ABSTRACT
BACKGROUND:Clinical studies have found good analgesic effects of silver needle-thermal conduction therapy in patients with myofascial pain syndrome,but the exact mechanism remains unclear. OBJECTIVE:To observe the effect of silver needle-thermal conduction therapy on silent information regulator homolog 3(SIRT3)changes and mitochondrial ultrastructure in a rat model of myofascial pain syndrome. METHODS:Twenty rats were randomly selected from 26 Sprague-Dawley rats and were subjected to percussion combined with motor fatigue for replicating the rat model of myofascial pain syndrome.Sixteen rats that were successfully modeled were randomly divided into model group and silver needle-thermal conduction therapy group(treatment group),with eight rats in each group.The remaining rats were used as controls(normal group).The treatment group was treated with silver needle-thermal conduction therapy.Mechanical withdrawal threshold and thermal withdrawal latency of rats were measured at 1 day before modeling,1 day after modeling and 14 days after treatment.Electromyographic activities of the right medial femoral muscle were measured at 14 days after treatment.The right medial femoral muscle tissue was taken for hematoxylin-eosin staining to observe the local morphology and for transmission electron microscopy to observe the mitochondrial ultrastructure.Western blot assay was performed to detect SIRT3 expression. RESULTS AND CONCLUSION:Pain threshold:The mechanical withdrawal threshold and thermal withdrawal latency of the model and treatment groups were significantly decreased compared with those in the normal group and before modeling(P＜0.01).After treatment,the mechanical withdrawal threshold and thermal withdrawal latency of rats were significantly higher in the treatment group compared with the model group(P＜0.01).Electromyography:The rats in the model group showed spontaneous electrical activity in the right medial femur,while the rats in the treatment group showed reduced spontaneous electrical activity,longer time frame(P＜0.01)and lower wave amplitude(P＜0.05)compared with the model group.Hematoxylin-eosin staining:In the normal group,rat muscle fibers arranged closely and regularly.In the model group,the muscle fibers of rats were atrophied,degenerated,and disordered in arrangement.In the treatment group,rat muscle structure disorder improved.Mitochondrial microstructure:Under the transmission electron microscope,mitochondrial structure in the normal group was normal;mitochondrial swelling with broken or disappeared cristae appeared in the model group;mitochondrial swelling in the treatment group was obviously relieved or tended to be normal.SIRT3 expression:SIRT3 expression was significantly downregulated in the model group compared with the normal group,but was significantly upregulated in the treatment group compared with the model group(P＜0.05).To conclude,abnormalities in local muscle mitochondria and downregulation of SIRT3 expression suggest the presence of impaired energy metabolism in the rat model of myofascial pain syndrome.Mitochondrial changes recover and are close to normal after the silver needle-thermal conduction therapy,and the expression of SIRT3 is also upregulated close to the normal group,indicating the silver needle-thermal conduction therapy may play a therapeutic role by promoting mitochondrial repair and improving energy metabolism disorder.
ABSTRACT
<p><b>BACKGROUND</b>Genetic factors are important in the pathogenesis of osteoporosis, but less is known about the genetic determinants of osteoporosis treatment. We aimed to explore the association between the gene polymorphisms of key enzyme farnesyl diphosphate synthase (FDPS) in mevalonate signaling pathway of osteoclast and response to alendronate therapy in osteoporotic postmenopausal women in China.</p><p><b>METHODS</b>The study group comprised 639 postmenopausal women aged (62.2 ± 7.0) years with osteoporosis or osteopenia who had been randomly assigned to low dose group (70 mg/2 w) or standard dose group (70 mg/w) of alendronate in this 1-year study. We identified allelic variant of the FDPS gene using the polymerase chain reaction and restriction enzyme Faul. Before and after treatment, serum levels of calcium, phosphate, alkaline phosphatase (ALP), cross linked C-telopeptide of type I collagen (β-CTX) were detected. Bone mineral density (BMD) at lumbar spine and proximal femur was measured. The association was analyzed between the polymorphisms of FDPS gene and the changes of BMD, bone turnover biomarkers after the treatment.</p><p><b>RESULTS</b>The FDPS rs2297480 polymorphisms were associated with baseline BMD at femoral neck, and patients with CC genotype had significantly higher baseline femoral neck BMD ((733.6 ± 84.1) mg/cm(2)) than those with AC genotypes ((703.0 ± 86.9) mg/cm(2)) and AA genotypes ((649.8 ± 62.4) mg/cm(2)) (P < 0.01). No significant difference in BMD at lumbar spine was observed among different genotypes of FDPS. The percentage change of serum ALP level was significantly lower in patients with CC genotype (-22.9%) than that in those with AC genotype (-24.1%) and AA genotype (-29.8%) of FDPS after 12 months of alendronate treatment (P < 0.05). Neither percentage change of BMD nor β-CTX level after alendronate treatment had association with FDPS genotype.</p><p><b>CONCLUSIONS</b>FDPS gene was probably a candidate gene to predict femoral neck BMD at baseline. FDPS gene alleles could predict change percentage of ALP after treatment of alendronate, but possibly had no significant relationship with the responsiveness of BMD to alendronate therapy.</p>