High-protein supplementation facilitates weight training-induced bone mineralization in baseball players.

OBJECTIVES: The aim of this study was to determine whether weight training combined with high-protein intake enhances total and regional bone mineral density (BMD) in athletes. METHODS: BMD of 27 Division 1 collegiate baseball players 18 to 22 y of age (N = 13, 2 dropouts) received either 14% protein or isocaloric 44% protein supplements and were assessed by dual-energy x-ray absorptiometry before and after a 12-wk weight training program (challenging upper and lower body). RESULTS: Baseline data showed unequivocally greater humerus BMD in the dominant arm than their contralateral non-dominant arm (∼20 %) among all baseball players. Humerus BMD of the non-dominant arm was enhanced by 2.7% after weight training for both low- and high-protein groups (main effect, P = 0.008), concurrent with an unexpected small decrease in total body BMD (main effect, P = 0.014). Humerus BMD of the dominant arm with greater baseline value than the non-dominant arm was not increased unless high protein was supplemented (+2.7 %; P < 0.05). CONCLUSION: Bones with relatively higher BMD show blunt adaptation against training, which can be relieved by high-protein supplementation. Total BMD of athletes cannot be further elevated by weight training.

Effects of low-level laser therapy on M1-related cytokine expression in monocytes via histone modification.

Low-level laser therapy (LLLT) has been used in the treatment of radiotherapy-induced oral mucositis and allergic rhinitis. However, the effects of LLLT on human monocyte polarization into M1 macrophages are unknown. To evaluate the effects of LLLT on M1-related cytokine and chemokine production and elucidate the mechanism, the human monocyte cell line THP-1 was treated with different doses of LLLT. The expression of M1-related cytokines and chemokines (CCL2, CXCL10, and TNF-α) was determined by ELISA and real-time PCR. LLLT-associated histone modifications were examined by chromatin immunoprecipitation (ChIP) assays. Mitochondrial involvement in the LLLT-induced M1-related cytokine expression was evaluated by quantitative real-time PCR. Flow cytometry was used to detect the cell surface markers for monocyte polarization. The results showed that LLLT (660 nm) significantly enhanced M1-related cytokine and chemokine expression in mRNA and protein levels. Mitochondrial copy number and mRNA levels of complex I-V protein were increased by LLLT (1 J/cm(2)). Activation of M1 polarization was concomitant with histone modification at TNF-α gene locus and IP-10 gene promoter area. This study indicates that LLLT (660 nm) enhanced M1-related cytokine and chemokine expression via mitochondrial biogenesis and histone modification, which may be a potent immune-enhancing agent for the treatment of allergic diseases.

The natural flavonoid apigenin suppresses Th1- and Th2-related chemokine production by human monocyte THP-1 cells through mitogen-activated protein kinase pathways.

Dietary flavonoids have various biological functions, and there is increasing evidence that reduced prevalence and severity of allergic reactions are associated with the intake of flavonoids. Among natural flavonoids, apigenin is a potent anti-inflammatory agent. However, the mechanisms of apigenin's effect remain uncertain. Monocyte-derived chemokine (MDC) plays a pivotal role in recruiting T-helper (Th) 2 cells in the allergic inflammation process. In the late phase of allergic inflammation, the Th1 chemokine interferon-inducible protein 10 (IP-10) has also been found in elevated levels in the bronchial alveolar fluid of asthmatic children. We used human THP-1 monocyte cells, pretreated with or without apigenin, prior to lipopolysaccharide stimulation. By means of enzyme-linked immunosorbent assay, we found that apigenin inhibited production of both MDC and IP-10 by THP-1 cells and that the suppressive effect of apigenin was not reversed by the estrogen receptor antagonist ICI182780. The p65 phosphorylation of nuclear factor kappaB remained unaffected, but the phosphorylation of p38, c-Jun N-terminal kinase, and extracellular signal-regulated kinase mitogen-activated protein kinase pathways were all blocked. We found that inhibition of c-raf phosphorylation might be the target of apigenin's anti-inflammation property.