Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Int J Biol Macromol ; 278(Pt 4): 134781, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151860

RESUMO

Local administration of drugs at tumor sites over an extended period of time shows potential as a promising approach for cancer treatment. In the present study, the temperature-induced phase transition of chitosan and poloxamer 407 is used to construct an injectable hydrogel encapsulating 5-FU-loaded nanoerythrosome (5-FU-NER-gel). The 5-FU-NERs were found to be spherical, measuring approximately 115 ± 20 nm in diameter and having a surface potential of -7.06 ± 0.4. The drug loading efficiency was approximately 40 %. In situ gel formation took place within 15 s when the gel was exposed to body temperature or subcutaneous injection. A sustained release profile was observed at pH 7.4 and 6.8, with a total 5-FU release of 76.57 ± 4.4 and 98.07 ± 6.31 in 24 h, respectively. MTT, Live/dead, and migration assays confirmed the cytocompatibility of the drug carrier and its effectiveness as a chemotherapeutic formulation. After in vivo antitumor assessment in a subcutaneous autograft model, it was demonstrated that tumor growth inhibition in 14 days was 90 %. Therefore, the obtained injectable chitosan-based hydrogel containing 5-FU-loaded nanoerythrosomes illustrated promising potential as a candidate for local and enhanced delivery of chemotherapeutics at the tumor site.

2.
ACS Biomater Sci Eng ; 10(3): 1207-1234, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38416058

RESUMO

Biomaterials possess distinctive properties, notably their ability to encapsulate active biological products while providing biocompatible support. The immune system plays a vital role in preventing cancer recurrence, and there is considerable demand for an effective strategy to prevent cancer recurrence, necessitating effective strategies to address this concern. This review elucidates crucial cellular signaling pathways in cancer recurrence. Furthermore, it underscores the potential of biomaterial-based tools in averting or inhibiting cancer recurrence by modulating the immune system. Diverse biomaterials, including hydrogels, particles, films, microneedles, etc., exhibit promising capabilities in mitigating cancer recurrence. These materials are compelling candidates for cancer immunotherapy, offering in situ immunostimulatory activity through transdermal, implantable, and injectable devices. They function by reshaping the tumor microenvironment and impeding tumor growth by reducing immunosuppression. Biomaterials facilitate alterations in biodistribution, release kinetics, and colocalization of immunostimulatory agents, enhancing the safety and efficacy of therapy. Additionally, how the method addresses the limitations of other therapeutic approaches is discussed.


Assuntos
Materiais Biocompatíveis , Neoplasias , Humanos , Materiais Biocompatíveis/uso terapêutico , Distribuição Tecidual , Sistemas de Liberação de Medicamentos , Imunoterapia , Neoplasias/tratamento farmacológico , Microambiente Tumoral
3.
Heliyon ; 9(6): e17082, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484272

RESUMO

Glioma is an intra-cranial malignancy with the origin of neural stem cells or precursor cells, the most prevalent brain tumor worldwide. Glioblastoma, the fourth-grade glioma, is a common brain tumor whose incidence rate is 5-7 people per 100,000 populations annually. Despite their high mortality rate, all efforts for treatment have yet to achieve any desirable clinical outcome. The Wnt signaling pathway is a conserved pathway among species that seems to be a candidate for cancer therapy by its inhibition. Metformin is a known inhibitor of the Wnt signaling pathway. Its effects on glioma treatment have been observed in cellular, animal, and clinical experiments. Nanoerythrosomes are drug carriers obtained from the cellular membrane of red blood cells in nano size which can offer several characteristics to deliver metformin to brain tumors. They are good at loading and carrying hydrophilic drugs, they can protect metformin from its metabolizing enzymes, which are present in the blood-brain barrier, and they can extend the period of metformin presence in circulation. In this study, nanoerythrosomes were prepared by using the hypotonic buffer. They had particle sizes in the range of 97.1 ± 34.2 nm, and their loading efficiency and loading capacity were 72.6% and 1.66%, respectively. Nanoerythrosomes could reserve metformin in their structure for a long time, and only 50% of metformin was released after 30 h. Moreover, they released metformin at a low and approximately constant rate. Besides, nanoerythrosomes could tolerate various kinds of stress and maintain most of the drug in their structure. Altogether, nanoerythrosome can be a suitable drug delivery system to deliver therapeutic amounts of metformin to various tissues.

4.
Neurooncol Pract ; 10(2): 169-175, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36970173

RESUMO

Background: Primary central nervous system lymphomas (PCNSLs) have historically had dismal survival rates until the advent of high-dose methotrexate (HD-MTX) based chemotherapy regimens. With increasing prevalence of autoimmune disease and development of new immunosuppressants, a genetically distinct entity known as iatrogenic immunodeficiency-associated lymphoproliferative disorder (LPD) has emerged. Many of these cases arise following methotrexate use, challenging feasibility of standard HD-MTX regimens. The aim of this study was to further characterize this disorder and determine the optimal management strategy. Methods: We describe a case of a 76-year-old female with iatrogenic immunodeficiency-associated PCNSL successfully treated with surgical resection followed by an antiviral and rituximab based regimen. We then performed a systematic literature review and identified 58 cases of non-transplant iatrogenic immunodeficiency-associated LPD involving the CNS. We used a linear probability statistical model to determine correlations with outcome. Results: Natalizumab was associated with EBV negative tumors (P = .023), and EBV positive tumors were associated with improved outcomes (P = .016). Surgical resection was associated with improved outcomes (P = .032), although limited by potential confounding effect. Antiviral treatment (P = .095), rituximab (P = .111), and stem cell transplant (SCT) (P = .198) showed a trend toward improved outcomes. The remaining treatments including methotrexate showed no improvement. Conclusion: We propose that surgical resection, rituximab, and antiviral treatment may be considered as an alternative to standard HD-MTX based regimens when managing iatrogenic immunodeficiency-associated LPD of the CNS. Further study through prospective cohort studies or randomized clinical trials is warranted.

5.
Mol Pharm ; 20(3): 1531-1548, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36763486

RESUMO

The blood-brain barrier (BBB) acts as a physical/biochemical barrier that protects brain parenchyma from potential hazards exerted by different xenobiotics found in the systemic circulation. This barrier is created by "a lipophilic gate" as well as a series of highly organized influx/efflux mechanisms. The BBB bottleneck adversely affects the efficacy of chemotherapeutic agents in treating different CNS malignancies such as glioblastoma, an aggressive type of cancer affecting the brain. In the present study, mesoporous silica nanoparticles (MSNs) were conjugated with the transactivator of transcription (TAT) peptide, a cell-penetrating peptide, to produce MSN-NH-TAT with the aim of improving methotrexate (MTX) penetration into the brain. The TAT-modified nanosystem was characterized by Fourier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DLS), and N2 adsorption-desorption analysis. In vitro hemolysis and cell viability studies confirmed the biocompatibility of the MSN-based nanocarriers. In addition, in vivo studies showed that the MTX-loaded MSN-NH-TAT improved brain-to-plasma concentration ratio, brain uptake clearance, and the drug's blood terminal half-life, compared with the use of free MTX. Taken together, the results of the present study indicate that MSN functionalization with TAT is crucial for delivery of MTX into the brain. The present nanosystem represents a promising alternative drug carrier to deliver MTX into the brain via overcoming the BBB.


Assuntos
Peptídeos Penetradores de Células , Glioblastoma , Nanopartículas , Humanos , Metotrexato , Dióxido de Silício/química , Portadores de Fármacos/química , Nanopartículas/química , Encéfalo , Sistemas de Liberação de Medicamentos/métodos , Porosidade
6.
Cureus ; 14(11): e31449, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36523718

RESUMO

Glioneuronal tumors are rare central nervous system tumors with heterogeneous histological and molecular features. While the majority are low grade, a small percentage can behave aggressively. Due to the rarity of these tumors, there is no consensus on how to treat high-grade glioneuronal tumors, and they are often managed similarly to glial tumors. With the advent of molecular profiling, management decisions are increasingly determined by molecular alterations in the tumor rather than the tumor type, which can be a useful approach for tumor types that do not have robust supportive clinical trial data due to low prevalence. We present a case of an 18-year-old patient with a high-grade glioneuronal neoplasm initially treated with craniospinal irradiation, vincristine, and cyclophosphamide. He presented eight years later with a recurrent tumor and was found to be positive for MEF2D-NTRK1 fusion. He was treated with surgical resection and postoperative intensity-modulated radiation therapy (IMRT; 55.8 Gy) with concurrent temozolomide, followed by the NTRK inhibitor larotrectinib. He achieved a radiographic response, with a decrease in residual enhancement and radiographic improvement over the course of treatment. He remained in clinical and radiographic remission for six months. This demonstrates the successful treatment of a high-grade glioneuronal NTRK fusion-positive tumor with larotrectinib, which has only been previously reported once in the literature.

7.
Cureus ; 14(6): e26457, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35923675

RESUMO

PURPOSE: This study describes a retrospective case series of patients with glioma who received ketogenic metabolic therapy through dietary adherence and intermittent fasting. METHODS: A retrospective chart review of a single surgeon's clinic records was performed to identify patients who maintained nutritional ketosis for at least four months between January 2015 and October 2020. RESULTS: Sixteen patients who met the inclusion criteria constituted a heterogeneous population of patients with diagnoses including eight World Health Organization (WHO) grade IV gliomas (seven glioblastoma, one gliosarcoma), seven WHO grade III gliomas (three oligodendroglioma, four astrocytoma), and one WHO grade II oligodendroglioma. IDH1 mutation status was present for 12 patients, and MGMT methylation status was present for eight patients. The mean (standard deviation [SD]) duration of ketogenic metabolic therapy was 20.6 (13.8) months. The Response Assessment in Neuro-oncology Criteria was applied during the ketogenic metabolic therapy interval, indicating a complete response in eight patients and partial response in eight patients. The mean (SD) progression-free survival while patients maintained ketogenic metabolic therapy was 20.0 (14.4) months. CONCLUSION: Ketogenic metabolic therapy appears to convey a survival advantage within this patient series, which highlights the possibility that this therapy, when strictly applied, can augment the standard of care. Further exploration of this modality in a prospective series is warranted to formally explore this therapy.

8.
Neurooncol Adv ; 4(1): vdac096, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35821680

RESUMO

Background: The genomic and overall biologic landscape of glioblastoma (GB) has become clearer over the past 2 decades, as predictive and prognostic biomarkers of both de novo and transformed forms of GB have been identified. The oral chemotherapeutic agent temozolomide (TMZ) has been integral to standard-of-care treatment for nearly 2 decades. More recently, the use of non-pharmacologic interventions, such as application of alternating electric fields, called Tumor-Treating Fields (TTFields), has emerged as a complementary treatment option that increases overall survival (OS) in patients with newly diagnosed GB. The genomic factors associated with improved or lack of response to TTFields are unknown. Methods: We performed comprehensive genomic analysis of GB tumors resected from 55 patients who went on to receive treatment using TTFields, and compared results to 57 patients who received standard treatment without TTFields. Results: We found that molecular driver alterations in NF1, and wild-type PIK3CA and epidermal growth factor receptor (EGFR), were associated with increased benefit from TTFields as measured by progression-free survival (PFS) and OS. There were no differences when stratified by TP53 status. When NF1, PIK3CA, and EGFR status were combined as a Molecular Survival Score, the combination of the 3 factors significantly correlated with improved OS and PFS in TTFields-treated patients compared to patients not treated with TTFields. Conclusions: These results shed light on potential driver and passenger mutations in GB that can be validated as predictive biomarkers of response to TTFields treatment, and provide an objective and testable genomic-based approach to assessing response.

9.
Nanomedicine ; 44: 102575, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35714923

RESUMO

A cell-based drug delivery system based on yeast-cell wall loaded with sitagliptin, a drug with an anti-inflammatory effect, was developed to control neuroinflammation associated with Alzheimer's disease. The optimized nanoparticles had a spherical shape with a negative surface charge, and were shown to be less toxic than the carrier and sitagliptin. Moreover, the nanoparticles caused anti-inflammatory effects against tumor necrosis factor-alpha in mice model of neuroinflammation. The pharmacokinetics study showed the brain concentration of drug in the nanoparticles group was much higher than in the control group. To evaluate the effect of P-glycoprotein on brain entry of sitagliptin, the experiment was repeated with verapamil, as a P-glycoprotein inhibitor. Brain concentration of the nanoparticles group remained approximately unchanged, proving the "Trojan Horse" effect of the developed nanocarriers. The results are promising for using yeast-cell wall as a carrier for targeted delivery to immune cells for the management of inflammation.


Assuntos
Doença de Alzheimer , Subfamília B de Transportador de Cassetes de Ligação de ATP/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Anti-Inflamatórios/uso terapêutico , Parede Celular/metabolismo , Camundongos , Doenças Neuroinflamatórias , Saccharomyces cerevisiae , Fosfato de Sitagliptina/farmacologia , Fosfato de Sitagliptina/uso terapêutico
10.
Cureus ; 13(9): e17659, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34646701

RESUMO

Here, we report a case of Burkitt's lymphoma in an HIV-positive patient presenting with features suggestive of Vogt-Koyanagi-Harada disease (VKHD), which in retrospect was likely a misdiagnosis. We hope to describe a rare presentation of lymphoma in order to prevent misdiagnosis and promote early recognition. The patient was a 25-year-old male who initially presented with right eye pain and blurry vision. He was found to have bilateral serous retinal detachments and was diagnosed with VKHD and started on prednisone. He stopped taking the prednisone, and his vision worsened. He then developed right eye ptosis, restricted eye movements, nausea, vomiting, headache, dysphagia, tongue deviation, and slurred speech. MRI showed diffuse cranial nerve enhancement. He was found to be positive for HIV and Hepatitis A with CD4 count of 41. Lumbar puncture showed WBC 83 (94% lymphocytes), RBC 1460, glucose 62, and protein 195, with Epstein-Barr virus (EBV) positivity and negative cytology. Gd1a antibody was positive (72). He underwent empiric treatment with IV solumedrol for possible VKHD exacerbation, followed by empiric intravenous immune globulin (IVIG) for possible acute inflammatory demyelinating polyneuropathy (AIDP). He subsequently developed diffuse limb weakness and loss of reflexes, and he was treated with plasma exchange (PLEX). He demonstrated minimal response to treatment. Electromyography (EMG) was unrevealing, and the MRI of the cervical and lumbar spine showed diffuse nerve root thickening and enhancement. He underwent an esophagogastroduodenoscopy (EGD) for continued dysphagia, and the biopsy was positive for an aggressive B-cell lymphoma strongly favoring Burkitt's lymphoma. VKHD is a rare condition diagnosed based on retinal exam findings. Few cases of lymphoma report findings suggestive of VKHD. This is a rare case of lymphoma initially presenting with these retinal findings. Understanding this potential presentation of lymphoma is essential for early diagnosis and treatment and for optimizing patient outcomes.

11.
Endocrinol Diabetes Metab ; 4(3): e00246, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34268454

RESUMO

Introduction: The coronavirus disease 2019 (COVID-19) is currently a major pandemic challenge, and cancer patients are at a heightened risk of severity and mortality from this infection. In recent years, immune checkpoint inhibitor (ICI) use to treat multiple cancers has increased in oncology, but equally has raised the question of whether ICI therapy and its side-effects is harmful or beneficial during this pandemic. Methods: A combination of published literature in PubMed between January 2010 and December 2020, recommended guidelines in non-cancer patients, and clinical experience was utilized to outline recommendations on glucocorticoid timing and dosing regimens in ICI-treated patients presenting with AI during this COVID-19 pandemic. Results: The potential immune interaction between ICIs and COVID-19 require major consideration because these agents act at the intersection between effective cancer immunotherapy and increasing patient susceptibility, severity and complications from the SARS-CoV-2 sepsis. Furthermore, ICI use can induce autoimmune adrenal insufficiency (AI) that further increases infection susceptibility. Thus, ICI-treated cancer patients with AI may be at greater risk of COVID-19 infection. Glucocorticoids are the cornerstone for replacement therapy, and for treatment and mitigation of adrenal crisis and relief of mass effects in ICI-related hypophysitis. High-dose glucocorticoids have also been used with cytotoxic chemotherapy as part of cancer treatment, and iatrogenic AI may arise after glucocorticoid discontinuation that increases the risk of adrenal crisis. Furthermore, in patients who develop the "long COVID-19" syndrome, when to discontinue glucocorticoid therapy becomes crucial to avoid unnecessary prolongation of therapy and the development of iatrogenic hypercortisolemia. Conclusion: During the COVID-19 pandemic, much of cancer care have been impacted and an important clinical question is how to optimally manage ICI-related AI during these unprecedented times. Herein, we suggest practical recommendations on the timing and dosing regimens of glucocorticoids in different clinical scenarios of ICI-treated cancer patients presenting with AI during this COVID-19 pandemic.


Assuntos
Insuficiência Adrenal/tratamento farmacológico , COVID-19 , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias/tratamento farmacológico , Insuficiência Adrenal/induzido quimicamente , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Pandemias
12.
J Pain Symptom Manage ; 62(5): 1020-1025, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33933624

RESUMO

CONTEXT: Early access to palliative care is a critical component of treating patients with advanced cancer, particularly for glioblastoma patients who have low rates of survival despite optimal therapies. Additionally, there are unique considerations for primary brain tumor patients given the need for management of headaches, seizures, and focal neurological deficits. OBJECTIVE: We hoped to determine Sub-Saharan African physicians' level of understanding and skill in providing palliative care, types of palliative care therapies provided, role of cultural beliefs, availability of resources, and challenges faced. METHODS: We conducted a survey of 109 physicians in Sub-Saharan Africa who treat brain tumor patients. RESULTS: Among the participants, 48% felt comfortable in providing palliative care consultations, 52% believed that palliative care is only appropriate when there is irreversible deterioration, 62% expressed having access to palliative care, 49% do not have access to liquid opioid agents, 50% stated that cultural beliefs held by the patient or family prevented them from receiving palliative care, and 23% stated that their own beliefs affected palliative care delivery. Older providers (age > 30) had a clearer understanding of palliative care (P = 0.004), were more comfortable providing consultation (P = 0.052), and were more likely to address mental health (P < 0.001). CONCLUSION: Palliative care delivery to glioblastoma patients in Sub-Saharan Africa is often delayed until late in the disease course. Barriers to adequate palliative care treatment identified in this survey study include lack of training, limited access to liquid opioid agents, and cultural beliefs.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Médicos , África Subsaariana , Humanos , Cuidados Paliativos , Inquéritos e Questionários
13.
Adv Sci (Weinh) ; 8(8): 2002499, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33898169

RESUMO

Over the past decades, considerable attention has been dedicated to the exploitation of diverse immune cells as therapeutic and/or diagnostic cell-based microrobots for hard-to-treat disorders. To date, a plethora of therapeutics based on alive immune cells, surface-engineered immune cells, immunocytes' cell membranes, leukocyte-derived extracellular vesicles or exosomes, and artificial immune cells have been investigated and a few have been introduced into the market. These systems take advantage of the unique characteristics and functions of immune cells, including their presence in circulating blood and various tissues, complex crosstalk properties, high affinity to different self and foreign markers, unique potential of their on-demand navigation and activity, production of a variety of chemokines/cytokines, as well as being cytotoxic in particular conditions. Here, the latest progress in the development of engineered therapeutics and diagnostics inspired by immune cells to ameliorate cancer, inflammatory conditions, autoimmune diseases, neurodegenerative disorders, cardiovascular complications, and infectious diseases is reviewed, and finally, the perspective for their clinical application is delineated.


Assuntos
Doenças Autoimunes/terapia , Biomimética/métodos , Doenças Transmissíveis/terapia , Inflamação/terapia , Nanomedicina/métodos , Neoplasias/terapia , Animais , Doenças Autoimunes/imunologia , Doenças Transmissíveis/imunologia , Sistemas de Liberação de Medicamentos/métodos , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Imunoterapia/métodos , Inflamação/imunologia , Camundongos , Nanopartículas/administração & dosagem , Neoplasias/imunologia
14.
Neurooncol Pract ; 8(2): 109-116, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33889416

RESUMO

Coronavirus disease 2019 (COVID-19) has grossly affected how we deliver health care and how health care institutions derive value from the care provided. Adapting to new technologies and reimbursement patterns were challenges that had to be met by the institutions while patients struggled with decisions to prioritize concerns and to identify new pathways to care. With the implementation of social distancing practices, telemedicine plays an increasing role in patient care delivery, particularly in the field of neurology. This is of particular concern in our cancer patient population given that these patients are often at increased infectious risk on immunosuppressive therapies and often have mobility limitations. We reviewed telemedicine practices in neurology pre- and post-COVID-19 and evaluated the neuro-oncology clinical practice approaches of 2 large care systems, Barrow Neurological Institute and Geisinger Health. Practice metrics were collected for impact on clinic volumes, institutional recovery techniques, and task force development to address COVID-19 specific issues. Neuro-Oncology divisions reached 67% or more of prepandemic capacity (patient visits and slot utilization) within 3 weeks and returned to 90% or greater capacity within 6 weeks of initial closures due to COVID-19. The 2 health systems rapidly and effectively implemented telehealth practices to recover patient volumes. Although telemedicine will not replace the in-person clinical visit, telemedicine will likely continue to be an integral part of neuro-oncologic care. Telemedicine has potential for expanding access in remote areas and provides a convenient alternative to patients with limited mobility, transportation, or other socioeconomic complexities that otherwise challenge patient visit adherence.

15.
Chin Clin Oncol ; 10(4): 35, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32279523

RESUMO

Glioblastoma is an aggressive disease that is difficult to treat, in large part due to the high level of molecular heterogeneity that limits the utility of targeted therapies. As such, population studies have been essential in characterizing the factors that promote survival. In this review, we summarize the findings in these studies. Demographic trends, molecular markers (IDH mutation, MGMT promoter methylation, TERT promoter mutation, chromosome 1p19q codeletion, PTEN, and p53 among others), radiographic correlates (peritumoral edema, enhancement, cyst formation, necrosis, and invasion among others), nonsteroidal anti-inflammatory drug (NSAID) and statin use, and ketogenic diet have been assessed. Overall, studies have found that IDH mutation and MGMT promoter methylation are positive prognostic markers and TERT is a negative prognostic marker, although subgroup analysis has revealed differential responses. NSAID and statin use have also suggested improved survival reaching significance in some studies. Ketogenic diet has not yet been adequately assessed. Further studies to characterize the interplay of these and other genetic and environmental factors are warranted.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/fisiopatologia , Metilação de DNA , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Glioblastoma/epidemiologia , Glioblastoma/genética , Glioblastoma/fisiopatologia , Humanos , Isocitrato Desidrogenase/genética , Prognóstico
16.
ACS Chem Neurosci ; 11(24): 4060-4072, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33251792

RESUMO

Apolipoprotein J (ApoJ), or clusterin, is one of the main apolipoproteins in the brain. It is synthesized and released from astrocytes in a healthy brain, and its expression increases in neurodegenerative disorders. Genetic evidence has suggested an association between ApoJ polymorphism and the risk of Alzheimer's disease (AD)-it is now considered the third main genetic risk factor for late-onset AD. However, the role of ApoJ overexpression in the state of disorder, toxicity, or protection is not yet clear. Since ApoJ plays different roles in AD, we review the function of ApoJ using different cell signaling pathways in AD and outline its paradoxical roles in AD. ApoJ helps in amyloid-beta (Aß) clearance. Vice versa, ApoJ gene knock-out causes fibrillary Aß reduction and prevents Aß-induced neuron cell death. Understanding ApoJ, through various cellular signaling pathways, creates a new perspective on AD's cellular principles. The overall message is that ApoJ can be a valuable tool in controlling AD.


Assuntos
Doença de Alzheimer , Clusterina , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Apolipoproteínas E , Clusterina/genética , Clusterina/metabolismo , Humanos , Transdução de Sinais
17.
Med Hypotheses ; 143: 110111, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32721805

RESUMO

Patients with SARS-CoV-2 infections experience lymphopenia and inflammatory cytokine storms in the severe stage of the disease, leading to multi-organ damage. The exact pattern of immune system changes and their condition during the disease process is unclear. The available knowledge has indicated that the NF-kappa-B pathway, which is induced by several mediators, has a significant role in cytokine storm through the various mechanisms. Therefore, identifying the state of the immune cells and the dominant mechanisms for the production of cytokines incorporated in the cytokine storm can be a critical step in the therapeutic approach. On the other hand, some studies identified a higher risk for diabetic patients. Diabetes mellitus exhibits a close association with inflammation and increases the chance of developing COVID-19. Patients with diabetes mellitus have shown to have more virus entry, impaired immunity response, less viral elimination, and dysregulated inflammatory cytokines. The parallel analysis of COVID-19 and diabetes mellitus pathogenesis has proposed that the control of the inflammation through the interfering with the critical points of major signaling pathways may provide the new therapeutic approaches. In recent years, the role of Dipeptidyl Peptidase 4 (DPP4) in chronic inflammation has been proved. Numerous immune cells express the DPP4 protein. DPP4 regulates antibody production, cytokine secretion, and immunoglobulin class switching. DPP4 inhibitors like sitagliptin reduce inflammation intensity in different states. Following the accumulating data, we hypothesize that sitagliptin might reduce COVID-19 severity. Sitagliptin, an available DPP4 inhibitor drug, showed multidimensional anti-inflammatory effects among diabetic patients. It reduces the inflammation mostly by affecting on NF-kappa-B signaling pathway. Under the fact that inflammatory mediators are active in individuals with COVID-19, blocking the predominant pathway could be helpful.


Assuntos
Infecções por Coronavirus/complicações , Complicações do Diabetes/tratamento farmacológico , Inflamação/fisiopatologia , Pneumonia Viral/complicações , Fosfato de Sitagliptina/farmacologia , COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Citocinas , Complicações do Diabetes/virologia , Diabetes Mellitus/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Humanos , Resistência à Insulina , Modelos Teóricos , Subunidade p50 de NF-kappa B/metabolismo , Pandemias , Pneumonia Viral/tratamento farmacológico , Transdução de Sinais , Tratamento Farmacológico da COVID-19
18.
ACS Chem Neurosci ; 11(5): 783-795, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32043866

RESUMO

The objective of this study was to formulate and investigate the neuropharmacokinetics and pharmacodynamics of rivastigmine (Riv) loaded methoxy poly(ethylene glycol)-co-poly(ε-caprolactone) (MPEG-PCL) nanoparticles (Riv-NPs) in rats after IV administration. The MPEG-PCL was synthesized via ring-opening polymerization of ε-caprolactone by MPEG and used to prepare Riv-NPs by the nanoprecipitation method. Response surface D-optimal design was applied to optimize Riv-NPs drug delivery system. The optimized formulation showed a particle size (PS) of 98.5 ± 2.1 nm, drug loading (DL) of 19.2 ± 1.1%, and sustained release behavior of the drug. Moreover, the optimized Riv-NPs were characterized by AFM and DSC analyses. A simple and sensitive HPLC-DAD method for bioanalysis was developed and successfully applied to the pharmacokinetic study. The neuropharmacokinetic study in rats indicated that the integration plot was linear, and the brain uptake clearance of the drug-loaded in MPEG-PCL NPs was significantly higher than the free drug. Furthermore, results of pharmacodynamic studies using the Morris water maze test demonstrated faster regain of memory loss with Riv-NPs when compared to the free drug solution. The results revealed that the mentioned biodegradable nanoparticle holds promise as a suitable drug carrier for brain drug delivery.


Assuntos
Nanopartículas , Poliésteres , Animais , Encéfalo , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Tamanho da Partícula , Polietilenoglicóis , Ratos , Rivastigmina
19.
Curr Drug Discov Technol ; 17(5): 616-618, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31264550

RESUMO

BACKGROUND: Non-Hodgkin's lymphomas (NHL), derived from B- or T-cell, consist of a heterogeneous group of malignant lymphoproliferative disorders. Knockdown of Casein kinase 2 interacting protein-1 (CKIP-1) in NHL promoted cell proliferation and inhibited apoptosis via enhancing phosphorylated Protein Kinase B (PKB or AKT) expression. Statins are the class of drugs that inhibit the ratelimiting step of the mevalonate pathway, which is essential for the biosynthesis of various compounds, including cholesterol. Also, statins have anticancer properties being mediated by different mechanisms. METHODS: A search on databases like Scopus and PubMed with keywords such as statin and non- Hodgkin's lymphomas was performed and Kyoto Encyclopedia of Genes and Genomes (KEGG) website was used to evaluate and reconfirm the involved cellular signaling pathway. RESULTS: CKIP-1 is involved in the regulation of cell proliferation and apoptosis while plays an important role in many cancers. We can hypothesize that statins may increase the expression levels of CKIP-1 which could contribute to the reductions in phospho-AKT level. Hence, they may ameliorate the NHL patients via suppressing AKT phosphorylation and increasing CKIP- expression. CONCLUSION: Present review confirms the positive effect of statins on NHL by increasing CKIP-1 and reducing cell proliferation, subsequently.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Linfoma não Hodgkin/tratamento farmacológico , Linhagem Celular Tumoral , Ensaios Clínicos como Assunto , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma não Hodgkin/patologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Resultado do Tratamento
20.
J Theor Biol ; 483: 109992, 2019 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-31493485

RESUMO

Signal integration has a crucial role in the cell fate decision and dysregulation of the cellular signaling pathways is a primary characteristic of cancer. As a signal integrator, mTOR shows a complex dynamical behavior which determines the cell fate at different cellular processes levels, including cell cycle progression, cell survival, cell death, metabolic reprogramming, and aging. The dynamics of the complex responses to rapamycin in cancer cells have been attributed to its differential time-dependent inhibitory effects on mTORC1 and mTORC2, the two main complexes of mTOR. Two explanations were previously provided for this phenomenon: 1-Rapamycin does not inhibit mTORC2 directly, whereas it prevents mTORC2 formation by sequestering free mTOR protein (Le Chatelier's principle). 2-Components like Phosphatidic Acid (PA) further stabilize mTORC2 compared with mTORC1. To understand the mechanism by which rapamycin differentially inhibits the mTOR complexes in the cancer cells, we present a mathematical model of rapamycin mode of action based on the first explanation, i.e., Le Chatelier's principle. Translating the interactions among components of mTORC1 and mTORC2 into a mathematical model revealed the dynamics of rapamycin action in different doses and time-intervals of rapamycin treatment. This model shows that rapamycin has stronger effects on mTORC1 compared with mTORC2, simply due to its direct interaction with free mTOR and mTORC1, but not mTORC2, without the need to consider other components that might further stabilize mTORC2. Based on our results, even when mTORC2 is less stable compared with mTORC1, it can be less inhibited by rapamycin.


Assuntos
Modelos Biológicos , Neoplasias/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Humanos , Cinética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Sirolimo/farmacologia , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA