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1.
Adv Mater ; : e2310351, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591658

RESUMO

Obesity is a significant health concern that often leads to metabolic dysfunction and chronic diseases. This study introduces a novel approach to combat obesity using orally ingested self-powered electrostimulators. These electrostimulators consist of piezoelectric BaTiO3 (BTO) particles conjugated with capsaicin (Cap) and aim to activate the vagus nerve. Upon ingestion by diet-induced obese (DIO) mice, the BTO@Cap particles specifically target and bind to Cap-sensitive sensory nerve endings in the gastric mucosa. In response to stomach peristalsis, these particles generate electrical signals. The signals travel via the gut-brain axis, ultimately influencing the hypothalamus. By enhancing satiety signals in the brain, this neuromodulatory intervention reduces food intake, promotes energy metabolism, and demonstrates minimal toxicity. Over a 3-week period of daily treatments, DIO mice treated with BTO@Cap particles show a significant reduction in body weight compared to control mice, while maintaining their general locomotor activity. Furthermore, this BTO@Cap particle-based treatment mitigates various metabolic alterations associated with obesity. Importantly, this noninvasive and easy-to-administer intervention holds potential for addressing other intracerebral neurological diseases.

2.
Surg Neurol Int ; 15: 105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628539

RESUMO

Background: Various clinical symptoms and variables have been suggested as potential indicators of outcomes in patients with subarachnoid hemorrhage (SAH) resulting from ruptured intracranial aneurysms. The detailed discussion of the consequences of intraventricular hemorrhage (IVH), frequently reported in cases of anterior communicating artery (ACoA) aneurysms, is still pending. The study aimed to assess the results of aneurysm surgery performed early versus delayed in patients with SAH, specifically focusing on the occurrence of IVH. Methods: This study involved patients with ACoA aneurysms who experienced SAH and underwent microsurgical clipping of the aneurysm. A retrospective review was conducted on the patients' medical records. The modified Rankin score was compared between two groups of patients based on the presence or absence of IVH. Results: Ninety-one participants (52 males and 39 females) were included in the study. The initial computed tomography scan showed that 20 patients (with a mean age of 51 ± 13.7 years) had IVH, while 71 patients (with a mean age of 45.8 ± 11.7 years) did not have any signs of IVH. The proportion of patients with poor functional outcomes after six months was 55% in the presence of IVH, compared to 25.4% in patients without IVH, indicating a significant difference in outcome between the two groups (P < 0.016). Conclusion: Patients with SAH having aneurysms located in the ACoA associated with the intraventricular hemorrhage had a poor functional outcome.

3.
Am J Trop Med Hyg ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38574550

RESUMO

Surveillance for genetic markers of resistance can provide valuable information on the likely efficacy of antimalarials but needs to be targeted to ensure optimal use of resources. We conducted a systematic search and review of publications in seven databases to compile resistance marker data from studies in India. The sample collection from the studies identified from this search was conducted between 1994 and 2020, and these studies were published between 1994 and 2022. In all, Plasmodium falciparum Kelch13 (PfK13), P. falciparum dihydropteroate synthase, and P. falciparum dihydrofolate reductase (PfDHPS) genotype data from 2,953, 4,148, and 4,222 blood samples from patients with laboratory-confirmed malaria, respectively, were extracted from these publications and uploaded onto the WorldWide Antimalarial Resistance Network molecular surveyors. These data were fed into hierarchical geostatistical models to produce maps with a predicted prevalence of the PfK13 and PfDHPS markers, and of the associated uncertainty. Zones with a predicted PfDHPS 540E prevalence of >15% were identified in central, eastern, and northeastern India. The predicted prevalence of PfK13 mutants was nonzero at only a few locations, but were within or adjacent to the zones with >15% prevalence of PfDHPS 540E. There may be a greater probability of artesunate-sulfadoxine-pyrimethamine failures in these regions, but these predictions need confirmation. This work can be applied in India and elsewhere to help identify the treatments most likely to be effective for malaria elimination.

4.
Front Immunol ; 15: 1268652, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558822

RESUMO

Introduction: A multitude of findings from cell cultures and animal studies are available to support the anti-cancer properties of cannabidiol (CBD). Since CBD acts on multiple molecular targets, its clinical adaptation, especially in combination with cancer immunotherapy regimen remains a serious concern. Methods: Considering this, we extensively studied the effect of CBD on the cytokine-induced killer (CIK) cell immunotherapy approach using multiple non-small cell lung cancer (NSCLC) cells harboring diverse genotypes. Results: Our analysis showed that, a) The Transient Receptor Potential Cation Channel Subfamily V Member 2 (TRPV2) channel was intracellularly expressed both in NSCLC cells and CIK cells. b) A synergistic effect of CIK combined with CBD, resulted in a significant increase in tumor lysis and Interferon gamma (IFN-g) production. c) CBD had a preference to elevate the CD25+CD69+ population and the CD62L_CD45RA+terminal effector memory (EMRA) population in NKT-CIK cells, suggesting early-stage activation and effector memory differentiation in CD3+CD56+ CIK cells. Of interest, we observed that CBD enhanced the calcium influx, which was mediated by the TRPV2 channel and elevated phosphor-Extracellular signal-Regulated Kinase (p-ERK) expression directly in CIK cells, whereas ERK selective inhibitor FR180204 inhibited the increasing cytotoxic CIK ability induced by CBD. Further examinations revealed that CBD induced DNA double-strand breaks via upregulation of histone H2AX phosphorylation in NSCLC cells and the migration and invasion ability of NSCLC cells suppressed by CBD were rescued using the TRPV2 antagonist (Tranilast) in the absence of CIK cells. We further investigated the epigenetic effects of this synergy and found that adding CBD to CIK cells decreased the Long Interspersed Nuclear Element-1 (LINE-1) mRNA expression and the global DNA methylation level in NSCLC cells carrying KRAS mutation. We further investigated the epigenetic effects of this synergy and found that adding CBD to CIK cells decreased the Long Interspersed Nuclear Element-1 (LINE-1) mRNA expression and the global DNA methylation level in NSCLC cells carrying KRAS mutation. Conclusions: Taken together, CBD holds a great potential for treating NSCLC with CIK cell immunotherapy. In addition, we utilized NSCLC with different driver mutations to investigate the efficacy of CBD. Our findings might provide evidence for CBD-personized treatment with NSCLC patients.


Assuntos
Canabidiol , Carcinoma Pulmonar de Células não Pequenas , Células Matadoras Induzidas por Citocinas , Neoplasias Pulmonares , Animais , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Canabidiol/farmacologia , Neoplasias Pulmonares/terapia , Proteínas Proto-Oncogênicas p21(ras) , RNA Mensageiro
5.
Am J Trop Med Hyg ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38579702

RESUMO

Malaria elimination is one of the top health care priorities in India, necessitating accessible and accurate diagnosis for effective treatment. A malaria slide bank in India is a collection of quality-controlled malaria-positive and -negative slides and is considered a vital asset for quality diagnosis. The collection of blood samples, preparation of blood smears, staining, quality control, molecular characterizations, and slide validation were carried out according to standard operating procedures in accordance with the WHO reference laboratory. The true count and parasite density per microliter were computed in accordance with WHO guidelines. Over 27 months, 48 batches (8,196 slides) were prepared. Overall, the majority of slide batches were Plasmodium vivax (45.9%; 22/48), followed by Plasmodium falciparum (25%; 12/48), malaria-negative infections (25%; 12/48), and mixed infections (4.1%; 2/48). All 48 batches passed internal validation by WHO-certified level-1 microscopists. For a batch, the true count was the median of the validators' counts (range, 111-280,795 parasites/µL). Except for mixed infections, the PCR results agreed with the verified microscopy results. Malaria slide bank slides would be a valuable tool for quality control, assurance, and microscopist training.

6.
Int J Med Robot ; 20(2): e2631, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38642395

RESUMO

BACKGROUND: Liver parenchymal transection during robotic liver resection (RLR) remains a significant challenge due to the limited range of specialised instruments. This study introduces our 'Burn and Push' technique as a novel approach to address these challenges. METHODS: A retrospective analysis was conducted on 20 patients who underwent RLR using the 'Burn and Push' technique at Virginia Commonwealth University Health System from November 2021 to August 2023. The study evaluated peri- and post-operative outcomes. RESULTS: The median operation time was 241.5 min (range, 90-620 min), and the median blood loss was 100 mL (range, 10-600 mL). Major complications occurred in one case, with no instances of postoperative bleeding, bile leak, or liver failure. CONCLUSIONS: The 'Burn and Push' technique is a viable and efficient alternative for liver parenchymal transection in RLR. Further research with larger sample sizes and consideration of the learning curve is necessary to validate these findings.


Assuntos
Queimaduras , Laparoscopia , Neoplasias Hepáticas , Procedimentos Cirúrgicos Robóticos , Humanos , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Fígado/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Queimaduras/cirurgia
7.
Malar J ; 23(1): 107, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632650

RESUMO

BACKGROUND: Achieving effective control and elimination of malaria in endemic regions necessitates a comprehensive understanding of local mosquito species responsible for malaria transmission and their susceptibility to insecticides. METHODS: The study was conducted in the highly malaria prone Ujina Primary Health Center of Nuh (Mewat) district of Haryana state of India. Monthly entomological surveys were carried out for adult mosquito collections via indoor resting collections, light trap collections, and pyrethrum spray collections. Larvae were also collected from different breeding sites prevalent in the region. Insecticide resistance bioassay, vector incrimination, blood meal analysis was done with the collected vector mosquitoes. RESULTS: A total of 34,974 adult Anopheles mosquitoes were caught during the survey period, out of which Anopheles subpictus was predominant (54.7%). Among vectors, Anopheles stephensi was predominant (15.5%) followed by Anopheles culicifacies (10.1%). The Human Blood Index (HBI) in the case of An. culicifacies and An. stephensi was 6.66 and 9.09, respectively. Vector incrimination results revealed Plasmodium vivax positivity rate of 1.6% for An. culicifacies. Both the vector species were found resistant to DDT, malathion and deltamethrin. CONCLUSION: The emergence of insecticide resistance in both vector species, compromises the effectiveness of commonly used public health insecticides. Consequently, the implementation of robust insecticide resistance management strategies becomes imperative. To effectively tackle the malaria transmission, a significant shift in vector control strategies is warranted, with careful consideration and adaptation to address specific challenges encountered in malaria elimination efforts.


Assuntos
Anopheles , Inseticidas , Malária , Piretrinas , Animais , Humanos , Inseticidas/farmacologia , Resistência a Inseticidas , Malária/prevenção & controle , DDT , Controle de Mosquitos/métodos , Mosquitos Vetores , Nitrilas , Índia/epidemiologia
8.
J Pept Sci ; : e3602, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600778

RESUMO

Targeted therapy of the highest globally incident breast cancer shall resolve the issue of off-target toxicity concurring with augmented killing of specific diseased cells. Thus, the goal of this study was to prepare a peptide-drug conjugate targeting elevated expression of HER2 receptors in breast cancer. Towards this, the rL-A9 peptide was conjugated with the chemotherapeutic drug doxorubicin (DOX) through a N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) linker. The synthesized peptide-drug conjugate, rL-A9-DOX, was characterized by mass spectrometry. Molecular docking studies, based on binding energy data, suggested a stronger interaction of rL-A9-DOX with the HER2 receptor in comparison to the unconjugated peptide, rL-A9. The cytotoxic effect of the rL-A9-DOX conjugate was observed to be higher in HER2-positive SKOV3 cells compared to HER2-negative MDA-MB-231 cells, indicating selective cell killing. Cellular internalization of the rL-A9-DOX conjugate was evident from the flow cytometry analysis, where a noticeable shift in mean fluorescent intensity (MFI) was observed for the conjugate compared to the control group. This data was further validated by confocal microscopy, where the fluorescent signal ascertained nuclear accumulation of rL-A9-DOX. The present studies highlight the promising potential of rL-A9-DOX for targeted delivery of the drug into a defined group of cancer cells.

9.
Int J Med Robot ; 20(2): e2629, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38643388

RESUMO

BACKGROUND: Cholecystoduodenal fistula (CDF) arises from persistent biliary tree disorders, causing fusion between the gallbladder and duodenum. Initially, open resection was common until laparoscopic fistula closure gained popularity. However, complexities within the gallbladder fossa yielded inconsistent outcomes. Advanced imaging and robotic surgery now enhance precision and detection. METHOD: A 62-year-old woman with chronic cholangitis attributed to cholecystoduodenal fistula underwent successful robotic cholecystectomy and fistula closure. RESULTS: Postoperatively, the symptoms subsided with no complications during the robotic procedure. Existing studies report favourable outcomes for robotic cholecystectomy and fistula closure. CONCLUSIONS: Our case report showcases a rare instance of successful robotic cholecystectomy with CDF closure. This case, along with a review of previous cases, suggests the potential of robotic surgery as the preferred approach, especially for patients anticipated to face significant laparoscopic morbidity.


Assuntos
Duodenopatias , Doenças da Vesícula Biliar , Fístula Intestinal , Procedimentos Cirúrgicos Robóticos , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Duodenopatias/complicações , Duodenopatias/cirurgia , Doenças da Vesícula Biliar/cirurgia , Colecistectomia/efeitos adversos , Fístula Intestinal/cirurgia , Fístula Intestinal/diagnóstico , Fístula Intestinal/etiologia
10.
IJID Reg ; 11: 100359, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38646508

RESUMO

Rare human pathogens are infrequently observed clinically but can lead to undiagnosed infections, delays in treatment, severe complications, including death. Traditional diagnostic tools cannot routinely detect rare infections in public health settings. This study focuses on the incidence and outcomes of rare pathogenic microorganisms over 13 years (2010-2022) using PubMed database to obtain epidemiological data on rare bacterial, parasitic, and fungal infections in hospitals throughout India. A total of 974 articles were screened using case studies, datasets, comments, classical articles, letters, editorials, observational studies, and meta-analyses. Our analysis identified 28 rare bacteria, six parasites, and five fungal species infections in India. Fatal cases were associated with rare bacterial and fungal infections, including two from pan-drug-resistant bacteria (both from the Myroides genus). A total of 10 bacterial species displayed multi-drug resistance; one was extensively drug-resistant, and eight remained unclassified. Of the 83 patients with these rare infections, the mortality was ∼8.4% (seven of 83). Considering drug resistance and high mortality, prompt diagnosis of rare pathogens is crucial to controlling their spread. An increased awareness within the Indian health care system focusing on diagnostics, record keeping, and data sharing will be necessary to enhance surveillance.

11.
Dig Dis Sci ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499735

RESUMO

INTRODUCTION: Vibration-controlled transient elastography (VCTE) based liver stiffness measurement (LSM) is an excellent 'rule-out' test for advanced hepatic fibrosis in liver transplant (LT) recipients, however, its ability to 'rule-in' the disease is suboptimal. The study aimed to improve diagnostic performance of LSM in LT recipients. METHODS: Adult LT recipients with a liver biopsy and VCTE were included (N = 150). Sequential covering analysis was performed to create rules to identify patients at low or high risk for advanced fibrosis (stage 3-4). RESULTS: Advanced hepatic fibrosis was excluded in patients with either LSM < 7.45 kPa (n = 72) or 7.45 ≤ LSM < 12.1 kPa and time from LT < 5.6 years (n = 25). Conversely, likelihood of advanced fibrosis was 95% if patients had LSM > 14.1 and controlled attenuation parameter > 279 dB/m (n = 21). Thus, 118 (79%) were correctly identified and 32 (21%) would have required a biopsy to establish the diagnosis. Compared to previously established LSM based cutoff values of 10.5 kPa (Youden index) and 13.3 kPa (maximized specificity), the false positive rates of sequential covering analysis was 1% compared to 16.5% with LSM ≥ 10.5 kPa and 8.3% with LSM ≥ 13.3 kPa. The true positive rates were comparable at 87% for sequential covering analysis, 93% for LSM ≥ 10.5 kPa and 83% for LSM ≥ 13.3 kPa. CONCLUSION: The proposed clinical sequential covering analysis allows for better risk stratification when evaluating for advanced fibrosis in LT recipients compared to LSM alone. Additional efforts are necessary to further reduce the number of patients with indeterminate results in whom a liver biopsy may be required.

12.
Int J Biol Macromol ; 265(Pt 1): 130844, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484809

RESUMO

CHT7 is a regulator of quiescence repression in Chlamydomonas reinhardtii. Initially, CHT7's repression activity was thought to be managed by its DNA-binding CXC domain. Later, it was found that the CHT7-CXC domain is dispensable for CHT7's activities. Rather, CHT7's predicted protein domains were proposed to be involved in regulation activities by binding to other repressors in the cell. Yet, it remains unclear why and how CHT7 refrains its CXC domain from participating in any transcriptional activities. The question becomes more intriguing, since CXC binding regions are available in promoter regions of some of the misregulated genes in CHT7 mutant (cht7). Through biophysical experiments and molecular dynamics approaches, we studied the DNA recognition behavior of CHT7-CXC. The results indicate that this domain possesses sequence selectivity due to the differential binding abilities of its subdomains. Further, to understand if the case is that CXC loses its DNA binding capabilities in the vicinity of other repressors, we examined CHT7-CXC's DNA binding stability under the spatial constraint conditions created through fusing CHT7-CXC with AsLOV2. The results show limited ability of CHT7-CXC to withstand steric forces and provide insights to why and how algal cells may hold back CHT7-CXC's indulgence in quiescence repression. CLASSIFICATIONS: Biological Sciences, Biophysics and Computational Biology.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Triglicerídeos , Hidrólise , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , DNA , Transcrição Gênica
13.
J Am Chem Soc ; 146(13): 8991-9003, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38513217

RESUMO

Though immunogenic cell death (ICD) has garnered significant attention in the realm of anticancer therapies, effectively stimulating strong immune responses with minimal side effects in deep-seated tumors remains challenging. Herein, we introduce a novel self-assembled near-infrared-light-activated ruthenium(II) metallacycle, Ru1105 (λem = 1105 nm), as a first example of a Ru(II) supramolecular ICD inducer. Ru1105 synergistically potentiates immunomodulatory responses and reduces adverse effects in deep-seated tumors through multiple regulated approaches, including NIR-light excitation, increased reactive oxygen species (ROS) generation, selective targeting of tumor cells, precision organelle localization, and improved tumor penetration/retention capabilities. Specifically, Ru1105 demonstrates excellent depth-activated ROS production (∼1 cm), strong resistance to diffusion, and anti-ROS quenching. Moreover, Ru1105 exhibits promising results in cellular uptake and ROS generation in cancer cells and multicellular tumor spheroids. Importantly, Ru1105 induces more efficient ICD in an ultralow dose (10 µM) compared to the conventional anticancer agent, oxaliplatin (300 µM). In vivo experiments further confirm Ru1105's potency as an ICD inducer, eliciting CD8+ T cell responses and depleting Foxp3+ T cells with minimal adverse effects. Our research lays the foundation for the design of secure and exceptionally potent metal-based ICD agents in immunotherapy.


Assuntos
Antineoplásicos , Neoplasias , Rutênio , Humanos , Rutênio/farmacologia , Espécies Reativas de Oxigênio , Morte Celular Imunogênica , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Lisossomos , Linhagem Celular Tumoral
14.
Mol Pharm ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477252

RESUMO

The objective of the present work was to evaluate the potential of a nuclear localization signal (NLS) toward facilitating intracellular delivery and enhancement in the therapeutic efficacy of the molecular cargo. Toward this, an in-house synthesized porphyrin derivative, namely, 5-carboxymethyelene-oxyphenyl-10,15,20-tris(4-methoxyphenyl) porphyrin (UTriMA), was utilized for conjugation with the NLS sequence [PKKKRKV]. The three compounds synthesized during the course of the present work, namely DOTA-Lys-NLS, DOTA-UTriMA-Lys-NLS, and DOTA-Lys-UTriMA, were evaluated for cellular toxicity in cancer cell lines (HT1080), wherein all exhibited minimal dark toxicity. However, during photocytotoxicity studies with DOTA-Lys-UTriMA and DOTA-UTriMA-Lys-NLS conjugates in the same cell line, the latter exhibited significantly higher light-dependent toxicity compared to the former. Furthermore, the photocytotoxicity for DOTA-UTriMA-Lys-NLS in a healthy cell line (WI26VA4) was found to be significantly lower than that observed in the cancer cells. Fluorescence cell imaging studies carried out in HT1080 cancer cells revealed intracellular accumulation for the NLS-conjugated porphyrin (DOTA-UTriMA-Lys-NLS), whereas unconjugated porphyrin (DOTA-Lys-UTriMA) failed to do so. To evaluate the radiotherapeutic effects of the synthesized conjugates, all three compounds were radiolabeled with 177Lu, a well-known therapeutic radionuclide with high radiochemical purity (>95%). During in vitro studies, the [177Lu]Lu-DOTA-UTriMA-Lys-NLS complex exhibited the highest cell binding as well as internalization among the three radiolabeled complexes. Biological distribution studies for the radiolabeled compounds were performed in a fibrosarcoma-bearing small animal model, wherein significantly higher accumulation and prolonged retention of [177Lu]Lu-DOTA-UTriMA-Lys-NLS (9.32 ± 1.27% IA/g at 24 h p.i.) in the tumorous lesion compared to [177Lu]Lu-UTriMA-Lys-DOTA (2.3 ± 0.13% IA/g at 24 h p.i.) and [177Lu]Lu-DOTA-Lys-NLS complexes (0.26 ± 0.17% IA/g at 24 h p.i.) were observed. The results of the biodistribution studies were further corroborated by recording serial SPECT-CT images of fibrosarcoma-bearing Swiss mice administered with [177Lu]Lu-DOTA-UTriMA-Lys-NLS at different time points. Tumor regression studies performed with [177Lu]Lu-DOTA-UTriMA-Lys-NLS in the same animal model with two different doses [250 µCi (9.25 MBq) and 500 µCi (18.5 MBq)] resulted in a significant reduction in tumor mass in the treated group of animals. The above results revealed a definite enhancement in the targeting ability of molecular cargo upon conjugation with NLS and hence indicated that this strategy may be helpful for the preparation of drug-NLS conjugates as multimodal agents.

15.
J Exp Clin Cancer Res ; 43(1): 71, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38454454

RESUMO

A firm link between endoplasmic reticulum (ER) stress and tumors has been wildly reported. Endoplasmic reticulum oxidoreductase 1 alpha (ERO1α), an ER-resident thiol oxidoreductase, is confirmed to be highly upregulated in various cancer types and associated with a significantly worse prognosis. Of importance, under ER stress, the functional interplay of ERO1α/PDI axis plays a pivotal role to orchestrate proper protein folding and other key processes. Multiple lines of evidence propose ERO1α as an attractive potential target for cancer treatment. However, the unavailability of specific inhibitor for ERO1α, its molecular inter-relatedness with closely related paralog ERO1ß and the tightly regulated processes with other members of flavoenzyme family of enzymes, raises several concerns about its clinical translation. Herein, we have provided a detailed description of ERO1α in human cancers and its vulnerability towards the aforementioned concerns. Besides, we have discussed a few key considerations that may improve our understanding about ERO1α in tumors.


Assuntos
Glicoproteínas de Membrana , Neoplasias , Humanos , Relevância Clínica , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Glicoproteínas de Membrana/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Oxirredução , Oxirredutases/metabolismo
16.
bioRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38464220

RESUMO

Previous studies have shown that bicyclic azetidines are potent and selective inhibitors of apicomplexan phenylalanine tRNA synthetase (PheRS), leading to parasite growth inhibition in vitro and in vivo, including in models of Toxoplasma infection. Despite these useful properties, additional optimization is required for the development of efficacious treatments of toxoplasmosis from this inhibitor series, in particular to achieve sufficient exposure in the brain. Here, we describe a series of PheRS inhibitors built on a new bicyclic pyrrolidine core scaffold designed to retain the exit-vector geometry of the isomeric bicyclic azetidine core scaffold while offering avenues to sample diverse chemical space. Relative to the parent series, bicyclic pyrrolidines retain reasonable potency and target selectivity for parasite PheRS vs. host. Further structure-activity relationship studies revealed that the introduction of aliphatic groups improved potency, ADME and PK properties, including brain exposure. The identification of this new scaffold provides potential opportunities to extend the analog series to further improve selectivity and potency and ultimately deliver a novel, efficacious treatment of toxoplasmosis.

17.
Clin Transl Immunology ; 13(3): e1500, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529413

RESUMO

Objectives: The rapid recognition of epigenetic manipulation's potential in restricting cancer cell capabilities spurred translational initiatives, including histone deacetylase inhibitors (HDACis). Clinical trials on multiple myeloma (MM) demonstrated substantial benefits of HDACis, coupled with promising outcomes from cytokine-induced killer cell (CIK) immunotherapy. Intriguingly, the unexplored synergy of HDACis and CIK cell immunotherapy in MM prompted our study. Methods: We examined clinically relevant HDACis (panobinostat/LBH589 and romidepsin) alongside CIK cells derived from peripheral blood mononuclear cells across diverse MM cell lines (U266, RPMI8226, OPM-2 and NCI-H929). Utilising various in vitro methodologies, we investigated how HDACis enhance CIK cell lysis of myeloma cells through NKG2D/NKG2D ligand interactions. Results: The results of our analysis indicated several key findings. (1) Enhanced cytotoxicity of CIK cells in MM cells when combined with HDACis. (2) Significant increase in apoptosis, suggesting HDACis and CIK may together enhance apoptotic effects in specific MM cell lines. (3) Elevated IFN-γ secretion and alterations in granzyme B secretion because of the independent activity of HDACis. (4) Notably, HDACis increased the expression of MICA/B and ULBP2, crucial for inducing antitumor cytotoxicity of NKT cells. Validation through NKG2D receptor blocking in CIK cells with a purified mouse antihuman NKG2D antibody further supported our findings. Conclusions: Our analyses provide sufficient evidence to consider this clinically forgotten instance (HDACis-CIK cell combination) as a therapeutic priority for MM treatment. Furthermore, we suggest that NKG2D/NKG2D-ligand interactions activating NK/NKT cells may contribute to enhanced myeloma cell lysis in response to HDACis treatment by CIK cells.

18.
Mol Neurobiol ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429622

RESUMO

Mounting evidence suggests a prominent role for alpha-synuclein (a-syn) in neuronal cell function. Alterations in the levels of cellular a-syn have been hypothesized to play a critical role in the development of Parkinson's disease (PD); however, mechanisms that control expression of the gene for a-syn (SNCA) in cis and trans as well as turnover of a-syn are not well understood. We analyzed whether methyl-CpG binding protein 2 (MeCP2), a protein that specifically binds methylated DNA, thus regulating transcription, binds at predicted binding sites in intron 1 of the SNCA gene and regulates a-syn protein expression. Chromatin immunoprecipitation (ChIP) and electrophoretic mobility-shift assays (EMSA) were used to confirm binding of MeCP2 to regulatory regions of SNCA. Site-specific methylation and introduction of localized mutations by CRISPR/Cas9 were used to investigate the binding properties of MeCP2 in human SK-N-SH neuroblastoma cells. The significance of MeCP2 for SNCA regulation was further investigated by overexpressing MeCP2 and mutated variants of MeCP2 in MeCP2 knockout cells. We found that methylation-dependent binding of MeCP2 at a restricted region of intron 1 of SNCA had a significant impact on the production of a-syn. A single nucleotide substitution near to CpG1 strongly increased the binding of MeCP2 to intron 1 of SNCA and decreased a-syn protein expression by 60%. In contrast, deletion of a single nucleotide closed to CpG2 led to reduced binding of MeCP2 and significantly increased a-syn levels. In accordance, knockout of MeCP2 in SK-N-SH cells resulted in a significant increase in a-syn production, demonstrating that SNCA is a genomic target for MeCP2 regulation. In addition, the expression of two mutated MeCP2 variants found in Rett syndrome (RTT) showed a loss of their ability to reduce a-syn expression. This study demonstrates that methylation of CpGs and binding of MeCP2 to intron 1 of the SNCA gene plays an important role in the control of a-syn expression. In addition, the changes in SNCA regulation found by expression of MeCP2 variants carrying mutations found in RTT patients may be of importance for the elucidation of a new molecular pathway in RTT, a rare neurological disorder caused by mutations in MECP2.

19.
PLoS Pathog ; 20(3): e1011991, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38427625

RESUMO

The emergence of resistance against antimalarials and insecticides poses a significant threat to malaria elimination strategies. It is crucial to explore potential risk factors for malaria to identify new targets and alternative therapies. Malnutrition is a well-established risk factor for malaria. Deficiencies of micronutrients such as vitamin A, zinc, iron, folic acid, and phenotypic measures of malnutrition, such as stunting and wasting, have been studied extensively in the context of malaria. Vitamin B2, also known as riboflavin, is a micronutrient involved in maintaining cellular homeostasis. Riboflavin deficiency has been shown to have an inverse correlation with malarial parasitaemia. This article reviews the role of riboflavin in maintaining redox homeostasis and probes how riboflavin deficiency could alter malaria pathogenesis by disrupting the balance between oxidants and antioxidants. Though riboflavin analogues have been explored as antimalarials, new in vivo and patient-based research is required to target riboflavin-associated pathways for antimalarial therapy.


Assuntos
Antimaláricos , Malária , Deficiência de Riboflavina , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Ácido Fólico , Micronutrientes , Riboflavina
20.
Artigo em Inglês | MEDLINE | ID: mdl-38512632

RESUMO

Tannase-producing filamentous fungi residing alongside tannin-rich ambient in the Northwest Himalayas were isolated at laboratory conditions and further identified by 18S ribosomal RNA gene sequencing. Five most potent tannase producing strains (EI ≥ 2.0), designated Aspergillus fumigatus AN1, Fusarium redolens AN2, Penicillium crustosum AN3, Penicillium restrictum AN4, and Penicillium commune AN5, were characterized. The strain Penicillium crustosum AN3 exhibited a maximum zone dia (25.66 mm ± 0.38). During solid-state fermentation, a maximal amount of tannase was attained with Penicillium crustosum AN3 using pine needles (substrate) by adopting response surface methodology for culture parameter optimization. Gel filtration chromatography yielded 46.48% of the partially purified enzyme with 3.94-fold of tannase purification. We found two subunits in enzyme-117.76 KDa and 88.51 KDa, respectively, in the SDS-PAGE. Furthermore, the characterization of partially purified tannase revealed a maximum enzyme activity of 8.36 U/mL at 30 °C using a substrate concentration (methyl gallate) of 10 mM. To broaden the knowledge of crude enzyme application, dye degradation studies were subjected to extracellular crude tannase from Penicillium crustosum AN3 where the maximum degradation achieved at a low enzyme concentration (5 ppm).

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