Fat Infiltration Research Articles

Cold-Pressed Aristotelia chilensis (Mol.) Stuntz Seed Oil Prevents Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) in a High-Fat-Diet-Induced Obesity Murine Model

This study evaluated the effects of cold-pressed maqui (Aristotelia chilensis (Mol.) Stuntz) seed oil (MO) on liver metabolism and biochemical markers in a high-fat diet (HFD) murine model. In it, the fatty acid profile, tocopherol and tocotrienol contents, and antioxidant capacity of MO were analyzed. Male C57BL/6 mice were divided into four groups (i.e., a, b, c, and d groups) and supplemented for 12 weeks according to the following distribution: (a) control diet (CD)-sunflower oil (SO), (b) CD+MO, (c) HFD+SO, and (d) HFD+MO. Total body and organ weights, serum markers, and liver fat infiltration were assessed. MO contained 32.31% oleic acid, 46.41% linoleic acid, and 10.83% α-linolenic acid; additionally, α- and γ-tocopherol levels were 339.09 ± 5.15 and 135.52 ± 38.03 mg/kg, respectively, while β-, δ-tocopherol, and α-tocotrienol were present in trace amounts and the antioxidant capacity measured was 6.66 ± 0.19 μmol Trolox equivalent/g. MO supplementation significantly reduced the visceral fat (0.76 ± 0.06 g vs. 1.32 ± 0.04 g) and GPT (glutamate pyruvate transaminase) levels (71.8 ± 5.0 vs. 35.2 ± 2.6 U/L), and the liver fat infiltration score (6 vs. 3) in the HFD+MO group compared to HFD+SO. It is suggested that MO may effectively prevent fatty liver disease, warranting further research on its potential benefits for human health.

The effect of lumbar multifidus muscle degeneration on upper lumbar disc herniation

PurposeThis study aimed to investigate the effect of lumbar multifidus muscle (MF) degeneration on upper lumbar disc herniation (ULDH).MethodsThis study used 3.0T magnetic resonance imaging (MRI) T2 axial weighted images to retrospectively analyze 93 ULDH patients and 111 healthy participants. Sixty-five pairs of participants were included in this study using propensity score matching (PSM). Cross-sectional area, fat infiltration area, anteroposterior diameter (APD), lateral diameter (LD), cross-sectional area of the bilateral multifidus muscles at the corresponding level, intervertebral disc area at the corresponding section, and visual analog scale (VAS) score for low back pain (LBP). For inter-group comparisons, we used the t-test, analysis of variance (ANOVA), Mann–Whitney U test, Kruskal–Wallis test, chi-square test, or Fisher's exact test, according to the type of data. We used Pearson correlation analysis to study the correlation between the VAS score and related indicators, and established a predictive model for upper lumbar disc herniation using the receive operative characteristic (ROC) curve analysis method. Finally, univariate and multivariate logistic regression analyses were performed to establish a predictive model for the risk of high lumbar disc herniation.ResultsWe compared the fat areas at the lumbar vertebral levels L1/2, L2/3, and L3/4, as well as the left lateral diameter (LD) (MF), L1/2 left lumbar multifidus muscle index (LMFI), and L1/2 total fat infiltration cross-section area (TFCSA), and found significant differences between the case and control groups (P < 0.001). Furthermore, we observed a significant positive correlation (P < 0.05) between the VAS scores and multiple muscle indicators. Additionally, we developed ROC prediction models to assess the risk of lumbar intervertebral disc protrusion at the L1/2, L2/3, and L3/4 levels, with the results identifying L1/2 TFCSA, L2/3 TFCSA, and L3/4 relative psoas major muscle cross-section area (rPMCSA) as the most predictive indicators. Finally, univariate and multivariate logistic regression analyses showed that the L1/2 rPMCSA, L2/3 TFCSA were significantly associated with the risk of lumbar intervertebral disc protrusion in both models.ConclusionDegeneration of the MF is significantly correlated with the occurrence of ULDH, and the larger the area of fat infiltration in the MF, the more obvious the lower back pain in ULDH patients. In addition, TFCSA can serve as an indicator of the occurrence of ULDH.

Efficacy of acupuncture for lumbar disc herniation: changes in paravertebral muscle and fat infiltration – a multicenter retrospective cohort study

ObjectiveThis study seeks to elucidate the dynamic alterations in the multifidus, erector spinae, and psoas major muscles, along with their fatty infiltration, in patients diagnosed with lumbar disc herniation treated through acupuncture. Concurrently, the Visual Analogue Scale (VAS) and Japanese Orthopedic Association (JOA) scores are employed to evaluate modifications in lumbar and leg pain and the enhancement in lumbar functionality.MethodsA retrospective multi-center cohort study enrolled 332 adult LDH patients. Participants were divided into acupuncture and rehabilitation therapy groups. The acupuncture cohort received targeted treatments at specific acupuncture points, while the rehabilitation group received traditional rehabilitative therapy. Magnetic Resonance Imaging (MRI) gauged muscle cross-sectional areas (Sm, Se, Sp) and their ratios to vertebral area (Sm/Sv, Se/Sv, Sp/Sv), and fatty infiltration areas (Sfm, Sfe, Sfp) and their ratios (Sfm/Sv, Sfe/Sv, Sfp/Sv). Pain and function were assessed using Visual Analogue Scale (VAS) and Japanese Orthopedic Association (JOA) scores pre-treatment, 2-weeks, and 3-months post-intervention.ResultsA total of 332 patients were enrolled for analysis. Post-treatment, the acupuncture group exhibited increased Sm, Se, Sp and their ratios and reduced fatty infiltration areas and their ratios (P<0.05) compared to rehabilitation. Both treatments decreased VAS scores and enhanced JOA scores at both intervals (P<0.05). Intriguingly, no significant disparities were observed between the acupuncture and rehabilitation groups concerning pain and JOA scores at the 2-week follow-up (p>0.05); however, 3 months post-treatment, the acupuncture group significantly outperformed the rehabilitation group in both pain and JOA scores (p<0.05).ConclusionThis study demonstrates that acupuncture treatment is significantly more effective than traditional rehabilitation therapy in improving paraspinal muscle function, reducing muscle fat infiltration, and alleviating lumbar and leg pain in patients with lumbar disc herniation (LDH). Specifically, acupuncture significantly increases the cross-sectional areas (Sm, Se, Sp) of the paraspinal muscles and reduces muscle fat infiltration, showing superior long-term results in pain relief and functional improvement. Future research should further explore the long-term effects of acupuncture on the function and structure of paraspinal muscles, assess its potential in preventing the recurrence of LDH, and delve deeper into how acupuncture affects paraspinal muscles at the molecular level, to better understand its therapeutic mechanisms and enhance its clinical application.

Biotoxicity Evaluation of Biodegradable Polymeric Particles: Exploring the Possible Adverse Impacts on Biological Systems

ABSTRACTThis study aimed to investigate the impact of plastic particles on cell viability and tissue toxicity. The cells were subjected to incubation with plastic particles immobilized in agar gels, resulting in minimal cell death and cytotoxicity. Furthermore, direct exposure of various cell types to suspended plastic particles showed negligible effects on cell viability, with no observed lysis or growth inhibition. Staining techniques revealed minimal plastic particle‐induced cell death, with the majority of cells remaining viable. However, histological evaluations of mouse tissues demonstrated that the nondegradable low‐density poly(ethylene) (LDPE) groups exhibited severe irritation, characterized by an excessive presence of macrophages, neutrophils, fibrosis, fat infiltration, and increased blood vessel formation in subcutaneous tissue. In contrast, biodegradable neat poly(butylene succinate) (KRICT‐PBS) and cellulose nanocrystals/PBS nanocomposite (CNC‐PBS) groups induced minimal toxicity. Interestingly, the intravenous injection of KRICT‐PBS and CNC‐PBS degradate solutions in mice exhibited mild toxicity, suggesting no significant damage to normal kidney and liver function.

Short-chain fatty acids enhance muscle mass and function through the activation of mTOR signalling pathways in sarcopenic mice.

Sarcopenia is a prevalent muscle disorder in old people leading to higher fracture rate, mortality, and other adverse clinical outcomes. Evidence indicates that short-chain fatty acids (SCFAs), which are beneficial gut microbial metabolites, were reduced in old people with sarcopenia. This study aimed to determine whether the use of SCFAs as a supplement can be a therapeutic strategy of sarcopenia in a pre-clinical model. Seven-month-old pre-sarcopenic senescent accelerated mouse prone 8 (SAMP8) mice received daily SCFAs cocktail (acetate, butyrate, and propionate) for 3months. Age-matched senescence accelerated mouse resistant 1 (SAMR1) and SAMP8 mice receiving sodium-matched drinking water were control groups. The gut microbiota composition analysis of aged mice with or without sarcopenia was conducted by 16S rDNA sequencing. Gut barrier-related proteins and lipopolysaccharide (LPS) concentration were biomarkers of gut permeability. Colon inflammation levels, circulatory SCFAs concentration, muscle quality, function, and underlying pathways were detected by cell number counting, RT-qPCR, gas chromatography-mass spectrometry, measurements of muscle wet weight and grip strength, ex vivo functional test, treadmill endurance test, transcriptomic sequencing, morphological and immunofluorescent staining, as well as western blot. To investigate the role of mTOR signalling pathways in SCFAs treatment, C2C12 myotubes were treated with rapamycin. Aged SAMP8 mice had different microbiota composition, and lower serum butyric acid compared with SAMR1 mice (P<0.05). SCFAs treatment reversed the increment of colon inflammation (2.8-fold lower of il-1β) and gut barrier permeability (1.7-fold lower of LPS) in SAMP8 mice. Increased muscle mass, myofibre cross-sectional area, grip strength, twitch and tetanic force were found in SCFAs-treated mice compared with control SAMP8 mice (P<0.05). Anti-fatigue capacity (1.6-fold) and muscle glycogen (2-fold) also improved after SCFAs treatment (P<0.05). Transcriptomic analysis showed that AMPK, insulin, and mTOR pathways were involved in SCFAs treatment (P<0.05). Regulation of AKT/mTOR/S6K1 and AMPK/PGC1α pathways were found. SCFAs attenuated fat infiltration and improved mitochondria biogenesis of atrophic muscle. In vitro studies indicated that SCFAs inhibited FoxO3a/Atrogin1 and activated mTOR pathways to improve myotube growth (P<0.05), and rapamycin attenuated the effect of SCFAs through the inhibition of mTOR pathways. This study demonstrated that bacterial metabolites SCFAs could attenuate age-related muscle loss and dysfunction, and protein synthesis-related mTOR signalling pathways were involved both in vivo and in vitro.

Unilateral biportal endoscopic vs. open surgery in the treatment of young obese patients’ lumbar degenerative diseases: a retrospective study

BackgroundObesity accelerates the development of lumbar disease and increase the risk during surgery. Unilateral biportal endoscopic discectomy (UBE) is a newly developed minimally invasive technique, which refers to the spinal surgery under unilateral double-channel endoscopic surgery. Therefore, the purpose of this study is whether UBE decompression alone can bring good clinical results to young obese patients with lumbar degenerative diseases.MethodsThe patients with lumbar diseases who underwent UBE and open surgery (open discectomy) in our hospital from February 2020 to February 2022 were selected as young (age ≤ 44 years old) and obesity (BMI ≥ 30 kg/m2). The patients were evaluated with VAS, ODI, JOA and modified Macnab score before operation, 1 month, 6 months and 12 months after operation. Nerve root function sensation, muscle strength and tendon reflex were evaluated. The operation time, estimated blood loss, postoperative hospital stay, incidence of postoperative complications and reoperation rate were recorded. MRI quantitative lumbar multifidus muscle (LMM) comparison was performed 12 months after operation.Results77 patients were included, and the scores of VAS, ODI and JOA were similar in the two groups during the last follow-up. There were no difference in nerve root function sensation, muscle strength or tendon reflex. However, one month after operation, the VAS back score and ODI improvement in the UBE group were significantly better than those in the open group, which were 2.44 ± 0.97, 33.10 ± 6.78 and 2.93 ± 0.79 and 36.13 ± 5.84, respectively, with a statistically significant difference (p = 0.020 and 0.038). According to the modified Macnab criteria, UBE group, the excellent and good rate was 97.2%. The excellent and good rate of open group was 97.6%. The estimated blood loss and postoperative hospital stay in UBE group (36.81 ± 17.81, 3.92 ± 1.32) were significantly better than those in open group (104.88 ± 31.41, 6.41 ± 1.94), with a statistically significant difference (p = 0.010). There was no significant difference in operation time between the two groups (p = 0.070). The number of complications in UBE group was 2 (5.6%) and open group was 4 (9.8%). The fat infiltration rate of 19.3%+11.0% in UBE group was significantly lower than that of 27.0%±13.9% in open group (p = 0.010).ConclusionUBE has the advantage of early recovery in the treatment of lumbar degenerative diseases in young obese patients, and reduces the damage to LMM, so it has a good clinical effect.

The assessment of myopenia and muscle biopsy in pediatric patients with liver disease awaiting liver transplantation – A cross-sectional analysis

Little is known about the skeletal muscle characteristics (fibre type proportion and size, location of nuclei, presence of fat infiltration) in children with liver disease with radiologically determined myopenia (low muscle mass). During liver transplantation (LTx) surgery, biopsies from the rectus abdominis muscle were collected. Muscle fibre types (I, I/IIA, IIA, IIA/X, IIX) and CSA index (µm/m2) were determined using immunofluorescence staining. Triacylglycerol (TAG) and phospholipid content of muscle was determined using gas chromatography. Myopenia was defined using study-specific cut offs (skeletal muscle index &lt;-2SD) from age-sex matched healthy control scans. Myopenia was prevalent in 41% of children. Children also had a high prevalence of high muscle adiposity (37%). Children with myopenia were older (8.4 vs. 0.7 yrs; p&lt;0.001), had smaller total (median 595 vs. 844 µm/m2; p=0.04) and hybrid IIA/X (612±143 vs. 993±341 µm/m2; p=0.04) muscle fibre size index, lower prevalence of type I fibres (53 vs. 64%; p=0.01) and higher prevalence of type IIA/X hybrid fibres (median 7.5 vs. 0%; p=0.04). Children with myopenia also had a higher prevalence of elevated TAG content (&gt;75 percentile) within the muscle compared to children without myopenia (36% vs 0%; p=0.009). Percent of muscle fibres with centralized nuclei were not different between groups. In conclusion, children with myopenia experience differences in skeletal muscle biological characteristics when compared to children without myopenia at LTx and these findings may have implications for dietary and exercise rehabilitation pre-and post-LTx.

Liver Fibrosis Index-4 Does Not Correlate to Liver Elastography in Patients with Inflammatory Bowel Disease

Background: Inflammatory bowel disease (IBD) is associated with an increased prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD). The Fibrosis-4 (FIB-4) index is a non-invasive tool for assessing liver fibrosis that has been validated in various liver diseases. The main objective of this study was to study whether the FIB-4 index is a reliable predictor of liver fibrosis, as assessed through elastography, in patients with IBD. We additionally aimed to analyze if FIB-4 associates with IBD characteristics such as lipid profile, subclinical carotid atherosclerosis, and insulin resistance indices. Methods: A cross-sectional study was conducted, enrolling 197 patients with IBD. Subjects underwent comprehensive clinical and laboratory evaluations. Hepatic fibrosis was assessed non-invasively using the FIB-4 index and transient elastography, while abdominal ultrasonography was performed to grade hepatic steatosis based on the degree of fat infiltration. To investigate the associations between disease characteristics and FIB-4 score and the correlation of this index to elastography, a multivariable linear regression analysis was conducted. Results: The presence of diabetes, hypertension, and metabolic syndrome was associated with significantly higher FIB-4 levels. However, FIB-4 did not show a relationship with disease characteristics such as phenotype or activity indices. Furthermore, FIB-4 did not demonstrate a correlation with liver stiffness values measured by elastography. Conclusions: Our findings suggest that the FIB-4 index may not be a reliable tool for assessing hepatic fibrosis in patients with IBD. This observation is particularly significant given the high prevalence of MASLD in the IBD population.

Skeletal muscle size and quality in healthy kidney donors, normal range and clinical associations

The gold standard to estimate muscle mass and quality is computed tomography (CT) scan. Lower mass and density (intramuscular fat infiltration) of skeletal muscles are markers of sarcopenia, associated with increased mortality risk, impaired physical function, and poorer prognosis across various populations and medical conditions. We aimed to describe standard reference values in healthy population, prospective kidney donors, and correlate clinical parameters to muscle mass and density. Included in the cohort 384 consecutive kidney donors. Mean age was 44.6 ± 11.5 (range 18.4–74.2), 46% were female and mean BMI was 25.6 ± 3.8 kg/m2. Our quantified reference values for psoas cross -sectional area (CSA) index at L3 level (males/females respectively) were 6.3 ± 1.8 and 4.8 ± 1.9 cm2 /m2, and density was 46.1 ± 5 and 41 ± 5 HU at that level. Older age (standardized beta coefficient − 0.12, p = 0.04), sex (− 0.32, p < 0.001) and BMI (0.17, p = 0.002) were significantly associated with CSA index of psoas at L3. Density, however, was associated with triglycerides level (− 0.21, p < 0.001), in addition to age (− 0.22, p < 0.0001), sex (− 0.27, p < 0.001) and BMI (− 0.1, p = 0.05). Our study validates the normative values of psoas muscle mass and density in healthy individuals and suggests correlations with clinical parameters. We demonstrate the significance of measuring not only the mass of the muscle, but also its density, as it has a valid association with metabolic parameters, including BMI and lipid level, even in healthy individuals and in the normal range of the tests.

A comparative analysis of lumbar paraspinal muscle morphology between two movement system impairment subgroups of chronic nonspecific low back pain

BackgroundBased on the kinesiopathologic model, the Movement System Impairment (MSI) classification of LBP has shown that repetitive movements could contribute to pathoanatomic tissue changes. However, these changes have not been evaluated in different MSI classification subgroups of patients with LBP. ObjectiveThis study compared the grades of fatty infiltration as one of the muscle's pathologic changes in the lower lumbar paraspinal and psoas muscles between the two subgroups of patients diagnosed with MSI syndromes having opposite movement direction impairments. DesignObservational cross-sectional study. MethodForty-five participants with chronic LBP were enrolled in the study, with 23 patients in the lumbar flexion-rotation (FlexRot) subgroup and 22 in the lumbar extension-rotation (ExtRot) subgroup of MSI. Magnetic resonance imaging (MRI) and the Goutallier Classification System (GCS) were used for fatty grading of lumbar paraspinal and psoas muscles. After the reliability of this grading scale was evaluated, the results were compared between the two subgroups. ResultsThe Mann–Whitney U Test showed significantly higher fat infiltration of lower lumbar multifidus and erector spinae muscles in the lumbar ExtRot subgroup, with no significant difference between the two subgroups in terms of psoas muscles (P ≤ 0.05). Inter-rater reliability of GCS was acceptable to excellent, and intra-rater reliability was good to excellent. ConclusionThe fatty infiltration grade of lumbar paraspinal muscles in L4-L5 and L5-S1 levels are significantly different between the two LBP subgroups of MSI that have two opposite movement direction impairments. The lumbar paraspinal muscles, which contribute to extension, have a higher grade of fat in the ExtRot subgroup, whose symptoms are aggravated by lumbar extension.

Age-Related Association Between Unilateral Single-Channel and Double-Channel Surgery and Postoperative Multifidus Muscle Atrophy and Fat Infiltration.

Unilateral biportal endoscopic laminotomy (UBE) and percutaneous endoscopic laminotomy (PEL) are minimally invasive spinal surgery (MISS) techniques used for unilateral and dual-channel endoscopic laminectomy. However, limited research has been conducted on lumbosacral multifidus muscle injuries in elderly individuals undergoing MISS for lumbar spinal canal stenosis. The objective of this study was to investigate the impact of single-channel and double-channel MISS on the multifidus muscle in elderly patients. A total of 107 patients who underwent MISS were stratified into two cohorts: group A (<65 years) and group B (≥65 years). Preoperative imaging data, including magnetic resonance imaging, were gathered to classify the degree of stenosis based on the nerve root compression. The extent of multifidus muscle atrophy and fat infiltration was assessed by calculating the fat-free cross-sectional area (FCSA)/cross-sectional area (CSA) ratio before and after surgery through measurements of CSA and FCSA. Total cross-sectional area/FCSA were calculated using MRI cross-sectional T2WI. The degree of atrophy and fat infiltration did not change between procedures in group A (P>.05), but changed significantly in group B (P<.05). Unilateral single-channel and double-channel surgery had no significant effect on the degree of multifidus muscle atrophy and fat infiltration in patients younger than 65 years. However, in patients 65 years and older, the degree of multifidus muscle atrophy and fat infiltration significantly increased with the increasing incidence of lateral recess stenosis, which was positively correlated with the duration of surgery. [Orthopedics. 202x;4x(x):xx-xx.].

Associations of body composition measures with circulating insulin-like growth factor-I, testosterone, and sex hormone-binding globulin concentrations in 16,000 men.

Adiposity is positively associated with risk of some cancer sites and other health conditions in men; however, it is unclear if endogenous hormones play a role in these associations. We examined how body composition, measured from magnetic resonance imaging (MRI) and common measures of adiposity (e.g., body mass index (BMI)), are related to hormone concentrations in men from the UK Biobank study. Up to 16,237 men with available body composition data (including visceral, subcutaneous, and liver fat, muscle fat infiltration (MFI), lean tissue, and common adiposity measures) and serum hormone measurements (insulin-like growth factor-I (IGF-I), total testosterone, sex hormone-binding globulin (SHBG), and calculated free testosterone) were included. Multivariable-adjusted linear regression models were used to determine the geometric mean hormone and SHBG concentrations across categories of each exposure. Common measurements of adiposity were highly correlated with MRI measures of central and total adiposity (r = 0.76-0.91), although correlations with ectopic fat (liver fat and MFI) were lower (r = 0.43-0.54). Most adiposity measurements showed an inverse U- or J-shaped association with circulating IGF-I and free testosterone; however, MFI was linearly inversely associated, and lean tissue volume was positively associated with both IGF-I and free testosterone concentrations. All body composition measures were inversely associated with total testosterone and SHBG concentrations (relative geometric mean difference between Q5 vs. Q1: 20-30%). Our results show that common adiposity and most MRI measures of adiposity relate similarly to serum hormone concentrations; however, associations with ectopic fat (particularly MFI) and lean tissue were different.

Overexpression of ALDOC Promotes Porcine Intramuscular and Intermuscular Fat Deposition by Activating the AKT-mTORC1 Signaling Pathway.

Skeletal muscle fat accumulation, a common complication of obesity, has garnered increasing attention. For livestock animals, intramuscular fat content is a key determinant of meat quality and directly influences consumer preferences for different meat products. However, genes effectively regulating intramuscular and intermuscular fat (IIMF) deposition remain largely unexplored. To address this gap, we employed transcriptome sequencing of muscle from pigs with high and low IIMF contents, uncovering Aldolase C (ALDOC) as a novel key gene controlling IIMF. ALDOC overexpression significantly enhanced the IIMF content both in vivo and in vitro. Mechanistic investigations revealed that ALDOC activates the AKT-mTORC1 axis to promote lipid accumulation in myotubes and intramuscular adipocytes. Notably, the mTORC1 inhibitor rapamycin abrogated ALDOC's proadipogenic effect. Our findings establish ALDOC as a novel key gene regulating IIMF deposition and identify the ALDOC-AKT-mTORC1 signaling pathway as a promising therapeutic target for treating skeletal muscle fat infiltration and improving pork quality.

Muscle Mass and Glucagon-Like Peptide-1 Receptor Agonists: Adaptive or Maladaptive Response to Weight Loss?

Recent studies have shown that pharmacologic weight loss with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and combination therapies is approaching magnitudes achieved with surgery. However, as more weight loss is achieved, there is concern for potential adverse effects on muscle quantity, composition, and function. This primer aims to address whether muscle-related changes associated with weight loss treatments such as GLP-1 RAs may be maladaptive (ie, adversely affecting muscle health or function), adaptive (ie, a physiologic response to weight loss maintaining or minimally affecting muscle health or function), or perhaps an enhanced response to weight loss (ie, improved muscle health or function after treatment). Based on contemporary evidence with the addition of studies using magnetic resonance imaging, skeletal muscle changes with GLP-1 RA treatments appear to be adaptive: changes in muscle volume z-score indicate a change in muscle volume that is commensurate with what is expected given aging, disease status, and weight loss achieved, and the improvement in insulin sensitivity and muscle fat infiltration likely contributes to an adaptive process with improved muscle quality, lowering the probability for loss in strength and function. Nevertheless, factors such as older age and prefrailty may influence the selection of appropriate candidates for these therapies because of risk for sarcopenia. Several pharmacologic treatments to maintain or improve muscle mass designed in combination with GLP-1-based therapies are under development. For future development of GLP-1-based therapies (and other therapies) designed for weight loss, as well as for patient-centered treatment optimization, the introduction of more objective and comprehensive ways of assessing muscle health (including accurate and meaningful assessments of muscle quantity, composition, function, mobility, and strength) is important for the substantial numbers of patients who will likely be taking these medications well into the future.

Sex differences in the relationship between body composition and cardiac structure and function.

The purpose of this study was to characterize sex differences in the relationship between body composition and cardiac structure and function. In secondary analyses, we explored pathophysiologic mediators of these relationships. In a cross-sectional analysis of 25,063 UK Biobank participants (54% female, median age 55 years), the sex-specific associations of visceral adipose tissue volume (VAT), appendicular lean mass (ALM), and muscle fat infiltration (MFI) with cardiac magnetic resonance (CMR) measures of cardiac structure and function were assessed using linear regression models. Using causal mediation analysis, 10 biomarkers were explored as mediators of the relationship between adipose depots and cardiac parameters. VAT was associated with increased left ventricular mass (LVM; βwomen = 0.54, βmen = 0.00, pint = 0.01) and wall thickness (βwomen = 0.12, βmen = 0.08, pint<0.001) in women only. A similar sex-specific pattern was observed for MFI effects on LVM (βwomen = 0.44, βmen = 0.03, pint<0.001). ALM was associated with increased LVM and LV volumes in both women and men. In mediation analyses, insulin resistance as measured by triglycerides/high density lipoprotein ratio was a potential partial mediator of VAT effects on chamber dimensions. In the largest and most rigorous analyses of body composition and cardiac parameters to date, we demonstrated that VAT is associated with increased LVM and wall thickness in women but not in men. MFI association with cardiac parameters was similar to VAT, significant in women but not in men.

Lumbar localized fat distribution parameters are independent predictors of osteoporotic vertebral compression re-fractures (OVCRFs) following Percutaneous Kyphoplasty (PKP): a retrospective matched case-control study.

To investigate potential risk factors for osteoporotic vertebral compression re-fractures (OVCRFs) following percutaneous kyphoplasty (PKP). Patients who underwent PKP from January 2012 to January 2020 were included in this study within the same institution. Cases were defined as patients who experienced OVCRFs, while controls were matched based on corresponding clinical characteristics from those patients without OVCRFs. The lumbar localized fat distribution parameters, including the fat infiltration ratio (FIR) in muscles [multifidus (MF), erector spinae (ES), paravertebral muscles (PVM), and psoas major (PS)] and subcutaneous fat thickness (SFT), were compared between the two groups through radiological data. And other clinical data that may be relevant were also compared. Independent risk factors for OVCRFs after PKP were identified through a binary logistic regression analysis. A total of 1391 patients who underwent PKP were included in this study. 51 patients were categorized into the re-fracture group, and 102 patients were selected as matched controls from the remaining cohort. There were statistically significant differences between the two groups in metrics including MF-FIR, ES-FIR, PVM-FIR, PS-FIR, bone mineral density (BMD), body-mass index (BMI), SFT, hemoglobin (Hb), albumin (ALB), alkaline phosphatase (ALP), and triglycerides (TG) (P < 0.05). Binary logistic regression analysis demonstrated that PVM-FIR (P = 0.003), SFT (P < 0.001), BMD (P = 0.011), and ALP (P = 0.005) were independent predictors for the occurrence of OVCRFs. This study discovered that lumbar localized fat distribution parameters including PVM-FIR and SFT are independent predictors of OVCRFs. Additionally, BMD and ALP were found to be independent predictors of OVCRFs.

Sex Differences in Fat Distribution and Muscle Fat Infiltration in the Lower Extremity: A Retrospective Diverse-Ethnicity 7T MRI Study in a Research Institute Setting in the USA.

Background: Fat infiltration in skeletal muscle is related to declining muscle strength, whereas excess subcutaneous fat is implicated in the development of metabolic diseases. Methods: Using multi-slice axial T2-weighted (T2w) MR images, this retrospective study characterized muscle fat infiltration (MFI) and fat distribution in the lower extremity of 107 subjects (64M/43F, age 11-79 years) with diverse ethnicities (including White, Black, Latino, and Asian subjects). Results: MRI data analysis shows that MFI, evaluated by the relative intensities of the pixel histogram profile in the calf muscle, tends to increase with both age and BMI. However, statistical significance was found only for the age correlation in women (p < 0.002), and the BMI correlation in men (p = 0.04). Sex disparities were also seen in the fat distribution, which was assessed according to subcutaneous fat thickness (SFT) and the fibula bone marrow cross-sectional area (BMA). SFT tends to decrease with age in men (p < 0.01), whereas SFT tends to increase with BMI only in women (p < 0.01). In contrast, BMA tends to increase with age in women (p < 0.01) and with BMI in men (p = 0.04). Additionally, MFI is positively correlated with BMA but not with SFT, suggesting that compromised bone structure may contribute to fat infiltration in the surrounding skeletal muscle. Conclusions: The findings of this study highlight a sex factor affecting MFI and fat distribution, which may offer valuable insights into effective strategies to prevent and treat MFI in women versus men.

Body composition and muscle composition phenotypes in patients on waitlist and shortly after liver transplant – results from a pilot study

BackgroundSarcopenia is common in end-stage liver disease and negatively impacts patients awaiting or undergoing liver transplantation (LT). Magnetic resonance imaging (MRI) may be used to measure body composition and sarcopenia. We aimed to evaluate the feasibility of MRI-based LT body composition profiling, describe waitlist body composition, and assess the natural rate of change in body composition while on the waitlist and post-LT.MethodsThis prospective pilot study recruited adults listed for LT at an urban, tertiary care facility. Eighteen participants were scanned at time of waitlisting and 15 had follow-up MRIs (waitlist and/or post-LT). An 8-min MRI was used to measure body composition (AMRA® Researcher) including thigh fat-free muscle volume (FFMV) and fat infiltration (MFI), visceral (VAT) and abdominal subcutaneous (ASAT) adipose tissue volumes, and liver fat. A sex- and BMI invariant FFMV z-score (z-FFMV) was calculated, and muscle composition (MC) phenotypes were defined using the muscle assessment score (consisting of the FFMV z-score and sex-adjusted MFI). Rate of body composition change was calculated using mixed-effect modelling and is presented as rate per 30 days.ResultsAt time of waitlisting, 73% of the 18 participants had high MFI and 39% had the adverse MC (low FFMV z-score and high MFI) phenotype. Seven participants received an LT. Post-LT serial MRIs, at a median of 147 days apart within the first 200 days post-LT, demonstrated increased z-FFMV 0.22 SDs/(30 days) (p = 0.002), VAT 0.23 (p < 0.001), and ASAT 0.52 (p = 0.001) L/(30 days), but no change in MFI (p = 0.200) nor liver fat (p = 0.232).ConclusionMRI-based body composition profiling is feasible in LT patients and shortly after LT. This can be amended to routine clinical scans and may help in early identification of patients who may benefit from interventions to improve body composition. In addition, body composition changes significantly over time after LT.

The Diagnostic Value of bpMRI in Prostate Cancer: Benefits and Limitations Compared to mpMRI.

Prostate cancer is the second most common cancer in men and a leading cause of death worldwide. Early detection is vital, as it often presents with vague symptoms such as nocturia and poor urinary stream. Diagnostic tools like PSA tests, ultrasound, PET-CT, and mpMRI are essential for prostate cancer management. The PI-RADS system helps assess malignancy risk based on imaging. While mpMRI, which includes T1, T2, DWI, and dynamic contrast-enhanced imaging (DCE), is the standard, bpMRI offers a contrast-free alternative using only T2 and DWI. This reduces costs, acquisition time, and the risk of contrast-related side effects but has limitations in detecting higher-risk PI-RADS 3 and 4 lesions. This study compared bpMRI's diagnostic accuracy to mpMRI, focusing on prostate volume and PI-RADS scoring. Both methods showed strong inter-rater agreement for prostate volume (ICC 0.9963), confirming bpMRI's reliability in this aspect. However, mpMRI detected more complex conditions, such as periprostatic fat infiltration and iliac lymphadenopathy, which bpMRI missed. While bpMRI offers advantages like reduced cost and no contrast use, it is less effective for higher-risk lesions, making mpMRI more comprehensive.

Comparative analysis of functional outcomes in arthroscopic repair for traumatic and non-traumatic rotator cuff injuries

BackgroundThe impact of the etiology of rotator cuff injury (RCI) on outcomes after rotator cuff repair remains unclear. This study aimed to evaluate the postoperative outcomes of patients with RCIs of different etiologies and identify the risk factors affecting prognosis.MethodsThis study included 73 patients with RCI who underwent arthroscopic rotator cuff repair. The patients were categorized into either a traumatic group or a non-traumatic group based on their history of trauma. Preoperative and postoperative assessments included shoulder range of motion, muscle strength, and physical examination findings specific to the shoulder for both groups. Clinical differences between arthroscopic repair of traumatic and non-traumatic RCIs were evaluated using univariate analysis. Logistic regression analysis determined independent risk factors for rotator cuff repair prognosis.ResultsAmong the 73 patients, 31 were in the traumatic group and 42 in the non-traumatic group, with a minimum postoperative follow-up of 12 months and a mean follow-up of 13.8 months. The duration of the disease was significantly longer in the non-traumatic group compared with the traumatic group (P < 0.001). The mean tear area was more significant in the traumatic group than in the non-traumatic group (P = 0.003), and the preoperative pain level and functional scores were better in the non-traumatic group compared with the traumatic group. Postoperatively, there were no differences between the two groups regarding scores, joint mobility, strength, and complications. At 12 months postoperatively, multivariate regression analysis indicated that full-layer tear (OR = 5.106, 95% CI: 1.137–22.927, P = 0.033), fat infiltration (OR = 6.020, 95% CI: 1.113–32.554, P = 0.037), and tear area (OR = 6.038, 95% CI: 2.122–17.177, P < 0.001) significantly affected the University of California at Los Angeles (UCLA) score.ConclusionCompared with non-traumatic RCI, traumatic RCI presents with more pronounced pain and impaired joint function preoperatively yet demonstrates comparable postoperative clinical outcomes. Full-layer tears, fat infiltration, and large tear areas are unfavorable factors affecting rotator cuff repair, and postoperative rehabilitation management of these patients should be emphasized.