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The precise neurophysiological changes prompted by meningeal lymphatic dysfunction remain unclear. Here, we showed that inducing meningeal lymphatic vessel ablation in adult mice led to gene expression changes in glial cells, followed by reductions in mature oligodendrocyte numbers and specific lipid species in the brain. These phenomena were accompanied by altered meningeal adaptive immunity and brain myeloid cell activation. During brain remyelination, meningeal lymphatic dysfunction provoked a state of immunosuppression that contributed to delayed spontaneous oligodendrocyte replenishment and axonal loss. The deficiencies in mature oligodendrocytes and neuroinflammation due to impaired meningeal lymphatic function were solely recapitulated in immunocompetent mice. Patients diagnosed with multiple sclerosis presented reduced vascular endothelial growth factor C in the cerebrospinal fluid, particularly shortly after clinical relapses, possibly indicative of poor meningeal lymphatic function. These data demonstrate that meningeal lymphatics regulate oligodendrocyte function and brain myelination, which might have implications for human demyelinating diseases.
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Encéfalo , Vasos Linfáticos , Meninges , Esclerose Múltipla , Bainha de Mielina , Oligodendroglia , Animais , Oligodendroglia/metabolismo , Camundongos , Meninges/imunologia , Encéfalo/metabolismo , Encéfalo/imunologia , Humanos , Bainha de Mielina/metabolismo , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Camundongos Endogâmicos C57BL , Sobrevivência Celular , Remielinização , Feminino , Masculino , Imunidade AdaptativaRESUMO
Concomitant with DNA replication, the chromosomal cohesin complex establishes cohesion between newly replicated sister chromatids. Several replication-fork-associated "cohesion establishment factors," including the multifunctional Ctf18-RFC complex, aid this process in as yet unknown ways. Here, we show that Ctf18-RFC's role in sister chromatid cohesion correlates with PCNA loading but is separable from its role in the replication checkpoint. Ctf18-RFC loads PCNA with a slight preference for the leading strand, which is dispensable for DNA replication. Conversely, the canonical Rfc1-RFC complex preferentially loads PCNA onto the lagging strand, which is crucial for DNA replication but dispensable for sister chromatid cohesion. The downstream effector of Ctf18-RFC is cohesin acetylation, which we place toward a late step during replication maturation. Our results suggest that Ctf18-RFC enriches and balances PCNA levels at the replication fork, beyond the needs of DNA replication, to promote establishment of sister chromatid cohesion and possibly other post-replicative processes.
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Proteínas de Ciclo Celular/metabolismo , Cromátides/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Cromossomos Fúngicos/fisiologia , Replicação do DNA , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Acetiltransferases/genética , Acetiltransferases/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Segregação de Cromossomos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Proteína de Replicação C/genética , Proteína de Replicação C/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , CoesinasRESUMO
The precise regulation of DNA replication is vital for cellular division and genomic integrity. Central to this process is the replication factor C (RFC) complex, encompassing five subunits, which loads proliferating cell nuclear antigen onto DNA to facilitate the recruitment of replication and repair proteins and enhance DNA polymerase processivity. While RFC1's role in cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) is known, the contributions of RFC2-5 subunits on human Mendelian disorders is largely unexplored. Our research links bi-allelic variants in RFC4, encoding a core RFC complex subunit, to an undiagnosed disorder characterized by incoordination and muscle weakness, hearing impairment, and decreased body weight. We discovered across nine affected individuals rare, conserved, predicted pathogenic variants in RFC4, all likely to disrupt the C-terminal domain indispensable for RFC complex formation. Analysis of a previously determined cryo-EM structure of RFC bound to proliferating cell nuclear antigen suggested that the variants disrupt interactions within RFC4 and/or destabilize the RFC complex. Cellular studies using RFC4-deficient HeLa cells and primary fibroblasts demonstrated decreased RFC4 protein, compromised stability of the other RFC complex subunits, and perturbed RFC complex formation. Additionally, functional studies of the RFC4 variants affirmed diminished RFC complex formation, and cell cycle studies suggested perturbation of DNA replication and cell cycle progression. Our integrated approach of combining in silico, structural, cellular, and functional analyses establishes compelling evidence that bi-allelic loss-of-function RFC4 variants contribute to the pathogenesis of this multisystemic disorder. These insights broaden our understanding of the RFC complex and its role in human health and disease.
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Proteína de Replicação C , Humanos , Proteína de Replicação C/genética , Proteína de Replicação C/metabolismo , Masculino , Células HeLa , Feminino , Fenótipo , Replicação do DNA/genética , Adulto , Mutação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , AlelosRESUMO
BACKGROUND: Single-domain von Willebrand factor type C (SVWC) constitute a protein family predominantly identified in arthropods, characterized by a SVWC domain and involved in diverse physiological processes such as host defense, stress resistance, and nutrient metabolism. Nevertheless, the physiological mechanisms underlying these functions remain inadequately comprehended. RESULTS: A massive expansion of the SVWC gene family in Musca domestica (MdSVWC) was discovered, with a count of 35. MdSVWC1 was selected as the representative of the SVWC family for functional analysis, which led to the identification of the immune function of MdSVWC1 as a novel pattern recognition receptor. MdSVWC1 is highly expressed in both the fat body and intestines and displays acute induction upon bacterial infection. Recombinant MdSVWC1 binds to surfaces of both bacteria and yeast through the recognition of multiple pathogen-associated molecular patterns and exhibits Ca2+-dependent agglutination activity. MdSVWC1 mutant flies exhibited elevated mortality and hindered bacterial elimination following bacterial infection as a result of reduced hemocyte phagocytic capability and weakened expression of antimicrobial peptide (AMP) genes. In contrast, administration of recombinant MdSVWC1 provided protection to flies from bacterial challenges by promoting phagocytosis and AMP genes expression, thereby preventing bacterial colonization. MdSPN16, a serine protease inhibitor, was identified as a target protein of MdSVWC1. It was postulated that the interaction of MdSVWC1 with MdSPN16 would result in the activation of an extracellular proteolytic cascade, which would then initiate the Toll signaling pathway and facilitate the expression of AMP genes. CONCLUSIONS: MdSVWC1 displays activity as a soluble pattern recognition receptor that regulates cellular and humoral immunity by recognizing microbial components and facilitating host defense.
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Moscas Domésticas , Proteínas de Insetos , Receptores de Reconhecimento de Padrão , Animais , Moscas Domésticas/genética , Moscas Domésticas/microbiologia , Moscas Domésticas/imunologia , Receptores de Reconhecimento de Padrão/metabolismo , Receptores de Reconhecimento de Padrão/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Fagocitose , Imunidade Inata , Peptídeos Antimicrobianos/genética , Peptídeos Antimicrobianos/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: Deficiencies of protein C (PC) or protein S (PS) are rare diseases, characterized by mutations in the PC or PS genes, which encode plasma serine proteases with anti-coagulant activity. Severe PC or PS deficiencies manifest in early life as neonatal purpura fulminans, a life-threatening heamorrhagic condition requiring immediate treatment. First-line treatment involves replacement therapy, followed by maintenance with anti-coagulants. Replacement therapy with specific protein concentrates is currently only limited to PC, and therefore, a PC + PS concentrate represents a useful addition to therapeutic options, particularly for severe PS deficiency. Further, the production of a PC + PS concentrate from unused plasma fractionation intermediates would impact favourably on manufacturing costs, and consequently therapy prices for patients and health systems. MATERIALS AND METHODS: Several chromatographic runs were performed on the same unused plasma fractionation intermediates using different supports to obtain a PC/PS concentrate. The best chromatographic mediums were chosen, in terms of specific activity and recovery. A full process of purification including virus inactivation/removal and lyophilization steps was set up. RESULTS: The final freeze-dried product had a mean PC concentration of 47.75 IU/mL with 11% of PS, and a mean specific activity of 202.5 IU/mg protein, corresponding to over 12,000-fold purification from plasma. CONCLUSION: The development of a novel concentrated PC/PS mixture obtained from a waste fraction of other commercial products could be used for its potential therapeutic role in the management of neonatal purpura fulminans pathology.
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Deficiência de Proteína C , Púrpura Fulminante , Recém-Nascido , Humanos , Púrpura Fulminante/tratamento farmacológico , Púrpura Fulminante/genética , Deficiência de Proteína C/tratamento farmacológico , Proteína C/análise , Proteína C/uso terapêutico , Proteína S , Plasma/químicaRESUMO
Secondary lymphedema is caused by damage to the lymphatic system from surgery, cancer treatment, infection, trauma, or obesity. This damage induces stresses such as oxidative stress and hypoxia in lymphatic tissue, impairing the lymphatic system. In response to damage, vascular endothelial growth factor C (VEGF-C) levels increase to induce lymphangiogenesis. Unfortunately, VEGF-C often fails to repair the lymphatic damage in lymphedema. The underlying mechanism contributing to lymphedema is not well understood. In this study, we found that surgery-induced tail lymphedema in a mouse model increased oxidative damage and cell death over 16 days. This corresponded with increased VEGF-C levels in mouse tail lymphedema tissue associated with macrophage infiltration. Similarly, in the plasma of patients with secondary lymphedema, we found a positive correlation between VEGF-C levels and redox imbalance. To determine the effect of oxidative stress in the presence or absence of VEGF-C, we found that hydrogen peroxide (H2O2) induced cell death in human dermal lymphatic endothelial cells (HDLECs), which was potentiated by VEGF-C. The cell death induced by VEGF-C and H2O2 in HDLECs was accompanied by increased reactive oxygen species (ROS) levels and a loss of mitochondrial membrane potential. Antioxidant pre-treatment rescued HDLECs from VEGF-C-induced cell death and decreased ROS under oxidative stress. As expected, VEGF-C increased the number of viable and proliferating HDLECs. However, upon H2O2 treatment, VEGF-C failed to increase either viable or proliferating cells. Since oxidative stress leads to DNA damage, we also determined whether VEGF-C treatment induces DNA damage in HDLECs undergoing oxidative stress. Indeed, DNA damage, detected in the form of gamma H2AX (γH2AX), was increased by VEGF-C under oxidative stress. The potentiation of oxidative stress damage induced by VEFG-C in HDLECs was associated with p53 activation. Finally, the inhibition of vascular endothelial growth factor receptor-3 (VEGFR-3) activation blocked VEGF-C-induced cell death following H2O2 treatment. These results indicate that VEGF-C further sensitizes lymphatic endothelial cells to oxidative stress by increasing ROS and DNA damage, potentially compromising lymphangiogenesis.
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Apoptose , Dano ao DNA , Células Endoteliais , Peróxido de Hidrogênio , Linfedema , Mitocôndrias , Estresse Oxidativo , Fator C de Crescimento do Endotélio Vascular , Fator C de Crescimento do Endotélio Vascular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Linfedema/metabolismo , Linfedema/patologia , Linfedema/etiologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos , Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Linfangiogênese/efeitos dos fármacos , FemininoRESUMO
Malignant breast cancers pose a notable challenge when it comes to treatment options. Recently, research has implicated extracellular vesicles (EVs) secreted by cancer cells in the formation of a pre-metastatic niche. Small clumps of CD44-positive breast cancer cells are efficiently transferred through CD44-CD44 protein homophilic interaction. This study aims to examine the function of CD44-positive EVs in pre-metastatic niche formation in vitro and to suggest a more efficacious EV formulation. We used mouse mammary carcinoma cells, BJMC3879 Luc2 (Luc2 cells) as the source of CD44-positive EVs and mouse endothelial cells (UV2 cells) as the recipient cells in the niche. Luc2 cells exhibited an enhanced secretion of EVs expressing CD44 and endothelial growth factors (VEGF-A, -C) under 20% O2 (representative of the early stage of tumorigenesis) compared to its expression under 1% O2 (in solid tumor), indicating that pre-metastatic niche formation occurs in the early stage. Furthermore, UV2 endothelial cells expressing CD44 demonstrated a high level of engulfment of EVs that had been supplemented with hyaluronan, and the proliferation of UV2 cells occurred following the engulfment of EVs. These results suggest that anti-VEGF-A and -C encapsulated, CD44-expressing, and hyaluronan-coated EVs are more effective for tumor metastasis.
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Vesículas Extracelulares , Receptores de Hialuronatos , Animais , Receptores de Hialuronatos/metabolismo , Vesículas Extracelulares/metabolismo , Camundongos , Feminino , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Metástase Neoplásica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proliferação de Células , Microambiente Tumoral , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Ácido Hialurônico/metabolismoRESUMO
Interleukin-1 receptor antagonist (IL-1RA) has been shown to play an important role in cancer progression. However, its pathogenic effects and molecular mechanism in the malignant progression of esophageal squamous cell carcinoma (ESCC) remain largely unknown. This study was designed to explore the function of IL-1RA in ESCC and determine the relationship between IL-1RA and lymph node metastasis in ESCC patients. The clinical relevance of IL-1RA in relation to the clinicopathological features and prognosis of 100 ESCC patients was analyzed. The function and underlying mechanisms of IL-1RA in the growth, invasion, and lymphatic metastasis in ESCC were explored both in vitro and in vivo. The therapeutic effect of anakinra, an IL-1 receptor antagonist, on ESCC was also evaluated in animal experiments. Downregulation of IL-1RA was observed in ESCC tissues and cells and was found to be strongly correlated with pathological stage (P = 0.034) and lymphatic metastasis (P = 0.038). Functional assays demonstrated that upregulation of IL-1RA reduced cell proliferation, migration, and lymphangiogenesis both in vitro and in vivo. Mechanistic studies revealed that overexpression of IL-1RA activated the epithelial-to-mesenchymal transition (EMT) in the ESCC cells through activation of MMP9 and regulation of the expression and secretion of VEGF-C through the PI3K/NF-κB pathway. Anakinra treatment resulted in significant inhibition of tumor growth, lymphangiogenesis, and metastasis. IL-1RA inhibits lymph node metastasis of ESCC by regulating the EMT through activation of matrix metalloproteinase 9(MMP9) and lymphangiogenesis, driven by VEGF-C and the NF-κB signaling pathway. Anakinra may be an effective drug for the inhibition of ESCC tumor formation and lymph node metastasis.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Linfangiogênese/genética , Metástase Linfática , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/genética , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismoRESUMO
The lymphatic vascular system is crucial for the regulation of tissue fluid homeostasis, lipid metabolism, and immune function. Cardiac injury quickly leads to myocardial edema, cardiac lymphatic dysfunction, which ultimately results in myocardial fluid imbalance and cardiac dysfunction. Therefore, lymphangiogenesis-targeted therapy may improve the recovery of myocardial function post cardiac ischemia as observed in myocardial infarction (MI). Indeed, a promising strategy for the clinical treatment of MI relies on vascular endothelial growth factor-C (VEGF-C)-targeted therapy, which promotes lymphangiogenesis. However, much effort is needed to identify the mechanisms of lymphatic transport in response to heart disease. This article reviews regulatory factors of lymphangiogenesis, and discusses the effects of lymphangiogenesis on cardiac function after cardiac injury and its regulatory mechanisms. The involvement of stem cells on lymphangiogenesis was also discussed as stem cells could differentiate into lymphatic endothelial cells (LECs) and stimulate phenotype of LECs.
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Vasos Linfáticos , Infarto do Miocárdio , Isquemia Miocárdica , Humanos , Células Endoteliais/metabolismo , Linfangiogênese , Vasos Linfáticos/metabolismo , Infarto do Miocárdio/metabolismo , Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: To reveal the overall sperm retrieval rate (SRR) and range in patients with azoospermia factor c (AZFc) microdeletion azoospermia by microdissection testicular sperm extraction (mTESE) and discuss the differences of preoperative patient factors among studies with various SRRs. PATIENTS AND METHODS: We searched PubMed, Web of Science and Embase until February 2023. All studies reporting SRRs by mTESE and required parameters of patients with AZFc microdeletions were included. The primary outcome was the SRR and, if available, the pregnancy rate (PR) and live-birth rate (LBR) after intracytoplasmic sperm injection were also investigated as secondary outcomes. RESULTS: Eventually 11 cohort studies were included in this review. A total number of 441 patients underwent mTESE and in 275 of them sperm was obtained, reaching an overall SRR of 62.4%. The SRRs among studies had a wide range from 25.0% to 85.7%. The studies reporting higher SRRs generally had older mean ages, and higher follicle-stimulating hormone and testosterone levels. Only four studies provided practical data on pregnancies and live-born children of patients with AZFc microdeletions, so the overall PR and LBR were unavailable. CONCLUSIONS: The overall SRR of patients with AZFc microdeletion azoospermia was 62.4%. The effect of patient factors in SR needs further evidence in future work.
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BACKGROUND AND PURPOSE: Biallelic mutation/expansion of the gene RFC1 has been described in association with a spectrum of manifestations ranging from isolated sensory neuro(no)pathy to a complex presentation as cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS). Our aim was to define the frequency and characteristics of small fiber neuropathy (SFN) in RFC1 disease at different stages. METHODS: RFC1 cases were screened for SFN using the Neuropathic Pain Symptom Inventory and Composite Autonomic Symptom Score 31 questionnaires. Clinical data were retrospectively collected. If available, lower limb skin biopsy samples were evaluated for somatic epidermal and autonomic subepidermal structure innervation and compared to healthy controls (HCs). RESULTS: Forty patients, median age at onset 54 years (interquartile range [IQR] 49-61) and disease duration 10 years (IQR 6-16), were enrolled. Mild-to-moderate positive symptoms (median Neuropathic Pain Symptom Inventory score 12.1/50, IQR 5.5-22.3) and relevant autonomic disturbances (median Composite Autonomic Symptom Score 31 37.0/100, IQR 17.7-44.3) were frequently reported and showed scarce correlation with disease duration. A non-length-dependent impairment in nociception was evident in both clinical and paraclinical investigations. An extreme somatic denervation was observed in all patients at both proximal (fibers/mm, RFC1 cases 0.0 vs. HCs 20.5, p < 0.0001) and distal sites (fibers/mm, RFC1 cases 0.0 vs. HCs 13.1, p < 0.0001); instead only a slight decrease was observed in cholinergic and adrenergic innervation of autonomic structures. CONCLUSIONS: RFC1 disease is characterized by a severe and widespread somatic SFN. Skin denervation may potentially represent the earliest feature and drive towards the suspicion of this disorder.
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Vestibulopatia Bilateral , Ataxia Cerebelar , Neuralgia , Neuropatia de Pequenas Fibras , Humanos , Pessoa de Meia-Idade , Ataxia Cerebelar/genética , Vestibulopatia Bilateral/complicações , Estudos Retrospectivos , Fibras NervosasRESUMO
Complement C3 was originally regarded as a serum effector protein, although recent data has emerged suggesting that intracellular C3 can also regulate basic cellular processes. Despite the growing interest in intracellular C3 functions, the mechanism behind its generation has not been demonstrated. In this study we show that C3 can be expressed from an alternative translational start site, resulting in C3 lacking the signal peptide, which is therefore translated in the cytosol. In contrast to the secreted form, alternatively translated cytosolic C3 is not glycosylated, is present mainly in a reduced state, and is turned over by the ubiquitin-proteasome system. C3 can also be retrotranslocated from the endoplasmic reticulum into the cytosol, structurally resembling secreted C3. Finally, we demonstrate that intracellular cytosolic C3 can opsonize invasive Staphylococcus aureus within epithelial cell, slowing vacuolar escape as well as impacting bacterial survival on subsequent exposure to phagocytes. Our work therefore reveals the existence and origin of intracellular, cytosolic C3, and demonstrates functions for cytosolic C3 in intracellular detection of cytoinvasive pathogens.
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Complemento C3 , Complexo de Endopeptidases do Proteassoma , Bactérias/metabolismo , Complemento C3/metabolismo , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismoRESUMO
INTRODUCTION: The purpose of this study was to determine if conjunctival lymphangiogenesis can be induced using adenoviral delivery of vascular endothelial growth factor C (VEGF-C). METHODS: Seventeen New Zealand white rabbits received a subconjunctival injection containing 3.5 × 107 plaque-forming units of an adenoviral vector containing the gene-encoding VEGF-C (Ad-VEGF-C). The contralateral eye was used for control experiment (the same volume of either saline or an empty vector). After 2 weeks, the animals were examined with trypan blue conjunctival lymphangiography, and the eyes were harvested for histology and immunohistochemistry (podoplanin and CD31). RESULTS: Trypan blue conjunctival lymphangiography revealed significantly more extensive conjunctival vessel network in the Ad-VEGF-C group compared with control: 1.35 ± 0.67 versus 0.28 ± 0.17 vessel length/analysed area (p = <0.0001). This finding was confirmed with immunohistochemistry, where a significant increase in the number of lymphatic vessels was found compared to control; 34 ± 9 per mm2 versus 13 ± 8 per mm2 (p = 0.0019). Furthermore, there was a significant increase in lymphatic cross-sectional area; 32,500 ± 7,900 µm2 per mm2 versus 17,600 ± 9,700 µm2 per mm2 (p = 0.0149). Quantification of blood vessels revealed no significant difference in blood vessel density between Ad-VEGF-C and control; 19 ± 9 per mm2 versus 14 ± 8 per mm2 (p = 0.1971). There was no significant difference in total blood vessel area; 13,200 ± 7,600 µm2 per mm2 versus 7,100 ± 3,000 µm2 per mm2 (p = 0.0715). Eyes treated with an adenoviral vector (VEGF-C or empty vector) responded with a reactive cellular response, predominantly lymphocytes, towards the vector. CONCLUSION: The study demonstrates the feasibility of inducing conjunctival lymphangiogenesis with a single subconjunctival injection of Ad-VEGF-C. Future studies will explore how this can be used with a therapeutic purpose.
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Linfangiogênese , Fator C de Crescimento do Endotélio Vascular , Coelhos , Animais , Fator C de Crescimento do Endotélio Vascular/genética , Linfangiogênese/fisiologia , Azul Tripano , Túnica ConjuntivaRESUMO
OBJECTIVE: Cataract surgery remains the sole method to resolve blindness secondary to cataract formation. One complication includes fibrin web formation post-operatively. This study aimed to investigate the presence of endotoxin within materials used during cataract surgery as a possible cause of fibrin web phenomenon. METHODS: Preservative-free epinephrine, heparin, viscoelastic devices, and intraocular lenses were collected for evaluation. Various manufacturers and manufacturing lot numbers were used when available. Viscosity of viscoelastics was reduced by incubating samples with human recombinant hyaluronidase. Intraocular product (IOL) packaging fluid was collected and stored for testing. The IOLs were then washed with a sterile balanced salt solution, incubated at 37°C for 48 h, and then fluid was collected for testing to mimic intraocular placement. Samples were tested using a commercially available rFC kit. Fluorescence was measured at time zero and after 1 h using a fluorescence microplate reader. The change in fluorescence was corrected for blank fluorescence and plotted to a standard curve. RESULTS: Endotoxin levels were below the limit of detection (0.05 EU/mL) in all samples. Incubation of IOLs at intraocular temperature did not increase extraction of endotoxin. CONCLUSION: Endotoxin was not identified in any tested sample, including those used in cases of fibrin web formation post-phacoemulsification. As fibrin webs are often observed episodically, it is possible that endotoxin levels may vary between batches, or that endotoxin is not related to fibrin formation.
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The Bacterial Endotoxins Test (BET) is a critical safety test that is used to detect bacterial endotoxins, which are the major contributor to fever-inducing contamination risks known as pyrogens. All parenteral therapies, including every lot of injected drugs, vaccines, medical devices, must be tested for pyrogens to ensure patient safety. Bacterial endotoxins test methods were developed as a highly sensitive detection method for bacterial endotoxins, after the discovery of a clotting cascade in horseshoe crab blood. However, horseshoe crab species are limited to some inshore coastal habitats along the Atlantic coast of the USA and others throughout Asia. Fully functional horseshoe crab clotting factors can be manufactured via recombinant protein production, and several BET methods featuring recombinant horseshoe crab proteins have now been developed for commercial use. Recombinant Bacterial Endotoxins Test (rBET) methods based on the use of recombinant Factor C (rFC) were established in the European Pharmacopoeia - however, these methods have not yet been granted compendial status in the United States Pharmacopoeia (USP). In order to facilitate dialogue between stakeholders, the Physicians Committee for Responsible Medicine hosted two virtual roundtable discussions on the perceived barriers to the use of rBET methods for US FDA requirements. Stakeholders agreed that multiple rFC-based methods have been demonstrated to have suitable analytical performance, as described in ICH Q2 on the Validation of Analytical Procedures and USP <1225> on the Validation of Compendial Procedures. United States Pharmacopoeia compendial inclusion of the rFC-based and other rBET methods was favoured, in order to reduce the additional burdens created by a lack of global harmonisation on BET testing requirements.
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Pirogênios , Vacinas , Animais , Humanos , Segurança de Equipamentos , Endotoxinas/metabolismo , Caranguejos Ferradura/metabolismo , Vacinas/metabolismo , Teste do Limulus/métodosRESUMO
Lactoferrin (Lf) is a multifunctional protein from the transferrin family. Of particular interest is the ability of Lf to affect a wide range of neuronal processes by modulating the expression of genes involved in long-term neuroplasticity. The expression of the immediate early gene c-fos that is rapidly activated in response to external influences, and its product, transcription factor c-Fos, is widely used as a marker of long-term neuronal plasticity. The present study aims to examine the effect of human Lf on the induction of transcription factor c-Fos in the primary mouse neuronal cultures after stimulation and to determine the cellular localization of human Lf and its colocalization with induced c-Fos protein. Primary dissociated cultures of hippocampal cells were obtained from the brains of newborn C57BL/6 mice (P0-P1). On day 7 of culturing, human Lf was added to the medium. After 24 h (day 8 in culture), c-Fos protein was induced in cells by triple application of 50 mM KCl. c-Fos content was analyzed using the immunofluorescent method 2 h after stimulation. Stimulation promoted exogenous Lf translocation into the nuclei of cultured neuronal cells, which correlated with increased induction of transcription factor c-Fos and was accompanied by nuclear colocalization of these proteins. These results attest to the potential of Lf as a modulator of neuronal processes and open up new prospects in studying the mechanisms of the regulatory effects of lactoferrin on cell function.
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Lactoferrina , Proteínas Proto-Oncogênicas c-fos , Camundongos , Humanos , Animais , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Lactoferrina/farmacologia , Lactoferrina/genética , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , Neurônios/metabolismoRESUMO
BACKGROUND: Osteoarthritis (OA) affects the entire joint, initially with a low degree of inflammation. Synovitis is correlated with the severity of OA clinical symptoms and cartilage degradation. The synovial lymphatic system (SLS) plays a prominent role in clearing macromolecules within the joint, including the pro-inflammatory cytokines in arthritic status. Scattered evidence shows that impaired SLS drainage function leads to the accumulation of inflammatory factors in the joint and aggravates the progression of OA, and the role of SLS function in OA is less studied. DESIGN: This review summarizes the current understanding of synovial lymphatic function in OA progression and potential regulatory pathways and aims to provide a framework of knowledge for the development of OA treatments targeting lymphatic structure and functions. RESULTS: SLS locates in the subintima layer of the synovium and consists of lymphatic capillaries and lymphatic collecting vessels. Vascular endothelial growth factor C (VEGF-C) is the most critical regulating factor of lymphatic endothelial cells (LECs) and SLS. Nitric oxide production-induced impairment of lymphatic muscle cells (LMCs) and contractile function may attribute to drainage dysfunction. Preclinical evidence suggests that promoting lymphatic drainage may help restore intra-articular homeostasis to attenuate the progression of OA. CONCLUSION: SLS is actively involved in the homeostatic maintenance of the joint. Understanding the drainage function of the SLS at different stages of OA development is essential for further design of therapies targeting the function of these vessels.
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Vasos Linfáticos , Osteoartrite , Células Endoteliais , Humanos , Sistema Linfático , Osteoartrite/metabolismo , Membrana Sinovial/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismoRESUMO
Hereby, we aimed to investigate the expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and Vascular Endothelial Factor-C (VEGF-C) besides the methylation of PTGS2 in AML patients. VEGF-C and PTGS2 expression analysis were evaluated in newly diagnosed AML patients and healthy controls by quantitative Reverse Transcriptase PCR method. Also, PTGS2 methylation status was evaluated by Methylation-Sensitive High-Resolution Melting Curve Analysis (MS-HRM). While 34% of patients were female, the mean age of the patients was 43.41 ± 17.60 years suffering mostly from M4 (48.21%) type of AML. Although methylation level between patients and controls was not significantly different, none of the normal controls showed methylation in the PTGS2 promoter. PTGS2 and VEGF-C levels were elevated in AML cases and correlated with WBC, Platelet, and Hemoglobin levels. The survival of patients with overexpressed VEGF-C and PTGS2 was poorer than others. It can be concluded that PTGS2 and especially VEGF-C expression but not PTGS2 methylation can be considered as diagnostic biomarkers for AML.
Assuntos
Leucemia Mieloide Aguda , Fator C de Crescimento do Endotélio Vascular , Adulto , Biomarcadores , Ciclo-Oxigenase 2/genética , Metilação de DNA/genética , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Fator C de Crescimento do Endotélio Vascular/genéticaRESUMO
Vascular dementia (VaD) is a serious global health issue and type 2 diabetes mellitus (T2DM) patients are at higher risk. Palm oil tocotrienol-rich fraction (TRF) exhibits neuroprotective properties; however, its effect on VaD is not reported. Hence, we evaluated TRF effectiveness in T2DM-induced VaD rats. Rats were given a single dose of streptozotocin (STZ) and nicotinamide (NA) to develop T2DM. Seven days later, diabetic rats were given TRF doses of 30, 60, and 120 mg/kg orally for 21 days. The Morris water maze (MWM) test was performed for memory assessment. Biochemical parameters such as blood glucose, plasma homocysteine (HCY) level, acetylcholinesterase (AChE) activity, reduced glutathione (GSH), superoxide dismutase (SOD) level, and histopathological changes in brain hippocampus and immunohistochemistry for platelet-derived growth factor-C (PDGF-C) expression were evaluated. VaD rats had significantly reduced memory, higher plasma HCY, increased AChE activity, and decreased GSH and SOD levels. However, treatment with TRF significantly attenuated the biochemical parameters and prevented memory loss. Moreover, histopathological changes were attenuated and there was increased PDGF-C expression in the hippocampus of VaD rats treated with TRF, indicating neuroprotective action. In conclusion, this research paves the way for future studies and benefits in understanding the potential effects of TRF in VaD rats.
Assuntos
Demência Vascular , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Tocotrienóis , Ratos , Animais , Óleo de Palmeira , Tocotrienóis/farmacologia , Tocotrienóis/uso terapêutico , Demência Vascular/tratamento farmacológico , Demência Vascular/etiologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Acetilcolinesterase/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Superóxido Dismutase/metabolismo , Aprendizagem em LabirintoRESUMO
OBJECTIVE: To analyze the clinical treatment results of male infertility caused by Y chromosome azoospermia factor c region(AZFc) deletion after synchronous micro-dissection testicular sperm extraction (micro-TESE) and intracytoplasmic sperm injection (ICSI) and to guide the treatment of infer- tile patients caused by AZFc deletion. METHODS: The clinical data of infertile patients with AZFc deletion who underwent synchronous micro-TESE in Peking University Third Hospitalfrom January 2015 to December 2019 were retrospectively analyzed. The clinical outcomes of ICSI in the patients who successfully obtained sperm were followed up and we compared the outcomes between the first and second synchronous procedures, including fertilization rate, high-quality embryo rate, clinical pregnancy rate, abortion rate and live birth rate. RESULTS: A total of 195 male infertile patients with AZFc deletion underwent micro-TESE. Fourteen patients were cryptozoospermia and their sperms were successfully obtained in all of them during the operation, and the sperm retrieval rate (SRR) was 100%(14/14). The remaining 181 cases were non obstructive azoospermia, and 122 cases were successfully found the sperm, the SRR was 67.4%(122/181). The remaining 59 patients with NOA could not found mature sperm during micro-TESE, accounting for 32.6% (59/181). We followed up the clinical treatment outcomes of the patients with successful sperm retrieved by synchronous micro-TESE and 99 patients were enrolled in the study. A total of 118 micro-TESE procedures and 120 ICSI cycles were carried out. Finally 38 couples successfully gave birth to 22 male and 22 female healthy infants, with a cumulative live birth rate of 38.4% (38/99). In the fresh-sperm ICSI cycle of the first and second synchronous operation procedures, the high-quality embryo rate, clinical pregnancy rate of the fresh embryo transfer cycle and live birth rate of the oocyte retrieve cycle were 47.7% vs. 50.4%, 40.5% vs. 50.0%, and 28.3% vs. 41.2%, respectively. The second operation group was slightly higher than that of the first synchronous operation group, but there was no significant difference between the groups. CONCLUSION: Male infertility patients caused by AZFc deletion have a high probability of successfully obtaining sperm in testis through micro-TESE for ICSI and give birth to their own offspring with their own biological characteristics. For patients who failed in the first synchronous procedure, they still have the opportunity to successfully conceive offspring through reoperation and ICSI.