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1.
Int J Mol Sci ; 25(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39337631

RESUMO

Gender and biological sex have distinct impacts on the pathogenesis of type 2 diabetes (T2D). Estrogen deficiency is known to predispose female mice to T2D. In our previous study, we found that a high-fat, high-sucrose diet (HFHSD) induces T2D in male mice through the miR-10b-5p/KLF11/KIT pathway, but not in females, highlighting hormonal disparities in T2D susceptibility. However, the underlying molecular mechanisms of this hormonal protection in females remain elusive. To address this knowledge gap, we utilized ovariectomized, estrogen-deficient female mice, fed them a HFHSD to induce T2D, and investigated the molecular mechanisms involved in estrogen-deficient diabetic female mice, relevant cell lines, and female T2D patients. Initially, female mice fed a HFHSD exhibited a delayed onset of T2D, but ovariectomy-induced estrogen deficiency promptly precipitated T2D without delay. Intriguingly, insulin (INS) was upregulated, while insulin receptor (INSR) and protein kinase B (AKT) were downregulated in these estrogen-deficient diabetic female mice, indicating insulin-resistant T2D. These dysregulations of INS, INSR, and AKT were mediated by a miR-10a/b-5p-NCOR2 axis. Treatment with miR-10a/b-5p effectively alleviated hyperglycemia in estrogen-deficient T2D female mice, while ß-estradiol temporarily reduced hyperglycemia. Consistent with the murine findings, plasma samples from female T2D patients exhibited significant reductions in miR-10a/b-5p, estrogen, and INSR, but increased insulin levels. Our findings suggest that estrogen protects against insulin-resistant T2D in females through miR-10a/b-5p/NCOR2 pathway, indicating the potential therapeutic benefits of miR-10a/b-5p restoration in female T2D management.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , MicroRNAs , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Feminino , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/genética , Resistência à Insulina/genética , Humanos , Insulina/metabolismo , Insulina/sangue , Estrogênios/metabolismo , Estrogênios/deficiência , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Masculino , Ovariectomia
2.
Front Oncol ; 14: 1432286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39324008

RESUMO

Introduction: Renal cell carcinoma (RCC) represents cancer originating from the renal epithelium and accounts for > 90% of cancers in the kidney. Prostate-specific membrane antigen (PSMA) is overexpressed in tumor-associated neovascular endothelial cells of many solid tumors, including metastatic RCC. Although studied in several small clinical studies, PSMA-based imaging and therapy have not been pursued rigorously in preclinical RCC. This study aimed to evaluate the preclinical performance of PSMA-based radiotheranostic agents in a relevant murine model. Methods: A PSMA-overexpressing murine cell line, PSMA+ RENCA, was developed by lentiviral transduction. PSMA-based theranostic agents, 68Ga-L1/177Lu-L1/225Ac-L1, were synthesized in high radiochemical yield and purity following our reported methods. Immunocompetent BALB/c mice were used for flank and orthotopic tumor inoculation. 68Ga-L1 was evaluated in small animal PET/CT imaging in flank and PET/MR imaging in orthotopic models. Cell viability studies were conducted for 177Lu-L1 and 225Ac-L1. Proof-of-concept treatment studies were performed using 225Ac-L1 (0, 37 kBq, 2 kBq × 37 kBq, 1 week apart) using PSMA+ RENCA in the flank model. Results: Cellular uptake of 68Ga-L1, 177Lu-L1, and 225Ac-L1 confirmed the specificity of the agents to PSMA+ RENCA cells rather than to RENCA (wt) cells, which are low in PSMA expression. The uptake in PSMA+ RENCA cells at 1 h for 68Ga-L1 (49.0% incubated dose [ID] ± 3.6%ID/million cells), 177Lu-L1 (22.1%ID ± 0.5%ID)/million cells), and 225Ac-L1 (4.1% ± 0.2% ID)/million cells), respectively, were higher than the RENCA (wt) cells (~ 1%ID-2%ID/million cells). PET/CT images displayed > 7-fold higher accumulation of 68Ga-L1 in PSMA+ RENCA compared to RENCA (wt) in flank implantation at 1 h. A twofold higher accumulation of 68Ga-L1 was observed in orthotopic tumors than in normal kidneys during 1-3 h postinjection. High lung uptake was observed with 68Ga-L1 PET/MR imaging 3 weeks after orthotopic implantation of PSMA+ RENCA due to spontaneous lung metastases. The imaging data were further confirmed by immunohistochemical characterization. 225Ac-L1 (0-37 kBq) displayed a dose-dependent reduction of cell proliferation in the PSMA+ RENCA cells after 48 h incubation; ~ 40% reduction in the cells with treated 37 kBq compared to vehicle (p < 0.001); however, no effect was observed with 177Lu-L1 (0-3700 kBq) up to 144 h postinoculation, suggesting lower efficacy of ß-particle-emitting radiations in cellular studies compared to α-particle-emitting 225Ac-L1. Animals treated with 225Ac-L1 at 1 week posttumor inoculation in flank models displayed significant tumor growth delay (p < 0.03) and longer median survival of 21 days and 24 days for the treatment groups 37 kBq and 2 kBq × 37 kBq, respectively, compared to the vehicle group (12 days). Conclusion: The results suggest that a theranostic strategy targeting PSMA, employing PET and α-emitting radiopharmaceuticals, enabled tumor growth control and enhanced survival in a relevant immunocompetent murine model of RCC. These studies provide the rationale for clinical studies of PSMA-targeted theranostic agents in patients with RCC.

3.
Anal Methods ; 16(36): 6183-6192, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39189797

RESUMO

2D MXenes have been used as electrochemical sensor materials, but their output current signal remains weak in point of care (PoC) settings. To address this issue, here we report a novel MXene-supported cobalt-MOF-based nanocomposite, which is used with a carbon black (CB) ink and 3-D printed as the CoMOF-MXene@CB layered electrode structure for the development of a sensor electrode and a PoC chip for electrochemical detection of blood creatinine with an enhanced current range, specificity, and sensitivity. The limit of detection (LOD) and sensitivity of the fabricated sensor were found to be 0.005 µM and 1.1 µA µM-1 cm-2, which are 44 times lower and 32 times enhanced, respectively, as compared to the existing literature report (LOD 0.22 µM and sensitivity 0.034 µA µM-1) for creatinine sensing in PoC settings. The sensor exhibited an excellent linear sensor response ranging from 10 to 800 µM and good reproducibility, stability, and selectivity with significant accuracy. These characteristics helped the sensor to accurately determine the creatinine levels in real human serum samples.


Assuntos
Cobalto , Creatinina , Técnicas Eletroquímicas , Limite de Detecção , Nanocompostos , Sistemas Automatizados de Assistência Junto ao Leito , Cobalto/química , Cobalto/sangue , Nanocompostos/química , Humanos , Creatinina/sangue , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Estruturas Metalorgânicas/química , Reprodutibilidade dos Testes , Eletrodos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Fuligem/química
4.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396943

RESUMO

microRNAs (miRNAs) are key regulators of both physiological and pathophysiological mechanisms in diabetes and gastrointestinal (GI) dysmotility. Our previous studies have demonstrated the therapeutic potential of miR-10a-5p mimic and miR-10b-5p mimic (miR-10a/b mimics) in rescuing diabetes and GI dysmotility in murine models of diabetes. In this study, we elucidated the safety profile of a long-term treatment with miR-10a/b mimics in diabetic mice. Male C57BL/6 mice were fed a high-fat, high-sucrose diet (HFHSD) to induce diabetes and treated by five subcutaneous injections of miR-10a/b mimics for a 5 month period. We examined the long-term effects of the miRNA mimics on diabetes and GI dysmotility, including an assessment of potential risks for cancer and inflammation in the liver and colon using biomarkers. HFHSD-induced diabetic mice subcutaneously injected with miR-10a/b mimics on a monthly basis for 5 consecutive months exhibited a marked reduction in fasting blood glucose levels with restoration of insulin and significant weight loss, improved glucose and insulin intolerance, and restored GI transit time. In addition, the miR-10a/b mimic-treated diabetic mice showed no indication of risk for cancer development or inflammation induction in the liver, colon, and blood for 5 months post-injections. This longitudinal study demonstrates that miR-10a/b mimics, when subcutaneously administered in diabetic mice, effectively alleviate diabetes and GI dysmotility for 5 months with no discernible risk for cancer or inflammation in the liver and colon. The sustained efficacy and favorable safety profiles position miR-10a/b mimics as promising candidates in miRNA-based therapeutics for diabetes and GI dysmotility.


Assuntos
Diabetes Mellitus Experimental , MicroRNAs , Neoplasias , Masculino , Animais , Camundongos , Diabetes Mellitus Experimental/genética , Estudos Longitudinais , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Inflamação , Fígado , Insulina , Colo
5.
Mol Immunol ; 163: 136-146, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778149

RESUMO

One of the major reasons behind the limited success of vaccine candidates against all forms of leishmaniasis is the inability of parasitic antigens to induce robust cell-mediated immunity and immunological memory. Here we find, for the first time, that the adjuvantation of whole-killed Leishmania vaccine (Leishvacc) with anti-CD200 and anti-CD300a antibodies enhances CD4+ T cells mediated immunity in vaccinated mice and provides protection against wild-type parasites. The antibody adjuvantation, either alone or with a TLR4 agonist monophosphoryl A (MPL-A), induced the production of pro-inflammatory cytokines viz., IFN-γ, TNF-α, and IL-2 by antigen experienced CD4+ T cells, and also enhanced their rate of conversion into their memory phenotypes against Leishvacc antigens. The antibody adjuvanted vaccine also promoted the generation of IgG2a-mediated protective humoral immunity in vaccinated mice. Further, the mice vaccinated with antibodies adjuvanted vaccine showed strong resilience against metacyclic forms of L. donovani parasites as we observed reduced clinical features such as splenomegaly, hepatomegaly, granulomatous tissues in the liver, and parasitic load in their spleen. The findings of this study demonstrate that the anti-CD200 and anti-CD300a antibodies have potential to increase the protective efficacy of the whole-killed Leishmania vaccine, and opens up a new gateway to diversify the roles of immune checkpoints in vaccine development against leishmaniasis.


Assuntos
Leishmania donovani , Leishmania , Vacinas contra Leishmaniose , Leishmaniose Visceral , Leishmaniose , Parasitos , Animais , Camundongos , Vacinas de Produtos Inativados , Adjuvantes Imunológicos/farmacologia , Leishmaniose/prevenção & controle , Camundongos Endogâmicos BALB C , Antígenos de Protozoários
6.
Molecules ; 28(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37630410

RESUMO

Prostate-specific membrane antigen (PSMA)-based low-molecular-weight agents using beta(ß)-particle-emitting radiopharmaceuticals is a new treatment paradigm for patients with metastatic castration-resistant prostate cancer. Although results have been encouraging, there is a need to improve the tumor residence time of current PSMA-based radiotherapeutics. Albumin-binding moieties have been used strategically to enhance the tumor uptake and retention of existing PSMA-based investigational agents. Previously, we developed a series of PSMA-based, ß-particle-emitting, low-molecular-weight compounds. From this series, 177Lu-L1 was selected as the lead agent because of its reduced off-target radiotoxicity in preclinical studies. The ligand L1 contains a PSMA-targeting Lys-Glu urea moiety with an N-bromobenzyl substituent in the ε-amino group of Lys. Here, we structurally modified 177Lu-L1 to improve tumor targeting using two known albumin-binding moieties, 4-(p-iodophenyl) butyric acid moiety (IPBA) and ibuprofen (IBU), and evaluated the effects of linker length and composition. Six structurally related PSMA-targeting ligands (Alb-L1-Alb-L6) were synthesized based on the structure of 177Lu-L1. The ligands were assessed for in vitro binding affinity and were radiolabeled with 177Lu following standard protocols. All 177Lu-labeled analogs were studied in cell uptake and selected cell efficacy studies. In vivo pharmacokinetics were investigated by conducting tissue biodistribution studies for 177Lu-Alb-L2-177Lu-Alb-L6 (2 h, 24 h, 72 h, and 192 h) in male NSG mice bearing human PSMA+ PC3 PIP and PSMA- PC3 flu xenografts. Preliminary therapeutic ratios of the agents were estimated from the area under the curve (AUC0-192h) of the tumors, blood, and kidney uptake values. Compounds were obtained in >98% radiochemical yields and >99% purity. PSMA inhibition constants (Kis) of the ligands were in the ≤10 nM range. The long-linker-based agents, 177Lu-Alb-L4 and 177Lu-Alb-L5, displayed significantly higher tumor uptake and retention (p < 0.001) than the short-linker-bearing 177Lu-Alb-L2 and 177Lu-Alb-L3 and a long polyethylene glycol (PEG) linker-bearing agent, 177Lu-Alb-L6. The area under the curve (AUC0-192h) of the PSMA+ PC3 PIP tumor uptake of 177Lu-Alb-L4 and 177Lu-Alb-L5 were >4-fold higher than 177Lu-Alb-L2, 177Lu-Alb-L3, and 177Lu-Alb-L6, respectively. Also, the PSMA+ PIP tumor uptake (AUC0-192h) of 177Lu-Alb-L2 and 177Lu-Alb-L3 was ~1.5-fold higher than 177Lu-Alb-L6. However, the lowest blood AUC0-192h and kidney AUC0-192h were associated with 177Lu-Alb-L6 from the series. Consequently, 177Lu-Alb-L6 displayed the highest ratios of AUC(tumor)-to-AUC(blood) and AUC(tumor)-to-AUC(kidney) values from the series. Among the other agents, 177Lu-Alb-L4 demonstrated a nearly similar ratio of AUC(tumor)-to-AUC(blood) as 177Lu-Alb-L6. The tumor-to-blood ratio was the dose-limiting therapeutic ratio for all of the compounds. Conclusions: 177Lu-Alb-L4 and 177Lu-Alb-L6 showed high tumor uptake in PSMA+ tumors and tumor-to-blood ratios. The data suggest that linker length and composition can be modulated to generate an optimized therapeutic agent.


Assuntos
Albuminas , Partículas beta , Humanos , Masculino , Animais , Camundongos , Ligantes , Distribuição Tecidual , Ácido Butírico
7.
Semin Nucl Med ; 53(5): 663-686, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37468417

RESUMO

Prostate cancer is a leading cause of cancer death in men worldwide. Among the various treatment options, radiopharmaceutical therapy has shown notable success in metastatic, castration-resistant disease. Radiopharmaceutical therapy is a systemic approach that delivers cytotoxic radiation doses precisely to the malignant tumors and/or tumor microenvironment. Therapeutic radiopharmaceuticals are composed of a therapeutic radionuclide and a high-affinity, tumor-targeting carrier molecule. Therapeutic radionuclides used in preclinical prostate cancer studies are primarily α-, ß--, or Auger-electron-emitting radiometals or radiohalogens. Monoclonal antibodies, antibody-derived fragments, peptides, and small molecules are frequently used as tumor-targeting molecules. Over the years, several important membrane-associated proteases and receptors have been identified, validated, and subsequently used for preclinical radiotherapeutic development for prostate cancer. Prostate-specific membrane antigen (PSMA) is the most well-studied prostate cancer-associated protease in preclinical literature. PSMA-targeting radiotherapeutic agents are being investigated using high-affinity antibody- and small-molecule-based agents for safety and efficacy. Early generations of such agents were developed simply by replacing radionuclides of the imaging agents with therapeutic ones. Later, extensive structure-activity relationship studies were conducted to address the safety and efficacy issues obtained from initial patient data. Recent regulatory approval of the 177Lu-labeled low-molecular-weight agent, 177Lu-PSMA-617, is a significant accomplishment. Current preclinical experiments are focused on the structural modification of 177Lu-PSMA-617 and relevant investigational agents to increase tumor targeting and reduce off-target binding and toxicity in healthy organs. While lutetium-177 (177Lu) remains the most widely used radionuclide, radiolabeled analogs with iodine-131 (128I), yttrium-90 (89Y), copper-67 (67Cu), and terbium-161 (161Tb) have been evaluated as potential alternatives in recent years. In addition, agents carrying the α-particle-emitting radiohalogen, astatine-211 (211At), or radiometals, actinium-225 (225Ac), lead-212 (212Pb), radium-223 (223Ra), and thorium-227 (227Th), have been increasingly investigated in preclinical research. Besides PSMA-based radiotherapeutics, other prominent prostate cancer-related proteases, for example, human kallikrein peptidases (HK2 and HK3), have been explored using monoclonal-antibody-(mAb)-based targeting platforms. Several promising mAbs targeting receptors overexpressed on the different stages of prostate cancer have also been developed for radiopharmaceutical therapy, for example, Delta-like ligand 3 (DLL-3), CD46, and CUB domain-containing protein 1 (CDCP1). Progress is also being made using peptide-based targeting platforms for the gastrin-releasing peptide receptor (GRPR), a well-established membrane-associated receptor expressed in localized and metastatic prostate cancers. Furthermore, mechanism-driven combination therapies appear to be a burgeoning area in the context of preclinical prostate cancer radiotherapeutics. Here, we review the current developments related to the preclinical radiopharmaceutical therapy of prostate cancer. These are summarized in two major topics: (1) therapeutic radionuclides and (2) tumor-targeting approaches using monoclonal antibodies, small molecules, and peptides.


Assuntos
Neoplasias da Próstata , Compostos Radiofarmacêuticos , Masculino , Humanos , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/química , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/tratamento farmacológico , Anticorpos Monoclonais , Microambiente Tumoral , Antígenos de Neoplasias , Moléculas de Adesão Celular
8.
Carbohydr Res ; 529: 108846, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37245419

RESUMO

To imbibe the aim of synthesizing water-soluble and biocompatible motif, a click-inspired piperazine glycoconjugate has been devised up. In this report, we present a focused approach to design and synthesis of versatile sugar-appended triazoles through 'Click Chemistry' along with their pharmacological studies on cyclin-dependent kinases (CDKs) and cell cytotoxicity on cancer cells using in silico and in vitro approaches, respectively. The study has inclusively recognized the galactose- and mannose-derived piperazine conjugates as the promising motifs. The findings suggested that the galactosyl bis-triazolyl piperazine analogue 10b is the most CDK interactive derivative and also possess significant anticancer activity.


Assuntos
Antineoplásicos , Açúcares , Piperazina/farmacologia , Química Click , Glicoconjugados , Galactose , Antineoplásicos/farmacologia
9.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563399

RESUMO

Metalloendopeptidase ADAM-Like Decysin 1 (ADAMDEC1) is an anti-inflammatory peptidase that is almost exclusively expressed in the gastrointestinal (GI) tract. We have recently found abundant and selective expression of Adamdec1 in colonic mucosal PDGFRα+ cells. However, the cellular origin for this gene expression is controversial as it is also known to be expressed in intestinal macrophages. We found that Adamdec1 mRNAs were selectively expressed in colonic mucosal subepithelial PDGFRα+ cells. ADAMDEC1 protein was mainly released from PDGFRα+ cells and accumulated in the mucosal layer lamina propria space near the epithelial basement membrane. PDGFRα+ cells significantly overexpressed Adamdec1 mRNAs and protein in DSS-induced colitis mice. Adamdec1 was predominantly expressed in CD45- PDGFRα+ cells in DSS-induced colitis mice, with only minimal expression in CD45+ CD64+ macrophages. Additionally, overexpression of both ADAMDEC1 mRNA and protein was consistently observed in PDGFRα+ cells, but not in CD64+ macrophages found in human colonic mucosal tissue affected by Crohn's disease. In summary, PDGFRα+ cells selectively express ADAMDEC1, which is localized to the colon mucosa layer. ADAMDEC1 expression significantly increases in DSS-induced colitis affected mice and Crohn's disease affected human tissue, suggesting that this gene can serve as a diagnostic and/or therapeutic target for intestinal inflammation and Crohn's disease.


Assuntos
Proteínas ADAM , Colite , Doença de Crohn , Doenças Inflamatórias Intestinais , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Animais , Biomarcadores , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Colo/citologia , Colo/metabolismo , Doença de Crohn/metabolismo , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo
10.
Int J Mol Sci ; 23(5)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35269876

RESUMO

Following the discovery of nucleic acids by Friedrich Miescher in 1868, DNA and RNA were recognized as the genetic code containing the necessary information for proper cell functioning. In the years following these discoveries, vast knowledge of the seemingly endless roles of RNA have become better understood. Additionally, many new types of RNAs were discovered that seemed to have no coding properties (non-coding RNAs), such as microRNAs (miRNAs). The discovery of these new RNAs created a new avenue for treating various human diseases. However, RNA is relatively unstable and is degraded fairly rapidly once administered; this has led to the development of novel delivery mechanisms, such as nanoparticles to increase stability as well as to prevent off-target effects of these molecules. Current advances in RNA-based therapies have substantial promise in treating and preventing many human diseases and disorders through fixing the pathology instead of merely treating the symptomology similarly to traditional therapeutics. Although many RNA therapeutics have made it to clinical trials, only a few have been FDA approved thus far. Additionally, the results of clinical trials for RNA therapeutics have been ambivalent to date, with some studies demonstrating potent efficacy, whereas others have limited effectiveness and/or toxicity. Momentum is building in the clinic for RNA therapeutics; future clinical care of human diseases will likely comprise promising RNA therapeutics. This review focuses on the current advances of RNA therapeutics and addresses current challenges with their development.


Assuntos
MicroRNAs , Nanopartículas , Ácidos Nucleicos , Humanos , MicroRNAs/genética , Nanopartículas/uso terapêutico , RNA Interferente Pequeno/genética , RNA não Traduzido/genética
11.
Gastroenterology ; 161(2): 608-622.e7, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33895170

RESUMO

BACKGROUND & AIMS: Constipation is commonly associated with diabetes. Serotonin (5-HT), produced predominantly by enterochromaffin (EC) cells via tryptophan hydroxylase 1 (TPH1), is a key modulator of gastrointestinal (GI) motility. However, the role of serotonergic signaling in constipation associated with diabetes is unknown. METHODS: We generated EC cell reporter Tph1-tdTom, EC cell-depleted Tph1-DTA, combined Tph1-tdTom-DTA, and interstitial cell of Cajal (ICC)-specific Kit-GCaMP6 mice. Male mice and surgically ovariectomized female mice were fed a high-fat high-sucrose diet to induce diabetes. The effect of serotonergic signaling on GI motility was studied by examining 5-HT receptor expression in the colon and in vivo GI transit, colonic migrating motor complexes (CMMCs), and calcium imaging in mice treated with either a 5-HT2B receptor (HTR2B) antagonist or agonist. RESULTS: Colonic transit was delayed in males with diabetes, although colonic Tph1+ cell density and 5-HT levels were increased. Colonic transit was not further reduced in diabetic mice by EC cell depletion. The HTR2B protein, predominantly expressed by colonic ICCs, was markedly decreased in the colonic muscles of males and ovariectomized females with diabetes. Ca2+ activity in colonic ICCs was decreased in diabetic males. Treatment with an HTR2B antagonist impaired CMMCs and colonic motility in healthy males, whereas treatment with an HTR2B agonist improved CMMCs and colonic motility in males with diabetes. Colonic transit in ovariectomized females with diabetes was also improved significantly by the HTR2B agonist treatment. CONCLUSIONS: Impaired colonic motility in mice with diabetes was improved by enhancing HTR2B signaling. The HTR2B agonist may provide therapeutic benefits for constipation associated with diabetes.


Assuntos
Colo/efeitos dos fármacos , Constipação Intestinal/prevenção & controle , Complicações do Diabetes/prevenção & controle , Motilidade Gastrointestinal/efeitos dos fármacos , Indóis/farmacologia , Células Intersticiais de Cajal/efeitos dos fármacos , Complexo Mioelétrico Migratório/efeitos dos fármacos , Receptor 5-HT2B de Serotonina/efeitos dos fármacos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Tiofenos/farmacologia , Animais , Sinalização do Cálcio , Colo/metabolismo , Colo/fisiopatologia , Constipação Intestinal/etiologia , Constipação Intestinal/metabolismo , Constipação Intestinal/fisiopatologia , Complicações do Diabetes/metabolismo , Complicações do Diabetes/fisiopatologia , Modelos Animais de Doenças , Feminino , Genes Reporter , Células Intersticiais de Cajal/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovariectomia , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor 5-HT2B de Serotonina/metabolismo , Serotonina/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo
12.
Gastroenterology ; 160(7): 2451-2466.e19, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33662386

RESUMO

BACKGROUND & AIMS: Gastrointestinal (GI) motility is regulated by serotonin (5-hydroxytryptamine [5-HT]), which is primarily produced by enterochromaffin (EC) cells in the GI tract. However, the precise roles of EC cell-derived 5-HT in regulating gastric motility remain a major point of conjecture. Using a novel transgenic mouse line, we investigated the distribution of EC cells and the pathophysiologic roles of 5-HT deficiency in gastric motility in mice and humans. METHODS: We developed an inducible, EC cell-specific Tph1CreERT2/+ mouse, which was used to generate a reporter mouse line, Tph1-tdTom, and an EC cell-depleted line, Tph1-DTA. We examined EC cell distribution, morphology, and subpopulations in reporter mice. GI motility was measured in vivo and ex vivo in EC cell-depleted mice. Additionally, we evaluated 5-HT content in biopsy and plasma specimens from patients with idiopathic gastroparesis (IG). RESULTS: Tph1-tdTom mice showed EC cells that were heterogeneously distributed throughout the GI tract with the greatest abundance in the antrum and proximal colon. Two subpopulations of EC cells were identified in the gut: self-renewal cells located at the base of the crypt and mature cells observed in the villi. Tph1-DTA mice displayed delayed gastric emptying, total GI transit, and colonic transit. These gut motility alterations were reversed by exogenous provision of 5-HT. Patients with IG had a significant reduction of antral EC cell numbers and 5-HT content, which negatively correlated with gastric emptying rate. CONCLUSIONS: The Tph1CreERT2/+ mouse provides a powerful tool to study the functional roles of EC cells in the GI tract. Our findings suggest a new pathophysiologic mechanism of 5-HT deficiency in IG.


Assuntos
Esvaziamento Gástrico/genética , Trânsito Gastrointestinal/genética , Serotonina/deficiência , Animais , Linhagem Celular , Células Enterocromafins/fisiologia , Humanos , Camundongos , Camundongos Transgênicos , Triptofano Hidroxilase/metabolismo
13.
Gastroenterology ; 160(5): 1662-1678.e18, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421511

RESUMO

BACKGROUND & AIMS: Interstitial cells of Cajal (ICCs) and pancreatic ß cells require receptor tyrosine kinase (KIT) to develop and function properly. Degeneration of ICCs is linked to diabetic gastroparesis. The mechanisms linking diabetes and gastroparesis are unclear, but may involve microRNA (miRNA)-mediated post-transcriptional gene silencing in KIT+ cells. METHODS: We performed miRNA-sequencing analysis from isolated ICCs in diabetic mice and plasma from patients with idiopathic and diabetic gastroparesis. miR-10b-5p target genes were identified and validated in mouse and human cell lines. For loss-of-function studies, we used KIT+ cell-restricted mir-10b knockout mice and KIT+ cell depletion mice. For gain-of-function studies, a synthetic miR-10b-5p mimic was injected in multiple diabetic mouse models. We compared the efficacy of miR-10b-5p mimic treatment vs antidiabetic and prokinetic medicines. RESULTS: miR-10b-5p is highly expressed in ICCs from healthy mice, but drastically depleted in ICCs from diabetic mice. A conditional knockout of mir-10b in KIT+ cells or depletion of KIT+ cells in mice leads to degeneration of ß cells and ICCs, resulting in diabetes and gastroparesis. miR-10b-5p targets the transcription factor Krüppel-like factor 11 (KLF11), which negatively regulates KIT expression. The miR-10b-5p mimic or Klf11 small interfering RNAs injected into mir-10b knockout mice, diet-induced diabetic mice, and TALLYHO polygenic diabetic mice rescue the diabetes and gastroparesis phenotype for an extended period of time. Furthermore, the miR-10b-5p mimic is more effective in improving glucose homoeostasis and gastrointestinal motility compared with common antidiabetic and prokinetic medications. CONCLUSIONS: miR-10b-5p is a key regulator in diabetes and gastrointestinal dysmotility via the KLF11-KIT pathway. Restoration of miR-10b-5p may provide therapeutic benefits for these disorders.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/prevenção & controle , Esvaziamento Gástrico , Trânsito Gastrointestinal , Gastroparesia/prevenção & controle , Células Secretoras de Insulina/metabolismo , Células Intersticiais de Cajal/metabolismo , MicroRNAs/metabolismo , Adulto , Idoso , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Feminino , Gastroparesia/genética , Gastroparesia/metabolismo , Gastroparesia/fisiopatologia , Células HEK293 , Humanos , Células Secretoras de Insulina/patologia , Células Intersticiais de Cajal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Pessoa de Meia-Idade , Células NIH 3T3 , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Adulto Jovem
14.
Indian J Gastroenterol ; 40(1): 56-64, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33443640

RESUMO

BACKGROUND: Studies on frequency and risk factors of gastroesophageal reflux disease (GERD) in the rural Indian population are scanty. METHODS: This household survey was undertaken by the trained interviewers in the adult population (≥ 18 years) in four villages in northern India using translated-validated Enhanced Asian Rome III and hospital anxiety and depression questionnaires. RESULTS: Of 2774 subjects, 2019 (72.8%) had no heartburn. Heartburn frequency was as follows: 314 (11.3%) once/week, 143 (5.2%) twice/week, 85 (3.1%) thrice/week, 69 (2.5%) four times/week, 48 (1.7%) five times/week, 18 (0.6%) six times/week, 41 (1.5%) daily, 37 (1.4%) > once daily. A total of 298 (10.7%) had GERD (definition: heartburn > twice/week). Older age (36.5 vs. 35 years), non-Hindu religion (7, 2.4% vs. 30, 1.2%), lower education (127, 42.6% vs. 789, 31.9%), lower socioeconomic class (94, 31.5% vs. 517, 20.9%) and income (below Indian National Rupees [INR] 458; 105, 35.2% vs. 599, 24.2%), non-vegetarian diet (15, 5% vs. 105, 4.2%), intake of tea/coffee (260, 87.2% vs. 1687, 68.1%), carbonated soft drinks (216, 72.5% vs. 1234, 49.8%), and alcohol (48, 16.1% vs. 313, 12.6%), tobacco chewing (116, 38.9% vs. 681, 27.5%), and smoking (105, 35.2% vs. 672, 27.1%) were associated with GERD on univariate analysis. On multivariate analysis, body mass index > 25 kg/m2 (odds ratio [OR] 1.23; 95% CI 0.88-1.71), predominant rice eating (1.13; 0.74-1.74), tobacco chewing and smoking (1.68; 1.24-2.30 and 1.36; 0.99-1.88), and alcohol (1.2; 0.78-1.83) and carbonated soft drinks (2.48; 1.79-3.44) intake were associated with GERD. A total of 122 (41%) had associated functional dyspepsia. Psychological comorbidities were commoner among those with than without GERD. CONCLUSION: In this rural Indian population, 10.7% had GERD and predominant rice eating, tobacco chewing, and carbonated soft drink intake were the risk factors. Psychological comorbidities were common.


Assuntos
Refluxo Gastroesofágico/epidemiologia , População Rural/estatística & dados numéricos , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Bebidas Gaseificadas/efeitos adversos , Bebidas Gaseificadas/estatística & dados numéricos , Estudos Transversais , Dieta/efeitos adversos , Dieta/estatística & dados numéricos , Dispepsia/epidemiologia , Feminino , Refluxo Gastroesofágico/etiologia , Inquéritos Epidemiológicos , Azia/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Oryza/efeitos adversos , Prevalência , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Uso de Tabaco/efeitos adversos , Uso de Tabaco/epidemiologia , Adulto Jovem
15.
RSC Adv ; 11(4): 2512-2545, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35424186

RESUMO

Currently, developments in the field of quantum dots (QDs) have attracted researchers worldwide. A large variety of QDs have been discovered in the few years, which have excellent optoelectronic, antibacterial, magnetic, and other properties. However, ZnO is the single known material that can exist in the quantum state and can hold all the above properties. There is a lot of work going on in this field and we will be shorthanded if we do not accommodate this treasure at one place. This manuscript will prove to be a milestone in this noble cause. Having a tremendous potential, there is a developing enthusiasm toward the application of ZnO QDs in diverse areas. Sol-gel method being the simplest is the widely-favored synthetic method. Synthesis via this method is largely affected by a number of factors such as the reaction temperature, duration of the reaction, type of solvent, pH of the solution, and the precipitating agent. Doping enhances the optical, magnetic, anti-bacterial, anti-microbial, and other properties of ZnO QDs. However, doping elements reside mostly on the surface of the QDs. The presence of doping elements inside the core is still a major challenge for doping techniques. In this review article, we have focused on pure, rare-earth, and transition metal-doped ZnO QD properties, and the various synthetic processes and applications. Quantum confinement effect is present in nearly every aspect of the QDs. The effect of quantum confinement has also been summarized in this manuscript. Furthermore, the doping of rare earth elements and transition metal, synthetic methods for different organic molecule-capped ZnO QDs, mechanisms for reactive oxygen species (ROS) generation, drug delivery system for cancer treatment, and many more application are discussed in this paper.

16.
Am J Cancer Res ; 10(10): 3487-3506, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163285

RESUMO

Breast cancer remains a complex disease resulting in high mortality in women. A subset of cancer stem cell (CSC)-like cells expressing aldehyde dehydrogenase 1 (ALDH1) and SOX2/OCT4 are implicated in aggressive biology of specific subtypes of breast cancer. Targeting these populations in breast tumors remain challenging. We examined xenografts from three poorly studied triple negative (TN) breast cancer cells (MDA-MB-468, HCC70 and HCC1806) as well as HMLEHRASV12 for stem cell (SC)-specific proteins, proliferation pathways and dual-specific phosphatases (DUSPs) by quantitative real-time PCR (qRT-PCR), immunoblot analysis and immunohistochemistry. We found that pERK1/2 remained suppressed in TN xenografts examined at various stages of growth, while the levels of pp38 MAPK and pAKT was upregulated. We found that DUSP was involved in the suppression of pERK1/2, which was MEK1/2 independent. Our in vitro assays, using HMLEHRASV12 xenografts as a positive control, confirmed increased phosphatase activity that specifically influenced pERK1/2 but not pp38MAPK or pJNK levels. Family members of DUSPs examined, showed increase in DUSP9 expression in TN xenografts. Increased DUSP9 expression in xenografts was consistently associated with upregulation of SC-specific proteins, ALDH1 and SOX2/OCT4. HRAS driven HMLEHRASV12 xenografts as well as mammospheres from TN breast cancer cells showed inverse relationship between pERK1/2 and increased expression of DUSP9 and CSC traits. In addition, treatment in vitro, with MEK1/2 inhibitor, PD 98059, reduced pERK1/2 levels and increased DUSP9 and SC-specific proteins. Depletion of subsets of SOX2/OCT4 by fluorescence-activated cell sorting (FACS), as well as pharmacological and genetic reduction of DUSP9 levels influenced ALDH1 and SOX2/OCT4 expression and reduced mammosphere growth in vitro as well as tumor growth in vivo. Collectively our data support the possibility that DUSP9 contributed to stem cell-like cells that could influence TN breast tumor growth. Conclusion: Our study shows that subsets of TN breast cancers with MEK1/2 independent reduced pERK1/2 levels will respond less to MEK1/2 inhibitors, thereby questioning their therapeutic efficacy. Our study also demonstrates context-dependent DUSP9-mediated reduced pERK1/2 levels could influence stem cell-like traits in TN breast tumors. Therefore, targeting DUSP9 could be an attractive target for improved clinical outcome in a subset of basal-like breast cancers.

17.
Int J Biol Macromol ; 151: 394-401, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32084478

RESUMO

The lacuna in the knowledge of immunobiology, especially in visceral infections that are fatal if left untreated, are a major hurdle in getting a vaccine candidate for leishmaniasis. Till date, only a few drugs are available to combat human leishmaniasis and a vaccine candidate either prophylactic or preventive is still awaited. Therefore, identification of host and parasitic factors involved in the regulation of specific immune mechanisms are essentially needed. In this study, we observed that CD200-CD200R immune inhibitory axis regulates host macrophages effectors properties and helps antigen experienced T cells (CD4+CD44+ T cells) to acquire anti-inflammatory cytokines (IL-4, IL-10, TGF-ß, IL-27) producing abilities in an NFkB independent manner. After CD200 blocking the macrophages effectively inhibited proliferation of Leishmania amastigotes and also induced the production of IL-12, IFN-γ, TNF-α and nitric oxide (NOx). Further, the blocking of CD200 signaling also restored macrophages MHC-II expression and helped CD4+CD44+ T cells to produce pro-inflammatory cytokines like IL-2, IL-12 and IFN-γ. The finding of this study suggested the importance of immune inhibitory mechanisms in controlling Leishmania growth and survival and therefore, requires more studies to understand its role in vaccine induced immunity.


Assuntos
Antígenos CD/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Leishmania donovani , Macrófagos/imunologia , Macrófagos/metabolismo , Receptores de Orexina/metabolismo , Animais , Biomarcadores , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Parasita/imunologia , Receptores de Hialuronatos , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , Leishmaniose Visceral/parasitologia , Camundongos , NF-kappa B/metabolismo , Células RAW 264.7 , Transdução de Sinais
18.
Mediators Inflamm ; 2020: 5239419, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33414685

RESUMO

Breast cancer results from a complex interplay of genetics and environment that alters immune and inflammatory systems to promote tumorigenesis. Obesity and cigarette smoking are well-known risk factors associated breast cancer development. Nicotine known to decrease inflammatory signals also modulates immune responses that favor breast cancer development. However, the mechanisms by which nicotine and obesity contribute to breast cancer remain poorly understood. In this study, we examined potential mechanisms by which nicotine (NIC) and high-fat diet (HFD) promote growth of HCC70 and HCC1806 xenografts from African American (AA) triple negative (TN) breast cancer cells. Immunodeficient mice fed on HFD and treated with NIC generated larger HCC70 and HCC1806 tumors when compared to NIC or HFD alone. Increased xenograft growth in the presence of NIC and HFD was accompanied by higher levels of tissue-resident macrophage markers and anti-inflammatory cytokines including IL4, IL13, and IL10. We further validated the involvement of these players by in vitro and ex vivo experiments. We found a proinflammatory milieu with increased expression of IL6 and IL12 in xenografts with HFD. In addition, nicotine or nicotine plus HFD increased a subset of mammary cancer stem cells (MCSCs) and key adipose browning markers CD137 and TMEM26. Interestingly, there was upregulation of stress-induced pp38 MAPK and pERK1/2 in xenografts exposed to HFD alone or nicotine plus HFD. Scratch-wound assay showed marked reduction in proliferation/migration of nicotine and palmitate-treated breast cancer cells with mecamylamine (MEC), a nicotine acetylcholine receptor (nAchR) antagonist. Furthermore, xenograft development in immune-deficient mice, fed HFD plus nicotine, was reduced upon cotreatment with MEC and SB 203580, a pp38MAPK inhibitor. Our study demonstrates the presence of nicotine and HFD in facilitating an anti-inflammatory tumor microenvironment that influences breast tumor growth. This study also shows potential efficacy of combination therapy in obese breast cancer patients who smoke.


Assuntos
Ração Animal , Anti-Inflamatórios/farmacologia , Neoplasias da Mama/induzido quimicamente , Dieta Hiperlipídica , Nicotina/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Imidazóis/farmacologia , Inflamassomos , Inflamação , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/patologia , Mecamilamina/química , Camundongos , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Nicotina/química , Nicotina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piridinas/farmacologia , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
Neurotox Res ; 36(3): 452-462, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31016688

RESUMO

Neuroinflammation plays an important role in the progression of Parkinson's disease (PD) and hence may represent a target for treatment. The drugs used currently for PD only provide symptomatic relief and have adverse effects in addition to their inability in preventing degeneration of neurons. Flavonoids show potent antioxidant and anti-inflammatory activities which is very valuable for the health of human beings. Thus, in the present study, we have tried to explore the anti-inflammatory activity of orally given ursolic acid (UA) (25 mg/kg bwt), a pentacyclic triterpenoid in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mouse model. Significant severe oxidative stress and biochemical alterations have been seen in Parkinsonian mice after MPTP intoxication. Whereas, UA administration has significantly rescued the harmful consequence of MPTP intoxication. Ionized calcium-binding adaptor molecule 1 (Iba1), tumor necrosis factor-alpha (TNF-α), and nuclear transcription factor-κB (NF-κB) were seen to be altered in the substantia nigra pars compacta (SNpc) of MPTP-intoxicated mice through immunohistochemical studies. The changes in the expression level of these parameters primarily suggest increased inflammatory responses in MPTP-intoxicated mice as compared with the control. However, UA have significantly reduced these inflammatory parameters (Iba1 and TNF-α) along with transcription factor NF-κB, which regulates these inflammatory parameters and thus have inhibited MPTP-induced neuroinflammation. The immunoreactivity of tyrosine hydroxylase (TH) was considerably increased by UA treatment in the SNpc of Parkinsonian mice. The neuroinflammation and neurodegeneration along with impairments in biochemical and behavioral parameters were found to be reversed on treatment with UA. Thus, UA has shown potent anti-inflammatory activity by preventing the degeneration of dopaminergic neurons from MPTP-induced Parkinsonian mice.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antiparkinsonianos/uso terapêutico , Transtornos Parkinsonianos/tratamento farmacológico , Triterpenos/uso terapêutico , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catalase/metabolismo , Imunofluorescência , Glutationa/metabolismo , Inflamação/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Nitritos/metabolismo , Transtornos Parkinsonianos/induzido quimicamente , Desempenho Psicomotor , Reação em Cadeia da Polimerase em Tempo Real , Teste de Desempenho do Rota-Rod , Ácido Ursólico
20.
Front Microbiol ; 10: 669, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019496

RESUMO

Klebsiella pneumoniae is a human pathogen, capable of forming biofilms on abiotic and biotic surfaces. The limitations of the therapeutic options against Klebsiella pneumoniae is actually due to its innate capabilities to form biofilm and harboring determinants of multidrug resistance. We utilized a newer approach for classification of biofilm producing Klebsiella pneumoniae isolates and subsequently we evaluated the chemistry of its slime, more accurately its biofilm. We extracted and determined the amount of polysaccharides and proteins from representative bacterial biofilms. The spatial distribution of sugars and proteins were then investigated in the biofilm matrix using confocal laser scanning microscopy (CLSM). Thereafter, the extracted matrix components were subjected to sophisticated analysis incorporating Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, one-dimensional gel-based electrophoresis (SDS-PAGE), high performance liquid chromatography (HPLC), and MALDI MS/MS analysis. Besides, the quantification of its total proteins, total sugars, uronates, total acetyl content was also done. Results suggest sugars are not the only/major constituent of its biofilms. The proteins were harvested and subjected to SDS-PAGE which revealed various common and unique protein bands. The common band was excised and analyzed by HPLC. MALDI MS/MS results of this common protein band indicated the presence of different proteins within the biofilm. The 55 different proteins were identified including both cytosolic and membrane proteins. About 22 proteins were related to protein synthesis and processing while 15 proteins were identified related to virulence. Similarly, proteins related to energy and metabolism were 8 and those related to capsule and cell wall synthesis were 4. These results will improve our understanding of Klebsiella biofilm composition and will further help us design better strategies for controlling its biofilm such as techniques focused on weakening/targeting certain portions of the slime which is the most common building block of the biofilm matrix.

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