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Aim: The aim was to examine the prevalence of metabolic dysfunction–associated steatotic liver disease (MASLD), a risk factor for atherosclerotic cardiovascular disease, and its association with glycaemic control metrics in children and adolescents with type 1 diabetes (T1D). Materials and Methods: We enrolled 244 children and adolescents with T1D (115 girls, mean age: 16.2 ± 3.2 years). The diagnosis of MASLD was defined by the presence of hepatic steatosis on ultrasonography in combination with at least one of five common cardiometabolic risk factors. Metrics of short‐term and long‐term glycaemic control, blood pressure, lipids, anthropometric characteristics and three genetic variants strongly related to MASLD susceptibility (rs738409 [patatin‐like phospholipase domain‐containing 3], rs58542926 [transmembrane 6 superfamily member 2] and rs1260326 [glucokinase regulator]) were assessed. Characteristics of these subjects with and without MASLD were compared using the unpaired Student t test, Mann–Whitney test or χ2 test as appropriate. Logistic regression analyses were performed to determine the main independent predictors of MASLD. Results: The prevalence of MASLD was 27.5% in children and adolescents with T1D. Blood pressure, total cholesterol, low‐density lipoprotein (LDL) cholesterol, non‐high‐density lipoprotein cholesterol, HbA1c and time above range (TAR) were significantly higher in subjects with MASLD than in those without MASLD. Mean HbA1c values from diabetes onset (adjusted odds ratio [OR]: 1.703, 95% confidence interval [CI]: 1.040–2.787, p = 0.034), TAR (adjusted OR: 1.028, 95% CI: 1.009–1.047, p = 0.006) and plasma LDL cholesterol (adjusted OR: 1.045, 95% CI: 1.013–1.078, p = 0.004) were independently associated with the presence of MASLD. Conclusions: MASLD is a common condition in children and adolescents with T1D. The mean HbA1c values from diabetes onset, TAR and LDL cholesterol levels were the independent predictors of MASLD. [ABSTRACT FROM AUTHOR]

Summary: Background: The diagnosis of monogenic obesity is burdened by frequent variants of uncertain significance (VUS). We describe our real‐life approach of variant reassessment over time and we assess whether inconclusive variants are decreasing in monogenic obesity. Methods: We tested for monogenic obesity (genes: LEPR, POMC, ADCY3, PCSK1, CARTPT, SIM1, MRAP2, LEP, NTRK2, BDNF, KSR2, MAGEL2, SH2B1, MC4R, MC3R) in 101 children/adolescents (11.7 [7.3–13.7] years, 3.6 [3.3–4.0] z‐BMI) in Verona and 183 (11.3 [8.4–12.2] years, 3.2 [2.7–3.9] z‐BMI) in Naples from January 2020 to February 2023. In March–July 2024 we reassessed the baseline variants by updated software interpretation and literature renavigation. Results: We initially found 20 VUS, 4 Likely Pathogenic (LP), 5 Likely Benign (LB) and 1 benign variant in 33 individuals. At follow‐up, 6 VUS were reclassified as benign/LB, one LP as pathogenic and 3 LB as benign. Overall, 10/30 variants (6/18 in Verona, 3/11 in Naples and a variant found in both centres) were reclassified, leading to a less uncertain report for 13 of 33 variant‐carrying patients. Monogenic obesity was diagnosed in 3 probands in Verona and 4 in Naples, carrying variants at MC4R or NTRK2. Conclusion: Our variant reassessment was effective to improve classification certainty for the 39% of patients and suggested that the molecular diagnosis of monogenic obesity is becoming more accurate over time. [ABSTRACT FROM AUTHOR]

Aims: Fibroblast growth factor 21 (FGF21) decreases hepatic lipogenesis in animal models, and FGF21 analogues decrease serum triglycerides (TG) in adults in phase‐2 trials. On the other hand, serum FGF21 is associated with higher TG in observational studies of people with obesity, raising a sort of paradox. We tested the hypothesis that FGF21 is induced by TG in youth with obesity, as a compensatory mechanism. Materials and Methods: We recruited 159 children/adolescents with obesity (80 males, 12.7 ± 2.1 years). Besides serum FGF21 and lipid dosages, we genotyped the Pro446Leu variant at glucokinase regulator (GCKR) as a known marker of genetically increased hepatic de novo lipogenesis, and we used it as an instrumental variable to establish a cause‐and‐effect relationship between FGF21 and TG, according to a Mendelian randomization analysis. Results: The Pro446Leu variant increased circulating TG (β = +0.35, p < 0.001), which was positively associated with circulating FGF21 (β = +0.42, p < 0.001). The Pro446Leu variant increased FGF‐21 (β = +0.14, p = 0.031) with the expected slope (β‐coefficient) in case of association entirely mediated by TG: 0.35 (slope between Pro446Ala and TG) × 0.42 (slope between TG and FGF21) = 0.14. Conclusions: Hepatic lipogenesis, marked by GCKR‐modulated triglycerides, is significantly associated with increased serum FGF‐21 in children/adolescents with obesity. [ABSTRACT FROM AUTHOR]

Introduction: Type 1 diabetes (T1D) is associated with an increased risk of cardiovascular disease. Insulin resistance is an important cardiovascular risk factor (CVRF), also in subjects with T1D, but the influence of the genetic predisposition of insulin resistance on cardiovascular risk is still unknown in T1D. We aimed to determine whether a genetic score composed of six variants, previously associated with insulin resistance and type 2 diabetes (T2D) risk, associates with insulin sensitivity and known CVRFs in children and adolescents with T1D. Materials and Methods: 330 children and adolescents (174 males; mean age 15.7 ± 3.5 years) with T1D were genotyped for the following genetic variants: rs1801278 (IRS1), rs1044498 (ENPP1), rs2295490 (TRIB3), rs1801282 (PPARG), rs780094 (GCKR), and rs35767 (IGF1). An additive genetic risk score (GRS) and cardiovascular risk score (CVRS) were calculated. Anthropometric, glycemic control, insulin sensitivity, blood pressure, and biochemical parameters were assessed. Multivariate regression between evaluated phenotypes and GRS was performed. Results: We found a significant association between the GRS and estimated insulin sensitivity (β = −0.027 [−0.040 to −0.013], R2 = 0.86, p≤ 0.001), diastolic blood pressure (β = 0.68 [0.08–1.27], R2 = 0.20, p = 0.026), triglycerides (β = 4.26 [1.74–6.77], R2 = 0.13, p = 0.001), waist to height ratio (β = 0.003 [0.001–0.006], R2 = 0.75, p = 0.010), non-HDL-cholesterol (β = 3.63 [1.39–5.87], R2 = 0.12, p = 0.002), and CVRS (β = 0.063 [0.008–0.118], R2 = 0.19, p = 0.025), independent of age, sex, BMI, pubertal stage, diabetes duration, glycated hemoglobin, type of treatment, and total insulin requirement. The addition of the GRS to established clinical risk factors significantly improved the discriminatory capability of the regression model for predicting subjects with more CVRFs (C-statistic 0.89 [95% CI: 0.84–0.95] versus 0.83 (0.73–0.93); p = 0.037). Conclusions: Insulin resistance and T2D risk-associated genetic variants influence insulin sensitivity and known CVRFs in children and adolescents with T1D. [ABSTRACT FROM AUTHOR]

Abstract Background Conflicting reports have been published on the sensitivity of spermatogenesis to capsaicin (CAP), the pungent ingredient of hot chili peppers. Here, the effect of CAP on germ cell survival was investigated by using two testis germ cell lines as a model. As CAP is a potent agonist of the transient receptor potential vanilloid receptor 1 (TRPV1) and no information was available of its expression in germ cells, we also studied the presence of TRPV1 in the cultured cells and in germ cells in situ. Methods The rat spermatogonial stem cell lines Gc-5spg and Gc-6spg were used to study the effects of different concentrations of CAP during 24 and 48 h. The response to CAP was first monitored by phase-contrast microscopy. As germ cells appear to undergo apoptosis in the presence of CAP, the activation of caspase 3 was studied using an anti activated caspase 3 antibody or by quantifying the amount of cells with DNA fragmentation using flow cytometry. Immunolocalization was done with an anti-TRPV1 antibody either with the use of confocal microscopy to follow live cell labeling (germ cells) or on Bouin fixed paraffin embedded testicular tissues. The expression of TRPV1 by the cell lines and germ cells was confirmed by Western blots. Results Initial morphological observations indicated that CAP at concentrations ranging from 150 uM to 250 uM and after 24 and 48 h of exposure, had deleterious apoptotic-like effects on both cell lines: A large population of the CAP treated cell cultures showed signs of DNA fragmentation and caspase 3 activation. Quantification of the effect demonstrated a significant effect of CAP with doses of 150 uM in the Gc-5spg cell line and 200 uM in the Gc-6spg cell line, after 24 h of exposure. The effect was dose and time dependent in both cell lines. TRPV1, the receptor for CAP, was found to be expressed by the spermatogonial stem cells in vitro and also by premeiotic germ cells in situ. Conclusion CAP adversely affects spermatogonial survival in vitro by inducing apoptosis to those cells and TRPV-1, a CAP receptor, may be involved in this effect as this receptor is expressed by mitotic germ cells.

Abstract Background The initial steps of stem Leydig cell differentiation into steroid producing progenitor cells are thought to take place independent of luteinizing hormone (LH), under the influence of locally produced factors such as leukaemia inhibitory factor (LIF), platelet derived growth factor A and stem cell factor. For the formation of a normal sized Leydig cell population in the adult testis, the presence of LH appears to be essential. Oncostatin M (OSM) is a multifunctional cytokine and member of the interleukin (IL)-6 family that also includes other cytokines such as LIF. In the rat OSM is highly expressed in the late fetal and neonatal testis, and may thus be a candidate factor involved in Leydig cell progenitor formation. Methods Interstitial cells were isolated from 13-day-old rat testes and cultured for 1, 3 or 8 days in the presence of different doses of OSM (range: 0.01 to 10 ng/ml) alone or in combination with LH (1 ng/ml). The effects of OSM and LH on cell proliferation were determined by incubating the cultures with [3H]thymidine or bromodeoxyuridine (BrdU). Developing progenitor cells were identified histochemically by the presence of the marker enzyme 3beta-hydroxysteroid dehydrogenase (3beta-HSD). Results OSM, when added at a dose of 10 ng/ml, caused a nearly 2-fold increase in the percentage of Leydig cell progenitors after 8 days of culture. Immunohistochemical double labelling experiments with 3beta-HSD and BrdU antibodies showed that this increase was the result of differentiation of stem Leydig cells/precursor cells and not caused by proliferation of progenitor cells themselves. The addition of LH to the cultures consistently resulted in an increase in progenitor formation throughout the culture period. Surprisingly, when OSM and LH were added together, the LH induced rise in progenitor cells was significantly inhibited after 3 and 8 days of culture. Conclusion Taken together, the results of the present study suggest that locally produced OSM may not only play a role in the regulation of Sertoli cell proliferation and the initiation of spermatogenesis but may also play a role in the regulation of Leydig cell progenitor formation by keeping the augmenting effects of LH on this process in abeyance.

The article focuses on the morphological differences of the Spur-thighed Tortoise found in eastern Turkey. The study was performed at the Nemrut Volcano and near Lake Van with 305 specimens, where most of them are adult tortoises. Results showed the morphological diversity of Spur-thighed Tortoise in terms of environmental factors like water supply and vegetation cover.

Seminoma cell lines, essential to the study of the biology of seminoma, do not exist. Tissue culture conditions for establishing such cell lines have to be developed. Under conventional culture conditions, seminoma cells usually die within the first 3 days after plating. The enhanced survival of rat gonocytes when cocultured with rat Sertoli cells in serum-free medium suggests that seminoma cells, the neoplastic counter parts of gonocytes, might benefit from the same conditions. Indeed, when cocultured with rat Sertoli cells in a serum-free medium, viable seminoma cells could be demonstrated on the 11th day of culture. This result is a significant improvement over the results with conventional methods. [J Natl Cancer Inst 83:1400–1403, 1991] [ABSTRACT FROM PUBLISHER]

Context: The pathophysiological mechanisms underlying the natural history of glucose intolerance and its fluctuations in subjects with cystic fibrosis (CF) are still unclear., Objective: To investigate the relationship between longitudinal changes in glucose tolerance and concomitant changes in the main parameters of insulin secretion/metabolism/action determining glucose regulation in CF subjects., Methods: Insulin sensitivity and glucose-stimulated insulin secretion (GSIS, a biomarker of beta cell functional mass), as estimated by the Oral Glucose Sensitivity Index (OGIS) and by a sophisticated mathematical model, respectively, and insulin clearance were assessed in 127 CF subjects, aged 10-25 years, who underwent two OGTT tests over at least 1-year follow-up period. Subjects were classified a posteriori as regressors (improved glucose tolerance), stable, or progressors (worsened glucose tolerance). The interplay between beta cell compensatory action and insulin sensitivity over time was analyzed by vector plots of insulin clearance adjusted GSIS (PCadj) versus OGIS., Results: OGIS decreased in progressors and stable. Insulin clearance decreased in both regressors and progressors. GSIS (beta cell functional mass) improved in regressors and worsened in progressors, whereas it did not change in stable. Vector plot analysis confirmed that glucose regulation changed differently in each group. Multinomial logistic regression analysis showed that baseline glucose tolerance and GSIS changes were the only significant predictors of the changes in glucose tolerance (p<0.02, R2Nagelkerke=0.55), whereas age, gender, z-BMI, CF genotypes, and baseline PCadj were not., Conclusions: In CF subjects, changes in beta cell functional mass are associated with favorable or detrimental changes of glucose tolerance over time., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Nitric oxide (NO) plays a key role in the processes leading to cervical softening prior to labor. Inducible nitric oxide synthase (iNOS) contributes most to the increased production of NO during labor, as demonstrated in the rat cervix, or at term pregnancy in women. Changes in expression of iNOS during late gestation have not yet been studied longitudinally in any species, because repeatedly taking biopsies could not be performed. iNOS mRNA (n = 6) and protein expression (n = 3) in serial cervical biopsies of pregnant pluriparous cows taken around days 225, 250, and 275 of pregnancy and within 1.5 hr after calving (d225, d250, d275 and parturition biopsies, respectively) were measured using quantitative RT-PCR and Western blotting. iNOS mRNA expression decreased from the d225 biopsy onwards, differences being significant between the d250 and d275 (P < 0.05) and between the d275 and parturition biopsies (P < 0.05). iNOS protein expression decreased from d225 to d250 onwards. Immunohistochemical analysis of biopsies showed, besides positive staining in endothelium and epithelium, which remained unchanged at different time points, that iNOS expressing cells in the connective tissue cells of early biopsies were predominantly spindle shaped (mostly smooth muscle cells and some fibroblasts). In the parturition biopsies, iNOS reactivity was mainly found in mononuclear leucocytes. These results lead us to suggest that iNOS from spindle shaped cells is involved in prepartum cervical ripening, while iNOS in mononuclear inflammatory cells may be important for local tissue repair mechanisms during postpartum cervical involution., ((c) 2006 Wiley-Liss, Inc.)

Several germ cell tumors that occur in adult men likely originate from gonocytes that are impaired in their development. To select candidate genes that are involved in the normal development of the gonocytes, we constructed a complementary DNA (cDNA) library from rat gonocytes as well as from single, paired, and aligned A spermatogonia (A(s), A(pr), and A(all) spermatogonia, respectively), their direct descendants. Five hundred gonocyte clones were differentially screened using both libraries. Successive verification by dot blot assays yielded 7 clones that were consistently highly abundant only in the gonocyte cDNA library. Also, in situ hybridization of these clones confirmed their differential expression. They encoded for, respectively, succinate dehydrogenase, ribosomal protein S15a, and the 65-kilodalton scaffolding subunit (a isoform) of protein phosphatase 2A. No clues regarding the nature of the remaining four clones could be found. Hence, using differential screening on both constructed cDNA libraries, we were able to select several genes that are interesting candidates for studying the molecular mechanisms of normal gonocyte development.