To investigate icariin’s regulation of marrow fatty acid metabolism and stearoyl-CoA desaturase (SCD) indices in preventing ovariectomy-induced osteoporosis. Thirty-six female Sprague-Dawley rats underwent sham surgery or ovariectomy and were treated with either icariin (125 mg/kg/day) or vehicle via oral gavage for 12 weeks, 6 days per week. Bone marrow was collected from tibias for fatty acid profiling via gas chromatography–mass spectrometry. Serum levels of bone-specific alkaline phosphatase (BALP) and tartrate-resistant acid phosphatase 5b (TRACP-5b) were measured using Enzyme-Linked Immunosorbent Assay. Tibial trabecular microstructure was assessed by micro-CT. Ovariectomy significantly altered marrow fatty acid composition, marked by increased palmitic acid (C16:00) and palmitoleic acid (C16:1 n-7), decreased stearic acid (C18:00) and arachidonic acid (C20:4 n-6), and elevated SCD indices. These changes were associated with deteriorated bone microarchitecture and impaired bone turnover. Icariin treatment effectively normalized marrow fatty acid levels, suppressed SCD indices, and consequently attenuated bone loss by improving bone volume fraction, trabecular number, and thickness, while reducing trabecular separation. Additionally, icariin restored the balance of bone turnover markers, increasing BALP and decreasing TRACP-5b. Significant correlations were identified between specific fatty acids and both bone structural parameters and remodeling markers. Icariin attenuates osteoporotic bone loss by preventing ovariectomy-induced disturbances in marrow fatty acid metabolism, particularly through the suppression of SCD indices and normalization of C16:00, C16:1 n-7, and C18:00 levels. This study highlights the critical role of lipid homeostasis in bone integrity and identifies icariin as a promising lipid-modulating candidate for postmenopausal osteoporosis.

Purpose:This study aimed to evaluate the effectiveness of fractal analysis in distinguishing between benign and malignant breast lesions based on tumor subregion complexity and spatial heterogeneity. Material and methods:Breast diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data from biopsy- and surgery-confirmed malignant (n = 75) and benign tumors (n = 32) were used to evaluate the whole-lesion heterogeneity and subregional fractal dimension (FD) using habitat imaging. Inter-reader variability in 3D region of interest definition was assessed using the Dice similarity coefficient. Receiver operating characteristic curve (ROC) analysis was conducted to assess the diagnostic performance of studied parameters in differentiating benign from malignant lesions. Results:The overall Dice similarity coefficient across all lesion classes was 0.86 (95% confidence interval [CI]: 0.79-0.96). The inter-reader reliability was excellent, with intraclass correlation coefficients > 0.90 for FD. Significant differences were observed between malignant and benign lesions in hypervascular cellular FD (p < 0.001) and hypovascular cellular FD (p = 0.011), but not in nonviable tissue FD (p = 0.568). Patients with malignant lesions exhibited significantly higher median heterogeneity of the whole lesion compared to those with benign lesions (p = 0.015). Among the FD features generated by habitat imaging, hypervascular cellular FD had the highest area under the ROC curve (0.925, 95% CI: 0.854-0.969), surpassing the total heterogeneity (0.671, 95% CI: 0.568-0.763). Sensitivity and specificity of 89.3% and 81.8%, respectively, were achieved in distinguishing benign from malignant lesions. Conclusions:Subregional FD of tumor habitats demonstrated superior diagnostic accuracy in differentiating between benign malignant breast tumors compared to the heterogeneity of the whole lesion.

This review examines the role of marrow adipose tissue fatty acid composition in skeletal homeostasis, focusing on osteoporosis. To avoid conceptual confusion, we define evidence tiers: human studies assessing endogenous marrow lipid profiles; mechanistic studies applying exogenous fatty acids in vitro and in vivo; indirect MRI-based surrogates of marrow fat quantity; and direct ex vivo measurements of fatty acid composition via GC-MS, LC-MS, and lipidomics. We also clarify the distinction between marrow fat quantity and fatty acid quality. Human data reveal disease-, age-, and site-related alterations in marrow lipid saturation and unsaturation; however, findings vary by skeletal site, marrow compartment, fracture status, analytical platform, and study population. Experimental evidence demonstrates that saturated fatty acids (e.g., palmitic acid) induce lipotoxicity and osteoblast dysfunction, whereas unsaturated fatty acids (e.g., oleic acid and n-3 polyunsaturated fatty acids) exert protective effects via modulation of mesenchymal stem cell differentiation, osteoclastogenesis, ferroptosis, autophagy, and mitochondrial metabolism. Collectively, current evidence supports an association between marrow fatty acid biology and osteoporotic bone loss. Causal, diagnostic, and therapeutic implications remain preliminary. This review's main contribution is a fatty-acid-centered framework that integrates evidence tiers, molecular categories, and skeletal-site heterogeneity, guiding future research.

Breast cancer heterogeneity is crucial for treatment decision-making and prognosis prediction. Magnetic resonance imaging (MRI) is a key tool in breast imaging, providing a non-invasive assessment of morphological characteristics, cell density, hemodynamics, and vascular proliferation. Integrating MRI with advanced techniques such as radiomics, habitat imaging, and artificial intelligence enables a deeper understanding of tumor morphology and biological behavior through analysis of imaging features, thereby characterizing the heterogeneity inherent in breast cancer. This review explores MRI’s role as an imaging biomarker for evaluating breast cancer molecular subtypes, aiming to support personalized treatment strategies and improve therapeutic outcomes.

OBJECTIVE:Intratumoral heterogeneity may limit the representativeness of biopsy-based Ki-67 assessment in breast cancer. We therefore developed and validated a habitat-guided 2.5D deep learning (DL) model based on multiparametric MRI for noninvasive preoperative prediction of high versus low Ki-67 expression. METHODS:This retrospective study enrolled 333 patients with invasive breast carcinoma from 2 distinct MRI vendor cohorts (Siemens, training set, n=233; United Imaging, independent test set, n=100). All patients underwent preoperative multiparametric MRI, including DCE-MRI and DWI. Hemodynamic parametric maps (wash-in, wash-out) and ADC maps were generated and subsequently clustered using a K-means algorithm (k=3) to create a functional habitat mask that quantitatively encodes intratumoral heterogeneity. A 7-channel 2.5D input tensor was then constructed by concatenating the central habitat-guided slice with its 6 adjacent anatomic slices. A ResNet18 backbone was trained to classify high (≥20%) versus low Ki-67 expression. The model's performance was rigorously evaluated against conventional 2D DL, clinical, and combined (DL+clinical) models using AUC, the DeLong test, and decision curve analysis (DCA). RESULTS:In the challenging independent cross-vendor test set, our habitat-guided DL25D model demonstrated superior performance, achieving an AUC of 0.821 (95% CI: 0.736-0.906) and a sensitivity of 0.804. It significantly outperformed both the conventional DL2D model (AUC: 0.654, P=0.002) and the clinical model (AUC: 0.686, P=0.019). The incorporation of clinical variables failed to yield further improvement (combined model AUC: 0.837, P=0.483 vs. DL25D; NRI=0.021, P>0.05). DCA confirmed the superior net clinical benefit of our approach across a wide spectrum of threshold probabilities. Importantly, Grad-CAM visualizations revealed that the habitat-guided model strategically focused its attention on intratumoral core regions, whereas the conventional 2D model was distracted by tumor margins and background tissue. CONCLUSIONS:The habitat-guided 2.5D deep learning model showed potential as a noninvasive imaging adjunct for preoperative Ki-67 status prediction in breast cancer. Multicenter prospective validation is required before clinical use.

BACKGROUND:Esophageal hypersensitivity is an important cause of refractory gastroesophageal reflux disease, in which patients do not respond to standard acid-suppressive therapy and suffer from continuous noncardiac chest pain and regurgitation. The N-methyl-D-aspartate receptor (NMDAR) may play a crucial role in the development of visceral hypersensitivity in functional gastrointestinal disorders. However, the specific mechanisms of visceral hypersensitivity in upper digestive tract diseases remain poorly understood. AIM:To investigate the role of the NMDAR2B/protein kinase A (PKA)/cAMP-response element binding protein (CREB) signaling pathway in the development of esophageal neuropathic pain associated with gastroesophageal reflux disease (GERD). METHODS:Thirty-six 6-week-old specific pathogen free rats were randomly assigned to six groups: the control, model, model + NMDAR agonist, model + NMDAR antagonist, model + PKA antagonist, and model + NMDAR antagonist + PKA agonist groups, with six rats in each group. The model was induced via an intraperitoneal injection of ovalbumin for sensitization along with local esophageal stimulation. Immunohistochemistry and Western blotting were utilized to assess the expression levels of NMDAR2B signaling pathway-related proteins in the cingulate gyrus, dorsal thalamus, spinal dorsal horn, and peripheral esophageal tissues. RT-PCR was used to measure the corresponding mRNA expression, and ELISA was used to determine the serum brain-derived neurotrophic factor (BDNF) concentration. Behavioral scoring was performed during balloon distention and acid perfusion of the lower esophagus. RESULTS:Compared with the control group, the model group presented significantly increased expression levels of the NMDAR2B, PKA, CREB, BDNF, substance P, and calcitonin gene-related peptide proteins and mRNAs in the cingulate gyrus, dorsal thalamus, spinal dorsal horn, and lower esophagus (P < 0.05). Compared with the model group, the model + NMDAR agonist group exhibited even higher expression levels of these proteins and mRNAs (P < 0.05), whereas the model + NMDAR antagonist and model + PKA antagonist groups presented lower expression levels (P < 0.05). The model + NMDAR antagonist + PKA agonist group presented higher expression levels than did the model + NMDAR antagonist group (P < 0.05). The changes in the serum BDNF concentration and behavioral score during balloon distention and acid perfusion were consistent with these changes in expression. CONCLUSION:The NMDAR2B signaling pathway plays a critical role in the development of neuropathic pain in GERD through the PKA/CREB/BDNF pathway.

The systemic immune-inflammation index (SII) may influence bone homeostasis through inflammatory modulation. Although bone marrow adipocytes regulate bone metabolism via adipokine secretion, their interaction with SII remains unexplored. We investigated the SII-marrow adiposity relationship in postmenopausal women. This retrospective study included 187 postmenopausal women. Lumbar spine MRI using chemical shift encoding generated proton density fat fraction (PDFF) maps, with bone mineral density (BMD) measured by dual x-ray absorptiometry. The relationship between SII and marrow PDFF was evaluated through multivariable-adjusted linear regression, smooth curve fittings, and threshold analysis. The results revealed a negative correlation between marrow PDFF values and BMD (r = − 0.438, P < 0.001). After accounting for age, time since menopause, body mass index, physical activity, C-reactive protein, interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and BMD in the regression analysis, each unit increase in SII was found to be inked to an increase of 0.247 (β = 0.247; 95

ObjectiveTo investigate the relationship between the Chinese visceral adiposity index (CVAI) and vertebral proton density fat fraction (PDFF).MethodsThe study included 181 postmenopausal females including 53 normal bone mineral density (BMD), 88 osteopenia, and 40 osteoporosis. Vertebral marrow PDFF was measured using Fat Analysis & Calculation Technique imaging, and BMD was assessed via dual-energy X-ray absorptiometry. Bone turnover biomarkers and lipid metabolism were evaluated. The relationship between CVAI and PDFF was assessed using multivariable linear regression models, generalized additive models, and threshold effect analysis.ResultsThe mean BMD at the lumbar spine increased, and PDFF significantly decreased as quartiles of CVAI increased (P for trends <0.05). Multivariable linear regression analysis revealed a clear negative correlation between CVAI and PDFF (regression coefficient β = −0.251, 95% CI, −0.303 to −0.200; P < 0.001) after adjusting for age, time since menopause, waist circumference, body mass index, physical activity, and lipid profiles. The association with marrow PDFF remained significant (β = −0.202, 95% CI, −0.255 to −0.149, P < 0.001) even after additional adjustment for BMD. Further analysis revealed an L-shaped non-linear relationship between CVAI and marrow PDFF after adjusting for age, time since menopause, waist circumference, body mass index, physical activity, lipid profiles, and BMD. An inflection point was identified at a CVAI of 128.3, below which each one-unit increase in CVAI corresponded to a more substantial decrease in marrow PDFF (β = −0.0055, 95% CI: −0.0064 to −0.0045; P < 0.001). However, above this inflection point, each unit increase in CVAI was not significantly associated with a decrease in marrow PDFF.ConclusionsCVAI exhibited a nonlinear negative association with marrow adiposity within a suitable range, once CVAI crossed a definite threshold, PDFF ceased to increase. This finding suggests that a moderate visceral fat accumulation may enhance skeletal integrity, while excessive visceral fat could potentially have detrimental effects.

Objective:This study aimed to develop MRI-based radiomics machine learning models for predicting adverse pathological prognostic features in prostate cancer and to explore the feasibility of integrating radiomics with clinical characteristics to improve preoperative risk stratification, addressing the limitations of conventional clinical models. Methods:A retrospective cohort of 137 prostate cancer patients between January 2021 and April 2023 with preoperative MRI and postoperative pathology data was divided into adverse-feature-positive (n=85) and negative (n=52) groups. Regions of interest (ROIs) were delineated on ADC and T2WI sequences, and 31 radiomics features were extracted using PyRadiomics. LASSO regression selected optimal features, followed by model construction via five algorithms (logistic regression, decision tree, random forest, SVM, AdaBoost). Clinical models incorporated three variables: biopsy Gleason grade, total PSA, and prostate volume. The best-performing radiomics model was combined with clinical features to build a hybrid model. Model performance was evaluated by AUC, sensitivity, specificity, accuracy, calibration curves, and decision curve analysis (DCA). Results:Patients were randomly split into training (n=95) and validation (n=42) cohorts. The random forest model using ADC-T2WI combined features achieved the highest AUC (0.832; 95% CI: 0.706-0.958) in the validation set, outperforming the clinical model (AUC=0.772). The hybrid model demonstrated superior performance (AUC=0.909; 95% CI: 0.822-0.995), with sensitivity=0.813, specificity=0.885, and accuracy=0.857. Calibration and DCA confirmed its robust clinical utility (p<0.01 vs. single models). Conclusions:The biparametric MRI radiomics-random forest model effectively predicts adverse pathological features in prostate cancer. Integration with clinical characteristics further enhances predictive accuracy, offering a non-invasive tool for preoperative risk stratification and personalized treatment planning.

OBJECTIVE:To investigate the relationship between body roundness index (BRI) and lumbar marrow proton density fat fraction (PDFF) in postmenopausal women, with emphasis on potential nonlinear associations. METHODS:In this retrospective cross-sectional study of 186 postmenopausal women, lumbar PDFF was quantified using T2-corrected magnetic resonance spectroscopy (L3 vertebra), and bone mineral density (BMD) was assessed via dual-energy X-ray absorptiometry. Multivariable-adjusted linear regression and nonlinear analyses (smooth curve fitting, two-segment linear models) were employed to evaluate BRI-PDFF relationships, adjusting for age, menopause duration, physical activity, and BMD. RESULTS:Both BRI and lumbar BMD exhibited significant inverse correlations with PDFF (BRI: r = -0.513; BMD: r = -0.462; both P < 0.001). Higher BRI quartiles were associated with elevated BMD at total hip, femoral neck, and lumbar spine (P < 0.05, Q4 vs. Q1-Q3) and a progressive reduction in adjusted PDFF (Ptrend < 0.05). Linear regression confirmed dose-dependent inverse associations between BRI (continuous/quartile) and PDFF (adjusted β = -1.870 to -11.098, P < 0.05 for Q3-Q4 vs. Q1; Ptrend < 0.001). Nonlinear analysis identified a threshold at BRI = 2.58: below this point, BRI strongly predicted PDFF reduction (β = -26.048, P < 0.001), whereas the association attenuated above it (β = -1.086, P = 0.024). CONCLUSIONS:Increased BRI independently correlates with reduced marrow adiposity in postmenopausal women, with a nonlinear threshold effect (BRI = 2.58) suggesting distinct biological mechanisms at lower versus higher adiposity levels. These findings highlight BRI as a potential biomarker for marrow fat dynamics and a target for metabolic bone disease interventions.

Knee Osteoarthritis (KOA) entails progressive cartilage degradation, reviewed via MRI for morphology, biochemical composition, and microtissue alterations, discussing clinical advantages, limitations, and research applicability. Compositional MRI, like T2/T2* mapping, T1rho mapping, gagCEST, dGEMRIC, sodium imaging, diffusion-weighted imaging, and diffusion-tensor imaging, provide insights into cartilage injury in KOA. These methods quantitatively measure collagen, glycosaminoglycans, and water content, revealing important information about biochemical compositional and microstructural alterations. Innovative techniques like hybrid multi-dimensional MRI and diffusion-relaxation correlation spectrum imaging show potential in depicting initial cartilage changes at a sub-voxel level. Integration of automated image analysis tools addressed limitations in manual cartilage segmentation, ensuring robust and reproducible assessments of KOA cartilage. Compositional MRI techniques reveal microstructural changes in cartilage. Multi-dimensional MR imaging assesses biochemical alterations in KOA-afflicted cartilage, aiding early degeneration identification. Integrating artificial intelligence enhances cartilage analysis, optimal diagnostic accuracy for early KOA detection and monitoring.

Purpose: To determine whether multiparametric MRI-based spatial habitats and fractal analysis can help distinguish triple-negative breast cancer (TNBC) from non-TNBC. Method: Multiparametric DWI and DCE-MRI at 3T were obtained from 142 biopsy- and surgery-proven breast cancer with 148 breast lesions (TNBC = 26 and non-TNBC = 122). The contrast-enhancing lesions were divided into 3 spatial habitats based on perfusion and diffusion patterns using K-means clustering. The fractal dimension (FD) of the tumour subregions was calculated. The accuracy of the habitat segmentation was measured using the Dice index. Inter- and intra-reader reliability were evaluated with the intraclass correlation coefficient (ICC). The ability to predict TNBC status was assessed using the receiver operating characteristic curve. Results: The Dice index for the whole tumour was 0.81 for inter-reader and 0.88 for intra-reader reliability. The inter- and intra-reader reliability were excellent for all 3 tumour habitats and fractal features (ICC > 0.9). TNBC had a lower hypervascular cellular habitat and higher FD 1 compared to non-TNBC (all P < .001). Multivariate analysis confirmed that hypervascular cellular habitat (OR = 0.88) and FD 1 (OR = 1.35) were independently associated with TNBC (all P < .001) after adjusting for rim enhancement, axillary lymph nodes status, and histological grade. The diagnostic model combining hypervascular cellular habitat and FD 1 showed excellent discriminatory ability for TNBC, with an AUC of 0.951 and an accuracy of 91.9%. Conclusions: The fraction of hypervascular cellular habitat and its FD may serve as useful imaging biomarkers for predicting TNBC status.

ObjectiveTo investigate the relationship between circulating receptor activator of nuclear factor-kappa B ligand (RANKL) levels and marrow adipose tissue in postmenopausal females.MethodsA total of 164 postmenopausal females were included in the study. Serum levels of osteoprotegerin (OPG) and RANKL were measured using ELISA kits. Body composition and bone mineral density (BMD) were assessed using dual-energy X-ray absorptiometry. Complex-based chemical shift imaging-based MRI was employed to evaluate the vertebral marrow proton density fat fraction (PDFF). A multivariate linear regression model was utilized to analyze the predictive effects of PDFF and BMD on circulating levels of OPG and RANKL.ResultsSimple regression analysis showed significant associations among the marrow PDFF, BMD at either site, serum RANKL, and the RANKL/OPG ratio. In multivariate linear regression models, marrow PDFF was found to have a positive correlation (β = 3.15, 95% CI 2.60 to 3.70) and BMD had negative correlations (β = −0.200, 95% CI −0.348 to −0.051 for vertebral BMD; β = −0.383, 95% CI −0.589 to −0.177 for total hip BMD; and β =−0.393, 95% CI −0.598 to −0.188 for femoral neck BMD, all p < 0.01) with circulating soluble RANKL levels after adjusting for age, body mass index, physical activity, total fat mass, android/gynoid ratio, and lean mass. Similar results were observed for the RANKL/OPG ratio. Additionally, multivariate linear regression analyses revealed that marrow PDFF was a significant independent contributor of circulating soluble RANKL (β = 1.34, 95% CI 1.10 to 1.58, p < 0.001) after further controlling for BMD. However, marrow PDFF or BMD had no associations with circulating levels of OPG after adjusting for all potential confounders mentioned above.ConclusionsVertebral marrow fat fraction is independently associated with circulating soluble RANKL levels in postmenopausal females.

背景:血管周围干细胞来源于成体脂肪组织,获取容易且干细胞比较均质,具有较强的增殖和多向分化潜能.目的:通过体外、体内实验探讨人血管周围干细胞的成骨分化能力,以及Wnt/β-catenin信号通路的调控作用.方法:抽脂来源的人脂肪组织,经荧光激活细胞分选法提取血管周围干细胞,第1代血管周围干细胞进行成骨诱导分化,分为空白对照组、成骨诱导组及Wnt信号通路抑制组,成骨诱导第5天行碱性磷酸酶染色,第10天行茜素红染色,第7天通过Western blot检测Runt相关转录因子2蛋白表达.制备血管周围干细胞复合纳米羟基磷灰石/聚乳酸-羟基乙酸共聚物支架材料,通过无胸腺小鼠胫骨单皮质缺损模型,研究血管周围干细胞在体内的骨修复效果.结果 与结论:①每100 mL脂肪中含有基质血管成分细胞为(1.82±0.32)×107,活细胞占(82.72±5.37)％,经荧光激活细胞分选法分选,血管外膜细胞(CD34+、CD45-、CD146-)比例为(17.66±1.05)％、血管外周细胞(CD146+、CD45-、CD34-)比例为(7.18±0.52)％,血管周围干细胞体外扩增迅速,10代之内保持较强的增殖能力;②细胞实验显示血管周围干细胞具有成骨分化能力,抑制Wnt信号通路后Runt相关转录因子2表达明显减少,血管周围干细胞成骨分化受到抑制,动物实验进一步证实血管周围干细胞复合支架材料的成骨效果;③结果 表明:Wnt/β-catenin信号通路在血管周围干细胞成骨分化中发挥重要作用,血管周围干细胞为骨修复提供一种新的治疗选择.

Early OA is subclinical for anatomic change of cartilage, making it difficult for conventional MRI detection. This study is aimed to apply diffusion-relaxation correlation spectrum imaging (DR-CSI) to knee early-stage OA detection. DR-CSI compartment volume fractions VA, VB and VC had correlation with the modified Whole-Organ MR Imaging Scores (WORMS). VC had better ability than VA, VB, VD, T2 and ADC to discriminate early OA patients from healthy controls. The results illustrated that DR-CSI compartment volume fractions may be sensitive indicators for detecting early-stage degeneration in knee articular cartilage.

Background The association between perivascular space (PVS) and white matter hyperintensity (WMH) has been unclear. Normal-appearing white matter (NAWM) around WMH is also found correlated with the development of focal WMH. This study aims to investigate the topological connections among PVS, deep WMH (dWMH) and NAWM around WMH using 7 Tesla (7T) MRI. Methods Thirty-two patients with non-confluent WMHs and 16 subjects without WMHs were recruited from our department and clinic. We compared the PVS burden between patients with and without WMHs using a 5-point scale. Then, the dilatation and the number of PVS within a radius of 1 cm around each dWMH were compared with those of a reference site (without WMH) in the contralateral hemisphere. In this study, we define NAWM as an area within the radius of 1 cm around each dWMH. Furthermore, we assessed the spatial relationship between dWMH and PVS. Results Higher PVS scores in the centrum semiovale were found in patients with >5 dWMHs (median 3) than subjects without dWMH (median 2, p = 0.014). We found there was a greater dilatation and a higher number of PVS in NAWM around dWMH than at the reference sites (p<0.001, p<0.001). In addition, 79.59% of the dWMHs were spatially connected with PVS. Conclusion dWMH, NAWM surrounding WMH and MRI-visible PVS are spatially correlated in the early stage of cerebral small vessel disease. Future study of WMH and NAWM should not overlook MRI-visible PVS.

Bone marrow adipose tissue has brown fat characteristics. Several studies have demonstrated that total flavonoids of Epimedium (TFE) could prevent bone loss and reduce the white adiposity in bone marrow induced by ovariectomy (OVX) in rats. However, the effects of TFE on marrow brown fat in OVX rats remain unclear. In this word, we addressed this question expected to provide a new target for preventing and treating osteoporosis. Thirty-six 3-month-old female Sprague-Dawley rats were equally divided into Sham controls, OVX controls, and OVX treated with TFE. Chemical shift coding magnetic resonance was performed to detect marrow fat fraction at the left femur at baseline, 6 and 12 weeks post-OVX. Bone mineral density at the lumbar spine and femur was measured by dual-energy x-ray absorptiometry. Serum bone biomarkers by ELISA, trabecular bone microarchitecture at the proximal tibia by micro-CT, quantitative parameters of marrow adipocyte by hematoxylin, and eosin staining were evaluated. The marrow adipocyte gene and protein expressions profile were determined by real-time quantitative PCR and immunostaining in whole tibiae. We found that TFE treatment could decrease bone turnover rate and improved bone mineral density and trabecular microarchitecture in OVX rats. OVX resulted in marrow adipogenesis as evidenced by increased marrow fat fraction, larger marrow adipocyte size, increased adipocyte number and percentage of adipocyte area, marrow white adipocyte gene, and protein expression, including PPARγ2 and FABP4. These pathological changes induced by estrogen deficiency were restored by TFE treatment. TFE also increased brown adipocyte expressions of the transcription factor Ucp1 and Prdm16 in whole tibiae. There was no detectible protein expression of brown adipocyte markers in the proximal tibia. Taken together, TFE regulation of bone marrow adiposity in OVX rats is mediated, at least in part, via maintaining the reciprocity of white and brown adipose tissue.

ObjectiveThis study aimed to investigate brain plasticity by somatosensory stimulation (SS) and sensory observation (SO) based on mirror neuron and embodied cognition theory. Action observation therapy has been widely adopted for motor function improvement in post-stroke patients. However, it is uncertain whether the SO approach can also contribute to the recovery of sensorimotor function after stroke. In this study, we explored the therapeutic potential of SO for sensorimotor dysfunction and provided new evidence for neurorehabilitation.MethodsTwenty-six healthy right-handed adults (12 men and 14 women), aged 18–27 (mean, 22.12; SD, 2.12) years were included. All subjects were evaluated with task-based functional magnetic resonance imaging (fMRI) to discover the characteristics and differences in brain activation between SO and SS. We adopted a block design with two conditions during fMRI scanning: observing a sensory video of brushing (task condition A, defined as SO) and brushing subjects' right forearms while they watched a nonsense string (task condition B, defined as SS). One-sample t-tests were performed to identify brain regions and voxels activated for each task condition. A paired-sample t-test and conjunction analysis were performed to explore the differences and similarities between SO and SS.ResultsThe task-based fMRI showed that the bilateral postcentral gyrus, left precentral gyrus, bilateral middle temporal gyrus, right supramarginal gyrus, and left supplementary motor area were significantly activated during SO or SS. In addition to these brain regions, SO could also activate areas containing mirror neurons, like the left inferior parietal gyrus.ConclusionSO could activate mirror neurons and sensorimotor network-related brain regions in healthy subjects like SS. Therefore, SO may be a promising novel therapeutic approach for sensorimotor dysfunction recovery in post-stroke patients.