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1.
Environ Technol ; : 1-15, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623591

RESUMO

Efficient recycling of resources forms the cornerstone of sustainable development. Among multiple options in stock for waste recycling, vermicomposting technology is regarded as a futuristic strategy, being tested in every part of the globe due to easy accessibility. Hence, a bibliometric study was planned to set a sight on global scientific trends encompassing vermicomposting research in last three decades. The data were retrieved from Google Scholar, Scopus and PubMed. Publications from different search engines were filtered out and 2064 unique documents were collected and illustrated in MS Excel and Vos-viewer. Inferences were drawn on significant aspects, such as publication growth trend, journal analysis and co-occurrence of keywords. The study revealed that the number of publications increased from 3 in 1992 to 166 in 2021. The number of citations also increased and peaked at 4314 in 2015. Following this, we clustered keywords using principle component analysis and worked out links between domains of vermicomposting. Vermicomposting conjoined to words substrate manipulation, quality improvement, heavy metal adsorption, and yield parameters. This implies that vermicompost is being explored for many alternate uses in addition to its use as a fertiliser. We concluded that vermicomposting is one of the promising technologies for waste recycling. It modulates plant growth and subdues stress in plants. Additionally, being an efficient adsorbent, it serves bioremediation of contaminated sites. Therefore, the future of this technology lies in synthesising nano-formulations, integrating into biosensor technology, simulating for predicting timelines under different conditions and making efforts to improve their adsorption.

2.
PeerJ ; 11: e15993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780386

RESUMO

Soil microbial activity (SMA) is vital concerning carbon cycling, and its functioning is recognized as the primary factor in modifying soil carbon storage potential. The composition of the microbial community (MC) is significant in sustaining environmental services because the structure and activity of MC also influence nutrient turnover, distribution, and the breakdown rate of soil organic matter. SMA is an essential predictor of soil quality alterations, and microbiome responsiveness is imperative in addressing the escalating sustainability concerns in the Himalayan ecosystem. This study was conducted to evaluate the response of soil microbial and enzyme activities to land conversions in the Northwestern Himalayas (NWH), India. Soil samples were collected from five land use systems (LUSs), including forest, pasture, apple, saffron, and paddy-oilseed, up to a depth of 90 cm. The results revealed a significant difference (p < 0.05) in terms of dehydrogenase (9.97-11.83 TPF µg g-1 day-1), acid phosphatase (22.40-48.43 µg P-NP g-1 h-1), alkaline phosphatase (43.50-61.35 µg P-NP g-1 h-1), arylsulphatase (36.33-48.12 µg P-NP g-1 h-1), fluorescein diacetate hydrolase (12.18-21.59 µg g-1 h-1), bacterial count (67.67-123.33 CFU × 106 g-1), fungal count (19.33-67.00 CFU × 105 g-1), and actinomycetes count (12.00-42.33 CFU × 104 g-1), with the highest and lowest levels in forest soils and paddy-oilseed soils, respectively. Soil enzyme activities and microbial counts followed a pattern: forest > pasture > apple > saffron > paddy-oilseed at all three depths. Paddy-oilseed soils exhibited up to 35% lower enzyme activities than forest soils, implying that land conversion facilitates the depletion of microbiome diversity from surface soils. Additionally, reductions of 49.80% and 62.91% were observed in enzyme activity and microbial counts, respectively, with soil depth (from 0-30 to 60-90 cm). Moreover, the relationship analysis (principal component analysis and correlation) revealed a high and significant (p = 0.05) association between soil microbial and enzyme activities and physicochemical attributes. These results suggest that land conversions need to be restricted to prevent microbiome depletion, reduce the deterioration of natural resources, and ensure the sustainability of soil health.


Assuntos
Ciclo do Carbono , Carbono , Ecossistema , Microbiologia do Solo , Solo , Carbono/análise , Florestas , Solo/química , Enzimas , Índia
3.
PeerJ ; 11: e15266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304860

RESUMO

Current study was conducted to evaluate the effect of important land uses and soil depth on soil organic carbon pools viz. total organic carbon, Walkley and black carbon, labile organic carbon, particulate organic carbon, microbial biomass carbon and carbon management index (CMI) in the north Western Himalayas, India. Soil samples from five different land uses viz. forest, pasture, apple, saffron and paddy-oilseed were collected up to a depth of 1 m (0-30, 30-60, 60-90 cm). The results revealed that regardless of soil depth, all the carbon pools differed significantly (p < 0.05) among studied land use systems with maximum values observed under forest soils and lowest under paddy-oilseed soils. Further, upon evaluating the impact of soil depth, a significant (p < 0.05) decline and variation in all the carbon pools was observed with maximum values recorded in surface (0-30 cm) soils and least in sub-surface (60-90 cm) layers. CMI was higher in forest soils and lowest in paddy-oilseed. From regression analysis, a positive significant association (high R-squared values) between CMI and soil organic carbon pools was also observed at all three depths. Therefore, land use changes and soil depth had a significant impact on soil organic carbon pools and eventually on CMI, which is used as deterioration indicator or soil carbon rehabilitation that influences the universal goal of sustainability in the long run.


Assuntos
Carbono , Solo , Biomassa
4.
Indian J Public Health ; 66(Supplement): S41-S44, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36412472

RESUMO

Background: Diabetes has a negative impact on patient's quality of life (QoL). Comorbidities and polypharmacy further worsen their QoL. Thus, in addition to glycemic control, assessment of QoL is also gaining importance. Objective: The objective of this study was to evaluate QoL in patients of type 2 diabetes mellitus (T2DM) with hypertension after add-on empagliflozin to triple drug therapy (metformin, teneligliptin, and glimepiride). Materials and Methods: A prospective research was done on T2DM patients with hypertension, who visited a tertiary care referral institute's endocrine outpatient clinic. For 3 months, empagliflozin, 25 mg once daily, was administered as an add-on treatment with metformin, teneligliptin, and glimepiride. In addition to clinical assessment, an Urdu-translated QoL instrument for Indian diabetes patients was used to conduct QoL study. The QoL outcomes prior to empagliflozin add-on were compared with those obtained at the conclusion of the 3 months of treatment. Results: Empagliflozin as an add-on therapy significantly improved various aspects of QoL like role limitation due to physical health, physical endurance, general health, symptom botherness, financial worries, emotional/mental health, and diet satisfaction (P < 0.001). It also improved glycemic and blood pressure parameters significantly. Conclusion: QoL is an essential measure with respect to patient-centered treatment approach. Empagliflozin, as an add-on medication, improved QoL, glycemic parameters and blood pressure in T2DM patients with hypertension. It can be recommended as an add-on, but more research with a larger sample size is required.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Metformina , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Qualidade de Vida , Estudos Prospectivos , Hipoglicemiantes/uso terapêutico , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/uso terapêutico , Quimioterapia Combinada , Método Duplo-Cego , Índia , Metformina/efeitos adversos , Glicemia , Hipertensão/tratamento farmacológico
5.
J Environ Manage ; 320: 115811, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36056479

RESUMO

The Himalayan ecosystem is critical for ecological security and environmental sustainability. However, continuous deforestation is posing a serious threat to Himalayan sustainability. Changing land-use systems exert a tenacious impact on soil carbon (C) dynamics and regulate C emissions from Himalayan ecosystem. Therefore, this study was conducted to determine the changes in different C pools and associated soil properties under diverse land-use systems, viz. natural forest, natural grassland, maize field converted from the forest, plantation, and paddy field of temperate Himalaya in the surface (0-20 cm) and subsurface (20-40 cm) soils. The highest total organic carbon (24.24 g kg-1) and Walkley-black carbon contents (18.23 g kg-1), total organic carbon (45.88 Mg ha-1), and Walkley-black carbon stocks (34.50 Mg ha-1) were recorded in natural forest in surface soil (0-20 cm depth), while soil under paddy field had least total organic carbon (36.45 Mg ha-1) and Walkley-black carbon stocks (27.40 Mg ha-1) in surface soil (0-20 cm depth). The conversion of natural forest into paddy land results in 47.36% C losses. Among the cultivated land-use system, minimum C losses (29.0%) from different pools over natural forest system were reported under maize-filed converted from forest system. Land conversion causes more C losses (21.0%) in surface soil (0-20 cm depth) as compared to subsurface soil. Furthermore, conversion of forest land into paddy fields increased soil pH by 5.9% and reduced total nitrogen contents and microbial population by 28.0% and 7.0%, respectively. However, the intensity of total nitrogen and microbial population reduction was the lowest under maize fields converted from the forest system. The study suggested that the conversion of natural forest to agricultural land must be discouraged in the temperate Himalayan region. However, to feed the growing population, converted forest land can be brought under conservation effective maize-based systems to reduce C loss from the intensive land use and contribute to soil quality improvements and climate change mitigation.


Assuntos
Carbono , Ecossistema , Agricultura , Carbono/análise , Florestas , Índia , Nitrogênio/análise , Solo/química , Zea mays
6.
Breast Cancer Res ; 24(1): 48, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836253

RESUMO

BACKGROUND: A pro-oxidant enzyme, NADPH oxidase 4 (Nox4) has been reported to be a critical downstream effector of TGFß-induced myofibroblast transformation during fibrosis. While there are a small number of studies suggesting an oncogenic role of Nox4 derived from activated fibroblasts, direct evidence linking this pro-oxidant to the tumor-supporting CAF phenotype and the mechanisms involved are lacking, particularly in breast cancer. METHODS: We targeted Nox4 in breast patient-derived CAFs via siRNA-mediated knockdown or administration of a pharmaceutical inhibitor (GKT137831). We also determine primary tumor growth and metastasis of implanted tumor cells using a stable Nox4-/- syngeneic mouse model. Autophagic flux of CAFs was assessed using a tandem fluorescent-tagged ptfl-LC3 plasmid via confocal microscopy analysis and determination of the expression level of autophagy markers (beclin-1 and LC3B). Nox4 overexpressing CAFs depend on the Nrf2 (nuclear factor-erythroid factor 2-related factor 2) pathway for survival. We then determined the dependency of Nox4-overexpressing CAFs on the Nrf2-mediated adaptive stress response pathway for survival. Furthermore, we investigated the involvement of Birc5 on CAF phenotype (viability and collagen contraction activity) as well as the expression level of CAF markers, FAP and αSMA. CONCLUSIONS: We found that deletion of stroma Nox4 and pharmaceutically targeting its activity with GKT137831 significantly inhibited orthotopic tumor growth and metastasis of implanted E0771 and 4T1 murine mammary carcinoma cell lines in mice. More importantly, we found a significant upregulation of Nox4 expression in CAFs isolated from human breast tumors versus normal mammary fibroblasts (RMFs). Our in situ RNA hybridization analysis for Nox4 transcription on a human breast tumor microarray further support a role of this pro-oxidant in the stroma of breast carcinomas. In addition, we found that Nox4 promotes autophagy in CAFs. Moreover, we found that Nox4 promoted survival of CAFs via activation of Nrf2, a master regulator of oxidative stress response. We have further shown Birc5 is involved as a downstream modulator of Nrf2-mediated pro-survival phenotype. Together these studies indicate a role of redox signaling via the Nox4-Nrf2 pathway in tumorigenesis and metastasis of breast cancer cells by promoting autophagy and survival of CAFs.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Animais , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Feminino , Fibroblastos/metabolismo , Humanos , Camundongos , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Survivina/metabolismo , Regulação para Cima
7.
Mol Biol Rep ; 49(6): 5229-5240, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34387804

RESUMO

BACKGROUND: Sea buckthorn (Hippophae) is in the focus of interest mainly for its positive effects on health of both human and animal organisms. Due to the similarities in vegetative morphology, Hippophae species are often misidentified. Therefore, current study was focused on ITS based sequence characterization of sea buckthorn species and comparative biochemical evaluation for its antioxidant properties. METHODS AND RESULTS: DNA was extracted from leaf samples. Primer pairs K-Lab-SeaBukRhm-ITS1F1- K-Lab-SeaBukRhm-ITS1R1 and K-LabSeaBukTib- ITSF1- K-LabSeaBukTib-ITSR1 were used for PCR amplification. The purified PCR products were outsourced for sequencing. Phylogenetic tree was constructed based on neighbor-joining (NJ) method. Moreover, comparison of antioxidant potential of leaves of two sea buckthorn species (Hippophae rhamnoides and Hippophae tibetana) collected from different regions of Ladakh viz., Stakna, Nubra, DRDO Leh and Zanskar was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3- ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), and Total antioxidant capacity (TAC) by phosphomolybdenum assays. The present investigation led to the differentiation of two sea buckthorn species viz., H. rhamnoides and H. tibetana based on Internal Transcribed Spacer (ITS) region. Moreover, significant variation was observed in antioxidant potential of leaf extracts collected from different regions. CONCLUSIONS: Primary ITS sequence analysis was found to be powerful tool for identification and genetic diversity studies in sea buckthorn. Leaves of sea buckthorn have pronounced antioxidant properties and can be used in food, neutraceuticals and pharmaceutical industries etc. The current study will pave the way to discover small bioactive molecules responsible for antioxidant and anticancer properties in sea buckthorn.


Assuntos
Hippophae , Animais , Antioxidantes/análise , Frutas/química , Variação Genética , Hippophae/química , Hippophae/genética , Filogenia , Extratos Vegetais/química
8.
Foods ; 12(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36613387

RESUMO

Apricot powder was developed through spray drying using gum arabic as an encapsulating material at a concentration of 19%. Inlet air temperature, feed total soluble solids (TSS), feed flow rate, and atomization speed were 190 °C, 23.0 °C, 300.05 mL/h, and 17,433 rpm, respectively. This study was therefore conducted to investigate the influence of anticaking agents (tricalcium phosphate and silicon dioxide) and storage conditions (ambient and accelerated) on physicochemical, micrometric, and thermal characteristics of spray-dried apricot powder (SDAP) packaged in aluminum laminates. Both tricalcium phosphate (TCP) and silicon dioxide (SiO2) improved the shelf life and quality of SDAP, with TCP being more effective, since a lower increase in water activity (aw), moisture content, degree of caking, hygroscopicity, and rehydration time was observed in TCP-treated samples followed by SiO2-treated samples than the control. Furthermore, flowability, glass transition temperature (Tg), and sticky-point temperature (Ts) of SDAP tended to decrease in a significant manner (p < 0.05) under both storage conditions. However, the rate of decrease was higher during accelerated storage. The water activity of treated samples under ambient conditions did not exceed 0.60 and had a total plate count within the permissible range of 40,000 CFU/g, indicating shelf stability of the powder. The predicted shelf life of powder obtained from the Guggenheim−Anderson−de Boer (GAB) model and experimental values were very similar, with TCP-treated samples having a predicted shelf life of 157 days and 77 days under ambient and accelerated storage conditions, respectively. However, the respective experimental shelf life under the same conditions was 150 and 75 days, respectively. Similarly, the predicted shelf life of SiO2-treated samples under ambient and accelerated storage was 137 and 39 days, respectively, whereas the experimental values were 148 and 47 days, respectively. In conclusion, TCP proved more effective than SiO2 at preserving shelf life by preventing moisture ingress.

9.
Radiat Res ; 195(2): 128-139, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33264413

RESUMO

Novel synthetic compounds, known as manganese porphyrins (MnPs), have been designed to shift the redox status of both normal cells and cancer cells. When MnPs are coupled with cancer therapies, such as radiation, they have been shown to sensitize tumor cells to treatment and protect normal tissues from damage through the modulation of the redox status of various tissue types. Until now, our preclinical studies have focused on local effects of MnPs and radiation; however, we recognize that successful outcomes for cancer patients involve control of tumor cells throughout the body. In this study, using murine orthotopic mammary tumor models, we investigated how MnPs and radiation influence the development of distant metastasis. We hypothesized that the combination of MnP (MnP/RT), such as MnTnBuOE-2-PyP5+ and radiation treatment (RT) would increase local tumor control via a shift in the intratumoral redox environment, leading to subsequent downregulation of HIF-1 in the primary tumor. Secondarily, we hypothesized that these primary tumor treatment effects would result in a reduction in pulmonary metastatic burden. Balb/c mice with orthotopic 4T1 mammary carcinomas were treated with saline, MnP, RT or MnP/RT. We found MnP/RT did extend local tumor growth delay and overall survival compared to controls and was associated with increased intratumoral oxidative stress. However, the primary tumor growth delay observed with MnP/RT was not associated with a reduced pulmonary metastatic burden. Future directions to investigate the effects of MnP/RT on the development of distant metastasis may include modifications to the radiation dose, the experimental timeline or using a murine mammary carcinoma cell line with a less aggressive metastatic behavior. Clinical trials are underway to investigate the clinical utility of MnTnBuOE-2-PyP5+ for patients undergoing radiotherapy for various tumor types. The promising preclinical data from this study, as well as others, provides support that MnP/RT has the potential to improve local tumor control for these patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Carcinoma/radioterapia , Metaloporfirinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Animais , Neoplasias da Mama/patologia , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Terapia Combinada , Feminino , Humanos , Manganês/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Porfirinas/farmacologia
10.
Free Radic Biol Med ; 147: 48-60, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31863907

RESUMO

Tumor associated macrophages (TAM) enhance the aggressiveness of breast cancer via promoting cancer cell growth, metastasis, and suppression of the patient's immune system. These TAMs are polarized in breast cancer with features more closely resembling the pro-tumorigenic and immunosuppressive M2 type rather than the anti-tumor and pro-inflammatory M1 type. The goal of our study was to examine primary human monocyte-derived M1 and M2 macrophages for key redox differences and determine sensitivities of these macrophages to the redox-active drug, MnTE-2-PyP5+. This compound reduced levels of M2 markers and inhibited their ability to promote cancer cell growth and suppress T cell activation. The surface levels of the T cell suppressing molecule, PD-L2, were reduced by MnTE-2-PyP5+ in a dose-dependent manner. This study also examined key differences in ROS generation and scavenging between M1 and M2 macrophages. Our results indicate that M2 macrophages have lower levels of reactive oxygen species (ROS) and lower production of extracellular hydrogen peroxide compared to the M1 macrophages. These differences are due in part to reduced expression levels of pro-oxidants, Nox2, Nox5, and the non-enzymatic members of the Nox complex, p22phox and p47phox, as well as higher levels of antioxidant enzymes, Cu/ZnSOD, Gpx1, and catalase. More importantly, we found that despite having lower ROS levels, M2 macrophages require ROS for proper polarization, as addition of hydrogen peroxide increased M2 markers. These TAM-like macrophages are also more sensitive to the ROS modulator and a pan-Nox inhibitor. Both MnTE-2-PyP5+ and DPI inhibited expression levels of M2 marker genes. We have further shown that this inhibition was partly mediated through a decrease in Stat3 activation during IL4-induced M2 polarization. Overall, this study reveals key redox differences between M1 and M2 primary human macrophages and that redox-active drugs can be used to inhibit the pro-tumor and immunosuppressive phenotype of TAM-like M2 macrophages. This study also provides rationale for combining MnTE-2-PyP5+ with immunotherapies.


Assuntos
Ativação de Macrófagos , Macrófagos , Humanos , Macrófagos/metabolismo , Monócitos/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética
11.
Oncotarget ; 8(64): 107390-107408, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29296173

RESUMO

We have previously shown tumor suppressive effects of extracellular superoxide dismutase, EcSOD in breast cancer cells. In this study, an RTK signaling array revealed an inhibitory effect of EcSOD on c-Met phosphorylation and its downstream kinase c-Abl in MDA-MB231 cells. Moreover, an extracellular protein array showed that thrombospondin 1 (TSP-1), a scavenger of the c-Met ligand, hepatocyte growth factor (HGF) is significantly up-regulated in EcSOD overexpressing cells (Ec.20). We further determined the effects of EcSOD on HGF/c-Met-mediated cancer-fibroblast interactions by co-culturing normal fibroblasts (RMF) or RMF which overexpresses HGF (RMF-HGF) with MDA-MB231 cells. We observed that while RMF-HGF significantly promoted Matrigel growth of MDA-MB231, overexpression of EcSOD inhibited the HGF-stimulated growth. Similarly, a SOD mimetic, MnTE-2-PyP, inhibited HGF-induced growth and invasion of MDA-MB231. In addition, a long-term heterotypic co-culture study not only showed that Ec.20 cells are resistant to RMF-HGF-induced invasive stimulation but RMF-HGF that were co-cultured with Ec.20 cells showed an attenuated phenotype, suggesting an oxidative-mediated reciprocal interaction between the two cell types. In addition, we demonstrated that RMF-HGF showed an up-regulation of an ROS-generating enzyme, NADPH oxidase 4 (Nox4). Targeting this pro-oxidant significantly suppressed the activated phenotype of RMF-HGF in a collagen contraction assay, suggesting that RMF-HGF contributes to the oxidative tumor microenvironment. We have further shown that scavenging ROS with EcSOD significantly inhibited RMF-HGF-stimulated orthotopic tumor growth of MDA-MB231. This study suggests the loss of EcSOD in breast cancer plays a pivotal role in promoting the HGF/c-Met-mediated cancer-fibroblast interactions.

12.
Mol Endocrinol ; 29(11): 1594-607, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26378466

RESUMO

Loss of pancreas ß-cell function is the precipitating factor in all forms of diabetes. Cell replacement therapies, such as islet transplantation, remain the best hope for a cure; however, widespread implementation of this method is hampered by availability of donor tissue. Thus, strategies that expand functional ß-cell mass are crucial for widespread usage in diabetes cell replacement therapy. Here, we investigate the regulation of the Hippo-target protein, Yes-associated protein (Yap), during development of the endocrine pancreas and its function after reactivation in human cadaveric islets. Our results demonstrate that Yap expression is extinguished at the mRNA level after neurogenin-3-dependent specification of the pancreas endocrine lineage, correlating with proliferation decreases in these cells. Interestingly, when a constitutively active form of Yap was expressed in human cadaver islets robust increases in proliferation were noted within insulin-producing ß-cells. Importantly, proliferation in these cells occurs without negatively affecting ß-cell differentiation or functional status. Finally, we show that the proproliferative mammalian target of rapamycin pathway is activated after Yap expression, providing at least one explanation for the observed increases in ß-cell proliferation. Together, these results provide a foundation for manipulating Yap activity as a novel approach to expand functional islet mass for diabetes regenerative therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Diabetes Mellitus/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/embriologia , Fosfoproteínas/genética , Aciltransferases , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Ciclo Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Diabetes Mellitus/patologia , Via de Sinalização Hippo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Ilhotas Pancreáticas/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , Serina-Treonina Quinase 3 , Transdução de Sinais , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
13.
Endocr J ; 62(4): 379-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25739404

RESUMO

Agents that stimulate human pancreatic beta cell proliferation are needed to improve diabetes mellitus treatment. Recently, a small molecule, WS6, was observed to stimulate human beta cell proliferation. However, little is known about its other effects on human islets. To better understand the role of WS6 as a possible beta cell regenerative therapy, we carried out in-depth phenotypic analysis of WS6-treated human islets, exploring its effects on non-beta cell proliferation, beta cell differentiation, and islet cell viability. WS6 not only stimulated beta cell proliferation in cultured human islets (in agreement with previous reports), but also human alpha cell proliferation, indicating that WS6 is not a beta cell-specific mitogen. WS6 did not change the proportion of insulin-positive beta cells or the expression of beta cell-specific transcription factors, suggesting that WS6 does not alter beta cell differentiation, and WS6 had no effect on human islet cell apoptosis or viability. In conclusion, WS6 stimulates proliferation of both human beta and alpha cells while maintaining cellular viability and the beta cell differentiated phenotype. These findings expand the literature on WS6 and support the suggestion that WS6 may help increase human islet mass needed for successful treatment of diabetes.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Mitógenos/farmacologia , Compostos de Fenilureia/farmacologia , Adulto , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Células Secretoras de Glucagon/fisiologia , Humanos , Células Secretoras de Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
14.
J Biol Chem ; 290(10): 6071-85, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25548282

RESUMO

Autophagy, a cellular recycling process responsible for turnover of cytoplasmic contents, is critical for maintenance of health. Defects in this process have been linked to diabetes. Diabetes-associated glucotoxicity/lipotoxicity contribute to impaired ß-cell function and have been implicated as contributing factors to this disease. We tested the hypothesis that these two conditions affect ß-cell function by modulating autophagy. We report that exposure of ß-cell lines and human pancreatic islets to high levels of glucose and lipids blocks autophagic flux and leads to apoptotic cell death. EM analysis showed accumulation of autophagy intermediates (autophagosomes), with abundant engulfed cargo in palmitic acid (PA)- or glucose-treated cells, indicating suppressed autophagic turnover. EM studies also showed accumulation of damaged mitochondria, endoplasmic reticulum distention, and vacuolar changes in PA-treated cells. Pulse-chase experiments indicated decreased protein turnover in ß-cells treated with PA/glucose. Expression of mTORC1, an inhibitor of autophagy, was elevated in ß-cells treated with PA/glucose. mTORC1 inhibition, by treatment with rapamycin, reversed changes in autophagic flux, and cell death induced by glucose/PA. Our results indicate that nutrient toxicity-induced cell death occurs via impaired autophagy and is mediated by activation of mTORC1 in ß-cells, contributing to ß-cell failure in the presence of metabolic stress.


Assuntos
Apoptose/genética , Autofagia/genética , Diabetes Mellitus/genética , Complexos Multiproteicos/genética , Serina-Treonina Quinases TOR/genética , Adulto , Animais , Proteína 7 Relacionada à Autofagia , Linhagem Celular , Diabetes Mellitus/patologia , Ácidos Graxos/metabolismo , Feminino , Glucose/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Transdução de Sinais , Enzimas Ativadoras de Ubiquitina/metabolismo
15.
Autophagy ; 9(10): 1566-78, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24113030

RESUMO

Autophagy resembles a recycling process in which proteins, organelles, or regions of the cytoplasm are enveloped and degraded. We have found that two of the central autophagy proteins, MAP1LC3 (microtubule-associated protein 1 light chain 3, also described as LC3) and UVRAG (UV radiation resistance associated/UV radiation associated gene), complex with PGRMC1/S2R (progesterone receptor membrane component 1, also known as sigma-2 receptor). PGRMC1 is a cytochrome that is induced in cancer and is essential for tumor formation, invasion, and metastasis. Autophagy contributes to the turnover of long-lived and/or ubiquitinated proteins and the clearance of damaged organelles, and we have shown that PGRMC1 promotes both processes. Inhibition of PGRMC1 by RNAi or small molecule inhibitors causes autophagy substrates to increase and aberrant mitochondria to accumulate. We propose that this disruption of autophagy upon PGRMC1 inhibition increases AMPK activation, elevating the levels of TSC1 (tuberous sclerosis complex) and TSC2 and inactivating MTOR and RPS6KB/p70S6K, causing cleaved MAP1LC3B levels to increase. Thus, PGRMC1 binds to key components of the autophagy machinery and is required for the degradative activity of autophagy.


Assuntos
Autofagia/fisiologia , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Receptores de Progesterona/metabolismo , Receptores sigma/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Humanos , Proteólise , Receptores de Progesterona/efeitos dos fármacos , Receptores sigma/efeitos dos fármacos , Proteína Sequestossoma-1 , Esclerose Tuberosa/metabolismo
16.
J Biol Chem ; 287(18): 14494-501, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22418433

RESUMO

Tumor invasion is a critical step in the spread of cancer. S2R (sigma-2 receptor)/Pgrmc1 (progesterone receptor membrane component 1) is a cytochrome b(5)-related drug-binding orphan receptor essential for tumor formation and invasion. Secretory proteins drive these processes, so we screened for S2R(Pgrmc1)-dependent secreted proteins using antibody arrays. S2R(Pgrmc1) markedly regulated the expression of NGAL/LCN2 (neutrophil gelatinase-associated lipocalin/lipocalin 2), a secreted glycoprotein that binds to MMP-9 (matrix metalloproteinase 9) and protects it from degradation. S2R(Pgrmc1) knock-down blocked NGAL/LCN2 expression at the protein and RNA levels and decreased MMP9 activity. NGAL expression was required for MMP-9 activity and tumor formation. S2R(Pgrmc1) associates with EGFR and increases EGFR levels at the plasma membrane, and the EGFR inhibitors erlotinib and AG1478, as well as Akt and ERK inhibitors, suppressed the NGAL/LCN2 RNA and protein levels. NGAL is transcriptionally regulated by NFκB, and S2R(Pgrmc1) knock-down decreased the NFκB subunit p65/RelA acetylation, phosphorylation, and activation. In S2R(Pgrmc1) knock-down cells, p65 acetylation was reversed by inhibitors of histone deacetylase 1, and the inhibitors partially restored NGAL levels. Our results are consistent with a model in which S2R(Pgrmc1) increases NGAL/LCN2 levels by activating NFκB via EGFR.


Assuntos
Proteínas de Fase Aguda/biossíntese , Membrana Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Lipocalinas/biossíntese , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Receptores de Progesterona/metabolismo , Acetilação/efeitos dos fármacos , Proteínas de Fase Aguda/genética , Animais , Linhagem Celular Tumoral , Membrana Celular/genética , Membrana Celular/patologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Lipocalina-2 , Lipocalinas/genética , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , Modelos Biológicos , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/genética , Quinazolinas/farmacologia , Receptores de Progesterona/genética , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Transplante Heterólogo , Tirfostinas/farmacologia
17.
Int J Cancer ; 131(2): E1-9, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21918976

RESUMO

Cancer is one of the leading causes of death, and there is an urgent need for new biomarkers and therapeutic targets. The progesterone receptor membrane component 1 (Pgrmc1) protein is upregulated in multiple types of cancer, and Pgrmc1 is required for tumor cell proliferation, motility and tumor formation in vivo. Furthermore, a small molecule inhibitor of Pgrmc1 suppressed the growth of lung, breast and cervical cancer cell lines. Recently, Pgrmc1 was identified as the sigma-2 receptor, a putative type of opioid receptor, and sigma-2 receptors are induced in cancers. However, Pgrmc1 shares no homology with known opioid or hormone receptors but is related to cytochrome b(5), and Pgrmc1 binds to heme and has reducing activity. In this study, we have analyzed Pgrmc1 levels in clinical tumor samples from squamous cell lung cancers (SCLC) and lung adenocarcinomas compared to corresponding nonmalignant tissue. Pgrmc1 levels increased significantly (p ≤ 0.05) in 12/15 SCLC samples and was elevated in poorly differentiated tumors. Pgrmc1 was highly expressed in SCLC cell lines, and SCLC cell survival was inhibited by siRNA knockdown of Pgrmc1 or the Pgrmc1 inhibitor AG-205. In adenocarcinomas, 6/15 tumors significantly had elevated Pgrmc1 levels, which correlated with patient survival. Pgrmc1 localizes to secretory vesicles in cancer cells, and Pgrmc1 was secreted by lung cancer cells. Furthermore, Pgrmc1 was significantly elevated in the plasma of lung cancer patients compared to noncancer patients. Together, the results demonstrate that Pgrmc1 is a potential tumor and serum biomarker, as well as a therapeutic target, for lung cancer.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias de Células Escamosas/metabolismo , Receptores de Progesterona/metabolismo , Adenocarcinoma/sangue , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Neoplasias Pulmonares/sangue , Masculino , Proteínas de Membrana/sangue , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Neoplasias de Células Escamosas/sangue , Interferência de RNA , RNA Interferente Pequeno , Receptores de Progesterona/sangue , Receptores de Progesterona/genética , Receptores sigma/sangue , Receptores sigma/genética , Receptores sigma/metabolismo
18.
Indian J Pharmacol ; 43(2): 172-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21572652

RESUMO

OBJECTIVES: To compare the effectiveness and tolerability of misoprostol as a cervical ripening agent in first trimester abortion through three different routes of administration before surgical evacuation (SE). MATERIALS AND METHODS: It was a hospital based prospective randomized open labeled parallel study. A total of 150 randomly selected married women were divided in three groups for sublingual (S/L), vaginal and oral 400 µg of misoprostol single dose administration. The drug was administered 3-4 h before SE in the S/L and vaginal groups and 12 h before the procedure in the oral group. Efficacy was assessed on the basis of time taken for ripening, dilatation achieved, duration of the procedure, intra-operative blood loss, and pain score. The tolerability was noted on the basis of side effects. RESULTS: The mean time taken for cervical ripening was less in sublingual administration (3.7±1.2 hr) as compared to the vaginal and oral routes. The S/L group had significant cervical dilatation (P<0.001) and the duration of SE was less as compared to the vaginal and oral routes. However, the mean intraoperative blood loss was more in sublingual as compared to the vaginal and oral groups. The intra-operative pain score of the S/L group was significantly lower (1.9±1.1, P<0.05) as compared to the vaginal (2.6±1.7) or oral route (3.3±1.7). Loose motions and nausea/vomiting were more with the S/L and oral routes while blood loss was more in the vaginal route. CONCLUSION: Administration of misoprostol by the sublingual route is better than the oral and vaginal routes for cervical ripening.

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