“脾肾相关”理论探讨脂肪源性外泌体在老年性骨质疏松症中的研究进展

中医学脾肾相关理论高度概括了老年性骨质疏松症(senile osteoporosis,SOP)骨骼和脂肪的内在关系,外泌体作为一种细胞囊泡可携带多种生物活性分子在“骨-脂肪Crosstalk”中发挥关键调控作用。笔者基于脾肾相关理论探讨脂肪源性外泌体在SOP中的作用,对挖掘中医药防治SOP的新靶点及丰富脾肾相关理论的现代科学内涵具有重要意义。中医学调理脾肾是治疗SOP“骨脂代谢失衡”的关键,为防治SOP提供了新的视角。

基于“骨肉不相亲”理论的补肾健脾法对骨质疏松症动物模型骨-肌肉-脂肪轴调节作用研究述评

探讨补肾健脾中药及针灸穴位治疗骨质疏松症的作用与调节骨-肌肉-脂肪轴的相关性,以骨肉不相亲、骨质疏松症、补肾健脾、骨-肌肉-脂肪轴为关键词,通过中国知网、万方、维普等中文期刊数据库检索2009至2019年的相关文献报道,以与骨质疏松症发生密切相关的骨、骨骼肌和脂肪的系列指标为切入点进行归纳总结。结果显示,补肾健脾中药及针灸穴位对骨质疏松症模型动物骨、肌肉、脂肪等病理改变均有良性调节作用,提示补肾健脾法通过多靶点、多层次、系统性地对骨-肌肉-脂肪轴进行整体调节,从而有效地防治骨质疏松症,此为中医“骨肉不相亲”理论提供了可靠的实验室依据。

Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose

Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM.

Non-alcoholic fatty liver disease connections with fat-free tissues: A focus on bone and skeletal muscle

The estimates of global incidence and prevalence of non-alcoholic fatty liver disease(NAFLD) are worrisome, due to the parallel burden of obesity and its metabolic complications. Indeed, excess adiposity and insulin resistance represent two of the major risk factors for NAFLD; interestingly, in the last years a growing body of evidence tended to support a novel mechanistic perspective, in which the liver is at the center of a complex interplay involving organs and systems, other than adipose tissue and glucose homeostasis. Bone and the skeletal muscle are fat- free tissues which appeared to be independently associated with NAFLD in several cross-sectional studies. The deterioration of bone mineral density and lean body mass, leading to osteoporosis and sarcopenia, respectively, are age-related processes. The prevalence of NAFLD also increases with age. Beyond physiological aging, the three conditions share some common underlying mechanisms, and their elucidations could be of paramount importance to design more effective treatment strategies for the management of NAFLD. In this review, we provide an overview on epidemiological data as well as on potential contributors to the connections of NAFLD with bone and skeletal muscle.

Adipose-derived stromal cells resemble bone marrow stromal cells in hepatocyte differentiation potential in vitro and in vivo

AIM To investigate whether mesenchymal stem cells(MSCs) from adipose-derived stromal cells(ADSCs) and bone marrow stromal cells(BMSCs) have similar hepatic differentiation potential.METHODS Mouse ADSCs and BMSCs were isolated and cultured. Their morphological and phenotypic characteristics, as well as their multiple differentiation capacity were compared. A new culture system was established to induce ADSCs and BMSCs into functional hepatocytes. Reverse transcription polymerase chain reaction, Western blot, and immunofluorescence analyses were performed to identify the induced hepatocytelike cells. CM-Dil-labeled ADSCs and BMSCs were then transplanted into a mouse model of CCl4-induced acute liver failure. fluorescence microscopy was used to track the transplanted MSCs. Liver function was tested by an automatic biochemistry analyzer, and liver tissue histology was observed by hematoxylin and eosin(HE) staining.RESULTS ADSCs and BMSCs shared a similar morphology and multiple differentiation capacity, as well as a similar phenotype(with expression of CD29 and CD90 and no expression of CD11 b or CD45). Morphologically, ADSCs and BMSCs became round and epithelioid following hepatic induction. These two cell types differentiated into hepatocyte-like cells with similar expression of albumin, cytokeratin 18, cytokeratin 19, alpha fetoprotein, and cytochrome P450. fluorescence microscopy revealed that both ADSCs and BMSCs were observed in the mouse liver at different time points. Compared to the control group, both the function of the injured livers and HE staining showed significant improvement in the ADSC-and BMSC-transplanted mice. There was no significant difference between the two MSC groups.CONCLUSION ADSCs share a similar hepatic differentiation capacity and therapeutic effect with BMSCs in an acute liver failure model. ADSCs may represent an ideal seed cell type for cell transplantation or a bio-artificial liver support system.

Hepatogenic differentiation of human mesenchymal stem cells from adipose tissue in comparison with bone marrow mesenchymal stem cells

AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNF4α）, as demonstrated by adenoviral expression vectors.CONCLUSION： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.

Increased fatty acid synthase as a potential therapeutic target in multiple myeloma

Objective： To determine fatty acid synthase （FAS） expression in human multiple myeloma and verify its potential as a therapeutic target in multiple myeloma. Methods： FAS expression was determined by immunohistochemistry, reverse-transcription polymerase chain reaction （RT-PCR） and immunoblot analysis in bone marrow samples obtained from 27 patients with multiple myeloma （MM patients） and peripheral blood mononuclear cells （PBMCs） obtained from 12 healthy donors In parallel, additional analyses were performed on 2 human multiple myeloma cell lines, U266 and RPM18226. U266 cells were treated with cerulenin at various concentrations （5 to 320 μg/ml） for 24 h, and metabolic activity was measured by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assays. Apoptosis was evaluated by dual Annexin V/Pl （propidium iodide） labeling and flow cytometry （FCM） in U266 cells treated with 20 μg/ml cerulenin for 12 h or 24 h. Results： By immunohistochemistry, we found that 19 of 27 bone marrow samples obtained from MM patients expressed significantly high levels of FAS. Similarly, by RT-PCR, 22 of 27 bone marrow samples obtained from MM patients, U266 and RPM18226 showed FAS expression, whereas PBMC samples from 12 healthy donors did not express detectable level of FAS. FAS protein expression was confirmed by immunoblot analysis in 16 of 27 bone marrow samples obtained from MM patients, U266 and RPM18226 cell lines, and no FAS protein expression was detected in PBMC samples from 12 healthy donors. U266 cells were highly sensitive to cerulenin treatment, with a dosage-related effect on metabolic activity, as a measure for cell proliferation. U266 cells treated with 20 μg/ml cerulenin for 12 and 24 h also showed early sign of apoptosis with 56.9% and 69.3% Annexin V^＋/Pl cells, and late apoptotic and necrotic cells with 3.2% and 17.6% Annexin V^＋/Pl^＋ cells. Conclusion： Increased FAS expression existed in multiple myeloma samples and human myeloma cell lines. Cerulenin greatly inhibited metabolic activity/cell proliferation of U266 cells and induced apoptosis, suggesting that FAS is an effective target for pharmacological therapy in human multiple myeloma.

An unreported complication of acute pancreatitis

Acute pancreatitis constitutes 3% of all admissions with abdominal pain. There are reports of osteal fat necrosis leading to periosteal reactions and osteolytic lesions following severe pancreatitis, particularly in long bones. A 54-year-old man was admitted to our hospital with acute pancretitis, who later developed spinal discitis secondary to necrotizing pancreatitis. He was treated conservatively with antibiotics and after a month he recovered completely without any neurological deficit. This case is reported for its unusual and unreported spinal complications after acute pancreatitis.

Relationship between peak oxygen uptake and regional body composition in Japanese subjects

Purpose： To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry （DEXA） in Japanese subjects. Methods： A total of 93 men （42.2 ± 12.3 years old） and 106 women （43.5 ± 12.3 years old） were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated. Results： Peak oxygen uptake was 37.6± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage （men： r = -0.684, p 〈 0.0001; women： r = -0.681, p 〈 0.0001）. These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass. Conclusion： Peak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects. Copyright

Baicalin attenuates high fat diet-induced insulin resistance and ectopic fat storage in skeletal muscle,through modulating the protein kinase B/Glycogen synthase kinase 3 beta pathway

Insulin resistance is the pathophysiological basis of many diseases.Overcoming early insulin resistance highly significant in prevention diabetes,non-alcoholic fatty liver,and atherosclerosis.The present study aimed at evaluating the therapeutic effects of baicalin on insulin resistance and skeletal muscle ectopic fat storage in high fat diet-induced mice,and exploring the potential molecular mechanisms.Insulin resistance in mice was induced with a high fat diet for 16 weeks.Animals were then treated with three different doses of baicalin(100,200,and 400 mg·kg^(-1)·d^(-1)for 14 weeks.Fasting blood glucose,fasting serum insulin,glucose tolerance test(GTT),insulin tolerance test(ITT),and skeletal muscle lipid deposition were measured.Additionally,the AMP-activated protein kinase/acetyl-CoA carboxylase and protein kinase B/Glycogen synthase kinase 3 beta pathways in skeletal muscle were further evaluated.Baicalin significantly reduced the levels of fasting blood glucose and fasting serum insulin and attenuated high fat diet induced glucose tolerance and insulin tolerance.Moreover,insulin resistance was significantly reversed.Pathological analysis revealed baicalin dose-dependently decreased the degree of the ectopic fat storage in skeletal muscle.The properties of baicalin were mediated,at least in part,by inhibition of the AMPK/ACC pathway,a key regulator of de novo lipogenesis and activation of the Akt/GSK-3β pathway,a key regulator of Glycogen synthesis.These data suggest that baicalin,at dose up to 400 mg·kg^(-1)·d^(-1),is safe and able to attenuate insulin resistance and skeletal muscle ectopic fat storage,through modulating the skeletal muscle AMPK/ACC pathway and Akt/GSK-3β pathway.

Adipose-derived stem cells transfected with pEGFP-OSX enhance bone formation during distraction osteogenesis

This study was designed to investigate the effects of local delivery of adipose-derived stem cells （ADSCs） transfected with transcription factor osterix （OSX） on bone formation during distraction osteogenesis. New Zealand white rabbits （n=54） were randomly divided into three groups （18 rabbits per group）. A directed cloning technique was used for the construction of recombinant plasmid pEGFP-OSX, where EGFP is the enhanced green fluorescence protein. After osteodistraction of the dght mandible of all experimental rabbits, rabbits in group A were treated with ADSCs transfected with pEGFP-OSX, group B with ADSCs transfected with pEGFP-N1, and group C with physiological saline. Radiographic and histological examinations were processed after half of the animals within each group were humanely killed by injection of sodium pentothal at Week 2 or 6 after surgery. The distraction bone density was measured as its projectional bone mineral density （BMD）. Three parameters were measured, namely, the thickness of new trabeculae （TNT）, and the volumes of the newly generated cortical bone （NBV1） and the cancellous bone （NBV2） of the distracted regions. Good bone generation in the distraction areas was found in group A, which had the highest BMD, TNT, and NBV in the distraction zones among the groups. There was no significant difference in bone generation in the distraction areas between groups B and C. The results indicate that the transplantation of ADSCs transfected with pEGFP-OSX can effectively promote bone generation during distraction in vivo.

Osteogenic capability of autologous rabbit adipose-derived stromal cells in repairing calvarial defects

Objective： To evaluate the in vitro and in vivo osteogenic capability of adipose-derived stromal cells （ASCs）.Methods： ASCs were isolated from New Zealand white rabbits and determined by alkaline phosphatase （ALP）staining, von Kossa staining and alizarin red staining. Some specific markers ofosteogenic differentiation, including ALP,osteocalcin （OCN）, osteopontin （OPN） were examined by reverse transcription-polymerase chain reaction （RT-PCR）.In vivo, demineralized bone matrix （DBM）-ASCs composites were implanted into the rabbit calvarial defects created at each side of the longitudinal midline. After 6 weeks, histologic properties of the transplants were analyzed.Results： ASCs were successfully induced into osteogenesis. ALP staining, von Kossa staining and alizarin red staining showed positive results. The expressions of ALP, OCN and OPN were detected in ASCs after cultivation in osteogenic medium. Extensive new bone was observed in the defects transplanted with DBM-ASCs composites.Conclusion： ASCs have the potential to differentiate into osteogenic lineage and DBM-ASCs constructs are a promising method for regeneration in bone defects.

Uninduced adipose-derived stem cells repair the defect of full-thickness hyaline cartilage

Objective： To testify the effect of the stem cells derived from the widely distributed fat tissue on repairing full-thickness hyaline cartilage defects. Methods： Adipose-derived stem cells （ADSCs） were derived from adipose tissue and cultured in vitro. Twenty- seven New Zealand white rabbits were divided into three groups randomly. The cultured ADSCs mixed with calcium alginate gel were used to fill the full-thickness hyaline cartilage defects created at the patellafemoral joint, and the defects repaired with gel or without treatment served as control groups. After 4, 8 and 12 weeks, the reconstructed tissue was evaluated macroscopically and microscopically. Histological analysis and qualitative scoring were also performed to detect the outcome.Results： Full thickness hyaline cartilage defects were repaired completely with ADSCs-derived tissue. The result was better in ADSCs group than the control ones. The microstructure of reconstructed tissue with ADSCs was similar to that of hyaline cartilage and contained more cells and regular matrix fibers, being better than other groups. Plenty of collagen fibers around cells could be seen under transmission electron microscopy. Statistical analysis revealed a significant difference in comparison with other groups at each time point （t=4.360, P〈0.01）. Conclusion： These results indicate that stem cells derived from mature adipose without induction possess the ability to repair cartilage defects

CIDE gene expression in adipose tissue,liver,and skeletal muscle from obese and lean pigs

The expression of the cell death-inducing DNA fragmentation factorα-like effector（CIDE）family including Cidea,Cideb,and Cidec was significantly increased in mouse and human models of obesity.However,there was less information on these genes’expression in pigs.Here,we hypothesized that different fat accumulation between lean（Duroc×Landrace×Yorkshire gilts,DLY）and obese（Lantang）pigs was attributed to porcine CIDE-modulating lipid metabolism.Our data showed that Cidea and Cidec were expressed at a high level in adipose tissue,and at a relatively high level in skeletal muscle,whereas Cideb was mainly expressed in the liver in both breeds of pig.Lantang pigs had higher white adipose and skeletal muscle Cidea and Cidec mR NA abundance,and hepatic and muscle Cideb mR NA than DLY pigs.Lipid metabolism-related genes including sterol regulatory element binding protein 1c（SREBP-1c）,hepatocyte nuclear factor-4α（HNF-4α）,peroxisome proliferator-activated receptorγcoactivator-1α（PGC-1α）,fatty acid synthase（FASN）,diacylglycerol O-acyltransferase 1（DGAT1）,and DGAT2 showed a higher expression level in adipose tissue from obese pigs than in that from lean pigs.Lantang pigs exhibited higher mR NA abundance for liver SREBP-1c,HNF-4α,and PGC-1α,and higher skeletal muscle SREBP-1c,HNF-4α,PGC-1α,and DGAT2 expression,as compared with DLY pigs.However,the perlipin2 mR NA levels in adipose tissues,liver,and skeletal muscle were significantly lower in obese pigs than in their lean counterparts.Furthermore,plasma non-esterified fatty acid（NEFA）,glucose,and triacylglycerol（TAG）levels were greater in obese pigs than in lean pigs.Finally,data from correlation analysis further found that CIDE mR NA expression was positively correlated with back fat thickness（BFT）,abdominal fat mass（AFM）,and the levels of NEFA,TAG,and glucose in the two breeds.Collectively,these data revealed that the porcine CIDEs possibly modulated lipid metabolism and contributed to the development of fat deposition and obesity in Lantang pigs.

Express,on of GLUT4 mRNA of peripheral tissues and insulin resistance in rats with severe traumatic brain injury

Objective： To evaluate the expression of glucose transporter-4 （GLUT4） mRNA in skeletal muscle and subcutaneous adipose tissues and investigate the mechanism of posttraumatic insulin resistance. Methods： Sixteen adult male Wistar rats were randomly divided into 2 group （ n = 8 in each group）, i.e., severe traumatic brain injury （TBI） group due to falls from a height and normal control group. Blood glucose and serum insulin were measured at 0.5 h before trauma and 3 h, 24 h, 72 h, 7 d after trauma, respectively. And insulin sensitivity was calculated by insulin activity index （IAI） formula. Skeletal muscle and subcutaneous adipose tissue samples were collected at the same time when blood was sampled. The changes of expression of GLUT4 mRNA were observed using reverse transcription-polymerase chain reaction （RT-PCR）. Results： Accompanied by the decrease of insulin sensitivity, the expression of GLUT4 mRNA was significantly decreased in adipose tissues at 24 h and 72 h after trauma （ P 〈 0. 01 ）, however, such phenomena did not appear in skeletal muscle samples. Conclusions： To some extent, the development of posttraumatic insulin resistance is related to the abnormality of transcription activity of GLUT4 gene. Adipose tissues show some difference in the transcriptional level of GLUT4 gene after trauma as compared with skeletal muscle tissues.