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1.
Antiviral Res ; 225: 105874, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38555023

RESUMO

The main protease (MPro) of SARS-CoV-2, the causative agent of COVID-19, is a pivotal nonstructural protein critical for viral replication and pathogenesis. Its protease function relies on three active site pockets for substrate recognition and a catalytic cysteine for enzymatic activity. To develop potential SARS-CoV-2 antivirals, we successfully synthesized a diverse range of azapeptide inhibitors with various covalent warheads to target MPro's catalytic cysteine. Our characterization identified potent MPro inhibitors, including MPI89 that features an aza-2,2-dichloroacetyl warhead with a remarkable EC50 value of 10 nM against SARS-CoV-2 infection in ACE2+ A549 cells and a selective index of 875. MPI89 is also remarkably selective and shows no potency against SARS-CoV-2 papain-like protease and several human proteases. Crystallography analyses demonstrated that these inhibitors covalently engaged the catalytic cysteine and used the aza-amide carbonyl oxygen to bind to the oxyanion hole. MPI89 stands as one of the most potent MPro inhibitors, suggesting the potential for further exploration of azapeptides and the aza-2,2-dichloroacetyl warhead for developing effective therapeutics against COVID-19.


Assuntos
COVID-19 , Proteases 3C de Coronavírus , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Cisteína , Cisteína Endopeptidases/metabolismo , Proteínas não Estruturais Virais , Inibidores de Proteases/farmacologia , Antivirais/farmacologia
2.
Dysphagia ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381156

RESUMO

Dysphagia is a significant health concern especially amongst the old age population. It is an ailment brought on by the weakening of the swallowing muscles. To reduce the risk of choking in dysphagia patients, the food is usually diluted to suit their swallowing ability. But dilution results in reducing the nutritional density of the foods thus causing undernutrition and malnutrition in patients. In this study, functional liquid diets were formulated under International Dysphagia Diet Standardization Initiative (IDDSI) levels 0-2. The developed diets were analysed for their proximate composition, colour, antioxidant and sensory properties. Antioxidant activities were determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and total phenolic content (TPC) methods. The highest ABTS+ value was observed in pumpkin puree (level-2) i.e. 98.59%. Black carrot juice (level-1) showed the highest DPPH free radical scavenging activity and FRAP value viz. 88.43% and 689.33 µM TE/g, respectively. Electromyography (EMG) is an upcoming technique of food texture evaluation which provides real-time information about food oral processing. In this study, an EMG was conducted to measure the myoelectrical activity of human suprahyoid and masseter muscles by placing electrodes on the skin's surface during the oral processing of liquid. The EMG parameters correlated significantly with viscosity, ease of swallowing and IDDSI levels of the formulated diets. Hence EMG can be used as a tool for design and development of textured-modified diets for dysphagia patients. The sensory scores of formulated diets in this study were high indicating that these liquid diets may be incorporated into the diet plans of dysphagia patients.

3.
Cell Mol Life Sci ; 81(1): 21, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38196006

RESUMO

BCL6 translocation is one of the most common chromosomal translocations in cancer and results in its enhanced expression in germinal center B cells. It involves the fusion of BCL6 with any of its twenty-six Ig and non-Ig translocation partners associated with diffuse large B cell lymphoma (DLBCL). Despite being discovered long back, the mechanism of BCL6 fragility is largely unknown. Analysis of the translocation breakpoints in 5' UTR of BCL6 reveals the clustering of most of the breakpoints around a region termed Cluster II. In silico analysis of the breakpoint cluster sequence identified sequence motifs that could potentially fold into non-B DNA. Results revealed that the Cluster II sequence folded into overlapping hairpin structures and identified sequences that undergo base pairing at the stem region. Further, the formation of cruciform DNA blocked DNA replication. The sodium bisulfite modification assay revealed the single-strandedness of the region corresponding to hairpin DNA in both strands of the genome. Further, we report the formation of intramolecular parallel G4 and triplex DNA, at Cluster II. Taken together, our studies reveal that multiple non-canonical DNA structures exist at the BCL6 cluster II breakpoint region and contribute to the fragility leading to BCL6 translocation in DLBCL patients.


Assuntos
Linfoma Difuso de Grandes Células B , Translocação Genética , Humanos , Translocação Genética/genética , Rearranjo Gênico , Linfoma Difuso de Grandes Células B/genética , Linfócitos B , Regiões 5' não Traduzidas , DNA , Proteínas Proto-Oncogênicas c-bcl-6/genética
4.
ACS Omega ; 8(43): 40729-40740, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929147

RESUMO

A chemical inhibitor of antiapoptotic protein, BCL2, known as Disarib, suffers poor solubility in aqueous environments; thereby limiting its potential as a chemotherapeutic agent. To overcome this limitation and enhance the therapeutic efficacy of Disarib, we have employed the encapsulation of this small molecule inhibitor within P123 copolymer matrix. Micelles were synthesized using a thin-film hydration technique, and a comprehensive analysis was undertaken to evaluate the resulting micelle properties, including morphology, particle size, intermolecular interactions, encapsulation efficiency, and in vitro release characteristics. This assessment utilized various physicochemical techniques including UV spectroscopy, FTIR spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). Disarib-loaded P123 micelle formulation denoted as P123D exhibited a well-defined particle size of approximately 29.2 nm spherical core-shell morphology. Our investigations revealed a notable encapsulation efficiency of 75%, and we observed a biphasic release pattern for the encapsulated Disarib. Furthermore, our cytotoxicity assessment of P123D micelles against mouse breast adenocarcinoma, mouse lymphoma, and human leukemic cell lines showed 40-45% increase in cytotoxicity compared with the administration of Disarib alone in the breast adenocarcinoma cell line. Enhancement in the cytotoxicity of P123D was found to be higher or limited; however, it is important to observe that the encapsulation method significantly enhanced the aqueous solubility of Disarib as it has the best solubility in dimethyl sulfoxide (DMSO) in the unencapsulated state.

5.
J Biol Chem ; 299(12): 105431, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37926284

RESUMO

t(8;14) translocation is the hallmark of Burkitt's lymphoma and results in c-MYC deregulation. During the translocation, c-MYC gene on chromosome 8 gets juxtaposed to the Ig switch regions on chromosome 14. Although the promoter of c-MYC has been investigated for its mechanism of fragility, little is known about other c-MYC breakpoint regions. We have analyzed the translocation break points at the exon 1/intron 1 of c-MYC locus from patients with Burkitt's lymphoma. Results showed that the breakpoint region, when present on a plasmid, could fold into an R-loop confirmation in a transcription-dependent manner. Sodium bisulfite modification assay revealed significant single-strandedness on chromosomal DNA of Burkitt's lymphoma cell line, Raji, and normal lymphocytes, revealing distinct R-loops covering up to 100 bp region. Besides, ChIP-DRIP analysis reveals that the R-loop antibody can bind to the breakpoint region. Further, we show the formation of stable parallel intramolecular G-quadruplex on non-template strand of the genome. Finally, incubation of purified AID in vitro or overexpression of AID within the cells led to enhanced mutation frequency at the c-MYC breakpoint region. Interestingly, anti-γH2AX can bind to DSBs generated at the c-MYC breakpoint region within the cells. The formation of R-loop and G-quadruplex was found to be mutually exclusive. Therefore, our results suggest that AID can bind to the single-stranded region of the R-loop and G4 DNA, leading to the deamination of cytosines to uracil and induction of DNA breaks in one of the DNA strands, leading to double-strand break, which could culminate in t(8;14) chromosomal translocation.


Assuntos
Linfoma de Burkitt , Quadruplex G , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , DNA , Genes myc , Estruturas R-Loop , Translocação Genética
6.
Molecules ; 28(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446888

RESUMO

Despite several treatment options for blood cancer, mortality remains high due to relapse and the disease's aggressive nature. Elevated levels of HSP90, a molecular chaperone essential for protein folding, are associated with poor prognosis in leukemia and lymphoma. HSP90 as a target for chemotherapy has been met with limited success due to toxicity and induction of heat shock. This study tested the activity of an HSP90 inhibitor, SP11, against leukemic cells, mouse lymphoma allograft, and xenograft models. SP11 induced cytotoxicity in vitro in leukemic cell lines and induced cell death via apoptosis, with minimal effect on normal cells. SP11 induced cell death by altering the status of HSP90 client proteins both in vitro and in vivo. SP11 reduced the tumor burden in allograft and xenograft mouse models without apparent toxicity. The half-life of SP11 in the plasma was approximately 2 h. SP11 binding was observed at both the N-terminal and C-terminal domains of HSP90. C-terminal binding was more potent than N-terminal binding of HSP90 in silico and in vitro using isothermal calorimetry. SP11 bioavailability and minimal toxicity in vivo make it a potential candidate to be developed as a novel anticancer agent.


Assuntos
Antineoplásicos , Cumarínicos , Humanos , Animais , Camundongos , Cumarínicos/farmacologia , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP90/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Dobramento de Proteína , Apoptose
7.
Med Chem ; 19(9): 848-858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37055895

RESUMO

Quinoline and its analogues are found in various natural products, many of which are active pharmacophores with significant bioactivities. This article discussed the plethora of quinoline derivatives and their analogues that have anti-cancer properties. The review will be helpful for the scientific community since several possible anticancer drugs based on quinolines are discussed here. In addition to this, the synthetic aspect of many such quinoline derivatives showing anti-cancer activities is also revealed in this article. These quinoline-based anti-oncogenic molecules can be synthesized using several acids, bases, and azides or with the help of reagents like Jone's reagent and Lawesson's reagent.


Assuntos
Antineoplásicos , Neoplasias , Quinolinas , Humanos , Neoplasias/tratamento farmacológico , Indicadores e Reagentes/uso terapêutico
8.
Interdiscip Perspect Infect Dis ; 2023: 1618082, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655217

RESUMO

Quinoline-based molecules are major constituents in natural products, active pharmacophores, and have excellent biological activities. Using 2H-thiopyrano[2,3-b]quinoline derivatives and CB1a protein (PDB ID: 2IGR), the molecular docking study has been revealed in this article. The study of in silico molecular docking analysis of such derivatives to determine the binding affinity, residual interaction, and hydrogen bonding of several 2H-thiopyrano[2,3-b]quinolines against CB1a is reported here. The current work demonstrated that 2H-thiopyrano[2,3-b]quinoline derivatives could be effective antitumor agents to produce potent anticancer medicines in the near future.

9.
FEBS J ; 290(3): 796-820, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36048168

RESUMO

Mercaptopyrimidine derivatives are heterocyclic compounds with potent biological activities including antiproliferative, antibacterial, and anti-inflammatory properties. The present study describes the synthesis and characterization of several mercaptopyrimidine derivatives through condensation of 5,6-diamino-2-mercaptopyrimidin-4-ol with various heterocyclic and aromatic aldehydes. Previous studies have shown that SCR7, synthesized from 5,6-diamino-2-mercaptopyrimidin-4-ol, induced cytotoxicity by targeting cancer cells by primarily inhibiting DNA Ligase IV involved in nonhomologous end joining, one of the major DNA double-strand break repair pathways. Inhibition of DNA repair pathways is considered as an important strategy for cancer therapy. Due to limitations of SCR7 in terms of IC50 in cancer cells, here we have designed, synthesized, and characterized potent derivatives of SCR7 using 5,6-diamino-2-mercaptopyrimidin-4-ol as the starting material. Several synthesized imine compounds exhibited significant improvement in inhibition of end joining and cytotoxicity up to 27-fold lower concentrations than SCR7. Among these, two compounds, SCR116 and SCR132, showed increased cancer cell death in a Ligase IV-dependent manner. Treatment with the compounds also led to reduction in V(D)J recombination efficiency, cell cycle arrest at G2/M phase, accumulation of double-strand breaks inside cells, and improved anti-cancer potential when combined with γ-radiation and radiomimetic drugs. Thus, we describe novel inhibitors of NHEJ with higher efficacy and potential, which can be developed as cancer therapeutics.


Assuntos
Reparo do DNA por Junção de Extremidades , Neoplasias , Humanos , Neoplasias/genética , Reparo do DNA , Quebras de DNA de Cadeia Dupla , DNA/metabolismo
10.
Curr Org Synth ; 20(6): 606-629, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36200204

RESUMO

Quinoline derivatives are an important class of heterocyclic compounds and possess various applications in synthetic organic chemistry, medicinal chemistry, material chemistry and natural product chemistry. This review article describes the different quinoline derivatives having antimalarial, analgesic, anti-inflammatory, antineoplastic, antibacterial, antifungal, antiviral, anthelmintic, antiprotozoal, cardiovascular, CNS and other useful bioactivities. We have delineated the general synthetic routes for the synthesis of many bioactive quinoline based heterocycles. In addition to this, we have also discussed the crucial synthetic routes as well as their mechanistic paths for the formation of bioactive quinoline derivatives. The study shows that substitution at the 4 and 8- position of quinoline is more crucial for bioactivity as compared to other positions.


Assuntos
Anti-Infecciosos Locais , Anti-Infecciosos , Antiprotozoários , Hidroxiquinolinas , Quinolinas , Anti-Infecciosos/farmacologia , Analgésicos , Anti-Inflamatórios
11.
Elife ; 112022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36394256

RESUMO

Having its genome makes the mitochondrion a unique and semiautonomous organelle within cells. Mammalian mitochondrial DNA (mtDNA) is a double-stranded closed circular molecule of about 16 kb coding for 37 genes. Mutations, including deletions in the mitochondrial genome, can culminate in different human diseases. Mapping the deletion junctions suggests that the breakpoints are generally seen at hotspots. '9 bp deletion' (8271-8281), seen in the intergenic region of cytochrome c oxidase II/tRNALys, is the most common mitochondrial deletion. While it is associated with several diseases like myopathy, dystonia, and hepatocellular carcinoma, it has also been used as an evolutionary marker. However, the mechanism responsible for its fragility is unclear. In the current study, we show that Endonuclease G, a mitochondrial nuclease responsible for nonspecific cleavage of nuclear DNA during apoptosis, can induce breaks at sequences associated with '9 bp deletion' when it is present on a plasmid or in the mitochondrial genome. Through a series of in vitro and intracellular studies, we show that Endonuclease G binds to G-quadruplex structures formed at the hotspot and induces DNA breaks. Therefore, we uncover a new role for Endonuclease G in generating mtDNA deletions, which depends on the formation of G4 DNA within the mitochondrial genome. In summary, we identify a novel property of Endonuclease G, besides its role in apoptosis and the recently described 'elimination of paternal mitochondria during fertilisation.


Assuntos
Genoma Mitocondrial , Humanos , Animais , Endodesoxirribonucleases , Mitocôndrias/genética , Instabilidade Genômica , DNA Mitocondrial/genética , Mamíferos
12.
ACS Phys Chem Au ; 2(4): 353-363, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36855421

RESUMO

The conformational transitions of the adenosine deaminase A-riboswitch aptamer both with and without ligand binding are investigated within the tenets of the generalized Langevin equation in a complex viscoelastic cellular environment. Steered molecular dynamics (SMD) simulations are performed to evaluate and compare the results of the first passage times (FPTs) with those obtained from the theory for the unfold and fold transitions of the aptamer. The results of the distribution of Kramers's FPT reveal that the unfold-fold transitions are faster and hence more probable as compared to the fold-unfold transitions of the riboswitch aptamer for both ligand-bound and -unbound states. The transition path time is lower than Kramers's FPT for the riboswitch aptamer as the transition path times for the unfold-fold transition of both without and with ligand binding are insensitive to the details of the exact mechanism of the transition events. However, Kramers's FPTs show varied distributions which correspond to different transition pathways, unlike the transition path times. The mean FPT increases with an increase in the complexity of the cellular environment. The results of Kramers's FPT, transition path time distribution, and mean FPT obtained from our calculations qualitatively match with those obtained from the SMD simulations. Analytically derived values of the mean transition path time show good quantitative agreement with those estimated from the single-molecule force spectroscopy experiments for higher barrier heights.

13.
J Chem Phys ; 154(18): 185101, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241023

RESUMO

The effect of ligand binding on the conformational transitions of the add A-riboswitch in cellular environments is investigated theoretically within the framework of the generalized Langevin equation combined with steered molecular dynamics simulations. Results for the transition path time distribution provide an estimate of the transit times, which are difficult to determine experimentally. The time for the conformational transitions of the riboswitch aptamer is longer for the ligand bound state as compared to that of the unbound one. The transition path time of the riboswitch follows a counterintuitive trend as it decreases with an increase in the barrier height. The mean transition path time of either transitions of the riboswitch in the ligand bound/unbound state increases with an increase in the complexity of the surrounding environment due to the caging effect. The results of the probability density function, transition path time distribution, and mean transition path time obtained from the theory qualitatively agree with those obtained from the simulations and with earlier experimental and theoretical studies.


Assuntos
Adenosina Desaminase/química , Teoria da Densidade Funcional , Simulação de Dinâmica Molecular , Adenosina Desaminase/metabolismo , Ligantes
14.
Int J Radiat Biol ; 97(9): 1166-1180, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259614

RESUMO

PURPOSE: DNA, the hereditary material of a human cell generally exists as Watson-Crick base paired double-stranded B-DNA. Studies suggest that DNA can also exist in non-B forms, such as four stranded G-quadruplexes (G4 DNA). Recently, our studies revealed that the regions of DNA that can fold into G-quadruplex structures are less sensitive to ionizing radiation (IR) compared to B-DNA. Importantly, we reported that the planar G-quartet of a G4 structure is shielded from radiation induced DNA breaks, while the single- and double-stranded DNA regions remained susceptible. Thus, in the present study, we investigate whether telomeric repeat DNA present at the end of telomere, known to fold into G4 DNA can protect from radiation induced damages including strand breaks, oxidation of purines and bulky adduct formation on DNA. MATERIALS AND METHODS: For plasmid irradiation assay, plasmids containing human telomeric repeat DNA sequence TTAGGG (0.8 kb or 1.8 kb) were irradiated with increasing doses of IR along with appropriate control plasmids and products were resolved on 1% agarose gel. Radioprotection was evaluated based on extent of conversion of supercoiled to nicked or linear forms of the DNA following irradiation. Formation of G-quadruplex structure on supercoiled DNA was evaluated based on circular dichroism (CD) spectroscopy studies. Cleavage of radiation induced oxidative damage and extent of formation of nicks was further evaluated using base and nucleotide excision repair proteins. RESULTS: Results from CD studies showed that the plasmid DNA harboring human telomeric repeats (TTAGGG) can fold into G-quadruplex DNA structures. Further, results showed that human telomeric repeat sequence when present on a plasmid can protect the plasmid DNA against IR induced DNA strand breaks, unlike control plasmids bearing random DNA sequence. CONCLUSIONS: Human telomeric repeat sequence when present on plasmids can fold into G-quadruplex DNA structures, and can protect the DNA against IR induced DNA strand breaks and oxidative damage. These results in conjunction with our previous studies suggest that telomeric repeat sequence imparts less sensitivity to IR and thus telomeres of chromosomes are protected from radiation.


Assuntos
Adutos de DNA/genética , Adutos de DNA/efeitos da radiação , Quadruplex G/efeitos da radiação , Raios gama/efeitos adversos , Estresse Oxidativo/genética , Estresse Oxidativo/efeitos da radiação , Telômero/genética , Sequência de Bases , Humanos , Telômero/efeitos da radiação
15.
Mol Carcinog ; 60(9): 627-643, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34192388

RESUMO

Nonhomologous end joining (NHEJ), one of the major DNA double-strand break repair pathways, plays a significant role in cancer cell proliferation and resistance to radio and chemotherapeutic agents. Previously, we had described a small molecule inhibitor, SCR7, which inhibited NHEJ in a DNA Ligase IV dependent manner. Here, we report that SCR7 potentiates the effect of γ-radiation (IR) that induces DNA breaks as intermediates to eradicate cancer cells. Dose fractionation studies revealed that coadministration of SCR7 and IR (0.5 Gy) in mice Dalton's lymphoma (DLA) model led to a significant reduction in mice tumor cell proliferation, which was equivalent to that observed for 2 Gy dose when both solid and liquid tumor models were used. Besides, co-treatment with SCR7 and 1 Gy of IR further improved the efficacy. Notably, there was no significant change in blood parameters, kidney and liver functions upon combinatorial treatment of SCR7 and IR. Further, the co-treatment of SCR7 and IR resulted in a significant increase in unrepaired DSBs within cancer cells compared to either of the agent alone. Anatomy, histology, and other studies in tumor models confirmed the cumulative effects of both agents in activating apoptotic pathways to induce cytotoxicity by modulating DNA damage response and repair pathways. Thus, we report that SCR7 has the potential to reduce the side effects of radiotherapy by lowering its effective dose ex vivo and in mice tumor models, with implications in cancer therapy.


Assuntos
Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Reparo do DNA por Junção de Extremidades/efeitos da radiação , Pirimidinas/farmacologia , Radiação Ionizante , Radiossensibilizantes/farmacologia , Bases de Schiff/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA Ligase Dependente de ATP/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Sci Rep ; 11(1): 9982, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976278

RESUMO

Apoptosis or programmed cell death is a highly regulated process, which eliminates unwanted and damaged cells. Inhibition of apoptosis is a hallmark of cancer cells. BCL2 family proteins are known to play a vital role in the regulation of apoptosis. Overexpression of BCL2, an antiapoptotic protein, provides the advantage of prolonged survival to cancer cells. Over the years, several BCL2 inhibitors have been investigated extensively for their anticancer potential. However, most of them were abolished before clinical use due to their side effects. Previously, we had identified and characterized a novel BCL2 inhibitor, Disarib, with the potential to eliminate tumor cells in a BCL2 specific manner leading to reduction in tumor burden in multiple mouse models. Notably, a head-to-head comparison of Disarib to ABT199, the only FDA approved BCL2 inhibitor revealed that Disarib is as potent as ABT199. Recent studies using mice revealed that Disarib did not invoke significant side effects in mice. In the present study, we have investigated the acute toxicity of Disarib in Wistar rats. The bioavailability studies following exposure of Disarib in Wistar rats revealed its maximum availability in serum at 24 h following oral administration. Acute toxicity analysis revealed that even a dose as high as 2000 mg/kg of Disarib did not cause significant toxicity in rats. There was no significant variation in blood parameters or kidney and liver functions following administration of Disarib. Histological analysis of different tissues from Disarib treated groups revealed standard architecture with no observable cellular damage. Importantly, exposure to Diasrib did not result in genotoxicity as determined by micronucleus assay. Further, solubility assays revealed that besides DMSO, Disarib is also soluble in alcohol. While the high acidic condition can increase the solubility of Disarib, even a lower percentage of alcohol with acidic conditions can improve its solubility. Thus, the toxicological profile in the current study revealed no significant side effects when Disarib was administered orally to rats.


Assuntos
Indóis/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Tiadiazóis/toxicidade , Animais , Disponibilidade Biológica , Indóis/farmacocinética , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Ratos Wistar , Tiadiazóis/farmacocinética , Testes de Toxicidade Aguda
17.
Sci Rep ; 10(1): 15188, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938954

RESUMO

Small molecule inhibitors targeting BCL2 are explored as anticancer therapeutics. Previously, we have reported identification and characterization of a novel BCL2 inhibitor, Disarib. Disarib induced cancer cell death in a BCL2 dependent manner in different cancer cell lines and mouse tumor models when it was administered intraperitoneally. In the present study, using two syngeneic mouse models, breast adenocarcinoma (EAC) and Dalton's lymphoma (DLA), we show that oral administration of Disarib resulted in significant tumor regression in a concentration dependent manner. Importantly, tumor developed in both female and male mice were equally sensitive to Disarib. Further, we have investigated the toxicity of Disarib in normal cells. Single dose toxicity analysis of Disarib in male and female mice after oral administration revealed no significant variations compared to control group for parameters such as body weight, food and water consumption and behavioural changes which were analysed for the entire period of study. Haematological and histopathological analyses also did not show any significant difference from the control groups. Thus, our results reveal safe use of Disarib as a small molecule inhibitor and provide the foundation for investigation of other preclinical studies.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Indóis/uso terapêutico , Linfoma/tratamento farmacológico , Glândulas Mamárias Humanas/efeitos dos fármacos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Tiadiazóis/uso terapêutico , Administração Oral , Animais , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Hematopoese/efeitos dos fármacos , Humanos , Indóis/farmacologia , Masculino , Glândulas Mamárias Humanas/patologia , Neoplasias Mamárias Experimentais/diagnóstico , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Tiadiazóis/farmacologia
18.
Mol Carcinog ; 58(2): 219-233, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30298948

RESUMO

Efficient DNA repair is indispensable for maintaining genomic integrity in humans. Cancer associated deletions and mutations are mainly due to misrepaired DNA double-strand breaks (DSBs). Classical nonhomologous end joining (c-NHEJ) and homologous recombination (HR) are two major DSB repair pathways in humans. An error prone, alternative NHEJ pathway that utilizes microhomology was also reported in cancer cells and to a lesser extent in normal cells. In the present study, we evaluated the efficiency of various DSB repair pathways in the most common lymphoma, the diffuse large B cell lymphoma (DLBCL). Here we show that DNA repair through c-NHEJ pathway is limited in SUDHL8, a cell line derived from a DLBCL patient. Unlike c-NHEJ, microhomology mediated end joining (MMEJ) was predominant at physiological temperature. Consistent with the observation, expression level of repair proteins such as LIGASE I, LIGASE III, PARP1, CtIP, and MRE11 was higher in DLBCL cells when compared to c-NHEJ proteins. Further, inhibition of LIGASE I or MRE11, led to reduction in the efficiency of MMEJ in DLBCL cells. Besides, HR-mediated DSB repair occurring through gene conversion was observed. Thus, our results reveal the predominance of MMEJ over c-NHEJ in repairing DSBs in DLBCL cells, while error-free repair through HR was also evident.


Assuntos
Reparo do DNA , Redes Reguladoras de Genes , Linfoma Difuso de Grandes Células B/metabolismo , Regulação para Cima , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Endodesoxirribonucleases , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma Difuso de Grandes Células B/genética , Proteína Homóloga a MRE11/genética , Proteína Homóloga a MRE11/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo
19.
Asian J Psychiatr ; 6(6): 552-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24309871

RESUMO

Substance dependents often seek help for deaddiction and are detected positive during routine viral markers testing. We screened such patients in our hospital ShriGuru RamDas Institute of Medical Sciences and Research (SGRDIMSR) which is situated in a rural area adjoining the city of Amritsar; being a tertiary care centre it caters to a large population. A total of 1382 patients were admitted to the psychiatry ward from 01 July 2009 to 31 December 2012 and screened for study, out of whom 4.63% (n=64) refused to consent for participation in the study. Out of 1318 screened participants, 85.96% (n=1133) had opioid dependence, followed by tobacco (61.68%), alcohol (23.97%), cannabis (0.04%), and other substances (0.01%) including benzodiazepine, inhalants, etc. Out of 118 seropositive injection drug users (IDUs), 66.10% (n=78) patients were Hepatitis C positive, 15.25% (n=18) were detected as HIV reactive and 5.08% (n=6) patients were found to be HBsAg positive. This is significant as HCV is mostly overlooked in government health policies and overshadowed by HIV. Our study also emphasises the need for HCV screening along with HIV in various health programmes. Our study is important as it may help in reviewing health policies as HIV infection among IDUs is highest (30.40%) in this part of the country as per data by UNAIDS (National AIDS Control Organisation, 2010) and there is no comprehensive policy for Hepatitis B and C like that of HIV.


Assuntos
Infecções por HIV/epidemiologia , HIV/isolamento & purificação , Hepacivirus/isolamento & purificação , Antígenos de Superfície da Hepatite B/isolamento & purificação , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Infecções por HIV/diagnóstico , Soroprevalência de HIV , Hepatite B/diagnóstico , Hepatite C/diagnóstico , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos
20.
Indian J Dermatol ; 56(6): 663-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22345766

RESUMO

BACKGROUND: Nevus of Ota is common condition in Indian patients. The condition is more common in females, with a male-female ratio of 1:4.8. AIM: To evaluate long-term efficacy safety and stability of Q-switched ND:YAG laser in treatment of Nevus of Ota. DESIGN: 6 month follow-up of patients of Nevus of Ota, treated with Q-switched ND:YAG laser MATERIALS AND METHODS: Twenty-five patients of Nevus of Ota were treated with Q-switched ND:YAG laser for a period of 1 year and 9 months; patient had fitzpatricks skin type 4 and 5; detailed history, clinical examination, ophthalmoscopy, and otoscopy was done in all cases; clinical photographs were taken before and after the completion of treatments. Six-month follow-up was done after the last session. Response to treatment was graded based on physician's global assessment. RESULT: More than 70% improvement was seen in 15 patients (60%). Eight patients (32%) had moderate and two patients (8%) showed mild improvement.

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