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1.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361745

RESUMO

The edible parts of the plants Camellia sinensis, Vitis vinifera and Withania somnifera were extensively used in ancient practices such as Ayurveda, owing to their potent biomedical significance. They are very rich in secondary metabolites such as polyphenols, which are very good antioxidants and exhibit anti-carcinogenic properties. This study aims to evaluate the anti-cancerous properties of these plant crude extracts on human liver cancer HepG2 cells. The leaves of Camellia sinensis, Withania somnifera and the seeds of Vitis vinifera were collected and methanolic extracts were prepared. Then, these extracts were subjected to DPPH, α- amylase assays to determine the antioxidant properties. A MTT assay was performed to investigate the viability of the extracts of HepG2 cells, and the mode of cell death was detected by Ao/EtBr staining and flow cytometry with PI Annexin- V FITC dual staining. Then, the protein expression of BAX and BCl2 was studied using fluorescent dye to determine the regulation of the BAX and BCl2 genes. We observed that all the three extracts showed the presence of bioactive compounds such as polyphenols or phytochemicals. The W. somnifera bioactive compounds were found to have the highest anti-proliferative activity on human liver cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Camellia sinensis/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vitis/química , Withania/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Morte Celular/efeitos dos fármacos , Flavonoides/química , Flavonoides/isolamento & purificação , Células Hep G2 , Humanos , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sementes/química , Transdução de Sinais , Taninos/química , Taninos/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação , alfa-Amilases/genética , alfa-Amilases/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
2.
Curr Med Chem ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38409699

RESUMO

INTRODUCTION: Metformin, a biguanide on the WHO's list of essential medicines has a long history of 50 years or more in treating hyperglycemia, and its therapeutic saga continues beyond diabetes treatment. Glucoregulatory actions are central to the physiological effects of metformin; surprisingly, the precise mechanism with which metformin regulates glucose metabolism is not thoroughly understood yet. METHOD: The main aim of this review is to explore the recent implications of metformin in hepatic gluconeogenesis, AMPKs, and SHIP2 and subsequently to elucidate the metformin action across intestine and gut microbiota. We have searched PubMed, google scholar, Medline, eMedicine, National Library of Medicine (NLM), clinicaltrials.gov (registry), and ReleMed for the implications of metformin with its updated role in AMPKs, SHIP2, and hepatic gluoconeogenesis, and gut microbiota. In this review, we have described the efficacy of metformin as a drug repurposing strategy in modulating the role of AMPKs and lysosomal-AMPKs, and controversies associated with metformin. RESULT: Research suggests that biguanide exhibits hormetic effects depending on the concentrations used (micromolar to millimolar). The primary mechanism attributed to metformin action is the inhibition of mitochondrial complex I, and subsequent reduction of cellular energy state, as observed with increased AMP or ADP ratio, thereby metformin can also activate the cellular energy sensor AMPK to inhibit hepatic gluconeogenesis. However, new mechanistic models have been proposed lately to explain the pleiotropic actions of metformin; at low doses, metformin can activate lysosomal-AMPK via the AXIN-LKB1 pathway. Conversely, in an AMPK-independent mechanism, metformin-induced elevation of AMP suppresses adenylate cyclase and glucagon-activated cAMP production to inhibit hepatic glucose output by glucagon. Metformin inhibits mitochondrial glycerophosphate dehydrogenase; mGPDH, and increases the cytosolic NADH/NAD+, affecting the availability of lactate and glycerol for gluconeogenesis. Metformin can inhibit Src homology 2 domain-containing inositol 5-phosphatase 2; SHIP2 to increase the insulin sensitivity and glucose uptake by peripheral tissues. CONCLUSION: In addition, new exciting mechanisms suggest the role of metformin in promoting beneficial gut microbiome and gut health; metformin regulates duodenal AMPK activation, incretin hormone secretion, and bile acid homeostasis to improve intestinal glucose absorption and utilization.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36415754

RESUMO

Inherited neurotransmitter diseases are a subset of rare neurometabolic disorders characterized by hereditary deficiencies in neurotransmitter metabolism or transport. Non-ketotic hyperglycinaemia (NKH), called glycine encephalopathy, is an autosomal recessive glycine metabolism disorder characterized by an abnormal accumulation of glycine in all bodily tissues, including the CNS. The SLC6A9 gene, which codes for the GLYT1 protein, a biochemical abnormality in the GCS, and dihydrolipoamide dehydrogenase enzymes, which function as a GCS component, are responsible for the neonatal form's symptoms, which include progressive encephalopathy, hypotonia, seizures, and occasionally mortality in the first few days of life. By changing the MAPK signalling pathways, glycine deprivation in the brain damages neurons by increasing NMDA receptor activation, increasing intracellular Ca levels, and leading to DNA breakage and cell death in the neuron region. In addition to the previously mentioned clinical diagnosis, NKH or GE would be determined by MLPA and 13C glycine breath tests. Pediatricians, surgeons, neurologists, and geneticists treat NKH and GE at the newborn period; there is no cure for either condition.

4.
Curr Protein Pept Sci ; 23(10): 672-683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111757

RESUMO

Nuclear factor erythroid 2 (NFE 2) - related factor 2 (NFE2L2 or NRF2) is one of the transcription factors predominantly related to the expression of antioxidant genes. NRF2 plays a pivotal role in controlling redox potential in several tumor characteristics, including cancer cell metabolism, stem-cell-like characteristics, tumor aggressiveness, invasion, and metastasis. Further, it was recently discovered that the noncanonical pathway of NRF2 activation was involved in carcinogenesis. Cancerrelated changes (e.g., metabolic flexibility) that support cancer progression were found to be redox and NRF2 dependent. The pro or antineoplastic effects of NRF2 are essentially based on the specific molecular characteristics of the type of cancer. Therefore, systematic investigation of NRF2 signaling is necessary to clarify its role in cancer etiology. Understanding the role of NRF2 in triggering gene expressions in different types of cancer is quite challenging, which might be useful to target those genes for better clinical outcomes. To decipher the role of NRF2 in tumor formation and progression, largescale genomic and transcriptomic studies are required to correlate the clinical outcomes with the activity of the NRF2 expression system. This review attempts to give insights into the understanding of the role of NRF2 in cancer.


Assuntos
Fator 2 Relacionado a NF-E2 , Neoplasias , Humanos , Carcinogênese/metabolismo , Neoplasias/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Transdução de Sinais
5.
Am J Physiol Gastrointest Liver Physiol ; 301(5): G905-11, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21868633

RESUMO

Intermediate-conductance K(+) (Kcnn4) channels in the apical and basolateral membranes of epithelial cells play important roles in agonist-induced fluid secretion in intestine and colon. Basolateral Kcnn4 channels have been well characterized in situ using patch-clamp methods, but the investigation of Kcnn4 channels in apical membranes in situ has been hampered by a layer of mucus that prevents seal formation. In the present study, we used patch-clamp methods to characterize Kcnn4 channels in the apical membrane of IEC-18 cells, a cell line derived from rat small intestine. A monolayer of IEC-18 cells grown on a permeable support is devoid of mucus, and tight junctions enable selective access to the apical membrane. In inside-out patches, Ca(2+)-dependent K(+) channels observed with iberiotoxin (a Kcnma1/large-conductance, Ca(2+)-activated K(+) channel blocker) and apamin (a Kcnn1-3/small-conductance, Ca(2+)-activated K(+) channel blocker) present in the pipette solution exhibited a single-channel conductance of 31 pS with inward rectification. The currents were reversibly blocked by TRAM-34 (a Kcnn4 blocker) with an IC(50) of 8.7 ± 2.0 µM. The channels were not observed when charybdotoxin, a peptide inhibitor of Kcnn4 channels, was added to the pipette solution. TRAM-34 was less potent in inhibiting Kcnn4 channels in patches from apical membranes than in patches from basolateral membranes, which was consistent with a preferential expression of Kcnn4c and Kcnn4b isoforms in apical and basolateral membranes, respectively. The expression of both isoforms in IEC-18 cells was confirmed by RT-PCR and Western blot analyses. This is the first characterization of Kcnn4 channels in the apical membrane of intestinal epithelial cells.


Assuntos
Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Mucosa Intestinal/metabolismo , Animais , Linhagem Celular , Células Epiteliais/citologia , Mucosa Intestinal/citologia , Intestinos/citologia , Potenciais da Membrana/fisiologia , Ratos
6.
PLoS One ; 15(3): e0229463, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32214355

RESUMO

Food and feeds contaminated with mycotoxins have been a threat to the rearing industry by causing some of the most fatal toxic reactions not only in the farm animals but also in humans who consume them. Toxicity to juvenile goats was induced by feed contamination with T-2 toxin (at 10 and 20 ppm dosage; group I and II, respectively). The toxicity impact was assessed on days 15 and 30 post treatment with respect to growth performance, oxidative stress, apoptotic studies and detailed pathomorphology. The study revealed that apart from the obvious clinical toxicosis (weakness, lethargy, and retardation in growth), the toxin fed groups also exhibited significant haematological (reduced hemoglobin, total leukocyte and thrombocyte counts) and biochemical changes (increased levels of oxidative stress markers with concomitant decrease in levels of serum and tissue catalase and superoxide dismutase). The pathomorphological and histological alterations suggested that the liver and intestine were the most affected organs. Ultra-structurally, varying degrees of degeneration, cytoplasmic vacuolations and pleomorphic mitochondria were observed in the hepatocytes and the enterocytes of the intestine. Kidney also revealed extensive degeneration of the cytoplasmic organelles with similar condensation of the heterochromatin whereas the neuronal degeneration was characterized by circular, whirling structures. In addition, the central vein and portal triad of the hepatocytes, cryptic epithelial cells of the intestine, MLNs in the lymphoid follicles, PCT and DCT of the nephronal tissues and the white pulp of the spleen exhibited extensive apoptosis. In this study, it was also observed that the expression of HSPs, pro-apoptotic proteins and pro-inflammatory cytokines were significantly upregulated in response to the toxin treatment. These results suggest that the pathogenesis of T-2 toxicosis in goats employs oxidative, apoptotic and inflammatory mechanisms.


Assuntos
Apoptose , Regulação da Expressão Gênica/efeitos dos fármacos , Cabras/fisiologia , Mediadores da Inflamação/metabolismo , Fígado/patologia , Estresse Oxidativo/efeitos dos fármacos , Toxina T-2/toxicidade , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Citocinas/metabolismo , Proteínas de Choque Térmico/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Linfonodos/patologia , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia
7.
Stem Cell Investig ; 5: 5, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29682512

RESUMO

Cancer stem cells (CSCs) have been defined as cells within tumor that possess the capacity to self-renew and to cause the heterogeneous lineages of cancer cells that comprise the tumor. CSCs have been increasingly identified in blood cancer, prostate, ovarian, lung, melanoma, pancreatic, colon, brain and many more malignancies. CSCs have slow growth rate and are resistant to chemotherapy and radiotherapy that lead to the failure of traditional current therapy. Eradicating the CSCs and recurrence, is promising aspect for the cure of cancer. The CSCs like any other stem cells activate the signal transduction pathways that involve the development and tissue homeostasis, which include Notch signaling pathway. The new treatment targets these pathway that control stem-cell replication, survival and differentiation that are under development. Notch inhibitors either single or in combination with chemotherapy drugs have been developed to treat cancer and its recurrence. This approach of targeting signaling pathway of CSCs represents a promising future direction for the therapeutic strategy to cure cancer.

8.
PLoS One ; 8(11): e80304, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260365

RESUMO

Hepatitis C virus (HCV)-induced alterations in lipid metabolism and cellular protein expression contribute to viral pathogenesis. The mechanism of pleiotropic actions of cholesterol-lowering drugs, statins, against HCV and multiple cancers are not well understood. We investigated effects of fluvastatin (FLV) on microtubule-associated and cancer stem cell marker (CSC), doublecortin-like kinase 1 (DCLK1) during HCV-induced hepatocarcinogenesis. HCV replication models, cancer cell lines and normal human hepatocytes were used to investigate the antiviral and antitumor effects of statins. FLV treatment resulted in induction of microtubule bundling, cell-cycle arrest and alterations in cellular DCLK1 distribution in HCV-expressing hepatoma cells. These events adversely affected the survival of liver-derived tumor cells without affecting normal human hepatocytes. FLV downregulated HCV replication in cell culture where the ATP pool and cell viability were not compromised. Pravastatin did not exhibit these effects on HCV replication, microtubules and cancer cells. The levels of miR-122 that regulates liver homeostasis and provides HCV genomic stability remained at steady state whereas DCLK1 mRNA levels were considerably reduced during FLV treatment. We further demonstrated that HCV replication was increased with DCLK1 overexpression. In conclusion, unique effects of FLV on microtubules and their binding partner DCLK1 are likely to contribute to its anti-HCV and antitumor activities in addition to its known inhibitory effects on 3-hydroxy-3-methylglutary-CoA reductase (HMGCR).


Assuntos
Ácidos Graxos Monoinsaturados/farmacologia , Hepacivirus/efeitos dos fármacos , Indóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Replicação Viral/efeitos dos fármacos , Antineoplásicos/farmacologia , Antivirais/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Quinases Semelhantes a Duplacortina , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Fluvastatina , Hepacivirus/genética , Hepacivirus/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microtúbulos/genética , Proteínas Serina-Treonina Quinases/genética , Replicação Viral/genética
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