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1.
Artigo em Inglês | MEDLINE | ID: mdl-38802678

RESUMO

Lewisite, a chemical warfare agent, causes skin blisters, erythema, edema, and inflammation, requiring mitigation strategies in case of accidental or deliberate exposure. 4-phenyl butyric acid (4-PBA), a chemical chaperone, reduces endoplasmic reticulum stress and skin inflammation. The study aimed to encapsulate 4-PBA in microsponges for effective, sustained delivery against lewisite injury. Porous microsponges in a topical gel would potentially sustain delivery and improve residence time on the skin. Microsponges were developed using the quasi-emulsion solvent diffusion method with Eudragit RS100. Optimized formulation showed 10.58%w/w drug loading was incorporated in a carboxymethylcellulose (CMC) and Carbopol gel for in vitro release and permeation testing using dermatomed human skin. A sustained release was obtained from all vehicles in the release study, and IVPT results showed that compared to the control (41.52 ± 2.54 µg/sq.cm), a sustained permeation profile with a reduced delivery was observed for microsponges in PBS (14.16 ± 1.23 µg/sq.cm) along with Carbopol 980 gel (12.55 ± 1.41 µg/sq.cm), and CMC gel (10.09 ± 1.23 µg/sq.cm) at 24 h. Optimized formulation showed significant protection against lewisite surrogate phenyl arsine oxide (PAO) challenged skin injury in Ptch1+/-/SKH-1 hairless mice at gross and molecular levels. A reduction in Draize score by 29%, a reduction in skin bifold thickness by 8%, a significant reduction in levels of IL-1ß, IL6, and GM-CSF by 54%, 30%, and 55%, respectively, and a reduction in apoptosis by 31% was observed. Thus, the translational feasibility of 4-PBA microsponges for effective, sustained delivery against lewisite skin injury is demonstrated.

2.
J Pharmacol Exp Ther ; 388(2): 605-612, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37699712

RESUMO

Arsenicals are deadly chemical warfare agents that primarily cause death through systemic capillary fluid leakage and hypovolemic shock. Arsenical exposure is also known to cause acute kidney injury, a condition that contributes to arsenical-associated death due to the necessity of the kidney in maintaining whole-body fluid homeostasis. Because of the global health risk that arsenicals pose, a nuanced understanding of how arsenical exposure can lead to kidney injury is needed. We used a nontargeted transcriptional approach to evaluate the effects of cutaneous exposure to phenylarsine oxide, a common arsenical, in a murine model. Here we identified an upregulation of metabolic pathways such as fatty acid oxidation, fatty acid biosynthesis, and peroxisome proliferator-activated receptor (PPAR)-α signaling in proximal tubule epithelial cell and endothelial cell clusters. We also revealed highly upregulated genes such as Zbtb16, Cyp4a14, and Pdk4, which are involved in metabolism and metabolic switching and may serve as future therapeutic targets. The ability of arsenicals to inhibit enzymes such as pyruvate dehydrogenase has been previously described in vitro. This, along with our own data, led us to conclude that arsenical-induced acute kidney injury may be due to a metabolic impairment in proximal tubule and endothelial cells and that ameliorating these metabolic effects may lead to the development of life-saving therapies. SIGNIFICANCE STATEMENT: In this study, we demonstrate that cutaneous arsenical exposure leads to a transcriptional shift enhancing fatty acid metabolism in kidney cells, indicating that metabolic alterations might mechanistically link topical arsenical exposure to acute kidney injury. Targeting metabolic pathways may generate promising novel therapeutic approaches in combating arsenical-induced acute kidney injury.


Assuntos
Injúria Renal Aguda , Arsenicais , Camundongos , Humanos , Animais , Células Endoteliais/metabolismo , Rim/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Injúria Renal Aguda/metabolismo , Células Epiteliais/metabolismo , Ácidos Graxos/metabolismo , Arsenicais/efeitos adversos , Arsenicais/metabolismo
3.
J Pharmacol Exp Ther ; 388(2): 546-559, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37914412

RESUMO

Vesicants such as arsenicals and mustards produce highly painful cutaneous inflammatory and blistering responses, hence developed as chemical weapons during World War I/II. Here, using lewisite and sulfur mustard surrogates, namely phenylarsine oxide (PAO) and 2-chloroethyl ethyl sulfide (CEES), respectively, we defined a common underlying mechanism of toxic action by these two distinct classes of vesicants. Murine skin exposure to these chemicals causes tissue destruction characterized by increase in skin bifold thickness, Draize score, infiltration of inflammatory cells, and apoptosis of epidermal and dermal cells. RNA sequencing analysis identified ∼346 inflammatory genes that were commonly altered by both PAO and CEES, along with the identification of cytokine signaling activation as the top canonical pathway. Activation of several proinflammatory genes and pathways is associated with phosphorylation-dependent activation of heat shock protein 90α (p-HSP90α). Topical treatment with known HSP90 inhibitors SNX-5422 and IPI-504 post PAO or CEES skin challenge significantly attenuated skin damage including reduction in overall skin injury and clinical scores. In addition, highly upregulated inflammatory genes Saa3, Cxcl1, Ccl7, IL-6, Nlrp3, Csf3, Chil3, etc. by both PAO and CEES were significantly diminished by treatment with HSP90 inhibitors. These drugs not only reduced PAO- or CEES-induced p-HSP90α expression but also its client proteins NLRP3 and pP38 and the expression of their target inflammatory genes. Our data confirm a critical role of HSP90 as a shared underlying molecular target of toxicity by these two distinct vesicants and provide an effective and novel medical countermeasure to suppress vesicant-induced skin injury. SIGNIFICANCE STATEMENT: Development of effective and novel mechanism-based antidotes that can simultaneously block cutaneous toxic manifestations of distinct vesicants is important and urgently needed. Due to difficulties in determining the exact nature of onsite chemical exposure, a potent drug that can suppress widespread cutaneous damage may find great utility. Thus, this study identified HSP90 as a common molecular regulator of cutaneous inflammation and injury by two distinct warfare vesicants, arsenicals and mustards, and HSP90 inhibitors afford significant protection against skin damage.


Assuntos
Arsenicais , Substâncias para a Guerra Química , Gás de Mostarda , Humanos , Animais , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Substâncias para a Guerra Química/toxicidade , Irritantes , Pele , Gás de Mostarda/toxicidade , Arsenicais/metabolismo , Arsenicais/farmacologia
4.
Proc Natl Acad Sci U S A ; 120(49): e2315096120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011564

RESUMO

Hidradenitis suppurativa (HS) is a complex inflammatory skin disease with undefined mechanistic underpinnings. Here, we investigated HS epithelial cells and demonstrated that HS basal progenitors modulate their lineage restriction and give rise to pathogenic keratinocyte clones, resulting in epidermal hyperproliferation and dysregulated inflammation in HS. When comparing to healthy epithelial stem/progenitor cells, in HS, we identified changes in gene signatures that revolve around the mitotic cell cycle, DNA damage response and repair, as well as cell-cell adhesion and chromatin remodeling. By reconstructing cell differentiation trajectory and CellChat modeling, we identified a keratinocyte population specific to HS. This population is marked by S100A7/8/9 and KRT6 family members, triggering IL1, IL10, and complement inflammatory cascades. These signals, along with HS-specific proinflammatory cytokines and chemokines, contribute to the recruitment of certain immune cells during the disease progression. Furthermore, we revealed a previously uncharacterized role of S100A8 in regulating the local chromatin environment of target loci in HS keratinocytes. Through the integration of genomic and epigenomic datasets, we identified genome-wide chromatin rewiring alongside the switch of transcription factors (TFs), which mediated HS transcriptional profiles. Importantly, we identified numerous clinically relevant inflammatory enhancers and their coordinated TFs in HS basal CD49fhigh cells. The disruption of the S100A enhancer using the CRISPR/Cas9-mediated approach or the pharmacological inhibition of the interferon regulatory transcription factor 3 (IRF3) efficiently reduced the production of HS-associated inflammatory regulators. Our study not only uncovers the plasticity of epidermal progenitor cells in HS but also elucidates the epigenetic mechanisms underlying HS pathogenesis.


Assuntos
Hidradenite Supurativa , Humanos , Hidradenite Supurativa/genética , Pele/metabolismo , Epigenômica , Epigênese Genética , Células-Tronco/metabolismo , Cromatina/metabolismo
5.
Int J Pharm ; 647: 123547, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37884214

RESUMO

Lewisite is a chemical warfare agent intended for use in World War and a potential threat to the civilian population due to presence in stockpiles or accidental exposure. Lewisite-mediated skin injury is characterized by acute erythema, pain, and blister formation. N-acetyl cysteine (NAC) is an FDA-approved drug for acetaminophen toxicity, identified as a potential antidote against lewisite. In the present study, we have explored the feasibility of rapid NAC delivery through transdermal route for potentially treating chemical warfare toxicity. NAC is a small, hydrophilic molecule with limited passive delivery through the skin. Using skin microporation with dissolving microneedles significantly enhanced the delivery of NAC into and across dermatomed human skin in our studies. Microporation followed by application of solution (poke-and-solution) resulted in the highest in vitro delivery (509.84 ± 155.04 µg/sq·cm) as compared to poke-and-gel approach (474.91 ± 70.09 µg/sq·cm) and drug-loaded microneedles (226.89 ± 33.41 µg/sq·cm). The lag time for NAC delivery through poke-and-solution approach (0.23 ± 0.04 h) was close to gel application (0.25 ± 0.02 h), with the highest for drug-loaded microneedles (1.27 ± 1.16 h). Thus, we successfully demonstrated the feasibility of rapid NAC delivery using various skin microporation approaches for potential treatment against lewisite-mediated skin toxicity.


Assuntos
Acetilcisteína , Antídotos , Humanos , Administração Cutânea , Pele , Sistemas de Liberação de Medicamentos , Agulhas
6.
Artigo em Inglês | MEDLINE | ID: mdl-37466884

RESUMO

For the past decades, inflammatory signals have been considered a possible key for pharmacological interventions. There are several compounds and/or molecules that have been known as most promising medication against inflammation and its mediated chronic disorders. Inflammasomes could be recognized as a trigger by detrimental stimuli as pathogenic attack and endogenous signals mediated injury inside the cells. In addition, there has been an inflammatory key mechanism involved in cancers including glioblastoma multiforme (GBM). GBM has been considered the foremost aggressive primary brain tumors in adult stage. There is a scattered beam of light on both cellular and molecular links in inflammation and GBM. However, the immune response of GBM has been characterized extensively by macrophages and lymphocytes related to tumors, and some recent investigations have pinpointed the focus of inflammasomes on the progression of GBM. Nevertheless, risk factors linked with GBM are still debatable. In our study, the most considerable compounds and their bonded and/or targeted proteins have depicted the most promising highlights under in silico condition. Our in silico investigations have revealed a powerful pharmacological agents/compound against inflammasome-mediated GBM.

7.
iScience ; 26(6): 106896, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37332597

RESUMO

Hidradenitis suppurativa (HS) is a skin disorder that causes chronic painful inflammation and hyperproliferation, often with the comorbidity of invasive keratoacanthoma (KA). Our research, employing high-resolution immunofluorescence and data science approaches together with confirmatory molecular analysis, has identified that the 5'-cap-dependent protein translation regulatory complex eIF4F is a key factor in the development of HS and is responsible for regulating follicular hyperproliferation. Specifically, eIF4F translational targets, Cyclin D1 and c-MYC, orchestrate the development of HS-associated KA. Although eIF4F and p-eIF4E are contiguous throughout HS lesions, Cyclin D1 and c-MYC have unique spatial localization and functions. The keratin-filled crater of KA is formed by nuclear c-MYC-induced differentiation of epithelial cells, whereas the co-localization of c-MYC and Cyclin D1 provides oncogenic transformation by activating RAS, PI3K, and ERK pathways. In sum, we have revealed a novel mechanism underlying HS pathogenesis of follicular hyperproliferation and the development of HS-associated invasive KA.

8.
Cell Biol Toxicol ; 39(1): 85-110, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35362847

RESUMO

Worldwide, more than 200 million people are estimated to be exposed to unsafe levels of arsenic. Chronic exposure to unsafe levels of groundwater arsenic is responsible for multiple human disorders, including dermal, cardiovascular, neurological, pulmonary, renal, and metabolic conditions. Consumption of rice and seafood (where high levels of arsenic are accumulated) is also responsible for human exposure to arsenic. The toxicity of arsenic compounds varies greatly and may depend on their chemical form, solubility, and concentration. Surprisingly, synthetic organoarsenicals are extremely toxic molecules which created interest in their development as chemical warfare agents (CWAs) during World War I (WWI). Among these CWAs, adamsite, Clark I, Clark II, and lewisite are of critical importance, as stockpiles of these agents still exist worldwide. In addition, unused WWII weaponized arsenicals discarded in water bodies or buried in many parts of the world continue to pose a serious threat to the environment and human health. Metabolic inhibition, oxidative stress, genotoxicity, and epigenetic alterations including micro-RNA-dependent regulation are some of the underlying mechanisms of arsenic toxicity. Mechanistic understanding of the toxicity of organoarsenicals is also critical for the development of effective therapeutic interventions. This review provides comprehensive details and a critical assessment of recently published data on various chemical forms of arsenic, their exposure, and implications on human and environmental health.


Assuntos
Arsênio , Arsenicais , Substâncias para a Guerra Química , Humanos , Arsênio/toxicidade , Arsenicais/efeitos adversos , Arsenicais/metabolismo , Estresse Oxidativo
9.
Ann N Y Acad Sci ; 1515(1): 168-183, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35678766

RESUMO

Arsenical vesicants cause skin inflammation, blistering, and pain. The lack of appropriate animal models causes difficulty in defining their molecular pathogenesis. Here, Ptch1+/- /C57BL/6 mice were employed to investigate the pathobiology of the arsenicals lewisite and phenylarsine oxide (PAO). Following lewisite or PAO challenge (24 h), the skin of animals becomes grayish-white, thick, leathery, and wrinkled with increased bi-fold thickness, Draize score, and necrotic patches. In histopathology, infiltrating leukocytes (macrophages and neutrophils), epidermal-dermal separation, edema, apoptotic cells, and disruption of tight and adherens junction proteins can be visualized. PCR arrays and nanoString analyses showed significant increases in cytokines/chemokines and other proinflammatory mediators. As hair follicles (HFs), which provide an immune-privileged environment, may affect immune cell trafficking and consequent inflammatory responses, we compared the pathogenesis of these chemicals in this model to that in Ptch1+/- /SKH-1 hairless mice. Ptch1+/- /SKH-1 mice have rudimentary, whereas Ptch1+/- /C57BL/6 mice have well-developed HFs. Although no significant differences were observed in qualitative inflammatory responses between the two strains, levels of cytokines/chemokines differed. Importantly, the mechanism of inflammation was identical; both reactive oxygen species induction and consequent activation of unfolded protein response signaling were similar. These data reveal that the acute molecular pathogenesis of arsenicals in these two murine models is similar.


Assuntos
Arsenicais , Substâncias para a Guerra Química , Animais , Substâncias para a Guerra Química/metabolismo , Quimiocinas , Citocinas/metabolismo , Folículo Piloso/metabolismo , Folículo Piloso/patologia , Inflamação/patologia , Irritantes , Camundongos , Camundongos Pelados , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Pele/metabolismo
10.
Bioorg Med Chem Lett ; 64: 128696, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35318165

RESUMO

Arsenicals belong to the class of chemical warfare agents known as vesicants, which are highly reactive, toxic and cause robust inflammatory response. Cutaneous exposure to arsenicals causes a wide range of systemic organ damage, beginning with cutaneous injuries, and later manifest multi-organ damage and death. Thus, the development of suitable antidotes that can effectively block injury following exposure to these agents is of great importance. Bromodomain 4 (BRD4), a member of the bromodomain and extra terminal domain (BET) family, plays crucial role in regulating transcription of inflammatory, proliferation and cell cycle genes. In this context, the development of potent small molecule inhibitors of BRD4 could serve as potential antidotes for arsenicals. Herein, we describe the synthesis and biological evaluation of a series of compounds.


Assuntos
Arsenicais , Anti-Inflamatórios/química , Antídotos/farmacologia , Arsenicais/farmacologia , Arsenicais/uso terapêutico , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo
11.
Inflammation ; 45(3): 1388-1401, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35301634

RESUMO

Hidradenitis suppurativa (HS) is a complex and debilitating inflammatory skin disease for which no effective treatment is available currently. This is partly because of the lack of adequate human or animal models for defining the pathobiology of the disease. Here, we describe the development of air-liquid (A-L) interface, liquid-submersion (L-S), and bioreactor (Bio) ex vivo skin culture models. All three ex vivo platforms were effective for culturing skin samples for up to 14 days. Tissue architecture and integrity remained intact for at least 3 days for healthy skin and 14 days for HS skin. Up to day 3, no significant differences were observed in % early apoptotic cells among all three platforms. However, late apoptotic/necrotic cell death was increased in HS skin at day 3 in A-L and Bio culture. These cultures efficiently support the growth of various cells populations, including keratinocytes and immune cells. Profiling inflammatory gene signatures in HS skin from these ex vivo cultures showed dynamic changes in expression at day 3 and day 14. All three culture platforms were necessary to represent the inflammatory gene status of HS skin at day 0, suggesting that not all gene clusters were identically altered in each culture method. Similarly, cytokine/chemokine profiling of the supernatants from vehicle- and drug-treated ex vivo HS cultures again showed a better prediction of drug efficacy against HS. Overall, development of these three culture systems collectively provides a powerful tool to uncover the pathobiology of HS progression and screen various drugs against HS.


Assuntos
Hidradenite Supurativa , Animais , Citocinas/metabolismo , Hidradenite Supurativa/tratamento farmacológico , Hidradenite Supurativa/patologia , Queratinócitos/metabolismo , Pele/metabolismo , Resultado do Tratamento
12.
Semin Cell Dev Biol ; 128: 120-129, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35131152

RESUMO

Hidradenitis suppurativa (HS) is characterized by deep-seated, highly inflamed, and painful lumps/abscesses, fistulae, and sinus tracts that grow extensively deep in the dermis and are highly immunogenic in nature. In about one-third of the HS patients there is strong evidence for the role of γ-secretase mutations along with dysregulated Notch signaling. However, the contribution of dysregulated Notch signaling in HS pathogenesis in relation to hair follicle alterations and hyper-activation of the immune system remains undefined. A genome-wide association study (GWAS), proteomic data and functional investigations of identified sequence variants in HS pathology are not fully revealing. The disease initiation or progression may involve bacterial infection besides intrinsic functional defects in keratinocytes, which may be key to further exacerbate immune cell infiltration and cytokine production in and around the lesional tissue. The absence of a suitable animal model that could fully recapitulate the pathogenesis of HS is a major impediment for proper understanding the underlying mechanisms and development of effective treatments. The presence of extracellular matrix (ECM) degradation products along with dysregulation in keratinocytes and, dermal fibroblasts ultimately affect immune regulation and are various components of HS pathogenesis. Bacterial infection further exacerbates the complexity of the disease progression. While anti-TNFα therapy shows partial efficacy, treatment to cure HS is absent. Multiple clinical trials targeting various cytokines, complement C5a and ECM products are in progress. This review provides state-of-the-art information on these aspects with a focus on dysregulated keratinocyte and immune cells; and role of ECM, and Keratin functions in this regard.


Assuntos
Hidradenite Supurativa , Animais , Proteínas do Citoesqueleto/metabolismo , Estudo de Associação Genômica Ampla , Hidradenite Supurativa/genética , Hidradenite Supurativa/patologia , Humanos , Queratinas/genética , Queratinas/metabolismo , Proteômica , Transdução de Sinais/genética
13.
Sci Rep ; 12(1): 1313, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079027

RESUMO

Cisplatin (CP) is a well-known anticancer drug used to effectively treat various kinds of solid tumors. CP causes acute kidney injury (AKI) and unfortunately, there is no therapeutic approach in hand to prevent AKI. Several signaling pathways are responsible for inducing AKI which leads to inflammation in proximal convoluted tubule cells in the kidney. Furthermore, the nucleotide-binding oligomerization domain (NOD)-like receptor containing pyrin domain 3 (NLRP3) inflammasome is involved in the CP-induced AKI. In this study, we investigated therapeutic effects of rosmarinic acid (RA) against inflammation-induced AKI. RA was orally administered at the dose of 100 mg/kg for two consecutive days after 24 h of a single injection of CP at the dose of 20 mg/kg administered intraperitoneally in Swiss albino male mice. Treatment of RA inhibited the activation of NLRP3 signaling pathway by blocking the activated caspase-1 and downstream signal molecules such as IL-1ß and IL18. CP activated HMGB1-TLR4/MyD88 axis was also found to be downregulated with the RA treatment. Activation of nuclear factor-κB and elevated protein expression of cyclooxygenase-2 (COX-2) were also found to be downregulated in RA-treated animals. Alteration of early tubular injury biomarker, kidney injury molecule-1 (KIM-1), was found to be subsided in RA-treated mice. RA has been earlier reported for antioxidant and anti-inflammatory properties. Our findings show that blocking a critical step of inflammasome signaling pathway by RA treatment can be a novel and beneficial approach to prevent the CP-induced AKI.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Cinamatos/administração & dosagem , Depsídeos/administração & dosagem , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Injúria Renal Aguda/induzido quimicamente , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Túbulos Renais Proximais/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Resultado do Tratamento , Ácido Rosmarínico
15.
J Invest Dermatol ; 141(4): 742-753.e10, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32971126

RESUMO

Skin squamous cell carcinomas (SCCs) are a major cause of death in patients who have undergone or will undergo organ transplantation. Moreover, these neoplasms cause significant disease and economic burden and diminish patients' life quality. However, no effective treatment or intervention strategies are available. In this study, we investigated the pathologic role of 5'-cap translation, which is regulated by the formation of a ternary initiation factor complex involving eIF4E, eIF4G, and eIF4A1. We detected increased expression of phosphorylated eIF4E, eIF4G, and eIF4A1 in human and murine skin SCCs. The increase in these ternary initiation factor complex proteins was associated with enhanced eIF4E translation targets cyclin D1 and c-Myc. Conversely, small interfering RNA-mediated depletion of eIF4E in human SCC cells (A431 and SCC-13) reduced eIF4G and proteins that regulate the cell cycle and proliferation. Notably, inhibition of Raf/MAPK/extracellular signal-regulated kinase signaling decreased eIF4E and phosphorylated eIF4E accumulation and significantly diminished cell-cycle gene expression and tumor volume of A431-derived xenograft tumors. Furthermore, disrupting the eIF4E with an allosteric inhibitor of eIF4E and eIF4G binding, 4EGI-1, decreased the eIF4E/eIF4G expression and reduced the proliferation. Finally, combined inhibition of the Raf/MAPK/extracellular signal-regulated kinase axis and eIF4E impaired 5'-cap‒dependent translation and abrogated tumor cell proliferation. These data demonstrate that 5'-cap‒dependent translation is a potential therapeutic target for abrogating lethal skin SCCs in patients who have undergone or will undergo organ transplantation.


Assuntos
Carcinoma de Células Escamosas/genética , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , RNA Interferente Pequeno/farmacologia , Neoplasias Cutâneas/genética , Regulação Alostérica/efeitos dos fármacos , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Ciclina D1/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , Fosforilação , Proteínas Proto-Oncogênicas c-myc/genética , Capuzes de RNA/metabolismo , RNA Interferente Pequeno/uso terapêutico , Pele/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Brain Res Bull ; 165: 108-117, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33011197

RESUMO

Amyloid-ß (Aß) accumulation in the brain is a pathological hallmark of Alzheimer's disease (AD). Endoplasmic reticulum (ER) stress has been implicated in aetiology of neurodegenerative disorders. We studied the involvement of ER stress in Aß-induced neuronal degeneration in rat brain to correlate it with cellular and molecular modifications in Aß-induced Alzheimer's like neuropathological process. Aß (1-42) (5 µg) was administered by bilateral intracerebroventricular (icv) injection in the brain of adult male Wistar rats. Acetylcholinesterase (AChE) activity and histological alterations were observed in different brain regions. ER stress-associated proteins- glucose regulated protein-78 (GRP78), eukaryotic translation initiation factor-2α (eIF2α) and growth arrest and DNA damage-inducible protein-153 (GADD153), neuronal marker- microtubule associated protein-2 (MAP-2) and microglial protein- ionized calcium binding adaptor molecule-1 (Iba-1) were measured by western blot. Reduced glutathione (GSH), nitrite level and levels of caspase-12 and caspase-3 were also measured. ER stress inhibitor, salubrinal (1 mg/kg, intraperitoneally, ip) was used to assess the specific role of ER stress. Aß (1-42)-induced increase in AChE activity, GRP78 and GADD protein levels, dephosphorylation of eIF2-α and caspase-12 and caspase-3 levels and decrease in GSH and MAP-2 levels were attenuated by salubrinal. Increase in Iba-1 protein and nitrite levels after Aß (1-42) administration were partially attenuated by salubrinal. Aß (1-42)-induced histological alterations were correlated with findings of ER stress. Results of present study implicate ER stress as a potential molecular mechanism in Aß-induced Alzheimer's like neuropathology which could serve as surrogate biomarker for study of AD progression and efficacy of therapeutic interventions for AD management.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Acetilcolinesterase/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Glutationa/metabolismo , Proteínas de Choque Térmico/metabolismo , Masculino , Neurônios/patologia , Nitritos/metabolismo , Estresse Oxidativo/fisiologia , Fosforilação , Ratos , Ratos Wistar
17.
Ann N Y Acad Sci ; 1480(1): 155-169, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32885420

RESUMO

Lewisite and many other similar arsenicals are warfare vesicants developed and weaponized for use in World Wars I and II. These chemicals, when exposed to the skin and other epithelial tissues, cause rapid severe inflammation and systemic damage. Here, we show that topically applied arsenicals in a murine model produce significant acute kidney injury (AKI), as determined by an increase in the AKI biomarkers NGAL and KIM-1. An increase in reactive oxygen species and ER stress proteins, such as ATF4 and CHOP, correlated with the induction of these AKI biomarkers. Also, TUNEL staining of CHOP-positive renal tubular cells suggests CHOP mediates apoptosis in these cells. A systemic inflammatory response characterized by a significant elevation in inflammatory mediators, such as IL-6, IFN-α, and COX-2, in the kidney could be the underlying cause of AKI. The mechanism of arsenical-mediated inflammation involves activation of AMPK/Nrf2 signaling pathways, which regulate heme oxygenase-1 (HO-1). Indeed, HO-1 induction with cobalt protoporphyrin (CoPP) treatment in arsenical-treated HEK293 cells afforded cytoprotection by attenuating CHOP-associated apoptosis and cytokine mRNA levels. These results demonstrate that topical exposure to arsenicals causes AKI and that HO-1 activation may serve a protective role in this setting.


Assuntos
Injúria Renal Aguda , Apoptose/efeitos dos fármacos , Arsenicais , Substâncias para a Guerra Química/intoxicação , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/prevenção & controle , Animais , Biomarcadores/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Interleucina-6/metabolismo , Camundongos , Camundongos Pelados , Fator 2 Relacionado a NF-E2/metabolismo , Fator de Transcrição CHOP/metabolismo
18.
Proc Natl Acad Sci U S A ; 116(49): 24583-24592, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31732667

RESUMO

The mammalian target of rapamycin (mTOR) pathway, which plays a critical role in regulating cellular growth and metabolism, is aberrantly regulated in the pathogenesis of a variety of neoplasms. Here we demonstrate that dual mTORC1/mTORC2 inhibitors OSI-027 and PP242 cause catastrophic macropinocytosis in rhabdomyosarcoma (RMS) cells and cancers of the skin, breast, lung, and cervix, whereas the effects are much less pronounced in immortalized human keratinocytes. Using RMS as a model, we characterize in detail the mechanism of macropinocytosis induction. Macropinosomes are distinct from endocytic vesicles and autophagosomes in that they are single-membrane bound vacuoles formed by projection, ruffling, and contraction of plasma membranes. They are positive for EEA-1 and LAMP-1 and contain watery fluid but not organelles. The vacuoles then merge and rupture, killing the cells. We confirmed the inhibition of mTORC1/mTORC2 as the underpinning mechanism for macropinocytosis. Exposure to rapamycin, an mTORC1 inhibitor, or mTORC2 knockdown alone had little or reduced effect relative to the combination. We further demonstrate that macropinocytosis depends on MKK4 activated by elevated reactive oxygen species. In a murine xenograft model, OSI-027 reduced RMS tumor growth. Molecular characterization of the residual tumors was consistent with the induction of macropinocytosis. Furthermore, relative to the control xenograft tumors, the residual tumors manifested reduced expression of cell proliferation markers and proteins that drive the epithelial mesenchymal transition. These data indicate a role of mTORC2 in regulating tumor growth by macropinocytosis and suggest that dual inhibitors could help block refractory or recurrent RMS and perhaps other neoplasms and other cancer as well.


Assuntos
Antineoplásicos/farmacologia , Imidazóis/farmacologia , Indóis/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Pinocitose/efeitos dos fármacos , Purinas/farmacologia , Triazinas/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Ciclofosfamida/administração & dosagem , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Imidazóis/administração & dosagem , MAP Quinase Quinase 4/metabolismo , Camundongos Nus , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/patologia , Triazinas/administração & dosagem , Vacúolos/efeitos dos fármacos , Vacúolos/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
PLoS One ; 14(11): e0224162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31693697

RESUMO

BACKGROUND: Type 2 Diabetes Mellitus (T2DM) is characterised by hyperglycemia due to the incidence of insulin resistance. Testosterone supplementation has been shown to have a positive co-relation with improved glycemic control in T2DM males. Clinical studies have reported that Androgen Replacement Therapy (ART) to hypogonadic males with T2DM resulted in improved glycemic control and metabolic parameters, but, these studies did not address in detail how testosterone acted on the key glucose homeostatic organs. METHOD: In this study, we delineate the effect of testosterone supplementation to high-fat diet (HFD) induced T2DM in male C57BL6J mice and the effect of testosterone supplementation on the skeletal muscle insulin responsiveness. We also studied the effect of testosterone on the insulin signaling pathway proteins in C2C12 myocyte cells to validate the in vivo findings. RESULTS: We found that testosterone had a potentiating effect on the skeletal muscle insulin signaling pathway to improve glycaemic control. We demonstrate that, in males, testosterone improves skeletal muscle insulin responsiveness by potentiating the PI3K-AKT pathway. The testosterone treated animals showed significant increase in the skeletal muscle Insulin Receptor (IR), p85 subunit of PI3K, P-GSK3α (Ser-21), and P-AKT (Ser-473) levels as compared to the control animals; but there was no significant change in total AKT and GSK3α. Testosterone supplementation inhibited GSK3α in the myocytes in a PI3K/AKT pathway dependent manner; on the other hand GSK3ß gene expression was reduced in the skeletal muscle upon testosterone supplementation. CONCLUSION: Testosterone increases insulin responsiveness by potentiating insulin signaling in the skeletal muscle cells, which is in contrast to the increased insulin resistance in the liver of testosterone treated T2DM male animals.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Resistência à Insulina , Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Testosterona/administração & dosagem , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Insulina/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Receptor de Insulina/metabolismo
20.
J Environ Pathol Toxicol Oncol ; 38(2): 185-194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679281

RESUMO

In our current study, we synthesized silver nanoparticles (AgNPs) from an aqueous seed extract of Nigella sativa. The seed extract contains phytochemical compounds including phenols, terpenoids, and flavonoids that may act as reducing agents and are able to convert metal ions to metal nanoparticles. The formation of synthesized AgNPs was characterized using UV-visible spectroscopy, Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDX). The efficacy of N-AgNPs against human breast cancer (MCF-7) cells was tested. The synthesized AgNPs displayed dose-dependent cytotoxicity (1-200 µg/mL) against MCF-7 cells. Morphological alterations of the cells also appeared as bright field images. Treatment of synthesized AgNPs altered the expression of Bax and Bcl-2 (apoptotic proteins) and COX-2 (inflammatory marker) in MCF-7 cells. To our knowledge, this is the first report demonstrating that N-AgNPs from Nigella sativa can induce apoptosis in MCF-7 cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas , Nigella sativa/química , Extratos Vegetais/farmacologia , Prata/farmacologia , Neoplasias da Mama/tratamento farmacológico , Humanos , Células MCF-7 , Extratos Vegetais/química , Sementes/química
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