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1.
Nature ; 633(8029): 327-331, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39169194

RESUMO

The elemental composition of the lunar surface provides insights into mechanisms of the formation and evolution of the Moon1,2. The chemical composition of lunar regolith have so far been precisely measured using the samples collected by the Apollo, Luna and Chang'e 5 missions, which are from equatorial to mid-latitude regions3,4; lunar meteorites, whose location of origin on the Moon is unknown5,6; and the in situ measurement from the Chang'e 3 and Chang'e 4 missions7-9, which are from the mid-latitude regions of the Moon. Here we report the first in situ measurements of the elemental abundances in the lunar southern high-latitude regions by the Alpha Particle X-ray Spectrometer (APXS) experiment10 aboard the Pragyan rover of India's Chandrayaan-3 mission. The 23 measurements in the vicinity of the Chandrayaan-3 landing site show that the local lunar terrain in this region is fairly uniform and primarily composed of ferroan anorthosite (FAN), a product of the lunar magma ocean (LMO) crystallization. However, observation of relatively higher magnesium abundance with respect to calcium in APXS measurements suggests the mixing of further mafic material. The compositional uniformity over a few tens of metres around the Chandrayaan-3 landing site provides an excellent ground truth for remote-sensing observations.

2.
J Biol Chem ; 300(1): 105528, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38043794

RESUMO

Parasitic flatworms cause various clinical and veterinary infections that impart a huge burden worldwide. The most clinically impactful infection is schistosomiasis, a neglected tropical disease caused by parasitic blood flukes. Schistosomiasis is treated with praziquantel (PZQ), an old drug introduced over 40 years ago. New drugs are urgently needed, as while PZQ is broadly effective it suffers from several limitations including poor efficacy against juvenile worms, which may prevent it from being completely curative. An old compound that retains efficacy against juvenile worms is the benzodiazepine meclonazepam (MCLZ). However, host side effects caused by benzodiazepines preclude development of MCLZ as a drug and MCLZ lacks an identified parasite target to catalyze rational drug design for engineering out human host activity. Here, we identify a transient receptor potential ion channel of the melastatin subfamily, named TRPMMCLZ, as a parasite target of MCLZ. MCLZ potently activates Schistosoma mansoni TRPMMCLZ through engagement of a binding pocket within the voltage-sensor-like domain of the ion channel to cause worm paralysis, tissue depolarization, and surface damage. TRPMMCLZ reproduces all known features of MCLZ action on schistosomes, including a lower activity versus Schistosoma japonicum, which is explained by a polymorphism within this voltage-sensor-like domain-binding pocket. TRPMMCLZ is distinct from the TRP channel targeted by PZQ (TRPMPZQ), with both anthelmintic chemotypes targeting unique parasite TRPM paralogs. This advances TRPMMCLZ as a novel druggable target that could circumvent any target-based resistance emerging in response to current mass drug administration campaigns centered on PZQ.


Assuntos
Anti-Helmínticos , Clonazepam , Esquistossomose mansoni , Canais de Cátion TRPM , Animais , Humanos , Anti-Helmínticos/farmacologia , Benzodiazepinas/farmacologia , Benzodiazepinonas/farmacologia , Clonazepam/análogos & derivados , Clonazepam/farmacologia , Praziquantel/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/metabolismo , Esquistossomose mansoni/tratamento farmacológico , Canais de Cátion TRPM/agonistas
3.
FASEB J ; 38(16): e70015, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39212294

RESUMO

Pulmonary hypertension (PH) is a chronic and progressive disease with significant morbidity and mortality. It is characterized by remodeled pulmonary vessels associated with perivascular and intravascular accumulation of inflammatory cells. Although there is compelling evidence that bone marrow-derived cells, such as macrophages and T cells, cluster in the vicinity of pulmonary vascular lesions in humans and contribute to PH development in different animal models, the role of dendritic cells in PH is less clear. Dendritic cells' involvement in PH is likely since they are responsible for coordinating innate and adaptive immune responses. We hypothesized that dendritic cells drive hypoxic PH. We demonstrate that a classical dendritic cell (cDC) subset (cDC2) is increased and activated in wild-type mouse lungs after hypoxia exposure. We observe significant protection after the depletion of cDCs in ZBTB46 DTR chimera mice before hypoxia exposure and after established hypoxic PH. In addition, we find that cDC depletion is associated with a reduced number of two macrophage subsets in the lung (FolR2+ MHCII+ CCR2+ and FolR2+ MHCII+ CCR2-). We found that depleting cDC2s, but not cDC1s, was protective against hypoxic PH. Finally, proof-of-concept studies in human lungs show increased perivascular cDC2s in patients with Idiopathic Pulmonary Arterial Hypertension (IPAH). Our data points to an essential role of cDCs, particularly cDC2s, in the pathophysiology of experimental PH.


Assuntos
Células Dendríticas , Hipertensão Pulmonar , Hipóxia , Camundongos Endogâmicos C57BL , Animais , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/patologia , Células Dendríticas/imunologia , Camundongos , Humanos , Masculino , Pulmão/patologia , Pulmão/metabolismo , Pulmão/imunologia , Macrófagos/metabolismo , Macrófagos/imunologia , Feminino
4.
Am J Respir Crit Care Med ; 210(3): 329-342, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568479

RESUMO

Rationale: Idiopathic pulmonary arterial hypertension (IPAH) is characterized by extensive pulmonary vascular remodeling caused by plexiform and obliterative lesions, media hypertrophy, inflammatory cell infiltration, and alterations of the adventitia. Objective: We sought to test the hypothesis that microscopic IPAH vascular lesions express unique molecular profiles, which collectively are different from control pulmonary arteries. Methods: We used digital spatial transcriptomics to profile the genomewide differential transcriptomic signature of key pathological lesions (plexiform, obliterative, intima+media hypertrophy, and adventitia) in IPAH lungs (n = 11) and compared these data with the intima+media hypertrophy and adventitia of control pulmonary artery (n = 5). Measurements and Main Results: We detected 8,273 transcripts in the IPAH lesions and control lung pulmonary arteries. Plexiform lesions and IPAH adventitia exhibited the greatest number of differentially expressed genes when compared with intima+media hypertrophy and obliterative lesions. Plexiform lesions in IPAH showed enrichment for 1) genes associated with transforming growth factor ß signaling and 2) mutated genes affecting the extracellular matrix and endothelial-mesenchymal transformation. Plexiform lesions and IPAH adventitia showed upregulation of genes involved in immune and IFN signaling, coagulation, and complement pathways. Cellular deconvolution indicated variability in the number of vascular and inflammatory cells between IPAH lesions, which underlies the differential transcript profiling. Conclusions: IPAH lesions express unique molecular transcript profiles enriched for pathways involving pathogenetic pathways, including genetic disease drivers, innate and acquired immunity, hypoxia sensing, and angiogenesis signaling. These data provide a rich molecular-structural framework in IPAH vascular lesions that inform novel biomarkers and therapeutic targets in this highly morbid disease.


Assuntos
Artéria Pulmonar , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Artéria Pulmonar/patologia , Remodelação Vascular/genética , Perfilação da Expressão Gênica/métodos , Hipertensão Arterial Pulmonar/genética , Transcriptoma/genética , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/fisiopatologia
5.
Drug Resist Updat ; 77: 101146, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39243602

RESUMO

Despite the ongoing advances in interventional strategies (surgery, chemotherapy, radiotherapy, and immunotherapy) for managing pancreatic ductal adenocarcinoma (PDAC), the development of therapy refractory phenotypes remains a significant challenge. Resistance to various therapeutic modalities in PDAC emanates from a combination of inherent and acquired factors and is attributable to cancer cell-intrinsic and -extrinsic mechanisms. The critical determinants of therapy resistance include oncogenic signaling and epigenetic modifications that drive cancer cell stemness and metabolic adaptations, CAF-mediated stromagenesis that results in ECM deposition altered mechanotransduction, and secretome and immune evasion. We reviewed the current understanding of these multifaceted mechanisms operating in the PDAC microenvironment, influencing the response to chemotherapy, radiotherapy, and immunotherapy regimens. We then describe how the lessons learned from these studies can guide us to discover novel therapeutic regimens to prevent, delay, or revert resistance and achieve durable clinical responses.

6.
J Biol Chem ; 299(12): 105378, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866635

RESUMO

Membrane contact sites (MCSs) between endosomes and the endoplasmic reticulum (ER) are thought to act as specialized trigger zones for Ca2+ signaling, where local Ca2+ released via endolysosomal ion channels is amplified by ER Ca2+-sensitive Ca2+ channels into global Ca2+ signals. Such amplification is integral to the action of the second messenger, nicotinic acid adenine dinucleotide phosphate (NAADP). However, functional regulators of inter-organellar Ca2+ crosstalk between endosomes and the ER remain poorly defined. Here, we identify progesterone receptor membrane component 1 (PGRMC1), an ER transmembrane protein that undergoes a unique heme-dependent dimerization, as an interactor of the endosomal two pore channel, TPC1. NAADP-dependent Ca2+ signals were potentiated by PGRMC1 overexpression through enhanced functional coupling between endosomal and ER Ca2+ stores and inhibited upon PGRMC1 knockdown. Point mutants in PGMRC1 or pharmacological manipulations that reduced its interaction with TPC1 were without effect. PGRMC1 therefore serves as a TPC1 interactor that regulates ER-endosomal coupling with functional implications for cellular Ca2+ dynamics and potentially the distribution of heme.


Assuntos
Sinalização do Cálcio , Retículo Endoplasmático , Endossomos , Receptores de Progesterona , Humanos , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Heme/metabolismo , Lisossomos/metabolismo , NADP/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo
7.
Small ; 20(27): e2308796, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38363026

RESUMO

A race to achieve a crossover from positive to negative magnetoresistance is intense in the field of nanostructured materials to reduce the size of memory devices. Here, the unusual complex magnetoresistance in nonmagnetic sulfur-doped Sb2Se3 nanowires is demonstrated. Intentionally, sulfur is doped in such a way to nearly achieve the charge neutrality point that is evident from switching of carrier type from p-type to n-type at 13 K as inferred from the low-temperature thermoelectric power measurements. A change from 3D variable range hopping (VRH) to power law transport with α = 0.18  in resistivity measurement signifies a Luttinger liquid transport with weak links through the nanowires. Interestingly, high magnetic field induced negative magnetoresistance (NMR) occurring in hole dominated temperature regimes can only be explained by invoking the concept of charge puddles. Spot energy dispersive spectroscopy (EDS), magnetic force microscopy (MFM) measurements, Tmott and Regel plot indicate an enhanced disorder in these sulfurized nanowires that are found to be the precursor for the formation of these charge puddles. Tunability of conducting states in these nanowires is investigated in the light of interplay of carrier type, magnetic field, temperature, and intricate intra-inter wire transport that makes this nanowires potential for large scale spintronic devices.

8.
Int J Obes (Lond) ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937647

RESUMO

BACKGROUND/OBJECTIVES: Intrauterine metabolic reprogramming occurs in mothers with obesity during gestation, putting the offspring at high risk of developing obesity and associated metabolic disorders even before birth. We have generated a mouse model of maternal high-fat diet-induced obesity that recapitulates the metabolic changes seen in humans born to women with obesity. METHODS: Here, we profiled and compared the metabolic characteristics of bone marrow cells of newly weaned 3-week-old offspring of dams fed either a high-fat (Off-HFD) or a regular diet (Off-RD). We utilized a state-of-the-art flow cytometry, and targeted metabolomics approach coupled with a Seahorse metabolic analyzer. RESULTS: We revealed significant metabolic perturbation in the offspring of HFD-fed vs. RD-fed dams, including utilization of glucose primarily via oxidative phosphorylation. We also show a reduction in levels of amino acids, a phenomenon previously linked to bone marrow aging. Using flow cytometry, we found changes in the immune complexity of bone marrow cells and identified a unique B cell population expressing CD19 and CD11b in the bone marrow of three-week-old offspring of high-fat diet-fed mothers. Our data also revealed increased expression of Cyclooxygenase-2 (COX-2) on myeloid CD11b, and on CD11bhi B cells. CONCLUSIONS: Altogether, we demonstrate that the offspring of mothers with obesity show metabolic and immune changes in the bone marrow at a very young age and prior to any symptomatic metabolic disease.

9.
Semin Immunol ; 47: 101391, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31952903

RESUMO

Pancreatic cancer (PC) is a highly lethal malignancy with a dismal five-year survival rate. This is due to its asymptomatic nature, lack of reliable biomarkers, poor resectability, early metastasis, and high recurrence rate. Limited efficacies of current treatment modalities treatment-associated toxicity underscore the need for the development of immunotherapy-based approaches. For non-resectable, locally advanced metastatic PC, immunotherapy-based approaches including vaccines, antibody-targeted, immune checkpoint inhibition, CAR-T-cells, and adoptive T-cell transfer could be valuable additions to existing treatment modalities. Thus far, the vaccine candidates in PC have demonstrated modest immunological responses in different treatment modalities. The identification of tumor-associated antigens (TAA) and their successful implication in PC treatment is still a challenge. MUC4, a high molecular weight glycoprotein that functionally contributes to PC pathogenesis, is an attractive TAA. It is not detected in the normal pancreas; however, it is overexpressed in mouse and human pancreatic tumors. The recombinant MUC4 domain, as well as predicted immunogenic T-cell epitopes, elicited cellular and humoral anti-MUC4 response, suggesting its ulility as a vaccine candidate for PC therapy. Existence of PC-associated MUC4 splice variants, autoantibodies against overexpressed and aberrantly glycosylated MUC4 and presence of T-cell clones against the mutations present in MUC4 further reinforce its significance as a tumor antigen for vaccine development. Herein, we review the significance of MUC4 as a tumor antigen in PC immunotherapy and discuss both, the development and challenges associated with MUC4 based immunotherapy. Lastly, we will present our perspective on MUC4 antigenicity for the future development of MUC4-based PC immunotherapy.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoterapia , Mucina-4/imunologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Animais , Antígenos de Neoplasias/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Biologia Computacional/métodos , Epitopos , Humanos , Imunoterapia/efeitos adversos , Imunoterapia/métodos , Mucina-4/antagonistas & inibidores , Mucina-4/genética , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
10.
Environ Monit Assess ; 196(6): 548, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743314

RESUMO

Palaeochannels are remnants of rivers or stream channels filled with younger sediments over the period of time. In ancient times, these rivers/channels were thriving in phenomenal conditions, but due to frequent tectonic activities, they lost the direction of their original path and were gradually either lost or buried under thick beds of younger alluvium. Palaeochannels act as reservoirs for fresh groundwater since they are made up of coarser sediments and were formerly flowing rivers. Depending on the groundwater regime and local topography, these could either be saturated or dry. The palaeochannels have high groundwater potential if saturated. These are ideal sites for artificial groundwater recharge, if dry. The identification of palaeochannels becomes quite challenging if they are buried under thick deposits of finer younger sediments. In the present study, an attempt has been made to characterize the Saraswati River Palaeochannel in parts of Yamuna Nagar and Kurukshetra districts of Haryana by using surface and subsurface geophysical methods. Till date, the palaeochannels in this area were mainly discerned on the basis of remote sensing only; therefore, geophysical characterization of these palaeochannels has been attempted in this study. In surface geophysical methods, electrical resistivity surveys, especially gradient resistivity profiling (GRP) and vertical electrical sounding (VES), were conducted in the study area, while electrical and natural gamma logging was used as subsurface geophysical approaches to identify the coarser sands of buried palaeochannels. The main objective of the study was to characterize the Saraswati River palaeochannel and analyze the quality of the groundwater stored in the palaeochannel in the study area. The findings were compared with the well-log data and were found in good agreement.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Água Subterrânea , Rios , Rios/química , Índia , Água Subterrânea/química , Sedimentos Geológicos/química
11.
Environ Monit Assess ; 196(2): 165, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233613

RESUMO

Air pollution is one of the most significant threats to human safety due to its detrimental health consequences worldwide. This study examines the air pollution levels in 22 districts of West Bengal from 2016 to 2021, using data from 81 stations operated by the West Bengal Pollution Control Board (WBPCB). The study assesses the short- and long-term impacts of particulate matter (PM) on human health. The highest annual variation of PM10 was noted in 2016 (106.99 ± 34.17 µg/m3), and the lowest was reported in 2020 (88.02 ± 13.61 µg/m3), whereas the highest annual variations of NO2 (µg/m3) were found in 2016 (35.17 ± 13.55 µg/m3), and lowest in 2019 (29.72 ± 13.08 µg/m3). Similarly, the SO2 level was lower (5.35 µg/m3) in 2017 and higher in 2020 (7.78 µg/m3). In the state, Bardhaman, Bankura, Kolkata, and Howrah recorded the highest PM10 concentrations. The monthly and seasonal variations of pollution showed higher in December, January, and February (winter season) and lowest observed in June, July, and August (rainy season). The southern part of West Bengal state has recorded higher pollution levels than the northern part. The short- and long-term health impact assessment due to particulate matter shows that the estimated number of attributable cases (ENACs) for incidence of chronic bronchitis in adults and prevalence of bronchitis in children were 305,234 and 14,652 respectively. The long-term impact of PM2.5 on human health ENACs for mortality due to chronic obstructive pulmonary disease for adults, acute lower respiratory infections in children aged 0-5, lung cancer, and stroke for adults were 21,303, 12,477, 25,064, 94,406, and 86,272 respectively. This outcome assists decision-makers and stakeholders in effectively addressing the air pollution and health risk concerns within the specified area.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Criança , Adulto , Humanos , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Poluição do Ar/análise , Material Particulado/análise , Índia/epidemiologia , Exposição Ambiental
12.
Med J Armed Forces India ; 80(1): 46-51, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38261873

RESUMO

Background: Phlebitis is one of the most common complications of the peripheral venous catheter (PVC) and adversely impacts future venous access, and bacterial phlebitis may lead to bloodstream infection. The objective of the study was to reduce the to reduce the incidence of infusion-related phlebitis in children admitted to the pediatric critical care unit. Methods: This Quality Initiative was implemented in the pediatric critical care unit of a tertiary care hospital between November 2019 and April 2020. Five interventions were identified (hand hygiene, use of transparent dressing, use of extension lines with PVCs, use of hard cardboard splints for joint immobilization, use of heparinized flush after medication administration) and were introduced sequentially. Over the next five weeks, a new intervention was introduced weekly while continuing the previous ones, if found to be working well as per improvement parameter, the phlebitis rate. From the sixth week onwards, all five interventions were applied together as a bundle. Results: Total seven hundred eighteen PVCs were sited in 284 (Male: female 1.58:1) patients during study period and a total of 56 incidences of phlebitis were observed. Mean baseline phlebitis rate was 48.5%. In the next 5 weeks when interventions were implemented as planned, phlebitis rate was 35.7% (n = 10), 16.6% (n = 03), 21.6% (n = 8), 10% (n = 05), and 13.3% (n = 2) respectively. Implementation of all five interventions together as a bundle led to reduction in phlebitis rate below 5 % consistently over the next 18 weeks (n = 8). Conclusion: A consistent reduction in PVC-related phlebitis can be achieved by the implementation of evidence-based interventions for the prevention of phlebitis, as a bundle.

13.
Semin Cancer Biol ; 86(Pt 3): 1216-1230, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36330953

RESUMO

Cancer cells undergo metabolic alterations to meet the immense demand for energy, building blocks, and redox potential. Tumors show glucose-avid and lactate-secreting behavior even in the presence of oxygen, a process known as aerobic glycolysis. Glycolysis is the backbone of cancer cell metabolism, and cancer cells have evolved various mechanisms to enhance it. Glucose metabolism is intertwined with other metabolic pathways, making cancer metabolism diverse and heterogeneous, where glycolysis plays a central role. Oncogenic signaling accelerates the metabolic activities of glycolytic enzymes, mainly by enhancing their expression or by post-translational modifications. Aerobic glycolysis ferments glucose into lactate which supports tumor growth and metastasis by various mechanisms. Herein, we focused on tumor glycolysis, especially its interactions with the pentose phosphate pathway, glutamine metabolism, one-carbon metabolism, and mitochondrial oxidation. Further, we describe the role and regulation of key glycolytic enzymes in cancer. We summarize the role of lactate, an end product of glycolysis, in tumor growth, and the metabolic adaptations during metastasis. Lastly, we briefly discuss limitations and future directions to improve our understanding of glucose metabolism in cancer.


Assuntos
Glicólise , Neoplasias , Humanos , Ciclo do Ácido Cítrico , Ácido Láctico , Glucose
14.
Semin Cancer Biol ; 86(Pt 2): 499-510, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35346801

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) tumor microenvironment (TME) consists of multiple cell types interspersed by dense fibrous stroma. These cells communicate through low molecular weight signaling molecules called cytokines. The cytokines, through their receptors, facilitate PDAC initiation, progression, metastasis, and distant colonization of malignant cells. These signaling mediators secreted from tumor-associated macrophages, and cancer-associated fibroblasts in conjunction with oncogenic Kras mutation initiate acinar to ductal metaplasia (ADM), resulting in the appearance of early preneoplastic lesions. Further, M1- and M2-polarized macrophages provide proinflammatory conditions and promote deposition of extracellular matrix, whereas myofibroblasts and T-lymphocytes, such as Th17 and T-regulatory cells, create a fibroinflammatory and immunosuppressive environment with a significantly reduced cytotoxic T-cell population. During PDAC progression, cytokines regulate the expression of various oncogenic regulators such as NFκB, c-myc, growth factor receptors, and mucins resulting in the formation of high-grade PanIN lesions, epithelial to mesenchymal transition, invasion, and extravasation of malignant cells, and metastasis. During metastasis, PDAC cells colonize at the premetastatic niche created in the liver, and lung, an organotropic function primarily executed by cytokines in circulation or loaded in the exosomes from the primary tumor cells. The indispensable contribution of these cytokines at every stage of PDAC tumorigenesis makes them exciting candidates in combination with immune-, chemo- and targeted radiation therapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Microambiente Tumoral , Citocinas , Transição Epitelial-Mesenquimal/genética , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Carcinogênese/genética , Neoplasias Pancreáticas
15.
Semin Cancer Biol ; 86(Pt 2): 511-520, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35346803

RESUMO

Pancreatic cancer (PC) is exemplified by a complex immune-suppressive, fibrotic tumor microenvironment (TME), and aberrant expression of mucins. The constant crosstalk between cancer cells, cancer-associated fibroblasts (CAFs), and the immune cells mediated by the soluble factors and inflammatory mediators including cytokines, chemokines, reactive oxygen species (ROS) promote the dynamic temporal switch towards an immune-escape phenotype in the neoplastic cells and its microenvironment that bolsters disease progression. Chemokines have been studied in PC pathogenesis, albeit poorly in the context of mucins, tumor glycocalyx, and TME heterogeneity (CAFs and immune cells). With correlative analysis from PC patients' transcriptome data, support from available literature, and scientific arguments-based speculative extrapolations in terms of disease pathogenesis, we have summarized in this review a comprehensive understanding of chemokine-mucinome interplay during stromal modulation and immune-suppression in PC. Future studies should focus on deciphering the complexities of chemokine-mediated control of glycocalyx maturation, immune infiltration, and CAF-associated immune suppression. Knowledge extracted from such studies will be beneficial to mechanistically correlate the mucin-chemokine abundance in serum versus pancreatic tumors of patients, which may aid in prognostication and stratification of PC patients for immunotherapy.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Humanos , Microambiente Tumoral , Fibroblastos Associados a Câncer/metabolismo , Neoplasias Pancreáticas/patologia , Quimiocinas/metabolismo , Mucinas/metabolismo , Neoplasias Pancreáticas
16.
Semin Cancer Biol ; 86(Pt 2): 14-27, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36041672

RESUMO

Pancreatic cancer (PC) has exceptionally high mortality due to ineffective treatment strategies. Immunotherapy, which mobilizes the immune system to fight against cancer, has been proven successful in multiple cancers; however, its application in PC has met with limited success. In this review, we articulated that the pancreatic tumor microenvironment is immuno-suppressive with extensive infiltration by M2-macrophages and myeloid-derived suppressive cells but low numbers of cytotoxic T-cells. In addition, low mutational load and poor antigen processing, presentation, and recognition contribute to the limited response to immunotherapy in PC. Immune checkpoints, the critical targets for immunotherapy, have high expression in PC and stromal cells, regulated by tumor microenvironmental milieu (cytokine and metabolites) and cell-intrinsic mechanisms (epigenetic regulation, oncogenic signaling, and post-translational modifications). Combining immunotherapy with modulators of the tumor microenvironment may facilitate the development of novel therapeutic regimens to manage PC.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias Pancreáticas , Humanos , Epigênese Genética , Neoplasias Pancreáticas/patologia , Imunoterapia , Microambiente Tumoral , Neoplasias Pancreáticas
17.
Am J Respir Cell Mol Biol ; 69(5): 570-583, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37343939

RESUMO

Pulmonary hypertension (PH) is a heterogeneous and life-threatening cardiopulmonary disorder in which mitochondrial dysfunction is believed to drive pathogenesis, although the underlying mechanisms remain unclear. To determine if abnormal SIRT3 (sirtuin 3) activity is related to mitochondrial dysfunction in adventitial fibroblasts from patients with idiopathic pulmonary arterial hypertension (IPAH) and hypoxic PH calves (PH-Fibs) and whether SIRT3 could be a potential therapeutic target to improve mitochondrial function, SIRT3 concentrations in control fibroblasts, PH-Fibs, and lung tissues were determined using quantitative real-time PCR and western blot. SIRT3 deacetylase activity in cells and lung tissues was determined using western blot, immunohistochemistry staining, and immunoprecipitation. Glycolysis and mitochondrial function in fibroblasts were measured using respiratory analysis and fluorescence-lifetime imaging microscopy. The effects of restoring SIRT3 activity (by overexpression of SIRT3 with plasmid, activation SIRT3 with honokiol, and supplementation with the SIRT3 cofactor nicotinamide adenine dinucleotide [NAD+]) on mitochondrial protein acetylation, mitochondrial function, cell proliferation, and gene expression in PH-Fibs were also investigated. We found that SIRT3 concentrations were decreased in PH-Fibs and PH lung tissues, and its cofactor, NAD+, was also decreased in PH-Fibs. Increased acetylation in overall mitochondrial proteins and SIRT3-specific targets (MPC1 [mitochondrial pyruvate carrier 1] and MnSOD2 [mitochondrial superoxide dismutase]), as well as decreased MnSOD2 activity, was identified in PH-Fibs and PH lung tissues. Normalization of SIRT3 activity, by increasing its expression with plasmid or with honokiol and supplementation with its cofactor NAD+, reduced mitochondrial protein acetylation, improved mitochondrial function, inhibited proliferation, and induced apoptosis in PH-Fibs. Thus, our study demonstrated that restoration of SIRT3 activity in PH-Fibs can reduce mitochondrial protein acetylation and restore mitochondrial function and PH-Fib phenotype in PH.


Assuntos
Hipertensão Pulmonar , Sirtuína 3 , Humanos , Animais , Bovinos , Hipertensão Pulmonar/patologia , Sirtuína 3/genética , Sirtuína 3/metabolismo , NAD/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Fibroblastos/metabolismo
18.
Am J Respir Cell Mol Biol ; 69(2): 210-219, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37071849

RESUMO

Endothelial dysfunction and inflammation contribute to the vascular pathology of coronavirus disease (COVID-19). However, emerging evidence does not support direct infection of endothelial or other vascular wall cells, and thus inflammation may be better explained as a secondary response to epithelial cell infection. In this study, we sought to determine whether lung endothelial or other resident vascular cells are susceptible to productive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and how local complement activation contributes to endothelial dysfunction and inflammation in response to hypoxia and SARS-CoV-2-infected lung alveolar epithelial cells. We found that ACE2 (angiotensin-converting enzyme 2) and TMPRSS2 (transmembrane serine protease 2) mRNA expression in lung vascular cells, including primary human lung microvascular endothelial cells (HLMVECs), pericytes, smooth muscle cells, and fibroblasts, was 20- to 90-fold lower compared with primary human alveolar epithelial type II cells. Consistently, we found that HLMVECs and other resident vascular cells were not susceptible to productive SARS-CoV-2 infection under either normoxic or hypoxic conditions. However, viral uptake without replication (abortive infection) was observed in HLMVECs when exposed to conditioned medium from SARS-CoV-2-infected human ACE2 stably transfected A549 epithelial cells. Furthermore, we demonstrated that exposure of HLMVECs to conditioned medium from SARS-CoV-2-infected human ACE2 stably transfected A549 epithelial cells and hypoxia resulted in upregulation of inflammatory factors such as ICAM-1 (intercellular adhesion molecule 1), VCAM-1 (vascular cell adhesion molecule 1), and IL-6 (interleukin 6) as well as complement components such as C3 (complement C3), C3AR1 (complement C3a receptor 1), C1QA (complement C1q A chain), and CFB (complement factor B). Taken together, our data support a model in which lung endothelial and vascular dysfunction during COVID-19 involves the activation of complement and inflammatory signaling and does not involve productive viral infection of endothelial cells.


Assuntos
COVID-19 , Humanos , COVID-19/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , SARS-CoV-2/metabolismo , Células Endoteliais/metabolismo , Meios de Cultivo Condicionados , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pulmão/patologia , Inflamação/metabolismo , Proteínas do Sistema Complemento/metabolismo
19.
BMC Genomics ; 24(1): 349, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365517

RESUMO

T cell receptor repertoires can be profiled using next generation sequencing (NGS) to measure and monitor adaptive dynamical changes in response to disease and other perturbations. Genomic DNA-based bulk sequencing is cost-effective but necessitates multiplex target amplification using multiple primer pairs with highly variable amplification efficiencies. Here, we utilize an equimolar primer mixture and propose a single statistical normalization step that efficiently corrects for amplification bias post sequencing. Using samples analyzed by both our open protocol and a commercial solution, we show high concordance between bulk clonality metrics. This approach is an inexpensive and open-source alternative to commercial solutions.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Linfócitos T , Sequência de Bases , Mapeamento Cromossômico , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Receptores de Antígenos de Linfócitos T alfa-beta/genética
20.
J Cell Biochem ; 124(1): 127-145, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502494

RESUMO

Numerous pathogens affecting human is present in the flavivirus family namely west nile, dengue, yellow fever, and zika which involves in development of global burden and distressing the environment economically. Till date, no approved drugs are available for targeting these viruses. The threat which urged the identification of small molecules for the inhibition of these viruses is the spreading of serious viral diseases. The recent outbreak of zika and dengue infections postured a solemn risk to worldwide public well-being. RNA-dependent RNA polymerase (RdRp) is the supreme adaptable enzymes of all the RNA viruses which is responsible for the replication and transcription of genome among the structural and nonstructural proteins of flaviviruses. It is understood that the RdRp of the flaviviruses are similar stating that the japanese encephalitis and west nile shares 70% identity with zika whereas the dengue serotype 2 and 3 shares the identity of 76% and 81%, respectively. In this study, we investigated the binding site of four flaviviral RdRp and provided insights into various interaction of the molecules using the computational approach. Our study helps in recognizing the potent compounds that could inhibit the viral protein as a common inhibitor. Additionally, with the conformational stability analysis, we proposed the possible mechanism of inhibition of the identified common small molecule toward RdRp of flavivirus. Finally, this study could be an initiative for the identification of common inhibitors and can be explored further for understanding the mechanism of action through in vitro studies for the study on efficacy.


Assuntos
Reposicionamento de Medicamentos , Flavivirus , RNA Polimerase Dependente de RNA , Humanos , Dengue/tratamento farmacológico , Flavivirus/efeitos dos fármacos , Flavivirus/enzimologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo , Zika virus/efeitos dos fármacos , Zika virus/enzimologia , Infecção por Zika virus/tratamento farmacológico
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