Serum Adiponectin and Leptin Is Not Related to Skeletal Muscle Morphology and Function in Young Women.

Adipokines secreted from adipose tissue, such as adiponectin and leptin, enhance skeletal muscle metabolism. Animal studies have shown that adipokine knockout leads to a reduction in muscle function. Muscle function is determined by muscle size and quality; therefore, it is speculated that lower adipokine levels affect skeletal muscle size and quality, eventually leading to lower muscle function. This study aimed to investigate the relationship between adipokines and skeletal muscle morphology and function in young individuals. A total of 21 young women participated in this study. Adiponectin and leptin levels were analyzed using fasting blood samples from all participants. B-mode ultrasound images of the thigh and calf were obtained, and the muscle thickness and echo intensity were measured in the vastus lateralis (VL) and medial gastrocnemius (MG). The shear modulus was measured from the VL and MG using shear wave elastography. Knee extension and plantar flexion peak torques were measured as muscle functions. Adiponectin and leptin were not related to echo intensity, shear modulus, and muscle thickness in the VL and MG (rs = -0.26-0.37, P > .05). Furthermore, no relationship was observed between adiponectin, leptin, knee extension, and dorsiflexion peak torque (rs = -0.28-0.41, P > .05). These negative results suggest that adiponectin and leptin levels in young women are not associated with muscle size and quality, nor are they related to muscle function.

The Influence of Daily Exercise on Muscle Echo Intensity and Stiffness in Young Women.

This study aimed to investigate the effect of daily exercise on skeletal muscle function, size, and quality in young women. Twenty-six young women participated in this study, categorized into daily exercise and non-exercise groups. The exercise group had performed exercise or training three times a week for more than six months. Knee extension and flexion, plantar flexion, and dorsiflexion peak torques were measured for muscle function. B-mode ultrasound images were taken from the thigh and calf, and muscle thickness and echo intensity were measured in the vastus lateralis and medial gastrocnemius. Shear modulus at different joint angles of the knee (0° [full extended], 40°, and 90°) and ankle (40 °plantarflexion, 0° [neutral], and 10° dorsiflexion) was measured from the vastus lateralis and medial gastrocnemius to determine muscle stiffness. Peak torque and echo intensity did not significantly differ between the exercise and non-exercise groups. Shear modulus in the medial gastrocnemius at 10° dorsiflexion was significantly lower in the exercise group compared with the non-exercise group (34.2±7.7 vs. 46.5±13.1 kPa, P<0.05). These results suggest that daily exercise and training could affect muscle stiffness, but do not lead to an increase in muscle function.

Comparison of maximum joint angles during pole vaulting between male pole vaulters with and without lumbar disc degeneration or lumbar spondylolysis.

BACKGROUND: Pole vaulting involves trunk flexion, extension, and rotation, which may place the lumbar spine under stress. Repeated pole vaulting may cause lumbar disc degeneration (DD) and lumbar spondylolysis (LS); however, this phenomenon is yet to be established. OBJECTIVE: This study aimed to determine the difference in the maximum joint angles of the shoulder, hip, and trunk during pole vaulting between male pole vaulters with and without lumbar DD or LS. METHODS: This retrospective study included 17 male pole vaulters. Four high-speed cameras were used to record the pole vaulters at 240 Hz. Radiography and magnetic resonance imaging were used to examine the lumbar spine in all athletes. Differences in the data between two sets of groups were analyzed using the unpaired t-test or the Mann-Whitney U test. RESULTS: There was a significant difference in the maximum joint angle of hip flexion between pole vaulters with and without lumbar DD (p= 0.03). CONCLUSION: Pole vaulters with lumbar DD may use lumbar flexion instead of hip flexion during the rock-back movement. Moreover, LS may occur due to repeated failed vaulting. Therefore, trunk stability and functional movements should be prioritized to prevent organic changes in the lower back.

The prevalence of spondylolysis and intervertebral disc degeneration in male pole vaulters.

BACKGROUND: The lower back is the most common injury location in pole vaulters, but the prevalence of lumbar spondylolysis and intervertebral disc degeneration is not known. OBJECTIVE: This study aimed to determine the prevalence of lumbar spondylolysis and intervertebral disc degeneration in pole vaulters. METHODS: This cross-sectional study was conducted in the Tokai area of Japan and included 21 pole vaulters (mean ± standard deviation [range]: age, 22.2 ± 3.2 [18-28] years; height, 172.2 ± 4.7 [165.0-182.0] cm; body weight, 67.6 ± 7.3 [54.0- 80.0] kg). The majority of pole vaulters were collegiate athletes. We performed anterior, lateral, and oblique radiography at 45∘ and magnetic resonance imaging in the sagittal and coronal planes of the lumbar spine. The evaluation was performed independently of whether the athletes had lower back pain (LBP). Moreover, we investigated the duration of pole-vaulting experience and history and current presence of LBP using a questionnaire. RESULTS: The prevalence of lumbar spondylolysis and intervertebral disc degeneration was 28.6% (6/21) and 38.1% (8/21), respectively. Herniation was found in six discs in four vaulters (19.0%). All athletes had a history of LBP. The prevalence of lumbar spondylolysis was high (28.6%). CONCLUSIONS: Sport-specific movements performed by pole vaulters may be a risk factor for lumbar spondylolysis.

Surface markers and gene expression to characterize the differentiation of monolayer expanded human articular chondrocytes.

Autologous chondrocyte implantation (ACI) is a method of cartilage repair. To improve the quality of regenerated tissue by ACI, it is essential to identify surface marker expression correlated with the differentiation status of monolayer expanded human articular chondrocytes and to define the index for discriminating dedifferentiated cells from monolayer expanded human articular chondrocytes. Normal human articular chondrocytes were cultured in monolayer until passage 4. At each passage, mRNA expression of collagen type I, II, and X and aggrecan was analyzed by real-time quantitative PCR, and the surface marker expression of CD14, CD26, CD44, CD49a, CD49c, CD54, and CD151 was analyzed by fluorescence-activated cell sorting (FACS). The ratios of mRNA levels of collagen type II to I (Col II/Col I) represented the differentiation status of chondrocytes more appropriately during monolayer culture. The surface marker expression of CD44, CD49c, and CD151 was upregulated according to the dedifferentiation status, whereas that of CD14, CD49a, and CD54 was downregulated. The most appropriate combination of the ratio of Col II/Col I was CD54 and CD44. Cell sorting was performed using a magnetic cell sorting system (MACS) according to CD54 and CD44, and real-time quantitative PCR was performed for the cell subpopulations before and after cell sorting. The expression of collagen type II and aggrecan of the chondrocytes after MACS was higher than that before sorting, but not significantly. The mean fluorescence intensity (MFI) ratio of CD54 to CD44 could be an adequate candidate as the index of the differentiation status.

Inflammatory effect of advanced glycation end products on human meniscal cells from osteoarthritic knees.

OBJECTIVE: To investigate the inflammatory effects of advanced glycation end-products (AGEs) through the receptor for AGE in meniscal cells from osteoarthritic knees, and examine effects of hyaluronan (HA) on AGE-induced inflammation. METHODS: Meniscal cells from human osteoarthritic knees were cultured with or without glycolaldehyde-AGE-bovine serum albumin and 800 kDa HA. The amount of prostaglandin E(2) (PGE(2)) protein was determined using an enzyme immunoassay system. Expression of cyclooxygenase (COX)-1, COX-2, membrane associated prostaglandin E synthase (mPGES)-1 and cytosolic PGES (cPGES) was analyzed by real-time reverse transcription polymerase chain reaction and western blotting. RESULTS: PGE(2) synthesis was significantly increased by AGEs, and AGE-induced PGE(2) production was attenuated by addition of HA. While COX-2 and mPGES-1 expression was significantly upregulated by AGEs, COX-1 and cPGES expression was not affected by AGE. AGE-stimulated COX-2 and mPGES-1 expression was attenuated by HA through CD44 (HA receptor). However, the changes in COX-1 and cPGES expression were almost negligible. CONCLUSION: In meniscal cells from osteoarthritic knees, AGEs increased the production of inflammatory mediators, including PGE(2), COX-2 and mPGES-1. Furthermore, HA could decrease AGE-induced production of PGE(2), COX-2 and mPGES-1 through CD44.

Geranylgeranylacetone suppresses hydrogen peroxide-induced apoptosis of osteoarthritic chondrocytes.

BACKGROUND: Osteoarthritis (OA) is a common disease, afflicting many sufferers with both pain and functional disorders. Various therapies have been attempted for OA, but no fully effective treatment has been established yet. Apoptosis of chondrocytes caused by reactive oxygen species (ROS) has been considered important in the pathogenesis of OA. The progression of OA may be prevented by suppressing apoptosis of chondrocytes. Geranylgeranylacetone (GGA) has been used as an anti-ulcer drug in Japan for more than 20 years. Several recent studies have shown that GGA can induce heat shock protein (HSP) and exert cytoprotective actions on a large variety of cells and tissues. In this study, we investigated the effects of GGA on the apoptosis of OA chondrocytes induced by hydrogen peroxide (H(2)O(2)). METHODS: Human isolated OA chondrocytes were cultured in the absence or presence of GGA. Cell viability, caspase 3/7 and 9 activities, HSP70 mRNA and protein expressions were examined, and morphological analyses were conducted after exposure of cells to H(2)O(2) to induce apoptosis. RESULTS: Geranylgeranylacetone dose-dependently reversed the H(2)O(2)-induced decrease in cell viability. It was recognized that GGA rendered OA chondrocytes resistant to H(2)O(2)-induced apoptosis from Hoechst 33342 staining and TUNEL staining. Caspases 3 and 9 were activated by addition of H(2)O(2), and GGA suppressed this H(2)O(2)-induced activation of both caspases. H(2)O(2)-induced induction of HSP70 was enhanced in OA chondrocytes by pretreatment with GGA. The results showed that GGA can suppress apoptosis of chondrocytes and enhance production of HSP70. CONCLUSIONS: This study is the first, to our knowledge, to demonstrate that GGA protects OA chondrocytes from H(2)O(2)-induced apoptosis, at least in part by enhancing HSP70 production. These results indicate that GGA is a potentially useful drug for the treatment of OA.

Transplantation of marrow-derived mesenchymal stem cells and platelet-rich plasma during distraction osteogenesis--a preliminary result of three cases.

Clinical results of distraction osteogenesis with transplantation of marrow-derived mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) were reviewed in three femora and two tibiae of the two patients with achondroplasia and one patient with congenital pseudarthrosis of the tibia. MSCs derived from the iliac crest were cultured with osteogenic supplements and differentiated into osteoblast-like cells. PRP, which is known to contain several growth factors and coagulate immediately by a minute introduction of thrombin and calcium, was prepared just before transplantation. Culture-expanded osteoblast-like cells and autologous PRP were injected into the distracted callus with the thrombin-calcium mixture so that the PRP gel might develop within the injected site. Transplantation of MSCs and PRP was done at the lengthening and consolidation period in each patient. The target lengths were obtained in every leg without major complications and the average healing index was 23.0 days/cm (18.8-26.9 days/cm). Although these results are still preliminary, transplantation of osteoblast-like cells and PRP, which seemed to be a safe and minimally invasive cell therapy, could shorten the treatment period by acceleration of bone regeneration during distraction osteogenesis.

Inhibitory effects of cyclosporin A on calcium mobilization-dependent interleukin-8 expression and invasive potential of human glioblastoma U251MG cells.

Interleukin (IL)-8 produced from glioblastoma is suggested to contribute to its own proliferation and progression. Since various external stimuli have been shown to increase intracellular Ca(2+) in glioma cells, we investigated Ca(2+) mobilization-dependent IL-8 expression and effect of cyclosporin A (CsA), an inhibitor of calcineurin (Cn), on the expression and invasive potential of human glioblastoma U251MG cells. Combined treatment with Ca(2+)-ionophore and phorbol-myristate-acetate (A23187/PMA) increased IL-8 mRNA and protein levels. This increase was suppressed by CsA and by another Cn inhibitor FK506. Luciferase reporter gene assay and electrophoretic mobility shift assay revealed that activation of p65-containing nuclear factor-kappaB was essential for A23187/PMA-dependent activation of IL-8 promoter. CsA suppressed the promoter activity by attenuating IkappaB-alpha degradation. U251MG cells expressed IL-8 receptors CXCR-1 and -2, and Matrigel invasion assay revealed that CsA attenuated A23187/PMA-dependent stimulation of invasive potential, probably by inhibiting IL-8 production. In addition, IL-8-dependent proliferation was also suppressed by CsA. Taken together, these results demonstrate the novel inhibitory effects of CsA on glioblastoma cell functions, suggesting CsA as a potential therapeutic adjuvant for glioma treatment.

Calcium signaling pathway involving calcineurin regulates interleukin-8 gene expression through activation of NF-kappaB in human osteoblast-like cells.

UNLABELLED: Involvement of aberrant IL-8 production by osteoblasts was demonstrated in pathogenesis of inflammatory joint diseases. We thus investigated intracellular signaling pathways leading to IL-8 expression in human osteoblast-like HOS-TE85 cells. It was demonstrated that Ca2+ signaling pathway involving calcineurin regulates IL-8 gene expression through activation of a transcription factor, NF-kappaB. INTRODUCTION: Involvement of aberrant interleukin (IL)-8 production by osteoblasts was demonstrated in pathogenesis of inflammatory joint diseases. However, intracellular signaling pathways leading to IL-8 expression in osteoblasts have been poorly explored. Because a variety of external stimuli was shown to increase intracellular Ca2+ in osteoblasts, we investigated effects of Ca(2+)-ionophore and phorbol-myristate-acetate (Ion/PMA) on IL-8 expression in human osteoblast-like HOS-TE85 cells and compared the effects with those elicited by TNF-alpha. MATERIALS AND METHODS: HOS-TE85 cells were treated with Ion/PMA or TNF-alpha in the presence and absence of calcineurin inhibitors (CnI), cyclosporin A, and FK506. IL-8 mRNA levels and its promoter activities were examined by Northern blot and luciferase reporter analyses, respectively. Electrophoretic mobility shift assay (EMSA) was used to evaluate DNA binding activities of transcription factors such as NF-kappaB. Degradation of IkappaB, a cytoplasmic NF-kappaB-inhibitory protein, was examined by Western blot analysis. RESULTS: Ion/PMA and TNF-alpha induced IL-8 mRNA expression. Interestingly, CnI attenuated the induction by Ion/PMA, but not that by TNF-alpha. Promoter activity was also increased by both stimuli, and only the Ion/PMA-dependent increase was suppressed by CnI. Introduction of mutations in the promoter demonstrated that one NF-kappaB site was responsible for the suppression by CnI. EMSA revealed that this site binds with NF-kappaB containing p65 that was activated by Ion/PMA and TNF-alpha and that CnI inhibited only Ion/PMA-dependent NF-kappaB activation. Accordingly, CnI blocked only Ion/PMA-dependent degradation of IkappaB-alpha. In addition, the basal and Ion/PMA-dependent IL-8 promoter activities were enhanced by co-transfection of constitutively active calcineurin. CONCLUSION: These results show that the Ca2+ signaling pathway involving calcineurin regulates IL-8 gene expression through activation of NF-kappaB in human osteoblast-like cells.

Cyclosporin A enhances interleukin-8 expression by inducing activator protein-1 in human aortic smooth muscle cells.

OBJECTIVE: Cyclosporin A (CsA) and tacrolimus (FK506) are widely used as immunosuppressants. However, their use has been hampered by various adverse effects, such as acceleration of atherosclerosis. Interleukin (IL)-8, a chemotactic cytokine, plays an important role in pathogenesis of atherosclerosis. We thus investigated whether synthesis of IL-8 from primary human aortic smooth muscle cells is influenced by CsA and FK506. METHODS AND RESULTS: Northern blot analysis revealed that CsA increased IL-8 mRNA level and enhanced its increase by epidermal growth factor or tumor necrosis factor-alpha. In contrast, FK506 had no effect on the mRNA level. IL-8 accumulation in culture media was also increased by CsA. Stability of IL-8 mRNA was not affected by CsA, whereas luciferase reporter gene assay using the human IL-8 promoter revealed that CsA significantly augmented the promoter activity. Electrophoretic mobility shift assay showed that binding activity of activator protein (AP)-1 was increased by CsA, and introduction of a mutation into the AP-1 site in the promoter abolished its CsA-dependent activation. The increased AP-1 binding activity was accompanied by c-Fos synthesis. CONCLUSIONS: CsA stimulates synthesis of IL-8 via activation of AP-1 in human aortic smooth muscle cells, providing a novel aspect of biological effects of CsA on the cells.