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1.
Antioxidants (Basel) ; 10(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34573088

RESUMO

In this study, cell death regulation and induction in AML cell line from a relapsed MLL-rearranged cell model (MOLM-13) was investigated with doxorubin (Dox) and betulinic acid (BetA), singly and in combination. CyQUANT Direct® and Annexin V/propidium iodide double staining were used to measure the cytotoxic and cell death induction effects of the compounds, respectively. Reactive oxygen species (ROS) generation was measured using 2',7'-dichlorofluorescin diacetate staining. Expressions of proteins and genes were examined by Western blot and reverse transcription polymerase chain reaction analysis, respectively. BetA (20 µM) and Dox (1 µM) indicated a synergistic growth inhibitory effect on MOLM-13 cells. The combined drug caused more cells to reside in irreversible late apoptotic stage compared to the single treatments (p < 0.05). Elevation in ROS may be the synergistic mechanism involved in MOLM-13 cell death since ROS can directly disrupt mitochondrial activity. In contrast, in leukaemic U-937 cells, the combination treatments attenuated Dox-induced cell death. Dox and the drug combination selectively reduced (p < 0.05) a recently reported anti-apoptotic Bcl-2 protein isoform p15-20-Bcl-2 in MOLM-13 by our group, without affecting the usually reported p26-Bcl-2-α. Further studies using known inhibitors of apoptosis are required to confirm the potential of Dox-BetA combination to modulate these pathways.

2.
Sci Rep ; 11(1): 6665, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758228

RESUMO

Severe injuries are frequently accompanied by hemorrhagic shock and harbor an increased risk for complications. Local or systemic inflammation after trauma/hemorrhage may lead to a leaky intestinal epithelial barrier and subsequent translocation of gut microbiota, potentially worsening outcomes. To evaluate the extent with which trauma affects the gut microbiota composition, we performed a post hoc analysis of a murine model of polytrauma and hemorrhage. Four hours after injury, organs and plasma samples were collected, and the diversity and composition of the cecal microbiome were evaluated using 16S rRNA gene sequencing. Although cecal microbial alpha diversity and microbial community composition were not found to be different between experimental groups, norepinephrine support in shock animals resulted in increased alpha diversity, as indicated by higher numbers of distinct microbial features. We observed that the concentrations of proinflammatory mediators in plasma and intestinal tissue were associated with measures of microbial alpha and beta diversity and the presence of specific microbial drivers of inflammation, suggesting that the composition of the gut microbiome at the time of trauma, or shortly after trauma exposure, may play an important role in determining physiological outcomes. In conclusion, we found associations between measures of gut microbial alpha and beta diversity and the severity of systemic and local gut inflammation. Furthermore, our data suggest that four hours following injury is too early for development of global changes in the alpha diversity or community composition of the intestinal microbiome. Future investigations with increased temporal-spatial resolution are needed in order to fully elucidate the effects of trauma and shock on the gut microbiome, biological signatures of inflammation, and proximal and distal outcomes.


Assuntos
Biomarcadores , Microbioma Gastrointestinal , Inflamação/etiologia , Inflamação/metabolismo , Traumatismo Múltiplo/complicações , Choque/complicações , Animais , Biodiversidade , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Inflamação/diagnóstico , Masculino , Metagenômica , Camundongos , Traumatismo Múltiplo/etiologia , RNA Ribossômico 16S , Curva ROC , Choque/etiologia , Aprendizado de Máquina Supervisionado
3.
Int J Oncol ; 57(1): 113-121, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32377726

RESUMO

The overexpression of anti­apoptotic Bcl­2 in acute myeloid leukaemia (AML) may contribute to difficulties in eradicating these cells during chemotherapy. In the present study, doxorubicin (Dox) was evaluated for its potential to induce selective apoptotic cell death in AML MOLM­13 cells and to modulate autophagy through Bcl­2 and Beclin 1 protein expression. Annexin V/propidium iodide and 5(6)­carboxyfluorescein diacetate succinimidyl ester (CFSE) flow cytometric analyses were conducted to determine the effects of Dox on cell death and cell proliferation, respectively, following 48 h of co­incubation with AML MOLM­13 or U­937 monocytic cells. The protein expression levels of Bcl­2 and Beclin 1 in untreated and treated cells were quantified by western blot analysis. Dox reduced the viability of MOLM­13 cells partly by inhibiting cell division and inducing cell apoptosis. Dox demonstrated a level of selectivity in its cytotoxicity against MOLM­13 compared to U­937 cells (P<0.05). Dox induced a significant decrease in Beclin 1 protein levels in MOLM­13 cells without significantly affecting the protein levels in U­937 monocytes. A novel Bcl­2 15­20 kDa (p15­20­Bcl­2) isoform was found to be selectively expressed in AML MOLM­13 cells (but absent in the leukaemic cell lines tested, OCI­AML2, CML K562 and U­937). Dox induced a highly significant inhibition of p15­20­Bcl­2 at concentrations of 0.5, 0.75 and 1 µM (P<0.01). However, the usual 26 kDa Bcl­2 (p26­Bcl­2­α) isoform protein expression was not affected by the drug in either the MOLM­13 or U­937 cells. It was thus postulated that Dox exhibited some selectivity by targeting the p15­20­Bcl­2 isoform in MOLM­13 cells and activating Beclin 1 to induce cell death.


Assuntos
Proteína Beclina-1/metabolismo , Doxorrubicina/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/patologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
Front Physiol ; 11: 524833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33469429

RESUMO

Previous studies demonstrate that Mycobacterium vaccae NCTC 11659 (M. vaccae), a soil-derived bacterium with anti-inflammatory and immunoregulatory properties, is a potentially useful countermeasure against negative outcomes to stressors. Here we used male C57BL/6NCrl mice to determine if repeated immunization with M. vaccae is an effective countermeasure in a "two hit" stress exposure model of chronic disruption of rhythms (CDR) followed by acute social defeat (SD). On day -28, mice received implants of biotelemetric recording devices to monitor 24-h rhythms of locomotor activity. Mice were subsequently treated with a heat-killed preparation of M. vaccae (0.1 mg, administered subcutaneously on days -21, -14, -7, and 27) or borate-buffered saline vehicle. Mice were then exposed to 8 consecutive weeks of either stable normal 12:12 h light:dark (LD) conditions or CDR, consisting of 12-h reversals of the LD cycle every 7 days (days 0-56). Finally, mice were exposed to either a 10-min SD or a home cage control condition on day 54. All mice were exposed to object location memory testing 24 h following SD. The gut microbiome and metabolome were assessed in fecal samples collected on days -1, 48, and 62 using 16S rRNA gene sequence and LC-MS/MS spectral data, respectively; the plasma metabolome was additionally measured on day 64. Among mice exposed to normal LD conditions, immunization with M. vaccae induced a shift toward a more proactive behavioral coping response to SD as measured by increases in scouting and avoiding an approaching male CD-1 aggressor, and decreases in submissive upright defensive postures. In the object location memory test, exposure to SD increased cognitive function in CDR mice previously immunized with M. vaccae. Immunization with M. vaccae stabilized the gut microbiome, attenuating CDR-induced reductions in alpha diversity and decreasing within-group measures of beta diversity. Immunization with M. vaccae also increased the relative abundance of 1-heptadecanoyl-sn-glycero-3-phosphocholine, a lysophospholipid, in plasma. Together, these data support the hypothesis that immunization with M. vaccae stabilizes the gut microbiome, induces a shift toward a more proactive response to stress exposure, and promotes stress resilience.

5.
Mol Med Rep ; 17(3): 4524-4530, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29328378

RESUMO

Baicalein (BL), a potential cancer chemopreventative flavone, has been reported to inhibit cancer cell growth by inducing apoptosis and causing cell cycle arrest in various human cancer cell models. Delivery of BL via nanoliposomes has been shown to improve its oral bioavailability and long­circulating property in vivo. However, the role of BL in the inhibition of human chronic myeloid leukemia (CML) K562 cell growth and its underlying mechanisms has yet to be elucidated. In the present study, BL was formulated into liposomes with different sizes to improve its solubility and stability. The cytotoxic and pro­apoptotic effects of free BL and liposomal BL were also evaluated. The results demonstrated that 100 nm liposomes were the most stable formulation when compared with 200 and 400 nm liposomes. Liposomal BL inhibited K562 cell growth as efficiently as free BL (prepared in DMSO), indicating that the liposome may be a potential vehicle to deliver BL for the treatment of CML. Flow cytometry analysis showed that there was significant (P<0.005) cell cycle arrest in the sub­G1 phase (compared with vehicle control), indicating cell apoptosis following 20 µM liposomal BL or free BL treatment of K562 cells for 48 h. The induction of cell apoptosis by all BL preparations was further confirmed through the staining of treated cells with Annexin V­fluorescein isothiocyanate/propidium iodide. A significant increase in reactive oxygen species (ROS) gene-ration was observed in free BL and liposomal BL treated cells, with a higher level of ROS produced from those treated with free BL. This indicated that cell apoptosis induced by BL may be via ROS generation and liposome delivery may further extend the effect through its long­circulating property.


Assuntos
Apoptose/efeitos dos fármacos , Flavanonas/farmacologia , Lipossomos/química , Espécies Reativas de Oxigênio/metabolismo , Proliferação de Células/efeitos dos fármacos , Flavanonas/química , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Células K562
6.
Eur J Hosp Pharm ; 25(e1): e21-e28, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31157062

RESUMO

OBJECTIVES: The role of clinical pharmacists in hospitals has evolved and continues to expand. In the UK, outside of a few national policy drivers, there are no agreed priorities, measures or defined outcomes for hospital clinical pharmacy (CP). This paper aims to (1) highlight the need to identify and prioritise specific CP roles, responsibilities and practices that will bring the greatest benefit to patients and health systems and (2) describe systematic weaknesses in current research methodologies for evaluating CP services and propose a different approach. METHOD: Published reviews of CP services are discussed using the Economic, Clinical and Humanistic Outcomes framework. Recurring themes regarding study methodologies, measurements and outcomes are used to highlight current weaknesses in studies evaluating CP. RESULTS: Published studies aiming to demonstrate the economic, clinical or humanistic outcomes of CP often suffer from poor research design and inconsistencies in interventions, measurements and outcomes. This has caused difficulties in drawing meaningful conclusions regarding CP's definitive contribution to patient outcomes. CONCLUSION: There is a need for more research work in National Health Service (NHS) hospitals, employing a different paradigm to address some of the weaknesses of existing research on CP practice. We propose a mixed-methods approach, including qualitative research designs, and with emphasis on cost-consequence analyses for economic evaluations. This approach will provide more meaningful data to inform policy and demonstrate the contribution of hospital CP activities to patient care and the NHS.

7.
Int Rev Neurobiol ; 135: 149-180, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28807157

RESUMO

Practitioners of traditional Chinese medicine (TCM) commonly prescribe medicinal formulations relying on the purported synergism of a combination of plant species, sometimes incorporating animal parts and minerals. Bear bile, obtained from either wild or farmed bears, is a commonly used constituent of traditional medicine formulations. With several bear species now listed under Convention on International Trade in Endangered Species of Wild Fauna and Flora as threatened with extinction and with bear farming being actively campaigned against on ethical grounds, it is important to seek and promote alternatives to the use of bear bile as medicine. This chapter describes and evaluates the scientific data relating to the efficacy of bear bile and potential alternatives to its use, including the use of bile from other animal species, the use of synthetic chemical alternatives, and the use of herbal substitutes. Scientific studies have confirmed the efficacy of bear bile as an antiinflammatory and a hepatoprotective agent. Ursodeoxycholic acid (UDCA), the active component of bear bile is used in a synthetic form in Western medicine and can serve as an alternative to bear bile in the treatment and management of certain cholestatic liver conditions. In TCM practice, bile from domesticated animal species (such as cattle, chicken, and pig) has been used as a substitute for bear bile. Following evaluation of TCM literature and pharmacological/clinical data, the authors propose six plant species, either as single herbs or in combination, Gardenia jasminoides (zhi zi; ), Scutellaria baicalensis (huáng qín; ), Coptis chinensis (huáng lián, ), Phellodendron amurense (huáng bai; ), Andrographis paniculata (chuan xin lian; ), and Rheum palmatum (dà huang; ), two medicinal Kampo formulations, Orengedokuto, Dia-Orengedokuto (which originated from traditional Chinese herbal formula Huanglian Jiedu Tang, ), and two individual phytochemicals (berberine and andrographolide) as alternatives to bear bile. The proposed herbal alternatives are frequently found listed in traditional formulations also containing bear bile, usually with different therapeutic roles ascribed to them. The existing evidence base for the effectiveness of herbal alternatives is sufficiently strong for TCM practitioners and consumers to consider using these without the addition of bear bile. This consideration is driven by the imperative to protect populations of bears from overexploitation in the wild and when farmed. However, for the identified alternatives to be accepted by users, it is essential that researchers and TCM practitioners collaborate effectively to initiate consumer behavior change.


Assuntos
Anti-Inflamatórios/uso terapêutico , Bile/química , Inflamação/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , Plantas Medicinais , Ursidae/metabolismo , Animais , Bile/metabolismo , Humanos , Plantas Medicinais/química
8.
Int Rev Neurobiol ; 135: 249-278, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28807161

RESUMO

Advances in scientific research and targeted treatment regimes have improved survival rates for many cancers over the past few decades. However, for some types of leukemia, including acute lymphoblastic and acute myeloid leukemia, mortality rates have continued to rise, with chemoresistance in leukemic stem cells (LSCs) being a major contributing factor. Most cancer drug therapies act by inducing apoptosis in dividing cells but are ineffective in targeting quiescent LSCs. Niches in the bone marrow, known as leukemic niches, behave as "sanctuaries" where LSCs acquire drug resistance. This review explores the role of the bone marrow environment in the maintenance of LSCs and its contribution to chemoresistance and considers current research on the potential use of phytochemicals to overcome chemoresistance through the modulation of signaling pathways involved in the survival and death of leukemic clonal cells and/or leukemic stem cells. Phytochemicals from traditional Chinese medicine, namely baicalein, chrysin, wogonin (constituents of Scutellaria baicalensis; huáng qín; ), curcumin (a constituent of Curcuma longa, jiang huáng, ), and resveratrol (a constituent of Polygonum cuspidatum; hu zhàng, ) have been shown to induce apoptosis in leukemic cell lines, with curcumin and resveratrol also causing cell death via the induction of autophagy (a nonapoptotic pathway). In order to be effective in eliminating LSCs, it is important to target signaling pathways (such as Wnt/ß-catenin, Notch, and Hedgehog). Resveratrol has been reported to induce apoptosis in leukemic cells through the inhibition of the Notch and Sonic hedgehog signaling pathways, therefore showing potential to affect LSCs. While these findings are of interest, there is a lack of reported research on the modulatory effect of phytochemicals on the autophagic cell death pathway in leukemia, and on the signaling pathways involved in the maintenance of LSCs, highlighting the need for further work in these areas.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Animais , Medula Óssea/anatomia & histologia , Humanos , Nicho de Células-Tronco
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