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Genome-wide characterisation of the myosin light chain gene family in Chinese perch (Siniperca chuatsi) and its expression patterns in muscle fibre types and injury response.

The Class II myosin light chain (myl) genes in Chinese perch (Siniperca chuatsi) have not yet been systematically characterised, and relationships with muscle fibre specification, development, and injury-associated remodelling remain unclear. In this study, fast and slow muscle fibres were initially distinguished using myofibrillar ATPase histochemistry. Subsequently, genome-wide mining identified 16 Class II myl genes, comprising eight essential and eight regulatory light-chain subunits. Their conserved-domain features, chromosomal distribution, phylogenetic relationships and expression profiles were analysed. Transcriptomic profiling showed that summed myl transcript abundance was higher in fast muscle than in slow muscle, accounting for 67.2% of the pooled myl transcript pool across the two muscle types (paired t-test, raw P = 0.036). mylpfa, myl1 and mylz3 were the major fast-muscle-associated genes, whereas myl10, myl2b and myl13 were preferentially expressed in slow muscle at the transcript level. These patterns support these genes as candidate fibre-type-associated expression markers. Developmental profiling identified stage-associated myl expression patterns, including a possible expression shift between mylpfb and mylpfa. In the descriptive injury-repair time course (d0-d7), FPKM profiles indicated that fast-muscle-associated genes (mylpfa, mylz3 and myl1) were lower at d1 and recovered by d3, whereas several slow-muscle-associated genes showed biphasic transcript-level increases. The slow-muscle-associated RLC gene mylpfb showed a delayed expression peak at d7. Notably, the embryonic isoform myl6l showed a modest increase from approximately 2 FPKM at d0 to 4-5 FPKM after injury, suggesting a possible injury-associated expression pattern that requires further validation. Together, these findings provide a genome-wide description of the Chinese perch myl gene family and identify candidate fibre-type-associated genes and descriptive injury-associated isoform expression patterns.

Animals

The effects of nitrate and nitrite supplementation on mitochondrial respiration in permeabilized muscle fibres in young healthy adults.

Nitric oxide (NO) is a direct regulator of mitochondrial respiration. Nitrate (NO3-) and nitrite (NO2-) are good sources of NO, but whether their effects on mitochondrial respiration differ between in vivo and in vitro administration remains unclear. In Study 1, 8 participants consumed NO3- -rich beetroot juice (BR) (∼12.8 mmol NO3-) and NO3- -depleted placebo beetroot juice (PL) (∼0.08 mmol NO3-) acutely and chronically for 2 weeks in a randomised, double-blind, crossover design. A substrate-uncoupler-inhibitor titration (SUIT) protocol was used to assess mitochondrial respiration using high-resolution respirometry (oxygen tension: ∼200-450 μM) in permeabilized muscle fibres. In Study 2, skeletal muscle samples were collected from 11 participants. In a randomised, crossover design, different doses (0, 1.5, and 3.0 μM) of sodium nitrite (NaNO2) were administered to permeabilized muscle fibres. Mitochondrial respiration was measured using the same SUIT protocol under lower oxygen tension (∼50-200 μM). Although muscle NO3- concentration significantly increased after both acute and chronic BR supplementation, mitochondrial respiration and exercise performance did not differ between PL and BR in either condition. Similarly, absolute oxygen flux across different respiratory states were not different between different doses of NaNO2. However, the leak control ratio, reflecting the degree of uncoupling of mitochondrial respiration, was significantly higher with 3.0 μM NaNO2 administration (0.12 ± 0.05) compared to 0 μM NaNO2 administration (0.09 ± 0.04, P = 0.03). These findings, involving both in vivo and in vitro administration approaches, albeit in the presence of relatively high oxygen concentrations, suggest that neither NO3- nor NO2- improves mitochondrial respiration, at least in young healthy adults.

Humans

A systematic review and meta-analysis of OCT-based ophthalmic changes in amyotrophic lateral sclerosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease marked by motor decline and respiratory failure. Optical coherence tomography (OCT), a non-invasive imaging technique, has been explored for detecting retinal structural changes that may reflect neurodegeneration in ALS. While some studies report thinning of retinal layers, findings remain inconsistent. Therefore, a meta-analysis is needed to clarify the extent of retinal involvement and the potential of OCT as a biomarker in ALS. METHODS: A systematic literature search was conducted across PubMed, EMBASE, and Cochrane databases for studies published between 2010 and May 2025. Study quality was assessed using the Newcastle-Ottawa Scale (NOS), and publication bias was evaluated through funnel plot asymmetry and Egger's test. Pooled effect sizes were calculated using random-effects models to account for between-study heterogeneity, and differences in OCT parameters between ALS patients and healthy controls were expressed as standardized mean differences (SMD) with 95% confidence intervals (CI). Statistical heterogeneity was quantified using the I2 statistic. RESULTS: A total of 17 studies were included in the present meta-analysis. The primary unadjusted global model demonstrated significant reduction of retinal nerve fibre layer (RNFL) thickness in ALS patients compared to controls (unadjusted SMD = -0.295, 95% CI: -0.522, -0.068). Upon applying a Design Effect variance inflation model to address fellow-eye non-independence, the pooled estimate remained robustly significant across a conservative range of intraclass correlations (SMD ranged from -0.256 to -0.249). Subgroup analyses revealed that RNFL thinning was particularly pronounced in spinal-onset ALS (SMD = -0.54, 95% CI: (-0.98, -0.10). When studies were stratified by the region of conduct, RNFL and macular thinning reached statistical significance only within the non-Asian subgroup, though the formal test for subgroup differences was not significant. CONCLUSION: This meta-analysis demonstrates significant bilateral RNFL thinning in ALS, with relative preservation of the Inner Nuclear Layer and Ganglion Cell Layer - Inner Plexiform Layer, supporting retinal neurodegeneration as a feature of this multisystem disorder. SYSTEMATIC REVIEW REGISTRATION: PROSPERO identifier CRD420251076035.

Humans

Role of bioprocessing in modifying cardiometabolic outcomes of an oat-based dairy alternative in a randomised controlled clinical intervention.

BACKGROUND & AIMS: A healthy diet rich in fibre-containing foods such as oats supports cardiometabolic health. Bioprocessing methods, including fermentation and enzymatic treatment, may further enhance the health benefits of oat-based foods by altering their physicochemical properties. The aims of this study were to investigate the effects of consuming fermented and non-fermented oat-based products enriched with fibre and protein on cardiometabolic outcomes gastrointestinal symptoms, and to consider how assessed physicochemical and nutritional differences between the products might relate to any observed effects. METHODS: In a 12-week randomised crossover trial, 56 adults with mild metabolic deterioration consumed fermented (gurt) and non-fermented (porridge) oat-based products enriched with fibre and protein as part of their habitual diet for three weeks each. The study products were specifically developed and prepared for this study using identical ingredients. Primary cardiometabolic factors and gastrointestinal symptoms (GSRS) were measured at four time points, while secondary outcomes were assessed at baseline and after both product periods. Physicochemical and nutritional characterization of the study products included cereal &#x3b2;-glucan (BG) and protein molecular weight distribution, starch and sugar analysis, microscopy, acidity, and viscosity. RESULTS: During the gurt consumption, non-high-density lipoprotein (non-HDL) and low-density lipoprotein (LDL) cholesterol concentrations decreased (-0.15 &#xb1; 0.51 mmol/L, p = 0.028; and -0.12 &#xb1; 0.46 mmol/L, p = 0.047, respectively), with a minimal impact on blood pressure and GSRS scores. Additionally, ferritin was lower after the gurt compared with baseline (-4.00 [-16.50, 6.25] &#x3bc;g/L, p = 0.015). Similarly, ferritin levels were lower after the porridge period (-7.50 [-20.50, 4.25] &#x3bc;g/L), accompanied with a modest decrease in blood pressure and HbA1c. These effects, however, did not substantially differ between the product periods. Insulin showed a significant sequence effect (psequence&#x2217;time <0.05) and was analysed in sequence groups. Insulin levels significantly decreased during the gurt consumption in the group that started with the porridge (-2.22 &#xb1; 6.16 mU/L, p = 0.015). Fermentation and enzymatic treatment induced significant changes in BG MW, starch, and composition in the gurt, which may alongside with increased fibre intake during the intervention explain the observed results. CONCLUSION: Consuming a fermented, oat-based gurt as part of habitual diet may improve cholesterol metabolism, likely due to increased oat fibre intake rather than fermentation as such. Moreover, greater intake of oat-based products, regardless of processing, can reduce ferritin concentrations and marginally improve other cardiometabolic factors. The study was registered in ClinicalTrials.gov as NCT06393114.

Humans

Increasing gut short-chain fatty acids protects intestinal barrier function but does not spare muscle glycogen or impact aerobic performance.

Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is needed. This study aimed to determine whether increasing colonic SCFA availability impacts intestinal barrier function, substrate metabolism, muscle glycogen and aerobic performance in healthy adults. Using a randomized, double-blind, crossover design 12 active men (age 18-30&#xa0;years;40.0&#xa0;&#xb1;&#xa0;7.1&#xa0;mL/kg/min) performed prescribed exercise and consumed a provided diet supplemented with acetylated and butyrylated high-amylose maize starch engineered to deliver SCFA to the colon (HAMS-A/B) or low-amylose maize starch (LAMS) for 7 days, separated by a 2 week washout. Indirect calorimetry, stable isotopes and blood, muscle and urine biomarkers were measured on intervention day 8 while participants completed 90&#xa0;min of steady-state cycle ergometry (ExSS; 60 &#xb1; 5%) followed by a 5&#xa0;km treadmill time trial. HAMS-A/B, relative to LAMS, increased faecal and serum SCFA. Multiple markers of intestinal barrier damage and permeability were lower, and the respiratory exchange ratio during ExSS was higher (0.02 [95% confidence interval (CI): 0.01, 0.03], Ptreatment&#xa0;<&#xa0;0.001) following HAMS-A/B versus LAMS. However no between-treatment difference in glucose turnover, muscle glycogen depletion (14&#xa0;&#xb5;mol/kg/g dry wt. [95% CI: -116, 143], Pinteractio n&#xa0;=&#xa0;0.613) or TT performance (5&#xa0;s [95%CI: -44, 54], Ptreatment&#xa0;=&#xa0;0.816) was observed. Increasing colonic and circulating SCFA modestly altered substrate oxidation and preserved intestinal barrier function during endurance exercise. However effects were not sufficient to spare muscle glycogen or increase aerobic endurance performance, leaving the practical relevance unclear and underscoring challenges inherent in translating promising preclinical findings to humans. KEY POINTS: Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is lacking. A gut microbiota-targeted dietary supplementation strategy was used to deliver SCFA to the colon and successfully increased colonic and systemic SCFA concentrations in healthy, physically active adults before and during an endurance exercise bout and aerobic performance test. Increasing colonic and systemic SCFA availability preserved intestinal barrier function but did not impact glucose turnover, alter protein expression in muscle or spare muscle glycogen during endurance exercise. Increasing colonic and systemic SCFA availability did not impact aerobic endurance performance.

Humans

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

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

King's Mill anterior-posterior and transverse versus paracervical block in operative outpatient hysteroscopy: a randomised trial.

BACKGROUND: Pain control during operative outpatient hysteroscopy remains a clinical challenge, with the paracervical block (PCB) showing inconsistent efficacy. The King's Mill Anterior-Posterior and Transverse (KAPT) block targets the Lee-Frankenhauser plexus within the uterosacral ligament complex, where the highest density of uterine and cervical sensory fibres lies. We compared the KAPT block with the PCB in operative outpatient hysteroscopy. METHODS: Single-centre, participant- and outcome assessor-blinded randomised controlled trial in a UK district general hospital. Forty-eight women undergoing operative outpatient hysteroscopy were randomised 1:1 to the KAPT block or the PCB, each delivered with 10&#x2009;ml of prilocaine. Pain was measured on a 10-point Visual Analogue Scale (VAS) during the procedure and 10&#x2009;minutes post-procedure (co-primary endpoints), and during cervical dilatation (exploratory). Analyses used the Mann-Whitney U test on an intention-to-treat basis, with Hodges-Lehmann median differences, percentile bootstrap 95% confidence intervals, and a hierarchical fixed-sequence testing strategy. RESULTS: Median intra-procedural VAS was 1 (IQR 0 to 3) with the KAPT block versus 2 (IQR 1 to 6) with the PCB (Hodges-Lehmann median difference -1.00, 95% CI -3.00 to 0.00; p&#x2009;=&#x2009;0.040). At 10&#x2009;minutes post-procedure, median VAS was 0 (IQR 0 to 1.25) versus 2 (IQR 0 to 3.25) (median difference -1.00, 95% CI -2.00 to 0.00; p&#x2009;=&#x2009;0.011). Both co-primary endpoints reached significance under hierarchical testing. Cervical dilatation pain did not differ significantly (p&#x2009;=&#x2009;0.146). Satisfaction was 100% in both arms; willingness to recommend was 100% (KAPT) versus 95.8% (PCB). No serious adverse events occurred. CONCLUSIONS: The KAPT block was associated with lower intra-procedural and post-procedural pain than the PCB, with effect sizes consistent with a clinically meaningful difference. These findings support the KAPT block as a superior, anatomically targeted alternative to the PCB and justify evaluation in a larger multicentre trial.Trial registration: ISRCTN15619382.

Humans