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1.
J Immunol ; 212(12): 1971-1980, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709159

RESUMEN

Most pancreatic islets are destroyed immediately after intraportal transplantation by an instant blood-mediated inflammatory reaction (IBMIR) generated through activation of coagulation, complement, and proinflammatory pathways. Thus, effective mitigation of IBMIR may be contingent on the combined use of agents targeting these pathways for modulation. CD47 and thrombomodulin (TM) are two molecules with distinct functions in regulating coagulation and proinflammatory responses. We previously reported that the islet surface can be modified with biotin for transient display of novel forms of these two molecules chimeric with streptavidin (SA), that is, thrombomodulin chimeric with SA (SA-TM) and CD47 chimeric with SA (SA-CD47), as single agents with improved engraftment following intraportal transplantation. This study aimed to test whether islets can be coengineered with SA-TM and SA-CD47 molecules as a combinatorial approach to improve engraftment by inhibiting IBMIR. Mouse islets were effectively coengineered with both molecules without a detectable negative impact on their viability and metabolic function. Coengineered islets were refractory to destruction by IBMIR ex vivo and showed enhanced engraftment and sustained function in a marginal mass syngeneic intraportal transplantation model. Improved engraftment correlated with a reduction in intragraft innate immune infiltrates, particularly neutrophils and M1 macrophages. Moreover, transcripts for various intragraft procoagulatory and proinflammatory agents, including tissue factor, HMGB1 (high-mobility group box-1), IL-1ß, IL-6, TNF-α, IFN-γ, and MIP-1α, were significantly reduced in coengineered islets. These data demonstrate that the transient codisplay of SA-TM and SA-CD47 proteins on the islet surface is a facile and effective platform to modulate procoagulatory and inflammatory responses with implications for both autologous and allogeneic islet transplantation.


Asunto(s)
Antígeno CD47 , Inflamación , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Ratones Endogámicos C57BL , Trombomodulina , Animales , Masculino , Ratones , Antígeno CD47/inmunología , Antígeno CD47/metabolismo , Inflamación/inmunología , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/metabolismo , Trasplante de Islotes Pancreáticos/métodos , Estreptavidina
2.
Epidemiol Infect ; 152: e14, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38178722

RESUMEN

Using two rounds of serosurveillance, we aimed to observe the COVID-19 vaccination status and the dynamics of antibody responses to different vaccines among urban slum and non-slum populations of Bangladesh. Adults (>18 years) and children (10-17 years) were enrolled in March and October 2022. Data including COVID-19 vaccine types and dosage uptake were collected. SARS-CoV-2 spike (S)-specific antibodies were measured in blood. The proportion of vaccinated children was significantly lower among slum than non-slum populations. Two doses of vaccines showed an increase in the level of anti-S-antibodies up to 2 months, followed by reduced levels at 2-6 months and a resurgence at 6-12 months. Children showed significantly higher anti-S-antibodies after two doses of the Pfizer-BioNTech vaccine than adults; however, after 6 months, the level of antibodies declined in younger children (10 - < 12 years). In a mixed vaccine approach, mRNA vaccines contributed to the highest antibody response whether given as the first two doses or as the third dose. Our findings emphasized the need for increasing the coverage of COVID-19 vaccination among slum children and booster dosing among all children. The use of mRNA vaccines in the mixed vaccination approach was found to be useful in boosting the antibody response to SARS-CoV-2.


Asunto(s)
COVID-19 , Áreas de Pobreza , Adulto , Niño , Humanos , Vacunas contra la COVID-19 , Población Urbana , Bangladesh/epidemiología , Vacunas de ARNm , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2
3.
Saudi Pharm J ; 32(1): 101916, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38178850

RESUMEN

Glycation is the non-enzymatic adduct formation between reducing sugars or dicarbonyls with proteins and is a crucial molecular event under hyperglycaemic conditions of diabetes. The accumulation of advanced glycation end products (AGEs) due to glycation of proteins has been implicated in several diseases associated with ageing and diabetes. Thus, investigating the antiglycation potential of some trace metal ions (Manganese; Mn2+, and Zinc; Zn2+) and polyphenolic extract of chickpea seeds (PEC) on the methylglyoxal (MGO) induced glycation of a phytocystatin isolated from chickpea was taken up to find an inexpensive and non-toxic therapeutic means of medicating protein glycation and associated diabetic complications. The current study focused on the comparative analyses of these micronutrients and herbal extracts in inhibiting protein glycation and AGEs formation in a quest to develop nutraceuticals for managing diabetes. The effect of metals (Mn2+, Zn2+) and PEC on protein glycation was assessed by different techniques, i.e., glycation-specific AGE fluorescence and absorbance, thiol protease inhibitory activity assay, and conformational alterations by spectroscopic assays. This study revealed the significant anti-glycation potencies of Mn2+, Zn2+, and PEC against the MGO-induced glycation of CPC, which might pave the way for resolving pathological complications of diabetes by combining higher levels of efficacy, selectivity, and safety in humans. Moreover, characterization and identification of different AGEs formed during the glycation process in diabetics was done to apply the same for determining the onset of glycation at the early stage so that appropriate steps be taken to address the menace of diabetic complications.

4.
Semin Cancer Biol ; 86(Pt 2): 624-644, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35378274

RESUMEN

Cancer has complex pathophysiology and is one of the primary causes of death and morbidity across the world. Chemotherapy, targeted therapy, radiation therapy, and immunotherapy are examples of traditional cancer treatments. However, these conventional treatment regimens have many drawbacks, such as lack of selectivity, non-targeted cytotoxicity, insufficient drug delivery at tumor sites, and multi-drug resistance, leading to less potent/ineffective cancer treatment. Due to its immanent biophysical property and ability to change in numerous ways, nano-technology has completely transformed how cancer is identified and treated in recent years. Furthermore, nanotechnology providing solutions to these restrictions and boosting cancer therapy. Nanoparticles are widely used nanomedicine platform in cancer immunotherapy due to their excellent physicochemical properties that include size, shape, and surface features, resulting into desirable biological interactions and have been categorized into several types. Nanoparticles can also be potentially be up taken by antigen-presenting cells that promote the cytosolic delivery of encapsulated antigens and adjuvants. Furthermore, nanoparticles can be fine-tuned and functionalized with specific moieties to promote their efficacy in targeting and delivering cargo materials to specific locations. In this review, we summarized and discussed nanoparticles and potential features to be used as carriers in cancer immunotherapy, the current status of different types of nanoparticles, and the importance of their functionalization. Furthermore, we have also discussed nanoparticles-based nanomedicine in targeted delivery of encapsulated cancer immunotherapeutic and their involvement in the modulation of the tumor microenvironment, promoting cancer immunotherapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Nanomedicina/métodos , Inmunoterapia/métodos , Nanopartículas/química , Microambiente Tumoral , Neoplasias/tratamiento farmacológico
5.
Am J Transplant ; 23(5): 619-628, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36863480

RESUMEN

The instant blood-mediated inflammatory reaction (IBMIR) is initiated by innate immune responses that cause substantial islet loss after intraportal transplantation. Thrombomodulin (TM) is a multifaceted innate immune modulator. In this study, we report the generation of a chimeric form of thrombomodulin with streptavidin (SA-TM) for transient display on the surface of islets modified with biotin to mitigate IBMIR. SA-TM protein expressed in insect cells showed the expected structural and functional features. SA-TM converted protein C into activated protein C, blocked phagocytosis of xenogeneic cells by mouse macrophages and inhibited neutrophil activation. SA-TM was effectively displayed on the surface of biotinylated islets without a negative effect on their viability or function. Islets engineered with SA-TM showed improved engraftment and established euglycemia in 83% of diabetic recipients when compared with 29% of recipients transplanted with SA-engineered islets as control in a syngeneic minimal mass intraportal transplantation model. Enhanced engraftment and function of SA-TM-engineered islets were associated with the inhibition of intragraft proinflammatory innate cellular and soluble mediators of IBMIR, such as macrophages, neutrophils, high-mobility group box 1, tissue factor, macrophage chemoattractant protein-1, interleukin-1ß, interleukin-6, tumor necrosis factor-α, interferon-γ. Transient display of SA-TM protein on the islet surface to modulate innate immune responses causing islet graft destruction has clinical potential for autologous and allogeneic islet transplantation.


Asunto(s)
Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Animales , Ratones , Proteína C , Trombomodulina , Trasplante Homólogo
6.
Cancer Immunol Immunother ; 72(11): 3567-3579, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37605009

RESUMEN

Immunotherapy utilizing checkpoint inhibitors has shown remarkable success in the treatment of cancers. In addition to immune checkpoint inhibitors, immune co-stimulation has the potential to enhance immune activation and destabilize the immunosuppressive tumor microenvironment. CD137, also known as 4-1BB, is one of the potent immune costimulatory receptors that could be targeted for effective immune co-stimulation. The interaction of the 4-1BB receptor with its natural ligand (4-1BBL) generates a strong costimulatory signal for T cell proliferation and survival. 4-1BBL lacks costimulatory activity in soluble form. To obtain co-stimulatory activity in soluble form, a recombinant 4-1BBL protein was generated by fusing the extracellular domains of murine 4-1BBL to a modified version of streptavidin (SA-4-1BBL). Treatment with SA-4-1BBL inhibited the development of lung tumors in A/J mice induced by weekly injections of the tobacco carcinogen NNK for eight weeks. The inhibition was dependent on the presence of T cells and NK cells; depletion of these cells diminished the SA-4-1BBL antitumor protective effect. The number of lung tumor nodules was significantly reduced by the administration of SA-4-1BBL to mice during ongoing exposure to NNK. The data presented in this paper suggest that utilizing an immune checkpoint stimulator as a single agent generate a protective immune response against lung cancer in the presence of a carcinogen. More broadly, this study suggests that immune checkpoint stimulation can be extended to a number of other cancer types, including breast and prostate cancers, for which improved diagnostics can detect disease at the preneoplastic stage.


Asunto(s)
Neoplasias Pulmonares , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral , Ratones , Animales , Carcinógenos/toxicidad , Linfocitos T , Ligando 4-1BB , Proteínas Recombinantes , Neoplasias Pulmonares/inducido químicamente , Microambiente Tumoral
7.
Mol Biol Rep ; 50(5): 4447-4457, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37014566

RESUMEN

BACKGROUND: Ovarian cancer leads to devastating outcomes, and its treatment is highly challenging. At present, there is a lack of clinical symptoms, well-known sensitivity biomarkers, and patients are diagnosed at an advanced stage. Currently, available therapeutics against ovarian cancer are inefficient, costly, and associated with severe side effects. The present study evaluated the anticancer potential of zinc oxide nanoparticles (ZnO NPs) that were successfully biosynthesized in an ecofriendly mode using pumpkin seed extracts. METHODS AND RESULTS: The anticancer potential of the biosynthesized ZnO NPs was assessed using an in vitro human ovarian teratocarcinoma cell line (PA-1) by well-known assays such as MTT assay, morphological alterations, induction of apoptosis, measurement of reactive oxygen species (ROS) production, and inhibition of cell adhesion/migration. The biogenic ZnO NPs exerted a high level of cytotoxicity against PA-1 cells. Furthermore, the ZnO NPs inhibited cellular adhesion and migration but induced ROS production and cell death through programmed cell death. CONCLUSION: The aforementioned anticancer properties highlight the therapeutic utility of ZnO NPs in ovarian cancer treatment. However, further research is recommended to envisage their mechanism of action in different cancer models and validation in a suitable in vivo system.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Neoplasias Ováricas , Teratocarcinoma , Óxido de Zinc , Femenino , Humanos , Óxido de Zinc/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Ováricas/tratamiento farmacológico
8.
Arch Environ Contam Toxicol ; 84(2): 179-187, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36586095

RESUMEN

In this study, we measured various parameters of oxidative stress, immune response, and abnormalities in the erythrocyte nucleus of Labeo rohita inhabiting the polluted Kshipra River, India. The river water contains heavy metals in this order: Ni > Fe > Cd > Cr > Mn > Zn > Cu. Fe showed the highest accumulation in gills, liver, and gut, whereas Ni (gills and gut) and Cd (liver) were lowest accumulated. The superoxide dismutase (SOD) and catalase (CAT) were found to be increased significantly (p < 0.05) in the gills (SOD: 211%; CAT: 150%), liver (SOD: 447%; CAT: 304%), and gut (SOD: 98.11%; CAT: 58.69%) in comparison with the reference fish. However, glutathione S transferase (GST) showed significantly (p < 0.05) higher activity in the gills (25.5%) but lower activity in the liver (- 49.22%) and the gut (- 30.57%). Moreover, reduced glutathione (GSH) decreased significantly (p < 0.05) in the gills (- 46.66%), liver (- 33.20%), and gut (- 39.87%). Despite the active response of the antioxidant enzymes, the highest lipid peroxidation was observed in the liver (463%). The effect of heavy metals was also observed on the immunity of the fish, causing immunosuppression as evident by significantly (p < 0.05) lower values of acid phosphatase (- 50%), myeloperoxidase (- 48.33%), and nitric oxide synthase (- 50%) in serum. Histopathological findings showed gill lamellae shortening, hyperplasia, club-shaped lamellar tip in exposed gills and necrosis, vacuolization, and pyknosis in the exposed liver. Furthermore, polluted river water was also found to induce micronuclei (2.1%) and lobed nuclei (0.72%) in erythrocytes (0.65%). These results indicate the potential of heavy metal-induced oxidative stress and other forms of stress in inhabiting fish, highlighting the need to control the pollution of this river water.


Asunto(s)
Cyprinidae , Metales Pesados , Contaminantes Químicos del Agua , Animales , Ríos , Cadmio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Metales Pesados/análisis , Contaminación del Agua , Superóxido Dismutasa/metabolismo , Catalasa/metabolismo , Estrés Oxidativo , Cyprinidae/metabolismo , Oxidación-Reducción , Hígado/metabolismo , Agua , Branquias/metabolismo , Peroxidación de Lípido
9.
Pancreatology ; 22(5): 553-563, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35570091

RESUMEN

Chronic pancreatitis (CP) is an irreversible fibro-inflammatory disease of the pancreas with no current targeted therapy. Pirfenidone, an anti-fibrotic and anti-inflammatory drug, is FDA approved for treatment of Idiopathic Pulmonary Fibrosis (IPF). Its efficacy in ameliorating CP has never been evaluated before. We recently reported that pirfenidone improves acute pancreatitis in mouse models. The aim of the current study was to evaluate the therapeutic efficacy of pirfenidone in mouse models of CP. We used caerulein and L-arginine models of CP and administered pirfenidone with ongoing injury, or in well-established disease. We evaluated for fibrosis by Sirius-red staining for collagen, immunohistochemistry, western blotting, and qPCR for fibrosis markers to show the salutary effects of pirfenidone in CP. Our results suggest that treatment with pirfenidone ameliorated CP related changes in the pancreas (i.e., atrophy, acinar cell loss, fibrosis, and inflammation) not only when administered with ongoing injury, but also in well-established models of caerulein as well as L-arginine induced CP. It reduces the pro-fibrotic phenotype of macrophages (in-vivo and in-vitro), reduces macrophage infiltration into the pancreas and alters the intra-pancreatic cytokine milieu preceding changes in histology. The therapeutic effect of pirfenidone is abrogated in absence of macrophages. Furthermore, it reduces collagen secretion, cytokine levels and fibrosis markers in pancreatic stellate cells in-vitro. As it is FDA approved, our findings in mouse models simulating clinical presentation of patients to the clinic, can be used as the basis of a clinical trial evaluating the efficacy of this drug as a therapeutic agent for CP.


Asunto(s)
Ceruletida , Pancreatitis Crónica , Enfermedad Aguda , Animales , Arginina , Colágeno/efectos adversos , Citocinas , Modelos Animales de Enfermedad , Fibrosis , Humanos , Ratones , Pancreatitis Crónica/patología , Piridonas
10.
Int J Mol Sci ; 22(22)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34830339

RESUMEN

Cancer is, globally, one of the main causes of death. Even though various therapies are available, they are still painful because of their adverse side effects. Available treatments frequently fail due to unpromising responses, resistance to classical anticancer drugs, radiation therapy, chemotherapy, and low accessibility to tumor tissues. Developing novel strategies to minimize adverse side effects, improve chemotherapy sensitivity, and control cancer progression is needed. Many studies have suggested small dietary molecules as complementary treatments for cancer patients. Different components of herbal/edible plants, known as flavonoids, have recently garnered attention due to their broad biological properties (e.g., antioxidant, antiviral, antimicrobial, anti-inflammatory, anti-mutagenic, anticancer, hepatoprotective, and cardioprotective). These flavonoids have shown anticancer activity by affecting different signaling cascades. This article summarizes the key progress made in this area and discusses the role of flavonoids by specifically inhibiting the PI3K/Akt/mTOR pathway in various cancers.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Flavonoides/farmacología , Neoplasias/prevención & control , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/clasificación , Quimioprevención/métodos , Flavonoides/química , Flavonoides/clasificación , Frutas/química , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Verduras/química
11.
Gastroenterology ; 155(1): 33-37.e6, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29630898

RESUMEN

We studied the effects of gut microbiome depletion by oral antibiotics on tumor growth in subcutaneous and liver metastases models of pancreatic cancer, colon cancer, and melanoma. Gut microbiome depletion significantly reduced tumor burden in all the models tested. However, depletion of gut microbiome did not reduce tumor growth in Rag1-knockout mice, which lack mature T and B cells. Flow cytometry analyses demonstrated that gut microbiome depletion led to significant increase in interferon gamma-producing T cells with corresponding decrease in interleukin 17A and interleukin 10-producing T cells. Our results suggest that gut microbiome modulation could emerge as a novel immunotherapeutic strategy.


Asunto(s)
Disbiosis/inmunología , Microbioma Gastrointestinal/inmunología , Metástasis de la Neoplasia/inmunología , Neoplasias/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Antibacterianos/farmacología , Carcinoma/secundario , Línea Celular Tumoral , Neoplasias del Colon/patología , Modelos Animales de Enfermedad , Microbioma Gastrointestinal/efectos de los fármacos , Interferón gamma/inmunología , Interleucina-10/inmunología , Interleucina-17/inmunología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/secundario , Melanoma/inmunología , Melanoma/secundario , Melanoma Experimental/inmunología , Melanoma Experimental/secundario , Ratones , Ratones Noqueados , Trasplante de Neoplasias , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Neoplasias de los Tejidos Blandos/inmunología , Neoplasias de los Tejidos Blandos/secundario , Linfocitos T/inmunología , Microambiente Tumoral/inmunología
13.
Vaccines (Basel) ; 12(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543974

RESUMEN

Natural 4-1BBL (CD137L) is a cell membrane-bound protein critical to the expansion, effector function, and survival of CD8+ T cells. We reported the generation of an active soluble oligomeric construct, SA-4-1BBL, with demonstrated immunoprevention and immunotherapeutic efficacy in various mouse tumor models. Herein, we developed an oncolytic adenovirus (OAd) for the delivery and expression of SA-4-1BBL (OAdSA-4-1BBL) into solid tumors for immunotherapy. SA-4-1BBL protein expressed by this construct produced T-cell proliferation in vitro. OAdSA-4-1BBL decreased cell viability in two mouse lung cancer cell lines, TC-1 and CMT64, but not in the non-cancerous lung MM14.Lu cell line. OAdSA-4-1BBL induced programmed cell death types I and II (apoptosis and autophagy, respectively), and autophagy-mediated adenosine triphosphate (ATP) release was also detected. Intratumoral injection of OAdSA-4-1BBL efficiently expressed the SA-4-1BBL protein in the tumors, resulting in significant tumor suppression in a syngeneic subcutaneous TC-1 mouse lung cancer model. Tumor suppression was associated with a higher frequency of dendritic cells and an increased infiltration of cytotoxic CD8+ T and NK cells into the tumors. Our data suggest that OAdSA-4-1BBL may present an efficacious alternative therapeutic strategy against lung cancer as a standalone construct or in combination with other immunotherapeutic modalities, such as immune checkpoint inhibitors.

14.
PLoS One ; 18(11): e0293666, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37943817

RESUMEN

The primary objective of this study is to uncover novel therapeutic agents for the treatment of Glioblastoma Multiforme (GBM), a highly aggressive form of brain cancer, and Alzheimer's Disease (AD). Given the complexity and resistance associated with both conditions, the study underscores the imperative need for therapeutic alternatives that can traverse the biological intricacies inherent in both neuro-oncological and neurodegenerative disorders. To achieve this, a meticulous, target-based virtual screening was employed on an ensemble of 50 flavonoids and polyphenol derivatives primarily derived from plant sources. The screening focused predominantly on molecular targets pertinent to GBM but also evaluated the potential overlap with neural pathways involved in AD. The study utilized molecular docking and Molecular Dynamic (MD) simulation techniques to analyze the interaction of these compounds with a key biological target, protein tyrosine phosphatase receptor-type Z (PTPRZ). Out of the 50 compounds examined, 10 met our stringent criteria for binding affinity and specificity. Subsequently, the highest value of binding energy was observed for the synergistic binding of luteolin and ferulic acid with the value of -10.5 kcal/mol. Both compounds exhibited inherent neuroprotective properties and demonstrated significant potential as pathway inhibitors in GBM as well as molecular modulators in AD. Drawing upon advanced in-silico cytotoxicity predictions and sophisticated molecular modeling techniques, this study casts a spotlight on the therapeutic capabilities of polyphenols against GBM. Furthermore, our findings suggest that leveraging these compounds could catalyze a much-needed paradigm shift towards more integrative therapeutic approaches that span the breadth of both neuro-oncology and neurodegenerative diseases. The identification of cross-therapeutic potential in flavonoids and polyphenols could drastically broaden the scope of treatment modalities against both fatal diseases.


Asunto(s)
Angelica sinensis , Cannabis , Glioblastoma , Humanos , Simulación del Acoplamiento Molecular , Luteolina/farmacología , Glioblastoma/tratamiento farmacológico , Simulación de Dinámica Molecular
15.
Front Pharmacol ; 14: 1236173, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900167

RESUMEN

Cancer has been one of the leading causes of mortality worldwide over the past few years. Some progress has been made in the development of more effective cancer therapeutics, resulting in improved survival rates. However, the desired outcome in the form of successful treatment is yet to be achieved. There is high demand for the development of innovative, inexpensive, and effective anticancer treatments using natural resources. Natural compounds have been increasingly discovered and used for cancer therapy owing to their high molecular diversity, novel biofunctionality, and minimal side effects. These compounds can be utilized as chemopreventive agents because they can efficiently inhibit cell growth, control cell cycle progression, and block several tumor-promoting signaling pathways. PI3K is an important upstream protein of the PI3K-Akt-mTOR pathway and a well-established cancer therapeutic target. This study aimed to explore the small molecules, natural flavonoids, viz. quercetin, luteolin, kaempferol, genistein, wogonin, daidzein, and flavopiridol for PI3Kγ kinase activity inhibition. In this study, the binding pose, interacting residues, molecular interactions, binding energies, and dissociation constants were investigated. Our results showed that these flavonoids bound well with PI3Kγ with adequate binding strength scores and binding energy ranging from (-8.19 to -8.97 Kcal/mol). Among the explored ligands, flavopiridol showed the highest binding energy of -8.97 Kcal/mol, dock score (-44.40), and dissociation constant term, pKd of 6.58 against PI3Kγ. Based on the above results, the stability of the most promising ligand, flavopiridol, against PI3Kγ was evaluated by molecular dynamics simulations for 200 ns, confirming the stable flavopiridol and PI3Kγ complex. Our study suggests that among the selected flavonoids specifically flavopiridol may act as potential inhibitors of PI3Kγ and could be a therapeutic alternative to inhibit the PI3Kγ pathway, providing new insights into rational drug discovery research for cancer therapy.

16.
Front Immunol ; 14: 1138145, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153623

RESUMEN

Leprosy is a chronic bacterial disease caused by Mycobacterium leprae. Leprosy patients have been found to have defects in T cells activation, which is critical to the clearance of the bacilli. Treg cell suppression is mediated by inhibitory cytokines such as IL10, IL-35 and TGF-ß and its frequency is higher in leprosy patients. Activation and overexpression of programmed death 1 (PD-1) receptor is considered to one of the pathways to inhibit T-cell response in human leprosy. In the current study we address the effect of PD-1 on Tregs function and its immuno-suppressive function in leprosy patients. Flow cytometry was used to evaluate the expression of PD-1 and its ligands on various immune cells T cells, B cells, Tregs and monocytes. We observed higher expression of PD-1 on Tregs is associated with lower production of IL-10 in leprosy patients. PD-1 ligands on T cells, B cells, Tregs and monocytes found to be higher in the leprosy patients as compared to healthy controls. Furthermore, in vitro blocking of PD-1 restores the Tregs mediated suppression of Teff and increase secretion of immunosuppressive cytokine IL-10. Moreover, overexpression of PD-1 positively correlates with disease severity as well as Bacteriological Index (BI) among leprosy patients. Collectively, our data suggested that PD-1 overexpression on various immune cells is associated with disease severity in human leprosy. Manipulation and inhibition of PD-1 signaling pathway on Tregs alter and restore the Treg cell suppression activity in leprosy patients.


Asunto(s)
Interleucina-10 , Lepra , Humanos , Interleucina-10/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Mycobacterium leprae , Linfocitos T Reguladores , Citocinas/metabolismo
17.
Healthcare (Basel) ; 11(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37239730

RESUMEN

OBJECTIVES: To examine the levels and socio-demographic differentials of: (a) reported COVID-like symptoms; and (b) seroprevalence data matched with COVID-like symptoms. METHODS: Survey data of reported COVID-like symptoms and seroprevalence were assessed by Roche Elecsys® Anti-SARS-CoV-2 immunoassay. Survey data of 10,050 individuals for COVID-like symptoms and seroprevalence data of 3205 individuals matched with COVID-like symptoms were analyzed using bivariate and multivariate logistic analysis. RESULTS: The odds of COVID-like symptoms were significantly higher for Chattogram city, for non-slum, people having longer years of schooling, working class, income-affected households, while for households with higher income had lower odd. The odds of matched seroprevalence and COVID-like symptoms were higher for non-slum, people having longer years of schooling, and for working class. Out of the seropositive cases, 37.77% were symptomatic-seropositive, and 62.23% were asymptomatic, while out of seronegative cases, 68.96% had no COVID-like symptoms. CONCLUSIONS: Collecting community-based seroprevalence data is important to assess the extent of exposure and to initiate mitigation and awareness programs to reduce COVID-19 burden.

18.
Front Nutr ; 9: 1078642, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36712528

RESUMEN

Pancreatic cancer remains a lethal disease and a major public health problem globally. Nuclear factor-kappa B (NF-κB) has been identified as a therapeutic target in several cancers and plays an important role in inflammatory responses. Many phytochemicals, including catechins, have been reported in the scientific literature with efficient anticancer potential and minimal side effects. This study aims to gain insights into the inhibitory mechanism of catechin derivatives epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) using in silico and in vitro studies especially considering NF-κB targeting. We explored the binding pose, interacting residues and molecular interactions for catechin derivatives with NF-κB. Docking analysis showed that the catechin derivatives acted as covalent inhibitors with the p65 subunit of NF-κB and interacted with other residues through non-bonding interactions and hydrogen bonds. Further, we validated the effect of EGCG on NF-κB activity in pancreatic cancer cell lines MIAPaCa-2 and SU 86.86. Our in vitro data showed EGCG effectively reduced cell growth and proliferation, induced apoptosis, and inhibited NF-κB activity in the studied cell lines. In addition, EGCG repressed the expression of NF-κB target genes including MMP9, MMP2, cMyc, and BCL-2. Thus, targeting NF-κB with EGCG could be a potential therapeutic alternative for pancreatic cancer treatment.

19.
Front Med (Lausanne) ; 9: 913848, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847777

RESUMEN

Malaria elimination is a global priority, which India has also adopted as a target. Despite the malaria control efforts like long-lasting insecticidal nets distribution, rounds of indoor residual spray, the introduction of bi-valent rapid diagnostic tests and artemisinin combination therapy, malaria remained consistent in Dolonibasti sub-center of Orang block primary health center (BPHC) under the district Udalguri, Assam state followed by abrupt rise in cases in 2018. Therefore, we aimed to investigate the factors driving the malaria transmission in the outbreak area of Dolonibasti sub-center. Malaria epidemiological data (2008-2018) of Udalguri district and Orang BPHC was collected. The annual (2011-2018) and monthly (2013-2018) malaria and meteorological data of Dolonibasti sub-center was collected. An entomological survey, Knowledge, Attitude and Practices study among malaria cases (n = 120) from Dolonibasti was conducted. In 2018, 26.1 % (2136/ 8188) of the population of Dolonibasti were found to be malaria positive, of which 55% were adults (n = 1176). Majority of cases were from tea tribe populations (90%), either asymptomatic or with fever only, 67.5 % (81/120) had experienced malaria infection during past years. The outbreak was characterized by a strong increase in cases in June 2018, high proportion of slide falciparum rate of 26.1% (other years average, 15.8%) and high proportion of P. falciparum of 81.2 % (other years average, 84.3%). Anopheles minimus s.l. was the major vector with 28.6% positivity and high larval density in paddy fields/ drainage area. Annual relative humidity was associated with rise in malaria cases, annual parasite incidence (rs = 0.69, 90%CI; p = 0.06) and slide positivity rate (rs = 0.83, 95%CI; p = 0.01). Older people were less educated (rs = -0.66; p < 0.001), had lesser knowledge about malaria cause (rs = -0.42; χ2=21.80; p < 0.001) and prevention (rs = -0.18; p = 0.04). Malaria control practices were followed by those having knowledge about cause of malaria (rs = 0.36; χ2 = 13.50; p < 0.001) and prevention (rs = 0.40; χ2 = 17.71; p < 0.001). Altogether, 84.6% (44/52) of the respondents did not use protective measures. We described a sudden increase in malaria incidence in a rural, predominantly tea tribe population group with high illiteracy rate and ignorance on protective measures against malaria. More efforts that are concerted needed to educate the community about malaria control practices.

20.
Microorganisms ; 10(2)2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35208844

RESUMEN

The ability to perform effectively in the gastrointestinal tract (GIT) is one of the most significant criteria in the selection of potential probiotic bacteria. Thus, the present study aimed to investigate the potential probiotic characteristics of some selected lactic acid bacteria (LAB) isolated from vegetable products. Probiotic characteristics included tolerance to acid and bile, cholesterol-removing ability, bile salt hydrolysis, resistance against lysozyme and antibiotics, production of exopolysaccharides (EPS), antimicrobial and hemolytic activities, and cell surface characteristics (auto-aggregation, co-aggregation, and hydrophobicity). The survival rate of isolates after G120 ranged from 8.0 to 8.6 Log10 CFU/mL. After the intestinal phase (IN-120), the bacterial count ranged from 7.3 to 8.5 Log10 CFU/mL. The bile tolerance rates ranged from 17.8 to 51.1%, 33.6 to 63.9%, and 55.9 to 72.5% for cholic acid, oxgall, and taurocholic acid, respectively. Isolates F1, F8, F23, and F37 were able to reduce cholesterol (>30%) from the broth. The auto-aggregation average rate increased significantly after 24 h for all isolates, while two isolates showed the highest hydrophobicity values. Moreover, isolates had attachment capabilities comparable to those of HT-29 cells, with an average of 8.03 Log10 CFU/mL after 2 h. All isolates were resistant to lysozyme and vancomycin, and 8 out of the 17 selected isolates displayed an ability to produce exopolysaccharides (EPS). Based on 16S rRNA sequencing, LAB isolates were identified as Enterococcus faecium, E. durans, E. lactis, and Pediococcus acidilactici.

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