Dietary intake and glutamine-serine metabolism control pathologic vascular stiffness.

Perivascular collagen deposition by activated fibroblasts promotes vascular stiffening and drives cardiovascular diseases such as pulmonary hypertension (PH). Whether and how vascular fibroblasts rewire their metabolism to sustain collagen biosynthesis remains unknown. Here, we found that inflammation, hypoxia, and mechanical stress converge on activating the transcriptional coactivators YAP and TAZ (WWTR1) in pulmonary arterial adventitial fibroblasts (PAAFs). Consequently, YAP and TAZ drive glutamine and serine catabolism to sustain proline and glycine anabolism and promote collagen biosynthesis. Pharmacologic or dietary intervention on proline and glycine anabolic demand decreases vascular stiffening and improves cardiovascular function in PH rodent models. By identifying the limiting metabolic pathways for vascular collagen biosynthesis, our findings provide guidance for incorporating metabolic and dietary interventions for treating cardiopulmonary vascular disease.

Immobilization by 21 days of bed rest results in type II collagen degradation in healthy individuals.

OBJECTIVE: To investigate the effects of 21 days of bed rest immobilization (with and without exercise and nutrition interventions) on type II collagen biomarker concentrations in healthy individuals. DESIGN: Twelve healthy male participants (age 34.2 ± 8.3 years; body mass index 22.4 ± 1.7 kg/m²) were exposed to 6 days ambulatory baseline data collection (BDC), 21 days head-down-tilt bed rest (HDT, CON) + interventions (HDT + resistive vibration exercise (2 times/week, 25 minutes): RVE; HDT + RVE + whey protein (0.6 g/kg body weight/day) and bicarbonate supplementation (90 mmol KHCO3/day: NeX), and 6 days of re-ambulation (R) in a cross-over designed study. The starting HDT condition was randomized (CON-RVE-NEX, RVE-NEX-CON, NEX-CON-RVE). Blood and urine samples were collected before, during, and after HDT. Serum concentrations (s) of CPII, C2C, C1,2C, and urinary concentrations (u) of CTX-II and Coll2-1NO2 were measured. RESULTS: Twenty-one days of HDT resulted in increased sCPII (p < 0.001), sC2C (p < 0.001), and sC1,2C (p = 0.001) (highest increases: sCPII (+24.2% - HDT5), sC2C (+24.4% - HDT7), sC1,2C (+13.5% - HDT2). sC2C remained elevated at R+1 (p = 0.002) and R+6 (p < 0.001) compared to baseline. NeX led to lower sCPII (p < 0.001) and sC1,2C (p = 0.003) compared to CON. uCTX-II (second void and 24-hour urine) increased during HDT (p < 0.001, highest increase on HDT21: second void +82.8% (p < 0.001); 24-hour urine + 77.8% (p < 0.001). NeX resulted in lower uCTX-II concentrations in 24-hour urine (p = 0.012) compared to CON. CONCLUSIONS: Twenty-one days of bed rest immobilization results in type II collagen degradation that does not recover within 6 days of resuming ambulation. The combination of resistive vibration exercise and protein/bicarbonate supplementation minimally counteracted this effect.

Unraveling the Enigma of Perforating Itches: A Comprehensive Report of Reactive Perforating Collagenosis in Three Patients.

Reactive perforating collagenosis (RPC) is a rare dermatosis where dermal connective tissue erupts through the epidermis, resulting in diverse clinical manifestations such as umbilicated papules with crusting and excoriated nodules with central puncta. Associated with systemic disorders like diabetes mellitus, chronic kidney diseases, and autoimmune conditions, RPC's pathogenesis involves abnormal collagen metabolism, immune dysfunction, genetic predisposition, and environmental triggers. Histopathological examination reveals vertically oriented shallow cup-shaped invaginations containing degenerated collagen fibers, aiding diagnosis. Treatment includes managing underlying causes and utilizing options like topical corticoids, retinoids, and phototherapy, with a possibility of spontaneous regression and recurrence. This case report highlights the significance of considering RPC in patients with characteristic skin lesions and severe itching, emphasizing early recognition and accurate diagnosis to optimize patient care. Continued research and collaboration are crucial for improving outcomes in individuals affected by RPC.

Rotenone-exposure as cytofunctional aging model of human dermal fibroblast prior replicative senescence.

Rotenone (Ro), causes superoxide imbalance by inhibiting complex I of the mitochondrial electron transport chain, being able to serve as a model for functional skin aging by inducing cytofunctional changes in dermal fibroblasts prior to proliferative senescence. To test this hypothesis, we conducted an initial protocol to select a concentration of Ro (0.5, 1, 1.5, 2, 2.5, and 3 µM) that would induce the highest levels of the aging marker beta-galactosidase (ß-gal) in human dermal HFF-1 fibroblasts after 72 h of culture, as well as a moderate increase in apoptosis and partial G1 arrestment. We evaluated whether the selected concentration (1 µM) differentially modulated oxidative and cytofunctional markers of fibroblasts. Ro 1.0 µM increased ß-gal levels and apoptosis frequency, decreased the frequency of S/G2 cells, induced higher levels of oxidative markers, and presented a genotoxic effect. Fibroblasts exposed to Ro showed lower mitochondrial activity, extracellular collagen deposition, and fewer fibroblast cytoplasmic connections than controls. Ro triggered overexpression of the gene associated with aging (MMP-1), downregulation genes of collagen production (COL1A, FGF-2), and cellular growth/regeneration (FGF-7). The 1 µM concentration of Ro could serve as an experimental model for functional aging fibroblasts prior to replicative senescence. It could be used to identify causal aging mechanisms and strategies to delay skin aging events.

A randomized comparison of HBP versus RVP: Effect on left ventricular function and biomarkers of collagen metabolism.

BACKGROUND: Right ventricular pacing (RVP) can result in pacing-induced cardiomyopathy (PICM). It is unknown whether specific biomarkers reflect differences between His bundle pacing (HBP) and RVP and predict a decrease in left ventricular function during RVP. AIMS: We aimed to compare the effect of HBP and RVP on the left ventricular ejection fraction (LVEF) and to study how they affect serum markers of collagen metabolism. METHODS: Ninety-two high-risk PICM patients were randomized to HBP or RVP groups. Their clinical characteristics, echocardiography, and serum levels of transforming growth factor ß1 (TGF-ß1), matrix metalloproteinase 9 (MMP-9), suppression of tumorigenicity 2 interleukin (ST2-IL), tissue inhibitor of metalloproteinase 1 (TIMP-1), and galectin 3 (Gal-3) were studied before pacemaker implantation and six months later. RESULTS: Fifty-three patients were randomized to the HBP group and 39 patients to the RVP group. HBP failed in 10 patients, who crossed over to the RVP group. Patients with RVP had significantly lower LVEF compared to HBP patients after six months of pacing (-5% and -4% in as-treated and intention-to-treat analysis, respectively). Levels of TGF-ß1 after 6 months were lower in HBP than RVP patients (mean difference -6 ng/ml; P = 0.009) and preimplant Gal-3 and ST2-IL levels were higher in RVP patients, with a decline in LVEF ≥5% compared to those with a decline of <5% (mean difference 3 ng/ml and 8 ng/ml; P = 0.02 for both groups). CONCLUSION: In high-risk PICM patients, HBP was superior to RVP in providing more physiological ventricular function, as reflected by higher LVEF and lower levels of TGF-ß1. In RVP patients, LVEF declined more in those with higher baseline Gal-3 and ST2-IL levels than in those with lower levels.

Pomegranate natural extract Pomanox® positively modulates skin health-related parameters in normal and UV-induced photoaging conditions in Hs68 human fibroblast cells.

Skin photoaging is primarily caused by ultraviolet radiation and can lead to the degradation of skin extracellular matrix components, resulting in hyperpigmentation and skin elasticity loss. In this area, polyphenols have become of great interest because of their antioxidant, anti-inflammatory and antiaging properties. Here, we evaluated the effects of the pomegranate natural extract Pomanox® on skin health-related parameters in normal and UV-induced photoaging conditions in human fibroblast Hs68 cells. Moreover, the inhibitory effects of Pomanox® on tyrosinase activity were assessed. In normal conditions, Pomanox® significantly modulated collagen and hyaluronic acid metabolisms. In UV-exposed cells, both preventive and regenerative treatments with Pomanox® positively modulated hyaluronic acid metabolism and decreased ROS levels. However, only the preventive treatment modulated collagen metabolism. Finally, Pomanox® showed a marked inhibitory capacity of tyrosinase activity (IC50 = 394.7 µg/mL). The modulation of skin health-related parameters exhibited by Pomanox® open a wide range of potential applications of this product.

Blood donation improves skin aging through the reduction of iron deposits and the increase of TGF-ß1 in elderly skin.

Skin aging is characterized by a wide range of physiological and structural changes, including wrinkling, dyschromia, and roughness, as well as the reduction of dermal thickness and collagen content. Here, we showed that blood donation increased dermal thickness and collagen content and decreased the number of senescent cells in old mice. Transcriptomic and metabolomic studies revealed blood donation significantly altered aging-related pathways in the skin of old mice. Molecular genes analysis indicated blood donation decreased the expression of genes associated with inflammation such as Fols1, Cox-2, and IL-1ß, and increased the expression of collagen-associated genes including TGF-ß1, TGF-ß2, and Col3a1. The improvement of skin aging by blood donation was associated with the reduction of iron deposits and the increase of TGF-ß1 in elderly skin. Our results suggested that appropriate blood donation could promote collagen re-synthesis and improve skin aging.

Effects of faba bean (Vicia faba L.) on fillet quality of Yellow River carp (Cyprinus carpio) via the oxidative stress response.

In order to further explain the fillet texture improvement of Yellow River carp (Cyprinus carpio) fed with faba bean (Vicia faba L.), a three-month rearing trial was conducted to investigate fatty acid composition, antioxidant capacity, myofiber development, collagen deposition and transcriptome in white muscle of two farmed carp groups (One was fed only faba bean, the other was fed commercial diet). As a strong oxidant, faba bean changed fatty acids composition in white muscle, especially DHA and EPA, up-regulated the levels of reactive oxygen species (ROS) and down-regulated major antioxidant enzyme activities in the hepatopancreas and white muscle. Through the analysis of transcriptome and subsequent verification analysis, we speculated that the increase of ROS led to the decrease of myofiber diameter and collagen metabolism. This study provides a theoretical basis for further understanding the regulation of faba bean on fillet texture characteristic of Yellow River carp.

Mg-6Zn alloys promote the healing of intestinal anastomosis via TGF-ß/Smad signaling pathway in regulation of collagen metabolism as compared with titanium alloys.

There is a great clinical need for biodegradable materials. This study aimed to investigate the effects of Mg-6Zn and titanium alloy stapler nails on intestinal anastomosis healing mediated via the TGF-ß/Smad signaling pathway, as reflected in collagen metabolism in rabbits. Side-to-side ileo-ileostomy was performed with linear stapler loaded with the two nails. The results showed that no obvious postoperative complications such as abdominal infection and anastomotic leakage were observed. General observation and scanning electron microscope showed that Mg-6Zn alloy nails remained intact in the first week, degraded significantly in the second week, and were little left in the third week, while the titanium alloy nails showed intact substrate throughout the experimental period. Immunohistochemical analysis showed that the expression of TGF-ß1 in Mg-6Zn alloy group was higher than that in titanium alloy group after 1 week, but it increased slowly, arrived at a lower level in the third week. Collagen I showed an increased expression in Mg-6Zn alloy group, but decreased with time in titanium alloy group. An enhanced expression of collagen III in Mg-6Zn alloy group in the first week but much lower in the third week as compared to the titanium alloy group. The expression of smad2 in Mg-6Zn alloy group maintained a steady level, while in titanium alloy group it showed a general upward trend. The expression of smad3 in both groups held steady after 2 weeks, then in the third week, it showed a strong uptrend in Mg-6Zn alloy group, while decreased immediately in titanium alloy group. Our findings suggest that Mg-6Zn alloy nails degraded significantly within 3 weeks and could provide stability of intestinal anastomosis in the reconstruction of intestinal tract. TGF-ß/Smad signaling pathway may play a role in regulation of baseline collagen synthesis throughout the process.

Advances in bone turnover markers.

Bone fragility fractures remain an important worldwide health and economic problem due to increased morbidity and mortality. The current methods for predicting fractures are largely based on the measurement of bone mineral density and the utilization of mathematical risk calculators based on clinical risk factors for bone fragility. Despite these approaches, many bone fractures remain undiagnosed. Therefore, current research is focused on the identification of new factors such as bone turnover markers (BTM) for risk calculation. BTM are a group of proteins and peptides released during bone remodeling that can be found in serum or urine. They derive from bone resorptive and formative processes mediated by osteoclasts and osteoblasts, respectively. Potential use of BTM in monitoring these phenomenon and therefore bone fracture risk is limited by physiologic and pathophysiologic factors that influence BTM. These limitations in predicting fractures explain why their inclusion in clinical guidelines remains limited despite the large number of studies examining BTM.

miR-150-5p affects AS plaque with ASMC proliferation and migration by STAT1.

We explore miR-150-5p in atherosclerosis (AS). The AS model was constructed using Apo E-/- mice with an injection of the miR-150-5p mimic or an inhibitor. Pathological characteristics were assessed using Oil red O staining and Masson staining. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot were used to analyze the expressions of microRNA-150-5p (miR-150-5p), STAT1, α-SMA (α-smooth muscle actin) and proliferating cell nuclear antigen (PCNA). Targetscan and dual-luciferase reporter assay were used to analyze the interaction between miR-150-5p and STAT1. The viability, migration, cell cycle and α-SMA and PCNA expressions in oxidized low-density lipoprotein (ox-LDL)-stimulated primary human aortic smooth muscle cells (ASMCs) were assessed using molecular experiments. miR-150-5p was reduced in both AS mice and ox-LDL-stimulated human aortic smooth muscle cells but STAT1 had the opposite effect. The miR-150-5p inhibitor alleviated the increase of lipid plaque and reduced collagen accumulation in the aortas during AS. Upregulation of α-SMA and PCNA was reversed by miR-150-5p upregulation. STAT1 was targeted by miR-150-5p, and overexpressed miR-150-5p weakened the ox-LDL-induced increase of viability and migration abilities and blocked cell cycle in ASMCs, but overexpressed STAT1 blocked the effect of the miR-150-5p mimic. This paper demonstrates that miR-150-5p has potential as a therapeutic target in AS, with plaque stabilization by regulating ASMC proliferation and migration via STAT1.

Vulvar Lichen Sclerosus from Pathophysiology to Therapeutic Approaches: Evidence and Prospects.

Vulvar lichen sclerosus (VLS) is a chronic, distressing, inflammatory disease with an enormous impact on quality of life. Treatment goals are relieving symptoms, reversing signs and preventing anatomical changes. Despite the availability of numerous therapeutic options, treatment outcome may not be entirely satisfactory and a definitive cure does not exist. This may be due to the fact that the exact VLS etiopathogenesis remains unknown. The objectives of this paper were to review the most up-to-date knowledge on VLS etiopathogenesis and to consider the available therapies through the lens of a plausible pathogenetic model. An electronic search on both VLS etiopathogenesis and its treatment was performed using the National Library of Medicine PubMed database. Based on current knowledge, it is conceivable that various, heterogeneous environmental factors acting on a genetic background trigger an autoimmune, Th-1 response, which leads to a chronic inflammatory state. This, in turn, can determine both tissue and micro-vascular injury and activation of signaling pathways involved in fibroblast and collagen metabolism. This pathogenetic sequence may explain the effectiveness of anti-inflammatory treatments, mostly topical corticosteroids, in improving VLS clinical-pathological changes. Further deepening of the disease pathways will presumably allow key mediators to become new therapeutic targets and optimize the available treatments.

Corneal crosslinking efficacy in patients with keratoconus under 18 years of age / Eficácia do crosslinking corneano em portadores de ceratocone com idade inferior a 18 anos

ABSTRACT Purpose: Keratoconus presents certain specificities in pediatric patients compared with adults. The greatest challenge is because the disease is typically more severe and progresses faster in children. This retrospective study aimed to report crosslinking procedure in patients under 18 years of age and their follow-up for at least 24 months after the procedure. Methods: Overall, 12 eyes from 10 patients were studied and data, such as visual acuity with and without correction, maximum keratometry, corneal thickness, foveal thickness, and endothelial microscopy, were assessed at both preoperative and postoperative visits. Corneal crosslinking was performed in all patients. Results: A tendency toward reduced Kmax and improved Corrected Distance Visual Acuity at all postoperative moments. Only one of the 12 eyes exhibited increased Kmax of more than 1 D during a time frame longer than 12 months. Regarding pachymetry, a tendency for corneal thinning was observed in the first four months after surgery. Conclusion: Encouraging results were obtained regarding the stabilization of the disease, progression, and procedural safety, corroborating to other authors' findings. The significance of early diagnosis and short-term follow-up were highlighted.

RESUMO Objetivo: O ceratocone na população pediátrica apresenta algumas particularidades em relação à população adulta. O maior desafio é devido à doença ser geralmente mais severa e rapidamente progressiva em crianças. Métodos: Este artigo utiliza uma análise retrospectiva para relatar o uso do crosslinking em jovens menores de 18 anos e sua evolução pelo menos 24 meses após o procedimento. Foram estudados 12 olhos de 10 pacientes, e dados como acuidade visual com e sem correção, ceratometria máxima, espessura corneana, espessura foveal e microscopia endotelial avaliados no pré e pós-operatórios. O crosslinking corneano foi realizado em todos os pacientes pelo mesmo cirurgião. Resultados: Observou-se uma tendência de redução do valor do Kmax e melhora da acuidade visual corrigida em todos os momentos de pós operatório. Com relação à paquimetria, observou-se afinamento corneano do ponto mais fino, nos primeiros quatro meses de pós-operatório. Conclusão: Resultados encorajadores foram obtidos com relação à estabilização da doença, progressão e segurança do procedimento, corroborando com as conclusões de outros autores. A importância do diagnóstico precoce e do acompanhamento a curto prazo do paciente deve ser destacada.

Collagen metabolism as a regulator of proline dehydrogenase/proline oxidase-dependent apoptosis/autophagy.

Recent studies on the regulatory role of amino acids in cell metabolism have focused on the functional significance of proline degradation. The process is catalysed by proline dehydrogenase/proline oxidase (PRODH/POX), a mitochondrial flavin-dependent enzyme converting proline into ∆1-pyrroline-5-carboxylate (P5C). During this process, electrons are transferred to electron transport chain producing ATP for survival or they directly reduce oxygen, producing reactive oxygen species (ROS) inducing apoptosis/autophagy. However, the mechanism for switching survival/apoptosis mode is unknown. Although PRODH/POX activity and energetic metabolism were suggested as an underlying mechanism for the survival/apoptosis switch, proline availability for this enzyme is also important. Proline availability is regulated by prolidase (proline supporting enzyme), collagen biosynthesis (proline utilizing process) and proline synthesis from glutamine, glutamate, α-ketoglutarate (α-KG) and ornithine. Proline availability is dependent on the rate of glycolysis, TCA and urea cycles, proline metabolism, collagen biosynthesis and its degradation. It is well established that proline synthesis enzymes, P5C synthetase and P5C reductase as well as collagen prolyl hydroxylases are up-regulated in most of cancer types and control rates of collagen biosynthesis. Up-regulation of collagen prolyl hydroxylase and its exhaustion of ascorbate and α-KG may compete with DNA and histone demethylases (that require the same cofactors) to influence metabolic epigenetics. This knowledge led us to hypothesize that up-regulation of prolidase and PRODH/POX with inhibition of collagen biosynthesis may represent potential pharmacotherapeutic approach to induce apoptosis or autophagic death in cancer cells. These aspects of proline metabolism are discussed in the review as an approach to understand complex regulatory mechanisms driving PRODH/POX-dependent apoptosis/survival.

Expression of COX-2 and Nrf2/GPx3 in the anterior vaginal wall tissues of women with pelvic organ prolapse.

PURPOSE: To evaluate COX-2 and Nrf2/GPx3 expressions in the lamina propria of the anterior vaginal wall tissues of women with and without pelvic organ prolapse (POP). METHODS: Tissue samples of anterior vaginal wall were examined using HE staining, immuohistochemical staining and Western blot for the expressions of COX-2/PGE2, Nrf2/GPx3, MMP2, TIMP1, collagen I and collagen III (n = 35, per group). RESULTS: Compared with control group, collagen fibers of the anterior vaginal wall were disorganized and discontinuous. Expressions of Nrf2, GPx3, TIMP1, collagen I and collagen III were found significantly lower in POP group (P < 0.05); while, expressions of COX-2, PGE2, and MMP2 were found significantly higher in POP group (P < 0.05). Statistically significant correlations of COX-2 and Nrf2/GPx3 were showed (P < 0.01). CONCLUSION: We found that the interaction between inflammation and oxidative stress was closely related to the development of POP. This study demonstrates that COX-2 and Nrf2 pathways may be involved in pathogenesis of POP, as promising potential therapeutic targets and agents.

[Rehabilitation of orphan diseases in adulthood: osteogenesis imperfecta]. / Rehabilitation seltener Erkrankungen im Erwachsenenalter: Osteogenesis imperfecta.

Osteogenesis imperfecta (brittle bone disease) is an orphan disease caused by a genetic mutation in collagen metabolism. Bone fractures are the most common symptoms; however, the clinical manifestation can vary widely. Additional features can include blue sclera, dwarfism, bone deformities, muscular weakness, scoliosis, hearing loss and hypermobility of joints. Most patients show a reduction of skeletal function. This leads to an increased risk of being unable to continue their former work and to participate in social life. A comprehensive treatment includes drug therapy, surgery and rehabilitation. This article gives an overview of the current status of rehabilitation in adult patients with osteogenesis imperfecta.

Sevoflurane prevents vulnerable plaque disruption in apolipoprotein E-knockout mice by increasing collagen deposition and inhibiting inflammation.

BACKGROUND: Sevoflurane may reduce the occurrence of major adverse cardiovascular events (MACCEs) in surgical patients, although the mechanisms are poorly understood. We hypothesised that sevoflurane stabilises atherosclerotic plaques by inhibiting inflammation and enhancing prolyl-4-hydroxylase α1 (P4Hα1), the rate-limiting subunit for the P4H enzyme essential for collagen synthesis. METHODS: We established a vulnerable arterial plaque model in apolipoprotein E-knockout mice (ApoE-/-) fed a high-fat diet that underwent daily restraint/noise stress, with/without a single prior exposure to sevoflurane for 6 h (1-3%; n=30 per group). In vitro, smooth muscle cells (SMCs) were incubated with tumour necrosis factor-alpha in the presence/absence of sevoflurane. Immunohistochemistry, immunoblots, and mRNA concentrations were used to quantify the effect of sevoflurane on plaque formation, expression of inflammatory cytokines, P4Hα1, and collagen subtypes in atherosclerotic plaques or isolated SMCs. RESULTS: In ApoE-/- mice, inhalation of sevoflurane 1-3% for 6 h reduced the aortic plaque size by 8-29% in a dose-dependent manner, compared with control mice that underwent restraint stress alone (P<0.05); this was associated with reduced macrophage infiltration and lower lipid concentrations in plaques. Sevoflurane reduced gene transcription and protein expression levels of pro-inflammatory cytokines (≥69-75%; P<0.05) and matrix metalloproteinases (≥39-65%; P<0.05) at both gene transcription and protein levels, compared with controls. Sevoflurane dose dependently increased Types I and III collagen deposition through enhanced protein expression of P4Hα1, both in vivo and in vitro (0.7-3.3-fold change; P<0.05). CONCLUSIONS: Sevoflurane dose dependently promotes plaque stabilisation and decreases the incidence of plaque disruption in ApoE-/- mice by increasing collagen deposition and inhibiting inflammation. These mechanisms may contribute to sevoflurane reducing MACCE.

The peptide compound urantide regulates collagen metabolism in atherosclerotic rat hearts and inhibits the JAK2/STAT3 pathway.

The aim of the present study was to investigate the effect of urantide on collagen metabolism in the hearts of rats with atherosclerosis (AS) by evaluating the expression of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway constituents. Urantide was delivered to rats with AS via tail vein injection for 3, 7 and 14 days. Serological indicators were identified by an automated biochemical analyzer. Histomorphological changes in the cardiac tissue of rats were observed by pathological staining techniques. The expression of genes and proteins was assessed using reverse transcription­quantitative PCR and western blot analysis, respectively. Localization of proteins was detected by immunofluorescence. Overexpression of urotensin II (UII) and its receptor, G protein­coupled receptor 14 (GPR14), was observed in the hearts of rats with AS and the expression of both proteins significantly declined after urantide administration. Triglyceride, total cholesterol, low­density lipoprotein, high­density lipoprotein and calcium levels were improved in rats with AS following treatment with urantide. Notably, urantide was able to antagonize the UII/GPR14 system. Urantide treatment resulted in markedly decreased expression levels of matrix metalloproteinase 2 (MMP­2), collagen type I/III, and genes and proteins in the JAK2/STAT3 pathway. By contrast, TIMP metallopeptidase inhibitor 2 (TIMP­2) levels were increased. In addition, the MMP­2/TIMP­2 protein ratio was significantly decreased in rats treated with urantide compared with AS rats with no urantide treatment. Constituents of the JAK2/STAT3 pathway and collagen type I/III were found to be localized in the diseased tissue and blood vessels of the hearts of rats with AS. In conclusion, urantide was able to effectively block the UII/GPR14 system by regulating the JAK2/STAT3 pathway and collagen metabolism. Inhibition of the UII/GPR14 system may prevent and potentially treat atherosclerotic myocardial fibrosis. Based on the current results, it was hypothesized that collagen metabolism may be associated with the JAK2/STAT3 pathway.

Age- and sex-dependent differences in extracellular matrix metabolism associate with cardiac functional and structural changes.

Age-related remodeling of the heart causes structural and functional changes in the left ventricle (LV) that are associated with a high index of morbidities and mortality worldwide. Some cardiac pathologies in the elderly population vary between genders revealing that cardiac remodeling during aging may be sex-dependent. Herein, we analyzed the effects of cardiac aging in male and female C57Bl/6 mice in four age groups, 3, 6, 12, and 18 month old (n = 6-12 animals/sex/age), to elucidate which age-related characteristics of LV remodeling are sex-specific. We focused particularly in parameters associated with age-dependent remodeling of the LV extracellular matrix (ECM) that are involved in collagen metabolism. LV function and anatomical structure were assessed both by conventional echocardiography and speckle tracking echocardiography (STE). We then measured ECM proteins that directly affect LV contractility and remodeling. All data were analyzed across ages and between sexes and were directly linked to LV functional changes. Echocardiography confirmed an age-dependent decrease in chamber volumes and LV internal diameters, indicative of concentric remodeling. As in humans, animals displayed preserved ejection fraction with age. Notably, changes to chamber dimensions and volumes were temporally distinct between sexes. Complementary to the traditional echocardiography, STE revealed that circumferential strain rate declined in 18 month old females, compared to younger animals, but not in males, suggesting STE as an earlier indicator for changes in cardiac function between sexes. Age-dependent collagen deposition and expression in the endocardium did not differ between sexes; however, other factors involved in collagen metabolism were sex-specific. Specifically, while decorin, osteopontin, Cthrc1, and Ddr1 expression were age-dependent but sex-independent, periostin, lysyl oxidase, and Mrc2 displayed age-dependent and sex-specific differences. Moreover, our data also suggest that with age males and females have distinct TGFß signaling pathways. Overall, our results give evidence of sex-specific molecular changes during physiological cardiac remodeling that associate with age-dependent structural and functional dysfunction. These data highlight the importance of including sex-differences analysis when studying cardiac aging.

Deficiency of NONO is associated with impaired cardiac function and fibrosis in mice.

Non-POU-domain-containing octamer-binding protein (NONO), a component of multifunctional Drosophila behavior/human splicing (DBHS) family, plays an important role in regulating glucose and fat metabolism, circadian cycles, cell division, collagen formation and fibrosis. Dysfunctional variants of NONO have been described as the cause of congenital heart defects in males. However, the effects of NONO deficiency on the ventricular function and cardiac fibrosis as well as the related mechanisms are not clear. In the present study, we aimed to reveal the overall phenotypes, cardiac function and fibroblasts in NONO knockout (NONO KO) mice compared with the wild-type (WT) male littermates. The results showed that the birth rate of NONOgt/0 mice was much lower than their WT male littermates at the time of weaning. The body weight of NONOgt/0 mice was 19% lower than that of WT male littermates (27.2 ±â€¯1.49 g vs. 22.01 ±â€¯1.20 g, P < .001). NONO KO mice exhibited continuous higher mortality from birth to a year later (P < .05). Compared with those in the WT mice, the heart weight was lower(142.0 ±â€¯8.7 mg vs. 179.0 ±â€¯10.4 mg, P < .001), the heart weight to body weight ratio (HW/BW) was similar, the E/A ratio was higher (1.80 ±â€¯0.47 vs. 1.44 ±â€¯0.26, P < .05), and the left ventricular end diastolic diameter (LVEDd) was significantly lower (2.72 ±â€¯0.51 mm vs.3.54 ±â€¯0.43 mm, P < .001) in the NONO KO mice. We also found excessive matrix deposition in vivo. In vitro, NONO deficiency led to fibroblasts hyperproliferation, while migration was inhibited, which would induce collagen maturation and deposition. Conversely, overexpression of NONO inhibited fibroblasts proliferation and increased migration which reduced collagen deposition. RNA-seq of cardiac fibroblasts further indicated that NONO deficiency upregulated the cell cycle regulators, which included cyclin B2, the origin recognition complex 1 (ORC1) and cell division cycle 6 (CDC6), while downregulated the migration regulators, which included myosins, integrin and coagulation factor II. Overexpression of NONO further verified the effects of these indicators. In conclusion, our study demonstrated that NONO deficiency was associated with developing heart defects in mice. Hyperproliferation of cardiac fibroblasts with dramatically excessive collagen secretion might be the cause of heart defects of NONO KO mice.