The Study Of Correlation Between Obesity And Bone Mineral Density And The Effects Of Combined Administration Of Vitamin K2 And Collagen Peptides On Bone Metabolism

As the increase of the aging population and the numbers of overweight people,the disease of obesity,metabolic syndrome(MetS)and osteoporosis are causing attention worldwide.The specific correlation among the three diseases is currently unclear.On the one hand,obesity can promote bone formation,prevent osteoporosis,and reduce the risk of fractures,which as a protective factor for osteoporosis.On the other hand,obesity can cause visceral fat accumulation and release pro-inflammatory factors,high levels of pro-inflammatory factors stimulate osteoclast differentiation and absorption,thereby affecting the bone health.Therefore,to further clarify the relationship between obesity and osteoporosis,we investigated the correlation among bone mineral density(BMD),body composition,lipid metabolism and bone metabolism markers in obese patients.In addition,some reports have shown that MetS,which is characterized by abdominal obesity,blood glucose metabolism disorders,dyslipidemia and hypertension,plays an important role in regulating bone remodeling and bone metabolism.Thus,the correlation of MetS and its components with BMD and bone metabolism markers are also studied in our research.The current results will be helpful to provide a theoretical basis for prevention and early diagnosis of osteoporosis in obese and elderly MetS patients.It has been reported that the occurrence of osteoporosis and obesity is related to nutrition,genetic metabolism and other factors.Some studies shown that supplement vitamin K2(VK2)or hydrolyzed collagen(HC)alone can promote bone formation and prevent bone resorption.However,whether combined VK2 and HC application can improve bone metabolism and enhance bone protection in obese patients has not been reported yet.In order to further clarify the effect of the combined VK2 and HC application on bone metabolism in obese patients,we established a high-fat diet(HFD)induced obesity mice model,to investigate the mechanism of bone metabolism in obese mice after VK2 or/and HC administration.The current study includes the following three parts:Part 1: The correlation between BMD and body composition,lipid metabolism and bone metabolism in obese patientsIn this section,using cross-sectional research questionnaires,and screen outpatients according to the diagnostic criteria for obesity.Afterwards,the body composition,BMD,lipid metabolism index and bone metabolism index were measured,respectively.The results were shown that the body composition,bone metabolism index and lipid metabolism index were statistically related to BMD in obese patients,suggesting that obesity could cause the decrease of bone density and imbalance of bone metabolism.Thus,body composition,BMD,lipid metabolism index and bone metabolism index can be used for the clinical monitoring of BMD in obese patients.This can provide an important basis for the prevention and early diagnosis of osteoporosis in obese patients.Part 2: The correlation of MetS and its components with BMD and bone metabolism indexes in the elderly peopleIn this section,using cross-sectional research questionnaires,and screen outpatients according to the diagnostic criteria for Mets.Afterward,the blood biochemical indicators,bone metabolic indicators and BMD in different parts were measured.Statistical results showed significantly lower BMD in elderly MetS patients’ group,and a disorder of bone metabolism were observed in elderly MetS patients’ group.In addition,the components of MetS,such as the elevated level of the body mass index(BMI),systolic blood pressure(SBP),diastolic blood pressure(DBP),and fasting blood glucose(FPG),are negatively correlated with BMD and bone metabolism.However,the high-density lipids elevated protein(HDL)is positively correlated with BMD and bone metabolism indicators.It can be seen that MetS and its components are closely related to BMD and bone metabolism.Therefore,elderly MetS patients should be regularly screened for BMD and bone metabolism indicators,to prevent the occurrence of osteoporosis in elderly MetS patients.Part 3: The effect of VK2 combined with HC on bone metabolism and its mechanism in obese miceObesity has been implicated in the development of osteoporosis.Obesity is an important risk factor for osteoporosis and fragility fractures.To further study the relationship between obesity and osteoporosis,we established the obese mice model by fed a high-fat diet,and investigate the mechanism of bone metabolism after VK2 and / or HC application.Thirty 4-week-old C57BL/6J male mice were divided into five groups(Control,HFD,HFD-VK2,HFD-HC and HFD-VK2 + HC group).After 6 weeks of treatment,the BMD and bone metabolism indicators of mice were tested.The results show that the combined intervention of VK2 and HC can increase BMD and bone weight,up-regulate the expression of bone morphogenetic protein,and down-regulate the expression of pro-inflammatory factors.Moreover,the bone morphological parameters and cortical bone thickness(CT)returned to normal status.The results of immunohistochemistry and real-time quantitative PCR indicated that the combined nutritional intervention of VK2 and HC can effectively inhibit bone resorption.In summary,our results suggested that combined VK2 and HC increase the ratio of OPG/RANKL and inhibit activation of the RANKL/NF-κB signaling pathway,subsequently inhibit the development of osteoclasts.It can be seen that the combined intervention of VK2 and HC more effectively promotes bone formation and inhibits bone resorption,this study provides valuable insights into the pathogenesis of osteoporosis,and provides new ideas for the prevention of osteoporosis in obese patients.