Research On The Treatment Effect Of Low Frequency Pulsed Electromagnetic Fields On Postmenopausal Osteoporosis

As the population aging has been a problem and developed gradually, theincidence of osteoporosis has raised up year by year, the epidemiology researchinvestigate that about one third post-menopause women get osteoporosis causedby estrogen deficiency. For post-menopause women, their estrogen level willlower rapidly and lead to lost of cancellous bone quickly. Right now, hormonereplacement therapy is the first selected treatment for prevention of PMO;however, its obvious toxicity and side effect, as well as the risk of breast cancerand endometrial cancer limite clinical apply of PMO. There has been more thanone century explore on application of electromagnetic technique in orthopedicsdiseases therapy, since 90's, our country have began to do research onosteoporosis treatment by pulsed electro magnetic fields(PEMFs), which choseintelligentification physical electromagnetic field therapy to improve organismbasal metabolism, and acted on skeleton cells through anti-harmonic frequencyalternation electromagnetic field produced by comprehensiveness high energygenerator, which activated osteoblast and promoted their caryocinesia therefore made a transformation from osteoblast to bone cell, thus could improve bonearchitecture, increase bone density and as a result to cure osteoporosis.Research on magnetic field heat and non-heat biological effect has been agreat interest for bioengineering both in domestic and abroad. Scientists paymuch attention to heat biological effect .past, but in this decade, non-heatbiological effect attracted their interest and concentrated on research about it.This thesis developed a GZY osteoporosis therapy instrument based on themechanism of non-heat biological effect caused by low intensity(1×10^-6T)pulsating magnetic fields(PEMFs) and combined calculation of electromagneticfield theory, also investigated the effect of low intensity PEMFs on osteoporosisby evaluating the instrument therapeutic effect with osteoporosis animal models,therefore expected to provide a new idea and theory basis for osteoporosisprevention and therapy.This thesis evaluated the effect of low intensity PMFs on osteoporosis byanimal models (remove ovaries operation model which simulatedpost-menopause women osteoporosis), expected to find a new approach andtheory basis for osteoporosis prevention and therapy and investigated thetherapeutic effect on post menopause osteoporosis rats and appraised the safetywith long term use.Chose 50 female SD rat, 3-5 months old, 250±20g weight, after adapt breedfor 1 week, they were divided to five groups at random, which were shamoperation (Sham), osteoporosis model (Model), Xian Ling Gu Baoadministration group(XLGB), PEMFs radiation group(PEMFs), Xian Ling GuBao plus PEMFs radiation group(XLGB+PEMFs). Besides Sham, the other fourgroups were all two sides oophorectomized to copy the osteoporosis model.After 4 weeks, treated different groups according to scheme of below for 12 weeks: Sham (1.0 mL·Kg^-1·d^-1NS), Model (1.0 mL·Kg^-1·d^-1NS), XLGB (0.31g·Kg^-1·d^-1NS), PEMFs (PEMFs radiation 8h·d^-1), XLGB+ PEMFs (0.31g·Kg^-1·d^-1NS+PEMFs radiation 8h·d^-1).During therapy periods, observed general physical sign continuously,recorded weight and ingest amount each week, collected urines when one weekbefore the end of experiment, after the experiment, executed animals and obtainblood via abdominal aorta, detected calcium(Ca), phosphonium(P), alkalinephosphates (ALP) etc level in plasma and urine, got heart, liver, spleen, lung,kidney, adrenal gland, thymus, brain, uterus etc organs, separated femoral boneand determined the bone density(BMD), biomechanics and pathologyindicator.1.General physical sign results: observed their weight change day by day,two weeks after the operation, compared with Sham, rat in Model, XLGB,PEMFs and XLGB+PEMFs put on weight rapidly, showed obvious difference(P <0.05), on contrary, Sham put on weight slowly, however the phenomenonwas coincidence with post-menopause women; when began to therapy, themodel group animals weight increased slowly, while Sham didn't show greatchanges, but XLGB, PEMFs and XLGB+PEMFs groups lost weight at differentextent, these three groups were all showed obviously difference compared tomodel (P<0.05).2.Urine biochemical indicator: compared to Sham, the ALP, Ca, P levels ofthe other four groups were all had significantly different (P <0.01), indicatedmodel be successful, when compared with Model, Sham showed significantlydifference in ALP (P <0.01), while PEMFs and XLGB+PEMFs groups wereobvious difference (P <0.05); for P value, PEMFs showed significantlydifference (P <0.01), while XLGB+PEMFs groups was only obvious difference(P<0.05). 3.Blood biochemical indicator: compared with Model, Sham showedsignificantly difference in ALP (P <0.01), while PEMFs and XLGB+PEMFsgroups were obvious difference (P <0.05); for P value, Sham and PEMFsshowed significantly difference (P <0.01), but XLGB+PEMFs groups was onlyobvious difference (P <0.05).4.Organ index and organ/weight ratio:compared with Sham, Model,XLGB, PEMFs and XLGB+PEMFs were all showed significantly different inuterus coefficient (mg/g) (P <0.01), and compared with Model, Sham alsoshowed significantly difference (P <0.01), while XLGB was obvious differencewhich indicated that XLGBcould improve estrogen deficiency(P <0.05).5.BMD results:compared with Model, Sham and XLGB+PEMFs bothshowed significantly difference (P <0.01), while XLGB and PEMFs wereobvious difference which demonstrated BMD was reinforced after drug orPEMFs therapy.6.Femoral bone biomechanics indicator: bear stress of Sham andXLGB+PEMFs both showed significantly difference (P <0.01), while XLGBand PEMFs were obvious difference which demonstrated bear stress wasreinforced after PEMFs or/and drug therapy.7.Femoral bone pathology indicator: determined BMD, BMC, BV/TV,Conn.D, SMI , Tb.N, Tb.Th, Tb.SP value and made compare among groups,when compared with Model, all groups showed significantlydifference(P <0.01), which implied that after PEMFs therapy, BMD,BMC,BV/TV,CONN.D,TB.N,Tb.Th were increased significantly(P <0.01); and SMI,Tb.SPvalue were reduced significantly (P<0.01).8.Ingest amount: detected the food uptake every week during exp, whichModel, XLGB, PEMFs and XLGB+PEMFs groups had no difference with Sham (P >0.05), indicated oophorectomized operation had no influence on food anddrink.9.Organ and organ/weight ratio: removed rat organs(heart, liver, spleen,lung, kidney, adrenal gland, thymus, brain), weighted and compared amongthose groups, however it took on no differences (P >0.05), indicated PEMFstherapy had no effect on important organs. Compared Sham with the other fourgroups there were also no differences in important organ coefficient (mg/g)(P >0.05), demonstrated oophorectomized operation didn't affect heart, liver,spleen, lung, kidney, adrenal gland, thymus, brain.10.Liver and renal function detect: Compared Sham with the other fourgroups, there were no differences inAST,URE,CRE,ALB,TP,GLU,BIL,CHO,TRIGLvalue (P>0.05), demonstrated after 3 months therapy, no changeshappened to liver and renal function, indicated PEMFs was safe for osteoporosisrat.We used low intensity, low frequency PEMFs to treat osteoporosis rat,where the intensity was15Gs PEMFs(f=15Hz,r=5ms) and exposed to magneticfields 8h·d^-1. Compared with Model, after treatment by PEMFs to PMO rat, theyput on weight slowly, BMD and femoral bone bear stress significantlyincreased,Ca, P, ALP level in plasma improved well, so PEMFs showed good treatmenteffect on PMO rat originated bypost-menopause estrogen deficiency.Observed general physical sign, food uptake, detected blood biochemicalindicator, dissected animals'organ; after statistics analysis, we found that evenafter 3 months therapy, there was no influence on liver and renal function, theimportant organ coefficient showed no difference between normal group, hintedPEMFs was safe for osteoporosis rat.