Search Results (785)

Blood–testis barrier (BTB) genes are crucial for the cellular mechanisms of spermatogenesis as they protect against detrimental cytotoxic agents, chemicals, and pathogens, thereby maintaining a sterile environment necessary for sperm development. BTB proteins predominantly consist of extensive tight and gap junctions formed between Sertoli cells. These junctions form a crucial immunological barrier restricting the intercellular movement of substances and molecules within the adluminal compartment. Epithelial tight junctions are complex membrane structures composed of various integral membrane proteins, including claudins, zonula occludens-1, and occludin. Inter-testicular cell junction proteins undergo a constant process of degradation and renewal. In addition, the downregulation of genes crucial to the development and preservation of cell junctions could disrupt the functionality of the BTB, potentially leading to male infertility. Oxidative stress and inflammation may contribute to disrupted spermatogenesis, resulting in male infertility. L-cysteine is a precursor to glutathione, a crucial antioxidant that helps mitigate damage and inflammation resulting from oxidative stress. Preclinical research indicates that L-cysteine may offer protective benefits against testicular injury and promote the expression of BTB genes. This review emphasizes various BTB genes essential for preserving its structural integrity and facilitating spermatogenesis and male fertility. Furthermore, it consolidates various research findings suggesting that L-cysteine may promote the expression of BTB-associated genes, thereby aiding in the maintenance of testicular functions. Full article

Itaconic acid (IA) is recognized for its potential application in treating intestinal diseases owing to the anti-inflammatory and antioxidant properties. Perfluorooctanoic acid (PFOA) can accumulate in animals and result in oxidative and inflammatory damages to multi-tissue and organ, particularly in the intestinal tract. This study aimed to explore whether IA could mitigate intestinal damage induced by PFOA exposure in laying hens and elucidate its potential underlying mechanisms. The results showed that IA improved the antioxidant capacity of laying hens and alleviated the oxidative damage induced by PFOA, as evidenced by the elevated activities of T-SOD, GSH-Px, and CAT, and the decreased MDA content in both the jejunum and serum. Furthermore, IA improved the intestinal morphological and structural integrity, notably attenuating PFOA-induced villus shedding, length reduction, and microvillus thinning. IA also upregulated the mRNA expression of ZO-1, Occludin, Claudin-1, and Mucin-2 in the jejunum, thereby restoring intestinal barrier function. Compared with the PF group, IA supplementation downregulated the gene expression of Keap1 and upregulated the HO-1, NQO1, SOD1, and GPX1 expression in the jejunum. Meanwhile, the PF + IA group exhibited lower expressions of inflammation-related genes (NF-κB, IL-1β, IFN-γ, TNF-α, and IL-6) compared to the PF group. Moreover, IA reversed the PFOA-induced imbalance in gut microbiota by reducing the harmful bacteria such as Escherichia-Shigella, Clostridium innocuum, and Ruminococcus torques, while increasing the abundance of beneficial bacteria like Lactobacillus. Correlation analysis further revealed a significant association between gut microbes, inflammatory factors, and the Keap1/Nrf2/HO-1 pathway expression. In conclusion, dietary IA supplementation could alleviate the oxidative and inflammatory damage caused by PFOA exposure in the intestinal tract by reshaping the intestinal microbiota, modulating the Keap1/Nrf2/HO-1 pathway and reducing oxidative stress and inflammatory response, thereby promoting intestinal homeostasis. Full article

Diabetic retinopathy (DR) is a leading cause of blindness, yet its molecular mechanisms are unclear. Extracellular vesicles (EVs) contribute to dysfunction in DR, but the characteristics and functions of vitreous EVs are unclear. This study investigated the inflammatory properties of type 2 diabetic (db) vitreous EVs. EVs isolated from the vitreous of db and non-db donors were used for nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), immunogold staining, Western blotting, and proteomic analysis by mass spectrometry. Intracellular uptake of vitreous EVs by differentiated macrophages was evaluated using ExoGlow membrane labeling, and the impact of EVs on macrophage (THP-1) activation was assessed by cytokine levels using RT-qPCR. NTA and TEM analysis of db and non-db vitreous EVs showed non-aggregated EVs with a heterogeneous size range below 200 nm. Western blot detected EV markers (Alix, Annexin V, HSP70, and Flotillin 1) and an upregulation of Cldn5 in db EVs. While the db EVs were incorporated into macrophages, treatment of THP-1 cells with db EVs significantly increased mRNA levels of TNFα and IL-1β compared to non-db EVs. Proteomic and gene enrichment analysis indicated pro-inflammatory characteristics of db EVs. Our results suggest a potential involvement of EC-derived Cldn5+ EVs in triggering inflammation, offering a novel mechanism involved and presenting a possible therapeutic avenue for DR. Full article

To investigate the possible protective effect of hesperidin on intestinal damage caused by high-temperature heat stress in yellow-feathered broilers, 960 broilers aged 21 days were randomly divided into four groups: HT, HT300, HT450, and HT600, with each group receiving different amounts of hesperidin supplementation (0, 300, 450, and 600 mg/kg). The dietary supplementation of hesperidin could mitigate the elevation of corticosterone (CORT) and adrenocorticotropic hormone (ATCH) levels in serum from yellow-feathered broilers induced by heat stress. The supplementation of 300 mg/kg and 450 mg/kg of hesperidin reduced crypt depth and increased the V/C ratio in the small intestine compared to the HT group. The dietary supplementation of hesperidin decreased endotoxin and D-lactic acid levels in the blood, and dietary supplementation of 300 mg/kg of hesperidin increased the expression of claudin-1 and ZO-1 mRNA in the jejunum compared with the HT group. Furthermore, the dietary supplementation of 300 mg/kg of hesperidin decreased serum IL-1β and IL-6 levels. In comparison, supplementation with 300 mg/kg and 450 mg/kg of hesperidin decreased serum TNF-α levels in yellow-feathered broilers compared to the HT group. Moreover, the dietary supplementation of hesperidin decreased NF-κB mRNA levels. Overall, these data suggest that dietary supplementation with hesperidin potentially improves intestinal injury caused by heat stress in yellow-feathered broilers. Full article

Background: The pathogenesis of inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease is not well understood. This study investigated the roles and regulation of the claudin-1, -2, -3, and -4 isoforms in the pathogenesis of ulcerative colitis, and the potential therapeutic effects of nobiletin. Methods: Colitis was induced in rats by administering dextran sulfate sodium [DSS] in drinking water for seven days. Animals were treated daily with nobiletin [oral, 60 mg/Kg body weight] and studied in four groups, C [non-colitis control], D [DSS-induced colitis], CN [nobiletin-treated non-colitis control], and DN [nobiletin-treated DSS-induced colitis]. On day seven, the animals were sacrificed, and colonic tissues were collected and analyzed. Results: Both macroscopic and microscopic findings suggest the progression of colitis. In the inflamed colon, claudin-1 and -4 proteins were decreased, claudin-2 increased, while the claudin-3 protein remained unchanged. Except for claudin-1, these changes were not paralleled by mRNA expression, indicating a complex regulatory mechanism. Uniform β-actin expression along with consistent quality and yield of total RNA indicated selectivity of these changes. Nobiletin treatment reversed these changes. Conclusions: Altered expression of the claudin isoforms -1, -2, and -4 disrupts tight junctions, exposing the lamina propria to microflora, leading to electrolyte disturbance and the development of ulcerative colitis. Nobiletin with its anti-inflammatory properties may be useful in IBD. Full article

Dietary energy is crucial for ruminants’ performance and health. To determine optimal dietary energy levels for growing sheep, we evaluated their growth performance, nutrient digestibility, rumen fermentation, barrier function, and microbiota under varying metabolic energy (ME) diets. Forty-five growing Yunnan semi-fine wool sheep, aged 10 months and weighing 30.8 ± 1.9 kg, were randomly allocated to five treatments, each receiving diets with ME levels of 8.0, 8.6, 9.2, 9.8 or 10.4 MJ/kg. The results showed that with increasing dietary energy, the average daily gain (ADG) as well as the digestibility of dry matter (DM) and organic matter (OM) increased (p < 0.05), while the feed conversion ratio (FCR) decreased linearly (p = 0.01). The concentration of total VFA (p = 0.03) and propionate (p = 0.01) in the rumen increased linearly, while rumen pH (p < 0.01) and the acetate–propionate ratio (p = 0.01) decreased linearly. Meanwhile, the protein contents of Claudin-4, Claudin-7, Occludin and ZO-1 as well as the relative mRNA expression of Claudin-4 and Occludin also increased (p < 0.05). In addition, rumen bacterial diversity decreased with the increase of dietary energy, and the relative abundance of some bacteria (like Saccharofermentans, Prevotella and Succiniclasticum) changed. In conclusion, increasing dietary energy levels enhanced growth performance, nutrient digestibility, rumen fermentation, and barrier function, and altered the rumen bacterial community distribution. The optimal dietary ME for these parameters in sheep at this growth stage was between 9.8 and 10.4 MJ/kg. Full article

This study aimed to investigate the effects of ursolic acid (UA) on the growth performance and intestinal health of largemouth bass (Micropterus salmoides). Four diets were formulated with UA supplementation at 0, 250, 500, and 1000 mg/kg, defined as the control (CON), UA250, UA500, and UA1000, respectively. After an 8-week feeding experiment, the results showed that, in the UA500 group, the final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) increased, and the feed conversion ratio (FCR) and hepatosomatic index decreased. Total superoxide dismutase (T-SOD) activity exhibited a significant increase, and malondialdehyde (MDA) content decreased. An intestinal histological analysis revealed an improvement in the intestinal structural integrity of the UA500 group. The mRNA relative expression levels of physical barrier-related genes [occludin, claudin-1, and zonula occluden-1 (zo-1)] were upregulated. The mRNA relative expression of interlenkin 10 (il-10) increased, and the mRNA relative expression of interlenkin 1β (il-1β) and tumor necrosis factor-α (tnf-α) significantly decreased. The abundance of Firmicutes and Proteobacteria decreased, and the abundance of Tenericutes increased. The abundance of Mycoplasma, Cyanobium, and Staphylococcus decreased, while the abundance of Clostridium increased. In conclusion, dietary supplementation of UA significantly enhanced the growth performance and antioxidant capacity of largemouth bass while improving intestinal barrier function through its influence on the abundance of intestinal flora, such as Tenericutes, Firmicutes, and Mycoplasma. Optimal dietary UA levels for largemouth bass were determined to be between 498 and 520 mg/kg based on quadratic regression analyses of WGR, SGR, and FCR or T-SOD and MDA content. Full article

All subtypes of Clostridium perfringens (C. perfringens) produce the alpha toxin (CPA), which can cause enteritis or enterotoxemia in lambs, cattle, pigs, and horses, as well as traumatic clostridial myonecrosis in humans and animals. CPA acts on cell membranes, ultimately leading to endocytosis and cell death. Therefore, the neutralization of CPA is crucial for the prevention and treatment of diseases caused by C. perfringens. In this study, utilizing CPA as an antigen, a nanobody (CPA-VHH) with a half-life of 2.9 h, an affinity constant (KD) of 0.9 nmol/L, and good stability below 60 °C was prepared from a natural nanobody library from alpacas. The biological activity analysis of CPA-VHH revealed its ability to effectively neutralize the phospholipase and hemolytic activity of CPA at a 15-fold ratio. In Vero cells, 9.8 μg/mL CPA-VHH neutralized the cytotoxicity of CPA at two times the half-maximal inhibitory concentration (IC₅₀). In a mouse model, 35.7 ng/g body weight (BW) of CPA-VHH neutralized 90% of the lethality caused by a 2× median lethal dose (LD₅₀) of CPA. It was found that CPA-VHH protected 80% of mice within 30 min at 2 × LD₅₀ CPA, but this dropped below 50% after 2 h and to 0% after 4 h. Rescue trials indicated that using CPA-VHH within 30 min post-infection with 2 × LD₅₀ CPA achieved an 80% rescue rate, which decreased to 10% after 2 h. Furthermore, CPA-VHH effectively mitigated the reduction in the expression levels of zonula occludens-1 (ZO-1), Occludin, and Claudin-1, while also attenuating the upregulation of the pro-inflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-7 (IL-7), interleukin-8 (IL-8), tumor necrosis factor α (TNF-α), and interferon-γ (IFN-γ) induced by CPA infection. Overall, this study has identified a specific nanobody, CPA-VHH, that effectively neutralizes CPA toxins in vitro and in animal models, providing a new tool for inhibiting the pathogenicity resulting from these toxins and laying an important foundation for the development of new anti-C. perfringens toxin-related therapeutic products. Full article

Invasive lobular carcinoma exhibits unique morphological features frequently associated with alterations in CDH1. Although some studies have identified abnormalities in adhesion factors other than E-cadherin, the molecular mechanisms underlying E-cadherin abnormalities in CDH1-unaltered invasive lobular carcinoma remain poorly understood. In this study, we investigated the molecular underpinnings of E-cadherin dysregulation in invasive lobular carcinoma in the absence of CDH1 gene alterations, using comprehensive bioinformatic analyses. We conducted a comparative study of CDH1-mutated and non-mutated invasive lobular carcinoma and evaluated the differences in mRNA levels, reverse-phase protein array, methylation, and miRNAs. We observed that invasive lobular carcinoma cases without CDH1 alterations exhibited a significantly higher incidence of the Claudin-low subtype (p < 0.01). The results of the reverse-phase protein array indicate no significant difference in E-cadherin expression between CDH1-mutated and non-mutated cases. Therefore, abnormalities in E-cadherin production also exist in CDH1 non-mutated invasive lobular carcinoma. Considering that there are no differences in mRNA levels and methylation status, post-translational modifications are the most plausible explanation for the same. Hence, future studies should focus on elucidating the mechanism underlying E-cadherin inactivation via post-translational modifications in CDH1 non-mutated invasive lobular carcinoma. Full article

Crohn’s disease (CD) is a type of inflammatory bowel disease (IBD) affecting the gastrointestinal tract that can also cause extra-intestinal complications. Following exposure to the mRNA vaccine BNT162b2 (Pfizer-BioNTech) encoding the SARS-CoV-2 Spike (S) protein, some patients experienced a lack of response to the biological drug Adalimumab and a recrudescence of the disease. In CD patients in progression, resistant to considered biological therapy, an abnormal increase in intestinal permeability was observed, more often with a modulated expression of different proteins such as Aquaporin 8 (AQP8) and in tight junctions (e.g., ZO-1, Claudin1, Claudin2, Occludin), especially during disease flares. The aim of this study is to investigate how the SARS-CoV-2 vaccine could interfere with IBD therapy and contribute to disease exacerbation. We investigated the role of the SARS-CoV-2 Spike protein, transported by extracellular vesicles (EVs), and the impact of various EVs components, namely, exosomes (EXOs) and microvesicles (MVs), in modulating the expression of molecules involved in the exacerbation of CD, which remains unknown. Full article

Laminins are essential components of the basement membranes, expressed in a tissue- and cell-specific manner under physiological conditions. During inflammatory circumstances, such as atherosclerosis, alterations in laminin composition within vessels have been observed. Our study aimed to assess the influence of tumor necrosis factor-alpha (TNF), a proinflammatory cytokine abundantly found in atherosclerotic lesions, on endothelial laminin gene expression and the effects of laminin-332 (LN332) on endothelial cells’ behavior. We also evaluated the expression of LN332-encoding genes in human carotid atherosclerotic plaques. Our findings demonstrate that TNF induces upregulation of LAMB3 and LAMC2, which, along with LAMA3, encode the LN332 isoform. Endothelial cells cultured on recombinant LN332 exhibit decreased claudin-5 expression and display a loosely connected phenotype, with an elevated expression of chemokines and leukocyte adhesion molecules, enhancing their attractiveness and adhesion to leukocytes in vitro. Furthermore, LAMB3 and LAMC2 are upregulated in human carotid plaques and show a positive correlation with TNF expression. In summary, TNF stimulates the expression of LN332-encoding genes in human endothelial cells and LN332 promotes an endothelial phenotype characterized by compromised junctional integrity and increased leukocyte interaction. These findings highlight the importance of basement membrane proteins for endothelial integrity and the potential role of LN332 in atherosclerosis. Full article

Obesity is an established risk and progression factor for triple-negative breast cancer (TNBC), but preclinical studies to delineate the mechanisms underlying the obesity-TNBC link as well as strategies to break that link are constrained by the lack of tumor models syngeneic to obesity-prone mouse strains. C3(1)/SV40 T-antigen (C3-TAg) transgenic mice on an FVB genetic background develop tumors with molecular and pathologic features that closely resemble human TNBC, but FVB mice are resistant to diet-induced obesity (DIO). Herein, we sought to develop transplantable C3-TAg cell lines syngeneic to C57BL/6 mice, an inbred mouse strain that is sensitive to DIO. We backcrossed FVB-Tg(C3-1-TAg)cJeg/JegJ to C57BL/6 mice for ten generations, and spontaneous tumors from those mice were excised and used to generate four clonal cell lines (B6TAg1.02, B6TAg2.03, B6TAg2.10, and B6TAg2.51). We characterized the growth of the four cell lines in both lean and DIO C57BL/6J female mice and performed transcriptomic profiling. Each cell line was readily tumorigenic and had transcriptional profiles that clustered as claudin-low, yet markedly differed from each other in their rate of tumor progression and transcriptomic signatures for key metabolic, immune, and oncogenic signaling pathways. DIO accelerated tumor growth of orthotopically transplanted B6TAg1.02, B6TAg2.03, and B6TAg2.51 cells. Thus, the B6TAg cell lines described herein offer promising and diverse new models to augment the study of DIO-associated TNBC. Full article

Recent studies point to intestinal permeability as an important factor in the establishment and development of rheumatoid arthritis (RA). Tight junctions (TJs) play a major role in intestinal homeostasis. The alteration of this homeostasis is related to RA. Furthermore, RA patients present dysbiosis and a lower microbiota diversity compared to healthy individuals. A cross-sectional study including RA patients and sex- and age-matched healthy controls was performed. The quantification of TJ proteins was carried out by ELISA. Gut microbiota was evaluated by NGS platform Ion Torrent S. The inflammatory variables included were DAS28, CRP, inflammatory cytokines (IL-6, IL-1, TNF-α) and oxidised LDL. Claudin-1 levels showed significant differences between groups. Results evidenced a correlation between claudin-1 values and age (r: −0.293; p < 0.05), IL6 (r: −0.290; p < 0.05) and CRP (r: −0.327; p < 0.05), and between zonulin values and both age (r: 0.267; p < 0.05) and TNFα (r: 0.266; p < 0.05). Moreover, claudin-1 and CRP levels are related in RA patients (β: −0.619; p: 0.045), and in patients with high inflammatory activity, the abundance of the genus Veillonella is positively associated with claudin-1 levels (β: 39.000; p: 0.004). Full article

The use of cinnamaldehyde and Vitamin C can improve immunity and intestinal health. A two-way factorial design was employed to investigate the main and interactive effects of cinnamaldehyde and vitamin C on the growth, carcass, and intestinal health of broiler chickens. A total of 288 one-day-old female Arbor Acres broiler chicks were randomly distributed among four treatment groups, consisting of six replicate cages with 12 birds each. Four treatments were basal diet or control (CON), supplemental cinnamaldehyde (CA) 300 g/ton (g/t), vitamin C (VC) 300 g/t, and cinnamaldehyde 300 g/t, and vitamin C 300 g/t (CA + VC), respectively. The results showed that supplemental CA did not affect the growth performance or slaughter performance of broilers at 21 days (d), 42 days (d), and 1–42 days (d); however, it could improve intestinal barrier function at 42 d of age and reduce the mRNA expression of inflammatory factors in the intestine at 21 d and 42 d of age. Supplemental VC showed a trend towards increasing body weight gain (BWG) at 21 d (p = 0.094), increased breast muscle rate (at 21-d 5.33%, p < 0.05 and at 42-d 7.09%, p = 0.097), and decreased the abdominal fat (23.43%, p < 0.05) and drip loss (20.68%, p < 0.05) at 42-d. Moreover, VC improves intestinal morphology and intestinal barrier function and maintains a balanced immune response. The blend of CA and VC significantly upregulated the mRNA expression of myeloid differentiation factor 88 (MyD-88) in the intestine at 21 d of age, the mRNA expression of catalase (CAT), Occludin, Claudin-1, Mucin-2, nuclear factor-kappa B (NF-κB) and toll-like receptor 4 (TLR-4) in the intestine at 42 d of age (p < 0.01), and downregulated the mRNA expression of interleukin 10 (IL-10), interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α) in the intestine at 21-d and 42-d of age, and interleukin-1 beta (IL-1β) mRNA in intestine at 42 d of age (p < 0.01). This study suggested that the combination of CA and VC had the potential to regulate intestinal health and result in better carcass character of broilers. Full article

Background: Lipid metabolism disorder appears to be one of the early features of alcoholic liver disease (ALD), which can be speculated via omics analysis including liver transcriptomics and gut microbiota. A complex consisting of the roots of Pueraria lobata and dried fruits of Prunus mume (PPC), which possesses hepatoprotective effects, could serve as a drug or functional food. The lack of non-polysaccharide compounds in PPC with their moderation effects on gut microbiota suggests the necessity for a relevant study. Methods: Six groups of Kunming mice (control, Baijiu injury, silybin, low, medium, and high) were modelled by gavage with Baijiu (for 14 days) and PPC (equivalent to a maximum dose of 9 g/kg in humans). The liver transcriptome data were analyzed to predict gene annotation, followed by the verification of gut microbiota, serum, tissue staining, immunohistochemistry, and Western blotting. Liquid chromatography-mass spectrometry was used to detect the components. Results: PPC normalized serum ALT (40 U/L), down-regulated TLR4-NF-κB signaling pathway to inhibit the release of TNF-α (90 pg/mL), improved the expression of occludin, claudin-4, and ZO-1, and restored the abundance of Muribaculaceae, Bacteroides and Streptococcus. Conclusion: PPC can alleviate ALD by regulating the gut microbiota with an anti-inflammatory and intestinal barrier, and has an application value in developing functional foods. Full article