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Effects of blood flow restriction training combined with resistance training on lower-limb strength and sport-specific performance in athletes: a systematic review and meta-analysis.

BACKGROUND: In contemporary sports science, athletes and coaches continuously explore strategies to reduce training load and injury risk while increasing muscular strength and sport-specific performance. This meta-analysis evaluated the effects of blood flow restriction training (BFRT) combined with resistance training (RT) on lower-limb muscle strength and sport-specific performance in athletes. METHODS: Relevant randomized controlled trials (RCTs) were systematically searched across major databases (e.g. PubMed, Web of Science, Cochrane, CNKI, Wanfang Data, and Embase) from inception until November 2024. Two independent reviewers carefully assessed the studies. Data analysis was carried out using RevMan 5.4 software, which included heterogeneity testing, meta-analysis, subgroup analysis, and assessment of publication bias. RESULTS: Ten RCTs (181 athletes; 91 in the BFRT and RT group, 90 in the control group) were included. Outcomes determined BFRT combined with RT yielded notable enhancements in lower-limb muscle strength (SMD = 1.09, 95% CI [0.52, 1.66], p&#x2009;<&#x2009;0.05) and muscle hypertrophy (MD = 1.09, 95% CI [0.10, 2.09], p&#x2009;<&#x2009;0.05) compared to control training. However, no significant improvement in sport-specific performance was found (SMD = 0.11, 95% CI [-0.18, 0.40], p&#x2009;=&#x2009;0.46). Substantial heterogeneity was observed for strength outcomes (I2 = 75%), whereas low heterogeneity was observed for sport-specific performance and hypertrophy outcomes (I2 = 0%). No evidence of significant publication bias was detected. CONCLUSION: BFRT combined with RT appears to provide effective augmentation of lower-limb muscle strength and hypertrophy in athletes compared to RT or conventional training alone. It may be prudent to integrate this approach systematically into training cycles to optimize physiological muscle stimulation and training outcomes, despite not directly improving sport-specific performance.

Humans

Effects of essential amino acid supplementation on musculotendinous recovery following eccentric plantar flexor exercise: a randomized controlled trial.

BACKGROUND: Exercise-induced muscle damage (EIMD) resulting from eccentric contractions leads to transient impairments in muscle function. Essential amino acids (EAAs) stimulate muscle protein synthesis and may support recovery following damaging exercise. However, limited research has examined the effects of EAAs on muscle function following eccentric plantar flexor exercise. The purpose of this study was to examine the effects of EAA supplementation on indirect markers of muscle and musculotendinous recovery following EIMD. METHODS: Thirty-six recreationally active males (age: 21.2&#x2009;&#xb1;&#x2009;2.7&#x2009;years) were randomly assigned to an EAA group (10&#x2009;g of EAAs), placebo (10&#x2009;g of maltodextrin), or control (no supplementation). Supplements were consumed 30&#x2009;minutes before and immediately after an eccentric plantar flexor protocol (4&#x2009;&#xd7;&#x2009;50 repetitions followed by one set to failure) and during the 72&#x2009;hours recovery period. Indirect markers of muscle damage were assessed pre-exercise, immediately post-exercise, and 24, 48, and 72&#x2009;hours post-exercise, consisting of perceived soreness (NPRS), pain pressure threshold (PPT), calf muscle thickness and Achilles tendon thickness (ultrasound), and calf circumference. RESULTS: The eccentric protocol elicited responses consistent with EIMD, including increased soreness (p&#x2009;<&#x2009;0.001), increased calf muscle thickness and circumference (p&#x2009;<&#x2009;0.001), and reduced PPT (p&#x2009;=&#x2009;0.018). EAA supplementation attenuated soreness at 24&#x2009;hours compared with placebo. Calf muscle thickness increased following exercise in both groups; however, swelling returned to baseline by 72&#x2009;hours in the EAA group but remained elevated in placebo (Condition&#x2009;&#xd7;&#x2009;Time, p&#x2009;<&#x2009;0.001). Achilles tendon thickness decreased immediately post-exercise (p&#x2009;=&#x2009;0.005) but was not influenced by supplementation. CONCLUSIONS: EAA supplementation modestly reduced soreness and was associated with faster recovery of muscle swelling but did not influence tendon morphology within 72&#x2009;hours.

Humans

Intramuscular Fat Infiltration and Knee Osteoarthritis: A Systematic Review and Meta-Analysis.

BACKGROUND: Intramuscular fat infiltration (IMFI) is considered to be closely associated with knee osteoarthritis (KOA); however, its overall association, muscle-specific involvement, and clinical relevance remain unclear. OBJECTIVE: To quantify the association between IMFI and KOA, identify affected muscle groups, and evaluate prognostic value. METHODS: We searched PubMed, Web of Science, Scopus, and Embase up to December 2025 for observational studies. Two reviewers independently screened, extracted data, and assessed bias (NOS/JBI). Pooled standardized mean differences (SMDs) were calculated using random-effects models, with subgroup and sensitivity analyses. RESULTS: Seventeen studies were included. IMFI was significantly higher in KOA patients than controls (SMD&#xa0;=&#xa0;0.63, 95% CI 0.41-0.85, I2&#xa0;=&#xa0;84.7%). Anatomically, the anterior thigh muscles (rectus femoris, vastus lateralis, vastus medialis) demonstrated a significant pooled effect (SMD&#xa0;=&#xa0;0.96, 95% CI 0.66-1.25, I2&#xa0;=&#xa0;3.2%) and showed the strongest pooled association, whereas posterior, medial, and composite measures did not demonstrate significant associations. At the individual muscle level, a single study reported a notable association for the semimembranosus (SMD&#xa0;=&#xa0;1.25, 95% CI 0.57-1.93); however, this finding is based on limited evidence and requires confirmation in future studies. Subgroup by imaging modality: CT demonstrated a significant association (SMD&#xa0;=&#xa0;0.59, 95% CI 0.28-0.90), while MRI and ultrasound did not show significant associations. Elevated IMFI was also associated with reduced muscle strength, higher KOA incidence, structural progression, and increased knee replacement risk. CONCLUSION: A moderate positive association exists between IMFI and KOA, with notable muscle-specific heterogeneity. Anterior thigh muscles show the strongest pooled association, whereas individual muscle findings require further confirmation. These findings suggest that IMFI may represent a promising potential marker warranting further prospective investigation for risk stratification, though causality and its role in modifying disease progression remain to be established.

Humans

The effect of hip abductor or external rotator strength on dynamic knee valgus in healthy subjects-a systematic review with partial meta-analysis.

BACKGROUND: Weak hip abductors and external rotators (ER) have long been suggested to cause increased dynamic knee valgus. Patients are often prescribed strengthening of these muscles with the expectation that it will reduce their risk of pain and injury. The validity of this claim remains unclear. METHOD: We conducted a systematic review and partial meta-analysis assessing the association between hip strength and knee valgus in healthy subjects. An online search was conducted in May 2026. Databases included Medline, EMBASE, CINAHL and Google Scholar. INCLUSION CRITERIA: English language, asymptomatic subjects, dynamometric hip strength, single or multi-camera kinematic analysis, and statistical tests of difference or correlations between hip abductor or ER strength and dynamic valgus. Data were extracted concerning study design, subject characteristics, relevant outcome measures and statistics. RESULTS: 22 papers qualified for inclusion. Hip abductor correlations: 12 papers found no significant correlation, 2 supported the hypothesis and 2 found evidence contrary. Hip ER correlations: 8 papers found no significant correlation, 2 supported the hypothesis and 2 were contrary. Group differences for hip abduction strength: 3 papers found no difference, 2 found significant differences in support of the hypothesis, 1 found significant difference to contrary. Group differences for ER strength: 1 paper found no significant difference. None of the partial meta-analyses achieved statistical significance. CONCLUSION: Weakness in hip abductors or external rotators may not result in increased dynamic knee valgus in healthy subjects. While continued research may further illuminate our understanding, we discuss alternative explanations.

Humans

Effects of faba bean-based crisping culture on phenotypic characteristics, muscle quality, and serum metabolome in Nile tilapia: Screening biomarkers to assess the degree of crisping.

Feeding Nile tilapia (Oreochromis niloticus) a faba bean-based crisping diet enhances muscle hardness (crispness) and overall flesh quality. However, the underlying mechanisms and reliable biomarkers remain insufficiently defined. This study integrated phenotypic traits, muscle texture, collagen content, serum antioxidant enzyme activities (SOD, CAT, and GSH-Px), MDA levels, and serum metabolomics to understand the determinants of muscle crisping. Fish were assigned to a crisping diet or a control group for 90&#xa0;days. Individuals in the crisping group were implanted with passive integrated transponder (PIT) tags to enable correlation analyses among phenotypic traits (body weight/length/frame changes), serum indicators (NAM, FAD, and GSH-Px) and muscle hardness. Compared with controls, the crisping diet significantly increased muscle hardness, gumminess, and chewiness, accompanied by elevated collagen content. Antioxidant profiles were altered, with higher activities of serum SOD and CAT, together with elevated MDA levels and reduced GSH-Px activity (P&#xa0;<&#xa0;0.05). Metabolomic analysis identified 830 differential metabolites (682 upregulated and 148 downregulated), predominantly comprising carboxylic acids and derivatives, glycerophospholipids, and benzene derivatives. Enrichment analysis indicated significant involvement in general metabolic pathways, ATP-binding cassette (ABC) transporters, amino acid biosynthesis, and glycine, serine, and threonine metabolism (P&#xa0;<&#xa0;0.05). Notably, acetylpyruvate was upregulated in glutathione metabolism, nicotinate and nicotinamide metabolism, and galactose metabolism; pantothenic acid was upregulated in glycine, serine, and threonine metabolism; whereas &#x3b4;-tocotrienol was downregulated. Correlation analysis revealed weak negative associations between muscle hardness and phenotypic traits (body weight/length/frame changes D5-7, D5-10, D7-8) (P&#xa0;<&#xa0;0.05). In contrast, serum NAM and FAD were weakly positively correlated with muscle hardness, whereas GSH-Px showed a weak negative correlation (P&#xa0;<&#xa0;0.05). Collectively, these findings suggest that body weight, body length, frame measurements (D5-7, D5-10, and D7-8), and serum NAM, FAD, and GSH-Px are associated with the degree of muscle crispness in Nile tilapia fed a faba bean-based crisping diet and may serve as candidate biomarkers under these culture conditions.

Animals

Effects of blood flow restriction training combined with plyometric training on lower limb muscle strength and motor unit recruitment in basketball players: An experimental study.

OBJECTIVE: Previous studies have shown that plyometric training (PT) improves neuromuscular function and explosive power but not maximal strength. Blood flow restriction training (BFR) combined with low-intensity resistance training (RT) increases muscle mass and strength. This study investigated the effects of PT, and BFR combined with PT on lower-limb muscle function. METHODS: Twenty elite basketball players were randomly assigned to two groups: PT-alone group (PT, n&#x202f;=&#x202f;10) and BFR combine with PT group (PT-BFR, n&#x202f;=&#x202f;10). All participants underwent bodyweight-based plyometric training three times per week for eight weeks. Peak torque values for hip and knee flexion and extension, as well as root mean square (RMS) values derived from electromyography, were measured before and after the intervention. RESULTS: After the 8-week intervention, both groups showed significant improvements in knee flexion and extension peak torque at 180&#xb0;/s (all p&#x202f;<&#x202f;0.01). Between-group comparisons revealed greater gains in the PT-BFR group for hip extension and flexion at 60&#xb0;/s (p&#x202f;=&#x202f;0.036-0.002; &#x3b7;p2 = 0.225-0.233). RMS of the rectus femoris increased significantly more in the PT-BFR group than in the PT group (right: p&#x2009;=&#x2009;0.004, &#x3b7;p2 = 0.385; left: p&#x2009;=&#x2009;0.020, &#x3b7;p2 = 0.266), whereas no significant changes were observed in the gastrocnemius, tibialis anterior, or biceps femoris (all p&#x2009;>&#x2009;0.05). CMJ height also improved more in the PT-BFR group, with a significant group &#xd7;&#x2009;time interaction (p&#x2009;=&#x2009;0.042, &#x3b7;p2 = 0.210). CONCLUSION: Both training protocols enhanced bilateral lower-limb strength, with notable gains in the non-dominant leg; however, the magnitude did not differ substantially between groups. In contrast, compared with PT alone, BFR combined with PT produced superior enhancements in lower-limb muscle strength and neuromuscular recruitment. These findings suggest that when PT is employed to improve explosive power, it may be effectively combined with BFR to further augment muscular strength.

Humans

Effects of free-weight resistance training based on hexagonal barbell deadlift in older women: A 24-week randomized controlled trial.

PURPOSE: This randomized controlled trial examined effects of a 24-week hexagonal barbell deadlift (HBDL)-based free-weight resistance training program on body composition, trunk muscle function, and functional performance in older women. METHODS: Thirty-two women (67.6&#xa0;&#xb1;&#xa0;6.3&#xa0;years) were randomly assigned to an HBDL group (DG, n&#xa0;=&#xa0;16) or control group (CG, n&#xa0;=&#xa0;16). DG trained twice weekly for 24&#xa0;weeks under supervision. Primary outcomes were body composition and isokinetic trunk peak torque and average power at 60&#xb0;/s and 120&#xb0;/s. Secondary outcomes were isokinetic knee function, mobility, and maximal isotonic strength. Between-group differences after the intervention were examined by analysis of covariance (&#x3b1;&#xa0;=&#xa0;0.05). RESULTS: After intervention, DG showed greater trunk lean mass (+0.4&#xa0;kg vs. -0.2&#xa0;kg, p&#xa0;=&#xa0;0.006) than CG, and reductions in body fat percentage (-1.4% vs. +0.3%, p&#xa0;=&#xa0;0.003), total fat mass (-1.1&#xa0;kg vs. +0.3&#xa0;kg, p&#xa0;=&#xa0;0.013), and regional fat mass (trunk, gluteal, thigh; all p&#xa0;<&#xa0;0.05). Trunk extensor peak torque at 60&#xb0;/s (+26.0% vs. -6.3%, p&#xa0;<&#xa0;0.001) and average power at 60&#xb0;/s (+38.1% vs. -7.6%, p&#xa0;<&#xa0;0.001) and 120&#xb0;/s (+33.2% vs. +0.1%, p&#xa0;=&#xa0;0.002) improved significantly. DG also showed better eyes-closed static balance and 6-min walk performance (both p&#xa0;<&#xa0;0.05). Whole-body lean mass and lower-limb isokinetic strength did not differ between groups. Attendance was 89.6% with no adverse events. CONCLUSION: HBDL-based free-weight resistance training is a safe, feasible, and effective strategy to improve body composition, trunk extensor function, and mobility in older women.

Humans

Optimizing focal vibration therapy for balance and gait: A systematic review.

OBJECTIVE: This systematic review evaluated the efficacy of focal (localized) vibration therapy (FVT) applied to muscles/tendons on balance, gait, and mobility, with a specific focus on defining optimal vibration protocols (frequency, amplitude, dosing) and muscle-targeting strategies to maximize sensorimotor recovery. METHODS: A systematic review was conducted across six databases (CINHAL, Embase, Medline, Web of Science, Scopus, CENTRAL) from January 2000 to May 2025. Studies were included if they involved human participants, applied FVT therapeutically, and reported balance, gait, or mobility outcomes. Data extraction included study characteristics, intervention protocols, and outcomes. Methodological quality was assessed using the PEDro scale. RESULTS: Sixty-two studies (n&#x202f;=&#x202f;2090 participants) were included. Methodological quality assessment (PEDro scale) indicated 44% of studies met high-quality standards. Biomechanical analysis identified the quadriceps, gastrocnemius/soleus, and plantar muscles as the most effective vibration sites, given their critical roles in gait propulsion and postural stability. The synthesis of protocol data indicated a promising therapeutic window characterized by a vibration frequency of 80-120&#x202f;Hz (primarily fixed sinusoidal waveforms at a single frequency) and an amplitude of 0.2-0.5&#x202f;mm (reported only in 12 studies; amplitude was not reported in 23 studies), applied bilaterally for a minimum of 3 sessions per week over 4-12 weeks, which could lead to improved balance and gait performance with benefits sustained for up to 5 months. CONCLUSION: FVT shows potential to improve gait and balance, particularly when targeting lower-extremity muscles with optimized vibration parameters. To advance the field, future research must prioritize the development of standardized protocols and investigate neurophysiological mechanisms to refine FVT as a precision bioengineering solution for mobility deficits.

Humans

Age-related differences in motor unit behaviours and maximal strength: A systematic review and meta-analysis.

Ageing is associated with a decline in strength; however, the neural mechanisms underpinning these changes remain poorly understood. Motor unit discharge rate (MUDR) and recruitment threshold (MURT) regulate the magnitude of motoneuron output through rate coding and orderly recruitment, while discharge rate variability (MUDRV) reflects the steadiness of motoneuron output. Yet, age-related differences in these properties remain inconsistent across the literature. Therefore, this systematic review and meta-analysis quantified age-related differences in motor unit behaviours and their contribution to maximal isometric strength. Electronic databases (Medline, Embase, Scopus, PsycINFO, Ovid Emcare, CENTRAL, and Web of Science) were searched up to May 2025, yielding 1493 records; of these, 48 studies met the inclusion criteria. Standardised mean differences (SMDs) were calculated using random-effects models to compare older and younger adults, and methodological quality was assessed using the AXIS tool. Older adults exhibited markedly lower maximal strength than younger adults (SMD = -1.01; 95% CI -1.22, -0.79). MUDR was lower in older adults across all contraction intensities, with greater reductions at high forces (> 60% maximal voluntary contraction (MVC): SMD =&#x202f;-0.65; 95% CI -0.96, -0.34) compared to low forces (< 30% MVC: SMD = -0.34; 95% CI -0.50, -0.18). Discharge rate variability was greater (SMD = 0.44; 95% CI 0.15, 0.72), whereas recruitment thresholds relative to MVC were lower (SMD = -0.42; 95% CI -0.80, -0.03) in older adults. Collectively, these findings suggest that age-related alterations in motor unit discharge behaviour may contribute, at least in part, to reduced maximal strength in older adults.

Aging

Resistance versus concurrent training with three assigned protein targets in middle-aged and older women: a randomized 2 &#xd7; 3 factorial trial.

BACKGROUND: Evidence is limited regarding whether assigned protein targets modify responses to resistance training (RT) alone or to the same RT program plus cycling (concurrent training [CT]) in middle-aged and older women. This randomized 2&#x2009;&#xd7;&#x2009;3 factorial trial examined bioelectrical impedance analysis (BIA)-derived skeletal muscle mass (SMM; primary outcome), other body composition outcomes, muscular and functional performance, and cycle-derived estimated VO&#x2082;max. METHODS: In this randomized 2&#x2009;&#xd7;&#x2009;3 factorial trial, 108 women aged 40-77 years were assigned to 12 weeks of supervised RT or CT (identical RT followed by cycling) and protein targets of 0.8, 1.6, or 2.2 g&#xb7;kg-1&#xb7;d-1. Baseline-adjusted ANCOVA tested training&#x2009;&#xd7;&#x2009;protein interactions and marginal training and protein effects. Complete-case analyses included 83 participants. RESULTS: For SMM, no training-condition&#x2009;&#xd7;&#x2009;protein-target interaction (p&#x2009;=&#x2009;0.856), marginal protein-target effect (p&#x2009;=&#x2009;0.726), or marginal training-condition effect (p&#x2009;=&#x2009;0.273) was detected. CT had a lower baseline-adjusted week-12 BFP than RT (adjusted difference, -2.04 percentage points; 95% CI, -2.94 to -1.14; p&#x2009;<&#x2009;0.001). RT had a higher baseline-adjusted week-12 leg-press estimated 1-RM than CT (CT - RT: -6.68 kg; 95% CI, -8.32 to -5.04; p&#x2009;<&#x2009;0.001), whereas CT had a higher baseline-adjusted week-12 cycle-derived estimated VO&#x2082;max (adjusted difference, 4.53 mL&#xb7;kg-1&#xb7;min-1; 95% CI, 3.80 to 5.25; p&#x2009;<&#x2009;0.001). No detectable marginal protein-target effects or training-condition&#x2009;&#xd7;&#x2009;protein-target interactions were observed for the key secondary outcomes. CONCLUSIONS: No detectable differences in SMM or key secondary outcomes were attributable to assigned protein target. Compared with RT, CT favored estimated aerobic fitness and BFP, whereas RT favored leg-press strength. Because CT included additional cycling and greater exercise exposure, these differences cannot be attributed solely to training modality. Null protein findings do not establish equivalence among doses.

Humans

Exploratory identification and cellular functional characterization of ppiabl as a candidate gene associated with growth traits in Paralichthys olivaceus.

The Japanese flounder (Paralichthys olivaceus) is an important mariculture species. However, the genetic mechanisms underlying its growth traits remain poorly understood. To explore the genetic basis of growth variation, whole-genome resequencing was performed in a cultured cohort of 60 individuals, followed by exploratory genome-wide association analysis and candidate-gene prioritization. The results revealed heritability estimates of 0.40 for body weight and 0.24 for body length, with substantial overlap in associated loci between the two traits. Exploratory association and variant-annotation analyses prioritized ppiabl, which carries a nonconservative missense variant, as a candidate gene for further investigation. Tissue expression analysis showed that ppiabl was highly expressed in muscle tissue. This gene encodes a protein belonging to the conserved peptidyl-prolyl cis-trans isomerase family. In Japanese flounder primary muscle cells, ppiabl knockdown was associated with altered expression of growth-related genes and an increased G1-phase fraction, whereas overexpression produced changes in the opposite direction. In line with this, fast-growing individuals were found to have significantly larger muscle fiber areas than slow-growing ones. These findings suggest that ppiabl may be involved in muscle-related cellular processes associated with growth variation in Japanese flounder, although its contribution to whole-animal growth requires further validation. Overall, this exploratory study prioritizes ppiabl as a candidate gene potentially associated with growth-related cellular processes in Japanese flounder, although validation in larger independent populations and in vivo models is required.

Animals

Association Between 24-Hour Blood Pressure and Rates of Retinal Nerve Fiber Layer Progression in Glaucoma: The Vascular Imaging in Glaucoma Study.

PURPOSE: Low systemic blood pressure (BP) has been implicated as a risk factor for glaucoma progression. The purpose of this study was to investigate the association between 24-hour BP and rates of retinal nerve fiber layer (RNFL) loss in eyes with primary open-angle glaucoma. DESIGN: Prospective cohort study. PARTICIPANTS: Seventy-nine eyes from 42 subjects with glaucoma (mean age, 68.5 &#xb1; 7.6 years) enrolled in the Vascular Imaging in Glaucoma Study at the Bascom Palmer Eye Institute. METHODS: Participants underwent 24-hour ambulatory BP monitoring at baseline. Follow-up evaluations were conducted at 4-month intervals and included ophthalmic examination, BP measurement, and peripapillary RNFL thickness measurement with spectral-domain optical coherence tomography. The association between BP and RNFL loss over time was assessed using linear mixed-effects models adjusted for age, sex, race, baseline RNFL thickness, central corneal thickness, and intraocular pressure. MAIN OUTCOME MEASURES: The effect of baseline 24-hour mean arterial pressure (MAP), systolic BP (SBP), and diastolic BP (DBP) on the rate of average RNFL loss over time. RESULTS: Eyes underwent an average of 13 &#xb1; 3 optical coherence tomography exams over 43 &#xb1; 10 months of follow-up. The mean rate of RNFL loss was -0.34 &#xb1; 0.64 &#xb5;m/y (median: -0.32; interquartile range: -0.66 to -0.04 &#xb5;m/y). After adjusting for confounding factors, every 10 mm Hg lower in 24-hour minimum MAP, SBP, and DBP was associated with -0.542 &#xb5;m/y (P < .001), -0.360 &#xb5;m/y (P = .003), and -0.458 &#xb5;m/y (P = .008) faster RNFL loss, respectively. Eyes in the lowest quartile of average 24-hour MAP (81-90 mm Hg) and minimum 24-hour DBP (35-47 mm Hg) experienced significantly faster progression compared to those in the highest quartile, with differences of -0.68 &#xb5;m/y (P = .017) and -0.63 &#xb5;m/y (P = .030), respectively. CONCLUSIONS: Lower systemic BP, especially minimum MAP, SBP, and DBP measured by 24-hour ambulatory BP monitoring, is associated with faster rates of RNFL loss in primary open-angle glaucoma eyes. 24-hour BP monitoring may help predict glaucoma patients at greater risk of progression.

Humans

Peripheral pain threshold, glycaemic status, and LAMP3 genetic variation: A community-based analysis.

Diabetic polyneuropathy is a common complication of diabetes, yet substantial inter-individual variation in peripheral pain perception suggests underlying genetic influences. This population-based study investigated clinical, metabolic, and genetic determinants of pain threshold using intraepidermal electrical stimulation in 906 participants from the Iwaki Health Promotion Project 2017. Genome-wide association analysis identified 12 loci showing suggestive associations, among which a missense variant in LAMP3 (rs482912) was prioritized as a biologically plausible candidate. Phenotype-stratified analyses showed that individuals carrying the CT or CC genotypes had lower PINT indices than those with the TT genotype, indicating reduced pain thresholds. Notably, the CC genotype retained an association with lower pain threshold using intraepidermal electrical stimulation under conditions of metabolic stress, including impaired glucose tolerance, elevated HbA1c, and obesity, whereas this association was attenuated in the presence of hypertension. Single-cell RNA sequencing analysis of human skin revealed that LAMP3-positive mature dendritic cells, enriched in immunoregulatory molecules, exhibited transcriptional enrichment of inflammatory, antigen-presenting, and nociception-related pathways, including NF-&#x3ba;B, JAK-STAT, cytokine signaling, and neuroimmune sensitization cascades. Autopsy-based skin analysis further demonstrated genotype-associated differences in dermal LAMP3-positive cell infiltration and CD8-positive T-cell abundance, while CD4-positive T-cell abundance and intraepidermal nerve fiber density remained unchanged across genotypes. Taken together, these findings suggest a potential association between LAMP3 variation and individual differences in peripheral pain threshold and provide biological context supporting a role for neuroimmune interactions in early sensory modulation under metabolic stress. Given the suggestive genetic evidence and indirect mechanistic data, these observations should be interpreted as exploratory and hypothesis-generating.

Humans

Morphological changes and transcriptomic insights into skeletal development of embryos and larvae of the sea urchin Strongylocentrotus intermedius.

To explore morphological features and molecular dynamics underlying skeletogenesis in the sea urchin Strongylocentrotus intermedius, we conducted combined morphological observation and comparative transcriptome analyses across representative embryonic and larval developmental stages. Morphological results showed that triradiate spicules first emerged at the gastrula stage. The 8-arm pluteus stage was identified as a key phase for skeletal remodeling, during which new three-radiate crystals transformed into complex stereoscopic ossicles including tube feet, spines and test plates. Transcriptomic data indicated that most differentially expressed genes (DEGs) were downregulated from the blastula to gastrula. The altered expression of basal metabolic genes and extracellular matrix genes including Colp2&#x3b1; and calm may be correlated with the linear mineralization of early spicules, which potentially reflects an energy adjustment pattern in developing larvae. During the transition from 6-arm to 8-arm pluteus, expression changes of calmodulin-like, Colp2&#x3b1; and SISin18G001660 suggest potential associations with regional calcium deposition and modifications of skeletal matrix properties. This work systematically characterizes morphological traits and transcriptional dynamics of skeletogenesis in S. intermedius. Its early spiculogenesis follows the conserved developmental pattern of echinoderms, while massive formation of stereoscopic ossicles occurs at the 8-arm pluteus stage. Stage-specific transcriptional changes across key larval skeletogenic stages are uncovered, offering transcriptomic resources for functional verification of skeletal regulatory genes.

Animals

Efficacy and Safety of Bimagrumab in Adults With Obesity and Metabolic Dysfunction: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

AIMS: This study aims to systematically evaluate the efficacy of bimagrumab on body composition and glucose parameters in adults with obesity and metabolic dysfunction and its safety profile. METHODS: We searched MEDLINE, PubMed, Embase, and the Cochrane Library on April 20, 2026, for randomized controlled trials (RCTs) assessing bimagrumab treatment in adults with obesity, insulin resistance, or type 2 diabetes mellitus (T2DM). The risk of bias was assessed using the Cochrane Risk of Bias tool (RoB 2), and meta-analyses of efficacy and safety data were conducted using R software. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system was used to assess the strength of evidence. The study was registered with PROSPERO (CRD420261377110). RESULTS: Of the 134 retrieved records, 4 RCTs (enrolling 268 participants) were included. The included population represented a broad spectrum of metabolic dysfunction, from obesity and nondiabetic insulin resistance to established T2DM. Compared with placebo, bimagrumab treatment significantly reduced total weight (mean difference [MD] -4.85&#x2009;kg, 95% confidence interval [CI] -6.82 to -2.88), fat mass (-4.72&#x2009;kg [-8.05 to -1.40]), and glycated haemoglobin (HbA1c) (-0.13% [-0.23 to -0.03]) and significantly increased total lean mass (1.66&#x2009;kg [0.81 to 2.51]). However, bimagrumab led to an increase in low-density lipoprotein (LDL) concentrations of 0.47&#x2009;mmol/L [0.03 to 0.91] and significantly increased incidences of discontinuation (risk ratio [RR] 5.75 [1.61 to 20.46]), muscle spasms (RR 10.44 [4.23 to 25.75]), and diarrhoea (RR 4.91 [2.38 to 10.11]). CONCLUSION: Bimagrumab effectively reversed adverse effects on body composition in obese individuals, resulting in significant fat reduction, increased skeletal muscle mass, and improved glycemic control, suggesting that bimagrumab is a promising new target for personalized metabolic therapy.

Humans

Safety of insulin eye drops in the treatment of open angle glaucoma: a randomized phase I clinical trial.

OBJECTIVE: The progression of glaucoma despite adequate intraocular pressure (IOP) control highlights the need for neuroprotective and neuroregenerative therapies. Preclinical studies suggest insulin promotes retinal ganglion cell survival and regeneration, but its safety in higher concentrations (100 and 500 units/mL), administered topically, has been poorly characterized in humans. We aim to assess the safety and tolerability of these two concentrations of insulin eye drops in patients with open-angle glaucoma (OAG). DESIGN: A phase I, randomized, double-blind, placebo-controlled, single-centre clinical trial. PARTICIPANTS: Patients with mild to moderate OAG were randomized 2:2:1 to receive once-daily topical insulin U-100, U-500, or placebo in 1 eye for 5 days, with follow-up visits at 1, 3, and 6 months. The primary safety outcomes include glycemia, serum potassium, ocular adverse events (AEs), and ocular tolerability scores. Secondary outcomes included IOP, best-corrected visual acuity (BCVA), retinal nerve fibre layer thickness, ganglion cell complex, visual field, and OCT angiography. RESULTS: Eighteen open-angle glaucoma patients were enrolled (mean age: 66.2 &#xb1; 10.1 years). No serious AEs related to insulin were observed. One asymptomatic, transient near-hypoglycemia event occurred in a fasting participant (3.9 mmol/L), with no recurrence after dietary adjustment. No significant changes were found in serum potassium, IOP, BCVA, visual fields, or OCT. Ocular symptoms in the insulin groups were limited to transient, mild burning sensation upon application. One participant experienced cystoid macular edema at 3 months, which was attributed to pre-existing ocular pathology. CONCLUSION: Topical insulin at 100 and 500 units/mL concentrations was well tolerated in patients for short-term use and did not result in significant systemic or ocular toxicity.

Aged

Functional constipation in pregnancy and its association with dietary intake and physical activity: a cross-sectional study.

BACKGROUND: Functional constipation (FC) is a common complaint during pregnancy and has been reported to be associated with physical activity and dietary intake. However, previous studies have reported inconsistent findings. Therefore, this study aimed to determine the prevalence of FC and examine its association with physical activity and dietary intake among pregnant women. METHOD: In this cross-sectional study, 381 healthy pregnant women attending urban health centres in Tabriz, Iran, between January 2024 and February 2025, were selected using a multistage cluster sampling method. FC was diagnosed according to the Rome IV criteria. Data were collected through face-to-face interviews using the International Physical Activity Questionnaire (IPAQ) and the Food Frequency Questionnaire (FFQ). Multivariable Generalised Estimating Equations (GEE) analysis was performed to identify factors associated with FC. RESULTS: The overall prevalence of FC throughout pregnancy was 37%. In the first trimester, 41 out of 73 women (56%) had FC, while in the second trimester 53 out of 146 women (36%), and in the third trimester 47 out of 162 women (29%) were affected. Multivariate GEE indicated that both higher dietary fibre intake (aOR= 0.88, 95%CI 0.86-0.91, p&#x2009;<&#x2009;0.001) and higher fluid intake (aOR= 0.59, 95%CI 0.52-0.67, p&#x2009;<&#x2009;0.001) were associated with a reduced risk of FC. A normal BMI was associated with a lower risk of FC (aOR= 0.35, 95% CI 0.16-0.77, p&#x2009;=&#x2009;0.009), whereas, secondary education was associated with a higher risk (aOR= 2.81, 95%CI 1.33-5.95, p&#x2009;=&#x2009;0.007). Physical activity (aOR= 1.00; 95%CI 1.00 to 1.01; p&#x2009;=&#x2009;0.168), and other demographic characteristics (p&#x2009;>&#x2009;0.05) were not independently associated with FC after adjustment. CONCLUSION: FC is highly prevalent during pregnancy and may adversely affect women's quality of life. Higher dietary fibre and fluid intake were associated with lower odds of FC, highlighting the importance of healthy lifestyle behaviours during pregnancy. Prospective longitudinal studies are warranted to confirm these findings.

Humans

Premeal insulin administration lowers postprandial blood glucose and increases myocardial microvascular blood flow in people with type 1 diabetes: a randomised, crossover clinical trial.

AIMS/HYPOTHESIS: We aimed to evaluate whether prandial insulin timing affects vascular function in people with type 1 diabetes. Our hypothesis was that premeal insulin administration would lead to greater myocardial microvascular blood flow (MBF) via blunting postprandial hyperglycaemia. METHODS: People with type 1 diabetes between 18 and 35 years of age with BMI <30 kg/m2 underwent two protocols with a 1:1 randomised crossover design wherein prandial insulin was injected either 15 min before or 15 min after meal intake began. To provide a physiological comparison, age-, sex- and BMI-matched control participants completed one study where they consumed the same meal but received no exogenous insulin. Glucose, insulin, vascular function (including ultrasound measures of myocardial and skeletal muscle microvascular perfusion, aortic stiffness, brachial artery endothelial function) and biomarkers of systemic inflammation and endothelial dysfunction were assessed at baseline and then 2 h after meal ingestion within each protocol. The primary outcome was change in myocardial MBF within each protocol. Study personnel assessing outcomes were masked to group assignment. RESULTS: Eighteen people with type 1 diabetes and 18 matched control participants were analysed within each protocol. Glucose area under the curve was significantly greater (p=0.015) in the postmeal insulin study compared with the premeal insulin study in participants with type 1 diabetes. Myocardial microvascular flow velocity significantly increased (p=0.031) with premeal insulin administration in people with type 1 diabetes and this consequently led to greater myocardial MBF (p=0.044). There were no changes in myocardial MBF within the other protocols. Changes in vital signs were similar between all protocols. CONCLUSIONS/INTERPRETATION: Appropriately timed premeal insulin led to lower postprandial blood glucose along with increased myocardial MBF in people with type 1 diabetes. Further work is needed to determine the underlying aetiology of these changes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04730882.

Humans