver concentrations of TG were markedly greater in obese groups than in the L group but markedly lower in the O+N group than in the O group (P < 0.05). Rats of the O+N group had a higher percentage of oxidative type I fibers and higher mRNA levels of genes encoding regulators of muscle fiber composition (Ppard, Ppargc1a, Ppargc1b), angiogenic factors (Vegfa, Vegfb), and genes involved in fatty acid utilization (Cpt1b, Slc25a20, Slc22a4, Slc22a5, Slc27a1) and oxidative phosphorylation (Cox4i1, Cox6a2) and a higher activity of the mitochondrial oxidative enzyme succinate dehydrogenase in muscle than rats of the O and L groups (P < 0.05). These niacin-induced changes in muscle metabolic phenotype are indicative of an increased capacity of muscle for oxidative utilization of fatty acids and are likely mediated by the upregulation of Ppard, Ppargc1a, and Ppargc1b, which are key regulators of muscle fiber composition, mitochondrial biogenesis, angiogenesis, and genes involved in fatty acid catabolism and oxidative phosphorylation. The increased utilization of fatty acids by muscle might contribute to the strong TG-lowering effect of niacin treatment.

Progenitor cell mobilization after exercise is related to systemic levels of G‐CSF and muscle damage

Different types of exercise are characterized by the ability to induce specific physiological stimuli that might be able to induce the mobilization of progenitor cells. The aim of the current study was to investigate the mobilization of hematopoietic progenitor cells (HPCs) and endothelial progenitor cells (EPCs) in response to endurance, resistance, and eccentric endurance exercise and their relation to markers of muscle damage and inflammation. Healthy male subjects performed acute bouts of either endurance exercise, resistance exercise, or eccentric endurance exercise. Numbers of progenitor cells and several markers of muscle damage and inflammation were determined. Although the endurance exercise was followed by an immediate and short increase of both HPCs and EPCs, the eccentric exercise evoked a long lasting increase up to 24 h for HPCs and 48 h for EPCs (P < 0.05). After resistance exercise, an increase of HPCs was only found 3 h after exercise (P < 0.05). A correlation was found between mobilized progenitor cells and systemic levels of granulocyte colony‐stimulating factor (G‐CSF) levels (r = 0.54 and r = 0.51, P < 0.05) as well as for HPCs and creatine kinase levels (r = 0.57, P < 0.05). These results suggest that mobilization of progenitor cells is related to the type of exercise and possibly mediated by G‐CSF and muscle damage.

The Immunomodulatory Effects of Physical Activity

BACKGROUND An individuals level of physical activity is one of a set of lifestyle and 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 show 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. These observations have been attributed to differential exercise-induced changes of a series of humoral and cellular immune system parameters. Furthermore, regular exercise training is a countermeasure against a persistent systemic inflammatory state which is a typical feature of cardiovascular and metabolic diseases is by lowering 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 effects of physical activity on the immune system strongly depend 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 major chronic diseases.

Effects of Traumeel (Tr14) on Exercise-Induced Muscle Damage Response in Healthy Subjects: A Double-Blind RCT

The present double-blind, randomized, placebo-controlled clinical trial intended to test whether ingestion of a natural combination medicine (Tr14 tablets) affects serum muscle damage and inflammatory immune response after downhill running. 96 male subjects received Tr14 tablets, which consist of 14 diluted biological and mineral components, or a placebo for 72 h after the exercise test, respectively. Changes in postexercise levels of various serum muscle damage and immunological markers were investigated. The area under the curve with respect to the increase (AUCi) of perceived pain score and creatine kinase (CK) were defined as primary outcome measures. While for CK the p value of the difference between the two groups is borderline, the pain score and muscle strength were not statistically significant. However, a trend towards lower levels of muscle damage (CK, p = 0.05; LDH, p = 0.06) in the Tr14 group was shown. Less pronounced lymphopenia (p = 0.02), a trend towards a lower expression of CD69 count (p = 0.07), and antigen-stimulated ICAM-1 (p = 0.01) were found in the verum group. The Tr14 group showed a tendentially lower increase of neutrophils (p = 0.10), BDNF (p = 0.03), stem cell factor (p = 0.09), and GM-CSF (p = 0.09) to higher levels. The results of the current study indicate that Tr14 seems to limit exercise-induced muscle damage most likely via attenuation of both innate and adaptive immune responses. This study was registered with ClinicalTrials.gov (NCT01912469).

Endurance and Resistance Training Affect High Fat Diet-Induced Increase of Ceramides, Inflammasome Expression, and Systemic Inflammation in Mice

The study aimed to investigate the effects of differentiated exercise regimes on high fat-induced metabolic and inflammatory pathways. Mice were fed a standard diet (ST) or a high fat diet (HFD) and subjected to regular endurance training (ET) or resistance training (RT). After 10 weeks body weight, glucose tolerance, fatty acids (FAs), circulating ceramides, cytokines, and immunological mediators were determined. The HFD induced a significant increase in body weight and a disturbed glucose tolerance (p < 0.05). An increase of plasma FA, ceramides, and inflammatory mediators in adipose tissue and serum was found (p < 0.05). Both endurance and resistance training decreased body weight (p < 0.05) and reduced serum ceramides (p < 0.005). While RT attenuated the increase of NLRP-3 (RT) expression in adipose tissue, ET was effective in reducing TNF-α and IL-18 expression. Furthermore, ET reduced levels of MIP-1γ, while RT decreased levels of IL-18, MIP-1γ, Timp-1, and CD40 in serum (p < 0.001), respectively. Although both exercise regimes improved glucose tolerance (p < 0.001), ET was more effective than RT. These results suggest that exercise improves HFD-induced complications possibly through a reduction of ceramides, the reduction of inflammasome activation in adipose tissues, and a systemic downregulation of inflammatory cytokines.