Exploring the link between vitamin D deficiency and obstructive sleep apnea: A comprehensive review.

Despite the high prevalence and significant health burden of obstructive sleep apnea (OSA), its underlying pathophysiology remains incompletely understood. This comprehensive review explores the emerging connection between vitamin D deficiency and OSA, discusses potential mechanisms underlying this association, and explores the therapeutic implications of these findings. Recent research has consistently highlighted the high incidence of vitamin D deficiency among patients with OSA, which often occurs independently of geographical location. This suggests that factors beyond lack of sunlight exposure may be involved. This review also discusses how reduced vitamin D may be associated with more severe manifestations of OSA. In addition, it explores the potentiality of using vitamin D supplements as a therapeutic strategy for OSA, noting that some studies have found improvements in sleep quality and a reduction in OSA severity. Potential mechanisms are proposed, including the role of vitamin D deficiency in promoting inflammation, oxidative stress, hypoxia, impairing immune function, muscle function, and gene polymorphism of vitamin D receptors, all of which could contribute to the pathogenesis of obstructive sleep apnea. The paper underscores the need for future research to validate these observations, to determine optimal vitamin D supplementation dosage and duration, to explore potential side effects and risks, and to investigate potential interactions with other treatments.

Dietary bile acids improve breast muscle growth in chickens through FXR/IGF2 pathway.

It is a common practice to provide fast-growing broilers with high-fat diets in the context of integrated farms in Northeast China. Therefore, fat digestion, absorption, and utilization efficiency are critical for broiler meat production. Bile acids (BA) promote fat digestion and absorption, but whether and how BA affects muscle growth in broilers remains unclear. In this study, 1-day-old broilers were fed diets containing varying levels of crude fat (low, medium, and high) with or without BA supplementation for 42 d. Chickens fed a high-fat diet supplemented with BA exhibited significantly (P < 0.05) higher body weight (BW) at 21 d and average daily gain (ADG) during the first 21 d compared to the other groups. Throughout the entire experiment, feed conversion rate (FCR) was significantly (P < 0.05) lower in the high-fat group without the addition of BA, which was further decreased (P < 0.05) with BA supplementation. The improved growth performance in the BA-supplemented high-fat group was associated with significantly (P < 0.05) higher lipase activity in the small intestine chyme, a decreased trend (P = 0.06) in abdominal fat ratio, and significantly (P < 0.05) higher breast muscle mass. Histological analysis revealed significant (P < 0.05) increases in myofiber diameter, cross-sectional area, and RNA and DNA concentrations in the breast muscle of BA-supplemented broilers on the high-fat diet. Additional histological analysis further revealed significant (P < 0.05) enhancements in myofiber diameter, cross-sectional area, and RNA and DNA concentrations within the breast muscles of broilers supplemented with BA and a high-fat diet. The increased insulin-like growth factor 2 (IGF2) in the breast muscle of broilers fed a BA-supplemented high-fat diet correlated with significantly (P < 0.05) increased farnesoid X factor (FXR) protein expression and binding to the IGF2 promoter. These results suggest that dietary BA supplementation improves FCR and breast muscle growth in broilers fed a high-fat diet, potentially through the FXR-mediated IGF2 pathway.

Discovery of novel antagonists targeting the DNA binding domain of androgen receptor by integrated docking-based virtual screening and bioassays.

Androgen receptor (AR), a ligand-activated transcription factor, is a master regulator in the development and progress of prostate cancer (PCa). A major challenge for the clinically used AR antagonists is the rapid emergence of resistance induced by the mutations at AR ligand binding domain (LBD), and therefore the discovery of novel anti-AR therapeutics that can combat mutation-induced resistance is quite demanding. Therein, blocking the interaction between AR and DNA represents an innovative strategy. However, the hits confirmed targeting on it so far are all structurally based on a sole chemical scaffold. In this study, an integrated docking-based virtual screening (VS) strategy based on the crystal structure of the DNA binding domain (DBD) of AR was conducted to search for novel AR antagonists with new scaffolds and 2-(2-butyl-1,3-dioxoisoindoline-5-carboxamido)-4,5-dimethoxybenzoicacid (Cpd39) was identified as a potential hit, which was competent to block the binding of AR DBD to DNA and showed decent potency against AR transcriptional activity. Furthermore, Cpd39 was safe and capable of effectively inhibiting the proliferation of PCa cell lines (i.e., LNCaP, PC3, DU145, and 22RV1) and reducing the expression of the genes regulated by not only the full-length AR but also the splice variant AR-V7. The novel AR DBD-ARE blocker Cpd39 could serve as a starting point for the development of new therapeutics for castration-resistant PCa.

Efficacy of gecko polysaccharide on suppressed immune response induced by cyclophosphamide in mice.

OBJECTIVE: To evaluate the efficacy of gecko polysaccharide on the cyclophosphamide-induced suppressed immune response in mice. METHODS: Polysaccharides were extracted from fresh gecko for the first time using an orthogonal method and protein was removed using Sevag reagent (chloroform:N-butanol, 5:1, v/v). The gecko polysaccharide (GPCE) content was determined by the phenol-concentrated sulfuric acid method. An immunocompromised mouse model was established by intraperitoneally injecting cyclophosphamide at 100 mg/kg into 48 mice. The effects of GPCE on immune regulation in mice were assessed by a thymus-spleen index, serum hemolysin levels, and the proliferation of splenic lymphocytes. Spleen cell CD4+, CD8+, and the CD4+/CD8+ ratio were evaluated by flow cytometry and the tumor necrosis factor-α (TNF-α) levels were measured by ELISA. RESULTS: The optimal extraction process for gecko polysaccharide included a 1:20 ratio of material to liquid (v/v), an extraction temperature of 60 ℃ and a time of 2 h. The polysaccharide content of the extract was 65.74%. GPCE was analyzed by HPLC and primarily contained glucose and small amounts of mannose, rha, and gal. Compared with the model, the thymus index, the spleen index were indices for GPCE increased with dose, whereas the high and medium groups exhibited significant differences (P < 0.05, P < 0.01). Higher doses of GPCE increased serum TNF-α levels and there was a significant difference between the medium and high GPCE doses and the model (P < 0.05, P < 0.01); The number of CD4+ cells and the CD4+/CD8+ ratio in the gecko polysaccharide group were increased (P < 0.05) and there was no statistical difference in the number of CD8+ cells in the gecko polysaccharide group (P > 0.05); The high GPCE dose significantly increased the level of serum hemolysin (P < 0.01). CONCLUSIONS: Gecko polysaccharide significantly improved the suppressed immune response induced by cyclophosphamide in mice and promoted the secretion of tumor necrosis factor. The mechanism of gecko polysaccharide as an antitumor agent warrants further study.

Selenium-GPX4 axis protects follicular helper T cells from ferroptosis.

Follicular helper T (TFH) cells are a specialized subset of CD4+ T cells that essentially support germinal center responses where high-affinity and long-lived humoral immunity is generated. The regulation of TFH cell survival remains unclear. Here we report that TFH cells show intensified lipid peroxidation and altered mitochondrial morphology, resembling the features of ferroptosis, a form of programmed cell death that is driven by iron-dependent accumulation of lipid peroxidation. Glutathione peroxidase 4 (GPX4) is the major lipid peroxidation scavenger and is necessary for TFH cell survival. The deletion of GPX4 in T cells selectively abrogated TFH cells and germinal center responses in immunized mice. Selenium supplementation enhanced GPX4 expression in T cells, increased TFH cell numbers and promoted antibody responses in immunized mice and young adults after influenza vaccination. Our findings reveal the central role of the selenium-GPX4-ferroptosis axis in regulating TFH homeostasis, which can be targeted to enhance TFH cell function in infection and following vaccination.

Can Long-Term Regular Practice of Physical Exercises Including Taichi Improve Finger Tapping of Patients Presenting With Mild Cognitive Impairment?

Background: Mild cognitive impairment (MCI) is a brain disease with both anatomical and functional alterations. There is clear evidence that individuals that are diagnosed with MCI have a high risk to develop dementia in the next 2-5 years compared to an age-matched population with a non-MCI diagnosis. The present study aimed to investigate whether the finger tapping frequency of patients with MCI was different from that of healthy individuals without MCI, and whether Tai Chi, a traditional Chinese movement discipline, could improve the finger tapping frequency of MCI patients. Methods: The study population consisted of subjects of ≥50 years of age. Group one included 40 subjects without exercise habits from communities of Yangpu District in Shanghai, and group two included 60 subjects from a Tai Chi class in Shanghai Elderly University of Huangpu District. The Montreal Cognitive Assessment (MoCA) and a finger tapping test were conducted to assess the finger tapping frequency of all subjects. Results: The MoCA score of MCI subjects was significantly lower compared to subjects without MCI (P < 0.01), and was not influenced by age, weight, or height. The finger tapping frequency of MCI subjects' left hands was significantly lower compared to that of healthy subjects without MCI (P < 0.01), and a similar trend was observed for the subjects' right hand. The MoCA score of MCI subjects in the Tai Chi class was significantly lower than that of healthy subjects without MCI (P < 0.01), which was not influenced by age, weight or height. The finger tapping frequency of MCI subjects' right hands was lower compared to that of healthy subjects in the Tai Chi class without MCI (P < 0.05), but no significant difference regarding the finger tapping frequency of the left hand was observed. Conclusion: These findings suggested that finger tapping frequency of MCI subjects was significantly lower compared to normal subjects without MCI, and long-term Tai Chi exercise could reduce this significant difference. Moreover, there was no significant difference between groups for the subjects' non-dominant (left) hand.

Nano-sized Al2O3 particle-induced autophagy reduces osteolysis in aseptic loosening of total hip arthroplasty by negative feedback regulation of RANKL expression in fibroblasts.

Aseptic loosening is mainly caused by wear debris generated by friction that can increase the expression of receptor activation of nuclear factor (NF)-κB (RANKL). RANKL has been shown to support the differentiation and maturation of osteoclasts. Although autophagy is a key metabolic pathway for maintaining the metabolic homeostasis of cells, no study has determined whether autophagy induced by Al2O3 particles is involved in the pathogenesis of aseptic loosening. The aim of this study was to evaluate RANKL levels in patients experiencing aseptic loosening after total hip arthroplasty (THA) and hip osteoarthritis (hOA) and to consequently clarify the relationship between RANKL and LC3II expression. We determined the levels of RANKL and autophagy in fibroblasts treated with Al2O3 particles in vitro while using shBECN-1 interference lentivirus vectors to block the autophagy pathway and BECN-1 overexpression lentivirus vectors to promote autophagy. We established a novel rat model of femoral head replacement and analyzed the effects of Al2O3 particles on autophagy levels and RANKL expression in synovial tissues in vivo. The RANKL levels in the revision total hip arthroplasty (rTHA) group were higher than those in the hOA group. In patients with rTHA with a ceramic interface, LC3II expression was high, whereas RANKL expression was low. The in vitro results showed that Al2O3 particles promoted fibroblast autophagy in a time- and dose-dependent manner and that RANKL expression was negatively correlated with autophagy. The in vivo results further confirmed these findings. Al2O3 particles induced fibroblast autophagy, which reduced RANKL expression. Decreasing the autophagy level promoted osteolysis and aseptic prosthetic loosening, whereas increasing the autophagy level reversed this trend.

[Effects of drought stress on C, N and P stoichiometry of Ulmus pumila seedlings in Horqin sandy land, China.] / å¹²æ—±èƒè¿«å¯¹ç§‘å°”æ²æ²™åœ°æ¦†æ ‘å¹¼è‹—C、N、P化学计量特征的影响.

To understand the effects of drought stress on C, N and P stoichiometry in different organs of Ulmus pumila, U. pumila seedlings were grown under suitable water level, mild, moderate and serious water stress treatment, i.e., 80%, 65%, 50% and 35% of field water holding capacity. The results showed that drought stress increased C content in leaves, stems, coarse and fine roots, N content in leaves, stems and coarse roots, and P content in fine roots, but decreased P content in leaves, stems and coarse roots. Moreover, C:N in leaves and stems decreased, while C:P and N:P in leaves, stems and coarse roots increased and in fine roots reduced in response to drought stresses. There were significant correlations of C content among different organs, while N content was not correlated with P content in all organs. Soil water content was negatively related to C content in all organs, N content in leaves, P content and C:N in fine roots, C:P and N:P in leaves, stems and coarse roots. There were positive relationships between the soil water content and N content in fine roots, P content in leaves, stems and coarse roots, C:P and N:P in fine roots. These findings indicated that the absorption and upward translocation of N and P of U. pumila seedlings were influe-nced by drought stress. Nitrogen limitation for the growth of U. pumila seedlings was found. With the increases of drought stress, however, P limitation was gradually enhanced.

Maternal and embryonic exposure to the water soluble fraction of crude oil or lead induces behavioral abnormalities in zebrafish (Danio rerio), and the mechanisms involved.

The water-soluble fraction (WSF) of crude oil plays an important role in the toxicity of crude oil in aquatic environments. Heavy metals, such as lead (Pb) are also important environmental contaminants, which can reach aquatic systems via the effluents of industrial, urban and mining sources. In the present study, we investigated whether maternal and embryonic exposure to the WSF (5, 50 µg/L) or Pb (10, 100 µg/L) could induce behavioral abnormalities in zebrafish. Our results showed that maternal and embryonic exposure to the WSF (5, 50 µg/L) and Pb (10, 100 µg/L) induced swimming activity alterations in larval and juvenile zebrafish. In 15 days post-fertilization (dpf) larval zebrafish, the distance moved was significantly increased in the groups treated with the WSF (5, 50 µg/L), but the angular velocity and turn angle were decreased after treatment with the WSF (5, 50 µg/L) or Pb (10, 100 µg/L). In 30 dpf juvenile zebrafish, the distance moved was markedly decreased in both groups treated with the WSF (5, 50 µg/L) and the Pb (10 µg/L) group, but the percentage of zebrafish moving up and the inter-fish distance of two juvenile fish were increased after treatment with the WSF (5, 50 µg/L) or Pb (10, 100 µg/L). Maternal and embryonic exposure to the WSF (5, 50 µg/L) or Pb (10, 100 µg/L) likely impaired the brain neurons growth and induced behavioral abnormalities in the larval and juvenile zebrafish. Furthermore, the expressions of some key genes, which were associated with calcium channels, behavioral development or the metabolism of environmental contaminants, were changed.

Increasing expression of substance P and calcitonin gene-related peptide in synovial tissue and fluid contribute to the progress of arthritis in developmental dysplasia of the hip.

INTRODUCTION: Developmental dysplasia of the hip (DDH) is a common musculoskeletal disorder that has pain and loss of joint function as major pathological features. In the present study, we explored the mechanisms of possible involvement and regulation of substance P (SP) and calcitonin gene-related peptide (CGRP) in the pathological and inflammatory processes of arthritis in DDH. METHODS: Blood, synovial tissue and fluid samples were collected from patients diagnosed with different severities of DDH and from patients with femoral neck fracture. Levels of SP, CGRP and inflammatory cytokines in synovium and synovial fluid (SF) in the different groups were evaluated by immunohistochemistry, real-time PCR and enzyme-linked immunosorbent assay (ELISA). Correlations between neuropeptides and inflammatory cytokines in SF were evaluated by partial correlation analysis. The proinflammatory effects of SP and CGRP on synoviocytes obtained from patients with moderate DDH were investigated in vitro by real-time PCR and ELISA. The mechanisms of those effects were evaluated by Western blot analysis and nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) DNA binding assay. RESULTS: Significantly increased levels of neuropeptides and inflammatory cytokines were observed in synovium and SF from patients in the severe DDH group compared with the moderate DDH and control groups. In moderate DDH samples, SP in SF correlated with tumor necrosis factor (TNF)-α, and CGRP in SF correlated with TNF-α and interleukin (IL)-10. In the severe DDH group, SP in SF correlated with interleukin (IL)-1ß, TNF-α and IL-10. CGRP in SF correlated with TNF-α. Additionally, SP might have had obvious proinflammatory effects on synoviocytes through the activation of NF-κB. CONCLUSIONS: The upregulation of SP and CGRP in synovium and SF might participate in the inflammatory process of arthritis in DDH. The activation of the NF-κB pathway seems indispensable in the proinflammatory effect of SP on synoviocytes. This original discovery may indicate a potential clinical drug target and the development of innovative therapies for DDH.